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   3041篇
  免费   192篇
  国内免费   10篇
耳鼻咽喉   16篇
儿科学   81篇
妇产科学   56篇
基础医学   327篇
口腔科学   31篇
临床医学   393篇
内科学   464篇
皮肤病学   40篇
神经病学   366篇
特种医学   119篇
外科学   444篇
综合类   22篇
一般理论   1篇
预防医学   306篇
眼科学   118篇
药学   243篇
  1篇
肿瘤学   215篇
  2023年   15篇
  2022年   55篇
  2021年   101篇
  2020年   57篇
  2019年   97篇
  2018年   125篇
  2017年   78篇
  2016年   75篇
  2015年   78篇
  2014年   119篇
  2013年   201篇
  2012年   240篇
  2011年   262篇
  2010年   163篇
  2009年   139篇
  2008年   210篇
  2007年   197篇
  2006年   192篇
  2005年   160篇
  2004年   156篇
  2003年   149篇
  2002年   127篇
  2001年   24篇
  2000年   14篇
  1999年   16篇
  1998年   14篇
  1997年   13篇
  1996年   10篇
  1995年   12篇
  1994年   20篇
  1993年   7篇
  1992年   11篇
  1991年   8篇
  1990年   8篇
  1989年   6篇
  1988年   6篇
  1987年   7篇
  1986年   9篇
  1985年   4篇
  1984年   6篇
  1983年   4篇
  1980年   3篇
  1979年   3篇
  1977年   3篇
  1973年   3篇
  1969年   4篇
  1968年   2篇
  1967年   5篇
  1966年   2篇
  1934年   2篇
排序方式: 共有3243条查询结果,搜索用时 15 毫秒
61.
ContextMentoring has been identified as an important method of supporting newly credentialed athletic trainers (ATs) during their transition to practice. Gaining a better understanding of this relationship could provide valuable insights that may assist employers and professional programs in developing a plan to better facilitate the transition.ObjectiveTo examine which aspects of the mentoring relationship provided the most benefit during the transition to practice of newly certified ATs.DesignQualitative study.SettingIndividual phone interviews.Patients or Other ParticipantsA total of 13 ATs who graduated from a professional master''s program, were certified from February through July 2016, and obtained employment from July through August 2016 participated in this study (6 women, 7 men; age = 26 ± 3 years; work settings included professional sports, college, secondary and middle school, and clinic). Data saturation guided the number of participants.Data Collection and AnalysisPhone interviews using a semistructured interview guide were conducted at 3, 8, and 12 months of work experience. Data were analyzed using a constant comparative approach. Credibility was established via investigator triangulation, peer debriefing, and member checks.ResultsParticipants recognized the mentoring relationship as a foundational aspect of the transition to practice. Mentors should be available by phone, email, or text to answer questions, provide feedback, or discuss ideas. Respondents wanted honest feedback, even when that feedback was constructively critical. Feedback was sought regarding topics such as patient care, communication, and networking. Participants needed reassurance and support from their mentors to help validate and improve their self-confidence.ConclusionsNewly credentialed ATs should seek mentors who will be available to communicate in various ways and will provide regular and constructive feedback. Future researchers should investigate how mentoring relationships influence other aspects of the transition to practice, such as patient care, overall job performance, turnover, and satisfaction.  相似文献   
62.
63.
Objective:To assess accuracy of and interobserver agreement on multiparametric MR findings to distinguish uterine leiomyoma (LM) from uterine leiomyosarcoma (LMS) and soft tissue tumour of unknown malignant potential.Methods:Inclusion criteria: All females over 18 years with least one uterine mass measuring 5 cm or more in at least one of the three standard orthogonal dimensions on MR with histopathological confirmation of LM, LMS, or soft tissue tumour of unknown malignant potential (STUMP) in the 3 months following MR. Patients with LMS were drawn from a larger cohort being assessed for MR-guided focussed ultrasound (MRgFUS) suitability. Image evaluation: Assessed variables were: lesion margin, margin definition, T2 signal homogeneity, >50% of lesion with T2 signal brighter than myometrium, haemorrhage, restricted diffusion, contrast enhancement (CE), CE pattern, local lymphadenopathy and ascites.Results:32 LM, 10 LMS and 1 STUMP were evaluated. Ill-defined (p-value = 0.0003–0.0004) or irregular (p = 0.003–0.004) lesion margin, T2 hyperintensity >50% (p = 0.001–0.004), and peripheral CE (p = 0.02–0.05) were significantly more common in LMS/STUMP than LM for both radiologists. 10/11 (Reader 2) and 11/11 (Reader 1) LMS/STUMP displayed restricted diffusion but so did 63–80% of LM. Agreement was greatest for margin characteristics (κ = 0.73–0.81).Conclusion:Irregular/ill-defined lesion margin best distinguished LMS/STUMP from LM with good interrater reliability.Advances in knowledge:Assessment of agreement regarding MR parameters distinguishing LM from LMS and STUMP has not previously been undertaken in a cohort including a large number of patients with LMS. This will help inform evaluation of females considering minimally invasive LM treatment.  相似文献   
64.
65.
66.
The objective of this study was to elucidate gene and protein expression of Wnt signaling molecules in chondrocytes of foals having early osteochondrosis (OC) versus normal controls. The hypothesis was that increased expression of components of Wnt signaling pathway in osteochondral junction (OCJ) and cartilage canal (CC) chondrocytes would be found in early OC when compared to controls. Paraffin‐embedded osteochondral samples (7 OC, 8 normal) and cDNA from whole cartilage (7 OC, 10 normal) and chondrocytes surrounding cartilage canals and osteochondral junctions captured with laser capture microdissection (4 OC, 6 normal) were obtained from femoropatellar joints of 17 immature horses. Equine‐specific Wnt signaling molecule mRNA expression levels were evaluated by two‐step real‐time qPCR. Spatial tissue protein expression of β‐catenin, Wnt‐11, Wnt‐4, and Dkk‐1 was determined by immunohistochemistry. There was significantly decreased Wnt‐11 and increased β‐catenin, Wnt‐5b, Dkk‐1, Lrp6, Wif‐1, Axin1, and SC‐PEP gene expression in early OC cartilage canal chondrocytes compared to controls. There was also significantly increased β‐catenin gene expression in early OC osteochondral junction chondrocytes compared to controls. Based on this study, abundant gene expression differences in OC chondrocytes surrounding cartilage canals suggest pathways associated with catabolism and inhibition of chondrocyte maturation are targeted in early OC pathogenesis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1433–1438, 2015.  相似文献   
67.
Patients with polycythemia vera and essential thrombocythemia are at risk for thrombotic and bleeding complications. Currently, no diagnostic test can predict thrombohemorrhagic complications. In a prospective study of 86 patients with polycythemia vera (43 patients) or essential thrombocythemia (43 patients), we examined the possible role of polymorphisms of platelet adhesion receptors [glycoprotein (GP) Ibalpha, GPIa, GPIIIa) and clotting factor II (prothrombin's G20210A mutation) and clotting factor V (Leiden mutation) in determining the risk of thrombotic or bleeding complications. Except for an association between vasomotor symptoms and prothrombin mutation (P < 0.001), no significant correlation between polymorphism of clotting factors and thrombohemorrhagic complications was identified. When the entire patient cohort was considered, the polymorphisms of platelet adhesion receptors were not associated with the risk for thrombotic or bleeding complications. However, among patients with polycythemia vera, the presence of the PlA2 allele of GPIIIa was associated with an increased risk of arterial thrombosis. In view of previous studies linking the presence of the PlA2 allele of GPIIIa to a higher risk for coronary artery thrombosis, our data have physiologic relevance. However, they need to be confirmed in a larger study.  相似文献   
68.
We report a case of a woman with recurrent axillary fungating breast cancer who developed catastrophic hemorrhage from tumor erosion of her axillary artery. This was treated successfully with endovascular placement of a covered arterial stent. We discuss the suitability of endovascular therapy for patients with advanced malignancy given its lower morbidity in this population with decreased life expectancy.  相似文献   
69.
70.
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