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   1337642篇
  免费   114779篇
  国内免费   6364篇
耳鼻咽喉   16709篇
儿科学   43031篇
妇产科学   36675篇
基础医学   183763篇
口腔科学   36287篇
临床医学   120825篇
内科学   278787篇
皮肤病学   31898篇
神经病学   110668篇
特种医学   55605篇
外国民族医学   274篇
外科学   210459篇
综合类   31572篇
现状与发展   2篇
一般理论   415篇
预防医学   106770篇
眼科学   28097篇
药学   93816篇
  5篇
中国医学   2227篇
肿瘤学   70900篇
  2018年   13379篇
  2017年   10645篇
  2016年   12813篇
  2015年   14315篇
  2014年   19965篇
  2013年   29788篇
  2012年   36282篇
  2011年   38921篇
  2010年   24399篇
  2009年   23937篇
  2008年   36398篇
  2007年   38834篇
  2006年   39957篇
  2005年   38542篇
  2004年   36792篇
  2003年   35883篇
  2002年   33904篇
  2001年   66088篇
  2000年   67967篇
  1999年   56636篇
  1998年   16745篇
  1997年   15032篇
  1996年   16031篇
  1995年   16242篇
  1994年   15111篇
  1993年   14158篇
  1992年   47114篇
  1991年   45768篇
  1990年   43987篇
  1989年   41830篇
  1988年   38778篇
  1987年   38107篇
  1986年   35874篇
  1985年   34664篇
  1984年   26375篇
  1983年   22126篇
  1982年   13858篇
  1981年   12455篇
  1980年   11733篇
  1979年   23567篇
  1978年   17093篇
  1977年   14401篇
  1976年   13208篇
  1975年   13746篇
  1974年   16120篇
  1973年   15407篇
  1972年   14190篇
  1971年   13060篇
  1970年   11900篇
  1969年   11108篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.  相似文献   
93.
94.
95.
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   
96.
ABSTRACT

Objective

To investigate primary care physician clinical practice patterns, barriers, and education surrounding pediatric physical activity (PA), and to compare practice patterns by discipline.  相似文献   
97.
98.
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   
99.
Moderate weight loss improves numerous risk factors for cardiometabolic disease; however, long-term weight loss maintenance (WLM) is often thwarted by metabolic adaptations that suppress energy expenditure and facilitate weight regain. Skeletal muscle has a prominent role in energy homeostasis; therefore, we investigated the effect of WLM and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity-prone rats, WLM reduced fat oxidative capacity and downregulated genes involved in fat metabolism. Interestingly, even after weight was regained, genes involved in fat metabolism were also reduced. We then subjected mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, to WLM and weight regain and found that mCK-hLPL attenuates weight regain by potentiating energy expenditure. Irrespective of genotype, weight regain suppressed dietary fat oxidation and downregulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain. In summary, these results suggest that skeletal muscle fat oxidation is reduced during WLM and regain, and therapies that improve skeletal muscle fat metabolism may attenuate rapid weight regain.  相似文献   
100.
An association between juvenile xanthogranuloma (JXG), neurofibromatosis type 1 (NF1), and juvenile myelomonocytic leukemia (JMML) has been described in the literature but has only been documented in approximately 20 cases. We diagnosed a patient with NF1 at 25 months of age, before any cutaneous stigmata of this disease had appeared, because we decided to screen for the NF1 gene mutation because of his presentation with multiple JXGs and moderate macrocephaly (2.5 standard deviations) at 9 months of age and JMML diagnosed at 20 months of age. The child is well today after treatment with chemotherapy and allogenic bone marrow transplantation. With increased awareness, patients with JXG and NF1 who develop symptoms possibly related to JMML, such as paleness, skin bleeding, cough, unexplained fever, and hepatosplenomegaly, should be further evaluated. We also emphasize that multiple JXG lesions can be an early marker of NF1.  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