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   202篇
  免费   5篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   14篇
妇产科学   6篇
基础医学   37篇
口腔科学   8篇
临床医学   15篇
内科学   47篇
皮肤病学   2篇
神经病学   11篇
特种医学   10篇
外国民族医学   1篇
外科学   12篇
综合类   7篇
预防医学   17篇
眼科学   2篇
药学   11篇
中国医学   1篇
肿瘤学   7篇
  2023年   1篇
  2021年   3篇
  2017年   1篇
  2016年   1篇
  2015年   5篇
  2014年   5篇
  2013年   6篇
  2012年   10篇
  2011年   2篇
  2010年   6篇
  2009年   12篇
  2008年   8篇
  2007年   7篇
  2006年   7篇
  2005年   5篇
  2004年   7篇
  2003年   8篇
  2002年   2篇
  2001年   9篇
  2000年   7篇
  1999年   8篇
  1998年   5篇
  1997年   9篇
  1996年   11篇
  1994年   4篇
  1993年   2篇
  1992年   3篇
  1991年   3篇
  1990年   6篇
  1989年   5篇
  1988年   5篇
  1987年   9篇
  1986年   3篇
  1985年   5篇
  1984年   2篇
  1982年   7篇
  1981年   1篇
  1980年   1篇
  1978年   2篇
  1976年   2篇
  1973年   1篇
  1972年   1篇
  1970年   1篇
  1969年   1篇
  1965年   1篇
排序方式: 共有210条查询结果,搜索用时 265 毫秒
1.
Interleukin 6 (IL6) is one of the major inflammation-associated cytokines. Elevated serum or tissue levels of IL6 have been reported to occur in several human diseases, including infections of the central nervous system (CNS), but not in non-infectious CNS inflammation, e.g. multiple sclerosis. While studying experimental autoimmune encephalomyelitis (EAE) as an animal model for autoimmune inflammation of the CNS, we found increased IL6 levels in the CNS of mice suffering from a lethal form of the disease. IL6 levels in the spleens and sera were not significantly increased. These findings are indicative of local production of IL6 in the CNS during EAE, and represent the first demonstration of IL6 production in non-infectious CNS inflammatory disease.  相似文献   
2.
An effort is being made in Cambodia to involve grass-roots personnel in the integration of the care of the mentally ill into a broad framework of health services. This undertaking is examined with particular reference to the work of the Transcultural Psychosocial Organization.  相似文献   
3.
4.
Sitnicka  E; Lin  N; Priestley  GV; Fox  N; Broudy  VC; Wolf  NS; Kaushansky  K 《Blood》1996,87(12):4998-5005
In this study, we explored whether thrombopoietin (Tpo) has a direct in vitro effect on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC). We previously reported a cell separation method that uses the fluorescence-activated cell sorter selection of low Hoescht 33342/low Rhodamine 123 (low Ho/low Rh) fluorescence cell fractions that are highly enriched for LTR-HSC and can reconstitute lethally irradiated recipients with fewer than 20 cells. Low Ho/low Rh cells clone with high proliferative potential in vitro in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6 (90% to 100% HPP-CFC). Tpo alone did not induce proliferation of these low Ho/low Rh cells. However, in combination with SCF or IL-3, Tpo had several synergistic effects on cell proliferation. When Tpo was added to single growth factors (either SCF or IL-3 or the combination of both), the time required for the first cell division of low Ho/low Rh cells was significantly shortened and their cloning efficiency increased substantially. Moreover, the subsequent clonal expansion at the early time points of culture was significantly augmented by Tpo. Low Ho/low Rh cells, when assayed in agar directly after sorting, did not form megakaryocyte colonies in any growth condition tested. Several days of culture in the presence of multiple cytokines were required to obtain colony-forming units-megakaryocyte (CFU-Mk). In contrast, more differentiated, low Ho/high Rh cells, previously shown to contain short- term repopulating hematopoietic stem cells (STR-HSC), were able to form megakaryocyte colonies in agar when cultured in Tpo alone directly after sorting. These data establish that Tpo acts directly on primitive hematopoietic stem cells selected using the Ho/Rh method, but this effect is dependent on the presence of pluripotent cytokines. These cells subsequently differentiate into CFU-Mk, which are capable of responding to Tpo alone. Together with the results of previous reports of its effects on erythroid progenitors, these results suggest that the effects of Tpo on hematopoiesis are greater than initially anticipated.  相似文献   
5.
For the first time, the Canadian Hypertension Education Program has studied the evidence supporting blood pressure control in people requiring renal replacement therapy for end-stage kidney disease, including those on dialysis and with renal transplants. According to the Canadian Organ Replacement Registry’s 2008 annual report, there were an estimated 33,832 people with end-stage renal disease in Canada at the end of 2006, an increase of 69.7% since 1997. Of these, 20,465 were on dialysis and 13,367 were living with a functioning kidney transplant. Thus, it is becoming more likely that primary care practitioners will be helping to care for these complex patients. With the lack of large controlled clinical trials, the consensus recommendation based on interpretation of the existing literature is that blood pressure should be lowered to below 140/90 mmHg in hypertensive patients on renal replacement therapy and to below 130/80 mmHg for renal transplant patients with diabetes or chronic kidney disease.  相似文献   
6.
Aim: The aim of the student is to assess whether adolescents with type 1 diabetes mellitus (T1DM) in Italy differ from their healthy peers in regard to risky behaviour. Methods: Data were collected from 215 patients, aged 14 ± 2 years with a mean disease duration of 7 ± 5 years. The control group was comprised of 464 healthy adolescents recruited among high school students. Each patient completed an anonymous confidential questionnaire to determine the prevalence of sexual behaviour, alcohol and tobacco consumption, illicit drug use, and, among patients with diabetes and frequency of mismanagement related to diabetes care. Results: Compared with controls, subjects with diabetes showed a similar rate of sexual intercourse among males and lower rates among females (34.8% vs 35.5%, p NS and 29.4% vs 41.4%, p < 0.05, respectively). Males in the diabetes group reported a higher rate of tobacco use, whereas females showed similar or higher rates of use for every illicit drug studied. Among patients with diabetes, those who are engaged in risky behaviour showed a higher rate of treatment mismanagement (76% vs 34%, p < 0.01). Conclusion: Adolescents with T1DM are as likely as their healthy peers to engage in risky behaviour, indicating the potential benefit of anticipatory guidance concerning glycaemic control and increased risk of acute and chronic complications.  相似文献   
7.
Twenty-one oligosaccharides of human milk were quantified by high-performance anion-exchange chromatography. Milk samples were collected from 18 mothers during the first 3 mo of lactation. The data show that the highest amount of all oligosaccharides is present at day 4 postpartum (20 g l−1) and then decreases by about 20% at day 30 of lactation. The protective role played by these substances against different infectious agents, in different organs and systems of the breastfed baby, is emphasized.  相似文献   
8.
MRI/linac integration.   总被引:1,自引:1,他引:1  
PURPOSE/OBJECTIVES: In radiotherapy the healthy tissue involvement still poses serious dose limitations. This results in sub-optimal tumour dose and complications. Daily image guided radiotherapy (IGRT) is the key development in radiation oncology to solve this problem. MRI yields superb soft-tissue visualization and provides several imaging modalities for identification of movements, function and physiology. Integrating MRI functionality with an accelerator can make these capacities available for high precision, real time IGRT. DESIGN AND RESULTS: The system being built at the University Medical Center Utrecht is a 1.5T MRI scanner, with diagnostic imaging functionality and quality, integrated with a 6MV radiotherapy accelerator. The realization of a prototype of this hybrid system is a joint effort between the Radiotherapy Department of the University of Utrecht, the Netherlands, Elekta, Crawley, U.K., and Philips Research, Hamburg, Germany. Basically, the design is a 1.5 T Philips Achieva MRI scanner with a Magnex closed bore magnet surrounded by a single energy (6 MV) Elekta accelerator. Monte Carlo simulations are used to investigate the radiation beam properties of the hybrid system, dosimetry equipment and for the construction of patient specific dose deposition kernels in the presence of a magnetic field. The latter are used to evaluate the IMRT capability of the integrated MRI linac. CONCLUSIONS: A prototype hybrid MRI/linac for on-line MRI guidance of radiotherapy (MRIgRT) is under construction. The aim of the system is to deliver the radiation dose with mm precision based on diagnostic quality MR images.  相似文献   
9.
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.  相似文献   
10.
OBJECTIVE: To study the compliance and changes in plasma lipids, plant sterols, fat-soluble vitamins and carotenoids in children and parents with familial hypercholesterolemia (FH) consuming a plant sterol ester-enriched (PSE) spread. DESIGN: A 26-week open-label follow-up of children who had previously been studied in a controlled cross-over design. The parents were also included in the open-label arm of the study. SETTING: Outpatient clinic for treatment of hyperlipidemia. SUBJECTS: A total of 37 children (7-13 y) and 20 parents (32-51 y) diagnosed with 'definite' or 'possible' heterozygous FH. In all, 19 of the parents, but no children, used statins. All were patients at the Lipid Clinic, National Hospital in Oslo. INTERVENTIONS: Subjects were recommended to eat 20 g/day of PSE spread as part of their lipid-lowering diet. RESULTS: The mean intake of PSE spread was 13.7 and 16.5 g/days in the children and parents, respectively, corresponding to 1.2 and 1.5 g of plant sterols. Plasma total cholesterol decreased by 9.1% in both children (P<0.001) and parents (P=0.002). The corresponding decreases in LDL cholesterol were 11.4% (P<0.001) and 11.0% (P=0.012). Increases in serum lathosterol, campesterol and sitosterol, adjusted for total cholesterol, were observed in the children (31, 96, 48%, respectively, P<0.001) at the end of the controlled cross-over period. In the parents, serum campesterol and sitosterol, adjusted for total cholesterol, increased by 92 and 39%, respectively (P< 0.001). Lipid-adjusted serum alpha- and beta-carotene decreased by 17.4% (P=0.008) and 10.9% (P=0.018), respectively, in the children at the end of the controlled PSE period, but increased again during the follow-up. In the parents, serum alpha- and beta-carotene concentrations were unchanged, while serum lutein and lycopene decreased by 7.3% (P=0.037) and 14.6% (P=0.044), respectively. CONCLUSIONS: Sustained efficacy of cholesterol reduction and long-term compliance of PSE intake were demonstrated in this study.  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