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   1048669篇
  免费   72341篇
  国内免费   2853篇
耳鼻咽喉   14528篇
儿科学   33283篇
妇产科学   29371篇
基础医学   146872篇
口腔科学   31363篇
临床医学   85878篇
内科学   215862篇
皮肤病学   22946篇
神经病学   83933篇
特种医学   41382篇
外国民族医学   360篇
外科学   160584篇
综合类   20336篇
现状与发展   2篇
一般理论   309篇
预防医学   80133篇
眼科学   23149篇
药学   73352篇
中国医学   2538篇
肿瘤学   57682篇
  2021年   9368篇
  2019年   9585篇
  2018年   13533篇
  2017年   10449篇
  2016年   10918篇
  2015年   12610篇
  2014年   17720篇
  2013年   25693篇
  2012年   35783篇
  2011年   37795篇
  2010年   22063篇
  2009年   20630篇
  2008年   34011篇
  2007年   36145篇
  2006年   35583篇
  2005年   35385篇
  2004年   33727篇
  2003年   32241篇
  2002年   30098篇
  2001年   45029篇
  2000年   46151篇
  1999年   39478篇
  1998年   11243篇
  1997年   10168篇
  1996年   10106篇
  1995年   9315篇
  1994年   8935篇
  1993年   8398篇
  1992年   30155篇
  1991年   28909篇
  1990年   28179篇
  1989年   27135篇
  1988年   25162篇
  1987年   24638篇
  1986年   23677篇
  1985年   22480篇
  1984年   16776篇
  1983年   14272篇
  1982年   8531篇
  1979年   15329篇
  1978年   10674篇
  1977年   9022篇
  1976年   8478篇
  1975年   9421篇
  1974年   11144篇
  1973年   10618篇
  1972年   10045篇
  1971年   9268篇
  1970年   8982篇
  1969年   8380篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
92.
93.
94.
Thyroid diseases are common, and use of levothyroxine is increasing worldwide. We investigated the influence of gender, race and socioeconomic status on the diagnosis and treatment of thyroid disorders using data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), a multicenter cohort study of civil servants (35-74 years of age) from six Brazilian cities. Diagnosis of thyroid dysfunction was by thyrotropin (TSH), and free thyroxine (FT4) if TSH was altered, and the use of specific medications. Multivariate logistic regression models were constructed using overt hyperthyroidism/hypothyroidism and levothyroxine use as dependent variables and sociodemographic characteristics as independent variables. The frequencies of overt hyper- and hypothyroidism were 0.7 and 7.4%, respectively. Using whites as the reference ethnicity, brown, and black race were protective for overt hypothyroidism (OR=0.76, 95%CI=0.64-0.89, and OR=0.53, 95%CI=0.43-0.67, respectively, and black race was associated with overt hyperthyroidism (OR=1.82, 95%CI=1.06-3.11). Frequency of hypothyroidism treatment was higher in women, browns, highly educated participants and those with high net family incomes. After multivariate adjustment, levothyroxine use was associated with female gender (OR=6.06, 95%CI=3.19-11.49) and high net family income (OR=3.23, 95%CI=1.02-10.23). Frequency of hyperthyroidism treatment was higher in older than in younger individuals. Sociodemographic factors strongly influenced the diagnosis and treatment of thyroid disorders, including the use of levothyroxine.  相似文献   
95.
96.
97.
Psoriasis is a chronic, inflammatory, immune‐mediated disease. Approximately 30% of patients have disease onset before age 18 years. Psoriasis in children and adolescents may be difficult to control, with subsequent poor quality of life and psychosocial consequences. We describe the case of a 12‐year‐old boy with severe, refractory, chronic plaque psoriasis for 6 years. Various therapeutic regimens including different topical corticosteroids, topical vitamin D analogs, phototherapy, photochemotherapy, systemic therapy with methotrexate, cyclosporin, and combination therapies showed only partial or transient responses with frequent relapses. Because anti‐interleukin‐12/23 agents have been successfully used in adults with psoriasis, ustekinumab was initiated and our patient showed a rapid, excellent, sustained response. No recurrence or flares have been observed after 33 months of follow‐up. This case illustrates that ustekinumab may be an effective and safe therapeutic option in adolescents with psoriasis.  相似文献   
98.
We report a case of intestinal obstruction in a 73-year-old woman caused by ileocolic intussusception. The underlying cause was a giant submucosal ulcerating lipoma (6?×?3.3?×?3.8 cm) extending from the superior mucosal lip of Bauhin’s valve. Abdominal ultrasonography showed a pathognomonic target-like mass appearing as multiple concentric rings. CT scan confirmed the diagnosis. Because of apparent obstruction, a laparotomy with right hemicolectomy and ileocolic anastomosis was performed. Lipomas most frequently occur in the cecum and ascending colon where they represent the most common submucosal mesenchymal tumor. They typically occur in elderly women with an incidence that varies from 0.15 to 0.56 %. Pain, rectal bleeding, and obstruction are typical symptoms. When faced with an intussusception in children, reduction with air per rectum can be performed. In adults, however, malignant cell spreading and seeding is of big concern. Since approximately 20–50 % of all underlying causes are malignant, explorative surgery is favored in adults.  相似文献   
99.
100.
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