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991.
The purpose of the study was to investigate the prevalence ofanaemia in adults in rural and urban areas of Tanzania withparticular respect to males. A total of 8579 subjects aged 15years and over were investigated in 8'rural villages from 3regions and another 1458 in 2 urban areas in Dar es Salaam.Of males, 29.8% were anaemic (Hb<13 g/dl) in the most prosperousrural area, 47.9% in the city, and 73.5% and 79.9% in the twopoorer rural areas. In the latter, 25.1% and 26.3% had valuesbelow 11 g/dl. Equivalent values for females were 25.8%, 62.6%(urban), 80.5% and 80.1% (Hb<12 g/dl) with 2.1%, 16.5% (urban),16.9% and 26.8% less than 10 g/dl. Pregnant women (n = 257)had significantly lower Hb levels than non-pregnant females.In males anaemia was more prevalent in the old. The prevalenceof anaemia was higher in the poorer rural areas than in mostpreviously reported studies in Africa. In particular our resultsemphasize that anaemia is a major problem in males in Tanzaniaand could have a significant economic and health impact.  相似文献   
992.
Extracorporeal membrane oxygenation (ECMO), a lifesaving procedure in neonates with severely impaired lung function, requires ligation of the right common carotid artery. In an investigation of the collateral pathways that maintain perfusion of the brain after right common carotid artery ligation, ten infants were studied with color Doppler imaging during and after ECMO. The circle of Willis was seen in all infants, and in every case there was retrograde flow in the distal internal carotid artery and the proximal (A1) segment of the anterior cerebral artery. Bilateral flow in the middle cerebral arteries and in distal branches of the anterior cerebral arteries was also seen, documenting flow to both cerebral hemispheres.  相似文献   
993.
Halothane stimulated basal adenylate cyclase activity in rat cardiac membranes. Maximal stimulation (54%) was obtained after equilibrating the membranes with 2% halothane. Halothane did not affect the fractional stimulation of adenylate cyclase activity produced by either forskolin or isoproterenol. However, halothane decreased carbamylcholine inhibition of adenylate cyclase activity stimulated by both forskolin and isoproterenol. Maximal depression of carbamylcholine inhibition of stimulated cyclase activity was obtained after equilibration with 1% halothane. These results are consistent with evidence from ligand binding studies and indicate that halothane disrupts muscarinic receptor-G-protein interactions.  相似文献   
994.
995.
Palliation of pancreatic cancer using electrolytic ablation   总被引:1,自引:1,他引:0  
Background: Inoperable pancreatic cancer has a dismal prognosis. Palliation involves either stenting or surgical bypass. Stenting does not relieve gastric outlet obstruction, and surgical bypass is a major procedure. A minimally invasive procedure is needed that relieves both gastric outlet and biliary obstruction, with the potential for relieving pain. Methods: In an experimental model, pancreatic electrolysis was investigated. The pancreatic duct was cannulated via a transduodenal approach with an electrode catheter. In 6 animals an electrolytic "lesion" was created using a direct current generator. Six animals were controls. The local and systemic effects of electrolysis were assessed using histological and biochemical parameters. Results: The pancreatic duct was cannulated in all animals and treatment was uneventful. Electrolytic lesions comprised a central area of necrosis with a sharp demarcation between necrotic and viable pancreas. All animals developed transient hyperamylasemia after electrolysis. There was no significant difference between treatment and controls. Importantly, no animal had clinical, biochemical, or histological evidence of pancreatitis. Conclusions: This experimental study suggested that electrolytic palliation of inoperable pancreatic cancer via the gastrointestinal tract is potentially safe. In patients, this treatment could be performed during endoscopic retrograde cholangiopancreatography and may have therapeutic advantages when compared to stenting or biliary bypass.  相似文献   
996.
Growth hormone predicts bone density in elderly women   总被引:1,自引:0,他引:1  
Evidence is accumulating that the risk of osteoporosis may be influenced by environmental factors during intrauterine and early postnatal life; such programming might be mediated through modification of the GH/IGF-1 axis during critical periods in its development. To address this issue, we explored the relationships among birth weight, circulating GH profile, bone density, and bone loss rate in a group of British women. The study population consisted of 38 women 60-75 years old resident in Hertfordshire for whom detailed birth records were available. Twenty-four-hour circulating GH profiles were obtained during an inpatient stay on a metabolic ward, after an overnight rest. The circulating profile of GH was characterised by estimating the peak, median, trough, and total concentrations from 72 samples measured sequentially over 24 h in each subject. Bone mineral density was assessed at the lumbar spine and femoral neck at baseline and at follow-up 4 years later. Lumbar spine bone mineral content (BMC) and density (BMD) were positively associated with all measures of GH concentration, although relationships were strongest for BMC with trough GH (r = 0.47, P < 0.01). Associations persisted after adjustment for age, body mass index, smoking, alcohol consumption, physical activity, and osteoarthritis score in multiple regression models. However, associations of GH concentration with femoral neck BMC were weak, and there was no association between any measure of GH concentration and bone loss at either site. Total (integrated) daily GH concentration tended to increase (P = 0.08) with rising birth weight, while IGF-1 concentration fell (P = 0.05) with rising birth weight, suggesting a role for the GH/IGF-1 axis in the programming of adult bone mass among women.  相似文献   
997.
998.
Gray scale ultrasound of the scrotum   总被引:2,自引:0,他引:2  
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999.
1000.
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