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   236360篇
  免费   16928篇
  国内免费   4424篇
耳鼻咽喉   1700篇
儿科学   4223篇
妇产科学   3937篇
基础医学   26468篇
口腔科学   4783篇
临床医学   21909篇
内科学   29213篇
皮肤病学   2797篇
神经病学   15197篇
特种医学   7366篇
外国民族医学   1篇
外科学   18368篇
综合类   29268篇
一般理论   19篇
预防医学   33566篇
眼科学   2549篇
药学   29251篇
  155篇
中国医学   13350篇
肿瘤学   13592篇
  2023年   3501篇
  2022年   5112篇
  2021年   9288篇
  2020年   9191篇
  2019年   9614篇
  2018年   9187篇
  2017年   9234篇
  2016年   8428篇
  2015年   7964篇
  2014年   11578篇
  2013年   16030篇
  2012年   12606篇
  2011年   14864篇
  2010年   9817篇
  2009年   9765篇
  2008年   11097篇
  2007年   11986篇
  2006年   10912篇
  2005年   9749篇
  2004年   8306篇
  2003年   7342篇
  2002年   5781篇
  2001年   5254篇
  2000年   4382篇
  1999年   3647篇
  1998年   2726篇
  1997年   2732篇
  1996年   2478篇
  1995年   2310篇
  1994年   2232篇
  1993年   1865篇
  1992年   1721篇
  1991年   1581篇
  1990年   1352篇
  1989年   1110篇
  1988年   1044篇
  1987年   961篇
  1986年   883篇
  1985年   1493篇
  1984年   1352篇
  1983年   1032篇
  1982年   1069篇
  1981年   921篇
  1980年   846篇
  1979年   710篇
  1978年   500篇
  1977年   409篇
  1976年   380篇
  1975年   308篇
  1974年   246篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
BackgroundPerianal abscesses and anal fistulas are common. The principle of intention-to-treat has not been considered in previous systemic reviews. Thus, the comparison between primary and post-recurrence management was confused, and the recommendation of primary treatment is obscure. The current study aims to identify the optimal initial treatment for pediatric patients.MethodsUsing PRISMA guidelines, studies were identified from MEDLINE, EMBASE, PubMed, Cochrane Library, and Google Scholar without any language or study design restriction. The inclusion criteria include original articles or articles with original data, studies of management for a perianal abscess with or without anal fistula, and patient age of <18 years. Patients with local malignancy, Crohn's disease, or other underlying predisposing conditions were excluded. Studies without analyzing recurrence, case series of <5, and irrelevant articles were excluded in the screening stage. Of the 124 screened articles, 14 articles had no full texts or detailed information. Articles written in a language other than English or Mandarin were translated by Google Translation first and confirmed with native speakers. After the eligibility process, studies that compared identified primary managements were then included in the qualitative synthesis.ResultsThirty-one studies involving 2507 pediatric patients met the inclusion criteria. The study design consisted of two prospective case series of 47 patients and retrospective cohort studies. No randomized control trials were identified. Meta-analyses for recurrence after initial management were performed with a random-effects model. Conservative treatment and drainage revealed no difference (Odds ratio [OR], 1.222; 95% Confidential interval [CI]: 0.615–2.427, p = 0.567). Conservative management had a higher risk of recurrence than surgery without statistical significance (OR 0.278, 95% CI: 0.109–0.707, p = 0.007). Compared with incision/drainage, surgery can prevent recurrence remarkably (OR 4.360, 95% CI: 1.761–10.792, p = 0.001). Subgroup analysis of different approaches within conservative treatment and operation was not performed for lacking information.ConclusionStrong recommendations cannot be made due to the lack of prospective or randomized controlled studies. However, the current study based on real primary management supports initial surgical intervention for pediatric patients with perianal abscesses and anal fistula to prevent recurrence.Level of evidenceType of study: Systemic review; Evidence level: Level II.  相似文献   
2.
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
3.
BackgroundPolypharmacy is commonly related to poor drug adherence, decreased quality of life and inappropriate prescribing in eldery. Furthermore, this condition also leads to a higher utilization of health services resources, due to the increased risk of adverse drug events, length of stays in hospitals and readmissions rates after discharge.ObjectiveThis Systematic Review aimed to synthesize the current evidence that evaluates pharmaceutical services on polymedicated patients, from an economic perspective.MethodsSystematic searches were conducted in MEDLINE, SCOPUS and Cochrane Library databases to identify studies that were published until January 2021. Experimental and observational studies were included in this review, using strict inclusion/exclusion criteria and were assessed for quality using the following tools: RoB and ROBINS-I. Two independent reviewers selected the articles and extracted the data.Results3,662 articles were retrieved from the databases. After the screening, 18 studies were included: 9 experimental and 9 observational studies. The studies reported that the integration of the pharmacist as a member of the healthcare team provides an optimized use of pharmacotherapy to polymedicated patients and contributes to health promotion, providing reduction of spending on medication, reduction of expenses related to emergency care and hospitalizations and other medical expenses. The ECRs made cost-effectiveness or cost-benefit analysis, and most of the Non Randomized studies had statistically significant cost savings even considering the expenses of pharmaceutical assistance. Experimental studies reported a cost reduction varying between US$ 193 to US$ 4,966 per patient per year. Furthermore, observational studies estimated a cost reduction of varying from US$ 3 to US$ 2,505 per patient per year. The cost savings are related to decrease in emergency visits and hospitalizations, through pharmacist intervention (medication review and pharmacotherapy follow-up).ConclusionsConsidering the set of studies included, pharmaceutical care services directed to polymedicated patients may cooperate to save financial resources. Most of the interventions showed positive economic trends and also contributed to improving clinical parameters and quality of life. However, due to the majority of the studies having exploratory or qualitative methodology, it is essential to carry out more robust studies, based on full economic evaluation.  相似文献   
4.
目的探讨对前列腺癌患者采用一体化管理老年综合评估(CGA)护理模式对其心理因素和生活质量的影响。方法选取2020年3月至2021年3月在南京市第一医院就诊,确诊为前列腺癌,且首次行腹腔镜下前列腺癌根治术的患者96例,随机分为对照组、观察1组、观察2组,各32例。对照组为住院后采用常规护理模式进行护理,观察1组为入院后行CGA干预组,观察2组为一体化管理的CGA干预组。三组患者分别在干预前、出院时,进行焦虑自评量表(SAS)、抑郁自评量表(SDS)测评;在干预前、术后30 d,进行生活质量核心量表QLQ-C30(V3.0)和前列腺癌特异性补充量表QLQ-PR25测评。结果出院时,观察2组SAS、SDS评分显著优于对照组及观察1组(P<0.05);术后30 d,观察2组生活质量QLQ-C30、QLQ-PR25评分显著优于对照组及观察1组(P<0.05)。结论一体化管理CGA护理模式可有效改善前列腺癌患者的心理状态,提高其术后生活质量。  相似文献   
5.
Racist policies and practices that restrict Black, as compared to white workers, from employment may drive racial inequities in birth outcomes among workers. This study examined the association between structural racism in labor markets, measured at a commuting zone where workers live and commute to work, and low-birthweight birth. We found the deleterious effect of structural racism in labor markets among US-born Southern Black pregnant people of working age, but not among African- or Caribbean-born counterparts in any US region. Our analysis highlights the intersections of structural racism, culture, migration, and history of racial oppression that vary across regions and birth outcomes of Black workers.  相似文献   
6.
7.
8.
9.
10.
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  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