首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   7061篇
  免费   714篇
  国内免费   21篇
耳鼻咽喉   120篇
儿科学   230篇
妇产科学   145篇
基础医学   1031篇
口腔科学   255篇
临床医学   691篇
内科学   1241篇
皮肤病学   93篇
神经病学   534篇
特种医学   247篇
外科学   977篇
综合类   185篇
一般理论   2篇
预防医学   760篇
眼科学   188篇
药学   515篇
中国医学   6篇
肿瘤学   576篇
  2021年   77篇
  2020年   71篇
  2019年   98篇
  2018年   142篇
  2017年   125篇
  2016年   121篇
  2015年   113篇
  2014年   157篇
  2013年   228篇
  2012年   294篇
  2011年   336篇
  2010年   198篇
  2009年   181篇
  2008年   312篇
  2007年   359篇
  2006年   323篇
  2005年   303篇
  2004年   314篇
  2003年   256篇
  2002年   256篇
  2001年   289篇
  2000年   276篇
  1999年   224篇
  1998年   129篇
  1997年   75篇
  1996年   86篇
  1995年   48篇
  1994年   71篇
  1993年   52篇
  1992年   192篇
  1991年   165篇
  1990年   130篇
  1989年   161篇
  1988年   154篇
  1987年   136篇
  1986年   138篇
  1985年   126篇
  1984年   79篇
  1983年   82篇
  1982年   40篇
  1981年   47篇
  1980年   46篇
  1979年   66篇
  1978年   75篇
  1977年   64篇
  1976年   46篇
  1975年   45篇
  1974年   43篇
  1973年   47篇
  1972年   47篇
排序方式: 共有7796条查询结果,搜索用时 15 毫秒
91.
Twenty-five patients, 16 with gastric cancer and nine with colonic cancer, received TNO-6 30 mg m?2 every four weeks. No objective tumour response was recorded. Nausea and vomiting occurred in 21 patients and was severe in 17. Severe marrow suppression developed in five patients. Renal function was unaffected in all but one patients who developed renal failure, probably as a result of septicaemia. However, the renal tubular enzymeN-acetyl-\-d-glucosaminidase was measured in six patients and showed a rise in all. In this study TNO-6 had no anti-tumour activity in gastrointestinal malignancy, but produced significant renal tubular damage.  相似文献   
92.
A Decision Support System should be approached, not as “starting over,” but as a natural extension of the design and development of a hospital's current HIS. Integrated, real-time HISs generate reams of information that, when combined with relevant external data, provide the essential information base for a hospital DDS. The Travenol Market Model is discussed as an example of a DSS specific to hospital needs.  相似文献   
93.
ObjectivesTo inform how the VA should develop and implement network adequacy standards, we convened an expert panel to discuss Community Care Network (CCN) adequacy and how VA might implement network adequacy standards for community care.Data Sources/Study settingData were generated from expert panel ratings and from an audio‐recorded expert panel meeting conducted in Arlington, Virginia, in October 2017.Study DesignWe used a modified Delphi panel process involving one round of expert panel ratings provided by nine experts in network adequacy standards. Expert panel members received a list of network adequacy standard measures used in commercial and government market and were provided a rating form listing a total of 11 measures and characteristics to rate.Data Collection MethodsItems on the rating form were individually discussed during an expert panel meeting between the nine expert panel members and VA Office of Community Care leaders. Attendees addressed discordant views and generated revised or new standards accordingly. Recorded audio data were transcribed to facilitate thematic analysis regarding opportunities and challenges with implementing network adequacy standards in VA Community Care.Principal FindingsThe five highest ranked standards were network directories for Veterans, regular reporting of network adequacy data to VA, maximum wait time/distance standards, minimum ratio of providers to enrolled population, and qualitative assessments of network adequacy. During the expert panel discussion with VA Community Care leaders, opportunities and challenges implementing network adequacy standards were highlighted.ConclusionsOur expert panel shed light on priorities for network adequacy to be implemented under CCN contracts, such as developing comprehensive provider directories for Veterans to use when selecting community providers. Remaining questions focus on whether the VA could reasonably develop and implement network adequacy standards given current Congressional restraints on VA reimbursement to community providers.  相似文献   
94.
95.
96.
C3H and C57Bl10 mice exhibit a differential susceptibility to arthritis induced by Mycoplasma pulmonis. Resistant C57Bl10 mice consistently demonstrated higher complement-fixing antibody titres than susceptible C3H mice throughout the development of the acute arthritis. A strong correlation was demonstrated between the levels of anti-mycoplasma antibody and resistance to acute arthritis in six strains of mice. To test the hypothesis that the difference of arthritis resistance of C3H and C57Bl10 mice was caused by a different susceptibility of their lymphocytes to mitogenic stimulation by M. pulmonis, we investigated the generation of non-specific immunoglobulin in vivo and in vitro. M. pulmonis acted as a polyclonal mitogen, but stimulated approximately equal responses in lymphocytes of both strains.  相似文献   
97.
Objective To study the relationship between human leukocyte antigen (HLA)-DRB1 and DQ alleles and the genetic susceptibility of type 1 diabetes in North Chinese children. Methods Polymerase chain reaction (PCR) techniques were used to amplify the second exon of DRB1 and DQ alleles, after which sequence specific olignucleotide probe (SSOP) dot blot hybridization techniques were used to analyze the amplified products. Results DRB1*0301, DQA1*0301, DQB1*0201 alleles and DRB1*0301-DQA1*0501-DQB1*0201 haplotype were significantly increased in patients, while DQA1*0103 and DQB1*0601 alleles were significantly increased in controls. The distribution of DR4 and DR9 haplotypes in patients and controls were not significantly different, but DR3/DR4 and DR4/DR9 heterozygotes were significantly increased in patients. Conclusions DRB1*0301, DQA1*0301 and DQB1*0201 confer susceptibility while DQA1*0103 and DQB1*0601 confer protection to type 1 diabetes. DRB1*0301-DQA1*0501-DQB1*0201 haplotype offers a predisposition to type 1 diabetes in North Chinese. Although the distribution of DR4 and DR9 in patients and controls had no significant difference, DR3/DR4 and DR3/DR9 heterozygotes were significantly increased in patients, showing that the susceptive effects of DR3 and DR4 or DR4 and DR9 haplotypes could be added up.  相似文献   
98.
We report a case of a giant squamous cell carcinoma of the hand. It demonstrates the natural history of a neglected well differentiated squamous cell tumour in this site. It resembles the epithelioma cuniculatum variant of squamous cell carcinoma, previously described as being peculiar to the foot. Correspondence to: Mr. C. McCormack.  相似文献   
99.
The purpose of this study was to investigate the effect of surface roughness on the relative corrosion rates of wires of four alloys-stainless steel, nickel titanium, cobalt chromium, and beta titanium. Batches of wire were divided into two groups. Wires in one group were industrially polished to provide a uniform surface finish; wires in the other group were left for comparison "as received." Wire diameter, hardness, and relative corrosion rates were compared within groups before and after polishing. Comparisons were also made across the four groups of alloys. The samples of as-received wires showed variations in surface finish, with beta titanium having the roughest appearance and cobalt chromium the smoothest. Nickel titanium and stainless steel surfaces were similar. Polishing provided a more uniform finish, but significantly reduced the diameter of the wires. Microhardness testing of wire surfaces of each alloy indicated that no significant work-hardening occurred as a result of polishing. The relative corrosion rates (expressed in terms of corrosion current density) in a 0.9% sodium chloride solution were estimated using the electrochemical technique of polarization resistance. Nickel titanium wires exhibited the greatest corrosion current density in the as-received state. Polishing significantly reduced the corrosion rate of nickel titanium, such that comparison between the four alloys in the polished state revealed no significant difference in their relative corrosion rate/corrosion current density.  相似文献   
100.
Cunningham SJ 《Dental update》1999,26(10):438-443
Facial attractiveness is now recognized as being important in situations as diverse as education, relationships and employment. An individual's facial appearance is one of their most obvious characteristics and facial disfigurements are judged to be among the least desirable 'handicaps'. A face which deviates from the norm becomes a stigma. This paper looks at the complex area of facial appearance and its importance in the field of dentistry. The relationship between facial attractiveness and varying forms of dental and surgical intervention are discussed, as well as some of the problems which may be encountered during treatment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号