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   5338篇
  免费   357篇
  国内免费   140篇
耳鼻咽喉   7篇
儿科学   12篇
妇产科学   6篇
基础医学   300篇
口腔科学   1742篇
临床医学   495篇
内科学   861篇
皮肤病学   123篇
神经病学   455篇
特种医学   258篇
外科学   124篇
综合类   702篇
现状与发展   2篇
预防医学   210篇
眼科学   42篇
药学   261篇
  5篇
中国医学   203篇
肿瘤学   27篇
  2023年   99篇
  2022年   182篇
  2021年   237篇
  2020年   195篇
  2019年   203篇
  2018年   203篇
  2017年   184篇
  2016年   170篇
  2015年   156篇
  2014年   373篇
  2013年   327篇
  2012年   285篇
  2011年   284篇
  2010年   225篇
  2009年   197篇
  2008年   249篇
  2007年   229篇
  2006年   194篇
  2005年   168篇
  2004年   130篇
  2003年   131篇
  2002年   84篇
  2001年   115篇
  2000年   72篇
  1999年   51篇
  1998年   59篇
  1997年   65篇
  1996年   69篇
  1995年   64篇
  1994年   51篇
  1993年   60篇
  1992年   80篇
  1991年   61篇
  1990年   53篇
  1989年   47篇
  1988年   47篇
  1987年   45篇
  1986年   43篇
  1985年   44篇
  1984年   40篇
  1983年   42篇
  1982年   40篇
  1981年   28篇
  1980年   31篇
  1979年   15篇
  1978年   15篇
  1977年   22篇
  1976年   17篇
  1975年   24篇
  1974年   10篇
排序方式: 共有5835条查询结果,搜索用时 15 毫秒
71.
BackgroundPrevotella intermedia/nigrescens is one of the well-known pathogens causing periodontal diseases, and the red florescence excited by the visible blue light caused by the protoporphyrin IX in the bacterial cells could be useful for the chair-side detection. The aim of this study was to evaluated levels of periodontal pathogen, especially P. intermedia in clinical samples of red fluorescent dental plaque.MethodsThirty two supra gingival plaque samples from six individuals were measured its fluorescence at 640 nm wavelength excited by 409 nm. Periodontopathic bacteria were counted by the Invader PLUS PCR assay. Co-relations the fluorescence intensity and bacterial counts were analyzed by Person’s correlation coefficient and simple and multiple regression analysis. Positive and negative predictive values of the fluorescence intensities for with or without P. intermedia in supragingival plaque was calculated.ResultsWhen relative fluorescence unit (RFU) were logarithmic transformed, statistically significant linear relations between RFU and bacterial counts were obtained for P. intermedia, Porphyromonas gingivalis and Tannerella forsythia. By the multiple regression analysis, only P. intermedia had statistically significant co-relation with fluorescence intensities. All of the fluorescent dental plaque contained P. intermedia m. In contrast, 28% of non-fluorescent plaques contained P. intermedia.ConclusionTo check the fluorescence dental plaque in the oral cavity could be the simple chair-side screening of the mature dental plaque before examining the periodontal pathogens especially P. intermedia by the PCR method.  相似文献   
72.
73.
74.
Posterior polar cataract is a rare form of congenital cataract. It is usually inherited as an autosomal dominant disease, yet it can be sporadic. Five genes have been attributed to the formation of this disease. It is highly associated with complications during surgery, such as posterior capsule rupture and nucleus drop. The reason for this high complication rate is the strong adherence of the opacity to the weak posterior capsule. Different surgical strategies were described for the handling of this challenging entity, most of which emphasized the need for gentle maneuvering in dealing with these cases. It has a unique clinical appearance that should not be missed in order to anticipate, avoid, and minimize the impact of the complications associated with it.  相似文献   
75.
This publication describes the history of minimal intervention dentistry (MID) for managing dental caries and presents evidence for various carious lesion detection devices, for preventive measures, for restorative and non‐restorative therapies as well as for repairing rather than replacing defective restorations. It is a follow‐up to the FDI World Dental Federation publication on MID, of 2000. The dental profession currently is faced with an enormous task of how to manage the high burden of consequences of the caries process amongst the world population. If it is to manage carious lesion development and its progression, it should move away from the ‘surgical’ care approach and fully embrace the MID approach. The chance for MID to be successful is thought to be increased tremendously if dental caries is not considered an infectious but instead a behavioural disease with a bacterial component. Controlling the two main carious lesion development related behaviours, i.e. intake and frequency of fermentable sugars, to not more than five times daily and removing/disturbing dental plaque from all tooth surfaces using an effective fluoridated toothpaste twice daily, are the ingredients for reducing the burden of dental caries in many communities in the world. FDI's policy of reducing the need for restorative therapy by placing an even greater emphasis on caries prevention than is currently done, is therefore, worth pursuing.  相似文献   
76.
BackgroundCarotid atherosclerosis is a powerful predictive factor of vascular risk at the individual patient level. Ultrasonography is a reference technique for the evaluation of this condition. However, its use in common practice remains difficult due to a lack of standardization and inter-operator variability. We present a new and simple technique for the assessment of carotid atherosclerosis; and evaluate the ability of vascular neurologists to obtain results consistent with those of an expert in vascular ultrasound.Material and methodsThe TIMMA scale is an acronym for the five classes of carotid atherosclerosis in French, VIMMA in English: very important, important, moderate, minimal and absent. Combined, the first two classes make up the group “significant atheroma” and the last three classes make up the group “no significant atheroma”. This scale was evaluated in 38 patients (76 carotid arteries) suffering from ischemic stroke or transient ischemic attack by five operators who are competent in carotid echocardiography: one TIMMA-trained (40 hours of training) vascular neurologist physician (VNP), three VNPs informed on the measurement method (1 hour of information) and one specialized vascular physician (SVP) who was considered to be the reference examiner. We evaluated the concordance between the VNPs and the SVP in classifying patients, firstly into the significant or not atheroma group and, secondly, into the five TIMMA classes.ResultsThe evaluation of the two-group clustering scale found a concordance between the informed VNPs and the SVP on 76 carotid arteries of 86% (kappa = 0.7) and between the trained VNP and the SVP on 58 carotid arteries of 90% (kappa = 0.8). The positive and negative predictive values for significant atheroma diagnosis were 100% and 81%, respectively, for the informed VNPs, and 100% and 80% for the trained VNP. The evaluation of the Five-Class Scale showed a concordance between the informed VNPs and the SVP of 46% (kappa = 0.3), and between the trained VNP and the SVP of 74% (kappa = 0.7).ConclusionTIMMA allows VNPs who are competent in carotid ultrasonography to reproducibly identify subjects with significant carotid atheroma. The contribution of this scale to the determination of cardiovascular risk should be evaluated.  相似文献   
77.
Whatever his or her disability, a person has the right to medical care of the same quality as any other patient. The law tries to meet the needs of vulnerable people, regardless of their situation. For example, a minor, disabled or not, may seek a treatment while preserving confidentiality regarding his/her parents. Privacy is a concept that does not begin at 18. In France, the law of 4 March 2002 already addressed this hypothesis; the law of 26 January 2016 modernizing our health system extended it. An adult, disabled or not, may need help not only for administrative and financial procedures, but also for medical or medicosocial matters. The law offers various support solutions with the family, guardian, support person, relatives, caregivers, attorneys involved with a mandate for future protection. In medical practice, a number of situations, simple in theory, can be very problematic. The ethical approach will be essential to help deal with all these questions.  相似文献   
78.
79.
Vascular calcification plays a prominent role in cardiovascular disease. Once considered to be a passive consequence of aging, this pathological process is now accepted to be dynamic and tightly regulated, its onset triggered by inflammation and necrosis and its progression bearing key similarities to osteogenesis. A major potential advance in our ability to understand the natural history and clinical implications of vascular calcification is the detection of its early and dynamic stages through the use of the positron-emitting radiotracer, 18F-sodium fluoride. Alongside anatomical information gained from computed tomography, hybrid positron emission and computed tomography (PET/CT) imaging with 18F-sodium fluoride has, for the first time, enabled the non-invasive detection of microcalcification within the aortic valve, great vessels, and vulnerable coronary plaque. This has raised promise that exploring this process may allow improved risk prediction, better application of current therapies and ultimately the development of novel treatments to target this widespread pathology.  相似文献   
80.
The 52‐week results from the CLEAR (NCT02074982) study showed high and superior efficacy of secukinumab versus ustekinumab in clearing skin and improving patient‐reported outcomes, with comparable safety profile in subjects with moderate to severe psoriasis. Here, we analyzed the efficacy and safety of secukinumab in Asian subjects from the CLEAR study. In this double‐blind, phase IIIb study, eligible subjects with moderate to severe plaque psoriasis were randomized (1:1) to receive s.c. injection of secukinumab 300 mg or ustekinumab as per label. Of 62 subjects included in Asian subanalyses, 23 were randomized to secukinumab and 39 to ustekinumab. A significantly higher proportion of subjects achieved 90% or more improvement in Psoriasis Area and Severity Index (PASI 90) with secukinumab versus ustekinumab at week 16 (78.3% vs 35.9%, = 0.0010) and at week 52 (60.9% vs 33.3%, = 0.0196). Similarly, a higher proportion of subjects achieved PASI 100 with secukinumab versus ustekinumab at week 16 (43.5% vs 10.3%, = 0.0029) and at week 52 (30.4% vs 12.8%, = 0.0704). The median time to achieve 50% improvement in baseline PASI was 2.8 weeks in the secukinumab group versus 6.3 weeks in the ustekinumab group. The safety profile of secukinumab was in line with the known profile and no deaths occurred. Overall, 95.7% and 84.6% of subjects remained on secukinumab and ustekinumab, respectively. Similar to the core study, secukinumab showed sustained and superior efficacy with faster response versus ustekinumab, and no new or unexpected safety concerns were identified, in Asian subjects with moderate to severe plaque psoriasis.  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