全文获取类型
收费全文 | 7246篇 |
免费 | 261篇 |
国内免费 | 254篇 |
专业分类
耳鼻咽喉 | 140篇 |
儿科学 | 114篇 |
妇产科学 | 64篇 |
基础医学 | 706篇 |
口腔科学 | 280篇 |
临床医学 | 511篇 |
内科学 | 1020篇 |
皮肤病学 | 55篇 |
神经病学 | 508篇 |
特种医学 | 249篇 |
外科学 | 1062篇 |
综合类 | 1123篇 |
现状与发展 | 1篇 |
预防医学 | 399篇 |
眼科学 | 46篇 |
药学 | 949篇 |
中国医学 | 375篇 |
肿瘤学 | 159篇 |
出版年
2023年 | 56篇 |
2022年 | 96篇 |
2021年 | 128篇 |
2020年 | 124篇 |
2019年 | 118篇 |
2018年 | 124篇 |
2017年 | 120篇 |
2016年 | 156篇 |
2015年 | 135篇 |
2014年 | 293篇 |
2013年 | 439篇 |
2012年 | 263篇 |
2011年 | 368篇 |
2010年 | 273篇 |
2009年 | 288篇 |
2008年 | 301篇 |
2007年 | 338篇 |
2006年 | 346篇 |
2005年 | 289篇 |
2004年 | 305篇 |
2003年 | 282篇 |
2002年 | 267篇 |
2001年 | 256篇 |
2000年 | 242篇 |
1999年 | 234篇 |
1998年 | 208篇 |
1997年 | 181篇 |
1996年 | 190篇 |
1995年 | 200篇 |
1994年 | 179篇 |
1993年 | 127篇 |
1992年 | 122篇 |
1991年 | 122篇 |
1990年 | 71篇 |
1989年 | 70篇 |
1988年 | 62篇 |
1987年 | 39篇 |
1986年 | 22篇 |
1985年 | 60篇 |
1984年 | 50篇 |
1983年 | 29篇 |
1982年 | 21篇 |
1981年 | 25篇 |
1980年 | 21篇 |
1979年 | 22篇 |
1978年 | 20篇 |
1977年 | 19篇 |
1976年 | 12篇 |
1974年 | 10篇 |
1973年 | 10篇 |
排序方式: 共有7761条查询结果,搜索用时 15 毫秒
61.
目的:探讨游离脂肪酸(FFAs)对体外培养的大鼠肾小球系膜细胞增殖和生长周期的影响。方法:用不同浓度的游离脂肪酸处理大鼠HBZY-1细胞株(即大鼠肾小球系膜细胞)24h~72h。采用噻唑蓝比色(MTT)法检测内皮细胞增殖情况,流式细胞术(FCM)分析法测定细胞周期变化。结果:游离脂肪酸可抑制HBZY-1细胞的生长增殖(与对照组比较,P〈0.01),且这种抑制作用具有剂量和时间依赖性;游离脂肪酸作用于HBZY-1细胞24h、48h、72h,细胞周期发生明显改变,G1期细胞数增多,S期细胞数减少(与对照组比较,P〈0.01)。结论:游离脂肪酸可通过停滞细胞生长于G1期,抑制大鼠肾小球系膜细胞的生长增殖。 相似文献
62.
目的 通过临床实践,探索一种比较简单和相对有效的治疗严重手外伤的方法,以求最大限度地恢复手功能.方法 选用部分大网膜游离移植和网膜上同时中厚植皮术修复严重手外伤伴有大面积软组织缺损.结果 1997年起应用此方法共治疗6例病人7只手,创面一期愈合.并且供区组织充足,厚薄适度,不造成供区严重损伤,随访2~8年病人没有肠粘连症状出现.结论 选用此方法修复严重手外伤术后外形不臃肿,组织柔软,并能保留部分损伤的骨关节结构,瘢痕增生不明显,有利于手内关节活动和手功能恢复. 相似文献
63.
对靶向寡肽溶栓剂P6A(ARPAK)及其衍生物、RGD肽及含有自由基伪肽的靶向溶栓作用进行综述。P6A是纤溶酶原的降解产物之一,具有增加血管通透性和溶栓作用。P6A的衍生物及P6A代谢产物具有更强的溶栓作用。血栓形成中,RGD序列是纤维蛋白原与血小板结合的关键序列。将RGD序列与溶栓寡肽结合,构成了具有靶向溶栓作用的杂交寡肽。在溶栓治疗中,血流再灌注生成的大量自由基会对组织造成损伤,将自由基清除剂与溶栓寡肽结合可得到具有溶栓和自由基清除双向功能的溶栓伪肽。因为溶栓处是产生大量自由基的部位,所以含自由基清除剂的溶栓伪肽可将自由基清除剂带到自由基堆积部位,体现了靶向内涵。 相似文献
64.
用氟离子选择电极测定牙膏中的氟含量,本法测定回收率为98.63%~104.00%,变异系数为3.83%。 相似文献
65.
G. Merlino M. Calcagni F. Bergamin D. Martin G. Magliacani J. Baudet 《European journal of plastic surgery》1997,20(3):145-149
Reconstruction of skin defects of the distal third of the leg and foot is often a difficult task. Shape, resistance to shearing stresses in the weight-bearing surface and sensibility are the main features that have to be restored. For coverage of this region, the authors have used, in selected patients, the lateral arm flap (LAF) since 1994. This flap is thin, easy to dissect and has the possibility to be innervated through the posterior cutaneous nerve of the arm. Fourteen cases are presented. The drawbacks of this flap are the loss of sensibility in the forearm (partially transient) and the scar on the arm, which can be rather unsightly in young ladies and when big flaps are harvested skin graft is needed. 相似文献
66.
E. Muuronen S. Asko-Seljavaara E. Tukiainen H. Härmä 《European journal of plastic surgery》1997,20(1):7-10
In massive burns, early excision and a free flap reconstruction is, in some cases, limb saving. From October 1979 to August 1993, eleven patients with massive burn injury in the upper extremity were treated using a free flap reconstruction. Eight cases were acute or subacute and three were late reconstructions. The following free flaps were used: rectus femoris microneurovascular musculocutaneous flap (2), latissimus dorsi flap (4), rectus abdominis flap (3), gluteal thigh flap (1), lateral arm flap (1), and serratus flap (1). The gluteal thigh flap was lost and it was later replaced by a rectus abdominis flap. In three cases successful reanastomosis was performed. Functional late reconstructions were performed in nine patients. In all eleven patients the limb was saved and functional recovery was satisfactory. We recommend that a free musculocutaneous or muscle flap is used, proximal to the wrist, if after careful excision of nonviable tissue, tendons, bone joint or major vessels are exposed. The rectus femoris musculocutaneous flap is a useful solution to restore extensor musculature of the forearm after extensive injury. 相似文献
67.
Saturated solubility and reaction rate constants for the decomposition of benzoyl peroxide in solution and suspension were determined for use in formulation development. The solvents studied included ethanol, propylene glycol, and cosolvent mixtures of PEG 400 and water. The solubility of benzoyl peroxide was inversely related to the solvent polarity, with greater solubility occurring with semipolar solvents. The stability of benzoyl peroxide in solution was dependent on the solvent, concentration of benzoyl peroxide, and temperature. The compound was least stable in PEG 400. Stability was improved when water was added to PEG 400. Similar solvent effects were observed in suspension. In benzoyl peroxide suspensions of PEG 400 and PEG 400/water blends, benzoyl peroxide stability was dependent on solubility, with improved stability occurring in blends where the benzoyl peroxide was least soluble. Thus, solution formulations of benzoyl peroxide in pharmaceutically acceptable solvents are unlikely to show good stability; however, suspension formulations should be reasonably stable if the vehicle is selected to provide low benzoyl peroxide solubility. 相似文献
68.
用胆红素结石(ps)兔模型进行实验,设单纯胆道梗阻(BO)组、梗阻和大肠杆茵感染(BOI)组及空白对照组,观察肝组织及胆汁氧自由基(OFR)变化情况及对PS的影响。实验结果:肝组织部分OFR、前列腺素E_2(RGE_2)及PS的动态变化趋势相似,三者呈正相关;BOI组的上述指标均较BO组为高。提示OFR可能促使PGE_2合成,后者致糖蛋白分泌而参与PS的形成;大肠杆菌感染可能在梗阻的基础上增多OFR的生成而增加了Ps的形成。 相似文献
69.
Ajit K. Shah Richard C. Brundage Kathleen D. Lake Ronald J. Sawchuk 《Biopharmaceutics & drug disposition》1995,16(1):59-70
We estimated the free fraction (fu) of cyclosporine (CyA) in the plasma from concentrations of CyA in urine (Cu) and plasma (Cp), urine flow rate (UF), and glomerular filtration rate in rabbits and in heart transplant patients. Following intravenous administration of CyA (5–30 mg kg?1) in ten NZW rabbits and oral administration of CyA (4.8–12.1 mg kg?1) in nine heart transplant patients, CyA concentrations in urine and plasma were measured by HPLC. The ratios of Cu to Cp and UF data were fitted to a physiological model of renal clearance using NONMEM. The free fraction of cyclosporine in the rabbits and the heart transplant patients was 0.0122 and 0.14, respectively. Because of the relatively low permeability of CyA across the tubular epithelium, no apparent equilibrium between Cu and Cp at any urine flow rate was reached and, therefore, the Cu to Cp ratio will not be equal to fu. 相似文献
70.
红花注射液对家兔脑缺血再灌注损伤时氧自由基变化的影响 总被引:12,自引:1,他引:11
目的:探讨红花注射液对脑缺血-再灌注损伤(CIRI)的防治效应。方法:制作健康日本大耳白兔脑缺血-再灌注损伤模型,随机平均分为红花组(n=10)、缺血-再灌注组(n=10)和假手术对照组(n=10),应用黄嘌呤氧化酶法测定血浆SOD活性,用放免法测定血浆MDA浓度,并行脑组织电镜观察。结果:脑缺血再灌注期间,血浆SOD活性明显低于假手术对照组(P<0.05);血浆MDA浓度显著高于假手术对照组,尤以再灌注120min变化更显著(P<0.01);脑组织超微结构发生异常改变。使用红花注射液后,上述指标的异常变化均明显减轻,其差异有显著性。结论:氧自由基是CIRI的重要发病学因素之一,而红花注射液可能通过清除氧自由基减轻CIRI。 相似文献