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   249篇
  免费   18篇
  国内免费   2篇
儿科学   5篇
妇产科学   5篇
基础医学   18篇
口腔科学   19篇
临床医学   17篇
内科学   66篇
皮肤病学   1篇
神经病学   13篇
特种医学   8篇
外科学   60篇
综合类   2篇
预防医学   3篇
眼科学   1篇
药学   21篇
中国医学   1篇
肿瘤学   29篇
  2024年   1篇
  2023年   3篇
  2022年   10篇
  2021年   16篇
  2020年   17篇
  2019年   20篇
  2018年   27篇
  2017年   7篇
  2016年   12篇
  2015年   9篇
  2014年   11篇
  2013年   18篇
  2012年   15篇
  2011年   19篇
  2010年   9篇
  2009年   12篇
  2008年   13篇
  2007年   15篇
  2006年   7篇
  2005年   4篇
  2004年   7篇
  2003年   2篇
  2002年   3篇
  2001年   1篇
  2000年   2篇
  1999年   2篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   3篇
排序方式: 共有269条查询结果,搜索用时 12 毫秒
41.
42.
43.

Background

A previous meta-analysis (MA) found postoperative radiotherapy (PORT) in lung cancer patients to be detrimental in N0/N1 patients and equivocal in the N2 setting. We hypothesized that treatment plans generated using MA protocols had worse dosimetric outcomes compared to modern plans.

Patients and Methods

We retrieved plans for 13 patients who received PORT with modern planning. A plan was recreated for each patient using the 8 protocols included in MA. Dosimetric values were then compared between the modern and simulated MA plans.

Results

A total of 104 MA plans were generated. Median prescribed dose was 50.4 (range, 50-60) Gy in the modern plans and 53.2 (30-60) Gy in the MA protocols. Median planning volume coverage was 96% (93%-100%) in the modern plans, versus 58% (0%-100%) in the MA plans (P < .001). Internal target volume coverage was 100% (99%-100%) versus 65% (0%-100%), respectively (P < .001). Organs at risk received the following doses: spinal cord maximum dose, 36.8 (4.6-50.4) Gy versus 46.8 (2.9-74.0) Gy (P < .001); esophageal mean dose, 22.9 (5.5-35) Gy versus 30.5 (11.1-52.5) Gy (P = .003); heart V30 (percentage of volume of an organ receiving at least a dose of 30 Gy), 16% (0%-45%) versus 35% (0%-79%) (P = .047); mean lung dose, 12.4 (3.4-24.3) Gy versus 14.8 (4.1-27.4) Gy (P = .008); and lung V20, 18% (4%-34%) versus 25% (8%-67%) (P = .023).

Conclusion

We quantitatively confirm the inferiority of the techniques used in the PORT MA. Our analysis showed a lower therapeutic ratio in the MA plans, which may explain the poor outcomes in the MA. The findings of the MA are not relevant in the era of modern treatment planning.  相似文献   
44.
TT virus (TTV) and TTV-like viruses (TTVLs) have been reported to be associated with non-A-E hepatitis. To determine the rate of infection and genotypic characteristics of TTV in the United Arab Emirates (UAE), a total of 449 serum samples representing different populations in the UAE and comprising healthy as well as patients positive for HBsAg and HCV were screened. National subjects (n = 200) and non-nationals residing in the UAE (n = 249) were tested by PCR. The results obtained showed that the rate of TTV infection in healthy nationals, and those with HBsAg or antibody to HCV were 34.9, 97.9, and 95.7, respectively, compared to 89.1% (115/129), 89.2% (66/74), and 84.8% (39/46), respectively, in non-nationals. Sequence analysis of the untranslated region (UTR) using 71 clones generated from the PCR products of eight serum samples from healthy individuals (four nationals and four non-nationals) showed that 83.1% of the TTV clones were classified into groups 1-4, whereas 16.9% into possibly new genotype(s). The analysis also revealed that healthy national subjects carried multiple viruses. Phylogenetic analysis of representative sequences revealed clustering of clones into at least five major groups. Also, when compared to reference genotypes (from GenBank), two of our clones belonged to two previously identified genotypes. Non-significant gender differences were seen in all ethnic groups studied (P > 0.05). In conclusion, the rate of TTV infection in the UAE nationals is significantly lower (P < 0.05) than that of the non-nationals and several genotypes were isolated with common multi-infections.  相似文献   
45.

Objectives

Monopolar transurethral resection of the prostate (TURP) is the gold standard surgical treatment for bothersome moderate to severe lower urinary tract symptoms (LUTS) secondary to benign prostate obstruction. The aim of the study is to compare monopolar versus bipolar TURP focusing on operative and functional outcomes, and evaluating complications with a long-term follow-up.

Methods

From January 2007 to July 2014, a total of 497 patients were randomized and prospectively scheduled to undergo bipolar (251) or monopolar (246) TURP. International prostate symptom score (IPSS), IPSS-Quality of life (QoL), post-void residual and maximum flow rate were assessed preoperatively and postoperatively at 3, 12, 24 and 36 months. Operative time, length of catheterization and hospitalization were all recorded. Complications were classified and reported.

Results

All patients completed the 36-month follow-up visit. Perioperative results showed no statistical significance between the two groups in terms of catheterization days, post-void residual, IPSS, IPSS-QoL score. The hospitalization length was found statistically significant in favor of the bipolar group. The 3-, 12-, 24- and 36-month follow-up showed significant and equal improvements in LUTS related to BPO in the two treatment groups. Regarding TURP complications, significant differences were observed in relation to urethral strictures, blood transfusion and TUR syndrome in favor of the bipolar group.

Conclusions

Monopolar and bipolar TURP are safe and effective techniques for BPH management. Bipolar TURP in our prospective study reported the same efficacy of monopolar prostate resection, with a significant reduction of related complications.
  相似文献   
46.
47.
Isolated TLA is an extremely rare condition, but should always be considered in a patient presented with liver abscess, especially from an endemic area. Diagnosis depends on histological identification, with treatment being quadruple therapy.  相似文献   
48.
Current understanding of the neural processes underlying human grasping suggests that grasp computations involve gradients of higher to lower level representations and, relatedly, visual to motor processes. However, it is unclear whether these processes evolve in a strictly canonical manner from higher to intermediate and to lower levels given that this knowledge importantly relies on functional imaging, which lacks temporal resolution. To examine grasping in fine temporal detail here we used multivariate EEG analysis. We asked participants to grasp objects while controlling the time at which crucial elements of grasp programs were specified. We first specified the orientation with which participants should grasp objects, and only after a delay we instructed participants about which effector to use to grasp, either the right or the left hand. We also asked participants to grasp with both hands because bimanual and left-hand grasping share intermediate-level grasp representations. We observed that grasp programs evolved in a canonical manner from visual representations, which were independent of effectors to motor representations that distinguished between effectors. However, we found that intermediate representations of effectors that partially distinguished between effectors arose after representations that distinguished among all effector types. Our results show that grasp computations do not proceed in a strictly hierarchically canonical fashion, highlighting the importance of the fine temporal resolution of EEG for a comprehensive understanding of human grasp control.SIGNIFICANCE STATEMENT A long-standing assumption of the grasp computations is that grasp representations progress from higher to lower level control in a regular, or canonical, fashion. Here, we combined EEG and multivariate pattern analysis to characterize the temporal dynamics of grasp representations while participants viewed objects and were subsequently cued to execute an unimanual or bimanual grasp. Interrogation of the temporal dynamics revealed that lower level effector representations emerged before intermediate levels of grasp representations, thereby suggesting a partially noncanonical progression from higher to lower and then to intermediate level grasp control.  相似文献   
49.
50.
We report a newborn female baby who presented at 6 hours of age with cyanosis without any signs of respiratory distress. Cardiovascular and systemic examination was unremarkable apart from cyanosis (saturation 75%). An echocardiogram showed multiple echogenic and homogeneous masses in the interventricular septum, one of which was big and protruding through the tricuspid valve causing right ventricular inflow obstruction. There was a small atrial septal defect (ASD) shunting right to left and patent ductus arteriosus (PDA) shunting left to right. The provisional diagnosis was rhabdomyoma. Blalock-Taussig shunt was done to preserve the tricuspid valve, because these masses tend to regress spontaneously, which was the case after few months. Subsequently, the patient was diagnosed with tuberous sclerosis.  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