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   1712篇
  免费   128篇
  国内免费   9篇
耳鼻咽喉   1篇
儿科学   44篇
妇产科学   43篇
基础医学   241篇
口腔科学   25篇
临床医学   119篇
内科学   444篇
皮肤病学   16篇
神经病学   127篇
特种医学   36篇
外科学   199篇
综合类   14篇
一般理论   1篇
预防医学   193篇
眼科学   30篇
药学   137篇
中国医学   5篇
肿瘤学   174篇
  2023年   13篇
  2022年   27篇
  2021年   47篇
  2020年   26篇
  2019年   36篇
  2018年   32篇
  2017年   30篇
  2016年   37篇
  2015年   45篇
  2014年   56篇
  2013年   81篇
  2012年   109篇
  2011年   131篇
  2010年   74篇
  2009年   69篇
  2008年   108篇
  2007年   125篇
  2006年   116篇
  2005年   94篇
  2004年   120篇
  2003年   79篇
  2002年   80篇
  2001年   18篇
  2000年   18篇
  1999年   21篇
  1998年   22篇
  1997年   14篇
  1996年   14篇
  1995年   13篇
  1994年   12篇
  1993年   11篇
  1992年   17篇
  1991年   22篇
  1990年   17篇
  1989年   11篇
  1988年   18篇
  1987年   4篇
  1986年   9篇
  1985年   9篇
  1984年   13篇
  1983年   4篇
  1982年   10篇
  1981年   4篇
  1980年   6篇
  1979年   4篇
  1978年   2篇
  1977年   4篇
  1976年   3篇
  1974年   2篇
  1973年   3篇
排序方式: 共有1849条查询结果,搜索用时 31 毫秒
1.
2.
Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy; a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands.  相似文献   
3.
This report is a retrospective clinical randomized study carried out on 114 cases of incidental prostatic carcinoma aged 55-87 years, 58 untreated and 56 treated with cyproterone acetate (CPA 200 mg/day) for 6 months, immediately after surgery. 78 cases were staged A1 and the remaining 36 A2. In stage A1, 75 cases were histologically graded G1, and 3 G2, whereas in stage A2, 7 cases were G1, 19 G2 and 10 G3. Moreover, flow cytometric DNA analysis showed in A1 20 G1 carcinomas with nuclear diploidy and 3 G2 with nuclear aneuploidy, in stage A2, 4 G3 tumors with nuclear aneuploidy. During the 4-year follow-up, 25/28 patients of the untreated group and 15/56 of the CPA-treated group were found in progression. In A1, progression was found in 6/37 untreated patients and 5/41 CPA-treated, whilst in A2 progression was observed in 19/21 untreated patients and in 10/15 treated with CPA. The critical period for progression was between the 2nd and 3rd year of follow-up. In A1, therefore, 6 months of therapy with CPA does not modify the progression rate, which is significantly improved in A2 (66% in the treated and 90% in the untreated group) during the first 30 months of follow-up. The prognosis may probably be further improved by continuing endocrine therapy.  相似文献   
4.
To assess the magnitude and nature of interpersonal violence resulting in hospitalisation of children and to identify subgroups at risk of repeat hospital admissions, a population-based, retrospective study of all violence hospitalisations in Western Australia for children aged 9 years or less was undertaken, using the 1990–2004 linked data retrieved from the Western Australian Mortality Database and the Hospital Morbidity Data System.
Of the 747 patients aged <10 years incurring 834 hospitalisations for the consequences of violence during the study period, 570 (76%) were less than 4 years of age. A total of 43 deaths from violence were recorded and 74 (9%) patients were admitted for more than one episode of violence. Victims aged 0–4 years from rural (hazard ratio [HR] = 2.72; 95% confidence interval [CI] 1.35, 5.43) and remote parts (HR = 2.79; 95% CI 1.25, 6.25) of the state were at increased risk of a subsequent admission for violence compared with those residing within the metropolitan area. Indigenous children aged 5–9 years were significantly more likely (HR = 3.57; 95% CI 1.14, 11.13) to incur a second hospitalisation for violence than their non-Indigenous counterparts. The identification of young victim subgroups at high risk of repeat hospitalisations is important for developing intervention strategies to reduce the burden of interpersonal violence. Young children aged 0–4 years living in rural and remote locations and Indigenous children aged 5–9 years should be specifically targeted for attention.  相似文献   
5.
A child had the characteristic clinical and EEG pattern of migrating partial seizures in infancy with left temporal lobe atrophy, hippocampal sclerosis and cortical-subcortical blurring.Seizures were drug-resistant, with recurring episodes of status epilepticus. The child developed microcephaly with arrest of psychomotor development. Focal brain lesions, in the context of migrating partial seizures, have not been previously reported.[Published with video sequences].  相似文献   
6.
Distributional Issues in the Analysis of Preventable Hospitalizations   总被引:1,自引:0,他引:1  
  相似文献   
7.
The aim of this study was to analyze the characteristics of 17 women with renal-cell carcinoma (RCC) associated with other primary neoplasms occurring in steroid-hormone target tissues. The reproductive history of these patients and the use of exogenous hormones were taken into consideration. In all, 10 RCCs were associated with breast carcinoma; 4, with endometrial carcinoma; and 3, with ovarian carcinoma. The presentation of a second primary tumor was described as synchronous or metachronous by evaluation of the interval between the discovery of the two neoplasms. Hormone and surgical treatment as well as pathologic findings for each primary tumor were also reported. In these 17 RCCs the overall rate of disease-specific survival recorded after a mean follow-up period of 32.7 months (range 9–66 months) was 58.8%; 7 patients died of metastatic disease after surviving for a mean of 14.7 months. In terms of the pathologic stage of RCC, a significant difference in mean survival was found between pN0 (mean survival 22.1 ± 3.4 months) and pN 1 RCCs (mean survival 13.7 ± 3.5 months). A total of 13 (76.4%) women were postmenopausal at the time of diagnosis of the first primary tumor; the mean age of these women at menopause was 51.7 ± 1.2 years. No prior use of oral contraceptives was reported by 12 (70.5%) of the 17 patients. Plasma 17-beta-estradiol and estrone levels were determined in only 7 patients at the diagnosis of each of the primary tumors. High plasma estrogen levels were found in 4 women with RCC and breast carcinoma and in 1 patient with RCC and endometrial carcinoma; in the remaining 2 patients low-normal values were found. A relationship appears to exist between certain reproductive and hormone-related factors and the risk of developing these tumor associations. Data emerging from the present study do not provide strong support for the hypothesis of hormone dependency of RCC; however, a role for estrogens in cases in which RCC is associated with other primary tumors involving steroid-hormone target tissues can be hypothesized.  相似文献   
8.
Eating disorders have generally been considered uncommon among ethnic minorities. However, there are data that suggest bulimia nervosa may not be all that rare in some minority groups. Furthermore, emerging data on binge eating disorder (BED) have indicated high rates in some ethnic groups, and these data prompt reconsideration of the view that minority populations are protected from eating disorders. The current report reviews data on bulimia nervosa and BED in ethnic minority groups. Ramifications of a broader diversity of affected individuals on our understanding of eating disorders will be addressed, and directions for further research will be discussed.  相似文献   
9.
目的:在接受冠状动脉搭桥术(CABG)的患者中研究无症状性颈部血管杂音对检测颈内动脉疾病的预测价值。设计:一项前瞻性队列研究。背景:三级转诊大学医院。患者:连续153例施行CABG的患者,平均年龄57岁,既往无脑血管病史。干预措施:患者行详细的术前检查,包括冠状动脉造影和颈动脉  相似文献   
10.
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