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   3633篇
  免费   165篇
  国内免费   59篇
耳鼻咽喉   36篇
儿科学   88篇
妇产科学   60篇
基础医学   291篇
口腔科学   62篇
临床医学   315篇
内科学   332篇
皮肤病学   60篇
神经病学   391篇
特种医学   180篇
外科学   614篇
综合类   416篇
预防医学   311篇
眼科学   28篇
药学   467篇
  1篇
中国医学   87篇
肿瘤学   118篇
  2023年   56篇
  2022年   142篇
  2021年   155篇
  2020年   127篇
  2019年   153篇
  2018年   151篇
  2017年   111篇
  2016年   111篇
  2015年   120篇
  2014年   200篇
  2013年   220篇
  2012年   178篇
  2011年   192篇
  2010年   164篇
  2009年   181篇
  2008年   180篇
  2007年   141篇
  2006年   135篇
  2005年   119篇
  2004年   115篇
  2003年   107篇
  2002年   75篇
  2001年   63篇
  2000年   49篇
  1999年   53篇
  1998年   55篇
  1997年   33篇
  1996年   56篇
  1995年   30篇
  1994年   38篇
  1993年   29篇
  1992年   28篇
  1991年   30篇
  1990年   23篇
  1989年   23篇
  1988年   13篇
  1987年   11篇
  1986年   15篇
  1985年   23篇
  1984年   25篇
  1983年   9篇
  1982年   16篇
  1981年   14篇
  1980年   17篇
  1979年   10篇
  1978年   9篇
  1977年   7篇
  1976年   9篇
  1973年   7篇
  1972年   6篇
排序方式: 共有3857条查询结果,搜索用时 15 毫秒
101.
This article explores internet-related parent–child relationships across twenty-five European countries. Parent–child dyads are analysed in terms of parental mediation, digital competence, and communicative proximity, in order to answer the following research questions: Which types of parent–child relationship with respect to internet use can be found? How do they coincide with developmental, social, and cultural patterns? And how are they distributed across European Union countries? Using data from the EU Kids Online survey, four types of parent–child relationship were identified. The types are shaped by several factors on the level of child, family, and country, with the child's age and internet use being the most important predictors. Based on the prevalence of these family types, six country clusters were identified, which represent technical, social, and cultural contexts shaping the type of internet-related parent–child relationship.  相似文献   
102.
103.
104.
Rigid external distraction is currently used to correct severe maxillary hypoplasia. The purpose of this retrospective study was to present the clinical results and complications of a two-stage surgical approach using a modified external distraction system that consists of maxillary distraction and then maxillary fixation. We treated eight patients with cleft lip and palate in this way from 2016 to 2018. Lateral cephalograms taken before the first operation, after distraction, two weeks after the second operation, and one year after treatment were used to examine maxillofacial morphology. Velopharyngeal function was evaluated by a speech therapist. The mean movements of the maxilla forwards and downwards at Point A were 12.0 mm and 8.0 mm at the completion of distraction and those at Point B were 5.0 mm backwards and 9.7 mm downwards. Mouth opening was limited at this time, and was relieved after maxillary fixation. The mean relapse one year postoperatively was 24.3% horizontally and 52.5% vertically. Velopharyngeal function was unchanged by the operation. We conclude that the method has advantages that include the short duration of wearing distractors and increased acceptance by patients. The modified external device advanced the midface sufficiently.  相似文献   
105.
106.
Previous research suggests that criminal victimisation can impact negatively on both physical and psychological health. However, as yet, little is known about crime and its effects on population health in the former Soviet Union (fSU) – despite a sharp growth in crime rates in the countries in this region after the collapse of the communist system. Given this gap in current knowledge, this study examined two forms of crime, theft and violent victimisation, in nine fSU countries – Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Russia and Ukraine. Using nationally representative data from the Health in Times of Transition (HITT) study collected from 18,000 respondents in 2010/11, the study had two main objectives: (1) to identify which demographic and socioeconomic factors are associated with being a victim of crime; (2) to examine the relation between criminal victimisation and two health outcomes – self-rated health and psychological distress. We found that similar factors were associated with experiencing both forms of crime among respondents. Those who were younger, not married and who consumed alcohol more frequently were at increased risk of victimisation, while greater social capital was associated with lower odds for victimisation. Low education increased the risk of experiencing violence by 1.5 times. Victimisation was strongly associated with poorer health: victims of violence were 2.5 and 2.9 times more likely to report poor self-rated health and psychological distress, respectively, while the corresponding figures for theft victimisation were 1.9 and 1.8. The strong association we observed between criminal victimisation and poorer individual health suggests that, in addition to policies that reduce rates of crime, more research is now urgently needed on victimisation. Specifically, researchers should ascertain whether the association with poor health is causal, determine its potential mechanisms, and evaluate interventions that might mitigate its impact on health that are contextually appropriate in the fSU.  相似文献   
107.
A delayed haemolytic transfusion reaction (DHTR) encompasses a positive direct antiglobulin test (DAT) developed anytime between 24 hours to 28 days after cessation of transfusion, a positive eluate or a newly identified alloantibody in the plasma or serum along with features of haemolysis in the patient. Routinely, it is expected that with the transfusion of one unit of packed red cells in a patient of average height and weight, the haemoglobin level and hematocrit increase by 1 g/dL and 3% respectively. However, in a patient with DHTR, an inadequate rise of post-transfusion haemoglobin (< 1 g/dL) or rapid fall in haemoglobin back to pre-transfusion levels is observed. Kidd antibodies are particularly known to cause DHTR, maybe alone or in unison with other antibodies. Detection of these alloantibodies is consequential in providing good transfusion support to these patients. These events may be difficult to detect as they may present as varied clinical features or immunological nuisances. In this case series, we have presented three cases of DHTR with special emphasis on their clinical presentations, immunohaematological evaluations, laboratory parameters and the role of proper transfusion support in these patients to avoid further complications.  相似文献   
108.
ObjectiveThe aim of this review and meta-analysis was to evaluate the effect of heat and cold therapy on the treatment of delayed onset muscle soreness (DOMS).MethodsWe followed our protocol that was registered in PROSPERO with ID CRD42020170632. A systematic review and meta-analysis of randomized controlled trials (RCT) was conducted. Nine databases were searched up to December 2020. Data was extracted from the retained studies and underwent methodological quality assessment and meta-analysis.ResultsA total of 32 RCTs involving 1098 patients were included. Meta-analysis showed that, the application of cold therapy within 1 h after exercise could reduce the pain of DOMS patients within 24 h (≤24 h) after exercise (SMD -0.57,95%CI -0.89 to −0.25, P = 0.0005) and had no obvious effect within more than 24 h (>24 h) (P = 0.05). In cold therapies, cold water immersion (SMD -0.48, 95%CI -0.84 to −0.13, P = 0.008) and other cold therapies (SMD -0.68, 95%CI -1.28 to −0.08, P = 0.03) had the significant effects within 24 h. Heat treatment could reduce the pain of patients. It had obvious effects on the pain within 24 h (SMD -1.17, 95%CI -2.62 to −0.09, P = 0.03) and over 24 h (SMD -0.82, 95%CI -1.38 to −0.26, P = 0.004). Hot pack effect was the most obvious, which reduced the pain within 24 h (SMD -2.31, 95%CI -4.33 to −0.29, P = 0.03) and over 24 h (SMD -1.78, 95%CI -2.97 to −0.59, P = 0.003). Other thermal therapies were not statistically significant (P > 0.05). Both cold and heat showed effect in reducing pain of patients, however there was no significant difference between cold and heat group (P = 0.16).ConclusionsThe current evidence indicated that the application of cold and heat therapy within 1 h after exercise could effectively reduce the pain degree of DOMS patients for 24 h cold water immersion and hot pack therapy, which had the best effect, could promote the recovery of DOMS patients. But more high-quality studies are needed to confirm whether cold or heat therapy work better.  相似文献   
109.
ObjectiveThe Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.MethodsWe enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.ResultsThe 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.ConclusionsThe results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings.  相似文献   
110.
PurposeThe triple-H therapy is widely used for cerebral vasospasm (CV) prevention and treatment in patients after subarachnoid haemorrhage (SAH). However, this practice is based on low level evidence. Aim of this study was to evaluate errors in fluid administration, fluid balance monitoring and bedside charts completeness during a trial of triple-H therapy.Materials and methodsAn audit of the SAH patient charts was performed. A total of 508 fluid measurements were performed in 41 patients (6 with delayed cerebral ischaemia; DCI) during 14 days of observation.ResultsUnderestimating for intravenous drugs was the most frequent error (80.6%; 112), resulting in a false positive fluid balance in 2.4% of estimations. In 38.6% of the negative fluid balance cases, the physicians did not order additional fluids for the next 24 h. In spite of that, the fluid intake was significantly increased after DCI diagnosis. The mean and median intake values were 3.5 and 3.8 l/24 h respectively, although 40% of the fluid balances were negative. The positive to negative fluid balance ratio was decreasing in the course of the 14 day observation.ConclusionsThis study revealed inconsistencies in the fluid orders as well as mistakes in the fluid monitoring, which illustrates the difficulties of fluid therapy and reinforces the need for strong evidence-based guidelines for hypervolemic therapy in SAH.  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