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Supplementation of the diet of adult male rats with 4,000 ppm zinc as ZnSO4 for 30 to 32 days increased the zinc content in the testis and sperm by 25 and 18 per cent respectively, but did not change the same in accessory reproductive tissues, e.g. epididymis, seminal vesicle and prostate. The incidence of conception from mating between normal females and zinc fed males was lower as compared to mating between normal females and control males. This observation indicated reduced fertility of the males resulting from additional zinc ingestion. Motility of the sperm collected from the epididymis (tail) of the zinc treated rats was found to be inhibited. It has been suggested that excess zinc in the sperm was responsible for their poor motility and hence a reduced fertilising capacity.  相似文献   
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The methanolic fraction of P. indica root extract was found to possess significant antiulcer activity in different experimental animal models. In preventive antiulcer tests, significant protective actions in acetylsalicylic acid, serotonin and indomethacin-induced gastric lesions were observed in experimental rats. The extract also afforded significant protection to chemically-induced duodenal lesion in guineapigs. Significant enhancement of healing process in acetic acid-induced chronic gastric lesions were also observed in the extract-treated animals.  相似文献   
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A case report of a male aged 31 who, after a journey to Bangladesh, returned with a disease resembling acute hepatitis A. Closer study revealed a hepatitis E infection. He recovered in slightly over two weeks.  相似文献   
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Mirror movements (MM) occur in early, asymmetric Parkinson's disease (PD). To examine the pathophysiology of MM in PD, we studied 13 PD patients with MM (PD-MM), 7 PD patients without MM (PD-NM), and 14 normal subjects. Cross-correlogram did not detect common synaptic input to motoneuron pools innervating homologous hand muscles in PD-MM patients. Transcranial magnetic stimulation studies showed no significant difference in ipsilateral motor-evoked potentials between PD-MM patients and normal subjects. The MM side of PD-MM patients showed a slower increase in ipsilateral silent period area with higher level of muscle contraction than the non-MM side and normal subjects. There was less interhemispheric inhibition (IHI) at long interstimulus intervals of 20 to 50 ms in PD-MM than PD-NM. IHI reduced short interval intracortical inhibition in normal subjects and PD-NM, but not in PD-MM. IHI significantly increased intracortical facilitation in PD-MM and PD-NM patients, but not in normal subjects. Our results suggest that MM in PD is due to activation of the contralateral motor cortex. PD-MM patients had reduced transcallosal inhibitory effects on cortical output neurons and on intracortical inhibitory circuits compared to PD-NM patients and controls. These deficits in transcallosal inhibition may contribute to MM in PD patients.  相似文献   
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The reduction of NBT to formazan has been suggested as an indicator of the reduction potential of biological systems. An increase in the amount of reduced formazan reflects the activation of the hexose monophosphate shunt of phagocytes cultivated in vitro, as a result of cellular stimulation by chemical or biological factors, or during phagocytosis. This phenomenon has been widely used for the determination of activated phagocytes by different methods. However, the technical limitations of these methods have not been evaluated carefully. In the investigations presented here threesolvents for formazan, pyridine, dioxane and dimethylformamide, have been tested for their suitability as extraction agents. For each solvent the optimal wavelength for photometric evaluation has been determined and dose relation curves between dissolved formazan and OD have been established. Several factors (time, temperature, pH, contamination with water or acid) affecting the dissolving properties and stability of formazan in different solvents have been investigated. With the solvents tested, dioxane proved to be the most suitable agent for extracting NBF. Thus, a methodology for the quantitative evaluation of NBT has been established. This method can be used for the identification of activators as well as of inhibitors of the phagocyte system.  相似文献   
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