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71.
72.

Background  

Muleba district in North-western Tanzania has experienced malaria epidemics in recent years. Community knowledge, attitudes and practices are important in enhancing disease control interventions. This study investigated determinants of malaria epidemics in the study area in relation to household knowledge, attitudes and practice on malaria.  相似文献   
73.
In the environment, nonylphenol (NP) occurs predominantly as a degradation product of nonylphenol ethoxylate (NPE). They can be found in many types of products including detergents, plastics, emulsifiers, pesticides, and industrial and consumer cleaning products. As a consequence of their use in a variety of products, they are quite common in rivers and other aquatic environments that receive sewage discharges. Because of its enhanced resistance towards biodegradation, toxicity, estrogenic effects, and ability to bioaccumulate in aquatic organisms NP has been regarded as the most critical metabolite of APEs. We have studied the in vivo and in vitro metabolism and organ distribution of NP in juvenile salmon. Fish were exposed in vivo to waterborne [3H]-4-n-NP for a period up to 72 h or were administered a single oral dose of [3H]-4-n-NP. In vitro biotransformation of NP was studied by exposure of cultured salmon hepatocytes to [3H]-4-n-NP in the presence or absence of a CYP1A-inducer, beta-naphthoflavone (betaNF). Our results show that 4-n-NP was mainly metabolized in vivo, to its corresponding glucuronide conjugates and hydroxylates. The major route of excretion was the bile. The half-life of residues in carcass and muscle was between 24 and 48 h in both waterborne and dietary exposure. In whole body autoradiography, intragastric administered [3H]-4-n-NP was mainly present in the gastrointestinal tract and bile. NP-derived radioactivity in fish exposed via water was more evenly distributed in the organs compared to intragastric exposure and were observed in the intestinal contents, liver, kidney, gills, skin, abdominal fat and brain. In vitro pretreatment of hepatocytes with betaNF had no effect on rates or patterns of NP biotransformation. The in vitro metabolic rate of NP were 118 pmol NP metabolized/h/0.5x10(6) cells without betaNF, and 98 pmol NP metabolized/h/0.5x10(6) cells when betaNF was added to the culture medium.  相似文献   
74.
OBJECTIVE: To evaluate the efficacy and safety of interferon-alpha2a (IFN-alpha2a) in relapsing-remitting MS (RRMS). BACKGROUND: Several immune-modulating therapy regimens of IFN-alpha have shown varying results in MS. A recent pilot study suggested benefits from IFN-alpha2a. METHODS: Ninety-seven patients were randomized to receive subcutaneous injections of placebo (33 patients) or 4.5 million international units (mIU) (32 patients) or 9.0 mIU (32 patients) of IFN-alpha2a three times weekly for 6 months, with a further 6 months of follow-up. Monthly gadodiamide-enhanced MRI was the primary method of evaluating efficacy. RESULTS: IFN-alpha2a treatment resulted in fewer new MRI lesions during the treatment period (p < 0.003). The probability of no new lesions during treatment was >2.5 times higher with 9.0 mIU IFN-alpha2a than with placebo (p < 0.005). The median number of lesions at the end of treatment was lower with IFN-alpha2a treatment than with placebo (p = 0.0004), but the difference disappeared during follow-up. The total number of lesions (mean) increased by 4.78 with placebo, 0.86 with 4.5 mIU IFN-alpha2a, and 0.28 with 9.0 mIU IFN-alpha2a during treatment (p = 0.030). No treatment effect on exacerbation rate, progression of disability, or quality of life was detected. Nine patients discontinued treatment, five because of adverse events. CONCLUSIONS: IFN-alpha2a treatment significantly reduced disease activity as measured by MRI, but the efficacy disappeared within 6 months after discontinuation of treatment. A long-term study of more patients using disability as a primary outcome measure is needed to evaluate the clinical impact.  相似文献   
75.
76.

Background  

Health research is increasingly being conducted on a global scale, particularly in the developing world to address leading causes of morbidity and mortality. While research interest has increased, building scientific capacity in the developing world has not kept pace. This often leads to the export of human tissue (defined broadly) from the developing to the developed world for analysis. These practices raise a number of important ethical issues that require attention.  相似文献   
77.
This paper describes the first pregnancy in a childless widow after intracytoplasmic sperm injection (ICSI) treatment with her deceased husband's spermatozoa which had been stored for nearly 3 years before use. Before his death the husband had received treatment for testicular cancer and he had given the appropriate written consent for the future use of his spermatozoa. Of the 10 eggs injected, six resulted in normal embryos. Three embryos were transferred and the remaining three embryos are currently stored for possible future use. The treatment resulted in a continuing singleton pregnancy. The case demonstrated the suitability of ICSI in those difficult cases where the sperm quality is extremely poor. This success is also compared with a widely debated case of another widow who was refused permission to use her deceased husband's spermatozoa. It is concluded that in the case of posthumous use of frozen spermatozoa, the current laws are conveniently applicable in a chronic illness but not so in an acute illness leading to death. In the light of the wide public debate on the issues raised by this legal case, the UK Government has also decided to conduct a review of consent procedures involving the storage and use of genetic material.   相似文献   
78.
79.

Background  

Tuberculosis is a major cause of morbidity and mortality globally. Recent scholarly attention to public health ethics provides an opportunity to analyze several ethical issues raised by the global tuberculosis pandemic.  相似文献   
80.
Siess  W; Boehlig  B; Weber  PC; Lapetina  EG 《Blood》1985,65(5):1141-1148
We have studied the effects of two stable prostaglandin endoperoxide analogues on platelet lipid metabolism in relation to specific platelet functional changes. During platelet shape change, the endoperoxide analogues induce the formation of 1,2-diacylglycerol and phosphatidic acid, indicating the activation of a phosphoinositide-specific phospholipase C. In parallel, they stimulate the phosphorylation of a 40-kd and a 20-kd protein. During platelet shape change, arachidonic acid is released, but not metabolized by platelet cyclo-oxygenase or lipoxygenase. Phospholipase C activation and platelet shape change are independent of extracellular Ca++ and Mg++, arachidonate metabolism, and release of adenosine diphosphate (ADP). Activation of phospholipase C during platelet aggregation seems, however, to be mediated partly by release of ADP. We conclude that endoperoxide analogues initially stimulate in platelets the formation of products derived from phospholipase C activation, which might serve as intracellular messengers for phosphorylation of specific proteins related to platelet shape change.  相似文献   
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