全文获取类型
收费全文 | 3380篇 |
免费 | 231篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 193篇 |
妇产科学 | 147篇 |
基础医学 | 319篇 |
口腔科学 | 97篇 |
临床医学 | 478篇 |
内科学 | 579篇 |
皮肤病学 | 113篇 |
神经病学 | 184篇 |
特种医学 | 212篇 |
外科学 | 356篇 |
综合类 | 165篇 |
一般理论 | 5篇 |
预防医学 | 274篇 |
眼科学 | 64篇 |
药学 | 226篇 |
1篇 | |
中国医学 | 74篇 |
肿瘤学 | 101篇 |
出版年
2021年 | 43篇 |
2019年 | 38篇 |
2018年 | 39篇 |
2017年 | 42篇 |
2016年 | 46篇 |
2015年 | 63篇 |
2014年 | 87篇 |
2013年 | 91篇 |
2012年 | 105篇 |
2011年 | 129篇 |
2010年 | 101篇 |
2009年 | 90篇 |
2008年 | 123篇 |
2007年 | 115篇 |
2006年 | 108篇 |
2005年 | 108篇 |
2004年 | 104篇 |
2003年 | 80篇 |
2002年 | 60篇 |
2001年 | 76篇 |
2000年 | 73篇 |
1999年 | 54篇 |
1998年 | 60篇 |
1997年 | 68篇 |
1996年 | 65篇 |
1995年 | 57篇 |
1994年 | 63篇 |
1993年 | 49篇 |
1992年 | 42篇 |
1991年 | 42篇 |
1990年 | 52篇 |
1989年 | 65篇 |
1988年 | 67篇 |
1987年 | 66篇 |
1986年 | 61篇 |
1985年 | 50篇 |
1984年 | 49篇 |
1983年 | 41篇 |
1982年 | 31篇 |
1981年 | 43篇 |
1979年 | 31篇 |
1977年 | 23篇 |
1975年 | 28篇 |
1971年 | 28篇 |
1959年 | 36篇 |
1958年 | 62篇 |
1957年 | 91篇 |
1956年 | 46篇 |
1955年 | 76篇 |
1954年 | 67篇 |
排序方式: 共有3627条查询结果,搜索用时 453 毫秒
1.
宫腹腔镜联合手术诊治不孕症150例分析 总被引:14,自引:0,他引:14
目的:探讨宫腹腔镜联合手术在诊治不孕症中的应用。方法:对150例不孕症患者行宫腹腔镜联合手术,对不孕症病因进行诊断,同时行治疗。结果:盆腔粘连和输卵管阻塞是不孕症的主要原因。子宫内膜息肉和正常盆腔占次要比例。子宫内膜异位症和多囊卵巢也是主要病因。150例同时行宫腹腔镜输卵管通液和各种疾病的治疗。联合手术后妊娠率为48.8%。结论:腹腔镜联合手术,在一次麻醉下,可以对不孕的原因全面评价和明确诊断,在诊断同时进行治疗,对不孕症的诊断和治疗有重大的意义,值得推广。 相似文献
2.
3.
Harold C. Lyon Jr. James C. Healy James R. Bell Joseph F. O'Donnell Edward K. Shultz Robert S. Wigton Frank Hirai J. Robert Beck 《Journal of medical systems》1991,15(2):117-132
Richard E. Clark in his widely published comprehensive studies and meta-analyses of the literature on computer assisted instruction (CAI) has decried the lack of carefully controlled research, challenging almost every study which shows the computer-based intervention to result in significant post-test proficiency gains over a non-computer-based intervention. We report on a randomized study in a medical school setting where the usual confounders found by Clark to plague most research, were carefully controlled. PlanAlyzer is a microcomputer-based, self-paced, case-based, event-driven system for medical education which was developed and used in carefully controlled trials in a second year medical school curriculum to test the hypothesis that students with access to the interactive programs could integrate their didactic knowledge more effectively and/or efficiently than with access only to traditional textual “nonintelligent” materials. PlanAlyzer presents cases, elicits and critiques a student's approach to the diagnosis of two common medical disorders: anemias and chest pain. PlanAlyzer uses text, hypertext, images and critiquing theory. Students were randomized, one half becoming the experimental group who received the interactive PlanAlyzer cases in anemia, the other half becoming the controls who received the exact same content material in a text format. Later in each year there was a crossover, the controls becoming the experimentals for a similar intervention with the cardiology PlanAlyzer cases. Preliminary results at the end of the first two full trials shows that the programs have achieved most of the proposed instructional objectives, plus some significant efficiency and economy gains. 96 faculty hours of classroom time were saved by using PlanAlyzer in their place, while maintaining high student achievement. In terms of student proficiency and efficiency, the 328 students in the trials over two years were able to accomplish the project's instructional objectives, and the experimentals accomplished this in 43% less time than the controls, achieving the same level of mastery. However, in spite of these significant efficiency findings, there have been no significant proficiency differences (as measured by current factual and higher order multiple choice post-tests) between the experimental and control groups. Very careful controls were used to avoid what Clark has found to be the most common confounders of CAI research. Accordingly, this research proved Clark's rival hypothesis, that the computer, in itself, does not appear to contribute to proficiency gains, at least as measured by our limited post-testing. Clark's position is that the computer is primarily a vehicle—as is either a pill or a hypodermic needle for delivering a drug. The hypodermic needle can deliver the drug more efficiently than can the pill, (as can the computer deliver the subject matter content more efficiently, as our research indicates), but the same content is delivered. At the same time, we proved our own hypothesis, as far as efficiency gains resulting from the computer are concerned. However, going beyond Clark's research, we may be teaching processes both more effectively and efficiently with the computer (experience in problem-solving or clinical reasoning and pattern recognition) which our current post-tests do not adequately measure. Our on-going research suggests additional inquiry in several areas: better evaluation instruments to measure the clinical reasoning skills PlanAlyzer was designed to teach; the addition of more advanced cases to determine if this might transform efficiency gains of the computer group into proficiency gains; the addition of enhanced graphic decision support tools and other pedagogical enhancements including cognitive feedback to strengthen PlanAlyzer's power to teach complex concepts of medical decision-making. 相似文献
4.
5.
6.
Acute respiratory distress during Caesarean section under spinal anaesthesia A probable case of anaphylactoid reaction to Syntocinon 总被引:2,自引:0,他引:2
A case of life-threatening respiratory distress during a Caesarean section under spinal anaesthesia is reported. Possible causes of the event including anaphylactoid reactions and the methods of their diagnosis are discussed. The most likely cause of the episode was felt to be an anaphylactoid reaction to Syntocinon. 相似文献
7.
Symptom Clusters in Patients With High-Grade Glioma 总被引:2,自引:0,他引:2
8.
BACKGROUND AND AIM: Peptic ulcer disease is believed to be less common and less severe as a result of modern medical treatment. We therefore examined changes in the admission rates for patients with duodenal ulcer and gastric ulcer, both emergency (for haemorrhage, perforation or severe pain) and for elective surgery, before and since the introduction of the new advances in therapy. These admission indices reflect disease prevalence and severity. PATIENTS AND METHODS: We identified admission rates during 1972--2000 within the Trent Regional Health Authority, UK (population 4.7 million), from computerised patient information using diagnostic search codes ICD8-10 and expressed as rates per million resident population. Drug expenditure details were obtained from the Department of Health. RESULTS: Emergency admission rates as a whole changed little, a decline in the young being offset by an increase in the elderly. Haemorrhage was the most common reason (approximately 115 per million for duodenal ulcer and 87 for gastric ulcer) throughout [compared with perforation (80 and 21) and pain (90 and 68)]. In contrast, elective surgery has almost disappeared; this reduction began before the introduction of modern treatment. CONCLUSION: Emergency admission rates for duodenal and gastric ulcer for complications or severe pain have fluctuated over the last three decades but with little overall change. In contrast, elective surgery has declined dramatically, as a result of advances in treatment but also from changes in the natural history. 相似文献
9.
Abstract: This paper dicusses the use of esophageal dilatation with a Rigiflex TTS balloon. This method was used 45 times on 11 patients affected by anastomotic or a severe grade peptic esophageal stenosis. Fluoroscopic guidance was used in 36 procedures (80%) without effecting the mean duration of the treatment (12 minutes). The results were considered satisfactory when these goals had been achieved: a) dilatation of the stenosis over 15 mm; b) a dysphagia free-time of more than 6 months. A satisfactory result was achieved in 10 patients (90.9%), without deaths and major complications. 5 patients received 1 dilatation and the other 5 needed, 3-3-4-7–11 procedures respectively to obtain a satisfactory result. On these basis we consider that its great efficacy, security and tolerability depend on the following characteristics of the Rigiflex TTS balloon: 1) “radial” dilatation; 2) the possibility of introducing the balloon through the operative channel of the fiberscope; 3) direct visualization of the stenosis during dilatation. The following disadvantages with this method are: the absence of a tactile sensation of dilatation and the elevated cost of the instrument. We conclude that the Rigiflex TTS balloon is an important alternative to guide-wire techniques, especially for the treatment of severe esophageal strictures. 相似文献
10.
妊娠肝内胆汁淤积症患者血清一氧化氮和内皮素的变化及意义 总被引:2,自引:0,他引:2
目的:探讨妊娠肝内胆汁淤积症(ICP)患者外周静脉血清、新生儿脐静脉血清中一氧化氮(NO)、内皮素(ET)、丙二醛(MDA)和超氧化物歧化酶(SOD)含量的变化及在ICP发病中的作用。方法:以ICP组28例为研究组,测定其外周静脉血清及新生儿脐静脉血清中的NO、ET、MDA和SOD,以年龄相近的24例正常孕妇作为对照组。结果:ICP患者的MDA和ET含量较正常晚期妊娠显著增高(P<0.01),ICP患者的NO和SOD含量与对照组相比无显著性差异(P>0.05)。母血清中NO、ET、MDA含量均较新生儿脐静脉血清中的含量高,差异有显著性(P<0.01)。结论:妊娠期体内氧化和抗氧化失衡及ET水平的增高可能与ICP的发生、发展有关。 相似文献