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   95802篇
  免费   8339篇
  国内免费   6580篇
耳鼻咽喉   754篇
儿科学   1275篇
妇产科学   972篇
基础医学   9897篇
口腔科学   2094篇
临床医学   12077篇
内科学   12905篇
皮肤病学   1108篇
神经病学   4658篇
特种医学   3859篇
外国民族医学   36篇
外科学   11230篇
综合类   18459篇
现状与发展   18篇
一般理论   15篇
预防医学   7077篇
眼科学   2127篇
药学   9735篇
  84篇
中国医学   5428篇
肿瘤学   6913篇
  2024年   340篇
  2023年   1319篇
  2022年   3280篇
  2021年   4436篇
  2020年   3496篇
  2019年   2872篇
  2018年   3061篇
  2017年   2877篇
  2016年   2545篇
  2015年   4176篇
  2014年   5419篇
  2013年   5423篇
  2012年   7889篇
  2011年   8477篇
  2010年   6149篇
  2009年   5330篇
  2008年   6014篇
  2007年   5731篇
  2006年   5520篇
  2005年   4962篇
  2004年   3426篇
  2003年   3049篇
  2002年   2501篇
  2001年   1958篇
  2000年   1847篇
  1999年   1753篇
  1998年   948篇
  1997年   996篇
  1996年   704篇
  1995年   634篇
  1994年   565篇
  1993年   378篇
  1992年   431篇
  1991年   381篇
  1990年   308篇
  1989年   270篇
  1988年   249篇
  1987年   209篇
  1986年   189篇
  1985年   127篇
  1984年   75篇
  1983年   80篇
  1982年   49篇
  1981年   55篇
  1980年   31篇
  1979年   47篇
  1978年   21篇
  1977年   18篇
  1974年   19篇
  1973年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation.  相似文献   
13.
BACKGROUND AND PURPOSE: Health-related quality of life (HRQOL) is primarily an assessment of how domains of life are affected by health. This study investigated the factors influencing HRQOL of Taiwanese patients with bronchial asthma. METHODS: A cross-sectional study was conducted to assess the factors influencing HRQOL. The sample consisted of 242 outpatients with bronchial asthma. The Chinese language version of the St. George's Respiratory Questionnaire was used to measure HRQOL. Data were analyzed using simple regression and multiple regression. RESULTS: Age, marital status, level of education, asthma severity, peak expiratory flow, and previous hospital admissions were found to be predictors of HRQOL. Gender, duration of disease, and history of emergency visits were not correlated with HRQOL. The variables entered in the HRQOL model accounted for 17.4% of the total variance (adjusted R(2)). The regression coefficients indicated that the mean scores increased 7.68 in patients with moderate to severe disease severity, and increased 7.34 in patients with a history of hospital admissions. The mean scores decreased 7.60 in married patients. CONCLUSION: This study found that marital status, asthma severity, and history of hospital admissions were major predictors of HRQOL in Taiwanese patients with bronchial asthma.  相似文献   
14.
15.
王焕禄老中医在长期的临床实践中,总结出治疗哮喘病的一些用药体会,兹介绍如下,以飨读者。  相似文献   
16.
Objective To evaluate the clinical effect of placing double J stent using a ureteroscope in early managing ureterovaginal fistula.Methods Twenty-eight patients cases with ureterovaginal fistula from 2002 to 2008 were treated early with placing double J stent using a ureteroscope and the clinical data were reviewed.Results Twenty-two of 28 cases were treated and double J stent was placed in them by a uretero-scope and 75% (21/28)of cases were cured.Four of 21 cases were treated twice by a ureteroscope and were cured finally.7 cases with failure ureterovaginal treatment underwent ureterocystostomy and were cured.The follow-up from 6 months to 33 months (average 10.1±6.4 months)showed that all of the 28 cases had been cured and had no urinary fistula.Conclusion Placing double J stent using a ureteroscope is the first choice of operative procedure for the early treatment of ureterovaginal fistula.  相似文献   
17.
SUMMARY: It is desirable to estimate epileptogenic zones with both location and extent information from noninvasive EEG. In the present study, the authors use a subspace source localization method (FINE), combined with a local thresholding technique, to achieve such tasks. The performance of this method was evaluated in interictal spikes from three pediatric patients with medically intractable partial epilepsy. The thresholded subspace correlation, which is obtained from FINE scanning, is a favorable marker, which implies the extents of current sources associated with epileptic activities. The findings were validated by comparing the results with invasive electrocorticographic (ECoG) recordings of interictal spike activity. The surgical resections in these three patients correlated well with the epileptogenic zones identified from both EEG sources and ECoG potential distributions. The value of the proposed noninvasive technique for estimating epileptiform activity was supported by satisfactory surgery outcomes.  相似文献   
18.
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination.  相似文献   
19.
Previous work has shown that alterations in proteoglycan aggregates are among the first changes detected with aging, disuse, and degeneration of articular cartilage, yet the cause or causes of these alterations remain unknown. To determine if differences in link protein concentration can explain alterations in the assembly, size, and stability of articular cartilage proteoglycan aggregates, we isolated proteoglycan monomer (aggrecan) and link protein from adult bovine articular cartilage and then assembled proteoglycan aggregates from aggrecan and 0.8% hyaluronan relative to aggrecan weight, in the presence of 0, 2, 4, 6, 8, 10, 15, and 20% concentrations of link protein relative to aggrecan weight. We determined the amount, sedimentation coefficient, and stability of the aggregates by analytical ultracentrifugation and measured their dimensions by electron microscopy with use of the monolayer technique. Increased aggregate size, as determined by ultracentrifugation, was directly correlated with an increased number of aggrecans per aggregate and with increased hyaluronan length, as determined by electron microscopy. The concentration of link protein significantly influenced aggregation: concentrations of 6–8% produced maximum aggregation, aggregate stability, and uniformity of aggrecan spacing; concentrations greater than 10% led to the formation of superaggregates (aggregates with sedimentation velocities greater than 100 S that may result from linking two or more hyaluronan filaments) but decreased aggregate stability; and concentrations of less than 4% link protein significantly decreased aggregation, the size and stability of aggregates, and the regularity of aggrecan spacing. The latter observations suggest that a decline in the concentration of link protein could decrease the organization and stability of the articular cartilage matrix.  相似文献   
20.
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