全文获取类型
收费全文 | 787篇 |
免费 | 22篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 6篇 |
妇产科学 | 3篇 |
基础医学 | 92篇 |
口腔科学 | 51篇 |
临床医学 | 48篇 |
内科学 | 95篇 |
皮肤病学 | 5篇 |
神经病学 | 165篇 |
特种医学 | 89篇 |
外科学 | 59篇 |
综合类 | 23篇 |
预防医学 | 21篇 |
眼科学 | 10篇 |
药学 | 98篇 |
中国医学 | 15篇 |
肿瘤学 | 31篇 |
出版年
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 15篇 |
2014年 | 27篇 |
2013年 | 34篇 |
2012年 | 35篇 |
2011年 | 41篇 |
2010年 | 28篇 |
2009年 | 49篇 |
2008年 | 64篇 |
2007年 | 42篇 |
2006年 | 43篇 |
2005年 | 29篇 |
2004年 | 35篇 |
2003年 | 32篇 |
2002年 | 26篇 |
2001年 | 24篇 |
2000年 | 21篇 |
1999年 | 26篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1996年 | 18篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 12篇 |
1992年 | 10篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 15篇 |
1988年 | 15篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 12篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 3篇 |
1978年 | 3篇 |
1977年 | 7篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有816条查询结果,搜索用时 0 毫秒
81.
目的:研究老年性痴呆(AD)和血管性痴呆(VD)患者睡眠障碍的特点及相关性。方法:对31例AD患者和30例VD患者采用阿森斯(Athens)失眠量表调查评分及临床资料比较分析。对研究对象进行筛选分组。从8个方面详细记录睡眠情况,按量表现规定进行评定。结果:AD患者和VD患者总体睡眠状况比较有显著性差异(t=2.251,P<0.05)。睡眠状况各因子比较,在总睡眠质量、白天情绪、白天思睡等3个方面无显著性差异(P>0.05)。在早醒、白天身体功能方面,两者有极显著差异(P<0.01)。在入睡时间、夜间苏醒、总睡眠时间等两者存在显著性差异(P<0.05)。结论:AD患者和VD患者都有睡眠障碍,AD患者在早醒、白天身体功能、夜间苏醒、总睡眠时间等方面都比VD患者差,而VD患者在入睡时间上比AD患者明显延迟。 相似文献
82.
Objective To investigate the kinetics of PML-RARα fusion gene in acute promyelocytic leukemia(APL)to monitor minimal residual disease(MRD). Methods In induction therapy,consolidation and maintenance therapy courses, PML-RARα fusion gene was performed by RT-PCR. Results The long-term follow-up of 18 cases achieved complete remission (CR),two cases experienced molecular relapse. One case relapsed at 4 months after CR1 and achieved CR2 after induction therapy. However, molecular and hematology relapsed again at 2 months after CR2 and re-achieved CR3. The other case relapsed at 74 months after CR1 and achieved CR2 after induction treatment, who had survived for 106 months until the end of follow-up. Conclusion RT-PCR assay for detection of PML-RARα should be performed regularly during CR period so as to find molecular relapse eady. Hematological relapse could potentially be averted through treatment modification according to molecular monitoring results of PML-RARα. 相似文献
83.
The trouble with family medicine 总被引:1,自引:1,他引:0
BACKGROUND: The trouble with family medicine is that the perceptual
framework it uses to view the phenomena of health and illness is at
variance with the frameworks traditionally used by medicine generally. This
creates difficulties in communication between those in family medicine and
those in other disciplines, and sometimes leads to misunderstanding of the
nature of the discipline of family medicine and its place in the health
care system. Those who practise family medicine need to be 'multilingual',
able to understand and speak the language and use the metaphors of family
medicine, yet equally able to use the language and metaphors of other
disciplines. OBJECTIVES: This paper, which begins with a clinical scenario,
reviews the contemporary biomedical paradigm, proposes an alternative, and
examines the conceptual frameworks which underpin the discipline of family
medicine.
相似文献
84.
W S Pierce G Rosenberg A J Snyder W E Pae Jr J H Donachy J A Waldhausen 《Annals of surgery》1990,212(3):339-344
Advances in microelectronics, high-strength magnets, and control system design now make replacement of the heart using an implantable, electrically powered pump feasible. The device described herein is a compact, dual pusher plate unit with valved polyurethane sac-type ventricles positioned at either end. The power unit consists of a small, brushless direct current motor and a motion translator. A microprocessor control system is used to regulate heart beat rate and provide left-right output balance. Bench studies lasting for as long as 1 year have been performed. Heart replacement with the electric heart has been performed in 18 calves since 1984. The longest survivor lived for more than 7 months. Among the causes of termination were component failure, thromboembolic complications, and bleeding. No major problem has been identified that precludes prolonged use of the electric heart. In the future the patient with end-stage heart disease will have an electric artificial heart as one therapeutic option. 相似文献
85.
Rapid mobilization of hematopoietic progenitor cells in rhesus monkeys by a single intravenous injection of interleukin-8 总被引:13,自引:6,他引:13
Laterveer L; Lindley IJ; Heemskerk DP; Camps JA; Pauwels EK; Willemze R; Fibbe WE 《Blood》1996,87(2):781-788
Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation. 相似文献
86.
Bone marrow transplantation (BMT) is often followed by significant morbidity and mortality due to protracted immunodeficiency. We have hypothesized that the bone marrow-ablative regimen may delay the recovery of normal immune function following transplantation by impairing the interaction of host endothelial cells with circulating graft-derived lymphocytes. This report compares the relative effects of busulfan (an alkylating drug) and gamma-irradiation on the tissue- specific localization potential of lymphocytes and the eventual recovery of immune function within syngeneic murine transplant recipients. Localization of normal lymphocytes into peripheral lymph nodes of irradiated BMT recipients was markedly less (less than 50%) than in busulfan-treated or normal mice over the first 2 months post- BMT. This finding correlated with irradiation-induced endothelial cell edema and microvascular occlusions within lymphocyte-receptive areas of the nodal microvasculature. The effect of both preparative regimens on the recovery of contact hypersensitivity (CHS) was also analyzed. This response recovered more quickly (between 1 and 2 months) in busulfan- pretreated animals. Further experiments demonstrated that the decrease in CHS responsiveness appeared, in part, related to a depression in the capacity of lymphocytes to localize into skin sites of antigen deposition within irradiated mice. The impairment of tissue-specific lymphocyte localization may represent a novel mechanism by which whole body irradiation can contribute to delayed immunologic reconstitution following bone marrow transplantation. 相似文献
87.
G Lesage SS Glaser S Gubba WE Robertson JL Phinizy J Lasater RE Rodgers G Alpini 《Gastroenterology》1996,111(6):1633-1644
BACKGROUND & AIMS: After partial hepatectomy, liver regeneration occurs with the return of hepatocyte mass to normal, Limited data exist regarding the renewal of the biliary tree after partial hepatectomy. This study tested the hypothesis that, after partial hepatectomy, the biliary tree regenerates by proliferation of the remaining cholangiocytes, leading to an increase in secretin-induced ductal bile secretion. METHODS: After 70% partial hepatectomy, cholangiocyte proliferation was assessed in situ by morphometric analysis and In vitro by measurement of 3H-thymidine incorporation. Ductal secretion was estimated by measurement of secretin receptor gene expression and adenosine 3',5'-cyclic monophosphate (cAMP) levels in vitro and by the effect of secretin on ductal bile secretion in vivo. RESULTS: DNA synthesis was undetectable in control cholangiocytes, increased and peaked at day 3 after partial hepatectomy, and returned to normal by day 28. Morphometric analysis showed regrowth of the biliary tree beginning at day 1 with restoration by day 10. The expression of secretin receptor gene and secretin-induced cAMP levels and secretin- induced bicarbonate-rich choleresis increased during the period of bile duct renewal. CONCLUSIONS: After partial hepatectomy, the increase in secretin-induced ductal bile secretion observed during bile duct renewal results from proliferation of remaining cholangiocytes. (Gastroenterology 1996 Dec;111(6):1633-44) 相似文献
88.
89.
90.
Drug-induced thrombocytopenia is associated with increased binding of IgG to platelets both in vivo and in vitro 总被引:3,自引:0,他引:3
Kelton JG; Meltzer D; Moore J; Giles AR; Wilson WE; Barr R; Hirsh J; Neame PB; Powers PJ; Walker I; Bianchi F; Carter CJ 《Blood》1981,58(3):524-529
Thrombocytopenia is a common serious adverse effect of drug treatment. A variety of in vitro diagnostic techniques to confirm the diagnosis are available, but the majority lack sufficient sensitivity to detect all cases of drug-induced thrombocytopenia. We studied 19 patients with suspected drug-induced thrombocytopenia and demonstrated that platelet- associated IgG (PAIgG) was elevated in all at the time of thrombocytopenia, and PAIgG returned to normal levels as the thrombocytopenia resolved. In the majority of patients, the platelet count rapidly returned to normal after the drug was discontinued; however, in six patients, the thrombocytopenia persisted well beyond the period of time that the offending drug would be expected to be cleared from the blood. In 13 patients, serum obtained after recovery was used to identify the drug responsible for the thrombocytopenia in an in vitro assay. In all cases, the addition of the drug historically associated with the thrombocytopenic episode was associated with an increased binding of IgG to control platelets. For uncertain reasons, the concentration of drug required to increase the in vitro binding of IgG to test platelets was often more than the concentration usually achieved in vivo. Wider application of these techniques may provide better understanding of the clinical characteristics and mechanisms responsible for drug-induce thrombocytopenia. 相似文献