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91.
92.
Surgery occupies only a restricted position in post-phlebitic illness. The authors analyse 157 surgical operations carried out on 138 patients between 1969 and 1983. A detailed report is always given pre-operatively as a matter of course by Functional examination and phlebography, in order to locate the predominant physiopathological disorder or disorders: superficial venous deficiency--reflux via the perforators--the obliteration syndrome or devalvulation syndrome of the deep venous system. After a short listing of the surgical methods, the results of these different operations are analysed. They are hard to assess. Where there is a relapsing ulcer, surgery of the perforators produces 70 percent good results. The therapeutic indications are discussed, finally, on the basis of recently published series and the authors' experience.  相似文献   
93.
In HIV-1-infected patients with long-term undetectable viraemia on highly active antiretroviral treatment (HAART), we found that pre-HAART plasma viraemia and the baseline proviral DNA level were significantly associated with the viraemia setpoint during scheduled treatment interruptions. In long-term treated patients, pre-HAART viraemia may not be available, and in these circumstances proviral DNA, measured at the time of scheduled treatment interruption, can help to identify patients likely to reach a low viraemia setpoint after treatment interruption.  相似文献   
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Summary We report here a case of primary hepatic anaplastic large cell Ki‐1 non‐Hodgkin's lymphoma in a 60 year old patient followed for hereditary hemochromatosis.  相似文献   
97.
M H Perrin  Y Haas  J Porter  J Rivier  W Vale 《Endocrinology》1989,124(2):798-804
Binding of the GnRH agonist [DAla6,NMe-Leu7,Pro9Net]GnRH to bovine anterior pituitary membranes is inhibited by guanyl nucleotides. The effect of guanyl nucleotides is temperature dependent, in that significant binding inhibition is observed when the receptor-hormone interaction is measured at 37 C, and no inhibition is seen at 4 C. Micromolar concentrations of the nonhydrolyzable GTP analog 5'-guanylylimidodiphosphate [Gpp(NH)p] displace the bound agonist in a dose-dependent manner, with half-maximal displacement occurring in a concentration range of 0.1-0.5 microM, and maximum displacement occurring at a concentration of 50 microM Gpp(NH)p. At a concentration of 50 microM, the other nucleotides GTP and GDP inhibit binding to a lesser extent, while GMP, cGMP, 5'-adenylylimidodiphosphate [App(NH)p], ATP, and cAMP have no effect on the binding. At 37 C, Gpp(NH)p reduces the affinity of the agonist by a factor of 6 and increases its dissociation rate. In the presence of Gpp(NH)p at 37 C, there is also a 2-fold increase in the total number of binding sites. Under the same conditions as those used for the agonist, there is no displacement of the bound antagonist [Ac-D2Nal1,4ClDPhe2,D3Pal3,DLys6,Lys8,D Ala10]-GnRH by doses up to 50 microM Gpp(NH)p. The modulation of the binding of the agonist, but not that of the antagonist, by guanyl nucleotides is characteristic of receptors that are coupled to GTP-binding proteins. Thus, the GnRH receptor appears to be coupled to a GTP-binding protein that may play a role in the mechanism of action of GnRH at the pituitary.  相似文献   
98.
Peptides of the corticotropin-releasing factor (CRF) family signal through the activation of two receptors, CRF receptor type 1 (CRFR1) and type 2 (CRFR2), both of which exist as multiple splice variants. We have identified a cDNA from mouse brain encoding a splice variant, soluble CRFR2alpha (sCRFR2alpha), in which exon 6 is deleted from the gene encoding CRFR2alpha. Translation of this isoform produces a predicted 143-aa soluble protein. The translated protein includes a majority of the first extracellular domain of the CRFR2alpha followed by a unique 38-aa hydrophilic C terminus resulting from a frame shift produced by deletion of exon 6. By using RT-PCR and Southern hybridization, the relative mRNA expression levels of full-length (seven transmembrane domains) CRFR2alpha and the soluble form (sCRFR2alpha) in the mouse brain were measured with a single reaction. The results demonstrate high levels of expression of sCRFR2alpha in the olfactory bulb, cortex, and midbrain regions. A rabbit antiserum raised against a synthetic peptide fragment encoding the unique C terminus revealed specific sCRFR2alpha immunoreactivity in mouse brain slices by immunohistochemistry and in extracts of brain regions by RIA. Interestingly, the sCRFR2alpha immunoreactivity distribution closely approximated that of CRFR1 expression in rodent brain. A protein corresponding to sCRFR2alpha, expressed and purified from either mammalian or bacterial cell systems, binds several CRF family ligands with low nanomolar affinities. Furthermore, the purified sCRFR2alpha protein inhibits cellular responses to CRF and urocortin 1. These data support a potential role of the sCRFR2alpha protein as a possible biological modulator of CRF family ligands.  相似文献   
99.
This clinical study analysed the changes in right ventricular ejection fraction induced by changes in right ventricular afterload using a new thermodilution catheter linked to a rapid response computer which allowed instantaneous measurements of the right ventricular ejection fraction. The first group comprised 16 patients referred for coronary angioplasty with single vessel disease (isolated proximal stenosis of one of the two main branches of the left coronary artery) and a normal left ventricular ejection fraction (> or = 55%) and mean pulmonary artery pressure of < 25 mmHg: right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after 60 seconds' coronary occlusion with the balloon catheter in order to assess the effects of the reactional increase in afterload on the right ventricular ejection fraction. The second group comprised 11 patients with dilated primary cardiomyopathy with decreased left ventricular ejection fraction (< 50%) and mean pulmonary artery pressure > or = 25 mmHg: the right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after intravenous trinitrin (performed to evaluate the pulmonary reaction to vasodilators) in order to analyse the effects of the reduction of afterload on right ventricular ejection fraction. Negative linear correlations were observed between the right ventricular ejection fraction and mean pulmonary artery pressure under basal conditions (r = -0.72; p < 0.005) and between the right ventricular ejection fraction and mean pulmonary artery pressure after changing the conditions of afterload (r = -0.82; p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
The aim of this study was to test the effectiveness of isosorbide-5-mononitrate (IM) as an adjunct to propranolol (PR) in the prevention of variceal rebleeding. Ninety-five cirrhotic patients with variceal bleeding were randomly assigned to treatment with PR + IM (46 patients) or PR alone (49 patients). Eighteen patients in the PR + IM group and 28 in the PR group had rebleeding during the 2 years after randomization. The actuarial probability of rebleeding 2 years after randomization was lower in the PR + IM group (40.4% vs. 57.4%) but the difference was not significant (P =. 09). However, the decrease in the risk of rebleeding reached statistical significance after stratification according to age, i.e. less than 50 versus >/=50 years old, (P =.03) or by adding an additional year of follow-up (P =.05). No significant difference was found in rebleeding index and survival. The multivariate Cox analysis indicated first, that both treatment (P =.03) and age (P =. 001) were factors predictive of rebleeding and second, that PR + MI reduced the risk of rebleeding by half (relative risk: 0.51, 95% confidence interval: 0.28-0.95). Seven patients in the PR + MI group and 1 patient in the PR group had to discontinue one of the drugs because of adverse events (P =.03). These results suggest that the addition of IM improves the efficacy of PR alone in the prevention of variceal rebleeding in cirrhotic patients. However no beneficial effects were observed on other parameters reflecting the efficacy of treatment.  相似文献   
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