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101.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
102.
103.
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.  相似文献   
104.
Anti-Sc1 was detected in a gravida-2 patient at 12 weeks' gestation. At 29 weeks, the antibody was found to be of the IgG3 subclass with a titer of 16, score 36, by the indirect antiglobulin test, and it produced 7 percent lysis by antibody-dependent cellular cytotoxicity (ADCC) assay, a finding that suggested an unaffected fetus. The titer remained constant throughout the pregnancy, as did the IgG subclass and activity in the ADCC assay. At delivery of the full-term infant, the cord hemoglobin was 13.5 g per dL and the direct antiglobulin test was positive (3+) with anti-IgG. The infant did not require transfusion. A sample taken 9 weeks after delivery showed 44 percent lysis in the ADCC assay. The anti-Sc1 titer was 32, score 65.  相似文献   
105.
AIM: We evaluated the effects of an alpha-glucosidase inhibitor, acarbose, on glucose homoeostasis during postprandial exercise in Type 1 diabetic subjects. METHODS: Seven Type 1 diabetic subjects with good glycaemic control on ultralente-regular insulin were randomized in a single blind cross-over study to acarbose 100 mg or placebo taken with a mixed meal (600 kcal, 75 g carbohydrates), followed 90 min later by 30 min of exercise at 50% maximum aerobic capacity. Glucose turnover was measured by tracer (d-[6,6,2H2]glucose) methodology, and intestinal glucose absorption was quantified using carbohydrate polymers labelled with [13C]glucose. RESULTS: Acarbose resulted in a significant decrease in the postprandial glycaemic rise (mean +/- SEM 2.9 +/- 0.6 vs. 5.0 +/- 0.7 mmol/l; P < 0.005) and in the glycaemic nadir during exercise (- 0.8 +/- 0.6 vs. 0.9 +/- 1.3 mmol/l below baseline; P < 0.05). Total glucose appearance increased similarly under the two treatments during the postprandial (27.0 vs. 27.9 micromol per kg per min) and exercise (33.9 vs. 33.5 micromol per kg per min) periods. Mean glucose absorption was significantly delayed by acarbose (7.8 vs. 10.2 micromol per kg per min; P < 0.02), but was compensated by the lack of postprandial suppression of hepatic glucose production (106% of basal hepatic glucose production vs. 81%; P < 0.006). Episodes of hypoglycaemia were no different (three vs. six). CONCLUSION: These results indicate that, in Type 1 diabetic subjects, acarbose results in a better glycaemic profile during postprandial exercise and suggest that it could lead to a lower risk of exercise-induced hypoglycaemia due to delayed glucose absorption and less suppression of hepatic glucose production.  相似文献   
106.
The purpose of this study was to develop primary cultures of human chorion laeve cells and examine certain aspects of steroid metabolism during culture. Tissues obtained by elective cesarean section at term (38-40 weeks) were dispersed with collagenase. Cells were isolated on Percoll gradients at the interface between 20% and 40% Percoll and examined in primary culture for up to 1 week. Cultures were carried out in chemically defined media supplemented with 10% or 0.1% fetal calf serum (FCS). The morphological and biochemical properties of the cells were different in the two systems. In 0.1% FCS, cells formed clumps of tissue within 16 h of plating, and there was no cell replication. In contrast, in 10% FCS, the cells formed a carpet of tissue and reached confluence after 5 days in culture, resulting in increased DNA and protein content and thymidine incorporation in the dishes. Three steroidogenic enzymes were studied during culture: alkyl steroid sulfatase, estrogen sulfatase and 3 beta-hydroxysteroid dehydrogenase. The sulfatases had higher activities in 0.1% than in 10% FCS, and their activities decreased markedly during the culture period. In contrast, 3 beta-hydroxysteroid dehydrogenase activity was higher in 10% FCS than in 0.1% FCS. Activity remained constant during the culture period in 0.1% FCS and increased in 10% FCS. In the latter system this increase resulted in the enzyme maintaining a constant specific activity during culture. These studies describe two viable systems of chorion laeve cells in primary culture, which may be valuable for studying long term and/or subtle effects on various metabolic aspects of this tissue.  相似文献   
107.
Complications of epidural anesthesia: MR appearance of abnormalities   总被引:5,自引:0,他引:5  
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108.
The first evidence that the liver can afferently contribute to regulatory activities comes from studies on regulation of food intake. The hepatic afferent pathway has been shown to be responsive to glucoprivic as well as lipoprivic stimuli. Similarly to regulation of food intake, it has been reported that the liver may afferently contribute to the metabolic regulation of exercise. The best reported evidence of this view is the observation that the decrease in insulin and the increase in glucagon and noradrenaline levels during exercise are diminished in hepatic vagotomized rats (Lavoie et al., 1989). The concept behind these observations is that the liver, through the existence of hepatic glucoreceptors, is responsive to a decrease in glycogen content or to some metabolites of the glycolytic chain related to liver glycogen content. There is also some evidence that lipids in the liver may have some regulatory impact inside and outside the liver. Recent interest in looking at lipid metabolism in liver has been spurred by the observation that the increased flux of lipids through the hepatic portal vein has been associated with increased risks of metabolic and cardiovascular abnormalities. To explore this avenue, a 10% triglyceride emulsion was infused into either the portal or a peripheral vein of rats for 48 hrs while another group of rats was acutely infused for 2 hrs into the portal vein. The results indicate that all of these lipid infusions resulted in an increase in liver lipid infiltration, which may be associated with the development of a state of hepatic and peripheral insulin resistance.  相似文献   
109.
There is substantial clinical and experimental evidence to suggest that ammonia toxicity is a major factor in the pathogenesis of hepatic encephalopathy associated with subacute and chronic liver disease. Ammonia levels in patients with severe liver disease are frequently found to be elevated both in blood and cerebrospinal fluid (csf). Hepatic encephalopathy results in neuropathological damage of a similar nature (Alzheimer type II astrocytosis) to that found in patients with congenital hyperammonemia resulting from inherited defects of urea cycle enzymes. Following portocaval anastomosis in the rat, blood ammonia concentration is increased 2-fold, and brain ammonia is found to be increased 2–3-fold. Administration of ammonia salts or resins to rats with a portocaval anastomosis results in coma and in Alzheimer type II astrocytosis. Since the CNS is devoid of effective urea cycle activity, ammonia removal by brain relies on glutamine formation. Cerebrospinal fluid and brain glutamine are found to be significantly elevated in cirrhotic patients with encephalopathy and in rats following portocaval anastomosis. In both cases, glutamine is found to be elevated in a region-dependent manner. Several mechanisms have been proposed to explain the neurotoxic action of ammonia. Such mechanisms include: (i) Modification of blood-brain barrier transport; (ii) alterations of cerebral energy metabolism; (iii) direct actions on the neuronal membrane; and (iv) decreased synthesis of releasable glutamate, resulting in impaired glutamatergic neurotransmission.  相似文献   
110.
SUMMARY Four cases of primary meningococcal conjunctivitis in children are reported. This represents an incidence of 2% of patients presenting with conjunctivitis to a paediatric A&E department. All were initially treated with topical chloramphenicol, followed by systemic rifampicin once the diagnosis had been established. No ocular or systemic complications developed, nor recolonisation of the conjunctiva or colonisation of the nasopharynx at follow-up (1–2 years).  相似文献   
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