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21.
观测了急性肝炎和重症肝炎病人血浆VitE及Lpo水平及其动态变化。急性肝炎和重症肝炎病人血浆VitE低于对照组,Lpo高于对照组,均以重症肝炎更明显,且死亡病例血浆VitE低于存活者。部份病人口服VitE不能提高其血浆水平,并随病情加重而逐渐降低。讨论了病毒性肝炎病人血浆VitE降低与Lpo升高的关系及其临床意义,认为动态观测血浆VitE可作为判断重症肝炎病情进展及预后的参考。  相似文献   
22.
BACKGROUND: Food allergy to cherry occurs throughout Europe, typically with restricted oral reactions in the central and northern parts but with frequent systemic reactions in the Mediterranean region. Previous studies have demonstrated insufficient sensitivity of commercially available cherry extract reagents in the diagnosis of cherry allergy. OBJECTIVE: To assess the diagnostic performance of specific IgE tests based on recombinant cherry allergens in comparison with an extract-based assay and to skin prick test (SPT). A secondary objective was to analyse the frequency of systemic reactions in cherry-allergic subjects across Europe, including the largest population of LTP-sensitized subjects from central Europe studied to date. METHODS: A total of 186 subjects from central Europe and Spain were studied. Serum IgE was analysed with ImmunoCAP tests carrying rPru av 1, 3 and 4, combined and separately, and cherry extract. RESULTS: Among the central European cherry allergics, the mix of rPru av 1, 3 and 4 had a sensitivity of 95%, compared with 65% for cherry extract, and the IgE binding capacity of the recombinant mix was considerably higher. The sensitivity of the two tests was more comparable in the Spanish population, 95% and 86%, respectively. The recombinant allergen ImmunoCAP equalled SPT in terms of sensitivity and specificity. Consistent with previous reports, major geographic differences in sensitization pattern and prevalence of systemic reactions were found. A significantly higher rate of systemic reactions was found in Spanish patients sensitized to Pru av 3 whereas German patients sensitized to LTP only had oral allergy syndrome. CONCLUSIONS: The recombinant cherry allergen ImmunoCAP is a highly sensitive diagnostic tool, clearly superior to any diagnostic method based on cherry extract. Three cherry allergens are sufficient for detecting sensitization in 95% of cherry-allergic subjects. Systemic reactions are common in LTP-sensitized individuals but seem to require at least one additional causative factor.  相似文献   
23.
猕猴桃中药复方制剂对血清SOD及MDA含量的影响   总被引:4,自引:0,他引:4  
猕猴桃中药复方制剂系采用猕猴桃汁为基质,配加绞股蓝、丹参等中药的有效成分制成。为了研究它的保健作用,在63例50岁以上、无急性疾病的中、老年人,36例30~49岁健康的青年,32例14~17岁健康的少年中进行试验,10ml每日2次连续服用30天后,中老年人血液SOD显著增高,70岁以上老人平均增高2.8倍,血清MDA明显下降,70岁以上平均下降87.5%。  相似文献   
24.
人血浆纤维结合素对家兔刮除和板层切除后的角膜上皮愈合均有一定促进作用,角膜上皮裸区明显缩小,优于对照眼。临床治疗5类角膜上皮障碍59例61眼,均获得显著疗效。  相似文献   
25.
BACKGROUND: The plasma kallikrein-kinin system (PKKS) has been implicated in cardiovascular disease, but activation of the PKKS has not been directly probed in individuals at risk of coronary heart disease (CHD) or stroke. OBJECTIVE: To determine the involvement of the PKKS, including factor XI, in cardiovascular disease occurring in a nested case-control study from the Second Northwick Park Heart Study (NPHS-II). METHODS AND RESULTS: After a median follow-up of 10.7 years, 287 cases of CHD and stroke had been recorded and 542 age-matched controls were selected. When FXIIa-C1 esterase inhibitor (C1-inhibitor) concentrations were divided into tertiles (lowest tertile as reference), the odds ratios (ORs) at 95% CIs for CHD were 0.52 (0.34-0.80) in the middle tertile and 0.73 (0.49-1.09) in the highest tertile (P = 0.01 for the overall difference; P = 0.01 for CHD and stroke combined). For kallikrein-C1-inhibitor complexes, the ORs for stroke were 0.29 (0.12-0.72) and 0.67 (0.30-1.52) in the middle and high tertiles, respectively (P = 0.02). FXIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes were negatively related to smoking and fibrinogen (P < 0.005). FXIa-inhibitor complexes correlated strongly with FXIIa-inhibitor complexes. CONCLUSIONS: Lower levels of inhibitory complexes of the PKKS enzymes and particularly of FXIIa contribute to the risk of CHD and stroke in middle-aged men. This observation supports the involvement of the PKKS in atherothrombosis.  相似文献   
26.
Rituximab, intravenous immunoglobulin (IVIG) and rabbit antithymocyte globulin (rATG) all have been suggested to have an effect on antibody producing cells, however, supporting data are lacking. To assess the impact of these agents on splenic B‐cell populations in vivo, we retrospectively examined 25 spleens removed from patients treated with these agents as part of desensitization protocols in either ABO incompatible or positive crossmatch living donor kidney transplantation. These were compared to control (CTL) spleens removed for trauma. CTLs and spleens removed at transplant after multiple pretransplant plasmaphereses (PP) plus low‐dose IVIG showed similar large numbers of naïve B cells (CD20+ and CD79+), plasma cells (CD138+) and memory B cells (CD27+ cells). Adding rituximab to this PP/IVIG regimen reduced the number naïve B cells, but had no effect on memory or plasma cells. Combination treatment (PP/IVIG, rituximab and rATG) showed a trend toward the reduction of CD27+ cells, but again plasma cells were unchanged. We conclude that none of these protocols reduces splenic plasma cells in vivo. PP/low‐dose IVIG does not alter splenic B cells, but the addition of rituximab decreases mature B cells. Memory B cells may be affected by combination therapy including rATG and requires further study.  相似文献   
27.
Iron overload and liver fibrosis   总被引:1,自引:0,他引:1  
  相似文献   
28.
Permeability of pure lipid bilayers to melatonin   总被引:9,自引:1,他引:8  
Abstract: Melatonin, the chief hormone of the pineal gland, has been reported to interact with a variety of different cells. This ubiquitously acting hormone has been found to interact with protein receptors both at the cell membrane and in the nucleus. Moreover, melatonin was recently shown to be a very potent hydroxyl radical scavenger. The present work focuses on the interaction of melatonin with pure lipid bilayers. It is shown that melatonin can cross multilamellar lipid vesicles, which are used here as model systems for the lipid phase of biological membranes. Thus, the data prove that melatonin can easily pass through the cell membrane and bath every part of the cell, as previously suggested in the literature. Melatonin lipid association constant was calculated based on the change of the hormone fluorescence intensity due to its penetration into the hydrophobic lipid phase. Though melatonin was recently shown to be highly soluble in aqueous media, its lipid association constant is rather high, indicating that the biological action of the hormone is likely to be at the membrane level, either via its interaction with membrane receptors, and/or as a lipoperoxidation radical scavenger.  相似文献   
29.
Recent studies suggest that abnormalities occur at the lipid level in malignant hyperthermia susceptible humans and pigs. To test this hypothesis, we first investigated the physical state of plasma membranes of lymphocytes isolated from normal and malignant hyperthermia susceptible swine. In halothane-challenged pigs, malignant hyperthermia susceptibility was also assessed by ryanodine binding assay on purified sarcoplasmic reticulum membranes. The results clearly show that plasma membrane of lymphocytes from malignant hyperthermic pigs are significantly more fluid than controls. We then attempted to apply the same methodology to lymphocytes prepared from human patients previously diagnosed by the halothane and caffeine contracture test. In that case, there was no clear relationship between malignant hyperthermia susceptibility and the fluidity state of lymphocyte plasma membranes.  相似文献   
30.
Six patients with prolonged acute courses of thrombotic microangiopathy are reviewed. These patients had in common courses of acute disease requiring plasma support for more than 3 months, with subsequent complete remission. Plasma support requirements may be prodigious, and the acute course may require more than 100 plasma exchanges before a stable remission is achieved. These patients appear to represent a subset of thrombotic microangiopathy distinct from the more common acute T.T.P. course, which resolves in 3–6 weeks, and the chronic relapsing pattern, which may have a short or prolonged acute course. © 1992 Wiley-Liss, Inc.  相似文献   
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