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   255篇
  免费   25篇
  国内免费   38篇
儿科学   9篇
妇产科学   3篇
基础医学   26篇
临床医学   36篇
内科学   50篇
皮肤病学   1篇
神经病学   4篇
特种医学   100篇
外科学   16篇
综合类   31篇
预防医学   21篇
药学   17篇
肿瘤学   4篇
  2020年   1篇
  2017年   2篇
  2016年   1篇
  2015年   4篇
  2014年   5篇
  2013年   8篇
  2012年   5篇
  2011年   4篇
  2010年   1篇
  2009年   6篇
  2008年   3篇
  2007年   23篇
  2006年   9篇
  2005年   14篇
  2004年   5篇
  2003年   3篇
  2002年   5篇
  2001年   5篇
  2000年   5篇
  1999年   4篇
  1998年   17篇
  1997年   10篇
  1996年   12篇
  1995年   17篇
  1994年   10篇
  1993年   12篇
  1992年   3篇
  1991年   4篇
  1990年   10篇
  1989年   20篇
  1988年   13篇
  1987年   14篇
  1986年   8篇
  1985年   8篇
  1984年   3篇
  1983年   5篇
  1982年   5篇
  1981年   10篇
  1980年   3篇
  1979年   1篇
  1978年   2篇
  1977年   4篇
  1976年   3篇
  1975年   4篇
  1974年   2篇
  1973年   1篇
  1971年   1篇
  1967年   1篇
  1956年   1篇
  1936年   1篇
排序方式: 共有318条查询结果,搜索用时 15 毫秒
311.
Hankins  WD; Schooley  J; Eastment  C 《Blood》1986,68(1):263-268
Production of lymphoid and myeloid growth regulatory factors by hematopoietic cells is well documented. On the other hand, the major site of production of erythropoietin (Epo), which regulates physiologic red blood cell development, is thought to be the kidney. Here we report the isolation of multiple erythroleukemia cell lines that produce erythropoietic factors and present extensive biological, immunologic, and biochemical evidence to document that the active agent is Epo. The erythropoietic activity was neutralized by Epo antiserum and exhibited physical properties indistinguishable from those of human and sheep Epo. Positive lines produced between 0.1 and 1.5 U/mL of Epo, which stimulated erythropoiesis in vivo and in vitro in nine biological assays. Twenty sublines derived from single cells were inducible for hemoglobin and spectrin synthesis. All the sublines produced Epo. Production of the hormone continued when the cells were seeded in the absence of serum. Our finding that multiple independent isolates produce Epo raises the possibility that Epo production by erythroid precursors may play a role in normal erythropoiesis or, alternatively, that Epo gene activation may be a relatively common occurrence that contributes to, or is associated with, certain forms of virus-induced leukemias.  相似文献   
312.
IntroductionIn April 2011 the NI public health agency estimated that alcohol misuse generates overall annual healthcare costs of £122.2m. There is currently a paucity of data regarding the burden of alcohol-related fractures on the provinces Trauma and Orthopaedic service.ResultsAlcohol related fractures accounted for 6.1% of all acute fractures admissions in the 12 month period. 73% were male, with a bimodal age distribution. The majority of patients were classed as social drinkers; however a significant proportion (23.1%) were alcohol dependent. 62.5% of patients were smokers at the time of admission. 95% of patients suffered a single injury which was commonly secondary to a simple mechanical fall (53.8%). The majority of patients sustained lower limb injuries, with 30.8% of these being ankle fractures.ConclusionIn conclusion, our study has identified that alcohol-related trauma creates a significant financial burden on the NHS. It is likely that the incidence of alcohol related fracture is higher than documented in this study. We advocate the assessment of patients using the AUDIT-C score to assess for at risk drinking behaviour in those presenting with an alcohol related fracture.  相似文献   
313.
IL6expressionintransferredNIH3T3celsbyretrovirusvectorXIAOBing1,JIANGBo2,ZHOUDianYuan2andZHANGWanDai21DepartmentofDigestion...  相似文献   
314.
Predictive ability of a positive Tinel sign over the tibial nerve in the tarsal was evaluated as a prognostic sign in determining sensory outcomes after distal tibial neurolysis in diabetics with chronic nerve compression at this location. Outcomes were evaluated with a visual analog score (VAS) for pain and measurements of the cutaneous pressure threshold/two-point discrimination. A multicenter prospective study enrolled 628 patients who had a positive Tinel sign. Of these patients, 465 (74%) had VAS >5. Each patient had a release of the tarsal tunnel and a neurolysis of the medial and lateral plantar and calcaneal tunnels. Subsequent, contralateral, identical surgery was done in 211 of the patients (152 of which had a VAS >5). Mean VAS score decreased from 8.5 to 2.0 (p <0.001) at 6 months, and remained at this level for 3.5 years. Sensibility improved from a loss of protective sensation to recovery of some two-point discrimination during this same time period. It is concluded that a positive Tinel sign over the tibial nerve at the tarsal tunnel in a diabetic patient with chronic nerve compression at this location predicts significant relief of pain and improvement in plantar sensibility.  相似文献   
315.
Plantar fasciitis is a common cause of heel pain, and although treatments are usually conservative, they can take up to 2 years to achieve resolution. A double-blind, multicenter, randomized, placebo-controlled study was used to evaluate a small, wearable, extended-use pulsed radiofrequency electromagnetic field (PRFE) device as a treatment of plantar fasciitis. A total of 70 subjects diagnosed with plantar fasciitis were enrolled in the present study. The subjects were randomly assigned a placebo or active PRFE device. The subjects were instructed to wear the PRFE device overnight, record their morning and evening pain using a 0- to 10-point visual analog scale (VAS), and log any medication use. The primary outcome measure for the present study was morning pain, a hallmark of plantar fasciitis. The study group using the active PRFE device showed progressive decline in morning pain. The day 7 AM-VAS score was 40% lower than the day 1 AM-VAS score. The control group, in comparison, showed a 7% decline. A significantly different decline was demonstrated between the 2 groups (p = .03). The PM-VAS scores declined by 30% in the study group and 19% in the control group, although the difference was not significant. Medication use in the study group also showed a trend downward, but the use in the control group remained consistent with the day 1 levels. PRFE therapy worn on a nightly basis appears to offer a simple, drug-free, noninvasive therapy to reduce the pain associated with plantar fasciitis.  相似文献   
316.
SUMMARY A study conducted of the collection of samples from patients dying in hospital and the results of their analysis found that samples are often collected unnecessarily from patients dying in hospital, and are collected more often from women than from men.  相似文献   
317.
Carvalho DR, Navarro MMM, Martins BJAF, Coelho KEFA, Mello WD, Takata RI, Speck‐Martins CE. Mutational screening of ACVR1 gene in Brazilian fibrodysplasia ossificans progressiva patients. Fibrodysplasia ossificans progressiva (FOP) is a severe genetic disorder reported worldwide. A specific heterozygous mutation (c.617G> A; p.R206H) in the activin A type I receptor gene (ACVR1) is regarded as the genetic cause of FOP in all classically affected individuals worldwide. However, a few patients with FOP variants harbor distinct mutations in ACVR1. We screened a group of FOP Brazilian population for mutations in ACVR1. Of 16 patients with a classic FOP phenotype (10 males and 6 females, age range of 3–42 years), all had the classic mutation (p.R206H). One 21‐year‐old woman with a variant FOP phenotype had the previously reported c.983G> A mutation (p.G328E). Our study contributes to the understanding of the predominant FOP phenotype and genotype and suggests that variant FOP phenotypes are associated with specific mutations in ACVR1 gene.  相似文献   
318.
Hairy cell leukemia (HCL) is frequently associated with severe pancytopenia. The authors detected high levels of tumor necrosis factor (TNF)-alpha in the bone marrow serum of patients with HCL and found anti-TNF-alpha neutralizing monoclonal antibodies (MoAbs) to be able to enhance hematopoiesis of HCL patients in in vitro colony assays. As potent producers of TNF-alpha, hairy cells could be identified, thus implicating the malignant population in the pathogenesis of hematopoietic failure due to inappropriate secretion of this cytokine.  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