全文获取类型
收费全文 | 1635篇 |
免费 | 144篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 43篇 |
妇产科学 | 103篇 |
基础医学 | 145篇 |
口腔科学 | 34篇 |
临床医学 | 273篇 |
内科学 | 397篇 |
皮肤病学 | 5篇 |
神经病学 | 92篇 |
特种医学 | 176篇 |
外科学 | 112篇 |
综合类 | 49篇 |
预防医学 | 116篇 |
眼科学 | 2篇 |
药学 | 85篇 |
中国医学 | 2篇 |
肿瘤学 | 145篇 |
出版年
2023年 | 9篇 |
2022年 | 15篇 |
2021年 | 18篇 |
2020年 | 17篇 |
2019年 | 17篇 |
2018年 | 23篇 |
2017年 | 23篇 |
2016年 | 25篇 |
2015年 | 27篇 |
2014年 | 36篇 |
2013年 | 58篇 |
2012年 | 44篇 |
2011年 | 57篇 |
2010年 | 40篇 |
2009年 | 67篇 |
2008年 | 74篇 |
2007年 | 60篇 |
2006年 | 62篇 |
2005年 | 72篇 |
2004年 | 46篇 |
2003年 | 37篇 |
2002年 | 56篇 |
2001年 | 34篇 |
2000年 | 53篇 |
1999年 | 44篇 |
1998年 | 51篇 |
1997年 | 42篇 |
1996年 | 52篇 |
1995年 | 48篇 |
1994年 | 37篇 |
1993年 | 36篇 |
1992年 | 25篇 |
1991年 | 29篇 |
1990年 | 29篇 |
1989年 | 45篇 |
1988年 | 44篇 |
1987年 | 34篇 |
1986年 | 25篇 |
1985年 | 36篇 |
1984年 | 19篇 |
1983年 | 20篇 |
1982年 | 29篇 |
1981年 | 27篇 |
1980年 | 26篇 |
1979年 | 28篇 |
1978年 | 18篇 |
1977年 | 22篇 |
1976年 | 11篇 |
1975年 | 9篇 |
1969年 | 7篇 |
排序方式: 共有1800条查询结果,搜索用时 15 毫秒
1.
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
4.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
5.
Brian F O'Reilly Ameet Kishore John A Crowther Colin Smith 《Otology & neurotology》2004,25(5):791-796
OBJECTIVE: To examine the relationship between growth rate of vestibular schwannomas and the expression of various growth factor receptors. STUDY DESIGN: Retrospective case review of clinical growth rate in conjunction with a histopathologic and immunohistochemical reexamination of archival specimens. SETTING: A tertiary referral neurotologic center. PATIENTS: Three groups: a historical group to act as controls, consisting of 30 patients with sporadic vestibular schwannomas removed before the unit adopted an initial interval scan policy; a group of 14 patients with sporadic vestibular schwannomas who had undergone an initial interval scan policy, showed radiologic evidence of growth, and therefore had their schwannoma removed; and a group of 16 schwannomas removed from 11 neurofibromatosis Type 2 patients. MAIN OUTCOME MEASURES: A comparison between the three clinical groups using immunohistochemical studies to determine the level of expression of the proliferation factor Ki-67, c-erbB-2, and c-erbB-3 receptors and fibroblastic growth factor receptors 1 and 4. RESULTS: The level of expression of the proliferation factor Ki-67 was very low and similar in all three groups. C-erbB-2 and c-erbB-3 receptors were not expressed in any of the groups. fibroblastic growth factor receptor 4 expression was not significantly different, but there was a variation in the expression of fibroblastic growth factor receptor 1 between the three groups that correlated well with the differing incidence of growth in the groups. The increase in expression of fibroblastic growth factor receptor 1 in the neurofibromatosis Type 2 group was not statistically significant, but the increase in expression of fibroblastic growth factor receptor 1 in the growing sporadic group was statistically significant when compared with the historical controls. The level of fibroblastic growth factor receptor 1 expression correlates significantly with the rate of growth as measured on interval magnetic resonance imaging. CONCLUSIONS: Overexpression of fibroblastic growth factor receptor 1 has a positive correlation with the incidence and the rate of growth of sporadic vestibular schwannomas. 相似文献
6.
7.
8.
J. Wagstaff I. Todd D. Deakin P. Wilkinson J. H. Scarffe M. Harris M. Jones D. Crowther 《Cancer chemotherapy and pharmacology》1987,20(1):53-58
Summary This paper reports the 8-year results of comparing the use of two types of adjuvant chemotherapy following involved field radiotherapy for clinical stages I and II high-grade non-Hodgkin's lymphoma. Twenty-four patients received 6 weeks of VAP plus 2 years of oral maintenance chemotherapy, and 30 had six cycles of CMOPP. Four patients were not in complete remission at completion of i. v. chemotherapy (CR rate 91%). Ten patients (18.5%) have relapsed (VAP/M=5; CMOPP=5), with only two of these remaining alive, both of them being disease free. There have been three deaths from intercurrent causes, one from malignant melanoma and the other two from myocardial infarction. The relapse-free survivals at 2, 5 and 8 years were 80%, 76% & 76% respectively. The overall survivals at the same time points were 86%, 72% & 68%. There were no significant differences in either relapse-free or overall survival for either of the two treatment groups. The shorter period of weekly intravenous chemotherapy (VAP/M) was better tolerated than 36 weeks of CMOPP, and the former appears to produce equivalent results. 相似文献
9.
W P Steward D Crowther L J McWilliam J M Jones D P Deakin I D Todd G Blackledge J Wagstaff J H Scarffe M Harris 《Cancer》1988,61(3):441-447
One hundred sixty-two patients with Stages III and IV non-Hodgkin's lymphoma of low-grade histologic type were treated with combination chemotherapy using cyclophosphamide, vincristine, and prednisolone (CVP) followed by radiotherapy to sites of previous bulk disease. The patients were randomized to receive either follow-up alone or "maintenance" chemotherapy with 2 years of intermittent chlorambucil. A complete remission was obtained in 56% of patients and the median survival was 64 months (median follow-up, 74 months). Multivariate analysis revealed stage (P less than 0.0001) and Karnofsky performance status (P = 0.021) to predict complete response (CR) and the achievement of a CR (P less than 0.0001), female sex (P = 0.008), the absence of bulk disease (P = 0.038) and low serum alkaline phosphatase (P = 0.002) to predict prolonged survival. The median relapse-free survival (RFS) of the complete responders was 41 months. A prolonged RFS was predicted by low stage (P = 0.014), low serum lactic dehydrogenase (LDH) (P = 0.045) levels, and by the administration of maintenance chlorambucil (P = 0.045). A prolonged survival of the complete responders was predicted by a low number of nodal sites of involvement with lymphoma at presentation (P = 0.022) and lack of liver involvement (P = 0.011). The administration of oral maintenance therapy with chlorambucil for a full 2 years was only possible in 38% of patients, mainly because of progression of disease and the induction of thrombocytopaenia, but despite this it prolonged the median RFS by 38 months and its use could be considered when future studies are being designed. 相似文献
10.
Molecular approach to the epidemiology of swine vesicular disease: correlation of variation in the virus structural polypeptides with serological properties.
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T J Harris B O Underwood N J Knowles J R Crowther F Brown 《Infection and immunity》1979,24(3):593-599
Variation has been observed in the structural polypeptides of swine vesicular disease viruses isolated from the United Kingdom and Hong Kong. Despite the limited number of isolates examined, several distinct polypeptide patterns were obtained when the virus structural proteins were examined by polyacrylamide gel electrophoresis. Isolates from outbreaks in the United Kingdom which were known to be connected gave the same polypeptide pattern, whereas viruses with different polypeptide patterns could not be traced to a common source. The different polypeptide patterns were obtained consistently and were not altered by passage of the virus in tissue culture. In general, isolates with identical polypeptide patterns could not be distinguished by neutralization or antibody blocking tests or by competition radioimmunoassays. However, isolates with different polypeptide patterns could be differentiated by antibody blocking tests or radioimmunoassay. The correlation between the serological tests and the polyacrylamide gel electrophoresis analyses illustrates the value of analyzing structural polypeptides in the epidemiological study of swine vesicular disease. 相似文献