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   2645篇
  免费   113篇
  国内免费   21篇
耳鼻咽喉   115篇
儿科学   71篇
妇产科学   208篇
基础医学   179篇
口腔科学   131篇
临床医学   199篇
内科学   530篇
皮肤病学   46篇
神经病学   152篇
特种医学   141篇
外科学   567篇
综合类   22篇
预防医学   49篇
眼科学   158篇
药学   76篇
中国医学   3篇
肿瘤学   132篇
  2024年   2篇
  2023年   19篇
  2022年   26篇
  2021年   67篇
  2020年   39篇
  2019年   79篇
  2018年   69篇
  2017年   53篇
  2016年   81篇
  2015年   90篇
  2014年   117篇
  2013年   137篇
  2012年   184篇
  2011年   186篇
  2010年   152篇
  2009年   113篇
  2008年   183篇
  2007年   209篇
  2006年   183篇
  2005年   187篇
  2004年   166篇
  2003年   141篇
  2002年   107篇
  2001年   34篇
  2000年   23篇
  1999年   15篇
  1998年   12篇
  1997年   15篇
  1996年   7篇
  1995年   3篇
  1994年   5篇
  1992年   6篇
  1991年   3篇
  1990年   4篇
  1989年   9篇
  1988年   3篇
  1987年   8篇
  1986年   3篇
  1985年   5篇
  1983年   4篇
  1980年   2篇
  1979年   2篇
  1978年   2篇
  1974年   4篇
  1970年   3篇
  1969年   3篇
  1968年   2篇
  1967年   5篇
  1966年   2篇
  1965年   3篇
排序方式: 共有2779条查询结果,搜索用时 0 毫秒
51.
52.
BACKGROUND: Up to date, three thyroid-stimulating hormone receptor (TSHR) germline variants have been reported for which no functional consequences have been detected by in vitro characterizations. However, familial nonautoimmune hyperthyroidism and hot nodules are clearly associated with constitutively activating TSHR germline mutations. We describe a family with a new TSHR germline mutation that is associated with euthyroidism in 13 family members and hyperthyroidism in 1 family member. METHODS: Mutation analysis of the TSHR gene was performed by denaturing gradient gel electrophoresis. TSHR constructs were characterized by determination of cell surface expression, 3'-5'-cyclic adenosine monophosphate (cAMP) accumulation, and constitutive cAMP activity. RESULTS: A novel TSHR germline mutation (N372T) was found in a man who presented with thyrotoxicosis. The mutation was also detected in 13 family members, all of whom were euthyroid. Interestingly, an additional constitutively active somatic mutation (S281N) was identified on the second parental TSHR allele of the hyperthyroid index patient. Linear regression analysis showed a lack of constitutive activity for N372T. Moreover, coexpression studies of N372T with S281N did not reveal any evidence for a functional influence of N372T on the constitutively active mutation (CAM). CONCLUSIONS: N372T is unlikely to cause altered thyroid function. This is consistent with the finding that only the index patient with the additional somatic mutation S281N was hyperthyroid.  相似文献   
53.
Bladder urothelial carcinoma is rare in young adults and occurs more commonly in older individuals. The aim of this study was to compare the clinical behavior, pathologic characteristics, and prognosis of urothelial carcinoma of urinary bladder in young versus older adults. A retrospective review of our records between 2007 and 2013 identified 56 patients (42 males and 14 females) with transitional cell carcinoma of the bladder who were less than 40 years old. Clinical and pathological parameters of patients who were less than 40 years of age were compared with those of a series of patients older than 40 years of age (the control group) during the same period. A survival analysis was performed using the Kaplan–Meier method and log-rank test, and Cox regression was performed to identify clinical parameters that affected the clinical outcomes. The mean age was 29.21 years (range, 5–40 years) for patients less than 40 years old and 61.66 years (range, 41–75) for those older than 40 years. The mean follow-up was 40.26 months (range, 12–65 months) for young patients and 42.57 months (range, 12–72 months) for the older patients. Young bladder cancer patients had smaller-sized tumors (less than 3 cm), less high-grade cancers, higher papillary urothelial neoplasms of low malignant potential, and low-grade tumors than patients older than 40 years. Multivariate logistic regression analysis predicted tumor recurrence in young patients with high-grade tumors [odds ratio (OR), 1.959; 95% confidence interval (CI), 1.235–2.965; p = 0.046] and tumors larger than 3 cm (OR, 1.772; 95% CI, 1.416–1.942; p = 0.032). The 5-year overall survival rate was 100% for young patients and 88.1% for older patients. No difference was observed in the recurrence-free (p = 0.321) and progression-free (p = 0.422) survival rates between the two groups. We concluded that although the clinical stage distribution, natural history, and outcomes of bladder urothelial cancer in young adults are similar to those in their older counterparts, clinicians must be aware that patients under 40 years of age presented with higher-grade and larger (>3 cm) tumors and are more likely to experience tumor recurrence.  相似文献   
54.
Isolated atrial septal defect (ASD) is the most common form of congenital heart abnormalities in adults and approximately 80% are located in the region of the fossa ovalis (ostium secundum ASD).1 Indications for closure are in cases where the ratio of pulmonary-to-systemic flow (Qp/Qs) is higher than 1.5, without significant elevation of pulmonary vascular resistance.Surgical closure of ASDs has been performed for over 60 years and techniques have steadily improved, using smaller incisions and minimally invasive techniques. On the other hand, in the last 20 years, various transcatheter ASD closure techniques and devices have been developed, among which, percutaneous treatment with a septal occluder device is the most popular.2,3Despite increasing use of occluder devices and the fact that studies have been published internationally pointing out some of the advantages and disadvantages compared with surgery in adults, no formal comparison of efficacy, morbidity and complications has been published.2-4 We present a retrospective comparison of short-term (three months) results for transcatheter and surgical closure of 163 ostium secundum ASD patients in a university hospital.  相似文献   
55.
The FES-I is a questionnaire which was developed to assess fear of falling. The aim of this study was to evaluate validity and reliability of a Turkish language version of the FES-I in Turkish older people. The study sample included 70 volunteers with an age range of 65-81. To assess the test-retest reliability of the Turkish FES-I, questionnaire was applied again 10-15 days after the first interview (interclass correlation: ICC). FES-I was compared with The Modified Barthel Index (MBI), the timed up and go test (TUG), and The Berg Balance Scale (BBS) for construct validity. Cronbach's alpha (α) was used to evaluate the internal consistency. The internal structure of the FES-I was examined by factor analysis. ROC plots were used to define cut-point for the FES-I scales. Cronbach's α of the Turkish FES-I was 0.94 and the individual item ICC ranged from 0.97 to 0.99. The Turkish FES-I total scores were correlated with TUG positively, and MBI, and BBS negatively. The cut-off score to differentiate between persons with fear of falling and persons without fear of falling was 24 points. It was found that the Turkish version of the FES-I was a reliable and valid measure of fear of falling in Turkish older people.  相似文献   
56.
57.
58.
59.
60.
Diabetic muscular infarct (DMI) is a rare condition, which begins with acute onset of extremity pain and swelling. Patients usually have long-standing disease and poorly controlled diabetes mellitus (DM). Thigh muscle group is the most commonly involved side, while lower leg involvement is rare. We represent herein a 22-year-old patient with type I DM who admitted to our outpatient clinic due to painful swelling of the left leg. In physical examination, anterior left leg was painful and firm on palpation; there was diffuse swelling extending to the knee and ankle with mild local fever and redness. T2-weighted MRI demonstrated hyperintensity in left leg muscles. A biopsy confirmed the diagnosis of DMI. She was treated with glucose regulation, analgesics, antiplatelet treatment and rest. At her 6 months, recurrence of DMI was observed. DMI should be considered in diabetic patients with extremity pain and swelling. Treatment plan should include the regulation of the blood glucose and evaluation of end-organ complications, analgesia, and bed rest.  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