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1.
Sister chromatid exchanges (SCE) were analyzed in peripheral blood lymphocytes from a select group of 71 healthy men, 56 nonsmokers and 15 cigarette smokers. In addition to estimating baseline SCE, data were examined to seek relationships of SCE frequencies to age and smoking. The baseline value of 7.53 SCE per cell from the 56 nonsmokers was within the range (5.60 to 9.10 SCE/cell) reported for other human populations. No relationship was found between the mean SCE frequency per cell and age. However, a significant increase in the SCE mean value was observed in smokers as compared to nonsmokers. The results of this study are compared with those of other reports on SCE effects of age and smoking.Abbreviations BUdR 5-bromo,2-deoxyuridine - SCE sister chromatid exchange  相似文献   
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Blood serum total cholesterol levels of crossbred Taur-indicus donor cows (n=22), in their 1st to 4th parity, were studied as an indicator of embryo yield. These cows were superovulated either with FSH or PMSG + anti-PMSG on the 12th day of the synchronized estrous cycle. The total and transferable number of embryos did not differ significantly between the treatment groups. The number of corpora lutea and total and transferable embryos in donors having total cholesterol levels <140 mg/dl were significantly (P < 0.05) lower than those of cows having >140 mg/dl, indicating that low total cholesterol levels might adversely affect superovulatory response. Thus, estimation of total cholesterol concentrations of potential donors can be a useful tool for predicting superovulatory responses.  相似文献   
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In this paper, we consider several variations of the following basic tiling problem: given a sequence of real numbers with two size-bound parameters, we want to find a set of tiles of maximum total weight such that each tiles satisfies the size bounds. A solution to this problem is important to a number of computational biology applications such as selecting genomic DNA fragments for PCR-based amplicon microarrays and performing homology searches with long sequence queries. Our goal is to design efficient algorithms with linear or near-linear time and space in the normal range of parameter values for these problems. For this purpose, we first discuss the solution to a basic online interval maximum problem via a sliding-window approach and show how to use this solution in a nontrivial manner for many of the tiling problems introduced. We also discuss NP-hardness results and approximation algorithms for generalizing our basic tiling problem to higher dimensions. Finally, computational results from applying our tiling algorithms to genomic sequences of five model eukaryotes are reported.  相似文献   
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Neurochemical changes in the extracellular fluid of the rostral ventrolateral medulla (RVLM) were produced by changes in arterial blood pressure. Blood pressure was raised or lowered with systemic infusions of phenylephrine or nitroprusside and neurochemicals were recovered from RVLM by in vivo microdialysis. A dialysis probe 300 microns in diameter and 500 microns in length was stereotaxically implanted in the RVLM of the urethane-anesthetized rat. Sterile physiological Ringer's solution was perfused at a rate of 1.5 microliter/min. The perfusate was collected under ice-cold conditions every 15 min for the assay of epinephrine, dihydroxyphenylacetic acid (DOPAC), 5-hydroxyindoleacetic acid (5-HIAA), ascorbic acid, and uric acid. After stable baseline neurochemical concentrations were achieved, animals were infused with phenylephrine or nitroprusside intravenously to raise or lower the blood pressure. Increasing blood pressure 50 mm Hg above the baseline value by phenylephrine led to a significant reduction in heart rate and a reduction in extracellular epinephrine and DOPAC concentrations. The 5-HIAA concentration was increased during the hypertensive drug infusion. There were no changes in the concentrations of ascorbic acid or uric acid. Hypotension produced by nitroprusside (-20 mm Hg) led to neurochemical changes which were the reciprocal of those seen during hypertension. During hypotension, heart rate increased as did the extracellular fluid epinephrine concentration. The 5-HIAA concentration fell with hypotension and remained depressed following the nitroprusside infusion. Ascorbic acid and uric acid concentrations did not change during hypotension but ascorbic acid did increase after the nitroprusside infusion stopped. These data provide direct evidence that epinephrine release in RVLM is linked to changes in systemic blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Liposomes are well known lipid carriers for drug delivery of bioactive molecules encapsulated inside their membrane. Liposomes as skin drug delivery systems were initially promoted primarily for localized effects with minimal systemic delivery. Subsequently, a novel vesicular system, transferosomes was reported for transdermal delivery with efficiency similar to subcutaneous injection. The multiple bilayered organizations of lipids applied in these vesicles structure are somewhat similar to complex nature of stratum corneal intercellular lipids domains. The incorporation of novel agents into these lipid vesicles results in the loss of entrapped markers but it is similar to fluidization of stratum corneum lipids on treatment with a penetration enhancer. This approach generated the utility of penetration enhancers/fluidizing agents in lipids vesicular systems for skin delivery. For the transdermal and topical applications of liposomes, fluidity of bilayer lipid membrane is rate limiting which governs the permeation. This article critically reviews the relevance of using different types of vesicles as a model for skin in permeation enhancement studies. This study has also been designed to encompass all enhancement measurements and analytical tools for characterization of permeability in liposomal vesicular system.  相似文献   
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This article seeks to document the vernacular perceptions of ‘globalization’ in rural Bengal (India) and, in that connection, seeks to rethink some long-held western notions concerning commodity, consumption, representation, the nature of sociality and the politics of democratic empowerment in the third-world. In the subaltern imaginary, images seem to play a crucial role conductive to empowerment. Also, far from resisting globalization and consumption, the rural poor seems to have assimilated these into their vernacular cosmology. In memoriam: Gourkishore Ghosh (1923–2001) Vernacular intellectual, publicist, crusader for free speech and democracy  相似文献   
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