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Metabolic Brain Disease - Leptin is an adipose tissue-derived hormone that acts on the hypothalamus in order to maintain energy homeostasis. However, leptin can also induce an inflammatory...  相似文献   
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Drugs that lack the ability to cross the blood-brain barrier (BBB) need to be placed directly into the central nervous system. Our laboratory studies the involvement of the glutamatergic system in the aggressiveness of glioma, and some ligands of glutamate receptors cannot permeate the BBB. Here, glioma-implanted rats were treated by a technique that delivers ligands directly into the cerebrospinal fluid by puncture into the cisterna cerebellomedullaris. Rats were anesthetized and fixed in a rodent stereotactic device. The head was gently tilted downwards at an angle that allowed exposure of the cisterna. Injection into the cisterna was done freehand using a gingival needle coupled to a microsyringe. The efficiency of intracisternal injection was demonstrated using a methylene blue solution. This type of injection is adaptable for any rodent model using small volumes of a variety of other drugs, and is an interesting method for neuroscience studies.  相似文献   
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Aim: The study analysed variability in physical stature, weight, and body mass index (BMI) in the USA during 1971–2002. Subjects: Subjects were non-Hispanic Blacks and Whites, 2–74 years of age from the National Health and Nutrition Examination Surveys (NHANES I–III and 1999–2002). Methods: The coefficient of variation and the standard deviation of the logarithm of stature, weight, and BMI were used to assess anthropometric variability for groups defined by age, race, sex, income, and survey year. Weighted ordinary least squares regressions were used to estimate the effect of socio-economic variables on anthropometric variability. Results: (a) The relation between age and variability in weight or BMI resembles an inverted U, (b) men have lower variability in BMI than women, (c) Blacks and the poor have greater variability in weight and BMI than Whites or than the non-poor, and (d) variability in anthropometric indices increased during 1971–2002. Results were robust to the measure of variability used and to the use of the mean and mean square of the anthropometric indicators as explanatory variables. Conclusion: Since anthropometric indices correlate reliably with canonical indicators of well-being (e.g. income), growing variability in anthropometric indices, particularly among the Blacks and the poor, signals growing inequality in quality of life—a worrisome trend.  相似文献   
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Background  

Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population.  相似文献   
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Background  There is good evidence for the use of compression for some clinical indications but little is known about dosimetry in compression.
Objective  The aim of this work was to evaluate whether or not the use of compression stockings during part of the day would help in the reduction of evening oedema in patients with clinical, epidemiological, anatomical and physiopathological (CEAP) classifications C0 and C1.
Methods  The effects of elastic compression stockings on volumetric variations during the working day were evaluated for the legs of two men and 18 women (40 legs). The inclusion criterion was classification as C0 (10 legs) or C1 (30 legs) according to the CEAP criteria. Participants used three-quarter-length elastic compression stockings (20–30 mmHg) on three consecutive days for the entire day or only for the morning or they did not use the stockings at all. Volumetry using the water displacement technique was performed in the morning and in the evening. When the patients wore the stockings only during the morning, volumetry was also performed at 13:00 h.
Results  Significant increases in volume were observed for both legs when stockings were not used compared with the use of stockings in the morning only. After removing the stockings, both legs had significant increases in volume in the afternoon. However, use for half the day was better than not using the stockings at all.
Conclusions  The use of elastic compression stockings can reduce volumetric variations during working hours, with the use of stockings for the entire day being better than for just half the day.  相似文献   
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The two components of the gastroesophagealbarrier, the sphincter and the crural sling, closelyoverlap in humans, whereas they are widely separated inthe rat. This investigation correlates the anatomical components of the barrier and their manometriccounterparts in this animal. Sphincteric and cruralsling pressures were measured in four quadrants in 23rats. Muscle thickness was measured at nine levels of the gastroesophageal junction in the samequadrants in 12 rats and the muscular architecture ofthe region was studied in 10 fresh specimens. Themanometric sphincteric component is stronger on theright side where the thickest muscle fibers anchor tothe anterior and posterior borders of a mucosal ridgethat almost surround the cardia. Conversely, the slingpressure is highest towards the left where the muscular bundles straddle the esophagus. Inconclusion, there is a close correspondence between themanometric image and the muscular architecture of thecomponents of the gastroesophageal barrier in the rat. The anatomical arrangement of U-shapedmuscular bundles oriented in opposite directions createsa particularly powerful antireflux mechanism.  相似文献   
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