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   6344篇
  免费   345篇
  国内免费   90篇
耳鼻咽喉   77篇
儿科学   95篇
妇产科学   106篇
基础医学   964篇
口腔科学   127篇
临床医学   568篇
内科学   1244篇
皮肤病学   182篇
神经病学   425篇
特种医学   304篇
外科学   910篇
综合类   45篇
现状与发展   1篇
一般理论   3篇
预防医学   312篇
眼科学   75篇
药学   702篇
中国医学   136篇
肿瘤学   503篇
  2023年   52篇
  2022年   189篇
  2021年   294篇
  2020年   140篇
  2019年   184篇
  2018年   209篇
  2017年   170篇
  2016年   228篇
  2015年   310篇
  2014年   386篇
  2013年   413篇
  2012年   565篇
  2011年   554篇
  2010年   333篇
  2009年   241篇
  2008年   379篇
  2007年   386篇
  2006年   295篇
  2005年   266篇
  2004年   222篇
  2003年   189篇
  2002年   144篇
  2001年   106篇
  2000年   81篇
  1999年   85篇
  1998年   39篇
  1997年   20篇
  1996年   22篇
  1995年   11篇
  1994年   9篇
  1993年   8篇
  1992年   31篇
  1991年   29篇
  1990年   25篇
  1989年   22篇
  1988年   10篇
  1987年   12篇
  1986年   6篇
  1985年   17篇
  1984年   5篇
  1983年   7篇
  1979年   5篇
  1974年   8篇
  1972年   5篇
  1971年   8篇
  1970年   4篇
  1969年   6篇
  1968年   14篇
  1967年   5篇
  1966年   4篇
排序方式: 共有6779条查询结果,搜索用时 15 毫秒
111.
112.
113.

Background

Metabolic syndrome has clinical implications for chronic liver disease, but the relationship between chronic hepatitis B and metabolic syndrome remains unclear. The aim of this study was to determine whether hepatitis B surface antigen (HBsAg) positivity is associated with metabolic syndrome.

Methods

Data were obtained from the Third Korean National Health and Nutrition Examination Survey (KNHANES). Participant sera were tested for HBsAg. Metabolic syndrome was defined according to the modified National Cholesterol Education Program Adult Treatment Panel III guidelines for Koreans.

Results

Of the 5108 participants, 209 (4.1%) tested positive for HBsAg, and 1364 (26.7%) were diagnosed with metabolic syndrome. The prevalence of metabolic syndrome was 23.4% in HBsAg-positive men, 31.5% in HBsAg-negative men, 18.6% in HBsAg-positive women, and 23.7% in HBsAg-negative women. After adjusting for multiple factors, male participants who tested positive for serum HBsAg had an odds ratio of 0.612 (95% confidence interval [CI] 0.375–0.998) for metabolic syndrome and an odds ratio of 0.631 (95% CI 0.404–0.986) for elevated triglycerides. Women who tested positive for serum HBsAg had an odds ratio of 0.343 (95% CI 0.170–0.693) for elevated triglycerides.

Conclusions

Positive results for serum HBsAg are inversely associated with metabolic syndrome in men and with elevated triglycerides in men and women. This suggests that elevated triglycerides may contribute to the inverse association between HBsAg and metabolic syndrome.Key words: chronic hepatitis B, metabolic syndrome, survey, triglycerides  相似文献   
114.
Objectives: In South Korea, latent tuberculosis infection (LTBI) screening is a critical strategy associated with efforts to reduce the incidence of tuberculosis (TB). Currently, only children with a known history of TB contact are considered as pediatric high-risk groups for LTBI, and consequently, LTBI screening is only provided to these children. However, to reduce the incidence of TB, the high-risk groups that undergo LTBI screening should be expanded. This study aimed to assess the risk factors for LTBI among children living in South Korea with no known history of TB contact for the identification of additional high-risk groups. We investigated the risk factors for LTBI among US visa applicant children, who undergo LTBI screening regardless of their TB contact history.

Methods: We obtained data on demographic characteristics, medical history, Bacillus Calmette–Guerin (BCG) vaccination history, and results of LTBI screening for children aged 2–14 years. A tuberculin skin test was used for the diagnosis of LTBI, and an induration of 10 mm or greater was used to define a positive test. Adjusted odds ratios and 95% confidence intervals were calculated to determine the association between clinical and demographic variables and LTBI.

Results: Of the 1,664 study participants, 91 (5.5%) had LTBI. The binary logistic regression analysis showed that children born in high TB burden foreign countries had the highest odds of LTBI when considering all the risk factors investigated. Increasing age, absence of BCG vaccination, and a previous diagnosis of asthma were also significant risk factors for LTBI.

Conclusion: These results indicate that children born in high TB burden foreign countries should be considered a high-risk group for LTBI in South Korea; the inclusion of these children in LTBI screening should be considered.  相似文献   

115.
Objectives: The enterovirus EV71 is a major pathogen of hand, foot, and mouth disease (HFMD) in children. Aseptic meningitis is the most common neurologic complication of EV71-induced HFMD. Lumbar puncture is a crucial procedure in the diagnosis of aseptic meningitis. It is often performed based on physicians’ clinical suspicion. A diagnostic method that can aid in deciding whether this procedure should be performed is necessary. Cytokines are speculated to be associated with neurologic complications. In this study, we aimed to find an indicator of the presence of aseptic meningitis in children with EV71-induced HFMD.

Methods: This cross-sectional study included children with EV71-induced HFMD. The children underwent lumbar puncture due to suspected aseptic meningitis. They were categorized into an aseptic meningitis complicated group (n = 54) and uncomplicated group (n = 47) based on the results of cerebrospinal fluid examination. Healthy children were included as controls (n = 51). The sample serum levels of tumor necrosis factor-α, interferon-γ, interleukin (IL)-1β, IL-2, IL-6, IL-8, IL-10, and IL-13 were detected using multiplexed fluorescent bead-based immunoassays.

Results: The levels of all cytokines were significantly higher in children with EV71-induced HFMD complicated with aseptic meningitis than in children with uncomplicated EV71-induced HFMD and controls (p < 0.001). Binary logistic regression analysis demonstrated that IL-6 had the strongest association with aseptic meningitis of all cytokines examined. According to receiver operating characteristic analysis, the optimal cutoff value for IL-6 was 66 pg/mL with maximum sensitivity and specificity.

Conclusions: The results of this study suggest the association between higher production of cytokine and aseptic meningitis among children with EV71-induced HFMD. IL-6 was also suggested as an indicator of aseptic meningitis. Rapid measurement of IL-6 could be useful in deciding whether physicians should perform lumbar puncture on children.  相似文献   

116.

Objectives:

This study was performed to investigate the relationship between the incidence of national notifiable infectious diseases (NNIDs) and meteorological factors, air pollution levels, and hospital resources in Korea.

Methods:

We collected and stored 660 000 pieces of publicly available data associated with infectious diseases from public data portals and the Diseases Web Statistics System of Korea. We analyzed correlations between the monthly incidence of these diseases and monthly average temperatures and monthly average relative humidity, as well as vaccination rates, number of hospitals, and number of hospital beds by district in Seoul.

Results:

Of the 34 NNIDs, malaria showed the most significant correlation with temperature (r=0.949, p<0.01) and concentration of nitrogen dioxide (r=-0.884, p<0.01). We also found a strong correlation between the incidence of NNIDs and the number of hospital beds in 25 districts in Seoul (r=0.606, p<0.01). In particular, Geumcheon-gu was found to have the lowest incidence rate of NNIDs and the highest number of hospital beds per patient.

Conclusions:

In this study, we conducted a correlational analysis of public data from Korean government portals that can be used as parameters to forecast the spread of outbreaks.  相似文献   
117.
118.
Many systemic drugs can induce ocular toxicity and several ocular side‐effects have been identified in clinical studies. However, it is difficult to detect ocular toxicity in preclinical studies because of the lack of appropriate evaluation methods. Optical coherence tomography (OCT) is useful because it can provide real‐time images throughout a study period, whereas histopathology only provides images of sacrificed animals. Using OCT alongside histopathology, attempts were made to find effective approaches for screening of drug‐induced ocular toxicity in monkeys. Such approaches could be used in preclinical studies prior to human trials. Six male cynomolgus monkeys (Macaca fascicularis Raffles) were orally administered one of six candidate MAPK/ERK kinase (MEK) inhibitors. Central serous chorioretinopathy, a known side‐effect of such inhibitors, was identified in four monkeys by OCT. Artifacts generated during tissue processing meant that histopathology could not detect edematous changes. Thus, OCT is a useful tool to detect ocular toxicity which cannot be detected by histopathology in preclinical studies. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
119.
120.
Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture. The Ag-exchanged NaY zeolite particles were characterized by FE-SEM, EDS, BET, and XRD studies. The prepared Ag-NaZ-loaded PVA/PAA composite membrane was characterized by FE-SEM, XRD, a swelling study, and contact angle measurements. Pervaporation characteristics were investigated in terms of Ag-NaZ concentrations within PVA/PAA membranes using diverse feed solution conditions. The preferential sorption of IPA/water mixtures for Ag-NaZ-introduced membranes were also determined by calculating the apparent activation energies of IPA and water permeation, respectively. As a result, flux and selectivity increased with the Ag-NaZ concentration to 5 wt% in the membrane. Optimum pervaporation performance was observed in a 5 wt% Ag-NaZ-incorporated membrane with a flux equal to 0.084 kg m−2 h−1 and a separation factor of 2717.9 at 40 °C from an 80 wt% IPA aqueous feed solution.

Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture.  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