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71.
Mycobacterium tuberculosis complex (MTBC) causes tuberculosis (TB) in humans and animals. We investigated the presence of MTBC in cattle milk and its drug resistance using polymerase chain reaction (PCR). Two hundred samples (100 mL each) were obtained from a dairy farm in the Nkonkobe region of South Africa. The samples were processed using the modified Petroff method. DNA was isolated using a Zymo Bacterial DNA kit and amplified using Seeplex(?) MTB Nested ACE assay. The Genotype(?) Mycobacterium tuberculosis-multidrug resistantplus (MTBDRplus) assay was used to perform drug susceptibility and detection of mutations conferring resistance to isoniazid (INH) and rifampicin (RIF). Eleven samples tested positive for MTBC DNA using the Seeplex(?) MTB Nested ACE assay. The Genotype(?) MTBDRplus assay showed that 10/11 samples were resistant to both INH and RIF i.e., multi-drug resistant (MDR). The most and least frequent rpoB mutations detected in RIF resistant samples were H526Y (9/10) and D516V (2/10) respectively. None of the INH resistant samples harbored mutations in the katG gene. However, all of them harbored the T8A mutation in the inhA gene. These results have clinical and epidemiological significance and calls for further studies and necessary actions to delineate the situation.  相似文献   
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A longitudinal study of 151 children under five years of age was performed in a rural village of Burkina-Faso (West Africa). During systematic examinations by a physician during the rainy season, 44% of the children were found to be ill and 59% of these had an acute respiratory infection (ARI). During the dry season, the rates were 48% and 73% respectively. Weekly interviews by a field worker showed 6.2 attacks of ARI during the six months of the rainy season and 7.0 during the six months of the dry season. Risk factors for ARI were malnutrition assessed by arm circumference, and a high birth rank. At the 'field-dispensary', ARI accounted for 41% of the visits; lower respiratory infections (LRI) accounted for 24%, similar to the proportion of LRI among illnesses found during the systematic examination.  相似文献   
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Chylomicron remnants, but not lymph chylomicrons, showed a receptor-dependent high affinity saturable binding to normal rat hepatocytes. The Scatchard analysis of the specific binding data showed a high affinity binding site for the remnants with a dissociation constant of 0.61 nM, assuming a molecular weight of 50 X 10(6) for chylomicron remnants. Based on the heparin-releasable bound radioactivity, approximately 80% of the bound remnants seemed to be internalized. The binding process was markedly inhibited by pronase as well as by protein synthesis inhibitors. Competitive binding studies revealed that the order of competition for the binding of labeled remnants by homologous unlabeled lipoproteins was remnants greater than chylomicrons greater than very low density lipoproteins greater than high density lipoproteins. Human low density lipoproteins showed virtually no competition. Studies on the catabolism of triacylglycerol moiety of the remnants showed that 15.2% of the 14C label in the triacylglycerol moiety of the remnants was catabolized by the hepatocytes to 14CO2 due to specific interaction. This amounted to 93% of the total 14CO2 evolution. This was in sharp contrast to the catabolism of the triacylglycerol moiety of very low density lipoproteins from human and rat, where most of the 14CO2 evolution was due to pathways associated with nonspecific binding. Chronic ethanol feeding caused a 29% (p less than 0.02) decrease in the dissociation constant of the high affinity binding site of the liver cell for the remnants, whereas the extent of internalization was decreased by 19% (p less than 0.01) as compared to the pair-fed control animals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Identifying impaired drivers among the general driving population   总被引:2,自引:0,他引:2  
The primary purpose of this study was to identify predictors of impaired driving among a random sample of Canadian drivers who consume beverage alcohol. A second purpose was to determine if impaired drivers in the general population have characteristics similar to those reported among convicted and accident-involved impaired drivers. Amount of alcohol consumed over the past seven days was found to be the single most powerful predictor of both frequency of drinking-driving and of impaired driving. Impaired drivers differed from moderate-drinking drivers on a number of measures and were characterized by more irresponsible attitudes and higher risk behavior, consistent with findings of other impaired-driver subgroups. It is concluded that impaired driving may be just one behavior which is part of a deviant behavioral syndrome typified by high-risk behaviors.  相似文献   
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