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   238927篇
  免费   11868篇
  国内免费   423篇
耳鼻咽喉   3245篇
儿科学   7418篇
妇产科学   4924篇
基础医学   34362篇
口腔科学   5649篇
临床医学   18871篇
内科学   52966篇
皮肤病学   6299篇
神经病学   21279篇
特种医学   7129篇
外国民族医学   101篇
外科学   29899篇
综合类   1002篇
一般理论   62篇
预防医学   21697篇
眼科学   4706篇
药学   16699篇
中国医学   725篇
肿瘤学   14185篇
  2023年   1286篇
  2022年   943篇
  2021年   3637篇
  2020年   2156篇
  2019年   4058篇
  2018年   7629篇
  2017年   4990篇
  2016年   5036篇
  2015年   5636篇
  2014年   5964篇
  2013年   9493篇
  2012年   16462篇
  2011年   16434篇
  2010年   8227篇
  2009年   6132篇
  2008年   14081篇
  2007年   15040篇
  2006年   13884篇
  2005年   13697篇
  2004年   12834篇
  2003年   11690篇
  2002年   11059篇
  2001年   6194篇
  2000年   6280篇
  1999年   5574篇
  1998年   931篇
  1997年   763篇
  1996年   724篇
  1992年   3225篇
  1991年   2899篇
  1990年   2755篇
  1989年   2511篇
  1988年   2383篇
  1987年   2213篇
  1986年   2103篇
  1985年   1893篇
  1984年   1408篇
  1983年   1196篇
  1982年   677篇
  1979年   1212篇
  1978年   851篇
  1977年   798篇
  1975年   806篇
  1974年   989篇
  1973年   1001篇
  1972年   936篇
  1971年   923篇
  1970年   865篇
  1969年   906篇
  1968年   789篇
排序方式: 共有10000条查询结果,搜索用时 468 毫秒
91.
92.

Aim

The purpose of this study is to find out whether telephone referral from Primary Health Care to Internal Medicine Consult manages to reduce waiting days as compared to traditional referral. This study also aims to know how acceptable is the telephone referral to general practitioners and their patients.

Design

No blind randomized controlled clinical trial.

Setting

Northern Huelva Health District.

Participants

154 patients.

Interventions

Patients referrals from intervention clinicians were sent via telephone consultation, whereas patients referrals from control clinicians were sent by traditional via.

Measurements

Number of days from referral request to Internal Medicine Consult. Number of telephone and traditional referrals. Number of doctors and patients denied. Denial reasons.

Results

A statistically significant difference was found between groups, with an average of 27 (21-34) days. Among General Practitioners, 8 of the first 58 total doctors after randomization and, subsequently, 6 of the 20 doctors of the test group refused to engage in the trial because they considered “excessive time and effort consuming”. 50% of patients referred by the 14 General Practitioners finally randomized to the intervention group were denied referral by telephone due to patient's complexity.

Conclusions

Telephone referral significantly reduces waiting days for Internal Medicine consult. This type of referral did not mean an “excessive time and effort consuming” to General Practitioners and was not all that beneficial to complex patients  相似文献   
93.
94.
BACKGROUND Degree of portal hypertension(PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH(CSPH) and severe PH(SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient(HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.AIM To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.METHODS Of 36 patients with liver cirrhosis and measured HVPG were included in the casecontrol study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal(dantero, dretro, d RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain μ and standard deviation σ of strain were assessed in the regions of interest(ROI)(1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion(0-10 Hz and 10-20 Hz).RESULTS Four parameters showed statistically significant(P 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain(estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only dretro showed significant results in SPH analysis. According to ROC analysis area under the curve(AUC) of the σROI[0…10 Hz, 2 cm × 2 cm] parameter reached 0.71(P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for μROI[0…10 Hz, 1 cm × 1 cm] was 0.78(P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. Dretro parameter had an AUC of 0.86(P = 0.0001) for the diagnosis of CSPH and 0.84(P = 0.0001) for the diagnosis of SPH. A cut-off value of-132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.CONCLUSION The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH.  相似文献   
95.
96.
IntroductionPeople with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population.MethodsParticipants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards.ResultsFifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability.ConclusionsIOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS.  相似文献   
97.
98.
99.
100.
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