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   339篇
  免费   16篇
  国内免费   13篇
儿科学   34篇
妇产科学   3篇
基础医学   41篇
口腔科学   12篇
临床医学   32篇
内科学   64篇
皮肤病学   7篇
神经病学   6篇
特种医学   93篇
外科学   18篇
综合类   4篇
预防医学   9篇
眼科学   11篇
药学   14篇
肿瘤学   20篇
  2022年   2篇
  2021年   3篇
  2020年   1篇
  2019年   2篇
  2018年   3篇
  2017年   4篇
  2016年   3篇
  2015年   12篇
  2014年   5篇
  2013年   9篇
  2012年   8篇
  2011年   2篇
  2010年   17篇
  2009年   10篇
  2008年   4篇
  2007年   12篇
  2006年   7篇
  2005年   9篇
  2004年   6篇
  2003年   4篇
  2002年   6篇
  2001年   2篇
  2000年   18篇
  1999年   5篇
  1998年   25篇
  1997年   39篇
  1996年   27篇
  1995年   18篇
  1994年   14篇
  1993年   6篇
  1992年   4篇
  1991年   1篇
  1990年   4篇
  1989年   11篇
  1988年   10篇
  1987年   1篇
  1986年   6篇
  1985年   5篇
  1984年   2篇
  1983年   10篇
  1982年   5篇
  1981年   3篇
  1980年   5篇
  1979年   1篇
  1978年   2篇
  1977年   7篇
  1976年   4篇
  1975年   3篇
  1973年   1篇
排序方式: 共有368条查询结果,搜索用时 15 毫秒
31.
32.
The myeloid zinc finger gene, MZF-1, regulates the CD34 promoter in vitro   总被引:2,自引:1,他引:2  
Morris  JF; Rauscher  FJ rd; Davis  B; Klemsz  M; Xu  D; Tenen  D; Hromas  R 《Blood》1995,86(10):3640-3647
  相似文献   
33.
The early clinical experience with a 3-Dimensional Fourier Transform Gradient Echo sequence with fat suppression in the evaluation of breast masses is reported. Ten female patients with breast malignancies were pre-operatively evaluated with this sequence and the results compared with the pathological specimens. The scanning protocol included a noncontrast sequence followed by an immediate post-contrast sequence (completed 4.5 min after intravenous contrast injection) and a delayed sequence. Images were assessed for maximum lesion and parenchymal enhancement, lesion size and additional enhancing abnormalities. In six patients, malignant masses enhanced maximally on the immediate post-contrast sequence with parenchyma enhancing maximally on delayed images. In three cases, there was preferential enhancement of malignant lesions over normal parenchyma but to a similar degree on both post-contrast sequences. In one case, both the lesion and parenchyma enhanced maximally on the delayed sequence. Magnetic resonance assessed lesion size accurately and also detected satellite malignancies in one case. However, lesion grade, associated in situ carcinoma and lymphovascular invasion did not impact on lesion enhancement. In this small series, a contrast-enhanced, fat-suppressed 3-D Gradient Echo Sequence detected breast carcinoma with high sensitivity. The technique holds promise but further evaluation is required.  相似文献   
34.
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
35.
36.
Badami  JP; Baker  RA; Scholz  FJ; McLaughlin  M 《Radiology》1986,158(1):175-177
A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings.  相似文献   
37.
Between December 1986 and October 1988, 83 patients with chronic peripheral artery occlusions were treated with a new technique. In 56 patients, the superficial femoral artery was completely occluded; in 21 patients, the popliteal artery; and in six patients, the iliac artery. The length of occlusion ranged from 5 to 35 cm (mean, 12.5 cm). The duration, estimated by history, was 5-48 months (mean, 16.5 months). In seven patients, durations of 6-36 months were documented angiographically. A flexible, blunt, motor-driven rotating catheter was introduced through an 8-F sheath, and rotational angioplasty was performed at low speed (up to 200 rpm). In 49 of 60 (82%) patients in whom this new technique was used as the primary intervention, the occlusions were successfully reopened. In 23 patients in whom conventional methods had failed more than 4 weeks earlier, the success rate for rotational angioplasty was 67% (12 of 18 patients); when the time interval was less than 4 weeks, only one of five patients was treated successfully. In none of the 83 patients did a perforation occur. This new technique can reopen chronic artery occlusions with a high degree of success and without the danger of vessel-wall perforation, even after failure of conventional techniques.  相似文献   
38.
39.
Scholz  FJ 《Radiology》1989,170(2):564-565
A device for manual compression and palpation during supine fluoroscopy has been designed. It enables effective use of the physiologic grasping and lever force potentials of the hand and wrist. The device permits optimal fluoroscopic palpation and compression techniques and prevents direct exposure to the lead-gloved hand.  相似文献   
40.
Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study. Cephalalgia 1994;1'4:270-1. Oslo. ISSN 0333-1024We prospectively studied over two years the incidence of headache as the initial and isolated clinical manifestation of adult patients suffering from intracranial tumors ( n = 183). Fifteen patients (8%) exhibited headache as their first and isolated clinical manifestation. Age, sex, neoplasm localization, or pathological diagnosis did not correlate with the presence of headache. Posterior fossa location and hydrocephalus, though not reaching statistical significance, were more frequent in patients who presented with headache as the first symptom. At the moment of diagnosis, 59 (31%) of the patients admitted to headache, though only I out of the 15 patients starting as headache still had this symptom as the only manifestation. From our experience in adults, isolated headache for longer than 10 weeks will only exceptionally be secondary to an intracranial neoplasm.  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