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101.
J. Davignon R. Dufour M. Roy C. Bétard Y. Ma S. Ouellette L. Boulet S. Lussier-Cacan 《European journal of epidemiology》1992,8(1):10-17
Of 163 individuals with a diagnosis of heterozygous familial hypercholesterolemia (FH), only one subject was found to be positive for familial defective apo B-100 (FDB). The eight-member kindred ascertained through this subject who presented with both a clinical phenotype of FH and the FDB apo B-100 (Arg3500→-Gln) mutation was studied. Plasma lipid and lipoprotein profiles, apo E phenotypes, apo B gene markers at the 3′ hypervariable region and LDL-receptor haplotypes (ApaLI, PvuII, NcoI), were determined, together with LDL-receptor activity on freshly isolated blood lymphocytes. The FDB mutation, present in four relatives, was associated with three different phenotypes: FH and severe hypercholesterolemia, moderate hypercholesterolemia and normolipidemia. The FH phenotype occurred in the absence of any functional LDL-receptor defect. In homozygotes for the absence of the PvuII cutting site who had the apo B mutation, LDL-cholesterol levels were low in the presence of the apo E3/2 phenotype and high in the presence of the apo E4/4 phenotype. None of the major known environmental influences accounted for the wide range of variation in LDL-cholesterol among the affected members. Further observations in the spouse and offspring of the normolipidemic FDB subject confirmed the association of apo E4, the FDB mutation and the PvuH(-/-) genotype with high cholesterol levels. It is concluded that the phenotypic expression of the FDB mutation may vary widely as a function of the genetic environment within a family. The presence of phenotypic heterogeneity among individuals with the same apo B mutation may result from epistatic interaction of the apo B locus with genetic factors regulating cholesterol homeostasis, including possible involvement of the apo E and the LDL-receptor gene loci. This study also confirms that the clinical diagnosis of FH is not necessarily associated with an LDL-receptor defect. 相似文献
102.
报告应用微粒皮肤移植技术抢救成功7例特大面积烧伤病人。文中介绍了手术方法、注意事项,指出了本术式的优缺点,并对该领域国内外的发展状况,作了简单叙述。 相似文献
103.
Activated neutrophils aggravate endothelial dysfunction after reperfusion of the ischemic feline myocardium. 总被引:3,自引:0,他引:3
Endothelial dysfunction, as evidenced by decreased stimulated release of endothelium-derived relaxing factor (EDRF), occurs after reperfusion of the ischemic myocardium. To better understand this endothelial dysfunction, isolated cat hearts were perfused under constant flow by the Langendorff procedure with Krebs-Henseleit solution devoid of blood cells. Following global ischemia (90 minutes) and reperfusion (20 minutes), coronary vasorelaxation to the endothelium-dependent vasodilator acetylcholine (ACh) was 70 +/- 3% of initial values (p less than 0.01) compared with 90 +/- 4% in nonischemic control perfused hearts. No decrement occurred in response to the endothelium-independent vasodilator nitroglycerin (NTG). Coronary artery rings isolated from the ischemic left circumflex coronary artery showed a similar degree of endothelial dysfunction to ACh, with normal relaxation in response to NaNO2. Autologous cat neutrophils (100 million cells), activated with 100 nmol/L f-met-leu-phe infused into the heart directly before and throughout reperfusion, resulted in a further decrement in ACh-induced vasodilation, to 55 +/- 5% of initial response, with no effect on NTG-induced vasodilation. Similar results were obtained with coronary artery rings isolated from perfused cat hearts and exposed to neutrophils. This neutrophil-enhanced endothelial dysfunction was inhibited by human superoxide dismutase as well as by an antibody to the adherence glycoprotein complex CD-18 (i.e., MAbR 15.7). Therefore endothelial dysfunction occurs initially upon reperfusion of the previously ischemic heart and is aggravated by superoxide radicals produced by activated neutrophils. 相似文献
104.
105.
实验研究了小剂量γ线照射及合并噪声暴露对脉鼠外周血NK细胞活性的影响。结果表明,单纯γ线照射和单纯噪声暴露组动物外周血NK细胞活性较对照组部有一定程度的增高,其中尤以后者为明显。但噪声暴露对γ线照射引起的NK细胞活性无明显影响;而γ线照射对噪声暴露引起的NK细胞活性却表现有一定的拮抗作用,其机理有待探讨。 相似文献
106.
Adultacuteleukemia (AL)isoneofthemostcommonmalignanttumorsofhematology .Withtherecentprogressinchemotherapyandsupportivether apy ,theremissionandsurvivalrateinALhavebeenmarkedlyimproved .However ,drugresistanceandrelapsearestillimportantfactorsaffectinglongsur vivalofthese patients .Theabnormalregulationofcellcycleisanotherfactorthatcannotbeignoredex ceptformultipledrugresistance (MDR) .WedetectcyclinA ,multidrugresistantgene (mdrl) ,topoiso meraseⅡα(TopⅡα)andbcl 2inadultpatientswithA… 相似文献
107.
报道30例腕部损伤患者,伤情比较相同。其中12例采用传统外科手术治疗,不作或仅作不正规的理疗;18例采用显微外科技术治疗,仔细修复各种组织结构,术后系统地进行康复治疗。经随访3个月~2年,传统方法治疗组优良率仅为8.3%;采用显微外科技术及康复治疗组优良率达67%。 相似文献
108.
1992年12月作者从一位EHF患者的早产儿脐带血中分离出EHFV,证实EHFV沿母、婴垂直途径传播的可能性。 相似文献
109.
辽宁产东亚钳蝎毒镇痛作用与脑内中枢关系的研究 总被引:3,自引:0,他引:3
应用立体定位、核团内注射与电解损毁核团技术及微电极细胞外记录方法,以猫丘脑后核内脏大神经诱发单位放电为内脏痛指标,观察向尾状核、中脑导水管周围灰质及杏仁内侧核内注入东亚钳蝎毒及在电解损毁3个核团前后PO内脏大神经诱发单位放电的变化。在损毁诸核之前刺激内脏大神经引起单位诱发放电,损毁诸核之后诱发放电减弱或消失,这与辽宁产东亚钳蝎毒注入诸核团中的作用相一致。表明蝎毒的作用部位与上述核团有关,更进一步证明蝎毒作用部位 相似文献
110.
广东汉族人群HLA-Cw多态性及单体型分析 总被引:1,自引:0,他引:1
目的检测广东汉族人群HLA.Cw及HLA-A、B、DRB1基因频率,分析该人群HLA-Cw等位基因多态性及其单体型特点。方法骨髓移植供者185例,抗凝血提取DNA,半量全自动PCR-RSSO分型检测HLA-A、B、Cw、DRB1基因型。结果在分辨水平检出Cw等位基因11个,其中分布频率较高的依次为:Cw*03(0.2580)、Cw*07(0.1887)、Cw*01(0.1732)、Cw*08(0.1070)。统计分析呈现显著连锁不平衡的HLA-Cw.A单体型7个,HLA-Cw-B单体型20个,HLA—Cw.DRB1单体型10个。结论广东汉族群体HLA-Cw基因具有较为丰富的多态性,其与HLA-A、B、DRB1间连锁不平衡单体型具有地区性遗传特征。 相似文献