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   1630篇
  免费   141篇
  国内免费   46篇
耳鼻咽喉   15篇
儿科学   110篇
妇产科学   52篇
基础医学   147篇
口腔科学   39篇
临床医学   204篇
内科学   319篇
皮肤病学   136篇
神经病学   81篇
特种医学   183篇
外科学   151篇
综合类   30篇
预防医学   86篇
眼科学   20篇
药学   99篇
  1篇
中国医学   9篇
肿瘤学   135篇
  2023年   3篇
  2021年   12篇
  2020年   15篇
  2019年   17篇
  2018年   29篇
  2017年   33篇
  2016年   35篇
  2015年   43篇
  2014年   51篇
  2013年   66篇
  2012年   38篇
  2011年   62篇
  2010年   60篇
  2009年   85篇
  2008年   59篇
  2007年   86篇
  2006年   45篇
  2005年   59篇
  2004年   46篇
  2003年   36篇
  2002年   39篇
  2001年   45篇
  2000年   51篇
  1999年   45篇
  1998年   83篇
  1997年   95篇
  1996年   67篇
  1995年   60篇
  1994年   43篇
  1993年   50篇
  1992年   33篇
  1991年   27篇
  1990年   27篇
  1989年   43篇
  1988年   30篇
  1987年   40篇
  1986年   27篇
  1985年   23篇
  1984年   12篇
  1983年   14篇
  1982年   10篇
  1981年   10篇
  1980年   12篇
  1979年   4篇
  1978年   6篇
  1977年   12篇
  1976年   6篇
  1943年   2篇
  1931年   2篇
  1930年   2篇
排序方式: 共有1817条查询结果,搜索用时 15 毫秒
991.
A 13-year-old girl presented with a recurring vulval dermatitis that started several days after first using a sanitary pad. The rash settled but recurred with subsequent use of the same sanitary pads. Patch testing revealed a marked sensitivity (3+) to colophony (rosin). She denied previous reactions to adhesive tape/sticking plaster. During patch testing she also developed reactions to a black permanent waterproof marking pen used to mark the site of patch tests. The ink of this pen also contained colophony.  相似文献   
992.
Injuries of the peroneus tendons are common and both the athlete and the older population are at risk. MR imaging is a useful technique for revealing injuries of the peroneus tendons as well as showing anatomic factors associated with these lesions. This article reviews clinical factors and MR imaging characteristics of injuries of the peroneus tendons.  相似文献   
993.
BACKGROUND: In patients with early-stage breast cancer, 5 years of treatment with the selective estrogen receptor modulator (SERM) tamoxifen reduces breast cancer recurrence and mortality, whereas more than 5 years of tamoxifen does not further reduce breast cancer recurrence and doubles the risk of endometrial cancer. We evaluated the effects on tumor growth of raloxifene, another SERM, after tamoxifen treatment in mouse models of breast and endometrial cancers. METHODS: Athymic, ovariectomized mice were bitransplanted with tumors derived from human breast cancer and endometrial cancer cells that either were tamoxifen-naive or had been exposed to tamoxifen for short (6 months) or long (>5 years) terms. The effects of raloxifene (two dose levels) and tamoxifen on tumor growth in the presence and absence of low-dose estrogen were evaluated. All statistical tests were two-sided. RESULTS: Raloxifene was less effective than tamoxifen in blocking the stimulatory effects of low-dose estrogen on the growth of tamoxifen-naive breast (P<.001) and endometrial (P =.001) tumors. Raloxifene and tamoxifen had similar inhibitory effects on the growth of short-term tamoxifen-exposed breast tumors. Raloxifene and tamoxifen had similar stimulatory effects on the growth of breast and endometrial tumors that had been exposed to at least 5 years of tamoxifen. However, neither drug blocked the stimulatory effects of estrogen on the growth of these tumors. Raloxifene was less effective than tamoxifen (P<.001) in blocking the stimulatory effects of estrogen on endometrial tumors that had been exposed to tamoxifen in the past. CONCLUSIONS: Raloxifene and tamoxifen had similar effects on these mouse models of tamoxifen-naive and tamoxifen-resistant breast and endometrial cancer. Treatment with raloxifene following 5 years of adjuvant tamoxifen may not further decrease breast cancer recurrence and may increase endometrial cancer incidence.  相似文献   
994.
Abstract A numeric scoring system for the assessment of hypoxic ischaemic encephalopathy during the neonatal period was tested. The value of the score in predicting neurodevelopmental outcome at 1 y of age was assessed. Forty-five infants who developed hypoxic ischaemic encephalopathy after birth were studied prospectively. In addition to the hypoxic ischaemic encephalopathy score all but two infants had at least one cranial ultrasound examination. Thirty-five infants were evaluated at 12 months of age by full neurological examination and the Griffiths Scales of Mental Development. Five infants were assessed at an earlier stage, four who died before 6 months of age and one infant who was hospitalized at the time of the 12 month assessment. Twenty-three (58%) of the infants were normal and 17 (42%) were abnormal, 16 with cerebral palsy and one with developmental delay. The hypoxic ischaemic encephalopathy score was highly predictive for outcome. The best correlation with outcome was the peak score; a peak score of 15 or higher had a positive predictive value of 92% and a negative predictive value of 82% for abnormal outcome, with a sensitivity and specificity of 71% and 96%, respectively. For the clinician working in areas where sophisticated technology is unavailable this scoring system will be useful for assessment of infants with hypoxic ischaemic encephalopathy and for prognosis of neurodevelopmental outcome.  相似文献   
995.
A review of open biopsy for mediastinal masses   总被引:2,自引:0,他引:2  
Objective: To review the recent experience with biopsied mediastinal lesions in children and to assess the impact of recent advances in imaging and surgical techniques on diagnosis. Methodology: The clinical and radiological features of 55 patients who had mediastinal biopsies at The Royal Alexandra Hospital For Children (RAHC) over 15 years were reviewed. Results: Fifty-five patients presented to RAHC between 1978 and 1993 with lesions of the mediastinum requiring biopsy of that site. Thirty-one of the 55 (56%) lesions were malignant. Neurogenic tumours were the most common (40%). In order of frequency the following lesions were found: neuroblastoma (15), teratoma (eight), non- Hodgkin's lymphoma (NHL; eight), enteric cyst/duplication (five), ganglioneuroma (five), bronchogenic cyst (three), ganglioneuroblastoma (two), lymphangioma (two), abscess (two), Hodgkin's lymphoma (HL; two), oesophageal granuloma (one), Langerhan's cell histiocytosis (one), congenital fibromatosis (one). Eighty-two per cent of neurogenic tumours were located in the posterior mediastinum, while 75% of teratomas and 100% lymphoid tumours were located anteriorly. Symptoms were generally unhelpful in establishing a specific diagnosis and in 27% of cases the lesions were discovered incidentally. Physical signs, such as thoracic inlet obstruction and neurological findings, were helpful clinically in localizing lesions within the mediastinum. Chest radiography enabled lesions to be subdivided within the mediastinum. This localization, in combination with the age at presentation, predicted the tissue diagnosis. Computerized tomography (CT) and magnetic resonance imaging (MRI) further defined the lesion and demonstrated involvement of adjacent structures. Histology, however, was essential to distinguish benign from malignant lesions. Conclusions: The clinical presentation of mediastinal masses is often non-specific or incidental. Despite recent advances in imaging technology and biopsy techniques, full histological examination is required to exclude malignancy.  相似文献   
996.
Nasopharyngeal carcinoma is a common cancer in South East Asia. In the early stages, radiotherapy alone may achieve sustained control, but once metastasis occurs, it becomes an incurable disease with limited survival time. We report a case of nasopharyngeal carcinoma, initial stage T4N0M0, diagnosed in 1985 in a patient aged 36 years who received 70 Gy radiotherapy to the head and neck region. In 1988, relapse occurred with multiple lung metastases. The patient received many chemotherapy regimens with a very good response, including near complete remission with the first treatment regimen of cisplatin, 5-fluorouracil and leucovorin for lung metastases, and with the fifth chemotherapy regimen of ifosfamide as a single agent. After ifosfamide treatment, there was residual fibrotic change in the lung and complete disappearance, lasting for almost a year, of the liver and bone lesions. The patient eventually died in July 1995 due to progressive disease. Prolonged survival after mainly thoracic metastasis is possible in patients with nasopharyngeal carcinoma, especially if the tumor is chemo-responsive.   相似文献   
997.
子宫腔纱条填塞术在控制剖宫产出血中的应用   总被引:59,自引:0,他引:59  
子宫腔纱条填塞术在控制剖宫产出血中的应用胡娅莉周重宛金溶溶罗月娥李文玉产后出血是剖宫产最常见的并发症。我科自1989年始应用宫腔纱条填塞控制剖宫产术中严重子宫出血,取得满意效果,报告如下。一、临床资料1.一般情况:1989年1月~1996年12月本院...  相似文献   
998.
999.
OBJECTIVE: To evaluate the efficacy and toxicity of a regimen of etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine in patients with metastatic, high-risk gestational trophoblastic tumors. METHODS: Twelve women with metastatic gestational choriocarcinoma received 64 treatment cycles. All met the National Cancer Institute criteria for high-risk gestational trophoblastic tumors. Response was evaluated by monitoring serial serum beta-hCG levels. Toxicity was recorded using standard World Health Organization criteria. RESULTS: There was no life-threatening toxicity. Neutropenia necessitating a 1-week delay of treatment occurred with only eight treatment cycles (12.5%) and deferral of vincristine and cyclophosphamide with three cycles. Anemia requiring transfusion complicated only two cycles. Peripheral neuropathy in two patients was treated by discontinuing vincristine. Other toxicities included nausea and vomiting, diarrhea, stomatitis, alopecia, conjunctivitis, thrombocytopenia, and fever. Ten of the 12 subjects experienced a complete response. Two had partial responses and one with an initial complete response had relapse 4 months after completing therapy; all three were successfully salvaged with cisplatin-based chemotherapy. Overall survival was 100%, and all 12 patients are disease-free with a median follow-up of 26 months. CONCLUSIONS: Chemotherapy with etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine is well tolerated and highly effective for metastatic, high-risk gestational trophoblastic disease.  相似文献   
1000.
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