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   4782篇
  免费   450篇
  国内免费   33篇
耳鼻咽喉   81篇
儿科学   174篇
妇产科学   103篇
基础医学   541篇
口腔科学   73篇
临床医学   395篇
内科学   1006篇
皮肤病学   265篇
神经病学   266篇
特种医学   171篇
外科学   674篇
综合类   267篇
一般理论   7篇
预防医学   322篇
眼科学   296篇
药学   267篇
中国医学   18篇
肿瘤学   339篇
  2023年   63篇
  2022年   84篇
  2021年   173篇
  2020年   124篇
  2019年   138篇
  2018年   159篇
  2017年   110篇
  2016年   146篇
  2015年   163篇
  2014年   193篇
  2013年   215篇
  2012年   301篇
  2011年   353篇
  2010年   147篇
  2009年   169篇
  2008年   262篇
  2007年   253篇
  2006年   265篇
  2005年   222篇
  2004年   184篇
  2003年   170篇
  2002年   176篇
  2001年   117篇
  2000年   118篇
  1999年   116篇
  1998年   47篇
  1997年   37篇
  1996年   38篇
  1995年   33篇
  1994年   43篇
  1993年   46篇
  1992年   66篇
  1991年   57篇
  1990年   42篇
  1989年   45篇
  1988年   48篇
  1987年   60篇
  1986年   50篇
  1985年   43篇
  1984年   33篇
  1983年   19篇
  1982年   13篇
  1980年   9篇
  1979年   22篇
  1978年   14篇
  1977年   10篇
  1976年   8篇
  1974年   8篇
  1973年   12篇
  1967年   7篇
排序方式: 共有5265条查询结果,搜索用时 0 毫秒
81.
82.
Objective: To assess the relationship between the HLA-DRB1 genes with disease severity as assessed by radiological erosions in Malaysian patients with rheumatoid arthritis (RA).

Methods: In this cross-sectional study, we studied 61 RA patients who fulfilled the ACR criteria for the diagnosis of RA. HLA-DRB1 genotyping was performed by sequence specific primer (SSP)—PCR. Radiological grading and erosive score of the hands and wrists was calculated according to the Larsen–Dale method. Demographic data and treatment given to the patients were obtained from their case records.

Results: Fifty-six females and five males were studied from three ethnic groups. In 57 patients with erosions, rheumatoid factor was detected in 80%, HLA-DR4 in 40%, HLA-DRB1*0405 in 24% and shared epitope (SE) in 31%. The median delay in starting DMARDs was 24 months. The presence of rheumatoid factor, HLA-DR4 and HLA-DRB1*0405 were not significantly associated with a worse erosive score. Patients who possessed the SE had a higher erosive scores, compared to those who did not (p = 0.05). Concurrently, a delay in starting DMARD was associated with a high erosive score (p = 0.023, r = 0.348). However, after adjustment for the delay in starting DMARD, SE was no longer significantly associated with the erosive score.

Conclusions: In these patients, the delay in starting DMARDs had a greater influence on the erosive score than SE alone. Whilst we cannot discount the contribution of the SE presence, we would advocate early usage of DMARDs in every RA patient to reduce joint erosions and future disability.  相似文献   
83.
IntroductionContinuing Professional development (CPD) is deemed essential for the Radiographers (DR) and Radiation Therapists (RT) after Singapore commenced state registration. Diagnostic imaging and radiotherapy treatment services are constantly revolutionizing and those working in this field requires sufficient knowledge of the uptrends for training and development. The purpose of this survey is to identify the current training needs of the registered DR and RT in Singapore, and to understand their views about CPD activities.MethodsAn online questionnaire was disseminated by the Singapore Society of Radiographers (SSR) to all registered DR and RT in Singapore, and all practicing in restructured and private hospitals were included. Data collection took place from January 2018 to April 2018.Results102 responses were analysed, where 89 were DR and 13 were RT. CPD was provided in 72.5% (n = 74) of the participants’ institutions, and 69.6% (n = 71) of participants were aware of CPD. Interestingly, participants were significantly more likely to be unaware of CPD when working in an institution which do not offer CPD. Training programme objective was the most important factor for selecting a programme. 93.1% (n = 95) preferred SSR to support them for CPD. There were a few constraints to CPD engagements identified such as financial factors, lack of time, and institution availability.ConclusionThere was significant intrinsic motivation in a quality CPD activity. CPD activities should be current, accessible and relevant for the healthcare professionals to increase participation, which directly contributes to high standards of clinical care.Implications for practiceLocal healthcare institutions should be aware and address needs, gaps and aspirations of the local DR and RT community to ensure adequate preparation has been made upon initiation of mandatory CPD.  相似文献   
84.
Currently the best indicator for surgical treatment of arteriosclerosis is the degree of stenosis. Although X-ray angiography is currently the standard, cost and morbidity are distinct disadvantages. By modelling stenosis and studying its biofluid mechanics, one can apply its results in the field of arterial disease research. This formed the motivation for this work. A non-Newtonian (power law) incompressible Navier-Stokes (N- S) solver was developed using the method of operator splitting and artificial compressibility. The vehicle used is the computational fluid dynamics (CFD) numerical library FASTFLO. The power-law model developed is then used to do a parametric study of the effect of 'n' on blood flow mechanics where 'n' is the power index that determines the haematocrit of blood. A pulsatile pressure wave over a cardiac cycle of a second was used to simulate transient flow over a hypothetical twodimensional stenotic geometry. By comparing the different velocity pressure, wall shear stress and viscosity profiles, it has been found when 'n' increases, the vortex formation and peak wall shear stress decreases (magnitudes of < 1.5 Pa). Since the formation of vortices and lowoscillatory wall shear stress on the stenotic wall is detrimental to the well-being of the arterial tract, it can therefore be inferred that there might be a relationship between the diseased state of blood (power law) and early genesis of atherosclerosis. However, the conclusion of this paper marks the advent of new research directions in this field of study.  相似文献   
85.
86.
ObjectiveExtant studies indicate that just one characteristic of sexual assault cannot properly represent the whole experience of sexual assault and, especially, the severity of sexual assault. This study aimed to understand the totality of sexual assault experiences and elucidate subtypes of sexual assault victims based on the detailed characteristics of their sexual assault experiences and those relationships with mental health. MethodsA total of 255 adult sexual violence victims who used intervention services and a comparison group were included. Information on their sexual assault experiences was gleaned from case records data. ResultsThe following four distinctive profile groups were identified: “Sexual Touching” (19.6%), “Rape/Social Relation” (30.4%), “Intimate Partner Violence (IPV)” (18.8%), and “Rape/Stranger” (31.3%). The subgroups differed in terms of secondary victimization and adverse childhood experiences. The Rape/Social Relation and IPV subgroups most frequently experienced secondary victimization and childhood adversity. The four profile subgroups demonstrated different relationships with mental health outcomes, with a complicated pattern. The Rap/Social Relation and IPV subgroups scored higher on mental health problem screening measures compared to other groups. However, a considerable proportion of victims in the Sexual Touching subgroup also reported suicidal behaviors and self-injury. ConclusionBased on the results, theoretical and clinical implications were discussed.  相似文献   
87.
88.
89.

Background

Medications have been increasingly used by patients for the treatment of their systemic diseases. However, many drugs are reported to induce oral lichenoid lesions (OLL).

Aim

The aim of our study was to investigate the relationship between OLL, medications, and folate and vitamin B12 levels.

Material and Methods

Twenty Thai patients who were diagnosed with OLL by clinical and histopathological examination were included in this study. These subjects were compared with 24 healthy control subjects. Complete blood counts, hemoglobin typing, serum and red cell folate, and serum vitamin B12 levels were investigated. The medications taken and the systemic diseases of the Thai patients with OLL were recorded and analyzed.

Results

Our results showed that only 1/20 patients with OLL (5%) had low red cell folate and only 1 case showed a low level of serum folate. Vitamin B12 levels were within normal range in both groups. There were no significant differences in red cell folate, serum folate, or vitamin B12 levels between the patients with OLL and the control group (p>0.05). Four cases in OLL and 3 cases in the control group had low hematocrit less than 36% and they were defined as anemic.

Conclusion

Antihypertensives and hypolipidemics were the most common medications taken by patients with OLL; however, these drugs had no effect on red cell folate, serum folate, or vitamin B12 levels. Since the patients were taking multiple drugs and we could not confirm the diagnosis of OLDR by withdrawal of the drugs, we used the term OLL related drug instead.Key words: folate, lichenoid, medication, oral, Thai, vitamin B12  相似文献   
90.
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