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   1640432篇
  免费   134106篇
  国内免费   3501篇
耳鼻咽喉   21966篇
儿科学   53892篇
妇产科学   47244篇
基础医学   231982篇
口腔科学   47849篇
临床医学   144468篇
内科学   323631篇
皮肤病学   34702篇
神经病学   133609篇
特种医学   66094篇
外国民族医学   476篇
外科学   248957篇
综合类   41774篇
现状与发展   4篇
一般理论   545篇
预防医学   124983篇
眼科学   37015篇
药学   124565篇
  11篇
中国医学   3921篇
肿瘤学   90351篇
  2018年   15893篇
  2016年   13886篇
  2015年   16307篇
  2014年   22289篇
  2013年   33328篇
  2012年   45109篇
  2011年   47336篇
  2010年   27904篇
  2009年   26763篇
  2008年   45147篇
  2007年   47388篇
  2006年   48026篇
  2005年   46520篇
  2004年   45788篇
  2003年   43615篇
  2002年   42566篇
  2001年   76654篇
  2000年   79260篇
  1999年   67239篇
  1998年   18081篇
  1997年   16609篇
  1996年   16594篇
  1995年   16236篇
  1994年   15275篇
  1993年   14379篇
  1992年   55878篇
  1991年   54152篇
  1990年   52920篇
  1989年   51205篇
  1988年   47514篇
  1987年   46833篇
  1986年   44555篇
  1985年   43076篇
  1984年   32231篇
  1983年   27713篇
  1982年   16234篇
  1981年   14502篇
  1980年   13634篇
  1979年   30615篇
  1978年   21154篇
  1977年   17846篇
  1976年   16758篇
  1975年   17636篇
  1974年   21580篇
  1973年   20773篇
  1972年   18945篇
  1971年   17849篇
  1970年   16360篇
  1969年   15341篇
  1968年   14006篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
INTRODUCTION: Autoimmune hepatitis (AIH) is a well-defined entity in the West but there are sparse Indian data on this disease. AIM: To study the clinical profile and response to treatment of Indian patients with AIH. METHODS: This is a part retrospective and part prospective study of 50 patients (median age 48 years, range 11-82; 43 women) seen between 1995 to 2001, diagnosed to have AIH as per the revised scoring system. Clinical and laboratory profile, response to treatment, and complications of treatment were analyzed. RESULTS: AIH accounted for 6% of all patients with liver disease seen during the period. The presenting symptoms were gastrointestinal in 43 and non-gastrointestinal in 7, with median symptom duration of 6 months (range 2 weeks to 40 years). Forty patients (80%) had chronic liver disease. Associated illnesses were present in 28 patients. Twenty-six patients were classified as definite and the rest as probable AIH. Forty-nine patients had Type 1 AIH. Five patients had overlap syndrome. Forty-five patients (90%) received immunosuppressive therapy. Twelve of 18 patients receiving only prednisolone and 21 of 27 patients receiving prednisolone and azathioprine combination responded. Thirteen (26%) patients had therapy-related complications (infectious 5, non infectious 8) with two treatment-related deaths. CONCLUSION: Type 1 AIH was the predominant type of AIH. The majority of patients with AIH presented with chronic liver disease. There was good response to immunosuppressive therapy. Therapy-related complications occurred in one-fourth of patients.  相似文献   
92.
The aim of the present study was to explore differences in the clinical expression, clinical diagnoses and management of airway diseases in a primary-care setting. Patients aged >or=35 yrs who had ever smoked were enrolled when they presented for any reason to one of eight rural primary-care practices. Respiratory symptom questionnaires and spirometry were administered. In total, 1,034 patients had acceptable and reproducible spirometry, of whom 550 (53%) were males and 484 (47%) were females. Males smoked more than females (41.2 versus 29.2 pack-yrs) respectively, and were more likely to have a pre-bronchodilator forced expiratory volume in one second/forced vital capacity <0.70 at 22.4 versus 11.8%, respectively. However, more females than males reported breathlessness (51.0 versus 42.8%, respectively), a prior diagnosis compatible with airflow obstruction and taking respiratory medications (23.4 versus 14.9%, respectively). In conclusion, the current results suggest that females are more likely than males to report breathlessness and be prescribed respiratory medications independent of differences in the severity of airflow obstruction.  相似文献   
93.
94.
95.
96.
97.
We report a case of cervical necrotizing fasciitis (CNF) in a female having uncontrolled type II diabetes mellitus. The patient was presented to us after 20 days of preliminary symptoms. The aetiology of microbial inoculation in subdermal tissue was not known. The isolate was Staphylococcus aureus. In spite of the delay in presentation, the patient was successfully treated with combined antimicrobial and surgical intervention.  相似文献   
98.
Clinicopathological and electron microscopical findings of eight cases of enzootic nasal adenocarcinoma of sheep, diagnosed solely in one big flock in Slovenia between years 2001 and 2003 are described. All affected sheep were female, their mean age was 4.5 ± 1.5 years and they either belonged to the Istrian pramenka breed (five sheep) or were crossbreeds (three sheep). Tumours that arose from the ethmoid area of the nasal cavity were unilateral in six cases (75%) and bilateral in two cases (25%). All tumours were classified as adenocarcinomas by histopathological examination and they displayed either a combination of tubular and papillary growth or less often solely tubular proliferation. No metastases were detected in regional lymph nodes, brain or other organs. Electron microscopical studies performed on the reprocessed paraffin‐embedded tissues revealed the presence of the virus‐like particles with an average diameter between 70 and 90 nm.  相似文献   
99.
The influence of short‐term confinement and moderate exercise on tibia development was investigated in growing pigs (36–41 kg, 10 weeks at the beginning of the study). Animals were kept for 2 weeks either in individual crates of 0.8 m2 (‘confinement’, n = 4) or kept in groups of four animals in large crates of 5.6 m2 without (‘control’) or with additional exercise (30 min walking at 5 days/week; ‘exercise’). Bone density and morphological parameters were evaluated by computer tomography (CT). Periosteal apposition and longitudinal growth were determined after polychrome sequential labelling in weekly intervals. Cortical areas of the cross sections at the mid‐shaft and at 75% of the length of the bone measured distal to the carpus by CT were significantly correlated to each other (r = 0.70) and revealed a significant reduction in confined animals. This difference was explained by lower periosteal apposition rates in these animals compared with exercised and group‐housed pigs. Similarly longitudinal growth and the formation and calcification of spongiosa of the tibiae were inhibited by confinement. Thus, 2 weeks of confinement led to significant differences in bone growth and metabolism in young growing piglets when compared with animals with moderate activity.  相似文献   
100.
A 72-year-old man presented with a short duration of symptoms relating to a right fronto-parietal glioblastoma and a family history of children with brain tumours. Analysis of the patient's family tree revealed that out of seven children, he had a living son with anaplastic astrocytoma, a daughter who had died with a glioblastoma, and a son who had died with a histologically undiagnosed intrinsic brain tumour. One niece was also thought to have died from a brain tumour. All of the other affected family members had onset in their third or fourth decades. Tissue was only available from two of the affected individuals, precluding familial genetic analysis at this stage. There is no clinical evidence to support a diagnosis of a multiple cancer or neurocutaneous syndrome in this family. In view of what is known about the genetics of familial glioma, it is interesting to note the clinical evidence of both 'primary' glioblastoma and anaplastic astrocytoma in the same kindred.  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