全文获取类型
收费全文 | 71246篇 |
免费 | 6129篇 |
国内免费 | 1299篇 |
专业分类
耳鼻咽喉 | 414篇 |
儿科学 | 796篇 |
妇产科学 | 720篇 |
基础医学 | 5501篇 |
口腔科学 | 1712篇 |
临床医学 | 10867篇 |
内科学 | 7353篇 |
皮肤病学 | 1108篇 |
神经病学 | 2916篇 |
特种医学 | 1461篇 |
外国民族医学 | 12篇 |
外科学 | 6323篇 |
综合类 | 10073篇 |
现状与发展 | 5篇 |
一般理论 | 15篇 |
预防医学 | 9294篇 |
眼科学 | 534篇 |
药学 | 10197篇 |
46篇 | |
中国医学 | 4393篇 |
肿瘤学 | 4934篇 |
出版年
2024年 | 206篇 |
2023年 | 1137篇 |
2022年 | 1661篇 |
2021年 | 2556篇 |
2020年 | 2370篇 |
2019年 | 4894篇 |
2018年 | 4313篇 |
2017年 | 2980篇 |
2016年 | 2224篇 |
2015年 | 2564篇 |
2014年 | 4771篇 |
2013年 | 4656篇 |
2012年 | 3830篇 |
2011年 | 4045篇 |
2010年 | 3720篇 |
2009年 | 4070篇 |
2008年 | 3165篇 |
2007年 | 3956篇 |
2006年 | 3387篇 |
2005年 | 2779篇 |
2004年 | 1677篇 |
2003年 | 1712篇 |
2002年 | 1350篇 |
2001年 | 1114篇 |
2000年 | 986篇 |
1999年 | 812篇 |
1998年 | 731篇 |
1997年 | 580篇 |
1996年 | 559篇 |
1995年 | 498篇 |
1994年 | 447篇 |
1993年 | 353篇 |
1992年 | 319篇 |
1991年 | 309篇 |
1990年 | 218篇 |
1989年 | 199篇 |
1988年 | 171篇 |
1987年 | 209篇 |
1986年 | 185篇 |
1985年 | 466篇 |
1984年 | 506篇 |
1983年 | 346篇 |
1982年 | 351篇 |
1981年 | 265篇 |
1980年 | 279篇 |
1979年 | 197篇 |
1978年 | 112篇 |
1977年 | 110篇 |
1976年 | 97篇 |
1974年 | 79篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
在微量注射大量肝脏mRNA之后,通过电压箝方法进行功能鉴定,两栖类卵母细胞成功地表达了AVPV1a受体。但在灌流AV4-8溶液时,却不能诱导卵母细胞产生内向振荡电流反应。提示AVP4-8不能通过AVPV1a受体而介导生理学效应。 相似文献
72.
目的:分析立体定向X-刀放射治疗颅内肿瘤后的近期疗效,并进行阶段性工作总结。材料和方法:53例不同类型脑瘤患者,以CT、MR、DSA图像资料作为定位依据,用德国Brain LAB治疗计划系统设计三维优化方案,西门子MD-2型直线加速器旋转照射。结果:53例患者经X-刀治疗后,近期均取得了满意效果,诸如以卡氏评分法评价,临床症状有所改善;以CT增强扫描复查观察,肿瘤大小趋于缩小或消失。结论:立体定向放射治疗后的追踪观察表明,只要严格掌握适应症,精确定位,精确计划,精心治疗,X-刀是一种安全、有效、无痛苦的治疗脑肿瘤的方法。它可起到改善临床症状,提高患者生活质量,延长生存期限的作用。 相似文献
73.
74.
An experimental model for canine visceral leishmaniasis 总被引:6,自引:1,他引:5
PEDRO ABRANCHES GABRIELA SANTOS-GOMES NURIT RACHAMIM† LENEA CAMPINO LIONEL F. SCHNUR‡ CHARLES L. JAFFE† 《Parasite immunology》1991,13(5):537-550
Seven mixed-breed dogs were challenged with either promastigotes or amastigotes of Leishmania donovani infantum strains recently isolated from naturally infected dogs. Different routes and numbers of parasites were utilized and each dog was monitored for at least 1 year post-infection. Anti-parasite specific antibody levels were measured by enzyme-linked immunosorbence, immunofluorescence, crossed-immune electrophoresis and Western blotting on crude antigen. Western blotting on two pure parasite proteins, dp72 and gp70-2, was also done. Mitogenic and antigen-specific stimulation of peripheral blood lymphocytes was monitored; and the haematological, clinical and parasitological parameters measured. Dogs challenged with amastigotes exhibited a more pronounced humoral response to leishmanial antigens. Only in one case was strong antigen-specific proliferation detected. Clinical signs of disease, including hypergammaglobulinaemia, enlarged lymph nodes and the presence of parasites, were also more apparent in the dogs challenged with amastigotes. None of the seven dogs died. Serum antibodies to leishmanial antigens were apparent between 1.5 to 3 months following challenge and correlated with the appearance of enlarged lymph nodes, hypergammaglobulinaemia and the presence of parasites in tissue biopsies. Serum antibodies remained chronically high in these dogs throughout the period of the study. Only one dog (1/3) challenged intravenously with promastigotes and the dog challenged intradermally with amastigotes produced transient antibody responses to leishmanial antigen. 相似文献
75.
76.
Kaisa Heiskanen Pirjo Lindstr m-Sepp Leena Haataja Sirkka-Liisa Vaittinen Terttu Vartiainen Hannu Komulainen 《Toxicology》1995,100(1-3):121-128
Activities of the xenobiotic metabolizing enzymes were measured in the liver, kidney, duodenum and lung microsomes and cytosol fractions of Wistar rats after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent bacterial mutagen in chlorinated drinking water. MX was administered by gavage at the dose level of 30 mg/kg for 18 weeks (low dose), or at the dose level which was raised gradually from 45 mg/kg for 7 weeks via 60 mg/kg for 2 weeks to a clearly toxic dose of 75 mg/kg for 5 weeks (high dose). Microsomal and cytosolic preparations were made and the activities of 7-ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), NADPH-cytochrome-c-reductase, UDP-glucuronosyltransferase (UDPGT) and glutathione-S-transferase (GST) were measured. Kidneys were affected most. A dose-dependent decrease was observed in EROD (90% in males, 80% in females at the high dose) and in PROD (58% in females, at the high dose) in kidneys. An increase was, however, detected in kidney NADPH-cytochrome-c-reductase (66% in females at high dose), UDPGT (89% in males and 97% in females at high dose) and GST activities (56% in males and 50% in females at high dose). MX caused only a few changes in the enzyme activities of the liver. The EROD activity was decreased 25% to 37%, both in the livers of males and females, but the total content of P450s was not altered. Hepatic GST activity was elevated in females in a dose-dependent manner (31% and 44%). GST activity was elevated in duodenum in females (59%) at the high dose. There were no marked changes in the enzyme activities in the lungs. MX was a weak inhibitor of EROD activity both in the liver and kidney microsomes in vitro, decreasing the EROD activity by 53% and 43%, respectively at the concentration of 0.9 mM. The results indicate that MX decreases the activity of phase I metabolism enzymes, but induces phase II conjugation enzyme activities, particularly in kidneys in vivo. It is possible that these changes contribute to metabolism of MX in kidneys and renders them susceptible to MX in the course of repeated exposure. 相似文献
77.
本文通过对多台日本光电公司遥测心电监护仪ZB-313P发射盒发射和接收石英晶体振荡器频率的实际测试以及对测试结果数据的分析研究。了解和掌握了其内在的规律,推导出了该发射盒的标称频率,实际发射频率以及监护仪接收频率三者之间关系变化的计算公式,以此公式计算出来的频率数据。可作为采用国产石英晶体振荡器对日本光电该系列监护仪进行维修的依据。并为此类设备的维修应用提供了一定的指导作用。 相似文献
78.
C. M. Morley 《Journal of human nutrition and dietetics》1992,5(6):399-407
The F.I.P. (Financial Information Project) dietetic package allows the collection of basic patient data, which then can be processed to give valuable clinical and management information for use by all dietitians in a dietetic department. The advent of the Korner Reports (DHSS, 1984a) and their implementation highlighted the need to computerize certain aspects of data collection in dietetic departments. Within the West Midlands Regional Health Authority a group of dietitians worked with the Regional Management Services Department to adapt a community nursing system, F.I.P., for use by dietitians. The system was piloted for all paramedical services in 1987 with one health district (North Warwickshire) piloting the dietetic package. It is now used by a range of dietetic and paramedical departments. This paper outlines the system and its uses. 相似文献
79.
Dental treatment is a dyadic encounter. Yet research on the dentist-patient dyad has tended to focus on patient perceptions of dentist, to the neglect of dentist perceptions of patient. Previous theoretic and qualitative work on caregiver perceptions of patients suggested three dimensions of evaluation. Dentists (N=618) rated their patients on items taken from two prior studies. Dentists' responses were subjected to confirmatory factor analysis. The analysis substantiated the existence of three evaluative dimensions: compliance, tractability, and likability. Further analysis showed that the three dimensions formed a Guttman simplex, revealing a second-order factor of selectivity and allowing a classification of dentists on the basis of patient selectivity.This study was funded by a grant from the University of Connecticut Research Foundation. 相似文献
80.
姜桂芳 《安徽卫生职业技术学院学报》2007,6(4):65-66
目的:为帮助腹腔镜胆囊手术病人掌握健康教育的知识.方法:开展了由腹腔镜手术后的病人向术前病人介绍手术感受.结果:促进术前病人对有关的健康教育知识的掌握,并能延长其术前1d晚的睡眠时间.结论:使病人更好地掌握健康宣教知识,有利于病人的治疗. 相似文献