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   221224篇
  免费   19410篇
  国内免费   4671篇
耳鼻咽喉   3346篇
儿科学   4238篇
妇产科学   3633篇
基础医学   19516篇
口腔科学   7261篇
临床医学   20002篇
内科学   20604篇
皮肤病学   2425篇
神经病学   16067篇
特种医学   5825篇
外国民族医学   11篇
外科学   20900篇
综合类   34270篇
现状与发展   11篇
一般理论   25篇
预防医学   28250篇
眼科学   2070篇
药学   21499篇
  331篇
中国医学   25950篇
肿瘤学   9071篇
  2024年   706篇
  2023年   4210篇
  2022年   7160篇
  2021年   10763篇
  2020年   10308篇
  2019年   11760篇
  2018年   10432篇
  2017年   9038篇
  2016年   8081篇
  2015年   7559篇
  2014年   14827篇
  2013年   15476篇
  2012年   13369篇
  2011年   14411篇
  2010年   11578篇
  2009年   10136篇
  2008年   9489篇
  2007年   9523篇
  2006年   8162篇
  2005年   6878篇
  2004年   5752篇
  2003年   5072篇
  2002年   3941篇
  2001年   3289篇
  2000年   2881篇
  1999年   2373篇
  1998年   1934篇
  1997年   1741篇
  1996年   1425篇
  1995年   1374篇
  1994年   1219篇
  1993年   1068篇
  1992年   988篇
  1991年   893篇
  1990年   785篇
  1989年   740篇
  1988年   689篇
  1987年   610篇
  1986年   565篇
  1985年   1865篇
  1984年   2122篇
  1983年   1335篇
  1982年   1763篇
  1981年   1230篇
  1980年   1041篇
  1979年   933篇
  1978年   765篇
  1977年   584篇
  1976年   726篇
  1975年   508篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.

Background

Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.

Methods

A total of 1,331 consecutive patients at a single academic institution were reviewed from a prospectively collected database. Preoperative data collected included demographics, body mass index, and percent excess weight loss. Postoperative BMI and %EWL were collected at 12, 24, and 36 months. Percent excess weight loss was analyzed by the percentiles of excess weight lost, and the distribution of percent excess weight loss was evaluated in 10% increments. Lack of a successful treatment effect was defined as <25% excess weight loss.

Results

Of the 1,331 patients, 72.4% (963) underwent laparoscopic Roux-en-Y gastric bypass, 18.3% (243) laparoscopic sleeve gastrectomy, and 9.4%(125) laparoscopic adjustable gastric banding. Mean percent excess weight loss was greatest for laparoscopic Roux-en-Y gastric bypass, followed by laparoscopic sleeve gastrectomy, and then by laparoscopic adjustable gastric banding at every time point: at 2 years mean percent excess weight loss was 77.9± 24.4 for laparoscopic Roux-en-Y gastric bypass, 50.8 ± 25.8 for laparoscopic sleeve gastrectomy, and 40.8± 25.9 for laparoscopic adjustable gastric banding (P < .0001). The rates of a successful treatment effect s for laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding were 0.9%, 5.2%, and 24.3% at 1 year; 0.3%, 11.1%, and 26.0% at 2 years; and 1.0%, 25.3%, and 30.2% at 3 years. At 1 year, the odds ratio of lack of a successful treatment effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass was 6.305 (2.125–19.08; P?=?.0004), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass was 36.552 (15.64–95.71; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy was 5.791 (2.519–14.599; P < .0001). At 2 years, the odds ratio for laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass increased to 70.7 (9.4–531.7; P < .0001), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass increased to 128.1 (16.8–974.3; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy decreased to 1.8 (0.9–3.6; P?=?.09).

Conclusion

This study emphasizes the existing variability in weight loss across bariatric procedures as well as in the lack of a treatment effect for each procedure. Although laparoscopic adjustable gastric banding has the greatest rate of a lack of a successful treatment effect, the rate remained stable over 3 years postoperatively. Laparoscopic sleeve gastrectomy showed a doubling in the rate of a lack of a successful treatment effect every year reaching 25% at year 3. The rates for lack of a successful treatment effect for laparoscopic Roux-en-Y gastric bypass remained stable at about 1% for the first 3 years postoperatively.  相似文献   
92.

Background

Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.

Methods

During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.

Results

No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.

Conclusions

The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach.  相似文献   
93.
《The surgeon》2022,20(1):16-40
Surgical Innovations are central to surgical progress, and have led to exponential growth in various fields of Surgery. Surgical Innovations in Lower and Middle Income Countries are the result of creativity of frontline health workers in search of simple, safe and ethical solutions for their unique challenges. The key lies in: ‘simplifying the idea/technique/device’ to find patients' needs-driven low-cost innovative surgical solutions; which can be used on a wider scale to achieve health equity for underserved populations. Local surgeons understand the difficulties and nuances of various problems and can provide local-evidence-based customized solutions for their patients' health problems. We developed a Surgical Innovation Ecosystem allowing us to see difficulties as opportunities, learn from everyone and conduct research on what is ‘important’ rather than what is ‘interesting’. Barriers to Surgical Innovations in Lower and Middle Income Countries are well known; however, a roadmap to overcome these barriers is now available. The right balance has to be found between encouraging creativity and innovation while maintaining ethical awareness and responsibility to patients. Introduction and adoption of Surgical Innovations are governed by evidence-based principles and have to undergo a rigorous and scientific evaluation. Science of Surgical Innovations has finally come of age and is getting its due recognition and the pioneering innovators are receiving the much needed appreciation and support.  相似文献   
94.
ObjectiveTo estimate the prospective relationships between exposure to psychosocial risks dimensions included in the COPSOQ-Istas21 and the deterioration of general and mental health and sleep problems among workers residing in Spain.MethodCohort whose baseline corresponds to the 2016 Psychosocial Risks Survey with a new measurement after one year.ResultsSocial capital and interpersonal relations and leadership dimensions, as well as work?life conflict, were related to all health variables. Dimensions of work organization and job contents did it especially with the mental health, the quantitative demands with the general health and the emotional ones with the mental health. The dimensions related to job insecurity did not show relationships with health.ConclusionsThe results obtained reinforce the role of the COPSOQ-Istas21 as a useful instrument for the evaluation and prevention of psychosocial risks at work.  相似文献   
95.
96.
97.
Effective communication between clinicians, patients, and families at end of life is associated with better clinical outcomes. A large body of literature describes the key skills needed for effective communication. We believe that clinicians could also benefit from communication skills more commonly associated with business or law negotiations. We will demonstrate via analogy (i.e. buying a house) how four key business/law negotiation techniques – 1. Determine your Reservation and Aspiration Value; 2. Separate People from their Positions; 3. Separate Positions from Interests; and 4. Logrolling of Interests – can be applied to a difficult family meeting in a home hospice patient.  相似文献   
98.
中西医结合治疗动眼神经麻痹疗效观察   总被引:2,自引:0,他引:2  
目的了解中西医结合法治疗动眼神经麻痹的临床疗效。方法对我院2012-03—2014-03收治的动眼神经麻痹患者进行抽样,择取74例患者随机分成2组,对照组予以基础性西医疗法,实验组在对照组治疗基础上予以中医疗法(包括针刺及服用中药正容汤等),观察2组患者的临床治疗效果。结果实验组总有效率(94.60%)明显高于对照组(64.86%),差异具有统计学意义(P0.05)。结论中西医结合法治疗动眼神经麻痹临床疗效确切,安全系数高,值得临床大力推广使用。  相似文献   
99.
100.
目的:探讨益气通脉饮治疗气虚血瘀型冠心病心绞痛的临床疗效。方法:选取2017年10月—2019年2月烟台业达医院收治的气虚血瘀型冠心病心绞痛的患者90例作为研究对象,根据随机数字表法将所选患者均分为两组,每组各45例,两组的一般资料经统计学方法,差异无统计学意义(P>0.05),因此具有可比性。对照组给予常规西药进行治疗,观察组在对照组治疗基础上给予益气通脉饮治疗,1个月后比较两组临床的疗效,评估治疗前后中医证候、心绞痛症状分级和血脂水平。临床检测的数据通过统计产品与服务解决方案(Statistical Product and Service Solutions,SPSS) 19.0软件进行分析和处理,计量的数据使用平均数±标准差(x±s)表示,采用双侧t检验,计数的数据采用χ~2检验,以%表示,以P<0.05为差异有统计学意义。结果:治疗后,对照组和观察组都有一定疗效,但观察组的改善中医证候总有效率95.56%(43/45),高于对照组的82.22%(37/45),两组比较具有统计学意义(P<0.05);心绞痛的症状总有效率观察组为93.33%(42/45),对照组为77.78%(35/45),两组比较差异有统计学意义(P<0.05);与治疗前相比较,两组治疗后的三酰甘油(Triglyceride,TG)、血清总胆固醇(Serum Total Cholesterol,TC)、高密度脂蛋白胆固醇(High Density Liptein Cholesterol,HDL-C)水平均降低(P<0.05),且观察组治疗后低于对照组(P<0.05),两组治疗后的HDL-C升高(P<0.05),组间比较,差异无统计学意义(P>0.05)。结论:益气通脉饮治疗气虚血瘀型冠心病心绞痛的疗效显著,值得临床进一步研究与推广应用。  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