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Micon L, Geis L, Siderys H, Stevens L, Rodman GH. Rupture of the distal thoracic esophagus following blunt trauma: case report. THE JOURNAL OF TRAUMA 1990; 30:214-7. [PMID: 2304118 DOI: 10.1097/00005373-199002000-00015] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Rupture of the distal thoracic esophagus is an unusual injury following blunt abdominal trauma. We recently encountered this injury in a patient following a relatively minor motor vehicle accident. An improperly positioned seatbelt was presumed contributory in this case. Prevention of further contamination and drainage of infection are primary objectives. Wide mediastinal drainage with repair, resection, or diversion are recommended, depending on the degree of mediastinitis present.
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Abstract
The volume of impressions, before and after disinfection in a gluteraldehyde solution for longer than ten hours (that is, sterilization), was measured indirectly from dies produced from the impressions. Three elastomeric impression materials were used in both acrylic resin and poly-vinyl-chloride 'trays' to form the impressions. One impression material appeared to be practically superior to the others with respect to variability of volume. The effect of tray material on change in volume (calculated as after disinfection minus before disinfection) was significant for one impression material; acrylic trays produced the greatest effect. The change in volume was significant for two impression materials; acrylic trays were associated with greater increase in volume. It was concluded that if impressions are to be sterilized, a tray material having minimal potential to absorb disinfectant should be used.
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203
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Stevens L, Wade MJ. Cytoplasmically inherited reproductive incompatibility in Tribolium flour beetles: the rate of spread and effect on population size. Genetics 1990; 124:367-72. [PMID: 2307358 PMCID: PMC1203928 DOI: 10.1093/genetics/124.2.367] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This paper reports on the effects of a cytoplasmically inherited reproductive incompatibility in different genetic strains of the flour beetle, Tribolium confusum. We measured the rate of spread and the effect of host population size using different initial frequencies of infection with a cytoplasmic factor that mediates reproductive incompatibility. There were two experiments, in one the infected and uninfected lines were from the same genetic strain, b-Yugoslavia. In the other, the infected line was from the "high cannibalism" bIV strain and the uninfected line from the "low cannibalism" bI strain. We estimate that the fitness ratio of infected to uninfected in b-Yugoslavia is 0.63 and the observed rate of spread for this strain corresponds to a model of cytoplasmic inheritance that takes into account the productivity differences between the infected and cured lines. In the bI-bIV experiment, because the uninfected and infected lines are from different genetic strains, we cannot partition the effects of the cytoplasmic factor from other factors. The rate of spread in the bI-bIV experiment is faster in males and slower in females than predicted from a model of cytoplasmic inheritance. In both experiments, productivity varies with initial infection frequency; however, the relationship is not explained by a simple model that predicts lower population size at intermediate infection frequencies.
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Holy X, Stevens L, Mounier Y. Compared effects of a 13 day spaceflight on the contractile proteins of soleus and plantaris rat muscles. THE PHYSIOLOGIST 1990; 33:S80-1. [PMID: 2371353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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205
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Stevens L, Mounier Y. Evidences for slow to fast changes in the contractile proteins of rat soleus muscle after hindlimb suspension: studies on skinned fibers. THE PHYSIOLOGIST 1990; 33:S90-1. [PMID: 2371358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Stevens L, Mounier Y, Holy X, Falempin M. Contractile properties of rat soleus muscle after 15 days of hindlimb suspension. J Appl Physiol (1985) 1990; 68:334-40. [PMID: 2312475 DOI: 10.1152/jappl.1990.68.1.334] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The properties of the contractile elements interacting to develop force in atrophied rat soleus muscle were studied by using single skinned fibers, which permitted direct access to the contractile apparatus. Muscle atrophy was induced by 15 days of hindlimb suspension. Suspension resulted in a decrease of maximal tension relative to an important decline in fiber diameter. Ca affinity of the contractile proteins was not changed insofar as the tension-pCa relationship was not shifted along the pCa axis. However, after hindlimb suspension 1) the value of the Hill coefficient from the tension-pCa curve was found to be higher, 2) a higher Ca threshold for activation was reported, and 3) a significant increase in contraction kinetics was described. All these results suggested that after suspension the mechanical properties of the slow-twitch soleus appeared to resemble more closely those of a fast-twitch muscle. Our results were in complete agreement with published histochemical data.
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Mounier Y, Holy X, Stevens L. Compared properties of the contractile system of skinned slow and fast rat muscle fibres. Pflugers Arch 1989; 415:136-41. [PMID: 2594471 DOI: 10.1007/bf00370583] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Chemically skinned fibres from soleus and plantaris rat muscles were used to compare the contractile properties of slow and fast muscles. The maximal isometric tension appeared larger in plantaris than in soleus fibres. The apparent Ca2+ threshold for activation was lower in slow than in fast fibres while Ca2+ concentrations required to obtain either the maximal tension or half maximal tension (pCa50) were lower in fast than in slow fibres. This apparent difference in Ca2+ sensitivity will be discussed. As could be expected from other studies, a faster force development in plantaris than in soleus fibres occurred. However, one interesting new result showed that in soleus, the kinetics of the tension development estimated by the tmax parameters were slightly dependent on the Ca2+ concentration whereas the t50 parameter changed significantly with the Ca2+ concentration. In plantaris, both tmax and t50 parameters were found to depend strongly on the Ca2+ concentration. Finally, the plantaris muscle showed a greater caffeine sensitivity than the soleus muscle. All the results suggested that the Ca-regulatory mechanism in the slow fibres was essentially different from that in the fast fibres.
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208
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Bruce WL, Stevens L. Strength properties of three zinc phosphate cements mixed to two different consistencies. Aust Dent J 1989; 34:132-5. [PMID: 2730428 DOI: 10.1111/j.1834-7819.1989.tb04622.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
When hand-mixing is used, clinicians mix zinc phosphate cement to consistencies which allow proper seating of restorations. Slump tests have indicated that the same two preferred consistencies (one for cementing a single unit restoration, the other for cementing a multiple unit restoration) could be obtained at different slab temperatures for three cements by mixing to certain powder-liquid ratios which were different for each cement. Each cement could be repeatedly mixed to the preferred consistency by using the appropriate powder-liquid ratio. The compressive and tensile strengths of the cements varied, although mixed to the same consistency. Selection of a cement for clinical use should be based on its strength properties when mixed to a preferred consistency.
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209
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Badylak SF, Stevens L, Janas W, Gray MH, Geddes LA, Voorhees WD. Cardiac assistance with electrically stimulated skeletal muscle. Med Biol Eng Comput 1989; 27:159-62. [PMID: 2532277 DOI: 10.1007/bf02446225] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This study examined the ability of a skeletal muscle-powered assist ventricle (SMV) to augment cardiac output in ten dogs with pharmacologically induced heart failure under acute conditions. An SMV was surgically constructed in each dog by wrapping the untrained rectus abdominis muscle around a compressible pouch that was inserted into a left ventricular apex-to-aortic vascular conduit. The multiple motor nerves to the rectus muscle were then stimulated during ventricular diastole at a rate which equalled a ratio of 1:2, 1:3, or 1:4 with the natural ventricular beat. There was an increased cardiac output during SMV assistance compared with preassistance values in all ten dogs at each stimulation ratio with a mean increase of 46 +/- 4 per cent with a ratio of 1:2, 25 +/- 4 per cent with a ratio of 1:3, and 31 +/- 7 per cent with a ratio of 1:4 (p less than 0.01 for all values). The diastolic blood pressure and mean blood pressure were both increased (p less than 0.01 and p less than 0.05, respectively) during SMV stimulation at ratios of 1:2 and 1:3, but not 1:4. We have shown that untrained rectus abdominis muscle, when used as the power supply for a SMV in an apico-aortic conduit, can temporarily augment cardiac output in dogs with pharmacologically induced heart failure.
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Stevens L, Duncan D, Robertson P. Purification and characterisation of NAD-glutamate dehydrogenase from Aspergillus nidulans. FEMS Microbiol Lett 1989; 48:173-7. [PMID: 2524418 DOI: 10.1111/j.1574-6968.1989.tb03294.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
NAD-Glutamate dehydrogenase has been purified from mycelia of A. nidulans. The enzyme comprises subunits of 110 kDa. It is located in the cytosol. It is completely denatured by 1.0 M guanidine hydrochloride, and is not renatured by subsequent dilution. Isophthalate is a strong competitive inhibitor and the enzyme is also inhibited by thiol reagents. The properties of the enzyme were compared to those from other fungi in terms of size, sensitivity to inhibitors, intracellular distribution and mode of regulation, and were found to resemble most closely those of Neurospora crassa.
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211
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Monfort SL, Dahl KD, Czekala NM, Stevens L, Bush M, Wildt DE. Monitoring ovarian function and pregnancy in the giant panda (Ailuropoda melanoleuca) by evaluating urinary bioactive FSH and steroid metabolites. JOURNAL OF REPRODUCTION AND FERTILITY 1989; 85:203-12. [PMID: 2492603 DOI: 10.1530/jrf.0.0850203] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Urinary excretion of oestrone conjugates, pregnanediol-3 alpha-glucuronide (PdG) and 20 alpha-hydroxypregn-4-en-3-one were measured from 8 weeks before oestrus to 2 weeks post partum and bioactive FSH was monitored during the periovulatory interval in a female giant panda. A biphasic urinary bioactive FSH excretory profile appeared to indicate a broad (approximately 10 day) follicular phase followed by a sharp preovulatory bioactive FSH surge coincident with an acute increase in urinary oestrone conjugates and behavioural oestrus. Weekly concentrations of urinary oestrone conjugates and PdG increased (P less than 0.001) by Week 9 of gestation with 20 alpha-hydroxypregn-4-en-3-one levels increasing 10-30-fold (P less than 0.001) between Weeks 11 and 14. These observations indicate that the monoestrous giant panda does not appear to require a prolonged period of endogenous FSH release or multiple FSH peaks for ovarian priming and follicle selection to proceed normally. Furthermore, the delayed rise in urinary steroid excretion during the second half of gestation in the giant panda supports the concept of delayed implantation while the estimation of steroid conjugates in urine offers a non-invasive approach for monitoring pregnancy status in this endangered species.
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Stevens L, Badylak SF, Janas W, Gray M, Geddes LA, Voorhees WD. A skeletal muscle ventricle made from rectus abdominis muscle in the dog. J Surg Res 1989; 46:84-9. [PMID: 2915538 DOI: 10.1016/0022-4804(89)90185-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This study examined the ability of a skeletal muscle-powered assist ventricle to augment cardiac output in 10 dogs with experimentally induced heart failure. Heart failure was induced with the use of the beta-blocking agents atenolol and propranolol. A "skeletal muscle ventricle" was then surgically constructed by wrapping the rectus abdominis muscle, with an intact neurovascular supply, around a double open-ended compressible pouch. The skeletal muscle ventricle was then interposed in a left ventricular apicoaortic conduit. The motor nerves to the skeletal muscle ventricle were stimulated by a custom designed pulse generator and caused tetanic contraction of the ventricle during diastole of every fourth natural heart beat. Stimulation was continued for 60 min. Cardiac output, systolic and diastolic blood pressures, mean blood pressure, left ventricular end diastolic pressure, and central venous pressure were then monitored prior to, during, and several times after skeletal muscle ventricle stimulation to evaluate assist ventricle function. There was an increased cardiac output in all 10 dogs at all recording times during skeletal muscle ventricle assistance compared to the cardiac output prior to stimulation of the assist ventricle. The mean increase in cardiac output after 30 min of assist ventricle stimulation was 31.0 +/- 14% (P less than 0.01), and at 60 min was 8.0 +/- 1% (P less than 0.05). The mean diastolic blood pressure after 1 and 30 min of skeletal muscle ventricle assistance (50.0 +/- 2.9 and 48.6 +/- 2.2 mm Hg, respectively) was increased (P less than 0.05) vs the preassistance value (44.9 +/- 2.8 mm Hg).(ABSTRACT TRUNCATED AT 250 WORDS)
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213
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Glenn SW, Parsons OA, Stevens L. Effects of alcohol abuse and familial alcoholism on physical health in men and women. Health Psychol 1989; 8:325-41. [PMID: 2767022 DOI: 10.1037/0278-6133.8.3.325] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Detoxified alcoholic men (n = 76) and women (n = 72) and nonalcoholic control men (n = 50) and women (n = 51) were given a structured interview that assessed five categories of physical health: medical history, alcohol-related disorders, trauma history, drug use history, and, for females, female-related disorders. Approximately half the subjects in each group were family history positive for alcoholism. Significant differences between alcoholics and controls were found for all five categories; family history effects were significant for four of the five categories, and sex differences were present in two categories. The results indicate that (a) alcoholics suffer pervasive physical health difficulties, (b) a family history of alcoholism is predictive of health problems in both alcoholics and controls, (c) the effects of alcohol abuse and family history of alcoholism on health appear to be independent and additive, and (d) women may be more "illness prone" than men and exhibit an increased vulnerability to the adverse effects of alcoholism.
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214
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Stevens L. Environmental factors affecting reproductive incompatibility in flour beetles, genus Tribolium. J Invertebr Pathol 1989; 53:78-84. [PMID: 2915149 DOI: 10.1016/0022-2011(89)90076-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This paper reports the effect of high temperatures on the reproductive compatibility of geographic strains of flour beetles, Tribolium confusum. Some geographic strains are reproductively incompatible with other strains owing to a maternally inherited microorganism: Males infected with the microorganism are reproductively incompatible with uninfected females. All other crosses are fertile. Previous reports indicated that infected strains can be cured of the microorganisms by culturing the beetles on medium containing tetracycline and that cured males become reproductively compatible. This study reports that raising larvae at high temperatures (37 degrees C) promotes curing. The proportion of individuals cured is a function of sex and the period of exposure to high temperature.
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Stevens L, Halbrook H, Berron K, Spears C, Hormuth D. Conversion from cyclosporine to azathioprine in heart transplant recipients. THE JOURNAL OF HEART TRANSPLANTATION 1988; 7:119-22. [PMID: 3284982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cyclosporine has proved to be of benefit for heart transplantation. Complications of therapy, however, occasionally require discontinuation of the cyclosporine and replacement with azathioprine. We report two cases in which changing from cyclosporine to azathioprine was followed by fatal rejection episodes.
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219
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Glenn SW, Parsons OA, Sinha R, Stevens L. The effects of repeated withdrawals from alcohol on the memory of male and female alcoholics. Alcohol Alcohol 1988; 23:337-42. [PMID: 3228455 DOI: 10.1093/oxfordjournals.alcalc.a044826] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The measure of number of withdrawals, as a separate drinking variable of relevance to cognitive functioning in alcoholics, is a relatively uninvestigated measure. An ethanol withdrawal hypothesis has been suggested that would predict poorer cognitive performance with increased number of withdrawals from alcohol. In this study, the effects of withdrawals (defined as a 24 hr period of abstinence following the consumption of alcohol) on tests of learning and memory were examined. Using 76 male and 67 female alcoholics, results indicate that greater number of withdrawals is related to poorer memory test performance. Results provide support for the ethanol hypothesis of poorer cognitive performance with increasing number of withdrawals, and suggest that females may exhibit accelerated responses to the effects of alcohol misuse.
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220
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Darveniza M, Basford KE, Meek J, Stevens L. The effects of surface roughness and surface area on the retention of crowns luted with zinc phosphate cement. Aust Dent J 1987; 32:446-57. [PMID: 3328605 DOI: 10.1111/j.1834-7819.1987.tb01297.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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221
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222
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Decker F, Stevens L, Vancini M, Wedeking L. Using patient outcomes to evaluate community health nursing. NLN PUBLICATIONS 1987:115-24. [PMID: 3684538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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223
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226
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Stevens L, Brown J. Can noncardiac muscle provide useful cardiac assistance? Preliminary studies of the properties of skeletal muscle. Am Surg 1986; 52:423-7. [PMID: 2942069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The treatment of end-stage cardiac disease is the focus of extensive investigation. Both cardiac transplantation and mechanically powered assist devices are currently in use. However, transplant recipients are at constant risk of infection and rejection, and patients with mechanical assists are tethered to external driving devices. These limitations have led to the investigation of methods of cardiac support that rely on autogenous tissue. The current study tests the ability of skeletal muscle to produce cardiac-type work. The cephalic half of one rectus abdominis muscle was mobilized (taking care to preserve the attachment to the superior epigastric vessels) in 12 canines. The muscle was formed into a cylindric pouch around a bladder device. This allowed the determination of the pressure and flow produced by the muscle. The muscle was stimulated to contract at a rate of 60 contractions per minute using twin stimuli of 80 ms duration. The muscle pouch yielded a maximal isovolumetric pressure of 282 mm Hg, which equalled 245 per cent of the dog's systolic blood pressure. In addition, the pouch produced a flow of 1.88 L per minute (73% of the dog's cardiac output) and a power output of 0.22 watts (39% of the dog's left ventricular power), while pumping against an afterload of approximately 2/3 the systemic resistance. Also, the muscle demonstrated an ejection fraction of 62.7 per cent. These data indicate that a hydraulic pouch formed from rectus abdominis muscle is capable of pumping function that may be able to assist the compromised ventricle. However, total replacement of cardiac function does not seem feasible.(ABSTRACT TRUNCATED AT 250 WORDS)
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227
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Stevens L. The effect of time between mixing and heating on the expansion of phosphate bonded investment. Aust Dent J 1986; 31:207-13. [PMID: 3465297 DOI: 10.1111/j.1834-7819.1986.tb01201.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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228
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Davis SS, Galloway M, Burnham WR, Stevens L. In vitro and clinical studies on intravenous feeding mixtures comprising fat emulsion, amino acid and electrolytes. Clin Nutr 1986; 5:21-7. [PMID: 16831744 DOI: 10.1016/0261-5614(86)90038-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/1985] [Accepted: 06/24/1985] [Indexed: 12/01/2022]
Abstract
This paper describes the effect of the amino acid mixture Freamine II on the physical stability of Intralipid fat emulsion. The amino acid-fat emulsion mixture was also administered to patients requiring intravenous nutrition and its clinical and biochemical effects were assessed. The amino acid-fat emulsion mixture was stable on storage for 48 hours as judged by flocculation and particle growth measurements made in the presence of 20 mmol/1 monovalent cations at 2 mmol/1 diavalent cations. Long-term storage of mixtures containing Freamine II is not recommended because of an interaction between the emulsifier and the amino acids. In a small open trial patients maintained their serum albumin concentrations. There was no evidence of impaired pulmonary function even in those subjects with impaired fat clearance.
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Stevens L, Okamoto A, Jörgensen KD. Dimensional change in mould space on setting of phosphate bonded investment. Aust Dent J 1985; 30:281-4. [PMID: 3866530 DOI: 10.1111/j.1834-7819.1985.tb02509.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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231
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Brown J, Stevens L, Lynch L, Caldwell R, Girod D, Hurwitz R, Mahony L, King H. Surgery for discrete subvalvular aortic stenosis: actuarial survival, hemodynamic results, and acquired aortic regurgitation. Ann Thorac Surg 1985; 40:151-5. [PMID: 3161465 DOI: 10.1016/s0003-4975(10)60009-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Discrete membranous subaortic stenosis (DMSS) accounts for 8 to 30% of congenital left ventricular outflow obstruction. The immediate effectiveness of surgical resection of this discrete obstructing membrane has been well documented, but little has appeared regarding late clinical and hemodynamic follow-up. Fifty-three patients with DMSS underwent operation at our institution from 1957 to 1983. Most (78%) were symptomatic, 79% had left ventricular hypertrophy (LVH) by electrocardiogram, and 92% had roentgenographic evidence of cardiomegaly preoperatively. Catheterization revealed a mean preoperative left ventricular-aortic gradient of 89 mm Hg. Twenty-eight patients had associated aortic insufficiency (AI) on the initial aortogram. Seven patients acquired AI in the interim between the first and second preoperative catheterization. Our patients have been followed for up to 12 years postoperatively. There have been 2 early and 3 late deaths. (Actuarial analysis revealed 5- and 10-year survival of 95% and 83%, respectively.) Seventy-one percent of the previously symptomatic patients noted relief of their preoperative complaints, and 45% of those with LVH had a regression in voltage. Cardiomegaly as determined by chest roentgenogram decreased in 45%. The left ventricular-aortic gradient fell to an average of 35 mm Hg a year postoperatively. Surgical treatment of congenital subvalvular aortic stenosis is effective in reducing the preoperative symptoms and the left ventricular-aortic gradient. It appears that DMSS causes AI.
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Halbrook H, Stevens L, Beckman D, Hormuth D, Fehrenbacher J, Herod G. Heart transplantation at a private institution: a two year experience. THE JOURNAL OF HEART TRANSPLANTATION 1985; 4:353-6. [PMID: 3916507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Since October 1982, 45 patients were referred and 15 underwent orthotopic heart transplantations. Eleven patients are presently alive. The donor heart ischemic time averaged 104 minutes for locally procured hearts and 183 minutes for hearts harvested in distant cities. Ninety-three percent of the patients survived the perioperative period. Survival rate at six months was 84%, at one and two years 72% and 52%, respectively. The one year survivors spent 80% of their time out of the hospital. The average cost for the transplant admission was $58,023. Four patients died 11 days, 57 days, 8 and 12 months after the operation. During the first three months there were 0.75 rejection episodes, 1.13 infections and 1.40 other complications per patient. We conclude that heart transplantation can be successfully carried out at a private institution, with excellent survival rates and at reasonable costs. In spite of progress, infection and rejection still account for most of the mortality and morbidity.
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Stevens L, Kirk CR. The role of the health record practitioner in public health nursing and home health care agencies. TOPICS IN HEALTH RECORD MANAGEMENT 1985; 5:61-4. [PMID: 10270496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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235
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Abstract
Reproductive isolation is induced by microorganisms in diverse geographic strains of the flour beetle Tribolium confusum (Coleoptera:Tenebrionidae). The incompatibility between populations is due to nongenetic cytoplasmically inherited factors. Males of infected strains produce no progeny when crossed with females of noninfected strains; however, they produce "normal" numbers of progeny when crossed with infected females. Males from noninfected strains show no reproductive isolation. Infected strains of T. confusum can be cured when tetracycline or other antibiotics are added to the flour medium. "Cured" strains become partially reproductively isolated from all noncured strains including the source strain
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236
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L'Estrange P, Stevens L. Adverse effects of reduction in lower facial height on lip and tongue. AUSTRALIAN PROSTHODONTIC SOCIETY BULLETIN 1984; 14:35-38. [PMID: 6598957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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237
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Gindhart TD, Stevens L, Copley MP. Transformation and tumor promoter sensitive phosphoproteins in JB-6 mouse epidermal cells: one is also sensitive to heat stress. Carcinogenesis 1984; 5:1115-21. [PMID: 6467502 DOI: 10.1093/carcin/5.9.1115] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
JB-6 mouse epidermal cells undergo irreversible transformation when exposed to tumor-promoting agents such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Phosphoprotein changes related to transformation were sought in four tumor cell lines related to JB-6 cells. Two dimensional polyacrylamide gel electrophoresis showed altered abundances of five phosphoproteins in the tumor cell lines compared with five untransformed clones. The mol. wt. in Kilodaltons and isoelectric points in pH units were: 120/6.0, 80/4.5, 55/6.5, 37/5.0 and 23-25/4.5. In all four transformants pp80 was markedly decreased and the pp23-25 doublet increased. In two of the four transformants pp120 and pp55 were increased and pp37 decreased. Treatment of untransformed clones with TPA affected only one of the phosphoproteins altered in the transformants. Treatment of untransformed clones with TPA produced a 2-fold increase in pp80 after 5 h. pp80 returned to baseline levels by 24 h and changed little in the continuous presence of TPA for up to 96 h. The increase in pp80 with short term TPA treatment occurred in all of the untransformed clones but none of four transformants. Late preneoplastic (P+) JB-6 cells only require treatment with a tumor promoter to transform. Early preneoplastic (P-) JB-6 cells require prior transfection of DNA from late preneoplastic JB-6 cells to transform in response to tumor promoter treatment. Quantitative analysis of pp80 in early preneoplastic, late preneoplastic, and tumor cell lines showed an inverse relationship between the level of pp80 and degree of preneoplastic progression in these cells. pp80 represents approximately 2% of total cellular phosphoprotein in JB-6 cells, shows microheterogeneity of both mol. wt. and isoelectric point, occurs in the particulate fraction of cells and is readily solubilized by 1% Triton. pp80 is increased by heat stress and shares other properties with the recently described mammalian heat stress protein, hsp 80. pp80's decrease in four out of four tumor cell lines, inverse correlation with stage of preneoplastic progression and responsiveness to TPA in preneoplastic but not in tumor cell line suggest that pp80 may be closely linked to biochemical mechanisms underlying transformation in this cell system.
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Michel SL, Stevens L, Amodeo P, Morgenstern L. Surgical procedures in nonagenarians. West J Med 1984; 141:61-3. [PMID: 6475042 PMCID: PMC1021656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
During the hospital course of 225 nonagenarian patients who underwent 285 major operations-80% on the general, vascular, orthopedic and urologic services-overall morbidity was 37% and mortality 7.5%. The 100 emergency operations were associated with a higher morbidity and mortality rate. Nonsurvivors were more likely to have associated cardiac or cerebral medical conditions, higher utilization of intraoperative invasive hemodynamic monitoring and greater use of surgical intensive care units. Compared with all surgical patients, the nonagenarians were admitted twice as often to the surgical intensive care unit, required twice the number of hospital days, underwent intraoperative hemodynamic monitoring twice as frequently and incurred 200% greater hospital charges. We conclude that with careful evaluation and management, a nonagenarian patient presenting with a surgical condition can safely undergo necessary operative procedures.
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239
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Yudofsky SC, Stevens L, Silver J, Barsa J, Williams D. Propranolol in the treatment of rage and violent behavior associated with Korsakoff's psychosis. Am J Psychiatry 1984; 141:114-5. [PMID: 6691426 DOI: 10.1176/ajp.141.1.114] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Propranolol controlled the rage and violent behavior of a man with alcohol withdrawal, Korsakoff's psychosis, and seizures. The authors present evidence linking Korsakoff's psychosis and alcohol withdrawal to pathophysiologic alterations in CNS adrenergic amines and receptors.
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241
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Letts M, Stevens L, Coleman J, Kettner R. Puppetry and doll play as an adjunct to pediatric orthopaedics. J Pediatr Orthop 1983; 3:605-9. [PMID: 6655058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The loss of a considerable segment of body tissue is often psychologically more traumatic than is the actual surgery to the unprepared child. In an attempt to improve the preparation of the child for ablative surgery, as well as to facilitate the pre- and postoperative management of the pediatric patient and family, we have developed a system of doll play and puppetry to educate and prepare children for this type of surgery. Guilt feelings are minimized, an outlet for hostility is provided, and the ever present fear of the unknown is confronted and dealt with in a manner acceptable to the child. The nonthreatening role of this technique also helps alleviate parental fears and concerns. Our experience with this technique has confirmed its usefulness in the preoperative psychological preparation of young children facing amputation or major musculoskeletal procedures.
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242
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243
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Ansari H, Stevens L. Purification and properties of two neutral proteinases from Aspergillus nidulans. JOURNAL OF GENERAL MICROBIOLOGY 1983; 129:1637-44. [PMID: 6355383 DOI: 10.1099/00221287-129-6-1637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Two proteinases have been purified from mycelial extracts of Aspergillus nidulans. Both enzymes have pH optima between 6.5 and 7.5 and are inhibited by phenylmethane sulphonyl fluoride and by di-isopropyl fluorophosphate. The molecular weights and isoelectric points of proteinase I and proteinase II are 30 900 and 30 000, and 4.6 and 4.3, respectively. Both enzymes have a similar range of substrate specificities. The principal differences in their properties are that proteinase I is sensitive to inhibition by 1 mM mercurials whereas proteinase II is not appreciably inhibited at this concentration, and that proteinase I is much more sensitive to denaturation by urea, guanidine hydrochloride and sodium dodecyl sulphate.
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244
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Stevens L, Dix N, Thompstone A. Effects of high water activity on growth and metabolism in Aspergillus sejunctus. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/s0007-1536(83)80050-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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245
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Stevens R, Stevens L, Price NC. The stabilities of various thiol compounds used in protein purifications. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0307-4412(83)90048-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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247
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Stevens L. An additional measure to ensure unidirectional solidification in dental casting. Aust Dent J 1983; 28:33-5. [PMID: 6344854 DOI: 10.1111/j.1834-7819.1983.tb01066.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Abstract
5 subjects participated in a within-subjects design to determine the effect of paced abdominal breathing on EMG levels. After training in thoracic and abdominal breathing, each subject's respiration performance and EMG levels were assessed in both breathing modes via a counterbalanced A-B-A-B reversal design. Reliable effects of respiration training were observed in both breathing modes. No effects were observed on EMG measures. The results were discussed in relation to literature on approaches to respiration training which may target specific arousal indices other than electromyogram activity. The utility of dovetailing complementary treatment techniques such as respiration training and relaxation training which are specific to particular arousal indices was discussed.
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Ansari H, Stevens L. Detection of a proteinase inhibitor in Aspergillus nidulans. JOURNAL OF GENERAL MICROBIOLOGY 1983; 129:111-6. [PMID: 6339674 DOI: 10.1099/00221287-129-1-111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The activity of proteinases in mycelial extracts of Aspergillus nidulans increased during storage. The rate of activation increased with temperature. Three separate proteinase activities, differing in their electrophoretic mobilities on polyacrylamide gels, were readily detected at pH 6.5. Inhibitory activity, effective against all three proteinase activities, was also detected in fractions prepared from fresh mycelial extracts. The inhibitory factor(s) were heat-stable and non-dialysable. The inhibitory activity was lost during storage of mycelial extracts. It is proposed that the inhibitory factor(s) are digested by the proteinases during storage.
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Stevens L, Kuhn AT. Diatomite as a source of cristobalite for dental investments a differential thermal analysis study. Aust Dent J 1982; 27:238-42. [PMID: 6295351 DOI: 10.1111/j.1834-7819.1982.tb04104.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cristobalite can be obtained from diatomite by heat-treatment at relatively low temperatures and short times without the use of flux. The differential thermal analysis method used to examine the alpha leads to beta inversion was not as satisfactory as it might have been, and to determine the amount and crystallinity of cristobalite formed any such method should be supported by other techniques, in particular, X-ray diffraction. To determine the suitability or otherwise of cristobalite produced from diatomite for use in dental investments, dialatometric studies are indicated since the property of thermal expansion is of fundamental importance to a dental investment.
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