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   1158篇
  免费   39篇
  国内免费   5篇
耳鼻咽喉   4篇
儿科学   9篇
妇产科学   12篇
基础医学   138篇
口腔科学   48篇
临床医学   100篇
内科学   212篇
皮肤病学   12篇
神经病学   83篇
特种医学   16篇
外科学   354篇
综合类   1篇
预防医学   13篇
眼科学   8篇
药学   46篇
肿瘤学   146篇
  2023年   6篇
  2022年   14篇
  2021年   24篇
  2020年   7篇
  2019年   17篇
  2018年   28篇
  2017年   26篇
  2016年   19篇
  2015年   27篇
  2014年   38篇
  2013年   49篇
  2012年   79篇
  2011年   75篇
  2010年   40篇
  2009年   44篇
  2008年   71篇
  2007年   70篇
  2006年   55篇
  2005年   59篇
  2004年   57篇
  2003年   49篇
  2002年   48篇
  2001年   17篇
  2000年   13篇
  1999年   30篇
  1998年   8篇
  1997年   10篇
  1996年   13篇
  1995年   4篇
  1994年   11篇
  1993年   8篇
  1992年   10篇
  1991年   14篇
  1990年   14篇
  1989年   14篇
  1988年   7篇
  1987年   14篇
  1986年   8篇
  1985年   7篇
  1984年   6篇
  1983年   9篇
  1982年   6篇
  1981年   5篇
  1976年   3篇
  1975年   4篇
  1974年   3篇
  1973年   4篇
  1966年   7篇
  1965年   3篇
  1926年   2篇
排序方式: 共有1202条查询结果,搜索用时 15 毫秒
31.
Homozygous or compound heterozygous mutations in the GJC2 gene, encoding the gap junction protein connexin47 (Cx47), cause the autosomal recessive hypomyelinating Pelizaeus–Merzbacher-like disease (PMLD1, MIM# 608804). Although clinical and neuroradiological findings resemble those of the classic Pelizaeus–Merzbacher disease, PMLD patients usually show a greater level of cognitive and motor functions. Unpredictably a homozygous missense GJC2 mutation (p.Glu260Lys) was found in a patient presenting with a very severe clinical picture characterised by congenital nystagmus and severe neurological impairment. Also magnetic resonance imaging was unusually severe, showing an abnormal supra- and infratentorial white matter involvement extending to the spinal cord. The novel p.Glu260Lys (c.778G>A) mutation, occurring in a highly conserved motif (SRPTEK) of the Cx47 extracellular loop-2 domain, was predicted, by modelling analysis, to break a ‘salt bridge network'', crucial for a proper connexin–connexin interaction to form a connexon, thus hampering the correct formation of the connexon pore. The same structural analysis, extended to the previously reported missense mutations, predicted that most changes were expected to have less severe impact on protein functions, correlating with the mild PMLD1 form of the patients. Our study expands the spectrum of PMLD1 and provides evidence that the extremely severe clinical and neuroradiological PMLD1 form of our patient likely correlates with the predicted impairment of gap junction channel assembly resulting from the detrimental effect of the new p.Glu260Lys mutant allele on Cx47 protein.  相似文献   
32.
ObjectiveTo compare the performance, reliability, and validity of functional tests between women with and without patellofemoral pain.MethodsTwenty women with a diagnosis of patellofemoral pain between 18 and 40 years of age and 20 age-matched pain-free controls participated in the study. All participants performed a set of five function tests: sitting-rising test, sit-to-stand in 30 seconds, stair-climb test, stair descent test, and six-minute step test. To investigate reliability, participants were assessed on two different days, seven days apart, by two independent investigators blinded to the results of the other investigator. Validity was evaluated through associations with the results on the Anterior Knee Pain Scale.ResultsPerformance in the tests was worse in women with patellofemoral pain than in the control group for the sit-to-stand in 30 seconds (mean difference [MD] 3.4reps; 95%CI: 0.4, 6.4), stair-climb test (MD: 0.36 s; 95%CI: 0.1, 0.63), and six-minute step test (MD: 45reps; 95%CI: 20, 70). No differences were observed for the sitting-rising and stair descent tests. All tests in both groups showed moderate to excellent intra- and inter-rater reliability (intraclass correlation coefficients: 0.61 to 0.91 and 0.72 to 0.96, respectively). Finally, only the results on the sit-to-stand in 30 seconds test correlated with the Anterior Knee Pain Scale (r = 0.44, p = 0.047) in the patellofemoral pain group.ConclusionWomen with patellofemoral pain present lower performance on some functional tests. Functional tests are reliable in patients with patellofemoral pain, although they are not associated with the results on the Anterior Knee Pain Scale self-questionnaire.  相似文献   
33.
34.
35.
36.
BACKGROUND: Treatment of patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) is problematic if diagnostic imaging is not immediately available. Pretest clinical probability (PCP) and D-dimer assessment can be used to identify patients for whom empirical protective anticoagulation is indicated. To evaluate whether PCP and D-dimer assessment, together with the use of low-molecular-weight heparins (LMWHs), allow objective appraisal of DVT and PE to be deferred for up to 72 hours, patients with suspected DVT and PE were prospectively examined. METHODS: Patients identified with a high PCP or a moderate PCP with positive D-dimer test results received a protective full-dose treatment of LMWH; the remaining patients were discharged without anticoagulant administration. However, all patients were scheduled to undergo objective tests for DVT or PE within 72 hours. Standard antithrombotic therapy was administered when deferred diagnostic tests confirmed venous thromboembolism. RESULTS: In total, 409 consecutive patients with suspected DVT and 124 with suspected PE were included in this study. A total of 23.8% (95% confidence interval [CI], 20.3%-27.3%) of patients had confirmed venous thromboembolism. At the short-term follow-up (72 hours), only a single thromboembolic event (0.2%; upper 95% CI, 0.6%) had occurred, whereas at the 3-month follow-up, 5 events (1.2%; 95% CI, 0.2%-2.1%) had occurred in patients in whom diagnosis of DVT or PE had previously been ruled out. None of the patients had major bleeding events. Ninety percent of patients were treated as outpatients. CONCLUSION: Our study demonstrates that this approach allows the safe deferral of diagnostic procedures for DVT and PE for up to 72 hours.  相似文献   
37.
In this paper, a new strategy for highly selective and sensitive direct detection of lymphoma cells by exploiting the interaction between a peptide and its B-cell receptor, has been evaluated. In particular, an idiotype peptide, able to specifically bind the B-cell receptor of A20 cells in mice engrafted with A20 lymphoma, has been used as molecular probe. The new detection technique has been demonstrated on a planar crystalline silicon chip. Coverage of 85% of silicon surface and detection efficiency of 8.5 × 10−3 cells/μm2 were obtained. The recognition strategy promises to extend its application in studying the interaction between ligands and their cell-surface receptors.OCIS codes: (000.1430) Biology and medicine, (280.1415) Biological sensing and sensors  相似文献   
38.
39.
Breast cancer is one of the most common tumors in the population worldwide. Conservative breast surgery (CBS) is one of the preferred surgical options, because both the oncologic and esthetic needs of the patient can be addressed. CBS surgical outcomes tend to be more effective with reduced chances of disease recurrence when radiotherapy (RT) treatment is considered as an adjunct treatment, either applied during surgery (IORT) and/or after (EBRT). The purpose of our study was to compare surgical outcomes between IORT and EBRT after CBS. In the past 5 years, we performed CBS in 489 patients in our clinic. Of these patients, 83 underwent adjunct treatment with IORT and 109 were treated with EBRT in accordance with our university approved clinical protocol. Surgical outcomes, early complication rates, and esthetic results were compared between these two groups of CBS patients, with a mean follow‐up time of 17 months. IORT allowed breast irradiation treatment to be performed without effecting overlying skin, thus cosmetic outcomes tended to be favorable. Esthetic postoperative results assessed with the Breast Cancer Conservation Treatment (BCCTcore) software showed that the differences between IORT and EBRT were not statistically significant (including those patients that underwent further oncoplastic techniques after EBRT). The disease recurrence rates between the two groups were not significantly different. IORT is a safe, fast, and feasible technique that provides effective and comparable CBS outcomes for patients with breast cancer.  相似文献   
40.
Robotic and Laparoscopic Surgery for Treatment of Colorectal Diseases   总被引:8,自引:0,他引:8  
PURPOSE In the last ten years, several robotic systems have been developed to overcome the loss of the three-dimensional view and dexterity characteristic of laparoscopic surgery. The aim of this study was to compare the traditional laparoscopic approach and robotic techniques in the treatment of colorectal diseases.METHODS The study compares a consecutive series of patients treated surgically for colorectal disease from June 2001 to May 2003 with the da Vinci robotic system (Intuitive Surgical®) and a matched number of patients who underwent conventional laparoscopy during the same time interval. The factors analyzed were the time required to prepare the patient and the room, total time of surgery, length of specimens, number of lymph nodes retrieved, blood loss, complications, and postoperative results.RESULTS The study included 106 patients (53 in each group). No differences were observed in total time of surgery (laparoscopic group, 222 ± 77 minutes vs. robotic group, 240 ± 61 minutes), specimen length (laparoscopic group, 29 ± 11 cm vs. robotic group, 27 ± 13 cm), or number of lymph nodes retrieved (laparoscopic group, 16 ± 9 vs. robotic group, 17 ± 10). It took significantly longer to prepare the operating room and patient in the robotic group (24 ± 12 minutes) than in the laparoscopic group (18 ± 7 minutes). There were three conversions to laparotomy in the laparoscopic group; in the robotic group, two cases were converted to laparoscopy and three to hand-assisted laparoscopy. No significant differences were observed between the two groups in terms of recovery of bowel function and postoperative hospital stay.CONCLUSIONS Robot-assisted surgery proved to be as safe and effective as laparoscopic techniques in the treatment of colorectal diseases. Because of its dexterity and three-dimensional view, the da Vinci system was particularly useful in specific stages of the procedure, e.g., takedown of the splenic flexure, dissection of a narrow pelvis, identification of nervous plexus, and handsewn anastomosis. The cost-effectiveness of the procedure still needs to be evaluated.  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