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Transbronchial needle aspiration (TBNA) is a valuable, minimally invasive procedure for diagnosing and staging lung cancer in patients, but it is underutilized by practicing pulmonologists. To assess the approach to TBNA of current pulmonary Fellows, we recorded their computerized interactive responses during the 1995 American College of Chest Physicians Fellows' Conference. Among 109 Fellows attending, only 10% reported that they routinely (> or = 85% of cases) performed TBNA to diagnose or stage malignant disease, and 40% noted that they rarely (< or = 5% of cases) performed it. They estimated their diagnostic TBNA yields in patients with mediastinal cancer as follows: > or = 80% by 2% of Fellows; between 25% and 80% by 54% of Fellows; and < 25% by 45% of Fellows. They noted that the main limitations of TBNA at their institutions were suboptimal bronchoscopy technique (30%), technician support (1%), cytopathology support (14%), all of these factors (25%), or the belief that TBNA is not useful (30%). TBNA is currently underutilized and/or underemphasized at bronchoscopy training programs. Major modifications of Fellow experiences are necessary if TBNA is to impact optimally on patient management.  相似文献   
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The causes of post operative pyrexia in an orthopaedic unit was studied prospectively in 520 patients who underwent surgery. Two hundred patients (38.4%) developed postoperative pyrexia as defined by having recorded high temperatures of over 38 degrees C on two occasions within 24 hours (excluding the first 24 hours post-operatively). The commonest causes of post-operative pyrexia were wound infection in 70 (13.4%), respiratory tract infections in 40 (7.6%) and malaria in 30 (5.7%) patients, while other causes were urinary tract infection in 20 (3.8%), thrombophlebitis in 15 (2.8%) and deep vein thrombosis in 15 (2.8%) of the patients; while ten (1.9%) patients had pyrexia of undetermined cause despite exhaustive clinical and laboratory workup. The other associated conditions in patients who developed pyrexia were diabetes mellitus in 20 (3.8%), HIV seropositivity and malignancy in 30 (5.7%) and six (1.1%) patients, respectively.  相似文献   
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The paper describes a clinical case of the cerebral hyperperfusion syndrome, a rare complication of carotid endarterectomy. The syndrome appeared as the generalized convulsive syndrome in the patient in the early postoperative period. In the context of clinical observation, the results of analysis of the literature are presented and the pathogenesis, diagnosis, therapy, and prevention of the cerebral hyperperfusion syndrome considered.  相似文献   
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The application of ATP in micromolar concentrations to the macrophages results in a biphasic response in the form of the short-time depolarization followed by a rather long hyperpolarization, the corresponding inward and outward macroscopic currents being observed. The ATP-induced hyperpolarization is accompanied by changes in current kinetics, I/V-curves pattern and shifting in the reversal potential. Such changes may be explained by a supposition that ATP activates an additional fraction of potassium channels with characteristics other than those in cells with initially low value of membrane potential. The data available are suggestive that in resting cells the inward rectification potassium conductance may dominate, whereas during ATP-induced hyperpolarization a certain type of Ca(2+)-dependent potassium conductance prevails. A rather high membrane potential in some part of macrophages, not treated with ATP, may be attributed to the latter type of conductance.  相似文献   
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The proliferation of glioma cells requires cholesterol, which could be provided by synthesis within the cells or by uptake of cholesterol esters in particles of Low Density Lipoprotein (LDL). Cholesterol esters and cholesterol were therefore analysed in human glioma tissue, its surrounding areas and serum from 40 patients. The analyses revealed an increased concentration of cholesterol esters up to 100 times (0.1-10 mumol/g) in both tumour-tissue and surrounding areas compared with control material (< 0.1 mumol/g). The analyses also demonstrated that cholesterol esters in tumour tissue eminated mainly from serum. The cholesterol concentrations were significantly lower in tumour tissue compared with surrounding areas as expected. These results indicate that tumour cell proliferation utilises serum derived cholesterol esters presumably carried by LDL particles.  相似文献   
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The hmc operon of Desulfovibrio vulgaris subsp. vulgaris Hildenborough consists of six genes (hmcA to hmcF) that encode structural components of the high-molecular-mass cytochrome redox protein complex (the Hmc complex). Two genes (rrf1 and rrf2) encoding regulatory proteins are present downstream of hmcF. Expression of the hmc operon, monitored by incubating protein blots with HmcA-specific or HmcF-specific antibodies, was found to be highest when hydrogen was the sole electron donor for sulfate reduction. Use of lactate or pyruvate as electron donor reduced expression of the hmc operon. A mutant with a deletion of the rrf1 and rrf2 genes was generated with the sacB mutagenesis method. This mutant overexpressed the hmc operon approximately threefold. It grew more rapidly than the wild type when hydrogen was used as the electron donor for sulfate reduction, but more slowly than the wild type when lactate was used. The results indicate that a physiological function of the Hmc complex is in electron flow from hydrogen to sulfate. At least one redox carrier is shared competitively by the hydrogen and lactate oxidation pathways in D. vulgaris.  相似文献   
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