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111.
Adult zebrafish can completely regenerate their caudal fin following amputation. This complex process is initiated by the formation of an epithelial wound cap over the amputation site by 12 h post amputation (hpa). Once the cap is formed, mesenchymal cells proliferate and migrate from sites distal to the wound plane and accumulate under the epithelial cap forming the blastemal structure within 48 hpa. Blastemal cells proliferate and differentiate, replacing the amputated tissues, which are populated with angiogenic vessels and innervating nerves during the regenerative outgrowth phase which is completed around 14 days post amputation (dpa). Regenerative outgrowth does not occur in TCDD-exposed zebrafish. To identify the molecular pathways that are perturbed by TCDD exposure, male zebrafish were ip injected with 50 ng/g TCDD or vehicle and caudal fins were amputated. Regenerating fin tissue was collected at 1, 3, and 5 dpa for mRNA abundance analysis. Microarray analysis and quantitative real time PCR revealed that wound healing and regeneration alone altered the expression of nearly 900 genes by at least two-fold between 1 and 5 dpa. TCDD altered the abundance of 370 genes at least two-fold. Among these, several known aryl hydrocarbon responsive genes were identified in addition to several genes involved in extracellular matrix composition and metabolism. The profile of misexpressed genes is suggestive of impaired cellular differentiation and extracellular matrix composition potentially regulated by Sox9b. 相似文献
112.
作者采用肌蒂移植术治疗胸腰段陈旧性脊髓损伤56例.脊髓功能恢复率提高至Franke 1个等级以上者占76.8%(43/56).本文讨论了肌蒂移植术对陈旧性脊髓损伤的适应证.安徽省宿州市骨伤科医院淮北煤矿基建局医院 相似文献
113.
玻璃纤维增强复合树脂在总义齿基托中的应用 总被引:1,自引:0,他引:1
目的:增强总义齿基托的机械性能,提高总义齿的基托抗折裂能力。方法:对E-玻璃纤维用KH-550处理剂进行表面处理后,加入总义齿基托中,制成玻璃纤维增强复合树脂。结果:经过1年的临床观察后复诊,没有发现裂纹。结论:玻璃纤维增强得合树脂可以有效地增强总义齿基托的机械性能。 相似文献
114.
弥可保对断指再植后感觉恢复的疗效评价 总被引:1,自引:0,他引:1
目的探讨弥可保(甲基维生素B12)对周围神经损伤患者的感觉神经再生作用并对比不同剂量弥可保的神经再生作用。方法将62例81指近节断指再植术后的病例,根据急诊病历号随机分为3组:A组:弥可保1500μg肌肉注射,每日1次,共30次后改为500μg口服,每日3次,共4个月。B组:弥可保500μg肌肉注射,每日1次,共30次后改为500μg口服,每日3次,共4个月。C组:阴性对照组。术后随访4~6个月,平均随访5.6个月。定期测定再植手指指腹的30g压觉,2g触觉,5g痛觉以及两点分辨觉。结果3组对照,实验组手指感觉功能恢复均明显优于阴性对照组,1500μg弥可保组感觉功能恢复显著优于500μg弥可保组。结论弥可保对周围神经损伤后的恢复有促进作用,且与药物的剂量呈正相关。 相似文献
115.
细胞移植治疗心肌梗死的研究与展望 总被引:2,自引:0,他引:2
细胞移植是治疗心肌梗死的一种新策略,本文对目前应用于临床研究的骨骼肌卫星细胞移植及骨髓干细胞移植治疗心肌梗死的进展进行综述。上述两种细胞移植均具有来源丰富、无排斥反应的特点,而且通过研究观察表明,上述两种细胞移植后,心脏功能均能得到改善,故具有美好发展前景。但二者亦均具有不足之处和需要解决的问题,还需进一步研究与探索。 相似文献
116.
①目的 比较不同方式吻合神经的再生情况。②方法 将 72只Wistar大白鼠随机分为 3组 ,每组 2 4只。分别以端端吻合、部分端端吻合、端侧吻合方式吻合颈 7近端与颈 6远端 ,观测手术后 4、8、12、16周各组再生纤维轴突数目及有髓轴突截面积。③结果 术后 4、12、16周部分端端吻合组再生轴突数目及截面积与端端吻合组比较 ,差异无显著性 (F =3.75、3.18,P >0 .0 5 ) ;端侧吻合组术后 4、8、12、16周再生轴突数目及截面积均低于端端吻合组及部分端端吻合组 ,差异有显著性 (F =8.2 3~ 4 5 .71,q=5 .2 5~ 16 .4 8,P <0 .0 5 )。④结论 神经部分端端吻合具有一定的临床应用价值 相似文献
117.
Knut A. Selvig Ulf M. E. Wikesjö Gary C. Bogle Richard D. Finkelman 《Journal of clinical periodontology》1994,21(6):380-385
Abstract. Effects of a topically applied growth factor combination on fibroblast migration, collagen fiber formation and bone regeneration were studied in standardized periodontal defects in 4 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and into the dentin of maxillary and mandibular teeth. Collagen sponges, impregnated with 200 ng insulin-like growth factor II, 20 ng basic fibroblast growth factor and 6 ng transforming growth factor beta 1 were fitted to defects randomly in right or left quadrants and the flaps repositioned and sutured. Contralateral control defects received the collagen with vehicle only. Experimental procedures were staggered to allow observations of healing 3, 7, 10, and 14 days after surgery. Histometric analysis showed no differences in fibroblast and collagen density between control and growth factor defects. Bone regeneration was significantly greater in control than in growth factor defects 10 and 14 days after surgery. The rate of healing generally appeared more affected by intra-dog variations or procedural variations than by the growth factor combination. 相似文献
118.
应用自体颅骨碎片及骨屑对60例在造成颅骨缺损术同时行颅骨缺损修补术。缺损面积直径最小者2cm,最大者10cm。术后随访1个月至5年,病人颅骨缺损修补处外观正常,无凹陷,触之硬,与正常颅骨处类似。6个月拍X线片示颅骨修补处类似正常颅骨形态。 相似文献
119.
本文采用形态测量技术,分析了雌激素对大鼠肝再生过程中肝细胞超微结构的影响。结果显示,使用雌激素的大鼠肝细胞核及核仁体积明显高于对照组,以术后1~3d最明显(P<0.001);同时,线粒体数密度也明显增加,术后1、3、7d与对照组比较差异有极显著性意义(P<0.01),表明雌激素具有促进肝再生过程中肝细胞线粒体增生的作用。作者认为,雌激素的上述作用是雌激索促进肝细胞再生的形态学表现。 相似文献
120.
Role of progenitor endothelial cells in cardiovascular disease and upcoming therapies. 总被引:2,自引:0,他引:2
Atsuhiko Kawamoto Takayuki Asahara 《Catheterization and cardiovascular interventions》2007,70(4):477-484
The field of cell-based transplantation has expanded considerably and is poised to become an established cardiovascular therapy in the near future. In this review, we will focus on endothelial progenitor cells (EPCs), which are immature cells capable of differentiating into mature endothelial cells. EPCs share many surface marker antigens such as CD34, AC133, Flk-1, etc. with hematopoietic stem cells (HSCs) and the major source of EPCs as well as HSCs is the bone marrow (BM). BM-derived EPCs are mobilized into peripheral blood and recruited to the foci of pathophysiological neovascularization and reendothelialization, thereby contributing to vascular regeneration. Severe EPC dysfunction is an indicator of poor prognosis and severe endothelial dysfunction. Indeed, number of circulating EPCs and their migratory activity are reduced in patients with diabetes, coronary artery disease (CAD), or subjects with multiple coronary risk factors. Effective neovascularization induced by EPC transplantation for hindlimb, myocardial, and cerebral ischemia has been demonstrated in many preclinical studies, and early clinical trials of EPC transplantation in chronic and acute CAD indicate safety and feasibility of myocardial cell-based therapies. For therapeutic reendothelialization in patients undergoing percutaneous coronary intervention, CD34 antibody-coated stents have been used clinically to capture circulating EPCs at the injury sites and enhance reendothelialization and safety of stents. Further development in cell processing technology for efficient isolation, expansion, mobilization, recruitment, and transplantation of EPCs into target tissues are underway and expected to be tested in clinical trials in the near future. 相似文献