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11.
An unexpected mortality of more than 300 cattle was investigated near a metal recovery factory located in a rural area of the Thane district of India. The factory was engaged in reclaiming lead, aluminium, tin, and zinc from discarded lead storage batteries and soft drink cans. The environmental samples (soil, leaves, grass, slag, water, and sediment), human blood and hair and animal samples (blood, urine, peritoneal fluid, liver, kidney, cow dung, ribs, and femur), collected for analysis revealed toxic levels of lead, cadmium, and chromium. Clinical examination of factory workers and school children revealed cough, fever, gastric problems, abdominal pain, skin lesions (scabies), and blue line on gums. Histopathological examination of animal tissues revealed chronic pathology with lead inclusion bodies in hepatocytes and renal tubules. Based on environmental, clinical, analytical, and histopathological observations, the mortality has been attributed to toxic levels of metals in the body and the malnourished status of the animals.  相似文献   
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Consecutive male (n=100) and female (n= 100) DSM-IV schizophrenics newly registered for treatment in a large psychiatric hospital were examined with regard to age at onset of the first psychotic symptom. Age at onset of the first psychotic symptom did not differ between the sexes regardless of whether schizophrenia was diagnosed by DSM-IV or by several alternative systems. Age at onset defined by other criteria, namely age at first contact with a physician, and age at first admission for psychiatric care, also did not show any differences between the sexes. Survival analysis of subjects having a documented date of birth revealed a female preponderance at younger ages. A higher positive symptom score predicted older age at onset of the first psychotic symptom in the total sample. These findings call into question the universality of the traditional view of a younger age at onset of schizophrenia among males. Tentative neurodevelopmental and cultural explanations are presented to explain why there is no sex difference in age at onset of schizophrenia in India.  相似文献   
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Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.  相似文献   
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Alpha and beta naphthols, the metabolites of naphthalene, a cataractogenic agent, was tested for it's effect on sheep lens proteases and their inhibitors. It reduced protease activities, not that of inhibitor activities of lens proteins. It also increased the efflux of free amino acid from lenses which was retarded by a high concentration of tissue galactose.  相似文献   
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We investigated the roles of two Rab-family proteins, Rab3a and Rab5a, in hippocampal synaptic transmission using real-time fluorescence imaging. During synaptic activity, Rab3a dissociated from synaptic vesicles and dispersed into neighbouring axonal regions. Dispersion required calcium-dependent exocytosis and was complete before the entire vesicle pool turned over. In contrast, even prolonged synaptic activity produced limited dispersion of Rab5a. A GTPase-deficient mutant, Rab3a (Q81L), dispersed more slowly than wild-type Rab3a, and decreased the rate of exocytosis and the size of the recycling pool of vesicles. While overexpression of Rab3a did not affect vesicle recycling, overexpression of Rab5a reduced the recycling pool size by 50%. We propose that while Rab3a preferentially associates with recycling synaptic vesicles and modulates their trafficking, Rab5a is largely excluded from recycling vesicles.  相似文献   
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In order to determine if mibolerone causes rapid development of the humoral immune system as previously hypothesized, 12-day-old chicken embryos were injected with 0.1, 1, or 10 micrograms mibolerone. Mibolerone caused bursal atrophy in a dose-dependent manner with severe atrophy at the 10 micrograms dose, substantial atrophy at the 1 microgram dose, and very little or no atrophy at the 0.1 microgram dose. Mibolerone-treated chicks were subsequently challenged with sheep red blood cells (SRBC) and Brucella abortus at 1, 7, 14, or 21 days of age. When serum samples were analysed for agglutinins to SRBC and B. abortus, the results indicated that treated chickens had lower agglutinin titers to both antigens at younger ages. These responses improved with age in groups treated with 0.1 microgram and 1 microgram and were comparable to controls at 5 weeks of age except for low primary and secondary (IgG specific) titers to B. abortus in birds treated with 1 microgram. Chickens treated with 10 micrograms mibolerone still had considerably lower primary responses to SRBC and lower primary as well as secondary responses to B. abortus at 4 and 5 weeks of age. These results indicate that mibolerone causes delayed rather than rapid development of the humoral immune system. In control as well as in treated chickens, agglutinin responses to SRBC appeared earlier than responses to B. abortus.  相似文献   
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