全文获取类型
收费全文 | 9002篇 |
免费 | 720篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 260篇 |
妇产科学 | 162篇 |
基础医学 | 926篇 |
口腔科学 | 188篇 |
临床医学 | 800篇 |
内科学 | 2001篇 |
皮肤病学 | 99篇 |
神经病学 | 721篇 |
特种医学 | 199篇 |
外科学 | 1492篇 |
综合类 | 98篇 |
一般理论 | 4篇 |
预防医学 | 971篇 |
眼科学 | 157篇 |
药学 | 580篇 |
中国医学 | 7篇 |
肿瘤学 | 1004篇 |
出版年
2023年 | 67篇 |
2022年 | 106篇 |
2021年 | 309篇 |
2020年 | 159篇 |
2019年 | 232篇 |
2018年 | 311篇 |
2017年 | 182篇 |
2016年 | 178篇 |
2015年 | 186篇 |
2014年 | 258篇 |
2013年 | 364篇 |
2012年 | 559篇 |
2011年 | 578篇 |
2010年 | 330篇 |
2009年 | 285篇 |
2008年 | 491篇 |
2007年 | 506篇 |
2006年 | 480篇 |
2005年 | 428篇 |
2004年 | 438篇 |
2003年 | 447篇 |
2002年 | 418篇 |
2001年 | 172篇 |
2000年 | 175篇 |
1999年 | 170篇 |
1998年 | 114篇 |
1997年 | 98篇 |
1996年 | 77篇 |
1995年 | 70篇 |
1994年 | 74篇 |
1993年 | 58篇 |
1992年 | 102篇 |
1991年 | 107篇 |
1990年 | 101篇 |
1989年 | 83篇 |
1988年 | 75篇 |
1987年 | 66篇 |
1986年 | 59篇 |
1985年 | 59篇 |
1984年 | 67篇 |
1983年 | 49篇 |
1982年 | 44篇 |
1981年 | 44篇 |
1980年 | 46篇 |
1979年 | 46篇 |
1978年 | 46篇 |
1977年 | 40篇 |
1976年 | 37篇 |
1972年 | 35篇 |
1971年 | 33篇 |
排序方式: 共有9745条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
K Pritchard-Jones A Kelsey G Vujanic J Imeson C Hutton C Mitchell 《Journal of clinical oncology》2003,21(17):3269-3275
PURPOSE: To identify clinical prognostic factors in children with stage I, favorable histology (FH) Wilms' tumor treated with vincristine monochemotherapy after immediate nephrectomy to define subgroups for consideration of further reduction in treatment intensity. PATIENTS AND METHODS: During two consecutive trials of the United Kingdom Children's Cancer Study Group (UKW2 and UKW3, 1986 to 2001), 242 children with stage I FH Wilms' tumor were treated with immediate nephrectomy followed by 10 weekly injections of vincristine 1.5 mg/m2. Event-free survival (EFS) and overall survival (OS) were compared by age group. RESULTS: The 4-year EFS rate was 93.2%, 87.2%, and 71.3% for children less than 2 years old, 2 to 4 years old, and 4 years old or older at diagnosis, respectively (log-rank, P =.001); the corresponding 4-year OS rate was 98.1%, 95.0%, and 87.2% (log-rank, P =.01). There were no toxicity- or procedure-related deaths. In multivariate analysis, specimen weight was not of independent prognostic value (P =.66). Among the 186 children younger than 4 years at diagnosis, there were 17 relapses and five deaths, compared with 16 relapses and eight deaths among the 56 children at least 4 years old at diagnosis. OS after relapse was surprisingly poor (61.6% at 4 years). CONCLUSION: Treatment for stage I FH Wilms' tumor is generally successful using vincristine monotherapy after immediate nephrectomy, and therefore, the risks of dactinomycin hepatopathy can be avoided. However, age at least 4 years is a significant adverse prognostic factor. This treatment schedule should be considered in any trial of treatment reduction in very young children with stage I FH Wilms' tumor, regardless of tumor size, and we suggest that the upper age limit for the reduced therapy be set at 4 years. 相似文献
5.
Background
In meningitis, the cerebrospinal fluid contains high levels of innate immune molecules (e.g. complement) which are essential to ward off the infectious challenge and to promote the infiltration of phagocytes (neutrophils, monocytes). However, epithelial cells of either the ependymal layer, one of the established niche for adult neural stem cells, or of the choroid plexus may be extremely vulnerable to bystander attack by cytotoxic and cytolytic complement components. 相似文献6.
7.
Erika E Forbes Douglas E Williamson Neal D Ryan Boris Birmaher David A Axelson Ronald E Dahl 《Neuropsychopharmacology》2006,59(1):24-30
BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation. 相似文献
8.
Jennifer B. Gray Neal D. Gray 《International journal of mental health and addiction》2006,4(4):307-318
Some researchers speculate that as many as 10% of users worldwide suffer from “problematic” use of the internet, possibly stemming from an internet dependency. Research is in its early stages, making it an uncertain issue for mental health professionals. This paper provides: (1) a critical review of research on problematic internet use for the mental health and addictions professional; and (2) practical implications, including suggestions on treatment and prevention, given its uncertain clinical classification. 相似文献
9.
10.
Agenesis of the Gallbladder Revisited Laparoscopically 总被引:1,自引:0,他引:1
Najam Azmat M.D. Kenneth R. Francis M.D. Neal Mandava M.D. Walter F. Pizzi M.D. 《The American journal of gastroenterology》1993,88(8):1269-1270
Gallbladder agenesis is an extremely rare disease. Necropsy incidence has been reported to be 0.016%. Failure lo locate the gallbladder at the time of a planned cholecystectomy can be very challenging. We report such a case during a laparoscopic cholecystectomy. The indication for surgery in these patients are complaints of gallbladder symptoms along with a false-positive ultrasound study. During exploration, an abnormal location of the gallbladder has to be excluded. Ectopic gallbladder locations include intrahepatic, lesser omentum, retroperitoneal, retrohepatic, within the falciform ligament, retroduodenal, and retrohepatic areas. Thorough exploration and cholangiography are essential. Embryologically, the gallbladder and cystic duct arise from the caudal portion of the hepatic bud. All of the previously reported cases of gallbladder agenesis have shown an absence of both the gallbladder and cystic duct. We report an embryological oddity wherein a patent cystic duct was found along with an agenetic gallbladder. This is the first case report of this finding, along with this being the first absent gallbladder discovered laparoscopically. 相似文献