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   3560篇
  免费   245篇
  国内免费   19篇
耳鼻咽喉   18篇
儿科学   37篇
妇产科学   55篇
基础医学   434篇
口腔科学   320篇
临床医学   333篇
内科学   944篇
皮肤病学   71篇
神经病学   202篇
特种医学   122篇
外科学   554篇
综合类   16篇
预防医学   252篇
眼科学   15篇
药学   169篇
中国医学   12篇
肿瘤学   270篇
  2023年   30篇
  2022年   59篇
  2021年   126篇
  2020年   88篇
  2019年   94篇
  2018年   120篇
  2017年   93篇
  2016年   103篇
  2015年   129篇
  2014年   146篇
  2013年   171篇
  2012年   279篇
  2011年   253篇
  2010年   161篇
  2009年   178篇
  2008年   238篇
  2007年   198篇
  2006年   201篇
  2005年   211篇
  2004年   209篇
  2003年   169篇
  2002年   159篇
  2001年   30篇
  2000年   21篇
  1999年   32篇
  1998年   29篇
  1997年   24篇
  1996年   16篇
  1995年   14篇
  1994年   10篇
  1993年   10篇
  1992年   19篇
  1991年   17篇
  1990年   20篇
  1989年   24篇
  1988年   18篇
  1987年   20篇
  1986年   12篇
  1985年   8篇
  1984年   12篇
  1983年   6篇
  1982年   7篇
  1980年   13篇
  1979年   6篇
  1978年   5篇
  1977年   7篇
  1970年   2篇
  1969年   4篇
  1966年   2篇
  1922年   2篇
排序方式: 共有3824条查询结果,搜索用时 11 毫秒
71.
72.
Stopping during walking, a dynamic motor task frequent in everyday life, is very challenging for ataxic patients, as it reduces their gait stability and increases the incidence of falls. This study was conducted to analyse the biomechanical characteristics of upper and lower body segments during abrupt stopping in ataxic patients in order to identify possible strategies used to counteract the instability in the sagittal and frontal plane. Twelve patients with primary degenerative cerebellar ataxia and 12 age- and sex-matched healthy subjects were studied. Time–distance parameters, dynamic stability of the centre of mass, upper body measures and lower joint kinematic and kinetic parameters were analysed. The results indicate that ataxic patients have a great difficulty in stopping abruptly during walking and adopt a multi-step stopping strategy, occasionally with feet parallel, to compensate for their inability to coordinate the upper body and to generate a well-coordinated lower limb joint flexor–extensor pattern and appropriate braking forces for progressively decelerating the progression of the body in the sagittal plane. A specific rehabilitation treatment designed to improve the ability of ataxic patients to transform unplanned stopping into planned stopping, to coordinate upper body and to execute an effective flexion–extension pattern of the hip and knee joints may be useful in these patients in order to improve their stopping performance and prevent falls.  相似文献   
73.
Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate choriocapillaris flow deficits (CC FD) in a group of eyes with Type 3 macular neovascularization (MNV) versus a...  相似文献   
74.
75.
Clostridium perfringens type D isolates cause enterotoxemia in sheep, goats, and probably cattle. While the major disease signs and lesions of type D animal disease are usually attributed to epsilon toxin, a class B select agent, these bacteria typically produce several lethal toxins. Understanding of disease pathogenesis and development of improved vaccines are hindered by the lack of a small-animal model mimicking natural disease caused by type D isolates. Addressing this need, we developed an oral challenge mouse model of C. perfringens type D enterotoxemia. When BALB/c mice with a sealed anus were inoculated by intragastric gavage with type D isolates, 7 of 10 type D isolates were lethal, as defined by spontaneous death or severe clinical signs necessitating euthanasia. The lethalities of the seven type D isolates varied between 14 and 100%. Clinical signs in the lethally challenged mice included seizures, convulsions, hyperexcitability, and/or depression. Mild intestinal gas distention and brain edema were observed at necropsy in a few mice, while histology showed multifocal acute tubular necrosis of the kidney and edema in the lungs of most challenged mice that developed a clinical response. When the lethality of type D isolates in this model was compared with in vitro toxin production, only a limited correlation was observed. However, mice could be protected against lethality by intravenous passive immunization with an epsilon toxin antibody prior to oral challenge. This study provides an economical new model for studying the pathogenesis of C. perfringens type D infections.  相似文献   
76.
We carried out fluorescence in situ hybridization (FISH) studies on 18 Ph+ chronic myeloid leukemia (CML) cases with chromosome 22 genomic deletions with the Vysis BCR-ABL dual-color/dual-fusion probe (BCR-ABL DC/DF) to compare the hybridization patterns obtained with this approach to those obtained with the "home brew" BAC/PAC system. Our results are the following: chromosome 22 microdeletions less than 400 kilobases (Kb) were not detected by the BCR DC/DF probe; FISH analysis with the BCR DC/DF probe in cases bearing chromosome 22 microdeletions ranging from 400 to 700 Kb produced a faint signal on the der(9); and the BCR-ABL DC/DF FISH pattern was comparable to the one obtained by the home brew probe in the presence of a 900-Kb chromosome 22 microdeletion. Our home-brew FISH system represents an accurate method for revealing a subset of CML patients with der(9) microdeletions.  相似文献   
77.
This article describes the Holistic Nursing: Scope and Standards of Practice. It defines holistic nursing, its five core values, and its practice standards. These include holistic philosophy, theory, and ethics; holistic caring process; holistic communication, therapeutic environment, and cultural diversity; holistic education and research; and holistic nurse self-care. Educational preparation for holistic nursing and settings in which holistic nurses practice are also explored.  相似文献   
78.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive death of cortical and spinal motor neurons, for which there is no effective treatment. Using a cell-based assay for compounds capable of preventing motor neuron cell death in vitro, a collection of approximately 40,000 low-molecular-weight compounds was screened to identify potential small-molecule therapeutics. We report the identification of cholest-4-en-3-one, oxime (TRO19622) as a potential drug candidate for the treatment of ALS. In vitro, TRO19622 promoted motor neuron survival in the absence of trophic support in a dose-dependent manner. In vivo, TRO19622 rescued motor neurons from axotomy-induced cell death in neonatal rats and promoted nerve regeneration following sciatic nerve crush in mice. In SOD1(G93A) transgenic mice, a model of familial ALS, TRO19622 treatment improved motor performance, delayed the onset of the clinical disease, and extended survival. TRO19622 bound directly to two components of the mitochondrial permeability transition pore: the voltage-dependent anion channel and the translocator protein 18 kDa (or peripheral benzodiazepine receptor), suggesting a potential mechanism for its neuroprotective activity. TRO19622 may have therapeutic potential for ALS and other motor neuron and neurodegenerative diseases.  相似文献   
79.
80.
Neurosurgical Review - Fedor Krause’s inspiring biography shows the value of translational thinking: one of the fathers of modern neurosurgery, this gifted child was recognized for his...  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