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   801篇
  免费   46篇
  国内免费   4篇
耳鼻咽喉   2篇
儿科学   33篇
妇产科学   16篇
基础医学   101篇
口腔科学   13篇
临床医学   62篇
内科学   182篇
皮肤病学   20篇
神经病学   49篇
特种医学   36篇
外国民族医学   1篇
外科学   95篇
综合类   3篇
一般理论   1篇
预防医学   74篇
眼科学   97篇
药学   24篇
中国医学   4篇
肿瘤学   38篇
  2023年   7篇
  2022年   26篇
  2021年   48篇
  2020年   17篇
  2019年   27篇
  2018年   39篇
  2017年   15篇
  2016年   22篇
  2015年   21篇
  2014年   33篇
  2013年   29篇
  2012年   50篇
  2011年   71篇
  2010年   45篇
  2009年   17篇
  2008年   62篇
  2007年   55篇
  2006年   43篇
  2005年   35篇
  2004年   46篇
  2003年   34篇
  2002年   40篇
  2001年   13篇
  2000年   10篇
  1999年   6篇
  1998年   9篇
  1997年   5篇
  1995年   1篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1989年   3篇
  1988年   1篇
  1987年   1篇
  1986年   3篇
  1985年   3篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   3篇
  1976年   1篇
排序方式: 共有851条查询结果,搜索用时 31 毫秒
1.
To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians.  相似文献   
2.
3.
4.
PURPOSE: We reported that the expression of integrin-linked kinase (ILK) is up-regulated in ovarian carcinomas and that ovarian cancer cells have high expression of ILK. In this study, we have examined the expression of cell-free 59 kDa immunoreactive (ir)ILK in the serum and peritoneal fluid (PTF) of patients with ovarian cancer and evaluated its potential as a serum biomarker for early-stage screening and for monitoring clinical status of patients after chemotherapy treatment. EXPERIMENTAL DESIGN: Thirty-six serum specimens, including normal (n = 6), benign (n = 6), borderline (n = 4), grade 1 (n = 5), grade 2 (n = 5), and grade 3 (n = 10), were evaluated for the expression of irILK by Western blotting. The expression of irILK was evaluated in PTF (n = 10) and peritoneal washings from women with benign ovarian cysts (n = 4). In addition, tissue-conditioned medium obtained from the cultures of primary ovarian tumors (n = 9) was examined for the presence of irILK. Finally, the potential of serum irILK as a biomarker for ovarian cancer screening was evaluated by comparison with cancer antigen 125 (CA 125) concentrations in cancer patients before and after chemotherapy. RESULTS: irILK expression was present in normal serum and in serum of patients with benign ovarian tumors. irILK expression was 6-9-fold higher in the serum of patients with grade 1, grade 2, and grade 3 ovarian cancer than in the serum of healthy volunteers and patients with benign ovarian tumors (P < 0.01). Enhanced expression of irILK in the serum of ovarian cancer patients correlated with the concentration of CA 125. High expression of irILK was present in all 10 PTF tested. Tissue-conditioned medium prepared from malignant ovarian tumors had 4-fold more irILK expression than conditioned medium obtained from borderline and benign tumors (P < 0.01). irILK expression in serum of cancer patients was reduced to basal normal levels after six cycles of Taxol/carboplatin and was consistent with the change of CA 125 levels before and after chemotherapy. CONCLUSIONS: These data suggest that irILK is an ovarian tumor-associated antigen and implicates its potential not only as a biomarker for early-stage screening but also as a marker for monitoring the clinical condition of patients after treatment.  相似文献   
5.
6.
7.
Mothers are often responsible for preparing nutritious foods in their households. However, the quality of mother's diets is often neglected, which may affect both mother's and child's nutrition. Because no single food contains all necessary nutrients, diversity in dietary sources is needed to ensure a quality diet. We aimed to study the association between mother's dietary diversity and stunting in children <2 years attending Dhaka Hospital of icddr,b, a diarrhoeal disease hospital in Dhaka, Bangladesh. A case–control study (n = 296) was conducted from November 2016 to February 2017. Data were collected from mothers of stunted children <2 years (length‐for‐age z score [LAZ] < ?2) as “cases” and nonstunted (LAZ ≥ ?1) children <2 years as “controls.” Mothers were asked to recall consumption of 10 defined food groups 24 hr prior to the interview as per Guidelines for Minimum Dietary Diversity for Women. Among the mothers of cases, 58% consumed <5 food groups during the last 24 hr, compared with 45% in control mothers (P = 0.03). Children whose mothers consumed <5 food groups were 1.7 times more likely to be stunted than children whose mothers consumed ≥5 food groups (P = 0.04). Intake of food groups such as pulses, dairy, eggs, and vitamin A rich fruit was higher in control mothers. Proportion of mother's illiteracy, short stature, monthly family income <BDT 11,480, absence of bank account, and poor sanitation was also found to be higher in stunted group. Further study particularly intervention or longitudinal study to see the causality of mother's dietary diversity with child stunting is recommended.  相似文献   
8.
9.
Primary (localized) non-Hodgkin lymphoma (NHL) of the ovary is extremely rare; only a few cases have been reported in the literature. We report two cases of primary ovarian lymphoma (POL), one involving bilateral ovaries in a 15-year-old girl and other involving one ovary in a 5-year-old girl. This report describes detailed clinical, histopathological, and imaging findings, along with the review of literature of primary diffuse large B-cell lymphoma (DLBCL) arising from an ovary. In addition, we describe findings of targeted capture panel sequencing on both tumors and identify the major genetic mutations that are recurrently mutated in pan-cancers. Compared to the genomic mutation features of major subtypes of DLBCL, we distinguish that each POL belongs to distinctive subtypes, GCB (germinal center B-cell subtype) DLBCL and ABC (activated B-cell subtype) DLBCL, respectively. The findings from the genomic analysis may help to understand the pathogenesis of POL and to guide potential targeted therapy in the future.  相似文献   
10.
Gall bladder Carcinoma (GBC) is the fifth most common cancer of the digestive tract and frequently diagnosed in late stage of disease. Estimation of circulating free DNA (cfDNA) in serum has been applied as a “liquid biopsy” in several deep seated malignancies. Its value in diagnosis of gall bladder carcinoma has not been studied. The present study was designed to assess the role of cfDNA in the diagnosis of GBC and correlate levels with the TNM stage. Serum was collected from 34 patients with GBC and 39 age and sex matched controls including 22 cholecystitis and 17 healthy individuals. Serum cfDNA levels were measured through quantitative polymerase chain reaction (qPCR) by amplification of β-globin gene. Performance of the assay was calculated through the receiver operating characteristic (ROC) curve. The cfDNA level was significantly lower in healthy controls and cholecystitis (89.32 ± 59.76 ng/ml, 174.21 ± 99.93 ng/ml) compared to GBC (1245.91 ± 892.46 ng/ml, p = <0.001). The cfDNA level was significantly associated with TNM stage, lymph node involvement and jaundice (0.002, 0.027, and 0.041, respectively). Area under curve of ROC analysis for cancer group versus healthy and cholecystitis group was 1.00 and 0.983 with sensitivity of 100 %, 88.24 % and specificity of 100 % respectively. Quantitative analysis of cfDNA may distinguish cholecystitis and gall bladder carcinoma and may serve as new diagnostic, noninvasive marker adjunct to imaging for the diagnosis of GBC.  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