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OBJECTIVE: To identify any clinical and pathologic features of treatment modalities that are predictive of outcome in patients with epithelioid sarcoma, a rare slow-growing soft tissue tumor most commonly occurring in the distal extremities of young adults. DESIGN: We reviewed the institutional files for cases of epithelioid sarcoma for the period 1956 to 1991 and analyzed the effect of various factors on survival. MATERIAL AND METHODS: Fifty-five cases of epithelioid sarcoma were found, and the relevant clinical, pathologic, treatment, follow-up, and outcome features were assessed. RESULTS: All tumors were treated initially by operative resection. The recurrence rate progressively decreased with increasing aggressiveness of the initial operation; however, no difference was noted in metastatic rate. Overall, the recurrence rate was 38% and the metastatic rate was 47%. At the end of a mean follow-up of 102 months, 69% of patients had no evidence of disease, 27% had died of the disease, and 4% were alive with disease. Increasing tumor size, necrosis of more than 30%, and vascular invasion correlated significantly with a worse prognosis. CONCLUSION: Epithelioid sarcoma should be considered a malignant neoplasm with a significant potential for aggressive behavior, and close follow-up of affected patients should be maintained for many years. Initial treatment should be aggressive in an attempt to prevent recurrence.  相似文献   
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OBJECTIVES--(1) to evaluate regional cerebral blood flow (rCBF) with single photon emission computed tomography and 99mTc-hexamethylpropyleneamine oxime in patients with the idiopathic adult hydrocephalus syndrome (IAHS); (2) to examine regional cerebral blood flow (rCBF), gait, and psychometric functions before and after CSF removal (CSF tap test); (3) to assess abnormalities in subcortical white matter by MRI. METHODS--Thirty one patients fulfilling the criteria for IAHS (according to history and clinical and neuroradiological examination) were studied. Quantified gait measurements, psychometric testing, and rCBF before and after removal of CSF were obtained. Pressure of CSF and CSF outflow conductance were investigated with a constant pressure infusion method. Brain MRI was used to quantify the severity of white matter lesions and periventricular hyperintensities. In IAHS a widespread rCBF hypoperfusion pattern was depicted, with a caudal frontal and temporal grey matter and subcortical white matter reduction of rCBF as the dominant feature. Removal of CSF was not accompanied by a concomitant increase in rCBF. Significant white matter lesions were detected only in a minority of patients by MRI. An altered CSF hydrodynamic state with a higher CSF pressure and lower conductance was confirmed. IAHS is characterised by an abnormal CSF hydrodynamic state, associated with a widespread rCBF reduction with preference for subcortical white matter and frontal-temporal cortical regions. Furthermore in most patients MRI did not show white matter changes suggestive of a coexistent subcortical arteriosclerotic encephalopathy. At least in the idiopathic group of patients with AHS, measurements of rCBF before and after temporary relief of the CSF hydrodynamic disturbance will not provide additional information that would be helpful in the preoperative evaluation but is suggestive of a preserved autoregulation of rCBF.  相似文献   
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In this study,perforated cannulated magnesium(Mg)hip stents were fabricated via modified Mg injection molding and conventional machining,respectively.Additionally,the stent canal was filled with paraffin to simulate injection of biomaterials.The microstructure,mechanical performance,corrosion behavior,and biocompatibility were comparably studied.Scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)showed higher affinity of interstitial element such as oxygen and carbon as consequences of routine molding process.After immersion in SBF,machining stents showed reduced degradation rate and increased deposition of calcium phosphate compared to molding stents.Corrosion resistance was improved via paraffin-filling.Consistently,the hemolysis and in vitro osteoblast cell culture models showed favourable biocompatibility in machining stents compared to molding ones,which was improved by paraffin-filling treatment as well.These results implied that the feasibility of the prepared machining stents as the potential in vivo orthopaedic application where slower degradation is required,which could be enhanced by designing canal-filling injection of biomaterials as well.  相似文献   
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Thermolysin is catalytically inactive in mixtures of 10-15 % acetonitrile in aqueous buffer. Unexpectedly, dilution of the inactive enzyme with acetonitrile leads to complete recovery of the catalytic activity in a similar way to dilution with aqueous buffer. Circular dichroism and fluorescence studies of thermolysin in the same solvent mixtures reveal discontinuous changes in the overall secondary and tertiary protein structure that correlate well with the reversible differences in catalytic activity. The spectra on either side of the minimum activity point are different from each other, a fact indicating that the enzyme may be able to access two active conformations which are thermodynamically stable in different solvent environments.  相似文献   
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A wide variety of lipases remain catalytically active in systems containing high proportions of water-immiscible organic liquids; such reaction mixtures offer several advantages for the industrial application of biocatalysis. The system splits into two or more phases, but in some cases the amount of water is so low that even the polar phase around the enzyme catalyst is far from a dilute aqueous solution. Lipases in such systems are efficient catalysts of synthetic reactions, because two factors can contribute to shifting the position of hydrolytic equilibria: relative solvation of reactants and products, and reduction in the thermodynamic activity of water (aw). Reaction rates can be comparable to those in higher water systems, though may be lower with some forms of catalyst, and depend on the precise water content and hydration history. Where all reactants and products can be transferred via the organic phase, as in the selective transesterification of triacylglycerols in oils and fats, then attractive packed bed reactors may be operated with water only present adsorbed in the catalyst bed. If access to both phases is needed, as in enzymic lipolysis, then a continuous membrane reactor may be useful.  相似文献   
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The recently cloned bumetanide-sensitive Na/K/2Cl cotransporters (ENCC2-3) and thiazide-sensitive Na/Cl cotransporter (ENCC1) have important roles in sodium chloride absorption and secretion, cell volume regulation, ammonium accumulation in medullary interstitium, and ammonium excretion. Genetic mutations of bumetanide-sensitive Na/K/2Cl cotransporters and thiazide-sensitive Na/Cl cotransporter cause the hereditary hypokalemic alkalosis of some Bartter's syndrome and Gitelman's syndrome, respectively. The transporters are sensitive to diuretics and several hormones. Dehydration and acidosis influence the gene expression of ENCC3 but not of ENCC1-2. In contrast, sodium loading increases ENCC2 protein expression in the outer medulla.  相似文献   
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O.N. Sud  P.B. Davies  J. Halling 《Wear》1974,27(2):237-249
The experimentally observed time dependent behaviour of two different rolling bearing assemblies subjected to initial preloads is described for a wide range of operating conditions. It is shown that although the assemblies exhibited very different and apparently complicated behaviour their response, for a given set of conditions, was dependent on only two factors, namely the thermoelastic properties of the system and the manner in which the rate of energy input into the system varied with time. Both assemblies exhibited well defined thermal instability which was determined entirely by these properties.  相似文献   
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