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   1171篇
  免费   22篇
  国内免费   7篇
耳鼻咽喉   40篇
儿科学   51篇
妇产科学   145篇
基础医学   107篇
口腔科学   40篇
临床医学   85篇
内科学   180篇
皮肤病学   29篇
神经病学   44篇
特种医学   44篇
外科学   279篇
综合类   20篇
预防医学   21篇
眼科学   36篇
药学   42篇
中国医学   3篇
肿瘤学   34篇
  2024年   1篇
  2023年   6篇
  2022年   9篇
  2021年   22篇
  2020年   13篇
  2019年   25篇
  2018年   21篇
  2017年   23篇
  2016年   23篇
  2015年   34篇
  2014年   37篇
  2013年   72篇
  2012年   81篇
  2011年   85篇
  2010年   56篇
  2009年   73篇
  2008年   100篇
  2007年   114篇
  2006年   114篇
  2005年   93篇
  2004年   72篇
  2003年   38篇
  2002年   19篇
  2001年   21篇
  2000年   8篇
  1999年   18篇
  1998年   3篇
  1997年   3篇
  1996年   3篇
  1995年   3篇
  1992年   1篇
  1991年   2篇
  1990年   3篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
  1974年   1篇
排序方式: 共有1200条查询结果,搜索用时 15 毫秒
31.
[Purpose] The aim of this study was to investigate the effect of the addition of NMES to the post-TKA rehabilitation protocol on the functional status and quality of life of the patients. [Subjects and Methods] Patients were randomized into an exercise (control) and electrical stimulation (NMES) group. A home exercise program was prescribed for the control group. For the neuromuscular stimulation group 30 minute electrical stimulation applied to the vastus medialis muscle 5 days a week for 4 to 6 weeks. VAS, the timed up and go test, WOMAC and SF-36 scores were evaluated preoperatively and postoperatively at the first month and the third month of the follow-up period. [Results] Both the NMES group had 30 patients each, with 2 and 1 male patients respectively. The comparisons of WOMAC results at month 1 revealed that pain, stiffness, and total scores of the NMES group was significantly better than those of control group at the first and third months. Significantly better physical function and SF-36 subscales, except mental health, were found for the NMES group at the first month of follow-up. [Conclusion] The inclusion of the neuromuscular electrical stimulation program after knee arthroplasty was more effective at providing rapid improvements in knee pain, walking distance and quality of life.Key words: Quadriceps muscle, Knee joint, Arthroplasty  相似文献   
32.

PURPOSE

In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations.

MATERIALS AND METHODS

Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson''s correlation analysis was also performed to assess relationships between variables.

RESULTS

According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface.

CONCLUSION

Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings.  相似文献   
33.
34.
35.
The epsilon 4 (e4) isoform of apolipoprotein E (ApoE) is a known genetic risk factor for suboptimal brain health. Morphometry studies of brains with Alzheimer’s disease have reported significant alterations in temporal lobe brain structure of e4 carriers, yet it remains unclear if the presence of an e4 allele is associated with alterations in the microstructure of white matter fiber bundles in healthy populations. The present study used quantitative tractography based on diffusion tensor imaging (qtDTI) to examine the influence of the e4 allele on temporal lobe fiber bundle lengths (FBLs) in 64 healthy older adults with at least one e4 allele (carriers, N?=?23) versus no e4 allele (non-carriers, N?=?41). Subtests from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were also analyzed to examine memory performance between groups. Analyses revealed shorter FBLs in the left uncinate fasciculus (UF) (p?=?.038) of e4 carriers compared to non-carriers. By contrast, neither FBLs specific to the temporal lobe nor memory performances differed significantly between groups. Increased age correlated significantly with shorter FBL in the temporal lobe and UF, and with decreased performance on tests of memory. This is the first study to utilize qtDTI to examine relationships between FBL and ApoE genotype. Results suggest that FBL in the UF is influenced by the presence of an ApoE e4 allele (ApoE4) in healthy older adults. Temporal lobe FBLs, however, are more vulnerable to aging than the presence of an e4 allele.  相似文献   
36.
Purpose: Main causes of conversion to open surgery are uncontrolled bleeding from splenic hilum and capsular injury of spleen during laparoscopic splenectomy (LS). We present the use of LigaSure? in laparoscopic splenectomy for hemostasis.

Material &; Method: Between January 2005 and May 2006, LS was performed in a total of 29 patients (6 male and 23 female) with a mean age of 35.44 ± 13.63. Indications for splenectomy were idiopathic thrombocytopenic purpura (ITP) in 20 patients, thrombotic thrombocytopenic purpura (tTp) in 2, hereditary spherocytosis (HS) in 3, lymphan-gioma in 2, hodgkin lymphoma in 1 and splenic cyst in one patient. LS was performed in the right semilateral position with three 10 mm trocars. LigaSure? was used in dissection and division of splenic ligaments and hilar vascular structures.

Results: Conversion to open surgery was necessary in one patient due to peroperative bleeding. The mean duration of the operation was 71.3 ± 19.8 minutes and the estimated blood loss was 85 ± 23 ml. The diameter and the weight of the spleen were 10.7 ± 2.68 cm and 250 ± 90 g, respectively. There was no mortality. Postoperative complications included pancreatic fistula, trocar site infection and deep venous thrombosis that were encountered in three patients. These were managed without morbidity. The overall complication rate was 10.3% (n = 3). The mean duration of postoperative hospital stay was 2.86 ± 1.59 days.

Conclusion: LigaSure? use in LS had easy application, provided sufficient hemostasis, and shortened the operative time.  相似文献   
37.
38.
Purpose:The aim of this study was to evaluate the structural and functional changes occurring in patients with branch retinal vein occlusion (BRVO) according to the distance of the affected arteriovenous (AV) crossing to the centers of the fovea and optic disc by optic coherence tomography angiography (OCTA).Methods:Forty-five patients with unilateral BRVO and 45 age- and sex-matched healthy controls were included in this retrospective observational study. Images of the macula (3 mm × 3 mm) and affected AV crossing sites were obtained by OCTA. The fovea-AV crossing distance (FAVD), optic disc-AV crossing distance (DAVD), and optic disc-fovea distance (DFD) were measured.Results:The FAVD/DFD ratio was positively correlated with the vessel density in the superficial and deep affected hemifields (r = 0.430, P < 0.05 and r = 0.308, P < 0.05, respectively) and negatively correlated with the superficial foveal avascular zone and logarithm of the minimum angle of resolution (logMAR) visual acuity (r = –0.412, P < 0.05 and r = –0.356, P < 0.05, respectively). The DAVD/DFD ratio was not correlated with the logMAR visual acuity, superficial FAZ area or vessel densities in the affected hemifield (all P > 0.05).Conclusion:The affected AV crossing site that was further away from the fovea had better visual acuity and quantitative microvascular parameters in the affected hemifields. However, this correlation was not observed for the distance between the affected AV crossing site and the optic disc.  相似文献   
39.
40.
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