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A selected suite of cytochemical parameters in Mytilus edulis are altered in response to field and laboratory exposure to chemical contaminants. These biomarkers include lysosomal stability, nicotinamide adenine dinucleotide phosphate (NADPH)–ferrihemoprotein reductase activity, liposfuscin deposition, and accumulation of lysosomal and cytoplasmic unsaturated neutral lipid. Normal variations in physiological processes (influenced by exogenous seasonal changes in temperature, salinity, food availability, etc.) may alter the sensitivity of these biomarkers to contaminant exposure. To address this issue, M. edulis (complex) were sampled monthly from a reference nonurban site (Coupeville, Penn Cove) and a polluted urban site (Seacrest, Elliott Bay) in Puget Sound, WA, for a period of 15 months. Physiological measurements including total length, total weight, somatic and mantle weights (an indication of gonadal development and reproductive status), condition index, and the presence or absence of hemic neoplasia (HN, or leukemia) were recorded. Significant differences in lysosomal stability, lysosomal and cytoplasmic unsaturated neutral lipids, lipofuscin deposition, and NADPH–ferrihemoprotein reductase activity in cells of the digestive gland or digestive tubules were generally found in mussels taken throughout the year from Seacrest compared to mussels sampled from Coupeville, consistent with exposure to chemical contaminants. No seasonally influenced suppression of the entire suite of parameters as measures of contaminant exposure was evident. Therefore these biomarkers can be used to evaluate contaminant exposure in mussels throughout the entire year. Received: 16 December 2001/Accepted: 30 May 2002  相似文献   
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Chronic cyanide intoxication from cassava has been implicated as the cause for a degenerative neuropathy known widely as tropical ataxic neuropathy. An attempt has been made in this study to identify the specific cause for neuropathy caused by cassava using Wistar strain albino rats as the experimental animal model. The results of cassava fed animals were compared with control animals, animals given cyanide, malnourished animals and malnourished animals fed cyanide, to identify the causative factors. This study revealed that though the behavioural pattern in motor coordination of the cassava fed animals was similar to the other groups studied, the neurochemical basis for the observed behavioural pattern was unique for cassava. Hence the neurotoxicity of cassava could be attributed to unmetabolized linamarin, more than its nutritional status and/or cyanide toxicity.  相似文献   
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Archives of Women's Mental Health - ‘Indigenous peoples’ across the globe suffer a disproportionate burden of mental illness. However, this burden is not fully explored in India...  相似文献   
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A 72-year-old hypertensive man with diabetes had a previously undiagnosed pattern of coronary artery distribution: the ramus intermedius from the left sinus, and the separate origin of the left anterior descending artery, left circumflex artery and right coronary artery from the right sinus. A unique form of branching, a hybrid distribution, was also noted: the left anterior descending artery giving off a right ventricular branch and septals arising from the ramus. No intervention was planned due to the minimal disease observed with angiography and the absence of an interarterial course.  相似文献   
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BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.  相似文献   
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