全文获取类型
收费全文 | 29390篇 |
免费 | 2449篇 |
国内免费 | 504篇 |
专业分类
耳鼻咽喉 | 489篇 |
儿科学 | 1169篇 |
妇产科学 | 487篇 |
基础医学 | 2419篇 |
口腔科学 | 1219篇 |
临床医学 | 3200篇 |
内科学 | 4713篇 |
皮肤病学 | 453篇 |
神经病学 | 7894篇 |
特种医学 | 633篇 |
外科学 | 1551篇 |
综合类 | 1998篇 |
现状与发展 | 3篇 |
一般理论 | 1篇 |
预防医学 | 3208篇 |
眼科学 | 205篇 |
药学 | 1931篇 |
7篇 | |
中国医学 | 440篇 |
肿瘤学 | 323篇 |
出版年
2024年 | 96篇 |
2023年 | 721篇 |
2022年 | 936篇 |
2021年 | 1578篇 |
2020年 | 1486篇 |
2019年 | 1441篇 |
2018年 | 1394篇 |
2017年 | 1319篇 |
2016年 | 1242篇 |
2015年 | 1105篇 |
2014年 | 1849篇 |
2013年 | 2741篇 |
2012年 | 1415篇 |
2011年 | 1700篇 |
2010年 | 1279篇 |
2009年 | 1364篇 |
2008年 | 1399篇 |
2007年 | 1263篇 |
2006年 | 1096篇 |
2005年 | 871篇 |
2004年 | 777篇 |
2003年 | 776篇 |
2002年 | 611篇 |
2001年 | 447篇 |
2000年 | 399篇 |
1999年 | 349篇 |
1998年 | 340篇 |
1997年 | 299篇 |
1996年 | 224篇 |
1995年 | 216篇 |
1994年 | 186篇 |
1993年 | 166篇 |
1992年 | 180篇 |
1991年 | 124篇 |
1990年 | 132篇 |
1989年 | 76篇 |
1988年 | 95篇 |
1987年 | 86篇 |
1986年 | 74篇 |
1985年 | 101篇 |
1984年 | 72篇 |
1983年 | 55篇 |
1982年 | 47篇 |
1981年 | 44篇 |
1980年 | 32篇 |
1979年 | 35篇 |
1978年 | 32篇 |
1977年 | 26篇 |
1976年 | 15篇 |
1975年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Sergio Starkstein Scott Gellar Morgan Parlier Leslie Payne Joseph Piven 《Journal of Neurodevelopmental Disorders》2015,7(1)
Background
While it is now recognized that autism spectrum disorder (ASD) is typically a life-long condition, there exist only a handful of systematic studies on middle-aged and older adults with this condition.Methods
We first performed a structured examination of parkinsonian motor signs in a hypothesis-generating, pilot study (study I) of 19 adults with ASD over 49 years of age. Observing high rates of parkinsonism in those off atypical neuroleptics (2/12, 17 %) in comparison to published population rates for Parkinson’s disease and parkinsonism, we examined a second sample of 37 adults with ASD, over 39 years of age, using a structured neurological assessment for parkinsonism.Results
Twelve of the 37 subjects (32 %) met the diagnostic criteria for parkinsonism; however, of these, 29 subjects were on atypical neuroleptics, complicating interpretation of the findings. Two of eight (25 %) subjects not taking atypical neuroleptic medications met the criteria for parkinsonism. Combining subjects who were not currently taking atypical neuroleptic medications, across both studies, we conservatively classified 4/20 (20 %) with parkinsonism.Conclusions
We find a high frequency of parkinsonism among ASD individuals older than 39 years. If high rates of parkinsonism and potentially Parkinson’s disease are confirmed in subsequent studies of ASD, this observation has important implications for understanding the neurobiology of autism and treatment of manifestations in older adults. Given the prevalence of autism in school-age children, the recognition of its life-long natural history, and the recognition of the aging of western societies, these findings also support the importance of further systematic study of other aspects of older adults with autism. 相似文献992.
993.
Background
Children are vulnerable to musculoskeletal injuries both at home and on the street for various reasons. Morbidity and disabilities resulting from these, mostly preventable, injuries, make them a burden to their families and society. The role of various factors associated with injuries is often not documented.Methods
This prospective study, done on 100 children aged up to 12 years with musculoskeletal trauma, analysed in details, the various modes of injuries.Results
One in every five patient was a child below 12 years of age. Boys were injured more than girls. Injuries, especially fractures, were most common in the extremities, the upper limb more commonly injured than the lower limb. Most of the injuries occurred at home. The most common mode of injuries was falls that happened while playing both within and outside the home, followed by road traffic accidents. Most injuries occurred during daytime.Conclusions
Injuries in children were found to be preventable. Small interventions while constructing homes can contribute tremendously to injury prevention and control in children. Parental awareness about the various modes of injury, role of supervised playing and their responsibility towards injury prevention can play a key role in reducing the morbidity associated with childhood fractures. 相似文献994.
Zheng Ke Hou Bo You Hui Yuan Jing Wang Haiyun Wang Ying Ye Wenling Qin Yan Song Dan Li Lei Chen Zhichun Zhu Lili Zhou Zijuan Yang Wei Zhao Haiyin Chen Limeng Zhu Yicheng Li Mingxi Cui Liying Feng Feng Li Xuemei. 《中华肾脏病杂志》2015,31(4):277-282
Objective To investigate cerebrovascular lesions on maintenance hemodialysis (MHD) patients, including types of cerebrovascular disease, and cognitive function changes. Methods A cross-sectional study was applied. A total of 270 MHD patients at hemodialysis center of Peking Union Medical College Hospital were screened, and finally 117 cases were enrolled. Demographic information, aboratory data, MRI and MRA data were collected and assessed. Cognitive function was evaluated with C - MMSE (Chinese mini mental test examination) and C - MoCA (Chinese montreal cognitive assessment). The related factors were selected by Spearman correlation analysis, multiple linear regression and logistic regression analysis. Results The patients’average age was (56.0± 12.5) years, average hemodialysis age was (73.5±60.8) months. Only 5.1% patients had clinical history of cerebral infarction or hemorrhage. Pre - hemodialysis blood pressure was (142.7/80.3±18.2/12.9) mmHg, Post-hemodialysis blood pressure was (130.2/79.1±23.4/14.9) mmHg. A total of 18.8% patients had intra-hemodialysis hypotension, spKt/V was (1.45±0.25). MR results showed that 12.0% patients had cerebral artery stenosis, 5.1% patients had cortical infarcts, 39.3% patients had lacunar infarcts, 47.0% patients had microbleeds, 7.7% patients had chronic hematoma, 52.1% patients had abnormal brain whiter matter lesions (WMLs). In cognitive function evaluation, 20.9% patients had abnormal C-MMSE scores, but 65.2% patients had abnormal C-MoCA results. Multiple linear regression showed age (b=0.059, P<0.01), dialysis age (b=0.005, P<0.05) were associated with WMLs in MHD patients. Intra-hemodialysis hypotension was an independent risk factor of lacunar infarcts (b=2.123, P<0.01) and microbleeds (b=3.531, P<0.01). Low serum albumin level was an independent risk factor of cognitive decline (b=0.314, P<0.05). Logistic regression analysis showed pre - hemodialysis systolic blood pressure was an independent risk factor of cortical infarcts [OR=1.088, 95%CI (1.018-1.152), P< 0.05]. Gender, dialysis age and pre - dialysis serum TCO2 level were related with chronic hematoma. Conclusions WMLs is related with dialysis voltage. Lacunar infarcts and mirobleeds are related with intra - hemodialysis hypotension. Lacunar infarcts, WMLs and nutritional status are contributed to decline of cognition in MHD patients. 相似文献
995.
Idilman R Colantoni A De Maria N Alkan S Nand S Van Thiel DH 《Journal of viral hepatitis》2004,11(4):302-309
Chronic hepatitis C virus (HCV) infection is associated with the development of lymphoproliferative disorders (LPDs). The aim of this investigation was to determine the prevalence and characterization of monoclonal gammopathy and benign and malignant LPDs in individuals with chronic hepatitis C. A total of 233 subjects diagnosed with chronic hepatitis C (male/female ratio: 131/102, median age; 49 years) were studied. Serum and urine were examined for the presence of a monoclonal gammopathy. A bone marrow aspirate and biopsy was obtained in individuals with a monoclonal gammopathy. Thirty-two patients (13.7%, 32 of 233) had a monoclonal gammopathy; 75% of them were benign and were not associated with malignant disorders (24 of 32) while 25% were associated with malignant LPDs or a plasma cell disorder (eight of 32). Two additional subjects without monoclonal gammopathy were diagnosed as having a malignant LPDs. The prevalence of malignant LPDs/plasma cell disorder in individuals with HCV-induced chronic liver disease was 4.3%. No difference was found in terms of disease duration, HCV genotype, viral load, alanine aminotransferase level or histopathologic score between the subjects with or without a monoclonal gammopathy. The presence of mixed cryoglobulinaemia was strongly associated with the presence of an underlying malignant disorder. Hence a monoclonal gammopathy is found in 14% of patients with chronic hepatitis C and is associated with malignant B-cell LPD in more than a quarter of such patients. The prevalence of LPDs in individuals with HCV-induced chronic liver disease is greater than that of the normal healthy population. 相似文献
996.
目的分析辽宁省大洼县碘缺乏病防治不同时期儿童智力水平。方法在碘缺乏病病区的3个乡4所学校和非病区的2个乡4所学校,以防治前、供应碘盐初期、全民食盐加碘后出生的7~14岁儿童为调查对象,用中国联合型瑞文测验图册(CRT—C)和农村儿童智商常模(CRT—RC2)测验儿童智商(IQ)。结果病区防治前、供应碘盐初期、全民食盐加碘后出生儿童智商分别为(97.4±14.8)、(99.3±14.6)、(107.9±14.3),IQ≤69者分别占4.8%、2.1%、1.1%;同时期非病区出生儿童智商分别为(103.1±14.4)、(103.2±14.5)、(112.1±14.2),IQ≤69者分别占1.4%、1.6%、1.0%;全民食盐加碘后病区、非病区儿童智商均高于相应地区防治前和供应碘盐初期(P〈0.01),而智力落后率则明显降低(P〈0.01)。结论全民食盐加碘后碘缺乏病病区与非病区出生儿童智力水平均有明显提高。 相似文献
997.
P. J. Roberts-Thomson M. Rischmueller R. A. Kwiatek M. Soden M. J. Ahern W. R. Hill R. A. Geddes 《Rheumatology international》1992,12(2):61-63
Summary Rheumatic manifestations are common and varied in infective endocarditis. We performed a retrospecitive case analysis on 87 patients with 93 episodes of infective endocarditis admitted to Flinders Medical Centre over an 11 year period (1980–1990). Disabling musculoskeletal symptoms and signs were documented in 22 (25%) of the patients. Thirteen patients developed severe or moderately severe low back pain during their illness, two with radiological evidence of a septic discitis or vertebral osteomyelitis. Two patients developed polyarthralgia/arthritis, four had septic arthritis (all with acute Staphylococcus aureus endocarditis), three developed severe loin pain, two acute gout, two had severe buttock pain and sacroiliac joint tenderness and two each developed disabling jaw/facial pain, neck/scapular pain and flank pain respectively. Five patients presented initially to the orthopaedic or rheumatological unit for management of their musculoskeletal symptoms. Four of seven patients with Streptococcus bovis endocarditis demonstrated prominent low back pain supporting a previously noted association between this organism and back symptoms. Furthermore, in one patient who had three separate episodes of endocarditis involving three different organisms, florid back symptoms were only seen in the infective episode involving Streptococcus bovis. 相似文献
998.
Circulating endothelial cells in vascular disorders: new insights into an old concept 总被引:19,自引:0,他引:19
The endothelial contribution to vascular disorders has been widely documented in experimental models. However, its implication in human pathology is difficult to investigate, owing to the paucity of noninvasive methods and of specific endothelial markers. The enumeration of circulating endothelial cells (CEC) released in peripheral blood after vascular injury represents a direct exploration of the endothelium. For this purpose, we have produced a monoclonal antibody (S-Endo 1), which recognizes CD 146, a molecule expressed on all types of human endothelial cells but absent from haemopoietic cells. Using this antibody, we have designed a specific and sensitive immunocapture test, which allowed us to detect high numbers of CEC in thrombotic, infectious or immunological disorders, while CEC were found to be very rare ( < 3/ml) in normal subjects. This quantitative approach using CEC might prove useful as a marker of vascular wall injury. Their enumeration is of interest in the clinical follow-up of vascular disorders, in the evaluation of therapeutic effectiveness or in the direct diagnosis of infectious diseases involving intra-endothelial microbial agents. Furthermore, an immunological and/or functional study of CEC could allow one to assess their procoagulant and proadhesive properties, as well as their viability, opening new perspectives for CEC investigation in vascular pathology. 相似文献
999.
Measurement of kinematic pharyngeal transit times, a new videofluoroscopy technique, provides useful quantitative data to supplement the qualitative data previously available from videofluoroscopy swallowing studies. Kinematic pharyngeal transit times have not previously been reported for subjects with myopathy. This study demonstrates the use of quantitative kinematic pharyngeal transit times for dysphagia evaluation in 15 patients with myopathy. The successful treatment of dysphagia by cricopharyngeal myotomy is reported in two patients with limb-girdle syndrome. 相似文献
1000.
Lynsey C. Patrott B. App Sc Sp.Path Wilfred G. Selley F.D.S. F. C. S. T. Hon Wendy A. Brooks B.Sc. Penny C. Lethbridge S.R.N. Jessica J. Cole M.C.S.P. Frederick C. Flack Ph.D. Richard E. Ellis M.Phil. John H. Tripp F.R.C.P. M.D. 《Dysphagia》1992,7(4):209-219
Eighteen children with cerebral palsy in a special school, most of whom had feeding difficulties, were studied to compare
the diagnostic value of the Exeter Dysphagia Assessment Technique (EDAT) with an exhaustive clinical assessment undertaken
by a multidisciplinary team experienced in the diagnosis and treatment of dysphagia of neurological origin. Four feeding skills
were assessed by each method independently, viz. anticipation, intraoral sensory perception, oral-motor efficiency, and pharyngeal
triggering. Comparison of the two sets of results showed agreement in at least 78% of the assessed skills. The possible reasons
for the few discrepancies are discussed. The noninvasive EDAT equipment was easy to use with the children, who had a range
of type and severity of cerebral palsy. The test was undertaken in their familiar surroundings and took 15 to 20 min per child.
Interpretation of the results showed that EDAT provided a rapid, reliable diagnostic aid which assisted in the assessment
of the degree of feeding impairment within each of the four feeding skills tested.
The authors are very grateful for the financial support for this project which was provided partially by Action Research and
partially by the Northcott Devon Medical Foundation 相似文献