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991.
Tae-Min Rhee Kyung Woo Park Chi-Hoon Kim Jeehoon Kang Jung-Kyu Han Han-Mo Yang Hyun-Jae Kang Bon-Kwon Koo Hyo-Soo Kim 《JACC: Cardiovascular Interventions》2018,11(24):2453-2463
Objectives
The aim of this study was to investigate clinical outcomes after left main coronary artery (LM) bifurcation percutaneous coronary intervention (PCI) and the impact of the duration of dual antiplatelet therapy (DAPT) according to treatment strategy.Background
There are limited data regarding the optimal PCI strategy for LM bifurcation lesions with new-generation drug-eluting stents.Methods
A patient-level pooled analysis of 5 nationwide multicenter registries was performed. Rates of target lesion failure, thrombotic adverse cardiovascular events, and their individual components at 3-year were analyzed. Subgroup analysis according to DAPT duration was performed.Results
From 13,172 patients undergoing PCI with new-generation drug-eluting stents, a total of 700 patients were treated for LM bifurcation lesions, 567 with a 1-stent strategy and 133 with a 2-stent strategy. Rates of target lesion failure and target lesion revascularization were higher in the 2-stent group, driven mainly by complex lesion profiles. Risks for thrombotic adverse cardiovascular events and its components were comparable between the 2 strategies. Subgroup analysis showed that risks for target lesion failure and thrombotic adverse cardiovascular events in the 2-stent group were significantly higher than in the 1-stent group in those with DAPT interruption <1 year, while they were similar in those receiving DAPT maintenance ≥1 year.Conclusions
Up to 20% of patients who underwent LM bifurcation PCI eventually required a 2-stent strategy, which was as safe as a 1-stent strategy with the use of new-generation drug-eluting stents. Careful pre-emptive case selection as well as prolonged DAPT may be necessary when considering a 2-stent strategy in LM PCI given its higher rate of repeat revascularization and lesion failure than the 1-stent approach. 相似文献992.
993.
Influence of graft size matching on outcomes of infantile living donor liver transplantation 下载免费PDF全文
Ping Wan Qigen Li Jianjun Zhang Conghuan Shen Yi Luo Qimin Chen Xiaosong Chen Ming Zhang Longzhi Han Qiang Xia 《Pediatric transplantation》2015,19(8):880-887
We aimed to assess the impact of size mismatching between grafts and recipients on outcomes of infants or small children after LDLT. Between October 2006 and December 2014, 129 LDLT recipients weighing no more than 8 kg were retrospectively analyzed. The entire cohort was categorized into three groups by GRWR: GRWR<3.0% (group A, n = 38), 3.0%≤GRWR<4.0% (group B, n = 61), and GRWR≥4.0% (group C, n = 30). Baseline characteristics were similar among groups A, B, and C. Compared with groups A and B, post‐transplant alanine aminotransferase and aspartate aminotransferase within seven days were significantly higher in group C; however, differences between total bilirubin and albumin after transplantation were not prominent. Moreover, incidences of surgical complications, perioperative deaths, infections, and acute rejections were all comparable among the three groups. Five‐yr patient survival rates for groups A, B, and C were 89.5%, 88.9%, and 81.6%, respectively (p = 0.872), and the graft survival rates were 89.5%, 86.6%, and 81.6%, respectively (p = 0.846). In conclusion, GRWR between 1.9% and 5.8% would not cause noticeable adverse events for infantile LDLT recipients ≤8 kg. However, there is still a role for considering reduction in the graft mass as an applicable strategy in selected cases. 相似文献
994.
Fraxiparin, a low-molecular-weight heparin, stimulates megakaryocytopoiesis in vitro and in vivo in mice 总被引:1,自引:0,他引:1
Z. X. Shen N. Basara X. D. Xi J. Caen J. P. Maffrand M. Pascal M. Petitou J. C. Lormeau Z. C. Han 《British journal of haematology》1994,88(3):608-612
Summary. The effect of a low-molecular-weight heparin, faxiparin (Nadroparinŕ;), on murine megakaryocytopoiesis in vitro and in vivo was studied in comparison with unfractionated heparin. The addition of fraxiparin at 1–20 IU/ml into plasma clot cultures but not serum-free agar culture significantly enhanced MK colony growth. Furthermore, fraxiparin was found to potentiate the stimulating activity of aplastic anaemia serum (AAS) but not stem cell factor (SCF), interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (Epo), on MK colony growth in vitro , and to neutralize the inhibitory effect of platelet factor 4 (PF4) in vitro and in vivo . Fraxiparin also acted synergistically with heparin confactor II and antithrombin III to promote megakaryocyte colony formation. Intraperitoneal administration of fraxiparin twice daily for 4d at 0.1–25IU/injection increased in mice the level of blood platelet counts and the number of single MKs and CFU-MK in bone marrow. These data demonstrate that fraxiparin is able to positively regulate megakaryocytopoiesis. 相似文献
995.
Parturition in sheep is initiated by the fetus through activation of the fetal hypothalamic-pituitary-adrenal axis and is associated with increased concentrations of ACTH, cortisol, and corticosteroid-binding globulin (CBG) in the fetal circulation during the final 10-15 days of pregnancy. Premature parturition and a precocious elevation in fetal plasma CBG are produced by intrafetal ACTH administration, but the possible sources of CBG in the ovine fetus are not known. To determine these sites, CBG mRNA was measured in tissues from fetal sheep in late pregnancy and after intrafetal ACTH treatment, using a sheep CBG cDNA. Fetal ACTH treatment caused a significant increase in the fetal plasma corticosteroid-binding capacity (CBC), although there was no significant difference in CBC between umbilical arterial and umbilical venous plasma. After ACTH treatment, CBC was elevated in fetal liver and kidney. Cortisol binding in these tissues had characteristics similar to those of cortisol binding in fetal sheep plasma. By Northern blot analysis a single mRNA (1.7 kilobases) for CBG was detected in fetal liver, kidney, lung, and adrenal, but not in placenta. The abundance of CBG mRNA in the fetal liver was greater than that in other tissues, but was unchanged by ACTH treatment. The level of CBG mRNA in the fetal kidney, but not in other tissues, increased 3-fold after ACTH. We conclude that the elevation in plasma CBC after intrafetal ACTH, and presumably also at term pregnancy, does not reflect production of CBC by the placenta or transfer from the mother. Rather, it results from production primarily in the fetal liver and kidney, although only in the latter tissue is CBG mRNA accumulation increased by intrafetal ACTH treatment. 相似文献
996.
May Han Michel Groesbeek Thomas P. Sakmar Steven O. Smith 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(25):13442-13447
The visual pigment rhodopsin is a prototypical G protein-coupled receptor. These receptors have seven transmembrane helices and are activated by specific receptor–ligand interactions. Rhodopsin is unusual in that its retinal prosthetic group serves as an antagonist in the dark in the 11-cis conformation but is rapidly converted to an agonist on photochemical cis to trans isomerization. Receptor–ligand interactions in rhodopsin were studied in the light and dark by regenerating site-directed opsin mutants with synthetic retinal analogues. A progressive decrease in light-dependent transducin activity was observed when a mutant opsin with a replacement of Gly121 was regenerated with 11-cis-retinal analogues bearing progressively larger R groups (methyl, ethyl, propyl) at the C9 position of the polyene chain. A progressive decrease in light activity was also observed as a function of increasing size of the residue at position 121 for both the 11-cis-9-ethyl- and the 11-cis-9-propylretinal pigments. In contrast, a striking increase of receptor activity in the dark—i.e., without chromophore isomerization—was observed when the molecular volume at either position 121 of opsin or C9 of retinal was increased. The ability of bulky replacements at either position to hinder ligand incorporation and to activate rhodopsin in the dark suggests a direct interaction between these two sites. A molecular model of the retinal-binding site of rhodopsin is proposed that illustrates the specific interaction between Gly121 and the C9 methyl group of 11-cis-retinal. Steric interactions in this region of rhodopsin are consistent with the proposal that movement of transmembrane helices 3 and 6 is concomitant with receptor activation. 相似文献
997.
Glaucoma and ocular hypertension are highly prevalent conditions in individuals over the age of 40 and are commonly seen together in patients with cardiovascular disease. Many of the antiglaucoma medications, when systemically absorbed, affect the sympathetic and parasympathetic nervous systems of patients and can cause cardiovascular toxicity. Such adverse effects are frequently associated with the long-term use of potentially toxic agents in elderly people, who are most prone to chronic eye disease. Moreover, patients may not associate their symptoms with the topical eye medications, and consequently may not report adverse drug effects. Drug-drug interactions can also occur when patients are taking medications for both cardiovascular disease and glaucoma. In this review, the systemic toxicity of these agents is reviewed, along with possible drug-drug interactions. Mention is made of other antiglaucoma medications used alone and in combination with topical beta-blockers. Identification of genetic loci-a bold new step toward glaucoma treatment-is mentioned briefly at the end of the article. 相似文献
998.
Factor concentrates have been shown to have a variety of immunomodulatory effects in vitro. The presence of plasma-derived factor VIII (pdFVIII) has been shown to diminish lymphocyte proliferative response to mitogens. Recently, we have shown the presence of transforming growth factor-beta (TGF-beta) as an immunomodulatory component present in plasma-derived FVIII concentrate. However, the addition of neutralizing antibody to TGF-beta did not abrogate the inhibitory effect of pdFVIII on monocyte cytokine production, suggesting the presence of other, as yet undetermined, immunomodulatory agent/s in pdFVIII. To further characterize the immunomodulatory effects of pdFVIII, the in vitro effect of pdFVIII concentrate on proliferation and apoptosis of mitogen-stimulated T cells was studied using whole blood and purified T cells. The presence of pdFVIII increased the apoptosis of phytohaemagglutinn (PHA) -stimulated CD4 and CD8 T-cell subsets as determined by Annexin V binding and DNA fragmentation. T-cell subsets showed a pdFVIII dose-dependent inhibition of entry into S-phase and G(1) arrest. Addition of neutralizing anti-TGF-beta reduced some of these changes. To determine the physiological relevance of these findings, blood samples from five patients receiving FVIII prophylaxis were similarly studied ex vivo and showed significantly increased apoptosis of T-cell subsets as determined by Annexin V staining. TGF-beta has been reported to be a potent inhibitor of T-cell proliferation, arresting the cell cycle in G(1) phase and causing apoptosis. Together, these findings suggest that TGF-beta is a significant immunomodulatory component of pdFVIII concentrates. 相似文献
999.
Effects of fenofibrate on high-fat diet-induced body weight gain and adiposity in female C57BL/6J mice 总被引:3,自引:0,他引:3
Jeong S Han M Lee H Kim M Kim J Nicol CJ Kim BH Choi JH Nam KH Oh GT Yoon M 《Metabolism: clinical and experimental》2004,53(10):1284-1289
Our previous study suggested that fenofibrate affects obesity and lipid metabolism in a sexually dimorphic manner in part through the differential activation of hepatic peroxisome proliferator-activated receptor alpha (PPARalpha) in male and female C57BL/6J mice. To determine whether fenofibrate reduces body weight gain and adiposity in female sham-operated (Sham) and ovariectomized (OVX) C57BL/6J mice, the effects of fenofibrate on not only body weight, white adipose tissue (WAT) mass, and food intake, but also the expression of both leptin and PPARalpha target genes were measured. Compared to their respective low-fat diet-fed controls, both Sham and OVX mice exhibited increases in body weight and WAT mass when fed a high-fat diet. Fenofibrate treatment decreased body weight gain and WAT mass in OVX, but not in Sham mice. Furthermore, fenofibrate increased the mRNA levels of PPARalpha target genes encoding peroxisomal enzymes involved in fatty acid beta-oxidation, and reduced apolipoprotein C-III (apo C-III) mRNA, all of which were expressed at higher levels in OVX compared to Sham mice. However, leptin mRNA levels were found to positively correlate with WAT mass, and food intake was not changed in either OVX or Sham mice following fenofibrate treatment. These results suggest that fenofibrate differentially regulates body weight and adiposity due in part to differences in PPARalpha activation, but not to differences in leptin production, between female OVX and Sham mice. 相似文献
1000.
Mehmet?DoganEmail authorView authors OrcID profile Tolga?Han?Efe Tolga?Cimen Cem?Ozisler Mehmet?Ali?Felekoglu Ahmet?Goktug?Ertem Mehmet?Erat Omer?Yiginer Murat?Tulmac 《Lung》2018,196(2):173-178