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目的观察多发伤患者早期全血中CD3^+(CD3阳性淋巴细胞)、CD4^+(CD4阳性淋巴细胞)、CD8^+(CD8阳性淋巴细胞)的动态变化并探讨多发伤与免疫的关系。方法观察2005年-2007年我院多发伤患者人院1wk内CD3^+、CD4^+.CD8^+浓度的变化。结果24h内CD3^+、CD4^+.CD4^+/CD8^+比值明显降低,48h之后CD4^+值降低不明显,而CD8^+降低,CD4^+/CD8^+比值恢复。结论严重多发伤后患者免疫功能受到明显抑制,在72h之前达到高峰,此后缓慢地回升。  相似文献   
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Inhibition of chemotaxis Ng-monomethyl-L-arginine: a role for cyclic GMP   总被引:8,自引:0,他引:8  
The metabolism of L-arginine to nitric oxide (NO) has been shown to be important for the effector functions of many cell types, including polymorphonuclear (PMN) leukocytes. Its effect appears to be mediated at least in part by NO stimulation of soluble guanylate cyclase. We evaluated the role of this pathway in two PMN effector functions: cell movement and microbial killing, using the competitive inhibitor of L- arginine conversion to NO, NG-monomethyl-L-arginine (NMA). We also evaluated the effect of additional L-arginine and dibutyryl cyclic guanosine monophosphate (cGMP) on any NMA-associated changes. Human peripheral blood neutrophils were used and the cells were incubated with and without NMA. Chemotaxis was evaluated using a 48-well micro- Boyden chamber. Microbial killing was evaluated using S aureus strains D2C and 502A. These studies demonstrated that chemotaxis to formyl- methionyl-leucyl-phenylalanine was markedly inhibited in NMA-treated cells. This inhibition could be overcome if L-arginine or dibutyryl cGMP were added with the NMA. In contrast, microbial killing of S aureus was unaffected by NMA. These observations support the hypothesis that the L-arginine metabolism to NO and its effect on the cGMP level may be important for the dynamic changes required for neutrophil chemotaxis.  相似文献   
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The biologic effects of the oil shale industry on caged rainbow trout (Oncorhynchus mykiss) as well as on feral perch (Perca fluviatilis) and roach (Rutilus rutilus) were studied in the River Narva in northeast Estonia. The River Narva passes the oil shale mining and processing area and thus receives elevated amounts of polycyclic aromatic hydrocarbons (PAHs), heavy metals, and sulfates. The effects of the chemical load were monitored by measuring cytochrome P4501A (CYP1A)-dependent monooxygenase (MO) activities [7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase (AHH)] as well as conjugation enzyme activities [glutathione S-transferase (GST) and UDP-glucuronosyltransferase] in the liver of fish. CYP1A induction was further studied by detecting the amount and occurrence of the CYP1A protein. Histopathology of tissues (liver, kidney, spleen, and intestine) and the percentage of micronuclei in fish erythrocytes were also determined. Selected PAHs and heavy metals (Cd, Cu, Hg, and Pb) were measured from fish muscle and liver. In spite of the significant accumulation of PAHs, there was no induction of MO activities in any studied fish species. When compared to reference samples, AHH activities were even decreased in feral fish at some of the exposed sites. Detection of CYP1A protein content and the distribution of the CYP1A enzyme by immunohistochemistry also did not show extensive CYP1A induction. Instead, GST activities were significantly increased at exposed sites. Detection of histopathology did not reveal major changes in the morphology of tissues. The micronucleus test also did not show any evidence of genotoxicity. Thus, from the parameters studied, GST activity was most affected. The lack of catalytic CYP1A induction in spite of the heavy loading of PAHs was not studied but has been attributed to the elevated content of other compounds such as heavy metals, some of which can act as inhibitors for MOs. Another possible explanation of this lack of induction is that through adaptation processes the fish could have lost some of their sensitivity to PAHs. Either complex pollution caused by oil shale processing masked part of the harmful effects measured in this study, or oil shale industry did not have any severe effects on fish in the River Narva. Our study illustrates the difficulties in estimating risk in cases where there are numerous various contaminants affecting the biota.  相似文献   
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BACKGROUND: Between 1987 and 1992, the Finnish Institute of Occupational Health (FIOH) initiated and implemented the Asbestos Program that aimed at reducing asbestos-related risks. It was a cooperative effort between government authorities, labor market organizations, and health care and labor protection personnel. METHODS: During the Program and its follow-up since 1993 several preventive actions were taken, and considerable new legislation and official instructions were issued. RESULTS: Approximately 200,000 people in Finland have been exposed to asbestos in their work. Through the cooperative efforts of government, labor, health care and worker protection programs, the import of asbestos was ceased in 1993 with a few exceptions. Almost all imports ceased in 2005 following European Union directives. Regulation of asbestos abatement companies has been greatly increased. The occupational exposure limit has been reduced from 2.0 fibers/cm(3) to the present 0.1 fibers/cm(3). Asbestos-related diseases are closely monitored and education of health care providers regarding the occupational source of these conditions is now emphasized. CONCLUSIONS: The success of the primary goal of the Program, a reduction in asbestos-related morbidity, will not be fully realized for many decades.  相似文献   
57.
The aim of the study was to investigate the effects of regular aerobic exercise training on bone mineral density (BMD) in middle-aged men. A population based sample of 140 men (53–62 years) was randomly assigned into the exercise and reference groups. BMD and apparent volumetric BMD (BMDvol) of the proximal femur and lumbar spine (dual-energy X-ray absorptiometry, DXA) and anthropomorphic measurements were performed at the randomization and 2 and up to 4 years later. The participation rate was 97% and 94% at the second and third BMD measurements, respectively. As another indication of excellent adherence and compliance, the cardiorespiratory fitness (aerobic threshold) increased by 13% in the exercise group. The 2% decrease in the reference group is regarded as an age-related change in cardiorespiratory fitness. Regardless of the group, there was no association between the increase in aerobic threshold and change in BMD. In the entire group, age-related bone loss was seen in the femoral neck BMD and BMDvol (p<0.01). BMD and BMDvol values increased with age in L2–L4 (p<0.004). An increased rate of bone loss at the femoral neck was observed in men with a low energy-adjusted calcium intake (p = 0.003). Men who increased their alcohol intake during the intervention showed a decrease in the rate of bone loss at the femoral neck (p = 0.040). A decrease in body height associated with decreased total femoral BMD (r= 0.19, p = 0.04) and the change in body height was a predictor of bone loss in the femoral neck (β= 0.201). Long-term regular aerobic physical activity in middle-aged men had no effect on the age-related loss of femoral BMD. On the other hand, possible structural alterations, which are also essential for the mechanical strength of bone, can not be detected by the DXA measurements used in this study. The increase seen in lumbar BMD reflects age-related changes in the spine, thus making it an unreliable site for BMD follow-up in men. Received: August 2000 / Accepted: November 2000  相似文献   
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In 1987–1992, the Finnish Institute of Occupational Health (FIOH) implemented a nationwide asbestos program aimed at preventing asbestos-related risks in good cooperation with governmental authorities, industry, trade unions, the health care and insurance systems, and mass media. The goals were to minimize all exposure to asbestos, identify people exposed at work, and improve the diagnostics of asbestos diseases, especially cancers. The program entailed several concrete actions and extensive dissemination of information, training, services, and scientific research. As proposed by the State Asbestos Committee, new use of asbestos products was banned and strict regulations were applied to renovation and inspection of old buildings. The screening study of asbestos-induced diseases included 18,943 current and retired workers from house building, shipyard, and asbestos industries. Pleural and parenchymal changes were found in 4.133 persons (22%), who were referred to further clinical examinations as suspected cases of an occupational disease. It was estimated that past exposure of asbestos among the Finnish population of 5 million causes > 150 mesotheliomas and lung cancers annually, totalling > 2,000 asbestos-induced cancer deaths by the year 2010. Although several major control actions were made or started during the program, the bulk of the preventive work still lies ahead.  相似文献   
60.
A total of 57 subjects who had been exposed to mould dust in the tobacco industry were studied. Their working environment showed exposure to spores of different moulds, and 29 subjects (51%) showed antibodies against one or more of the microbes. Fifteen (26%) had work related respiratory symptoms. Eight (14%) showed slight radiographic pulmonary fibrosis. Spirometry showed a tendency toward restriction and obstruction, especially in small airways. Diffusion capacity was decreased in 18% of the workers. Three clinical cases of typical allergic alveolitis were also found. All this suggests that exposure of spores of different moulds (especially Aspergillus fumigatus) in the manufacture of tobacco products may induce symptoms and signs relating to extrinsic allergic alveolitis.  相似文献   
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