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   558篇
  免费   44篇
  国内免费   3篇
耳鼻咽喉   17篇
儿科学   7篇
妇产科学   28篇
基础医学   101篇
口腔科学   29篇
临床医学   67篇
内科学   92篇
皮肤病学   5篇
神经病学   30篇
特种医学   13篇
外科学   30篇
综合类   26篇
预防医学   66篇
眼科学   16篇
药学   39篇
中国医学   11篇
肿瘤学   28篇
  2023年   14篇
  2022年   16篇
  2021年   50篇
  2020年   28篇
  2019年   28篇
  2018年   38篇
  2017年   29篇
  2016年   22篇
  2015年   33篇
  2014年   32篇
  2013年   40篇
  2012年   48篇
  2011年   48篇
  2010年   41篇
  2009年   15篇
  2008年   28篇
  2007年   40篇
  2006年   13篇
  2005年   6篇
  2004年   13篇
  2003年   4篇
  2002年   5篇
  2001年   2篇
  2000年   1篇
  1997年   1篇
  1994年   3篇
  1992年   1篇
  1991年   1篇
  1987年   1篇
  1986年   3篇
  1983年   1篇
排序方式: 共有605条查询结果,搜索用时 15 毫秒
81.
ObjectivesTo evaluate gamma-glutamyltransferase (GGT), alanine transaminases (ALT) and aspartate transaminases (AST) levels and prevalent gestational diabetes mellitus (GDM).Design and methodsRandom plasma glucose, GGT, ALT and AST and the 50-g glucose challenge test were done on antenatal women followed by diagnostic 3-point 75-g oral glucose tolerance test within two weeks. GDM was diagnosed by ADA (2011) criteria.ResultsThe GDM rate was 12.2% (319/2610). Mean GGT level was higher in GDM women, 18 ± 12 vs. 16 ± 11 IU/L; P = 0.03. The risk for GDM was higher for women in the highest GGT quartile band compared to the lowest: RR 1.35 95%CI 1.0–1.8; P = 0.04. However, after adjustment for confounders, GGT was no longer associated with GDM. There was no correlation between ALT and AST levels and GDM.ConclusionsLiver transaminases do not predict GDM in contrast to type 2 diabetes.  相似文献   
82.
Novel 4″-O-benzimidazolyl clarithromycin derivatives were designed, synthesized and evaluated for their in vitro antibacterial activities. These benzimidazolyl derivatives exhibited excellent activity against erythromycin-susceptible strains better than the references, and some of them showed greatly improved activity against erythromycin-resistant strains. Compounds 16 and 17, which have the terminal 2-(4-methylphenyl)benzimidazolyl and 2-(2-methoxyphenyl)benzimidazolyl groups on the C-4″ bishydrazide side chains, were the most active against erythromycin-resistant Staphylococcus pneumoniae expressing the erm gene and the mef gene. In addition, compound 17 exhibited the highest activity against erythromycin-susceptible S. pneumoniae ATCC49619 and Staphylococcus aureus ATCC25923 as well. It is worth noting that the 4″-O-(2-aryl)benzimidazolyl derivatives show higher activity against erythromycin-susceptible and erythromycin-resistant strains than the 4″-O-(2-alkyl)benzimidazolyl derivatives.  相似文献   
83.
Demodicosis is an infestation of the skin with Demodex, an ectoparasite commonly found on the face. A cross-sectional study was conducted to detect the presence of the ectoparasite and the outcome of facial cleanser and moisturizer usage on its infestation. Universal sampling was performed among 390 medical students, age 20-25 years old in the Klang Valley of Malaysia. The biodata of the participants and information on the use of facial cleanser and moisturizer were obtained through questionnaire. Skin samples were obtained using both skin scraping and cellophane tape method and were subsequently examined directly by microscopy. The results show an overall prevalence of 17.2%. Males (21.5%) were affected more often than females (12.8%) (p = 0.022). There were no significant differences in the prevalence of the ectoparasite among different ethnic groups, age-groups and the presence of existing facial problems among the subjects. A lower infestation rate (11.45%) was found to be associated with the use of a moisturizer (p = 0.033). Both species of ectoparasites that infest man, Demodexfolliculorum and D. brevis, were detected in this study either as single or mixed infestations.  相似文献   
84.
Objective: This study aimed to determine prevalence of latent tuberculosis infection among medical students and tuberculosis exposure at the health facilities. Methods: A cross-section of study year 1(n=68) and year 5(n=75) medical students in a local university were recruited for latent tuberculosis infection testing using QuantiFERON-TB Gold Plus and a questionnaire analyzed for multivariate risk. Results: The majority of the study were vaccinated with BCG. None of year 1 medical students were positive for latent tuberculosis infection, however, six(8.0%) year 5 students were tested positive for latent tuberculosis infection. A higher incidence of year 5 medical students claimed to be exposed to tuberculosis at health facility(65.3% vs. 4.4%) and a higher percentage reported contact with tuberculosis case over the preceding year compared to year 1 students(30.7% vs. 8.8%). Conclusion: We observed a higher incidence of latent tuberculosis infection and higher exposure to tuberculosis in health facilities among year 5 medical students. Baseline screening and monitoring for progression to tuberculosis infection may benefit tuberculosis management programs.  相似文献   
85.
86.
Objective: The aims of the present study were to determine the effects of language background on the performance of the pitch pattern sequence test (PPST) and duration pattern sequence test (DPST). As temporal order sequencing may be affected by age and working memory, these factors were also studied. Design: Performance of tonal and non-tonal language speakers on PPST and DPST were compared. Study sample: Twenty-eight native Mandarin (tonal language) speakers and twenty-nine native Malay (non-tonal language) speakers between seven to nine years old participated in this study. Results: The results revealed that relative to native Malay speakers, native Mandarin speakers demonstrated better scores on the PPST in both humming and verbal labeling responses. However, a similar language effect was not apparent in the DPST. An age effect was only significant in the PPST (verbal labeling). Finally, no significant effect of working memory was found on the PPST and the DPST. Conclusion: These findings suggest that the PPST is affected by tonal language background, and highlight the importance of developing different normative values for tonal and non-tonal language speakers.  相似文献   
87.
88.
BackgroundMild cognitive impairment (MCI) is a neurocognitive state between normal cognitive aging and dementia, with evidence of neuropsychological changes but insufficient functional decline to warrant a diagnosis of dementia. Individuals with MCI are at increased risk for progression to dementia; and an appreciable proportion display neuropsychiatric symptoms (NPS), also a known risk factor for dementia. Cerebrovascular disease (CVD) is thought to be an underdiagnosed contributor to MCI/dementia. The Ginkgo biloba extract, EGb 761®, is increasingly being used for the symptomatic treatment of cognitive disorders with/without CVD, due to its known neuroprotective effects and cerebrovascular benefits.AimsTo present consensus opinion from the ASian Clinical Expert group on Neurocognitive Disorders (ASCEND) regarding the role of EGb 761® in MCI.Materials & MethodsThe ASCEND Group reconvened in September 2019 to present and critically assess the current evidence on the general management of MCI, including the efficacy and safety of EGb 761® as a treatment option.ResultsEGb 761® has demonstrated symptomatic improvement in at least four randomized trials, in terms of cognitive performance, memory, recall and recognition, attention and concentration, anxiety, and NPS. There is also evidence that EGb 761® may help delay progression from MCI to dementia in some individuals.DiscussionEGb 761® is currently recommended in multiple guidelines for the symptomatic treatment of MCI. Due to its beneficial effects on cerebrovascular blood flow, it is reasonable to expect that EGb 761® may benefit MCI patients with underlying CVD.ConclusionAs an expert group, we suggest it is clinically appropriate to incorporate EGb 761® as part of the multidomain intervention for MCI.  相似文献   
89.
Medicinal plants have gained much interest in the prevention and treatment of common human disease such as cold and fever, hypertension and postpartum. Bioactive compounds from medicinal plants were synthesised using effective extraction methods which have important roles in the pharmaceutical product development. Orthosiphon aristatus (OA), Eurycoma longifolia (EL) and Andrographis paniculata (AP) are among popular medicinal herbs in Southeast Asia. The major compounds for these medicinal plants are polar bioactive compounds (rosmarinic acid, eurycomanone and andrographolide) which have multiple benefits to human health. The bioactive compounds are used as a drug to function against a variety of diseases with the support of scientific evidence. This paper was intended to prepare a complete review about the extraction techniques (e.g. OA, EL and AP) of these medicinal plants based on existing studies and scientific works. Suitable solvents and techniques to obtain their major bioactive compounds and their therapeutic potentials were discussed.  相似文献   
90.
ContextLipopolysaccharide (LPS) exacerbates systemic inflammatory responses and causes excessive fluid leakage. 2,4,6-Trihydroxy-3-geranyl acetophenone (tHGA) has been revealed to protect against LPS-induced vascular inflammation and endothelial hyperpermeability in vitro.ObjectiveThis study assesses the in vivo protective effects of tHGA against LPS-induced systemic inflammation and vascular permeability in endotoxemic mice.Materials and methodsBALB/c mice were intraperitoneally pre-treated with tHGA for 1 h, followed by 6 h of LPS induction. Evans blue permeability assay and leukocyte transmigration assay were performed in mice (n = 6) pre-treated with 2, 20 and 100 mg/kg tHGA. The effects of tHGA (20, 40 and 80 mg/kg) on LPS-induced serum TNF-α secretion, lung dysfunction and lethality were assessed using ELISA (n = 6), histopathological analysis (n = 6) and survivability assay (n = 10), respectively. Saline and dexamethasone were used as the negative control and drug control, respectively.ResultstHGA significantly inhibited vascular permeability at 2, 20 and 100 mg/kg with percentage of inhibition of 48%, 85% and 86%, respectively, in comparison to the LPS control group (IC50=3.964 mg/kg). Leukocyte infiltration was suppressed at 20 and 100 mg/kg doses with percentage of inhibition of 73% and 81%, respectively (IC50=17.56 mg/kg). However, all tHGA doses (20, 40 and 80 mg/kg) failed to prevent endotoxemic mice from lethality because tHGA could not suppress TNF-α overproduction and organ dysfunction.Discussion and conclusionstHGA may be developed as a potential therapeutic agent for diseases related to uncontrolled vascular leakage by combining with other anti-inflammatory agents.  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