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   8274篇
  免费   613篇
  国内免费   21篇
耳鼻咽喉   63篇
儿科学   294篇
妇产科学   265篇
基础医学   1031篇
口腔科学   127篇
临床医学   1145篇
内科学   1432篇
皮肤病学   127篇
神经病学   750篇
特种医学   212篇
外科学   826篇
综合类   64篇
一般理论   16篇
预防医学   1152篇
眼科学   113篇
药学   604篇
中国医学   13篇
肿瘤学   674篇
  2024年   23篇
  2023年   113篇
  2022年   124篇
  2021年   231篇
  2020年   199篇
  2019年   243篇
  2018年   258篇
  2017年   214篇
  2016年   261篇
  2015年   253篇
  2014年   311篇
  2013年   467篇
  2012年   675篇
  2011年   744篇
  2010年   369篇
  2009年   299篇
  2008年   558篇
  2007年   540篇
  2006年   542篇
  2005年   499篇
  2004年   374篇
  2003年   412篇
  2002年   360篇
  2001年   78篇
  2000年   45篇
  1999年   63篇
  1998年   66篇
  1997年   46篇
  1996年   48篇
  1995年   37篇
  1994年   43篇
  1993年   33篇
  1992年   39篇
  1991年   20篇
  1990年   34篇
  1989年   24篇
  1988年   15篇
  1987年   16篇
  1986年   21篇
  1984年   11篇
  1983年   16篇
  1982年   17篇
  1981年   16篇
  1980年   9篇
  1979年   18篇
  1978年   11篇
  1977年   11篇
  1976年   9篇
  1975年   11篇
  1974年   17篇
排序方式: 共有8908条查询结果,搜索用时 15 毫秒
101.
102.
Journal of Clinical Immunology - T cell-Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis (T cell-EBV-HLH) is prevalent in East Asia and has poor prognosis. Understanding of...  相似文献   
103.
ObjectiveTo evaluate responses by people with knee osteoarthritis to a brief educational video about their condition that aimed to empower and motivate effective self-management. The video content addressed psychosocial contributors to pain and barriers to behaviour change.MethodsA mixed methods design, including a survey and semi-structured interviews, was used to collect data from 118 people (46–83 years, 78% female) with knee osteoarthritis.ResultsQuantitative data analysis showed the video was rated positively on 0–6 scales for enjoyability (mean 5.0), helpfulness (4.9), relevance (5.0) and believability (5.4). The majority would recommend the video (89%), learned new information (78%) and/or reported intentions to change behaviour (78%). A minority disliked aspects of the video (23%). The thematic analyses identified three main themes: Reactions to the video, including emotions; Learning from the video, including new knowledge and empowerment, but also unmet information needs or disagreement; and Intentions, including behaviour changes, cognitive changes and help seeking.ConclusionEducation about knee osteoarthritis with a focus on empowerment is well received by people with the condition, although some discordant views emerged.Practice implicationsThe educational video about knee osteoarthritis can be recommended to promote effective self-management and counteract potential drawbacks associated with biomedical-based education.  相似文献   
104.
105.
106.
This study examined narrative representations of parents and of self, as well as child behavior during the assessment, in maltreated (N = 56) and demographically comparable non-maltreated (N = 37) pre-school-aged children in a one-year longitudinal study. Maltreated children evidenced more negative representations of parents and of self at Time 2, including the juxtaposition of both a negative and a grandiose self. Over time there was a marginal interaction such that maltreated children portrayed fewer disciplining parent representations and nonmaltreated children portrayed more. Also over time, maltreated children portrayed marginally more grandiose self-representations and nonmaltreated children fewer. Furthermore, maltreated children demonstrated less responsivity to the examiner over time and nonmaltreated children demonstrated more. The deleterious effects of maltreatment on representations of self and of others, especially as development proceeds, are discussed, and the importance of providing attachment-informed intervention prior to the consolidation of these negative representations is highlighted.  相似文献   
107.
BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes.  相似文献   
108.
BackgroundPressure injuries have a major impact on patients and healthcare organisations. The complications of pressure injuries increase morbidity and mortality rates and are costly to individuals and healthcare systems. The total prevalence rate of pressure injuries within acute care hospitals in Australia and New Zealand is unknown, and despite a focus on prevention, pressure injuries still occur within these hospital settings.AimTo report the prevalence of pressure injuries within acute care settings in Australian and New Zealand hospitals and to identify the stage and location of pressure injuries and analyse the methods used to conduct pressure injury point prevalence studies.MethodsA systematic review of studies published in CINAHL, MEDLINE and Cochrane databases and a two-part grey literature search, including a customised Google search and a targeted website search, was undertaken up to July 2019. The systematic review was prospectively registered with PROSPERO (CRD42018105566).FindingsThe overall prevalence of pressure injuries in acute-care hospitals in Australia and New Zealand is 12.9% (95% CI, 9.5%–16.8%) and the hospital-acquired pressure injury prevalence is 7.9% (95% CI, 5.7%–10.3%). Stage I and stage II are the most common pressure injuries. The most frequent locations for pressure injuries are the sacrum/buttock/coccyx area (41%) and the heels (31%). The reporting of details about methodology varies considerably between studies.DiscussionPressure injuries remain a significant problem within acute-care hospital settings. Total prevalence rates are decreasing over time with the numbers of stage I and II pressure injuries decreasing faster than other pressure injuries.ConclusionThe findings from this study can be used to set performance benchmarks within acute-care hospitals in Australia and New Zealand. Pressure injuries are preventable and pressure injury prevalence studies can be used to monitor the effectiveness of nursing care processes to improve patient outcomes.  相似文献   
109.

Background and Purpose

The purpose of this study was to estimate the incidence and prevalence of epilepsy among an elderly and poor population in the United States.

Methods

Arizona Medicaid claims data from January 1, 2008 to December 31, 2010 were used for this analysis. Subjects who were aged ≥65 years and were continuously enrolled in any Arizona Medicaid health plans (eligible to patients with low income) for ≥12 months between January 1, 2008 and December 31, 2009 were considered eligible for inclusion in the study cohort. In addition to meeting the aforementioned criteria, incident and prevalent cases must have had epilepsy-related healthcare claims. Furthermore, incident cases were required to have a 1-year "clean" period immediately preceding the index date. Negative binomial and logistic regression models were used to assess the factors associated with epilepsy incidence and prevalence.

Results

The estimated epilepsy incidence and prevalence for this population in 2009 were 7.9 and 19.3 per 1,000 person-years, respectively. The incidence and prevalence rates were significantly higher for patients with comorbid conditions that were potential risk factors for epilepsy and were of younger age than for their non-comorbid and older counterparts (p<0.05). The prevalence rates were significantly higher for non-Hispanic Blacks and male beneficiaries than for non-Hispanic Whites and female beneficiaries, respectively (p<0.05).

Conclusions

This patient population had higher epilepsy incidence and prevalence compared with the general US population. These differences may be at least in part attributable to their low socioeconomic status.  相似文献   
110.
Chicken muscle beta-actinin is considered to be one of the "true" myofibrillar components due to its specific binding to isolated myofibrils. Surprisingly, the direct comparison of this muscle protein with serum albumin, both isolated from chicken, showed that they behaved identically under several electrophoretic conditions. Furthermore, immunoreplica gels and double-immunodiffusion tests with antibodies prepared against beta-actinin established the serological identity of both proteins. No significant differences were found by circular dichroic spectroscopy or in amino acid composition. In addition, the amino-terminal sequences of both proteins were identical (H2N-Asp-Ala-Glu-His-Lys-Ser-Glu-Ile-Ala-His-Arg-Tyr-Asn-Asp-Leu-). Combined, these results strongly indicate that muscle beta-actinin and serum albumin are similar, if not identical.  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