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51.
OBJECTIVE: Defects of the cochlear modiolus have been found to be associated with most cases of large vestibular aqueduct. The clinical significance of these modiolar defects has not been studied previously. The purpose of this article is to correlate clinical (functional) parameters, such as hearing outcomes, with the severity of the radiographic findings in these dysplastic inner ears. STUDY DESIGN: The study design was a retrospective chart review, supplemented with telephone interviews and clinic visits. SETTING: The study was conducted at an academic, tertiary care center. PATIENTS: Thirty consecutive patients with large vestibular aqueducts participated. RESULTS: Scores of modiolar deficiencies yielded inconsistent correlations with hearing loss. Vestibular aqueduct morphology and thickness correlated very strongly with the severity of hearing loss. CONCLUSIONS: These observations support the hypothesis that large vestibular aqueduct-related hearing loss may be caused by transmission of subarachnoid pressure forces into the inner ear. However, the thickness and morphology of the vestibular aqueduct may simply be markers for more subtle cochlear dysplasia manifest by modiolar deficiency.  相似文献   
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In this study, a least squares procedure for calculating the calibration constants of a portable gamma-ray spectrometer using the general inverse matrix method is presented. The procedure weights the model equations fitting to the calibration data, taking into account the variances in the counting rates and in the radioactive standard concentrations. The application of the described procedure is illustrated by calibrating twice the same gamma-ray spectrometer, with two independent data sets collected approximately 18 months apart in the same calibration facility.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized clinico-pathologic entity typically associated with obesity, type II diabetes and hyperlipidemia. It has been noted to recur after orthotopic liver transplantation (OLT). We report four patients who developed de novo NAFLD within 3 months of OLT without the typical predisposing factors of diabetes mellitus or obesity. Three of the four patients underwent OLT for hepatitis C-related cirrhosis, and the other for alcoholic cirrhosis. Examination of the liver explants revealed no evidence of steatosis. No surreptitious alcohol use or a drug-induced process could be identified in these patients. Treatment of recurrent hepatitis C infection in one patient with interferon and ribavirin led to sustained suppression of the viral RNA to undetectable levels, but no improvement in histology or liver enzymes. All four patients had histologic evidence of preservation injury on the initial post-OLT biopsies, but the significance of this finding in relationship to the development of NAFLD is unknown. NAFLD can develop without any of the known predisposing conditions after transplantation, and this raises further questions about the pathogenesis of this condition.  相似文献   
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MRL/MP-lpr/lpr (MRL/lpr) mice have a single mutation (lpr) of the fas apoptosis gene. The mutant mice developed significantly smaller lesions than the wild-type mice at the earlier stage of infection with the intracellular protozoan parasite Leishmania major. However, while all the wild-type mice achieved complete lesion resolution, the disease in the mutant mice progressed inexorably. The mutant mice had more IL-12 and nitrite/nitrate in the serum than wild-type mice following infection. Lymphoid cells from infected MRL/lpr mice produced more IFN-gamma but less IL-4 and IL-5 than cells from MRL-+/+ mice. Peritoneal macrophages from the mutant mice also produced more IL-12 and NO after stimulation with LPS. Thus, Fas expression is essential for resistance against leishmaniasis, and Fas-mediated apoptosis may form an integral part of the Th1-mediated microbicidal function.  相似文献   
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Within 3 hours, 10 healthy male volunteers were infused 500 ml of a 5 percent emulsion in which 25 percent of the fat proportion had been replaced by MCT-fats. As expected, the ketone body concentration in the blood rose, while pyruvate remained constant and lactate dropped. The results show that, basically, a MCT-containing fat infusion is suited for parenteral nutrition and, because of their specific properties, medium chain triglycerides may be used as rapid energy donators.  相似文献   
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OBJECTIVE: Hyperamylasemia with a presumptive diagnosis of acute pancreatitis has been reported following organophosphate poisoning but there are no large-scale studies incorporating more specific diagnostic criteria. METHODS: Retrospective review of the medical records of 159 patients with a diagnosis of organophosphate poisoning over 3 years. Serum amylase, pancreatic amylase, salivary amylase, lipase and cholinesterase levels, and the clinical manifestations were analyzed. RESULTS: Serum amylase data was available for 121 of the 159 study patients. Hyperamylasemia (amylase > or = 360 U/L) was found in 44 patients (36%). Lipase was measured in 28 patients with hyperamylasemia; 9 of 28 had hyperlipasemia (lipase > or = 380 U/L). The finding of hyperamylasemia was closely related to clinical severity and presence of shock. A presumptive diagnosis of painless acute pancreatitis was diagnosed by hyperlipasemia associated with hyperamylasemia, clinical severity, serum LDH, and leukocyte counts. Two patients with presumptive pancreatitis died. Shock, coma, and hypoalbuminemia were the factors predicting fatality. CONCLUSIONS: Hyperamylasemia is frequent in severe organophosphate poisoning. However, hyperamylasemia is not synonymous with acute pancreatitis and pancreatic amylase is not a reliable parameter in the diagnosis of organophosphate-induced pancreatitis due to its low sensitivity and specificity. Lipase assay is indicated in patients with hyperamylasemia for early diagnosis of pancreatitis. Proper image studies and even pathological examination are also needed to confirm the extent of pancreatic injury. With prompt diagnosis and appropriate treatment, a complete recovery can be anticipated unless the patient has otherwise unrelated complications.  相似文献   
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BACKGROUND: The optimal period of conservative treatment for adhesive small bowel obstruction remains controversial. This study sought to determine whether a 24-h abdominal radiograph after oral Urografin is a reliable indicator for operation in patients with adhesive small bowel obstruction. METHODS: One hundred and sixty-one patients who suffered from adhesive intestinal obstruction without clinical evidence of strangulation or gangrene underwent a Urografin study. Some 40 ml Urografin mixed with 40 ml distilled water was administered either orally or via a nasogastric tube to each patient. Serial plain abdominal radiographs were taken 4, 8, 16 and 24 h later. If an earlier plain radiograph showed that contrast medium had reached the ascending colon, subsequent radiographs were not taken. RESULTS: Contrast medium reached the colon within 24 h in 112 patients (70 per cent). These patients were all treated successfully with non-operative methods. Contrast medium was not observed in the colon within the first 24 h in 49 patients (30 per cent). Operation was performed in 47 of these patients and non-operative treatment was given in two. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Urografin reaching the colon within 24 h as an indicator for non-operative treatment were 98, 100, 99, 100 and 96 per cent respectively. CONCLUSION: All patients with evidence of Urografin reaching the colon within 24 h were treated successfully with non-operative methods. The results of this prospective study suggest that patients with adhesive intestinal obstruction in whom contrast medium fails to reach the colon within 24 h should receive prompt surgical intervention.  相似文献   
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OBJECTIVE: To evaluate the accuracy and cost-efficacy of the diagnostic procedure and treatment for renovascular hypertension. SETTING AND PATIENTS: A total of 519 patients referred to the university clinic for hypertension were screened for renovascular hypertension with 405 captopril challenge tests (CCT) and 450 captopril renographies (CRG). INTERVENTIONS: Abdominal angiography was performed on 84 patients for positive screening. Fifteen patients underwent angiography for a sole suspicious clinical presentation. The angiography revealed 17 renal artery stenoses and five occlusions in 20 patients. Fifteen technically successful angioplasties and three nephrectomies were performed. RESULTS: In the patients who underwent angiography, CCT had a specificity of 39% and a sensitivity of 67% for renovascular hypertension. CRG had a sensitivity of 100% and a specificity of 68%. In the whole study population, the estimated specificity of CCT was 88% and that of CRG 95%. Invasive treatment reduced systolic/diastolic blood pressure from 157/99 to 140/87 mmHg and the number of antihypertensive drugs used from 2.6 to 1.4 in 16 patients (mean age 49 years). Angiotensin converting enzyme (ACE) inhibition was effective in four elderly patients. Cost-efficacy analysis Screening with CRG and invasive treatment cost US$15400 per successful invasive treatment Equally effective pharmacological treatment would have cost US$10400. Limiting the screening with CRG to the 173 patients with no obvious renal parenchymal disease and with hypertension at a younger age (< or =30 years) or unresponsive to two antihypertensive drugs (diastolic blood pressure > 90 mmHg) would have yielded a prevalence of 12% and missed only one elderly patient who responded to ACE inhibition. The limited screening, along with invasive treatment, would have cost US$7300 per patient CONCLUSIONS: CRG is superior to CCT for screening of renovascular hypertension. Screening with CRG is cost-effective when limited to patients with no obvious renal parenchymal disease and with hypertension that does not respond to two antihypertensive drugs or is detected in patients no older than 30 years.  相似文献   
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