全文获取类型
收费全文 | 1329篇 |
免费 | 59篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 62篇 |
妇产科学 | 19篇 |
基础医学 | 113篇 |
口腔科学 | 42篇 |
临床医学 | 123篇 |
内科学 | 361篇 |
皮肤病学 | 109篇 |
神经病学 | 34篇 |
特种医学 | 207篇 |
外科学 | 125篇 |
综合类 | 30篇 |
预防医学 | 77篇 |
眼科学 | 7篇 |
药学 | 36篇 |
中国医学 | 3篇 |
肿瘤学 | 46篇 |
出版年
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 8篇 |
2017年 | 14篇 |
2016年 | 18篇 |
2015年 | 22篇 |
2014年 | 25篇 |
2013年 | 67篇 |
2012年 | 17篇 |
2011年 | 16篇 |
2010年 | 49篇 |
2009年 | 57篇 |
2008年 | 23篇 |
2007年 | 30篇 |
2006年 | 28篇 |
2005年 | 34篇 |
2004年 | 16篇 |
2003年 | 15篇 |
2002年 | 22篇 |
2001年 | 22篇 |
2000年 | 12篇 |
1999年 | 20篇 |
1998年 | 83篇 |
1997年 | 72篇 |
1996年 | 76篇 |
1995年 | 49篇 |
1994年 | 62篇 |
1993年 | 51篇 |
1992年 | 17篇 |
1991年 | 15篇 |
1990年 | 21篇 |
1989年 | 41篇 |
1988年 | 42篇 |
1987年 | 32篇 |
1986年 | 26篇 |
1985年 | 26篇 |
1984年 | 23篇 |
1983年 | 12篇 |
1982年 | 21篇 |
1981年 | 18篇 |
1980年 | 13篇 |
1979年 | 17篇 |
1978年 | 14篇 |
1977年 | 16篇 |
1976年 | 16篇 |
1975年 | 12篇 |
1973年 | 14篇 |
1972年 | 9篇 |
1971年 | 7篇 |
1957年 | 7篇 |
排序方式: 共有1421条查询结果,搜索用时 62 毫秒
81.
SF Slaney AO Wilkie MC Hirst R Charlton M McKinley J Pointon Z Christodoulou SM Huson KE Davies 《Archives of disease in childhood》1995,72(1):33-37
Fragile X syndrome is the most common inherited cause of mental retardation. Early diagnosis is important not only for appropriate management of individuals but also to identify carriers who are unaware of their high risk of having an affected child. The disorder is associated with a cytogenetically visible fragile site (FRAXA) at Xq27.3, caused by amplification of a (CGG)n repeat sequence within the gene at this locus designated FMR1. Clinical and molecular studies have been undertaken to screen for fragile X syndrome in 154 children with moderate and severe learning difficulties of previously unknown origin. Southern blot analysis of peripheral blood showed the characteristic abnormally large (CGG)n repeat sequence associated with fragile X syndrome in four of the 154 children. The findings were confirmed by cytogenetic observation of the fragile site and by further molecular studies. The families of the affected children were offered genetic counselling and DNA tests to determine their carrier status. These findings show that there are still unrecognised cases of fragile X syndrome. Given the difficulty of making a clinical diagnosis and the implications for families when the diagnosis is missed, screening in high risk populations may be justified. The issues involved in screening all children in special schools for fragile X syndrome are discussed. 相似文献
82.
Colostrum protects the newborn from intestinal infection by its content of secretory immunoglobulin A and other immediately acting factors. It may also induce maturation of the child's gastrointestinal immune defences, thus contributing to the protection against diarrhoeal disease later in infancy. To test this hypothesis, a case–control study on breast feeding and diarrhoea was carried out in a periurban community in Guinea–Bissau. The child's age at the start of breast feeding was ascertained soon after birth ( n = 279). Subsequent cases of acute diarrhoea ( n = 66) were identified at 3–monthly examinations, and four concurrent controls were randomly selected among attendants. Three separate estimates of association showed that the cases tended to have started breast feeding later after birth than the diarrhoea–free controls, but no single test was statistically significant. Early breast feeding might have consequences for diarrhoeal morbidity after the neonatal period. 相似文献
83.
84.
85.
86.
RM Subramaniam J Sherriff K Holmes MC Chan B Shadbolt 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):442-446
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups. 相似文献
87.
Aberrant Notch signalling has been observed in several human cancers, including acute T-cell lymphoblastic leukaemia and cervical cancer, and is strongly implicated in tumourigenesis. Unregulated Notch signalling in the mouse mammary gland leads to tumour formation. These results raise the possibility that Notch signalling might play a role in human breast cancer. There are currently few reports that address this question directly and this appears to be an area worthy of further investigation. 相似文献
88.
89.
Italian multicentre study on very low-birth-weight babies. Neonatal mortality and two-year outcome 总被引:1,自引:0,他引:1
U de Vonderweid A Spagnolo C Corchia V Chiandotto S Chiappe F Chiappe P Colarizi TDe Luca M Didato MC Fertz F Macagno G Mansi R Paludetto A Priolisi A Spinelli P Zaramella C Zorzi 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(4):391-396
The Italian multicentre study on very low-birth-weight babies is the first collaborative project in Italy on the health status of newborns weighing 500–1499 g at birth: 634 such babies were admitted in 1987–88 to eight Italian NICUs; 424 infants survived and were followed until two years of age, corrected for prematurity. Logistic regression analysis of pre-admission risk factors of in-hospital mortality identified eight statistically significant variables: birth weight, gestational age, sex, antepartum steroids, I-min Apgar score and, on admission to the NICU, body temperature, pH and absence of spontaneous respiration. Using the equation derived from the logistic model, a theoretical mortality rate was calculated for each centre, predicted on the basis of the local incidence of preadmission risk factors. In no case was the predicted mortality significantly different from the observed one. At two years of age, 8 children were blind and 48 had motor disability. Of these, 46 had cerebral palsy: based on a functional evaluation score 14 had severe (degree 4), 20 intermediate (degree 3) and 12 mild cerebral palsy (degree 2). Among 25 variables entered in a logistic regression as risk factors for cerebral palsy, only periventricular leucomalacia and acidosis were significantly associated with the outcome. 相似文献
90.