全文获取类型
收费全文 | 3386篇 |
免费 | 439篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 57篇 |
儿科学 | 75篇 |
妇产科学 | 297篇 |
基础医学 | 342篇 |
口腔科学 | 40篇 |
临床医学 | 977篇 |
内科学 | 489篇 |
皮肤病学 | 262篇 |
神经病学 | 230篇 |
特种医学 | 291篇 |
外国民族医学 | 1篇 |
外科学 | 182篇 |
综合类 | 60篇 |
预防医学 | 168篇 |
眼科学 | 45篇 |
药学 | 96篇 |
中国医学 | 2篇 |
肿瘤学 | 219篇 |
出版年
2023年 | 47篇 |
2022年 | 13篇 |
2021年 | 41篇 |
2020年 | 52篇 |
2019年 | 51篇 |
2018年 | 106篇 |
2017年 | 123篇 |
2016年 | 101篇 |
2015年 | 119篇 |
2014年 | 134篇 |
2013年 | 157篇 |
2012年 | 128篇 |
2011年 | 137篇 |
2010年 | 161篇 |
2009年 | 155篇 |
2008年 | 129篇 |
2007年 | 111篇 |
2006年 | 100篇 |
2005年 | 107篇 |
2004年 | 86篇 |
2003年 | 100篇 |
2002年 | 97篇 |
2001年 | 93篇 |
2000年 | 79篇 |
1999年 | 97篇 |
1998年 | 113篇 |
1997年 | 128篇 |
1996年 | 119篇 |
1995年 | 107篇 |
1994年 | 76篇 |
1993年 | 65篇 |
1992年 | 55篇 |
1991年 | 59篇 |
1990年 | 50篇 |
1989年 | 65篇 |
1988年 | 66篇 |
1987年 | 43篇 |
1986年 | 54篇 |
1985年 | 39篇 |
1984年 | 24篇 |
1983年 | 25篇 |
1982年 | 31篇 |
1981年 | 18篇 |
1980年 | 28篇 |
1979年 | 18篇 |
1978年 | 27篇 |
1977年 | 21篇 |
1976年 | 18篇 |
1975年 | 19篇 |
1974年 | 8篇 |
排序方式: 共有3833条查询结果,搜索用时 0 毫秒
81.
First Epidemiologic Study in Argentina of the Prevalence of BK Viruria in Kidney Transplant Patients
R. Schiavelli R. Bonaventura M.C. Rial H. Petrone G. Soler Pujol L.J. Gaite M. Acosta A. Gutierrez F. Acosta G. Valdez P. Raffaele G. Chanta M. Perez L. Potes E. Suso G. Cremades J. Ibañez N. Imperiali M.C. Freire 《Transplantation proceedings》2014,46(9):3010-3014
BackgroundThe worldwide seroprevalence of human BK polyomavirus (BKV) in adults is 80%. About 10%–60% of renal transplant recipients experience BKV infection, nephropathy of the graft may occur in 5% of the cases, and up to 45% lose the graft. The aim of this work was to describe the prevalence of BK viruria during the 1st year after transplantation.MethodsAn epidemiologic multicenter cross-sectional study was carried out in consecutive patients at each site with kidney transplantation from August 2011 to July 2012. Clinically significant viruria was defined as >107 copies/mL. Viral DNA was extracted with the use of silica columns. Quantification was performed with the use of real-time polymerase chain reaction with primers that amplify a fragment of the large T-antigen gene and with a specific Taqman-MGB probe for BKV. For each assay, a standard curve with a quantified plasmid was included.ResultsOf 402 renal transplant recipients at 18 renal transplant sites, we analyzed 382; median age was 46.33 years, and 46.40% were female. The median of the temporal distribution for urine samples was 153 days. BK virus was detected in 50/382 samples (13%), 18 with values >107 copies/mL (4.7%). The median of the distribution of positive values was 123 days and the highest frequency of positive values was in months 3–7. The conditions of recipient older than 34 years and donor older than 41 years were the only ones that showed statistically significant association with BK viruria. No association with any specific immunosuppressive drug was observed.ConclusionsThis is the first multicenter study conducted in Argentina to determine the prevalence of BK viruria in renal transplant recipients. Because of the growing number of the population susceptible to this infection, it is important to register and describe data about its epidemiology and associated risk factors. 相似文献
82.
de Koning JP; Dong F; Smith L; Schelen AM; Barge RM; van der Plas DC; Hoefsloot LH; Lowenberg B; Touw IP 《Blood》1996,87(4):1335-1342
83.
Using flow cytometry and osmotic lysis measurements, we document here the means and coefficients of variation of the following red cell (RBC) properties: hemoglobin (Hb) content, volume, Hb concentration, and relative lytic tonicity distributions in populations of normal human RBCs, before and after density fractionation. The distributions showed a pattern characterized by much larger coefficients of variation of the Hb content and volume distributions than of the Hb concentration and relative lytic tonicity distributions. From analysis of the factors that determine those RBC properties, the patterns were interpreted as reflecting previously unrecognized statistical proportionalities between cell osmolyte content, Hb content, and membrane area. The possible origin of these statistical links was analyzed by considering alternative models with and without the participation of regulatory processes during cell maturation. A model was shown to be feasible in which mature RBC variability with proportional volume, area, and Hb content arises solely from cell size variability at the last erythroid cell division. 相似文献
84.
O'Malley CJ; Rasko JE; Basser RL; McGrath KM; Cebon J; Grigg AP; Hopkins W; Cohen B; O'Byrne J; Green MD; Fox RM; Berndt MC; Begley CG 《Blood》1996,88(9):3288-3298
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status. 相似文献
85.
Prothrombotic state and signs of endothelial lesion in plasma of patients with inflammatory bowel disease 总被引:19,自引:0,他引:19
Dr. Joan Carles Souto MD Elisabet Martínez BSc Martí Roca PhD José Mateo MD Joan Pujol MD Dolors González MD Jordi Fontcuberta PhD 《Digestive diseases and sciences》1995,40(9):1883-1889
Recent investigations suggest that microthrombi formation in bowel capillaries could be a determinant factor in inflammatory bowel disease (IBD) pathogenesis. To evaluate the implication of the hemostatic system during these thrombotic events, we analyzed plasmatic values of prothrombotic state markers, physiologic inhibitors of coagulation, and endothelial lesion markers in 112 IBD patients. We found an increase in thrombin-antithrombin complexes and a decrease in antithrombin III, probably due to consumption, demonstrating an increase in thrombin generation. High levels ofd-dimer reflect increased fibrin formation, but there is no correlation between thrombin generation markers andd-dimer, possibly suggesting the presence of inadequate fibrinolysis. Levels of tissue factor pathway inhibitor were higher in patients than in controls. Nine patients with Crohn's disease (35% of our sample) had levels of this marker under 70% (range 37–69%). Von Willebrand factor values were increased and those of thrombomodulin only in active patients. Most of the changes were detected in patients with inflammatory activity, and there were no differences between ulcerative colitis and Crohn's disease. In conclusion, these results support the hypothesis that there is an endothelial lesion with sustained coagulation activation in IBD patients. 相似文献
86.
Kath Padgett BSc MA PGDip Cert Ed RMN Christine Rhodes BSc MSc RGN RM RN Child RHV Maureen Lumb Penny Morris BA Sue Sherwin BA MA PGCHE RMN Jools Symons BA MA Joannie Tate Ken Townend 《Health expectations》2014,17(3):418-428
Background Involving service users and carers in decisions about their health care is a key feature of health‐care practice. Professional health and social care students need to develop skills and attributes to best enable this to happen. Aims The aims were to explore service user and carer perceptions of behaviours, attributes and context required to enable shared decision making; to compare these perceptions to those of students and academic staff with a view to utilizing the findings to inform the development of student assessment tools. Methods A mixed methods approach was used including action learning groups (ALG) and an iterative process alongside a modified Delphi survey. Participants The ALGs were from an existing service user and carer network. The survey was sent to sixty students, sixty academics and 30 service users from 16 different professional disciplines, spanning four Universities in England. Results The collaborative enquiry process and survey identified general agreement that being open and honest, listening, showing respect, giving time and being up to date were important. The qualitative findings identified that individual interpretation was a key factor. An unexpected result was an insight into possible insecurities of students. Conclusions The findings indicate that distilling rich qualitative information into a format for student assessment tools could be problematic as the individual context could be lost, it is therefore proposed that the information could be better used as a learning rather than assessment tool. Several of those involved identified how they valued the process and found it beneficial. 相似文献
87.
Marta Malagn Sara Rami‐Pujol Marta Serrano Mariona Serra‐Pags Joan Amoedo Lia Oliver Anna Bahí Teresa MasdeXaxars Leyanira Torrealba Pau Gilabert Josep Oriol Miquel‐Cusachs Laura García‐Nimo Joan Sal Jordi Guardiola Virginia Piol Joaquin Cubiella Antoni Castells Xavier Aldeguer Jesús Garcia‐Gil 《Alimentary pharmacology & therapeutics》2019,49(11):1410-1420
88.
Azuaga A. B. Frade-Sosa B. Laiz A. Estrada P. Prior-Español A. Horcada L. Polino L. Moreno M. Moragues C. Urruticoechea-Arana A. Sellas A. Tandaipan J. L. Torrente-Segarra V. Garcia-Miguel J. Ros I. Ordoñez S. Moya P. Reina D. Mateo-Soria L. Fito C. Beltrán E. Pujol M. Cuervo A. M. Cañete J. D. Ramírez Julio 《Clinical rheumatology》2020,39(10):2963-2971
Clinical Rheumatology - To assess the effectiveness and survival of ustekinumab (UST) among patients with psoriatic arthritis (PsA) treated under routine clinical care. Multicenter study.... 相似文献
89.
Cristina Thompson MBA BA RN RM Elizabeth Halcomb PhD Grad Cert ICNurs Grad Cert HE BN RN FACN Malcolm Masso PhD MPH MNA BSc RN 《Scandinavian journal of caring sciences》2023,37(3):611-627
Background
Social connection is a fundamental human need. Its absence can lead to loneliness and social isolation, adversely impacting health and well-being. Given their regular contact and trusted relationships with older people, practitioners delivering community-based primary care are well-positioned to address this issue. However, their contribution to addressing loneliness and social isolation is unclear.Aim
This integrative review explores the contribution of the primary care workforce to interventions aimed at reducing loneliness and social isolation in community-dwelling older people.Method
Using an integrative review method, Scopus, Web of Science, CINAHL and PubMed were searched for original research published between 2000 and 2022. Fourteen papers reporting 13 primary studies were appraised for methodological quality and included in the review. Data were extracted into a summary table and analysed using thematic analysis.Results
Included studies came from over six countries. Internationally, primary care services have diverse structures, funding and workforces influencing their response to loneliness and social isolation. All but one intervention was multi-component, with ten studies including a group-based activity and three providing primarily individual-level activities. Only six studies reported reductions in loneliness following the intervention. Three themes were identified: characteristics of interventions; implementation context, barriers and facilitators; and differing contributions of primary care practitioners in addressing loneliness and social isolation of older people.Conclusion
There is increasing demand and scope for primary care practitioners to assist lonely and socially isolated older people. It is important to understand how to equip and incentivise these practitioners to routinely identify, assess and respond to lonely and socially isolated older people despite varying implementation contexts. There is a need for further research that explores how the primary care team can be better utilised to deliver effective interventions that reduce the health impacts of loneliness and social isolation. 相似文献90.
Tyrone Gabriel D. Sundiam RN Julia Czarina A. Sy RN Daniel Joseph E. Berdida PhD RN RM Patricia Yssabel R. Talampas RN Hazel Abigail A. Suillan RN Eloisa Andrea V. Sumangil RN Angela Mariz E. Sunga RN Samantha Nicole T. Sy Juco RN Kyle Catherine Talastas RN 《Public health nursing (Boston, Mass.)》2023,40(3):382-393