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Primary lymphedema tarda is considered to be a congenital disease with delayed manifestations. We report a case of isolated lymphedema of the left upper extremity in an 88-year-old African-American male. The diagnosis of lymphedema was confirmed by lymphoscintigraphy, and appropriate diagnostic studies were done to rule out other known causes of lymphedema. Lymphoscintigraphic findings were consistent with idiopathic primary lymphedema. During the course of investigations, the patient was found to have adenocarcinoma in situ of the sigmoid colon with no evidence of metastatic spread. Based on the available data, we were unable to establish a causative relationship between colonic carcinoma and lymphedema in our patient. Therefore, this case can best be described as a case of Idiopathic primary lymphedema tarda. We emphasize the use of histopathologic examination in the diagnostic algorithm to rule out underlying malignant process only in patients with radionuclide findings suggestive of secondary lymphedema with no obvious etiology.  相似文献   
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OBJECTIVES: Peer review of trauma deaths can be used to evaluate the efficacy of trauma systems. The objective of this study was to estimate teh proportion of preventable trauma deaths and the factors contributing to poor outcome using peer review in a tertiary care hospital in a developing country. METHODS: All trauma deaths during a 2-year period (1 January 1998 to 30 December 1998) were identified and registered in a computerized trauma registry, and the probability of survival was calculated for all patients. Summary data, including registry information and details of prehospital, emergency room, and definitive care, were provided to all members of the peer review committee 1 week before the committee meeting. The committee then reviewed all cases and classified each death as preventable, potentially preventable, or non-preventable. RESULTS AND CONCLUSION: A total fo 279 patients were registered in the trauma registry during the study period, including 18 trauma deaths. Peer review judged that six were preventable, seven were potentially preventable, and four were non-preventable. One patient was excluded because the record was not available for review. The proportion of preventable and potentially preventable deaths was significantly higher in our study than from developed countries. Of the multiple contributing factors identified, the most important were inadequate prehospital transfer, limited hospital resources, and an absence of integrated and organized trauma care. This study summarizes the challenges faced in trauma care in a developing country.  相似文献   
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Asbestos fibers are well known environmental carcinogen, however, the underlying mechanisms of their action have still not clearly been identified. Asbestos is capable of depleting glutathione and generating reactive oxygen species (ROS), which are important mediators of damage in biological system. Asbestos-induced mutagenecity, may be mediated by the generation. It is known that a number of scavengers and antioxidants attenuate asbestos-induced ROS release. Furthermore, it is known that garlic, contains numerous sulfur compounds and glutathione precursors which act as antioxidants and also demonstrate anticarcinogenic properties. The aim of this study was to investigate whether garlic extract has any influence on asbestos-mediated genotoxicity. As an assay system, we applied the micronucleus assay, sister chromatid exchanges, and chromosomal aberrations with human peripheral blood lymphocytes, which has already been used to analyze the genotoxicity of asbestos fibers. Our results indicate that garlic extract, when administered to the lymphocytes cell culture simultaneously with chrysotile reduced the rates of micronucleus formation, sister chromatid exchanges, and chromosomal aberrations significantly. We conclude that garlic extract may be an efficient, physiologically tolerable quencher of asbestos-mediated genotoxicity.  相似文献   
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Local drug delivery by coronary stents is of current research interest. Organ culture of human vascular tissue is a model of intimal hyperplasia. We report an ex vivo organ culture model of stented vessels. This allows stent-artery interactions to be studied in living tissue. The recognized anti-restenosis agent paclitaxel was chosen to test the organ culture model. Mammary artery specimens were cultured 'closed' (i.e. without opening them flat) for 72 h. Phosphocholine-coated stents, half of them loaded with the anti-restenosis drug paclitaxel, were implanted. The absorption and elution characteristics of paclitaxel were established. Artery tissue remained viable at 72 h when cultured closed, despite stent implantation. Specimens developed smooth muscle cell proliferation. The stents absorbed up to 127+/-29 microg of paclitaxel, with a biphasic elution curve. A mean of 13% of the absorbed paclitaxel remained after a 24 h perfusion. In mammary artery, these paclitaxel stents reduced or abolished smooth muscle cell proliferation compared with controls. This model allows the effects of stenting on human arterial tissue to be studied for at least 72 h, long enough to demonstrate effects on smooth muscle cell proliferation. Phosphocholine-coated stents absorb adequate doses of paclitaxel, which is eluted gradually, inhibiting muscle cell proliferation. Such an organ culture model of stented mammary artery will provide useful data in addition to that from animal or cell culture models of drug-eluting stents.  相似文献   
46.
Epidemiological studies of workers in weaving units in carpet industries have shown relationships between the airborne dust concentrations and pulmonary ill health. Therefore, to predict the health risk of carpet weavers, this preliminary experiment was conducted to evaluate the effect of carpet dust (knotted, tufted) on cellular and biochemical mediators considered as potential biological markers of lung injury. Lung cytoplasmic (lactate dehydrogenase, LDH), lysosomal (acid phosphatase, ACP), type II (alkaline phoshatase, ALP) and Clara-cell marker enzymes (gamma-glutamyl transferase, GGT) were monitored in rat cell-free lung lavage (BAL) during postexposure days 1, 4, 8, and 16. Furthermore, lung microsomal cytochrome P-450 (CYP450) and Clara-cell secretory protein (CC16) content in BAL was also evaluated. These pulmonary marker enzymes were significantly elevated during the postexposure period over the respective untreated control; however, tufted carpet dust shows more responses than knotted carpet dust. Lung CYP450 content was reduced significantly at early days; the pattern shows the reoccurrence of CYP450 content in the later stage of postexposure to carpet dust. Clara-cell secretory protein in BAL shows decline in the carpet-treated group; however, tufted carpet shows more decline than knotted carpet. Thus, reduction in CC16 level may have important implication in the development of chronic lung inflammation and diseases. Present investigation found that modulation of these cellular marker enzymes is clear evidence of pulmonary damage caused by exposure to carpet dust.  相似文献   
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M I Qamar  A E Read 《Gut》1986,27(8):991-992
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Escherichia coli is considered to be the main causative agent of urinary tract infections (UTIs). The primary objective of this study was to investigate the spectrum of five virulence factors among drug-resistant clinical E. coli isolates associated with pyelonephritis and cystitis. A total of 101 samples were positive for E. coli (42 from pyelonephritis cases and 59 from cystitis cases) out of 457 urine samples of patients. Among toxins, haemolysin and secreted autotransporter toxin are found more frequently in isolates causing pyelonephritis (p < 0.020) than cystitis (p < 0.083). The frequent occurrence of P-pili, S-fimbria and protein involved in intestinal colonisation was noted among E. coli isolates associated with pyelonephritis. Overall, the study suggests that clinical isolates associated with pyelonephritis are more virulent than those associated with cystitis and diversified association with various antimicrobial resistance phenotypes was noted.  相似文献   
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