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AIMS--To evaluate a safe sputum processing method for detection of tuberculosis in developing countries. METHODS--A sample processing method was developed in which acid fast bacilli were killed with 1% sodium hypochlorite and concentrated by flotation on a layer of xylene before staining by the Ziehl Neelsen or auramine O methods. RESULTS--Best results were obtained by auramine O staining after flotation. Staining by the Ziehl Neelsen method after flotation gave better results than direct Ziehl Neelsen staining without flotation. CONCLUSIONS--The flotation method with Ziehl Neelsen staining offers advantages for smear preparation in the tuberculosis control programmes of developing countries.  相似文献   
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The peroxisome proliferator-activated receptor gamma (PPAR gamma) is a critical regulator of adipogenesis. PPAR gamma+/- mice are resistant to high-fat diet-induced obesity and thus PPAR gamma may mediate physiological responses to dietary fat in other mammals. The aim of this study was to determine whether the human PPAR gamma proline to alanine substitution polymorphism (Pro12Ala) modifies the association between dietary fat and adiposity and plasma lipids. Subjects (n=2141) were controls selected for three case-control studies nested within the Nurses' Health Study, a large ongoing prospective cohort study. Associations between intake of total fat, fat subtypes and BMI were different in PPAR gamma 12Ala variant allele-carriers compared with non-carriers. Among homozygous wild-type Pro/Pro individuals, those in the highest quintile of total fat intake, had significantly higher mean body mass index (BMI) compared with those in the lowest quintile (27.3 versus 25.4 kg/m2, respectively; P-trend<0.0001) whereas among 12Ala variant allele-carriers there was no significant trend observed between dietary fat intake and BMI (P-trend=0.99; P-interaction=0.003). In contrast, intake of monounsaturated fat was not associated with BMI among homozygous wild-type women but was inversely associated with BMI among 12Ala variant allele-carriers (mean in lowest quintile=27.6 versus mean in highest quintile=25.5 kg/m2; P-trend=0.006; P-interaction=0.003). The relationship between dietary fat intake and plasma lipid concentrations also differed according to PPAR gamma genotype. These data suggest that PPAR gamma genotype is an important factor in physiological responses to dietary fat in humans.  相似文献   
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Estrogen exposure influences breast and endometrial cancer risk. The HSD17B1 gene produces an enzyme that catalyzes the conversion of estrone to estradiol. We hypothesized that genetic variations in HSD17B1 gene may alter endogenous estrogen levels and, thus, influence endometrial and breast cancer risk. We validated and genotyped polymorphisms in the HSD17B1 gene and assessed whether these single nucleotide polymorphisms (SNPs), or the imputed haplotypes, were associated with endometrial and breast cancer risk. We also assessed whether a priori risk factors modified the associations between HSD17B1 genotype and cancer risk, and whether HSD17B1 genotypes were associated with plasma estrogen levels among postmenopausal women not using hormone replacement therapy. Ten SNPs of HSD17B1 gene were validated in 30 women from the Nurses' Health Study. Using the expectation maximization algorithm, three common (>5% frequency) haplotypes accounted for 97% of the chromosomes at this locus, and seven SNPs were in complete linkage disequilibrium. We identified and genotyped two haplotype-tagging SNPs (+1004C/T and +1322C/A), and genotyped an additional SNP [+1954A/G (Ser312Gly)] in nested case-control studies of endometrial cancer (cases = 222, controls = 666) and breast cancer (cases = 1007, controls = 1441) in the prospective Nurses' Health Study. Although no overall association by SNP or haplotype analysis was observed with endometrial or breast cancer risk, the +1954A/A genotype was associated with higher estradiol levels in lean women (P = 0.01) and interaction between the +1954 genotype with body mass index in postmenopausal breast cancer (P = 0.05) was suggested. These findings suggest that the HSD17B1 may be associated with circulating estradiol levels and interact with body mass index in postmenopausal breast cancer.  相似文献   
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Diltiazem has been extensively studied in the treatment of chronic anal fissures, but efficacy in clinical practice is not fully established. The aim of the present study was to evaluate the safety and efficacy of topical application diltiazem in observational studies as well as in controlled clinical trials in the treatment of chronic anal fissures. A systematic literature search was carried out from 1966 to 31 December, 2007 on PubMed, Medline, Embase and Cochrane database, using the appropriate search words. We found six observational studies with 392 patients and five controlled clinical trials with 289 patients in which topical diltiazem treatment was given. Efficacy was found to be very high in observational studies (56.88%), whereas it was found to be modest in controlled clinical trials (29.41%). In observational studies, most of the patients reported complete healing of fissures within 6–12 weeks, whereas in controlled trials healing was reported within 8 weeks, with tolerable adverse effects of diltiazem. On the basis of the above studies, it can be concluded that topical application of diltiazem is useful in the treatment of chronic anal fissure, but to fully establish its efficacy, larger prospective double-blind study is required in the near future.  相似文献   
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Adiposity may cause adverse health outcomes by increasing oxidative stress and systemic inflammation, which can be reflected by altered telomere length (TL) and mitochondrial DNA copy number (mtCN) in peripheral blood leukocytes. However, little is known about the influence of lifetime adiposity on TL and mtCN in later life. This study was performed to investigate the associations of lifetime adiposity with leukocyte TL and mtCN in 9613 participants from the Nurses’ Health Study. A group-based trajectory modelling approach was used to create trajectories of body shape from age 5 through 60 years, and a genetic risk score (GRS) was created based on 97 known adiposity susceptibility variants. Associations of body shape trajectories and GRS with dichotomized TL and mtCN were assessed by logistic regression models. After adjustment for lifestyle and dietary factors, compared with the lean-stable group, the lean-marked increase group had higher odds of having below-median TL (OR?=?1.18, 95% CI 1.04, 1.35; P?=?0.01), and the medium-marked increase group had higher odds of having below-median mtCN (OR?=?1.28, 95% CI 1.00, 1.64; P?=?0.047). There was a suggestive trend toward lower mtCN across the GRS quartiles (P for trend?=?0.07). In conclusion, telomere attrition may be accelerated by marked weight gain in middle life, whereas mtCN is likely to be reduced persistently by adiposity over the life course. The findings indicate the importance of lifetime weight management to preserve functional telomeres and mitochondria.  相似文献   
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Fungi are a relatively uncommon cause of brain abscess in neonates and early infancy. They are usually associated with predisposing factors like prematurity, low birth weight, use of broad-spectrum antibiotics, and prolonged stay in the intensive care unit. Candida tropicalis (C. tropicalis) is rapidly emerging as a nosocomial threat in the neonatal intensive care settings. This case report describes a neonate with C. tropicalis brain abscess who was diagnosed early and managed aggressively with a favorable outcome. Inadvertent use of intravenous antibiotics can have serious complications such as invasive fungal infection. Correct microbiological diagnosis is the key to successful treatment of deep-seated pyogenic infection. Fungal etiology should always be studied in relevant clinical settings.  相似文献   
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