Adjuvant chemo(immuno-)-therapy of primary breast cancer with adriamycin-cyclophosphamide (and levamisole)--six-year evaluation

In a phase II-type study 52 patients with no signs of metastases but with a high risk of recurrence were treated with 6 courses of adriamycin-cyclophosphamide as adjuvant systemic therapy following modified radical mastectomy of primary breast cancer. Half of the patients were randomized to receive additional immunotherapy with levamisole for 2 yr. The scheduled dose and time regimen could be achieved in over 90% of patients. A comparison of the actuarial disease-free and overall survival with data reported in the literature indicates a similar positive effect of adjuvant systemic therapy as described in adjuvant studies using polychemotherapy regimens. Immunotherapy with levamisole has no effect on disease-free and overall survival but added to general toxicity. Particular attention was paid to psychological consequences of adjuvant systemic therapy; consistent attention by one specifically trained physician during the whole therapy and follow-up period was effective in coping with the emotional problems. The difficulties in treating recurrences after adjuvant therapy became apparent. A high rate of loco-regional recurrences and of cerebral metastases was noted.

Increased fluidity of a model membrane caused by tetrahydro-beta-carbolines

Alterations in membrane fluidity caused by alcohols and tetrahydro-beta-carbolines (THBCs) have been studied. Dipalmitoylphosphatidylcholine vesicles were used as a membrane preparation, and changes in the fluidity were revealed by two fluorescent probes: 1-anilinonaphthalene-8-sulfonic acid (1,8-ANS) and N-phenylnaphthylamine (NPN). It was found that THBCs, which are condensation products of tryptamine and formaldehyde or acetaldehyde, were at least 2 orders of magnitude more potent in causing fluidity changes than the comparable alcohols (methanol and ethanol). Both 1,8-ANS (binding close to the polar end of the phospholipid molecules) and NPN (binding to the hydrophobic region of the membrane) were able to reveal changes in membrane fluidity, although there were differences between the behavior of the two probes. The condensation product of acetaldehyde--the primary metabolite of ethanol--and tryptamine were found to be 200-300 times more potent in causing fluidity changes than ethanol itself (as determined with both 1,8-ANS and NPN).

Adjuvant intermittent chemoimmunotherapy for primary breast cancer: a prospective study with immunologic follow-up

In an interdisciplinary prospective study 50 patients surgically treated for breast cancer were treated with six monthly courses of aggressive adjuvant chemotherapy (adriamycin and cyclophosphamide) and were randomized to receive either immunotherapy with levamisole or no additional therapy. Probability of disease-free survival for the whole group is 54.9% at 42 months. There was no noticeable difference in disease-free survival for either pre- and postmenopausal women or for patients treated with or without levamisole. The addition of levamisole had no effect on the depression of in vitro immunologic functions during chemotherapy.

Short-term and long-term effects of chemoimmunotherapy on granulopoiesis: adjuvant therapy of breast cancer

The effect of adjuvant chemoimmunotherapy on normal human granulopoiesis has been studied. The short-term pattern of hemopoietic depletion and regeneration confirms that human bone marrow shows reaction to cytotoxic agents similarly to that observed in animal experiments. A regenerative response to the drug-induced depletion of the committed stem cell compartment occurs very early, thus suggesting local CFUC population size control of negative feedback from the early granulocytic compartments. Levamisole in that particular regimen did not influence the reaction pattern of granulopoiesis following cytotoxic drug exposure. A model of quantitative evaluation leads to a description of compartment changes which is compatible with the concepts of hemopoietic reaction to cytotoxic drugs. Of particular importance to the planning of adjuvant therapy is the observation of a long-term defect of granulopoiesis after discontinuation of chemotherapy. Studies like those presented here should be performed on any regimen of adjuvant therapy to select the least toxic regimen when several cytotoxic combinations with similar activities are available.

Role of guanine nucleotides in the stimulation of thyroid adenylate cyclase by prostaglandin E1 and cholera toxin

Cholera toxin in the presence of GTP increased adenylate cyclase activity in a purified bovine thyroid plasma membrane preparation, whereas, in the presence of guanosine 5'-(beta, gamma-imido)-triphosphate (Gpp(NH)P), cholera toxin had no stimulatory effect. Similarly, prostaglandin E1 enhanced the adenylate cyclase activity induced by GTP but not by Gpp(NH)p. Gpp(NH)p-stimulated adenylate cyclase activity, assayed with hydrolysis-resistant adenosine 5'-(beta, gamma-imido)-[32P]triphosphate as substrate and no ATP-regenerating system was inhibited by GDP in a competitive fashion. Furthermore, prostaglandin E1, but not cholera toxin, influenced the GDP inhibition of Gpp(NH)p-stimulated activity by increasing the concentration of GDP resulting in 50% inhibition approx. 2-fold. Inosyl nucleotides mimicked the effects of guanyl nucleotides on thyroid adenylate cyclase in that ITP could substitute for GTP in enhancing cholera toxin- and prostaglandin #1-induced activities and that inosine 5'(beta, gamma-imido)-triphosphate [Ipp(NH)p] was also a potent stimulator per se. Conclusions. (1) Cholera Toxin and prostaglandin E1 enhance thyroid adenylate cyclase activation by GTP (or ITP), but have no stimulatory effect on the Gpp(NH)p (or Ipp(NH)p) response; (2) the stimulatory effect of prostaglandin E1 on adenylate cyclase may result from decreased affinity for GDP at the guanine nucleotide regulatory site; (3) the date regarding cholera toxin stimulation of thyroid adenylate cyclase are consistent with the hypothesis that cholera toxin exerts its effect by inhibiting an endogenous GTPase.

Structural and biotransformational membrane changes in the liver and intestine during chronic ethanol administration

The binding of a fluorescent probe 1-anilinonaphthalene-8-sulphonic acid (1,8-ANS) to liver microsomal membranes was markedly increased after chronic ethanol administration while the binding of a non-ionised probe phenylnaphthylamine (PNA) was not altered. The increase in 1,8-ANS binding is in accordance with the simultaneous increase of the ethoxycoumarin O-de-ethylase activity and cytochrome P-450 concentration. Also the intestinal ethyoxycoumarin O-de-ethylase activity and cytochrome P-450 concentration were increased. No changes in the aryl hydrocarbon hydroxylase or UDP-glucuronosyltransferase activities were found. The chronic ehtanol administration increased the phospholipid amount in the liver microsomes and altered the fatty acid composition of microsomal phospholipids by decreasing the amount of oleic acid and increasing linoleic acid proportion. The data suggest that chronic ethanol administration may effect the biotransformation enzyme activities by changing the structural properties of the membranes as well as increasing the cytochrome P-450 concentration.

A further parallel between selective adaptation and contrast

It is generally believed that selective adaptation effects in speech perception are due to a reduction in sensitivity of auditory feature detectors. Recent evidence suggest that these effects may derive instead from contrast. In a further test of the contrast hypothesis, we conducted two experiments each involving both adaptation and contrast sessions with matching stimulus sets. During the adaptation sessions of Experiment 1, subjects identified two series of velar stimuli varying in voice onset time, [ga]-[kha] and [gi]-[khi], before and after adaptation with of the following stimuli: [ga], [kha], [gi], and [khi]. In the contrast session, subjects identified either of two ambiguous test items (drawn from near the phonetic boundaries of the [ga]-[kha] and the [gi]-[khi] series) following a single presentation of [ga], [kha], [gi], or [khi]. For both the adaptation and contrast sessions, (a) the [--a] test items were more greatly affected (in a contrast direction) by the [--a] than by the [--i] adaptor/context stimuli, and (b) the [--i] test items were not differentially affected by the [--1] and [--i] adaptor/context stimuli. An analogous design was used in Experiment 2, except that the stimulus sets varied in pitch rather than vowel quality. For both the adaptation and contrast sessions, the test items were not differentially affected by the pitch of the adaptor/context stimulus. These parallel results provide further evidence that adaptation effects are actually a form of contrast.

Sequential triple-valve replacement in a Jehovah's Witness

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A further parallel between selective adaptation and contrast

It is generally believed that selective adaptation effects in speech perception are due to a reduction in sensitivity of auditory feature detectors. Recent evidence suggest that these effects may derive instead from contrast. In a further test of the contrast hypothesis, we conducted two experiments each involving both adaptation and contrast sessions with matching stimulus sets. During the adaptation sessions of Experiment 1, subjects identified two series of velar stimuli varying in voice onset time, [ga]-[kha] and [gi]-[khi], before and after adaptation with of the following stimuli: [ga], [kha], [gi], and [khi]. In the contrast session, subjects identified either of two ambiguous test items (drawn from near the phonetic boundaries of the [ga]-[kha] and the [gi]-[khi] series) following a single presentation of [ga], [kha], [gi], or [khi]. For both the adaptation and contrast sessions, (a) the [--a] test items were more greatly affected (in a contrast direction) by the [--a] than by the [--i] adaptor/context stimuli, and (b) the [--i] test items were not differentially affected by the [--1] and [--i] adaptor/context stimuli. An analogous design was used in Experiment 2, except that the stimulus sets varied in pitch rather than vowel quality. For both the adaptation and contrast sessions, the test items were not differentially affected by the pitch of the adaptor/context stimulus. These parallel results provide further evidence that adaptation effects are actually a form of contrast.

Differences in the response of hepatic and intestinal drug metabolizing enzymes in rats following carbon tetrachloride and/or phenobarbital treatment

The activities of the microsomal drug metabolizing enzymes in the liver and intestinal mucosa of rats were studied after the intraperitoneal administration of carbon tetrachloride and/or subcutaneous phenobarbital administration. The membrane phospholipid content was decreased after carbon tetrachloride treatment indicating destruction in the membrane structure. Aryl hydrocarbon hydroxylase activity was decreased in the liver and intestinal mucosa after treatment with CCl4 alone and in combination with phenobarbital. The CCl4 treatment increased the intestinal epoxide hydratase activity but decreased the activity in the liver. The hepatic UDPglucuronosyltransferase was slightly induced by phenobarbital and the activity was elevated by the CCl4 treatment. In the intestinal mucosa the enhanced UDPglucuronosyltransferase activity was observed only after phenobarbital pretreatment and the activity was decreased by CCl4. These results support the view that epoxide hydratase and UDPglucuronosyltransferase enzymes occupy different locations in the endosplasmic reticulum of intestinal mucosa than of liver.

Changes of granulopoiesis during and after adjuvant chemotherapy of breast cancer

Adjuvant chemotherapy allows a study of the effects of cytotoxic drugs on natural human haematopoiesis. We describe serial studies of granulopoiesis performed during and after intermittent adjuvant chemotherapy for breast cancer (adriamycin plus cyclophosphamide, given for six courses at monthly intervals). After drug administration, a sequential wave of depletion and regeneration through successive granulopoietic compartments was observed. With repeated chemotherapy, moderate neutropenia developed, and the blood CFU-C pool size became progressively reduced. After the sixth chemotherapeutic course, granulopoietic regeneration was delayed. Following discontinuation of chemotherapy, a long-lasting (greater than 200 d) reduction of the blood CFU-C pool size, together with neutropenia and reduction of marrow segmented neutrophils, was observed, suggesting a defect of granulopoiesis with persistent granulopoietic hypoplasia. In patients with expected long survival, residual bone marrow damage should be added to the list of potential late side effects of cytotoxic drug therapy.

Dietary cholesterol-induced enhancement of hepatic biotransformation rate in male rats

Male rats were fed a cholesterol-free diet for 5 weeks, followed by a 2% cholesterol diet for 4 weeks. Another group of rats was continuously fed a cholesterol-free diet. A third group was fed standard pelllets during the whole experiment. Hepatic microsomal protein and cholesterol contents and drug-metabolizing enzyme activities were measured. The cholesterol-rich diet increased microsomal protein content and this increase disappeared after trypsin digestion of microsomal membranes. Microsomal cholesterol content was enhanced three-fold by cholesterol feeding. Cytochrome P-450 concentration, NADPH cytochrome c reductase and aryl hydrocarbon hydroxylase activities showed only minor changes following cholesterol feeding. The p-nitroanisole O-demethylase and ethoxycoumarin deethylase activities were doubled by cholesterol in comparison to cholesterol-free diet. Trypsin digestion activated the UDP-glucuronosyltransferase enzyme eight- to ten-fold on a protein basis. Trypsin treatment increased the cholesterol activation of UDP-glucuronosyltransferase when compared to the activity in native microsomes. The data suggest that dietary cholesterol regulates the cholesterol content of microsomal membranes. The activities of drug-metabolizing enzymes are also altered, possibly due to the compositional changes of the membranes.

Regulation of hepatic drug metabolism by elaidic and linoleic acids in rats

Elaidic and linoleic acids were administered at doses of 40 and 200 mg/kg i.p. every second day for 4 weeks to rats fed a fat-free diet. The fatty acids had only a slight effect on the weight gain of the animals. The amount of microsomal protein was slightly decreased with the higher dose of linoleic acid. The higher dose level of both fatty acids decreased the microsomal phospholipid content. The relative amounts of microsomal phospholipid fatty acids were also altered due to fatty acid administration. The activity of microsomal NADPH cytochrome c reductase and microsomal cytochrome P-450 contents were decreased by the higher dose of linoleic acid. The hepatic aryl hydrocarbon hydroxylase and p-nitroanisole O-demethylase activities decreased in fatty acid-treated rats. The UDP-glucuronosyltransferase activity was also lowered after the fatty acid administration. The results suggest that fatty acid-induced changes in the activities of drug-metabolizing enzymes may be due to the microenvironmental changes of membrane-bound enzymes.

Inhibition of thyroidal cyclic AMP-dependent protein kinase by thyroid hormone

Bovine thyroid cyclic AMP-dependent protein kinase was purified by DEAE-Sephadex and Sephadex G-200 chromatography. This preparation showed a 240-fold increase in specific activity over the initial 20,000 x g supernatant with histone as substrate and 1 micronM cyclic AMP in the assay mixture. In the presence of 2.5 X 10(-5)M L-triiodothyronine (T3), protein kinase activity was significantly reduced; 50% inhibition was achieved at 1 X 10(-4) M. Tests of diverse thyroid hormone analogs showed that T3 and its derivatives were more potent inhibitors than T4 and its derivatives which, in turn, were more potent than thyronine or diiodothyronine. Mono- and diiodotyrosine, tyrosine, and iodide were without effect. Triiodothyronine did not inhibit kidney, spleen, or lung protein kinase activity. The magnitude of the inhibition was the same whether or not cyclic AMP (1 micronM) was present in the incubation mixture, suggesting an effect on the catalytic, rather than the regulatory subunit of the enzyme. The inhibition of protein kinase by thyroid hormone was not influenced by Mg++ concentration but was overcome in a competitive manner by increasing ATP concentration. Increasing the histone concentration did not modify the inhibition. Although these studies suggest a novel cellular control mechanism, the high thyroid hormone concentrations required and the lack of concordance between inhibitory effects and biologic activity of the analogs tested precludes assumption of physiologic relevance.

Dietary cholesterol caused modification in the structure and function of rat hepatic microsomes, studied by fluorescent probes

A 4% cholesterol diet fed to rats for four weeks was found to increase the phospholipid and cholesterol contents and the activities of drug metabolizing enzymes in rat liver microsomes. Microsomes from rats on a high cholesterol diet were able to enhance the fluorescence of membrane bound 1-anilinonaphthalene 8-sulphonate (1,8-ANS) and ethidium bromide more than microsomes from rats on a standard diet. In the case of 1,8-ANS, the enhanced fluorescence was found to be due to the increased affinity of the molecules for microsomes. In the case of ethidium bromide the fluorescence increased partly because of the larger amount of binding sites and partly because of the enhanced quantum yield of the molecules. P-nitrophenol was found to compete with 1,8-ANS for the same binding sites in microsomes. On the other hand, 1,8-ANS lowered the rate of drug metabolism when present in the incubation mixture. In vitro treatments of microsomes with trypsin, phospholipase A or digitonin altered the binding properties of 1,8-ANS and ethidium bromide to microsomes. It is concluede that the binding sites of 1,8-ANS in microsomes are important for the activity of drug-metabolizing enzymes. The mechanisms of dietary cholesterol in enhancing the drug metabolism and the role of microsomal phospholipids in regulating the activity of drug-metabolizing enzymes are discussed.

Modifications of drug metabolism by disulfiram and diethyldithiocarbamate. II. D-Glucuronic acid pathway

Hepatic enzymes connected with the formation and metabolism of free D-glucuronic acid were affected in rats after treatment with disulfiram or diethyldithiocarbamate (300 mg/kg, intragastrically, per day, 4 X). The activities of UDPglucose dehydrogenase, UDPglucuronic acid pyrophosphatase, UDPglucuronosyltransferase and L-gulonate dehydrogenase were enhanced, while those of glucose-6-phosphate dehydrogenase, beta-glucuronidase and D-glucuronolactone dehydrogenase were inhibited. These changes were more pronounced with disulfiram than diethyldithiocarbamate. Treatment with phenobarbital (80 mg/kg, i.p., per day, 4 X) enhanced UDP glucuronosyl-transferase, but brought about different effects on the other enzymes. Concurrent administration of phenobarbital with disulfiram or diethyldithiocarbamate led to potentiation or antagonism of the primary effects of each compound when given alone. The results suggest that activation of the D-glucuronic acid pathway may proceed in various ways, and that it is not necessarily followed by a simultaneous induction of the microsomal mixed-function oxygenase activity.

Modifications of drug metabolism by disulfiram and diethyldithiocarbamate. I. Mixed-function oxygenase

Disulfiram and diethyldithiocarbamate were administered to rats for 4 days alone (300 mg/kg, daily, per os) or in combination with phenobarbital (80 mg/kg, daily, i.p.), in order to observe the effects of these compounds on the microsomal membrane components and on the mixed-function oxygenase system. Both disulfiram and diethyldithiocarbamate increased the liver to body weight ratio, and the total hepatic protein content. Disulfiram significantly increased also the microsomal protein and phospholipid contents. Diethyldithiocarbamate and disulfiram partially prevented the increase of microsomal protein and phospholipid contents caused by phenobarbital. Disulfiram and diethyldithiocarbamate decreased the amount of cytochrome P-450 and P-420, and the activity of p-nitroanisole O-demethylase. These changes were more pronounced after diethyldithiocarbamate than after disulfiram treatment. On the contrary, the activity of NADPH-cytochrome c reductase was enhanced only by disulfiram. The induction by phenobarbital of cytochrome P-450 and p-nitrosanisole O-demethylase was partially prevented on concomitant treatment with disulfiram and diethyldithiocarbamate. These compounds. however, had an additive effect with phenobarbital in enhancing the microsomal NADPH-cytochrome c reductase activity.

Antenatal sex determination in Macaca arctoides

Transabdominal amniocentesis was performed on 11 Macaca arctoides, between the 10th and 20th weeks of gestation, for the purpose of antenatal sex determination. The technique employing Y-chromatin fluorescence was unsuccessful in predicting sex, but the sexes were differentiated with complete accuracy by examining amniotic cells stained by a modified Papanicolaou technique. Of the cells from male fetuses, fewer than 10% contained X-chromatin (Barr bodies); of those from females, more than 45% contained X-chromatin.

Enhancement of hepatic drug biotransformation rate by polychlorinated biphenyls in rats fed cholesterol-rich diet

A combined effect of cholesterol and polychlorinated biphenyls (PCBs) on the microsomal drug hydroxylation and glucuronidation in the liver of the rat was studied. PCBs, Clophen A-50 and A-60, having an average chlorination degree of 50 and 60% affect the structure of microsomal membranes. It was found that Clophen A-60 increased the binding of trypsin- and digitonin-sensitive proteins to the membranes. Also it was found that PCBs enhanced the phsopholipid content of microsomes. PCBs increased the activity of hepatic NADPH cytochrome c reductase about 1.5-fold. Aryl hydrocarbon hydroxylase activity doubled with Clophen A-50 and quadrupled with Clophen A-60. Hepatic UDPglucuronosyltransferase activity was doubled with both PCBs. The enhancement in hepatic aryl hydrocarbon hydroxylase and in UDPglucuronosyltransferase was found to be lower in the presence of high cholesterol level in the diet when compared to earlier results. This is supposed to be due to the membraneous effects of cholesterol.

Further characterization of bovine thyroid prostaglandin synthase

1. Prostaglandin synthase activity (EC 1.14.99.1) was demonstrated in bovine thyroid homogenates. 2. The synthase was characterized and shares many characteristics of the well-studied seminal vesicle enzyme and can be inhibited by indomethacin and eicosa-5,8,11,14-tetraynoic acid. 3. The enzyme is localized in the microsomal fraction and is probably associated with the plasma membranes. 4. Thyrotropin, but no other hormone tested, increased the activity of the enzyme when added to a microsomal fraction obtained from bovine thyroid. This effect is tissue-specific since thyrotropin has no effect on bovine seminal esicle or lung prostaglandin synthase. 5. Thyrotropin, cyclic AMP and the phosphodiesterase inhibitors, theophylline and quazodine increase enzyme activity when preincubated with bovine thyroid slices. 6. EDTA, when included in the pre-incubation mixture, enhances the thyrotropin effect on the enzyme but not the cyclic AMP, theophylline, or quazodine augmentation of enzyme activity in bovine thyroid slices. This suggests that phospholipase A is involved in the thyrotropin stimulation of prostaglandin formation.

Inducibility of mucosal drug-metabolizing enzymes of rats fed on a cholesterol-rich diet by polychlorinated biphenyl, 3-methylcholanthrene and phenobarbitone

The results show that a cholesterol-rich diet changes the composition of mucosal membranes. A high cholesterol diet increases mucosal cholesterol and phospholipid contents. Cholesterol enhanced mucosal NADPH cytochrome c reductase and aryl hydrocarbon hydroxylase activities as well as mucosal UDP glucuronosyltransferase activity. When phenobarbitone or Clophen A 50 or 60 were administered intraperitoneally to cholesterol-fed rats, the hydroxylation and glucuronidation activities decreased to a lower level. 3-Methylcholanthrene was, however, able to maintain or increase mucosal hydroxylative enzymes and UDP glucuronosyltransferase. These results indicate that the drug-metabolizing enzymes of the intestinal mucosa behave very differently from those in the liver. Diet apparently has a regulatory effect on the induction of drug-metabolizing enzymes because only a very potent inducer, 3-methylcholanthrene, was able to maintain and even induce mucosal drug-metabolizing enzymes in rats fed on a high cholesterol diet, possibly through changes in the microenvironment of enzymes caused by cholesterol.

Geometrical aspects of consistent holographic memory design

Based on results of diffraction theory, it is shown that the proportions of storage plate and detector matrix, respectively, page-composer, of a fast holographic mass memory are strongly coupled. A high capacity fast data store needs a large detector array. Optimized geometry results if storage plate and detector matrix have the same size. A square detector matrix, able to read about 10(10) bits in an optimum designed memory, should have a diagonal extension of about 1 m.

The uptake by Escherichia coli and growth inhibitory properties of benzyl alcohol and phenethyl alcohol

The effects of benzyl alcohol (0–4 mg/ml) and phenethyl alcohol (0–2.5 mg/ml) on the rate of mass increase in cultures of E. coli were studied by absorbance measurements. Growth rate constants in the partially inhibited cultures were calculated. With both agents the growth rate was reduced on increasing the alcohol concentration, the extent of this reduction becoming progressively larger for equal increments in concentration. The inhibition of growth was shown to be reversible and to result from a uniform inhibition of the individual cells. The overall cellular uptake of benzyl alcohol was approximately the same as that of phenethyl alcohol. With both agents the uptake was proportional to the concentration of alcohol remaining in the medium and was independent of contact time within the range of 10–90 min. Phenethyl alcohol is, however, more effective than benzyl alcohol in inhibiting growth. This is attributed to a greater uptake of the former by the cellular membrane.

[Diagnostic and prognostic value of the EEG in the immediate aftermath of cranial trauma]

The authors studied the EGGs of 262 cases of post-traumatic coma and drew the following conclusions: 1. If the EEG shows sleep activity immediately after cranial trauma, the prognosis is generally good. 2. The existence of electrical reactivity to sensory stimulation is a favourable sign and examination of the symmetry of reactions often demonstrates a focal lesion which is not otherwise apparent. However, the absence of localizing signs in the EEG does not necessarily preclude the existence of an intracranial focal lesion; nor do signs of focalization necessarily confirm the existence of a lesion. 3. In equivocal cases, the echo-EG and arteriography should be contemplated. 4. Focal irritative abnormalities in an elderly patient suggest a very poor prognosis. 5. A recording which implies mtabolic disorder should prompt the immediate search for the causal disturbance. If correction of the metabolic disturbance is not followed by rapid improvement of the EEG, the prognosis is very unfavourable. 6. A focal lesion associated with the coma will affect the prognosis but surgical correction of the lesional effects may also get rid of the disturbances of consciousness.

A contribution to the comparison of single exposure and multiple exposure storage holograms

It is shown that it should be possible to produce single exposure holograms as well as multiple exposure holograms with the same diffraction efficiency if appropriate exposure conditions are used. The amplitude ratios between object wave and reference wave which must be employed in forming the hologram are specified for the two storage techniques. The object waves are provided to originate from a periodic array of coherent radiating light sources.