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   1338篇
  免费   359篇
  国内免费   13篇
耳鼻咽喉   6篇
儿科学   18篇
妇产科学   45篇
基础医学   41篇
口腔科学   75篇
临床医学   206篇
内科学   418篇
皮肤病学   55篇
神经病学   241篇
特种医学   46篇
外科学   185篇
预防医学   149篇
眼科学   113篇
药学   16篇
肿瘤学   96篇
  2024年   4篇
  2023年   45篇
  2022年   10篇
  2021年   27篇
  2020年   60篇
  2019年   22篇
  2018年   90篇
  2017年   101篇
  2016年   99篇
  2015年   84篇
  2014年   113篇
  2013年   138篇
  2012年   50篇
  2011年   48篇
  2010年   87篇
  2009年   140篇
  2008年   47篇
  2007年   26篇
  2006年   38篇
  2005年   38篇
  2004年   16篇
  2003年   15篇
  2002年   15篇
  2001年   34篇
  2000年   19篇
  1999年   25篇
  1998年   28篇
  1997年   36篇
  1996年   34篇
  1995年   27篇
  1994年   24篇
  1993年   21篇
  1992年   18篇
  1991年   15篇
  1990年   7篇
  1989年   13篇
  1988年   6篇
  1987年   9篇
  1986年   8篇
  1985年   8篇
  1984年   10篇
  1983年   6篇
  1982年   5篇
  1981年   4篇
  1980年   5篇
  1979年   4篇
  1978年   5篇
  1977年   5篇
  1976年   4篇
  1971年   4篇
排序方式: 共有1710条查询结果,搜索用时 0 毫秒
101.
102.
103.
104.
Human T‐cell leukemia virus type I (HTLV‐1) infection is endemic in Japan, particularly clustered in the southwestern district, Kyushu‐Okinawa, which consists of eight prefectures that further consist of 274 municipalities. However, no information is available about the fine‐scale distribution of HTLV‐1 infection within Kyushu‐Okinawa. To assess the municipal‐level distribution of people with HTLV‐1 infection in Kyushu‐Okinawa, we performed a cross‐sectional study using a fine‐scale geographic information system map based on HTLV‐1 screening test results from the Japanese Red Cross database from September 2012 to February 2014. Of the 881 871 (646 914 male, 234 957 female) screened blood donors, 981 were seropositive for HTLV‐1 by confirmatory test. The seroprevalence was 0.11% (95% confidence interval [CI] 0.10%‐0.12%) for all, 0.094% (95% CI, 0.09%‐0.10%) for male, and 0.16% (95% CI, 0.14%‐0.18%) for female individuals. The sex‐ and age‐specific HTLV‐1 seroprevalence varied significantly across municipalities; particularly, the seroprevalence among women aged 50 years was significantly higher than that of men in both the mainland of Kyushu‐Okinawa and the satellite island, in all of which the seroprevalence of HTLV‐1 was more than 1.2%. These results show that, even in the Kyushu‐Okinawa district, there are endemic clusters of HTLV‐1 in small areas. This suggests that public health education programs are needed to eliminate new HTLV‐1 infection in these areas.  相似文献   
105.
106.
High prevalence of squamous anal lesions is linked to oncogenic human papillomavirus (HPV). Human immunodeficiency virus (HIV) promotes anal carcinogenesis. Epidermal growth factor receptor (EGFR), HER2/neu, c-Met, and vascular endothelial growth factor receptor-1 (VEGFR1) (tyrosine kinase growth factor receptors) are implicated in tumor progression, but little is known about their role in anal lesions. We investigated their expression and distribution in normal, dysplastic, and carcinomatous anal epithelium and then tried to analyze the effects on these variables of HPV and the HIV-positive status. Seventy-one HIV-positive and 47 HIV-negative patients were selected. We studied growth factor receptors, p16 and Ki67 expression, by in situ hybridization, fluorescent in situ hybridization (FISH) and chromogen in situ hybridization (CISH), immunocytochemistry, and morphological quantification in 226 lesions, either infected by HPV6 and 11 (31 condylomas acuminata) or infected with oncogenic HPVs (48 invasive cancers, 147 anal intraepithelial neoplasias). No HER2/neu was detected. Strong EGFR immunolabeling was not accompanied by gene amplification. The number and intensity of EGFR- and c-Met–immunoreactive cells increased significantly during lesion progression, highlighting the effects of oncogenic HPVs. EGFR, c-Met, VEGFR1, and p16 were coexpressed in 96% of invasive cancers. HIV-modified c-Met expression in condyloma acuminata (P < .008) and invasive cancers (P < .02). Strong HIV-related immunodeficiency and an absence of antiretroviral therapy increased c-Met and/or EGFR expression. HIV-positive anal cancers showed correlated c-Met and VEGFR1 (P < .003), strong p16 labeling, and an increased Ki67 proliferation. The finding that EGFR, c-Met, and VEGFR1 involved in carcinogenesis are well-represented and coexpressed in anal cancers, especially in HIV-positive population, suggests possible novel targeted treatments for anal diseases.  相似文献   
107.
108.
109.
110.
During the years 1971-1984 urinary oestriol excretion was tested in 51,427 patients (group 1). One or more low oestriol value was found in 10.7% of patients; in this group the stillbirth rate was 6.8 times higher, the neonatal death rate 3.8 times higher, and fetal growth retardation rate 3.5 times higher than in patients with normal oestriol values (all p less than 0.00001). During the years 1985-1989 a further 20,635 patients were tested (group 2) and 7.6% had one or more low oestriol value. The perinatal mortality rate in patients with normal oestriol excretion fell from 0.8% in group 1 to 0.5% in group 2 (p less than 0.005), and in patients with low oestriol excretion from 4.2% in group 1 to 2.4% in group 2 (p less than 0.002). However, patients in group 2 with low oestriol values still had significantly unfavourable results, compared to those with normal oestriol values--stillbirth rate 3.3 times higher, neonatal death rate 4.6 times higher, and fetal growth retardation rate 3.2 times higher (all p less than 0.00001). Intravenous dextrose and aminoacid infusions were given to 967 patients who had persistently low oestriol values in spite of rest in hospital, in an attempt to correct fetoplacental function; the perinatal mortality rate was 0.9% in the 660 (68.3%) who responded favourably, and 9.8% in the 307 (31.7%) who did not respond (p less than 0.0001).  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