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   5743篇
  免费   396篇
  国内免费   168篇
耳鼻咽喉   60篇
儿科学   223篇
妇产科学   135篇
基础医学   111篇
口腔科学   79篇
临床医学   1226篇
内科学   1237篇
皮肤病学   113篇
神经病学   341篇
特种医学   192篇
外科学   1684篇
综合类   11篇
预防医学   314篇
眼科学   325篇
药学   39篇
肿瘤学   217篇
  2023年   119篇
  2022年   43篇
  2021年   68篇
  2020年   96篇
  2019年   42篇
  2018年   126篇
  2017年   173篇
  2016年   182篇
  2015年   134篇
  2014年   220篇
  2013年   302篇
  2012年   92篇
  2011年   111篇
  2010年   227篇
  2009年   336篇
  2008年   116篇
  2007年   64篇
  2006年   102篇
  2005年   70篇
  2003年   45篇
  2002年   41篇
  2001年   108篇
  2000年   75篇
  1999年   138篇
  1998年   175篇
  1997年   203篇
  1996年   304篇
  1995年   256篇
  1994年   197篇
  1993年   115篇
  1992年   134篇
  1991年   144篇
  1990年   74篇
  1989年   129篇
  1988年   102篇
  1987年   79篇
  1986年   101篇
  1985年   83篇
  1984年   87篇
  1983年   74篇
  1982年   69篇
  1981年   63篇
  1980年   83篇
  1979年   43篇
  1978年   60篇
  1977年   42篇
  1976年   43篇
  1975年   48篇
  1964年   49篇
  1963年   47篇
排序方式: 共有6307条查询结果,搜索用时 15 毫秒
71.
Adenocarcinoma in situ (ACIS) of the uterine cervix is an increasingly recognized disease. Thirty-seven cases were reviewed to determine the effect of HPV, marital status, parity, smoking habit and age on the topography and behaviour of this lesion. Using a commercial probe, 25% of 28 lesions tested were positive for HPV 16/18. The presence of HPV and a history of smoking appeared to exert no significant influence upon the topography and behaviour of ACIS. Nulliparity and a history of never being married was associated with a significant reduction in the incidence of coexisting CIN lesions. Age less than 36 years was associated with a significant reduction in the proximal linear extent of ACIS. While hysterectomy is probably the definitive treatment for ACIS of the cervix, there is an important place for conservative management by conization alone. Patients younger than 36 years are most likely to be desirous of retained fertility and appear to have the lesions most amenable to conservative surgery.  相似文献   
72.
Presacral Neurectomy - A Reappraisal   总被引:1,自引:0,他引:1  
Between April 1984 and April 1990, 20 patients with a mean age of 27.9 years underwent presacral neurectomy at The Royal Women's Hospital, Melbourne, Australia. Overall, 11 of the 19 patients (58%) assessable for follow-up were totally cured of pain and 8 (42%) were partially cured. The most common indication for presacral neurectomy was secondary dysmenorrhoea, usually in association with endometriosis or pelvic adhesions. In 4 patients with uterine dysmenorrhoea not associated with pelvic pathology the operation produced a complete cure. The general consensus of gynaecological opinion is that presacral neurectomy should still be reserved for a limited number of carefully selected patients in whom other methods of treatment have been exhausted. It is imperative that a prior psychological assessment should be undertaken whenever a functional component is suspected. Whilst pain of uterine origin may be cured by presacral neurectomy, lateral pelvic pain of adnexal origin requires ovarian sympathectomy.  相似文献   
73.
The coagulation system of the newborn infant shows some functional impairment during the first few days of life. While these abnormalities are transient and can probably be regarded as ‘physiological’ in some babies, others, especially those who are breast fed, are at risk of suffering life-threatening haemorrhage. There is good evidence that, in at least some newborn babies, the coagulation abnormalities may be corrected by giving vitamin K. Although occasional serious accidents have resulted from the practice of administering intramuscular vitamin K in the delivery room, no fatalities have been reported in the recent literature. The preparation of vitamin K in current use appears to have no side effects when given intraumscularly or orally to newborn infants. Since the majority of newborn babies in most hospitals in this country are breast fed for at least the first few days of life it would seem appropriate for prophylactic vitamin K to be given either to all newborn infants soon after birth or to those at increased risk of developing HDN. Administration by mouth is probably safer than by intramuscular injection but more detailed research is needed to establish the efficacy and optimal dosage for the oral route. The requirement for vitamin K beyond the first few days of life has not been defined and objective recommendations concerning the prevention of late-onset haemorrhagic disease must await the results of further studies.  相似文献   
74.
Abstract Twenty-two individuals with Prader-Willi Syndrome in New South Wales were surveyed. The results show that males were diagnosed at a significantly earlier age than females and suggest a recent trend towards earlier diagnosis. The advantages of early diagnosis are discussed. In those in whom cytogenetic studies had been performed, 47% were found to have a deletion involving chromosome 15q11–13. Profound neonatal hypotonia had been present in all cases. Obesity became apparent between 1.5 and 10 years (mean = 3.8 years). Facial dysmorphism was reported in 83% and acromicria in 100%. Sixty-two per cent of subjects were regarded as less pigmented than first degree relatives. Cognitive assessments were performed on nine subjects. Two (22%) were functioning in the normal range of intelligence. Behaviour problems, both food-related and non-food-related, were present in the majority and placed considerable stress on the family caring for the individual with Prader-Willi Syndrome.  相似文献   
75.
Abstract A double-blind crossover study was performed on 33 children with asthma to compare the effectiveness of nebulized solutions of preservative-containing and preservative-free ipratropium bromide. Both solutions produced bronchodilation. No significant differences were found between the two solutions at any time after nebulization in minimum and maximum changes from baseline value or in the areas under the lung function time curves. The presently formulated preservative-containing ipratropium bromide solution was not shown to be inferior to a preservative-free compound.  相似文献   
76.
C. B. CHOW  MB  BS  MCRP  DCH.  P. S. WANG  MB  BS  MRCP  DCH  N. K. LEUNG  MB  BS  FRCP  DCH. 《Journal of paediatrics and child health》1989,25(3):147-150
Abstract Experience with typhoid fever in 111 children over a 5-year period was reviewed. There were 66 boys and 45 girls, ranging in age from 1 to 11.5 years. The symptoms of typhoid fever were quite non-specific. Fever was the most common presenting symptom (in 98.3%). Other common presenting features were diarrhoea (25.7%), constipation (22%), vomiting (21.1%), cough (25%), abdominal pain (27.5%), headache (9.2%), epistaxis, meningism and convulsions. Rose spots were detected in 20% of cases, occurring mainly during the first 2 weeks of illness. Significant Widal reactions were present in 84.7% of cases. Blood and stool cultures were positive in 57% and 44% of cases, respectively. Peripheral blood white cell counts were not found to be of great diagnostic value. Chloramphenicol remained the drug of choice in the treatment of typhoid fever. It was more effective than ampicillin or co-trimoxazole. Complications were uncommon, occurring in only two patients. There were two deaths; both were admitted late and in moribund state. Early diagnosis and treatment is vital in typhoid fever and, as the presenting features are non-specific, a high index of suspicion is required.  相似文献   
77.
Abstract A 6 year old child is described with infection due to herpes simplex virus type 1 causing brain stem encephalitis. The diagnosis was established by enzyme immunosorbent assays of the cerebrospinal fluid and serum which demonstrated antibody responses to herpes simplex virus. Recovery occurred and the importance of early use of acyclovir in achieving a good outcome is emphasized.  相似文献   
78.
The authors determined the results after traction or traction and hip spica treatment of the initial fractures through unicameral bone cysts of the proximal femur in 20 children. All of the eight displaced fractures healed, but with coxa vara and avascular necrosis in one, coxa vara in a second, and coxa breva in a third. Spontaneous healing of the cyst occurred in three of the eight children; satisfactory healing was achieved and maintained after intralesional corticosteroid injections in four of the eight children. In the remaining child with a displaced fracture, reactivation of the cyst and exercise-related pain, indicative of an incipient refracture, occurred 3 years after initial presentation. All of the 12 undisplaced fractures healed without deformity or avascular necrosis. Intralesional corticosteroids were used in all of the 12 children because none of them showed spontaneous healing of their cysts. Satisfactory radiographic healing was achieved 1 year after presentation in all of the 12 children. However, one or more refractures resulting from reactivation of the cyst occurred in 6 of the 12 children 2 to 5 years after initial presentation. The results of this study indicate that satisfactory radiographic healing needs to be achieved by the end of the first year and needs to be maintained thereafter to prevent refractures.  相似文献   
79.
80.
A mathematical model for predicting the growth response in patients with Turner syndrome who received growth hormone (GH) therapy was developed by analysing data from KIGS, the Pharmacia & Upjohn International Growth Database. A Model for year 1 of GH therapy explained 46% of the variability of the growth response, with GH dose being the most important of the predictors of height velocity. In years 2-4 of therapy, height velocity during the previous year was the most important predictor, suggesting that an individual's initial response to GH may determine the height outcome of treatment. Additional treatment with oxandrolone. The predictions in all 4 years were highly accurate, as indicated by the low error SDs. However, relatively low predictive power ( R ) during years 2-4 of treatment suggests the models are missing other parameters that would explain more of the variability of the growth response. These growth prediction models could help clinicians to design individualized treatment regimens, provide realistic expectations of therapy outcomes, and adjust treatment on the basis of detected differences between observed and predicted height velocities.  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