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861.
We assessed the clinical usefulness of theintraductal secretin test in order to ascertain whetherit can substitute for the conventional duodenal secretintest. Duodenal juice was obtained with a triple-lumen tube and pure pancreatic juice was obtained byretrograde cannulation of the main pancreatic duct usinga duodenofiberscope. Pancreatic secretion was stimulatedby a bolus intravenous injection of secretin (100 units). The two tests showed comparableinterindividual coefficients of variation, significantlygood correlations, and comparable diagnosticefficiencies. The intraductal secretin test showed noless reproducibility than that of the duodenalsecretin test as reported in the literature. In theintraductal secretin test, secretory volume, peak flowrate, bicarbonate output, and lipase output yielded the best diagnostic efficiency, followed by amylaseoutput and maximal bicarbonate concentration. In theintraductal secretin test, a 10-min collection providedas much information as a 20-min collection. We conclude, therefore, that the 10-minintraductal secretin test is as useful as theconventional duodenal secretin test in assessingexocrine pancreatic function and that the mostdiscriminatory parameters are secretory volume, bicarbonate output, andamylase (or lipase) output.  相似文献   
862.
Adherence of diarrhea-associated Escherichia coli was studied by scanning electron microscopy. Enteropathogenic E. coli (EPEC) adherence factor-positive (EAF+) E. coli of EPEC serotypes (class I EPEC) adhered to plastic and human jejunal and ileal mucosa, similar to case and HeLa cells. Localized adherence, elongation of cell microvilli, and "locking" of the bacterial aggregates by the elongated microvilli were evident after incubation for 20 min. EAF+ E. coli adhered strikingly to mucus but rarely to M cells in Peyer's patch-associated epithelium. Most enteroaggregative E. coli (EAggEC) strains adhered to plastic, similar to HeLa cells. Some diffuse-adhering E. coli (DAEC) strains displayed no adherence to plastic but formed "dimples" on HeLa cells. Both EAggEC and DAEC adhered at lower levels to human small intestines (except M cells) than did EAF+ E. coli. In all cases of EAF+ E. coli, EAggEC, and DAEC, strains were found with atypical characteristics. The data demonstrate the unique adherence characteristics of EAF+ E. coli, EAggEC, and DAEC.  相似文献   
863.
Angiogenesis involves endothelial cell invasion and migration into the surrounding tissue where cells differentiate, to form new lumen-containing vessels. We have investigated the role of phosphoinositide 3-kinase (PI3-kinase) in vascular endothelial growth factor (VEGF)- and fibroblast growth factor (FGF)-induced angiogenesis. Angiogenesis in vivo in chick embryos was inhibited by treatment with the PI3-kinase inhibitors wortmannin and LY294002. Stimulation of primary bovine capillary endothelial (BCE) cells with FGF-2, VEGF-A165, or a combination of the two induced PI3-kinase activity in vitro and subsequent activation of the serine/threonine kinase Akt. The combination of FGF-2 and VEGF-A165 led to an additive response. Activation of PI3-kinase was strictly required for FGF-2- and VEGF-A165-induced migration and DNA synthesis of BCE cells. Tubular morphogenesis was unaffected by treatment with wortmannin or LY294002, but survival of the tubular structures was dependent on PI3-kinase activity. VEGF-A165 and FGF-2 induced increased stability of the tubular structures in a synergistic manner. These data indicate that PI3-kinase activity is required for migration, mitogenicity and survival but not for differentiation of endothelial cells during angiogenesis. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
864.
865.
866.
BackgroundEndothelial progenitor cells (EPCs) derived from bone marrow migrate to areas of endothelial damage and repair them. EPC function is impaired by oxidative stress. We examined the effects of an antioxidative beta(1)-adrenoceptor blocker on the number and function of EPCs in hypertensive rats.MethodsSpontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats were fed diets loaded with high salt. The SHRs were treated with celiprolol or atenolol for 2 weeks. Peripheral blood mononuclear cells (MNCs) were separated, subjected to flow cytometric analysis to determine the number of circulating EPCs, and cultured to quantify EPC colony formation. EPC migration was evaluated in migration assay chambers. EPC senescence was evaluated using beta-galactosidase assay. Oxidative stress of EPCs was evaluated using thiobarbituric acid-reactive substance (TBARS) assay. The expression of nicotinamine adenine dinucleotide phosphate (NAD(P)H) oxidase component mRNAs in the renal cortex, aorta, and heart were evaluated by real-time PCR.ResultsThe number, colony formation, and migration of EPCs in SHRs were significantly lower than those in WKY rats. TBARS scores in EPCs from SHRs were significantly higher than those from WKY rats. Celiprolol increased the number of circulating EPCs and stimulated EPC colony formation and migration, while decreasing EPC senescence. Celiprolol inhibited oxidation in EPCs from SHRs, and decreased the expression of NAD(P)H oxidase component mRNAs in the renal cortex, aorta, and heart.ConclusionEPCs are impaired in SHRs in response to oxidative stress. Celiprolol decreases oxidative stress in hypertension in vivo and improves EPC numbers and function. It appears, therefore, that celiprolol may exert beneficial cardiovascular effects through its antioxidative properties.American Journal of Hypertension (2008). doi 10.1038/ajh.2008.233American Journal of Hypertension (2008); 21, 9, 1062-1068. doi 10.1038/ajh.2008.233.  相似文献   
867.
AIMS: We have recently reported that serum deoxyribonuclease I (DNase I) activity, which may be involved in apoptosis, increases abruptly in the early phase of acute myocardial infarction (MI) [Kawai Y, Yoshida M, Arakawa K, Kumamoto T, Morikawa N, Masamura K, Tada H, Ito S, Hoshizaki H, Oshima S, Taniguchi K, Terasawa H, Miyamori I, Kishi K, Yasuda T. Diagnostic use of serum deoxyribonuclease I activity as a novel early-phase marker in acute myocardial infarction. Circulation 2004;109:2398-2400]. Death of vascular smooth muscle cells, in part because of apoptosis, is postulated to heighten susceptibility to disruption of vulnerable plaque, resulting in onset of MI. The present study evaluated the possibility that Gln222Arg polymorphism of the DNase I gene may be one of the factors involved in predisposition to MI. METHODS AND RESULTS: We assessed 611 Japanese patients: 311 with MI and 300 with stable angina pectoris (AP). Three common phenotypes determined by two common codominant alleles, DNASE1*1 and *2, whose corresponding gene products exhibit different properties, were found in these patient groups. The prevalence of DNASE1*2 was significantly higher in patients with MI than in those with AP (0.543 vs. 0.428, P < 0.001), being confirmed by phenotyping of the second study population. Multiple logistic regression analysis showed that the odds ratio of DNASE1*2 was 1.51 [95% confidence interval (CI) 1.04-2.18]. The association of the DNASE1*2 allele with MI was statistically significant, being independent of other conventional risk factors. CONCLUSION: Our data demonstrate that Gln222Arg polymorphism in the DNase I gene is associated with MI in the Japanese patients.  相似文献   
868.
A 74-year-old woman was treated with steroid and cyclosporine A for hypersensitivity pneumonia. To examine the causes of general fatigue and increased levels of beta-D glucan in serum, she was admitted to our hospital. Chest computed tomography (CT) scan revealed nodular opacity with a well-defined margin in the right S1. 67Ga scintigraphy image showed high uptake in the left thigh and CT showed circularly enhanced lesions in the thigh. An ultrasonography-guided needle aspiration and biopsy of the muscle abscess allowed isolation of Aspergillus fumigatus and evidence of necrotic tissues around the granuloma formation. We therefore diagnosed invasive aspergillosis. Because of the poor response to initial therapy with micafungin and itraconazole for 4 weeks, we treated her with voliconazole (VCZ). Spectacular regression of lung lesions and muscle abscesses was rapidly achieved. Furthermore, the high level of beta-D glucan in serum decreased gradually. This case suggests that administration of VCZ can be recommended for deep seated mycoses.  相似文献   
869.
870.
Matrix metalloproteinase 9 (MMP-9) degrades type IV collagen, gelatin, type V collagen and type XI collagen. We measured proMMP-9 and proMMP-9-TIMP-1 complex in sera and joint fluids by sandwich ELISA, and immunohistochemically examined the expression of this enzyme in joint tissues from patients with rheumatoid arthritis (RA). ProMMP-9 was purified from the culture medium of HT 1080 cells by the three steps of chromatography. Purified proMMP-9 and activated MMP-9 by aminophenylmercuric acetate showed two bands of 92 and 67 kDa on gelatin zymography. We raised two monoclonal antibody clones, named 2G9 and 8G7, against proMMP-9. 2G9 and 8G7 reacted with proMMP-9 in western blotting and these clones reacted not only with proMMP-9, but also with proMMP-9-TIMP-1 complex in sandwich ELISA, respectively. The proMMP-9 concentration in 86 sera (749.4±940.2 ng/ml) and 54 joint fluids (4539.9±7681.5 ng/ml) from patients with RA was significantly higher than those of patients with osteoarthritis (15 sera: 139.0±149.6 ng/ml; 16 joint fluids: 655.0±1982.8 ng/ml) and control (37 sera: 266.7±120.4 ng/ml; three joint fluids: 0 ng/ml). The immunohistochemistry with 2G9 monoclonal antibody showed that proMMP-9 were expressed in the neutrophils and the monocytes-macrophages which diffusely infiltrated in the sublining layer of rheumatoid synovium. In addition, the osteoclasts along subchondral bone were also intensively stained. The proMMP-9 concentration in joint fluids from 39 RA patients was positively correlated to the count of proMMP-9 positive cells in RA synovium (r=0.607) and to the score of diffuse infiltrates of lymphocytes (r=0.720). However, it did not show correlation to the stage and the class defined by Steinbrocker and to the other clinical laboratory data. Our results suggest that proMMP-9 actively participates in joint destruction of RA through the expression of neutrophils and monocytes-macrophages and is regulated by lymphocytes.  相似文献   
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