全文获取类型
收费全文 | 75303篇 |
免费 | 5032篇 |
国内免费 | 2815篇 |
专业分类
耳鼻咽喉 | 874篇 |
儿科学 | 973篇 |
妇产科学 | 319篇 |
基础医学 | 4796篇 |
口腔科学 | 678篇 |
临床医学 | 8650篇 |
内科学 | 14967篇 |
皮肤病学 | 917篇 |
神经病学 | 2426篇 |
特种医学 | 1623篇 |
外国民族医学 | 41篇 |
外科学 | 8108篇 |
综合类 | 14538篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 4215篇 |
眼科学 | 528篇 |
药学 | 7635篇 |
80篇 | |
中国医学 | 5855篇 |
肿瘤学 | 5924篇 |
出版年
2024年 | 197篇 |
2023年 | 1271篇 |
2022年 | 2488篇 |
2021年 | 3200篇 |
2020年 | 2759篇 |
2019年 | 2395篇 |
2018年 | 2247篇 |
2017年 | 2503篇 |
2016年 | 2897篇 |
2015年 | 2877篇 |
2014年 | 5831篇 |
2013年 | 5756篇 |
2012年 | 5116篇 |
2011年 | 5441篇 |
2010年 | 4246篇 |
2009年 | 3697篇 |
2008年 | 3506篇 |
2007年 | 3633篇 |
2006年 | 3041篇 |
2005年 | 2698篇 |
2004年 | 2098篇 |
2003年 | 1769篇 |
2002年 | 1464篇 |
2001年 | 1498篇 |
2000年 | 1296篇 |
1999年 | 1108篇 |
1998年 | 938篇 |
1997年 | 778篇 |
1996年 | 759篇 |
1995年 | 727篇 |
1994年 | 678篇 |
1993年 | 506篇 |
1992年 | 454篇 |
1991年 | 419篇 |
1990年 | 413篇 |
1989年 | 349篇 |
1988年 | 335篇 |
1987年 | 252篇 |
1986年 | 182篇 |
1985年 | 190篇 |
1984年 | 201篇 |
1983年 | 127篇 |
1982年 | 134篇 |
1981年 | 100篇 |
1980年 | 127篇 |
1979年 | 95篇 |
1978年 | 72篇 |
1977年 | 76篇 |
1976年 | 64篇 |
1975年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
S. Kitano H. Kawanaka M. Tomikawa H. Hirabayashi M. Hashizume K. Sugimachi 《Surgical endoscopy》1994,8(5):405-407
In a 48-year-old Japanese man there was an uncontrollable and recurrent bleeding from a gastric ulcer and laparoscopic surgery was done. Two cannulae were placed in the gastric cavity through the abdominal wall and suture ligation of the bleeding vessel at the posterior wall of the stomach was done under videovisual control with endoscopic guidance. The bleeding ceased, complications were nil, and he remains well.This article reports on surgery done to repair uncontrollable, recurrent bleeding from a gastric ulcer. Two cannulae were placed in the gastric cavity through the abdominal wall and suture of the vessel at the posterior wall of the stomach was done with videovisual control and endoscopic guidance. This approach is concluded to have supplied minimal-access surgery, cost effectiveness, early discharge, less pain, and doctor-patient satisfaction. 相似文献
43.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc. 相似文献
44.
W. Schwizer R. Fraser H. Maecke K. Siebold R. Funck M. Fried 《Magnetic resonance in medicine》1994,31(4):388-393
Current MR meal markers may interfere with gastric motility and secretion restricting the use of MRI in the measurement of gastric physiology. We therefore evaluated Gd-DOTA as a liquid phase marker, in vitro by determining dissociation, and adherence to the solids, and in vivo by simultaneous MRI (0.35 T scanner, multiple T1-weighted sections of the upper abdomen) and double indicator (perfusion marker PEG 4000, meal marker 99mTc-DTPA) measurements of emptying and secretion, following ingestion of 500 ml 10% glucose. In vitro Gd-DOTA was stable at a pH > 2 with < 2% dissociation at 24 h during incubation with HCI. Dissociation during incubation with HCI was linearly dependent on H+ concentration (0.77 < pH < 2.02). Less Gd-DOTA was absorbed onto the solid phase than 99mTc-DTPA (25% cf 36%). in vivo Gd-DOTA marked gastric contents provided strong positive contrast. Similar emptying curves were observed with both MRI and double-indicator techniques (r = 0.987, P < 0.001). Gd-DOTA has the potential to be a useful liquid phase contrast agent in MR studies on gastric function. 相似文献
45.
60例(男50,女10,年龄43±8a)经内窥镜证实的活动性消化性溃疡患者,口服法莫替丁40mg,qn,疗程2-4wk或延至6-9wk。溃疡愈合率DU2,4,6 wk分别为50%,84%,92%,SU2,4,6,8 wk分别为40%,68%,73%,82%。服药后3,7,14 d上腹痛缓解率DU为50%,80%,100%,SU为40%,75%,95%。未见严重不良反应。故法莫替丁对溃疡病,尤其是DU是一有效和安全药物。 相似文献
46.
K. Groeneveld A. H. M. M. Balk A. J. Ouwehand E. H. M. Loonen M. vd Linden S. Strikwerda B. Mochtar N. H. P. M. June W. Weimar 《Transplant international》1992,5(Z1):S228-S230
Chronic rejection (CR) is a major problem in long-term survival in heart transplantation. We analysed whether the occurrence of CR correlates with the incidence of acute rejections (AR) or with characteristics of endomyocardial biopsy-derived cell cultures. CR was diagnosed by annual angiography and defined as all coronary vascular changes. One year after transplantation 24 of the 63 patients had CR (38%). The incidence of AR in CR + and CR — patients was comparable. The patients in both groups had similar individual median percentages of EMB-yielding cell cultures. During the first year the CR — patients had more cultures in which at least 60% of the cells were CD4 + T cells (50% vs 37%, P = 0.05), due to a stronger CD4 predominance in the first 6 months. In the second year the CD4 predominance in the patients diagnosed as CR + after 1 year tended to be higher (P = 0.08). The patients had comparable percentages of cultures predominated by CD8 + T cells, γδ T cells or NK cells, irrespective of the time interval. These results might indicate that CD4 + T lymphocytes play a dual role in the aetiology of CR. 相似文献
47.
J. F. Bergmann O. Chassany P. J. Guillausseau M. Bayle S. Chagnon C. Caulin J. R. Sallenave 《European journal of clinical pharmacology》1992,43(2):121-124
Summary The aim of the study was to use a novel combination of two methods for the simultaneous evaluation of two effects of oral cisapride in 10 diabetic patients with autonomic neuropathy; gastric emptying time was measured by following radio-opaque markers and orocaecal transit time by the sulphasalazine-sulphapridine method. The study was of double-blind, randomized, placebo-controlled, cross-over design.It was possible to evaluate the effect of a prokinetic drug on gastric emptying and orocaecal transit times using these two noninvasive techniques at the same time. Cisapride significantly reduced both the gastric emptying (1.2 h versus 2.1 h) and orocaecal tansit (5.9 h versus 7.7 h) times. 相似文献
48.
S. van Ruth† EBL van Dorst‡ MR Canninga-van Dijk§ MS de Bruin-Weller† 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):678-680
Cutaneous metastasis of vaginal carcinoma is extremely rare. So far, the total number of reported skin metastasis of vaginal carcinoma is only one. We present another case with an unusual manifestation of vagina carcinoma metastasis: skin metastasis presenting as a leg ulcer on the lower leg. 相似文献
49.
目的用缺氧方法制备的肺源性心脏病(肺心病)大鼠为对象,研究肺心病中M2和β1受体抗体的含量及其与疾病的关系。方法选取健康雄性Wistar大鼠36只,随机分为3组:单纯缺氧组,缺氧加注射FeCl3组,健康对照组。SA-酶联免疫吸附测定(ELISA)法检测血清M2和β1受体抗体变化。最后处死大鼠观察心脏指标,并分析它与抗体滴度的相关性。结果血清中M2和β1受体抗体随缺氧时间延长而升高,滴度分别到第3周达高峰M2受体抗体为1∶80(单纯缺氧组)和1∶53(缺氧加注射FeCl3组),β1受体抗体为1∶60(单纯缺氧组)和1∶45(缺氧加注射FeCl3组),并且P/N值从第2周开始有阳性意义,到第3周同样达高峰M2和β1受体抗体分别为2.88(单纯缺氧组)、2.76(缺氧加注射FeCl3组)和3.25(单纯缺氧组)、3.99(缺氧加注射FeCl3组)。而肺心病大鼠心脏指标最终改变为R/(L+S)0.333±0.027(单纯缺氧组),0.348±0.033(缺氧加注射FeCl3组),R/BW×10-30.58±0.13(单纯缺氧组),0.60±0.15(缺氧加注射FeCl3组),(L+S)/BW×10-32.000±0.024(单纯缺氧组),2.081±0.037(缺氧加注射FeCl3组),并且抗体滴度与心脏改变呈正相关。结论M2和β1受体抗体阳性率及抗体滴度在大鼠肺心病模型中明显增高,表明肺心病的发生发展与M2和β1受体的自身抗体密切相关。 相似文献
50.