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   266162篇
  免费   19986篇
  国内免费   7063篇
耳鼻咽喉   1905篇
儿科学   4879篇
妇产科学   4778篇
基础医学   43680篇
口腔科学   4785篇
临床医学   18575篇
内科学   42527篇
皮肤病学   3563篇
神经病学   14863篇
特种医学   7608篇
外国民族医学   9篇
外科学   18627篇
综合类   33398篇
现状与发展   38篇
一般理论   25篇
预防医学   29517篇
眼科学   2965篇
药学   31532篇
  69篇
中国医学   13700篇
肿瘤学   16168篇
  2023年   3146篇
  2022年   4389篇
  2021年   9584篇
  2020年   8886篇
  2019年   8768篇
  2018年   8867篇
  2017年   9590篇
  2016年   9915篇
  2015年   9787篇
  2014年   12430篇
  2013年   18091篇
  2012年   13828篇
  2011年   16630篇
  2010年   11623篇
  2009年   11587篇
  2008年   13021篇
  2007年   14042篇
  2006年   13096篇
  2005年   11643篇
  2004年   10117篇
  2003年   9083篇
  2002年   7112篇
  2001年   6539篇
  2000年   5548篇
  1999年   4668篇
  1998年   3626篇
  1997年   3746篇
  1996年   3296篇
  1995年   3275篇
  1994年   3138篇
  1993年   2662篇
  1992年   2349篇
  1991年   2163篇
  1990年   1862篇
  1989年   1557篇
  1988年   1474篇
  1987年   1266篇
  1986年   1123篇
  1985年   1709篇
  1984年   1363篇
  1983年   989篇
  1982年   998篇
  1981年   831篇
  1980年   767篇
  1979年   635篇
  1978年   427篇
  1977年   353篇
  1976年   328篇
  1975年   222篇
  1974年   185篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
61.
IntroductionHip displacement is common in cerebral palsy (CP) and is related to the severity of neurological and functional impairment. It is a silent, but progressive disease, and can result in significant morbidity and decreased quality of life, if left untreated. The pathophysiology of hip displacement in CP is a combination of hip flexor-adductor muscle spasticity, abductor muscle weakness, and delayed weight-bearing, resulting in proximal femoral deformities and progressive acetabular dysplasia. Due to a lack of symptoms in the early stages of hip displacement, the diagnosis is easily missed. Awareness of this condition and regular surveillance by clinical examination and serial radiographs of the hips are the key to early diagnosis and treatment.Hip surveillance programmesSeveral population-based studies from around the world have demonstrated that universal hip surveillance in children with CP allows early detection of hip displacement and appropriate early intervention, with a resultant decrease in painful dislocations. Global hip surveillance models are based upon the patients’ age, functional level determined by the Gross Motor Function Classification system (GMFCS), gait classification, standardized clinical exam, and radiographic indices such as the migration percentage (MP), as critical indicators of progressive hip displacement.ConclusionDespite 25 years of evidence showing the efficacy of established hip surveillance programmes, there is poor awareness among healthcare professionals in India about the importance of regular hip surveillance in children with CP. There is a need for professional organizations to develop evidence-based guidelines for hip surveillance which are relevant to the Indian context.  相似文献   
62.
ABSTRACT

The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization.  相似文献   
63.
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
64.
65.
66.
Chile's October 2019 popular revolt has again made human rights violations visible in the context of mass mobilizations. In terms of damage to the population's health, multiple eye injuries produced by kinetic impact projectiles and tear bombs against people were reported, leading to an outbreak of unpublished eye injuries worldwide. There was excessive use of chemical weapons, and the totality of the chemicals used has not been transparent. The impact on mental health, especially of the population who lived during dictatorship in the 1970s, is uncertain and, health care was overwhelmed in the most vulnerable geographic areas. It is urgent to establish a timely and transparent system for monitoring such lesions and transparent all chemical compounds in tear-tearing and the composition of kinetic impact projectiles.  相似文献   
67.
68.
《Clinical neurophysiology》2021,132(2):315-322
ObjectivePrevious studies have demonstrated voluntary movement alterations as well as motor cortex excitability and plasticity changes in patients with mild cognitive impairment (MCI). To investigate the pathophysiology of movement abnormalities in MCI, we tested possible relationships between movement abnormalities and primary motor cortex alterations in patients.MethodsFourteen amnestic MCI (aMCI) patients and 16 healthy controls were studied. Cognitive assessment was performed using clinical scales. Finger tapping was recorded by a motion analysis system. Transcranial magnetic stimulation was used to test the input/output curve of motor evoked potentials, intracortical inhibition, and short-latency afferent inhibition. Primary motor cortex plasticity was probed by theta burst stimulation. We investigated correlations between movement abnormalities, clinical scores, and cortical neurophysiological parameters.ResultsMCI patients showed less rhythmic movement but no other movement abnormalities. Cortical excitability measures were normal in patients, whereas plasticity was reduced. Movement rhythm abnormalities correlated with frontal dysfunction scores.ConclusionOur study in MCI patients demonstrated abnormal voluntary movement and plasticity changes, with no correlation between the two. Altered rhythm correlated with frontal dysfunction.SignificanceOur results contribute to the understanding of pathophysiological mechanisms of motor impairment in MCI.  相似文献   
69.
The splanchnic anti-inflammatory pathway, the efferent arm of the endogenous inflammatory reflex, has been shown to suppress the acute inflammatory response of rats to systemic lipopolysaccharide (LPS). Here we show for the first time that this applies also to mice, and that the reflex may be engaged by a range of inflammatory stimuli. Experiments were performed on mice under deep anaesthesia. Half the animals were subjected to bilateral section of the splanchnic sympathetic nerves, to disconnect the splanchnic anti-inflammatory pathway, while the remainder underwent a sham operation. Mice were then challenged intravenously with one of three inflammatory stimuli: the toll-like receptor (TLR)-4 agonist, LPS (60 µg/kg), the TLR-3 agonist Polyinosinic:polycytidylic acid (Poly I:C, 1 mg/kg) or the TLR-2 and -6 agonist dipalmitoyl-S-glyceryl cysteine (Pam2cys, 34 µg/kg). Ninety minutes later, blood was sampled by cardiac puncture for serum cytokine analysis. The splanchnic anti-inflammatory reflex action was assessed by comparing cytokine levels between animals with cut versus those with intact splanchnic nerves. A consistent pattern emerged: Tumor necrosis factor (TNF) levels in response to all three challenges were raised by prior splanchnic nerve section, while levels of the anti-inflammatory cytokine interleukin 10 (IL-10) were reduced. The raised TNF:IL-10 ratio after splanchnic nerve section indicates an enhanced inflammatory state when the reflex is disabled. These findings show for the first time that the inflammatory reflex drives a coordinated anti-inflammatory action also in mice, and demonstrate that its anti-inflammatory action is engaged, in similar fashion, by inflammatory stimuli mimicking a range of bacterial and viral infections.  相似文献   
70.
SARS-CoV-2 (COVID-19) is highly-contagious. It can lead to respiratory distress—and in some cases—death. Recent reports and observations have identified an association between COVID-19 and manifestations in the feet. However, there are very few reports that describe the course of these foot manifestations in any detail. The authors present a case study chronicling the progression of foot issues in a COVID-19 positive patient who also was positive for the Epstein-Barr virus.  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