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61.
The records of 60 patients with gallbladder carcinoma (GBC) operatively treated between 1966 and 1993 at Belen Hospital, Trujillo, Perú, were retrospectively reviewed. The ratio of men to women was 1:7.5 and the average of age was 61 years. The accuracy of ultrasonography and oral cholecystograms for the specific diagnosis was 21% and 0% respectively. The surgical procedures employed were simple cholecystectomy (n = 56), right hepatectomy (n = 2). Whipple operation (n = 1) and extended cholecystectomy (n = 1), and our resectability rate for GBC is currently 50%. Simple cholecystectomy was a potentially curative surgical procedure in patients with in situ cancer (stage O) and early GBC (stage 1). In hospital mortality was 11.6% and 5-year survival rate for the total series was 15%. Gallstones were present in 95% of patients and most tumors (58%) had grown by diffuse infiltration or were associated with empyema (38%). Tumor stage, depth of invasion, tumor grade histologic type were all predictive of patient outcome. This report reinforces the difficulty in diagnosis and the poor prognosis for patients with GBC. We hold the view that more radical approaches for invasive cancers will enhance the operative results.  相似文献   
62.
Ten families living in Shenyang city with multiple cases of essential hypertension were studied by HLA haplotype analysis. They were selected strictly in accordance with the methods of sibling pair analysis and lods analysis. The obtained ratio of HLA haplotype sharing among affected siblings were 28.6%(2): 52.4%(1): 19.0%(0), P > 0.9. It is indicated that the haplotype shared randomly among affected siblings. The results of Lods analysis were Q = 0.40, Lods = 0.046, Pr = 1.112. These results showed that there is no evidence of patients with essential hypertension susceptible to gene linked with HLA.  相似文献   
63.
This study was undertaken to investigate the possible association between thrombosis and infection using an in vitro test model in which fresh bovine blood was recirculated through test conduits (3.5 mm inner diameter) containing stent-like devices. Anticoagulation was adjusted so that the recirculating blood deposited thrombi on the stent to cause gradual occlusion, thus impeding the flow. Four stent-like devices were placed in separate conduits in each experiment, and blood was recirculated with the help of pneumatically driven ventricles. Flow through these conduits was monitored by ultrasonic flow detection. To quantitate bacterial interaction with thrombi, Staphylococcus epidermidis (15E10(9)) was labeled with 111Indium-oxine and added to the blood. Experiments lasted until the flow in the test conduits dropped to 10% of the starting flow. During this recirculation, as flow gradually decreased, one stent was taken out when flow was still at 100%, the second at 75%, the third at 50%, and the fourth at 10% of the starting flow. The number of bacteria associated with the thrombus was measured by gamma counting. The following observations were made: 1) the amount of thrombus increased with time in all experiments (this was confirmed in separate experiments by using autologous 111Indium labeled platelets); 2) bacterial adhesion showed a concomitant increase as thrombus size increased (this was confirmed by using 111Indium labeled bacteria), and 3) bacterial incorporation into the thrombus occurred regardless of whether they were viable or pretreated with the antibiotic rifampin. These observations suggest that as thrombi develop, they may preferentially attract micro-organisms. This suggests that devices with adherent thrombi may have greater susceptibility for infection.  相似文献   
64.
The influence of the bolus injection rate of propofol on its cardiovascular effects has not been extensively studied. We therefore examined the influence of the injection rate of i.v. bolus doses of propofol on its acute cardiovascular effects and peak blood concentrations in seven chronically instrumented sheep. Each received i.v. propofol (200 mg) over 2 min (slow injection) and 0.5 min (rapid injection) on separate occasions in random order. The rapid injection was associated with more profound decreases in mean arterial blood pressure than slow injection (35.7% vs 23.7% maximal reductions from baseline, respectively; P = 0.02). There were no significant differences between the injection rates for peak reductions in myocardial contractility, increases in heart rate, or degree of respiratory depression. Concurrently, the rapid injections were associated with significantly higher arterial (26.9 vs 11.9 mg/L) propofol concentrations in a manner consistent with indicator dilution principles. There were no differences in the peak coronary sinus concentrations between the injection rates. We conclude that the rapid injection of propofol in the context of the induction of anesthesia produced significantly higher peak arterial propofol concentrations and suggest that it is these higher concentrations that produced relatively greater reductions in arterial blood pressure from rapid injections. Implications: Propofol is injected into a vein to initiate anesthesia. It can cause a rapid decrease in blood pressure, which may be dangerous to the patient. We examined the effect of rapid and slow injection rates of propofol in sheep and found that rapid injection caused a greater decrease in blood pressure. This was because rapid injection caused higher concentrations of propofol in the blood immediately after the injection. We believe that if the same processes occur in humans, there may be little advantage in injecting propofol rapidly.  相似文献   
65.
Pelizaeus-Merzbacher disease (PMD) is a dysmyelinating disease resulting from mutations, deletions, or duplications of the proteolipid protein (PLP) gene. Distinguishing features of PMD include pleiotropy and a range of disease severities among patients. Previously, we demonstrated that, when expressed in transfected fibroblasts, many naturally occurring mutant PLP alleles encode proteins that accumulate in the endoplasmic reticulum and are not transported to the cell surface. In the present communication, we show that oligodendrocytes in an animal model of PMD, the msd mouse, accumulate Plp gene products in the perinuclear region and are unable to transport them to the cell surface. Another important aspect of disease in msd mice is oligodendrocyte cell death, which is increased by two- to threefold. We demonstrate in msd mice that this death occurs by apoptosis and show that at the time oligodendrocytes die, they have differentiated, extended processes that frequently contact axons and are expressing myelin structural proteins. Finally, we define a hypothesis that accounts for pathogenesis in most PMD patients and animal models of this disease and, moreover, can be used to develop potential therapeutic strategies for ameliorating the disease phenotype.  相似文献   
66.
Rice bacterial artificial chromosome clones containing centromeric DNA were isolated by using a DNA sequence (pSau3A9) that is present in the centromeres of Gramineae species. Seven distinct repetitive DNA elements were isolated from a 75-kilobase rice bacterial artificial chromosome clone. All seven DNA elements are present in every rice centromere as demonstrated by fluorescence in situ hybridization. Six of the elements are middle repetitive, and their copy numbers range from approximately 50 to approximately 300 in the rice genome. Five of these six middle repetitive DNA elements are present in all of the Gramineae species, and the other element is detected only in species within the Bambusoideae subfamily of Gramineae. All six middle repetitive DNA elements are dispersed in the centromeric regions. The seventh element, the RCS2 family, is a tandem repeat of a 168-bp sequence that is represented approximately 6,000 times in the rice genome and is detected only in Oryza species. Fiber-fluorescence in situ hybridization analysis revealed that the RCS2 family is organized into long uninterrupted arrays and resembles previously reported tandem repeats located in the centromeres of human and Arabidopsis thaliana chromosomes. We characterized a large DNA fragment derived from a plant centromere and demonstrated that rice centromeres consist of complex DNA, including both highly and middle repetitive DNA sequences.  相似文献   
67.
68.
A pedigree of megalocornea manifested many of the characteristic features as well as some less common features of the disorder. Endothelial specular microscopy of affected patients disclosed normal endothelial cell densities and morphologic characteristics and increased total endothelial cell populations, suggesting a process of total corneal hyperplasia. In contrast, unpublished data indicate diminished densities in congenital glaucoma, a finding more consistent with corneal distention. We conclude that specular microscopy may be of value in differentiating the two disorders, although larger series are necessary for confirmation.  相似文献   
69.
Free amino acid determinations in the cerebrospinal fluid of patients with Parkinson's disease or other extrapyramidal disorders showed that in both groups most amino acids were increased. Significantly increased amino acids were neutral and basic amino acids. Amino acid clusters were present and corresponded with the grouping of amino acids in accordance with amino acid transport systems. The amino acids within the clusters showed a remarkable degree of correlation, and there was a notable correlation between the clusters both in the parkinsonian group and in the group of extrapyramidal disorders, but not in a control group. Our data suggest that in a number of extrapyramidal disorders, Parkinson's disease included, a more generalized abnormality exists than neuronal loss only and, in addition, that patients with these neurologic conditions have a common biochemical defect in their amino acid transport systems.  相似文献   
70.
Multiple choice questions used in continuing medical education may require characteristics different from those used in tests and examinations. The questions of three continuing education exercise were assessed by 48 board certified family physicians. Each physician answered one third of the questions and then judged them on usefulness in patient management, as discriminators of quality of medical care, and on educational value. The relevance of each question was determined by a composite index based on these factors. The content of each question was independently analyzed by three physicians. Relevant questions tended to be those concerned with surgery, symptoms, and management, and those requiring more than simple factual recall. Questions on office management or concerning specific diagnoses were considered less relevant. Neither the manner of asking the question nor the severity of the illness appeared to influence relevance. This information should benefit those developing continuing education programs for family physicians, especially those designed for self-administered individual learning.  相似文献   
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