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61.
Fenvalerate (Fen) is a synthetic pyrethroid, which is commonly used for destroying a variety of insect pests damaging several vegetable, fruit, and cotton crops. This insecticide is also used to mitigate household insects like flies, cockroaches, mosquitoes, and so forth. Human beings are exposed to formulated Fen preparations mostly by inhalation during spraying in fields for crop protection, for control of household insects, and also during handling and packaging at manufacturing plants. Limited online information is available regarding toxic effects of formulated Fen exposure on mammalian reproductive system. The present study has been undertaken to investigate male reproductive toxic effects of a formulated preparation of Fen (20% EC) particularly in relation to steroidogenic alterations in testes and sera of rats exposed by nose-only inhalation for (4 hours/day and five days a week) for three months. The results indicate significant reduction in the weight of testes, epididymal sperm counts, and sperm motility, along with decrease in marker testicular enzymes for testosterone biosynthesis viz. 17-beta-hydroxy steroid dehydrogenase (17-beta-HSD) and glucose-6-phosphate dehydrogenase (G6PDH), leading to net decrease in serum testosterone concentration in group of rats exposed to one-fifth LC50 of Fen (20% EC) by inhalation (4 hours/day, five days a week) subchronically for three months. These results for the first time indicate the role of testosterone in Fen (20% EC)-induced male reproductive toxicity of rats subchronically exposed by inhalation probably due to neuroendocrine-mediated phenomenon and hormone-disrupting property of the insecticide.  相似文献   
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The Mouse Models of Cancer Consortium of the NCI sponsored a meeting of neuropathologists and veterinary pathologists in New York City in November of 2000. A rapidly growing number of genetically engineered mice (GEM) predisposed to tumors of the nervous system have led to a concomitant need for neuropathological evaluation and validation of these models. A panel of 13 pathologists reviewed material representing most of the available published and unpublished GEM models of medulloblastoma, primitive neuroectodermal tumor, astrocytoma, oligodendroglioma, mixed glioma, and tumors of the peripheral nerve. The GEM tumors were found to have many similarities and some distinct differences with respect to human disease. After review of the biology and pathology for all models presented, participants were split into groups reflective of clinical expertise in human pathology, tumor biology, neuroimaging, or treatment/intervention. Recommendations were made detailing an extensive and complete neuropathological characterization of animals. Importance was placed on including information on strains, tumor clonality, and examination for genetic mutation or altered gene expression characteristics of the corresponding human malignancy. Specific proposals were made to incorporate GEM models in emerging neuroradiological modalities. Recommendations were also made for preclinical validation of these models in cancer therapeutics, and for incorporation of surrogate markers of tumor burden to facilitate preclinical evaluation of new therapies.  相似文献   
63.
Parathyroid carcinoma is a rare cause of primary hyperparathyroidism and these tumours are usually hyperfunctional as opposed to other malignant endocrine tumors. Surgery is the only effective treatment while nonsurgical modalities yield poor results. We report a patient, who presented with palpable mass in the neck and severe hypercalcemia. He underwent debulking surgery and received allendronate, calcitonin, dacarbazine followed by in- situ alcohol instillation with some success.  相似文献   
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A pilot study of 29 patients for research on clinical depression employed the framework of cultural epidemiology to examine illness-related experience, meaning, behaviour with a Bengali version of the explanatory Model Interview Catalogue (EMIC). This report examined patterns of distress and stigma with reference to the most troubling patient-specified symptom. All subjects were psychiatric outpatients in the Institute of Psychiatry, Calcutta, and met Diagnostic and Statistical Manual (DSM)-IV criteria for a major depressive episode. Only 5 patients (17.2%) identified sadness as the most troubling problem, and 48.3% specified pains and other somatic symptoms instead. An internally consistent stigma scale with Cronbach's alpha of .67, comprised 13 items, was used to assess stigma. In addition to the scale score for each subject, the contribution of each item was reported and compared. A suggestive, though not significantly lower value of the stigma score for patients reporting somatic symptoms as most troubling, compared with sadness, was consistent with findings from prior studies showing a positive relationship between the magnitude of depression and stigma. These findings are discussed with reference to their impact on recognition and help seeking among patients, and recognition and management of depression by general practitioner. Culturally distinctive presentations and social contexts of depression and other mental illnesses should be addressed in professional training and public health communications.  相似文献   
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The objective of this study was to examine whether hemispheric superiority is determined more by stimulus type (facial, lexical) or content (neutral, emotional). A split, visual-field experiment was designed using a computer-based program with bilateral presentation (left visual-field, right visual-field) for four sets of stimuli: face (neutral, emotional) x word (neutral, emotional), N = 40. The dependent measures were the frequency of correct response and response latency of correct responses. The visual-field effect was nonsignificant for correct responses; however, the interaction of stimulus type x content was found significant. The interaction of visual-field x stimulus type was significant with response time as the dependent measure. Facial stimuli were processed faster in the left visual-field (a right hemispheric function) and lexical stimuli were processed faster in the right visual-field (a left hemispheric function). No hemispheric effect was observed for stimulus content.  相似文献   
69.
Liver dysfunction in severe birth asphyxia   总被引:1,自引:0,他引:1  
A total of 46 full term, appropriate for gestational age neonates were included in this study. Out of this, 31 infants had suffered severe birth asphyxia, while 15 normal babies formed the control group. The liver function tests of the asphyxiated group was deranged in 64.52% babies. There was 60% mortality in asphyxiated babies with deranged liver function. The serum levels of transaminases (SGOT, SGPT) and alkaline phosphatase in non-survivors were significantly higher than those of survivors.  相似文献   
70.
Ovarian fibroma--clinical and histopathological characteristics   总被引:2,自引:0,他引:2  
Twenty-three cases of ovarian fibroma, comprising 3% of all benign tumors seen over a 20-year period, were analyzed. It was unilateral in all cases affecting more commonly the left ovary (70%). Whilst a majority of cases (77%) were encountered in the reproductive age group, the tumor was rare before the second decade. Only in 13% of cases was ascitis clinically detectable. This was not influenced by the size and weight (average of 9.3 x 10.8 x 11.1 cm and 959 g, respectively) of the tumors; a smooth-surfaced tumor was, however, associated with a greater amount of peritoneal fluid. Varying degrees of calcification in some tumors are detectable on ultrasonography and occasionally on abdominal radiography. The classical Meig's Syndrome was seldom encountered. The histopathological features, diagnostic problems and management are discussed.  相似文献   
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