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   257篇
  免费   21篇
耳鼻咽喉   8篇
儿科学   8篇
妇产科学   14篇
基础医学   24篇
口腔科学   19篇
临床医学   17篇
内科学   71篇
皮肤病学   1篇
神经病学   8篇
特种医学   10篇
外科学   45篇
综合类   6篇
预防医学   16篇
眼科学   4篇
药学   12篇
肿瘤学   15篇
  2023年   5篇
  2022年   2篇
  2021年   10篇
  2020年   4篇
  2019年   4篇
  2018年   6篇
  2017年   8篇
  2016年   7篇
  2015年   15篇
  2014年   9篇
  2013年   16篇
  2012年   20篇
  2011年   20篇
  2010年   9篇
  2009年   12篇
  2008年   30篇
  2007年   31篇
  2006年   21篇
  2005年   17篇
  2004年   8篇
  2003年   3篇
  2002年   1篇
  2001年   1篇
  2000年   2篇
  1999年   1篇
  1996年   1篇
  1995年   2篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
  1991年   5篇
  1989年   1篇
  1983年   1篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
排序方式: 共有278条查询结果,搜索用时 0 毫秒
1.
Live and boiled cells of 16 strains of Aeromonas caviae, isolated from patients with diarrhea, agglutinated with Shigella boydii 5 antiserum in a slide test. Further studies with seven selected strains showed agglutination with boiled cells in a tube test. Lipopolysaccharide antigen extracted from one of these strains cross-reacted with S. boydii 5 in enzyme-linked immunosorbent assay and immunoblot studies. Either all or the majority of the seven strains possessed properties deemed to be diarrheagenic.  相似文献   
2.
To determine the prevalence of infection with Campylobacter fetus subsp. jejuni in Bangladesh, culture surveys were conducted among three populations. In Dacca, Campylobacter was isolated from 5.2% of 97 individuals with clinical dysentery and from 12.3% of 204 patients with only diarrhea. This difference may have resulted from a greater representation of young children in the second group. Campylobacter was isolated from 17.7% of the 141 healthy village children aged 1 to 5.5 years and from 38.8% of the 1-year-old children. More infected children (48%) had a history of recent diarrheal illness than did a group of matched controls (20%; P = 0.016). These findings suggest that campylobacter infection is common for Bangladeshi children. However, this organism may not cause diarrheal illness in all instances in which it is isolated.  相似文献   
3.
4.
5.
The relation between cancer and coagulation is the subject of investigation since a relation between tumor and thrombosis has been determined. Antithrombin III is an important thrombin inhibitor, and increased thrombin?Cantithrombin (TAT) complex levels activate coagulation. Activated thrombin activatable fibrinolysis inhibitor (TAFI) inhibits the conversion of plasminogen to plasmin. In addition, it directly inactivates plasmin. Defective fibrinolysis increases the risk of thrombosis. In this study, we evaluated homeostatic parameters, TAFI, and TAT levels in patients with gastric cancer applying to the medical oncology outpatient clinic. Fifty-two patients and 35 healthy controls were included. ELISA was used to measure TAFI and TAT complex levels. These were statistically higher in the patient group (p?<?0.05 and p?=?0.001, respectively). D-dimer levels were higher in stage IV (p?=?0.05). Correlations between lymph nodes and TAFI and TAT levels were examined. Weak but positive correlation between lymph nodes and TAFI was detected (R?=?0.452, p?=?0.027). TAFI and TAT levels were evaluated using relative operating characteristic analysis to differentiate the disease. TAT was more specific than TAFI according to this analysis (TAFI area under curve (AUC), 0.676; TAT AUC, 0.874). Thrombotic events and bleeding disorders need to be borne in mind in gastric cancer. This situation is due to the impairment of the balance between coagulation and fibrinolysis. Further studies are now needed to evaluate the effects of TAFI and TAT on survey and prognosis as well as the potential of these parameters as tumor markers for gastric cancer.  相似文献   
6.
Objectives: To determine whether the cellular inflammatory markers of activated macrophages, neopterin (NEO), chitotriosidase activity and the acute-phase inflammatory marker C-reactive protein (CRP) are elevated in pregnancy with threatened preterm labor (TPL).

Methods: Thirty-two pregnant women with TPL and 32 women with uncomplicated pregnancy (UP) were included this study. The primary aim was to compare the NEO, chitotriosidase activity and CRP levels between women with TPL and women with UP.

Results: NEO levels were all significantly elevated in patients with TPL compared to UP (median 25–75%; 9.61 [8.47–12.29] versus 4.46 [3.59–6.92], respectively; p?p?=?0.036). However, CRP levels were not different in women with TPL compared to UP (p?=?0.573). Furthermore, a significant moderate negative correlation was found between delivery week and NEO level (r?=??0.557, p?=?0.001). However, a significant correlation was not seen between delivery week and chitotriosidase activity (r?=??0.042, p?=?0.741).

Conclusions: Inflammatory markers such as NEO and chitotriosidase activity, which are markers of macrophages, are more elevated in pregnant women with TPL than in women with UP. These data suggest that there are striking increases in inflammation and cellular immune activation in TPL.  相似文献   
7.
Background: Inorganic arsenic is one of the most common naturally occurring contaminants found in the environment. Arsenic is associated with a number of health outcomes, with epigenetic modification suggested as a potential mechanism of toxicity.Objective: Among a sample of 400 adult participants, we evaluated the association between arsenic exposure, as measured by blood and urinary total arsenic concentrations, and epigenome-wide white blood cell DNA methylation.Methods: We used linear regression models to examine the associations between arsenic exposure and methylation at each CpG site, adjusted for sex, age, and batch. Differentially methylated loci were subsequently examined in relation to corresponding gene expression for functional evidence of gene regulation.Results: In adjusted analyses, we observed four differentially methylated CpG sites with urinary total arsenic concentration and three differentially methylated CpG sites with blood arsenic concentration, based on the Bonferroni-corrected significance threshold of p < 1 × 10–7. Methylation of PLA2G2C (probe cg04605617) was the most significantly associated locus in relation to both urinary (p = 3.40 × 10–11) and blood arsenic concentrations (p = 1.48 × 10–11). Three additional novel methylation loci—SQSTM1 (cg01225779), SLC4A4 (cg06121226), and IGH (cg13651690)—were also significantly associated with arsenic exposure. Further, there was evidence of methylation-related gene regulation based on gene expression for a subset of differentially methylated loci.Conclusions: We observed significant associations between arsenic exposure and gene-specific differential white blood cell DNA methylation, suggesting that epigenetic modifications may be an important pathway underlying arsenic toxicity. The specific differentially methylated loci identified may inform potential pathways for future interventions.Citation: Argos M, Chen L, Jasmine F, Tong L, Pierce BL, Roy S, Paul-Brutus R, Gamble MV, Harper KN, Parvez F, Rahman M, Rakibuz-Zaman M, Slavkovich V, Baron JA, Graziano JH, Kibriya MG, Ahsan H. 2015. Gene-specific differential DNA methylation and chronic arsenic exposure in an epigenome-wide association study of adults in Bangladesh. Environ Health Perspect 123:64–71; http://dx.doi.org/10.1289/ehp.1307884  相似文献   
8.
Epidemiologic and clinical features of infection with Campylobacter jejuni in Bangladesh were examined in (1) diarrheal patients infected with C jejuni, (2) healthy control subjects, and (3) village children who were cultured monthly and at each diarrheal episode during a 10-month period. C jejuni was isolated from 437 (14%) of 3,038 outpatients with diarrhea. These patients had no distinct clinical presentation and were more likely to have a mixed infection than were patients infected with other pathogens (59% vs 42%, P less than 0.01). Age-specific infection rates were greatest in infants and did not differ significantly from those in control subjects. C jejuni was isolated less frequently from village children with diarrhea than from those cultured routinely (5% vs 9%, P less than 0.05). Forty percent of 47 patients with C jejuni vs 23% of 48 control subjects (P less than 0.01) had an elevated convalescent-phase antibody titer as determined by complement fixation test. In Bangladesh, enteric infection with C jejuni is common but often asymptomatic, although pathogenicity is suggested by serologic response in some patients.  相似文献   
9.
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