全文获取类型
收费全文 | 2698篇 |
免费 | 158篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 167篇 |
妇产科学 | 26篇 |
基础医学 | 286篇 |
口腔科学 | 75篇 |
临床医学 | 269篇 |
内科学 | 713篇 |
皮肤病学 | 29篇 |
神经病学 | 123篇 |
特种医学 | 502篇 |
外国民族医学 | 1篇 |
外科学 | 252篇 |
综合类 | 41篇 |
预防医学 | 105篇 |
眼科学 | 45篇 |
药学 | 134篇 |
中国医学 | 3篇 |
肿瘤学 | 102篇 |
出版年
2022年 | 10篇 |
2021年 | 24篇 |
2020年 | 23篇 |
2019年 | 20篇 |
2018年 | 43篇 |
2017年 | 33篇 |
2016年 | 45篇 |
2015年 | 48篇 |
2014年 | 53篇 |
2013年 | 93篇 |
2012年 | 64篇 |
2011年 | 79篇 |
2010年 | 98篇 |
2009年 | 82篇 |
2008年 | 79篇 |
2007年 | 67篇 |
2006年 | 98篇 |
2005年 | 82篇 |
2004年 | 71篇 |
2003年 | 63篇 |
2002年 | 63篇 |
2001年 | 67篇 |
2000年 | 69篇 |
1999年 | 59篇 |
1998年 | 148篇 |
1997年 | 126篇 |
1996年 | 129篇 |
1995年 | 97篇 |
1994年 | 75篇 |
1993年 | 83篇 |
1992年 | 42篇 |
1991年 | 32篇 |
1990年 | 32篇 |
1989年 | 88篇 |
1988年 | 64篇 |
1987年 | 68篇 |
1986年 | 55篇 |
1985年 | 58篇 |
1984年 | 31篇 |
1983年 | 37篇 |
1982年 | 37篇 |
1981年 | 30篇 |
1980年 | 43篇 |
1979年 | 24篇 |
1978年 | 15篇 |
1977年 | 20篇 |
1976年 | 26篇 |
1975年 | 28篇 |
1971年 | 6篇 |
1969年 | 6篇 |
排序方式: 共有2878条查询结果,搜索用时 15 毫秒
91.
James R Bell Antonia JA Raaijmakers Johannes V Janssens Lea MD Delbridge 《Clinical and experimental pharmacology & physiology》2015,42(12):1327-1332
Control of cardiomyocyte cytosolic Ca2+ levels is crucial in determining inotropic status and ischemia/reperfusion stress response. Responsive to fluctuations in cellular Ca2+, Ca2+/calmodulin‐dependent protein kinase II (CaMKII) is a serine/threonine kinase integral to the processes regulating cardiomyocyte Ca2+ channels/transporters. CaMKII is primarily expressed either in the δB or δC splice variant forms, which may mediate differential influences on cardiomyocyte function and pathological response mechanisms. Increases in myocyte Ca2+ levels promote the binding of a Ca2+/calmodulin complex to CaMKII, to activate the kinase. Activity is also maintained through a series of post‐translational modifications within a critical region of the regulatory domain of the protein. Recent data indicate that the post‐translational modification status of CaMKIIδB/δC variants may have an important influence on reperfusion outcomes. This study provided the first evidence that the specific type of CaMKII post‐translational modification has a role in determining target selectivity of downstream Ca2+ transporters. The study was also able to demonstrate that the phosphorylated form of CaMKII closely co‐localizes with CaMKIIδB in the nuclear/myofilament fraction, contrasting with a co‐enrichment of oxidized CaMKII in the membrane fraction with CaMKIIδC. It has also been possible to conclude that a hyper‐phosphorylation of CaMKII (Thr287) in reperfused hearts represents a hyper‐activation of the CaMKIIδB, which exerts anti‐arrhythmic actions through an enhanced capacity to selectively increase sarcoplasmic reticulum Ca2+ uptake and maintain cytosolic Ca2+ levels. This suggests that suppression of global CaMKIIδ may not be an efficacious approach to developing optimal pharmacological interventions for the vulnerable heart. 相似文献
92.
Mannucci PM; Lombardi R; Castaman G; Dent JA; Lattuada A; Rodeghiero F; Zimmerman TS 《Blood》1988,71(1):65-70
When normal volunteers or patients with type I von Willebrand disease (VWD) are given desmopressin (DDAVP), a set of larger-than-normal (supranormal) von Willebrand factor (VWF) multimers, similar to those present in VWF-containing cells such as platelets megakaryocytes and endothelial cells, appear transiently in postinfusion plasma. In two kindreds with mild lifelong bleeding symptoms transmitted as an autosomal dominant trait, all ten symptomatic members (but none of the five asymptomatic members) had a supranormal multimeric structure for plasma VWF, apparently identical to that seen for postdesmopressin normal plasma. Plasma factor VIII coagulant activity (VIII:C), VWF antigen (VWF:Ag), ristocetin-induced platelet agglutination, and ristocetin cofactor (RiCof) activity were low. Platelet VWF:Ag and RiCof levels (tested for three patients only) were normal. Bleeding times were normal or slightly prolonged. The patients' platelet multimeric structure was the same as that for normal platelets. After desmopressin infusion the plasma VWF multimeric structure remained supranormal as for preinfusion plasma, with VIII:C VWF:Ag and RiCof increasing markedly over baseline values and disappearing at a normal rate. Examination of the VWF subunit composition from three of these patients indicated that proteolytic processing of their VWF did not differ from normal. This study describes the first variant of VWD with a supranormal multimeric structure. 相似文献
93.
Jean-Jacques Lemaire Alexandra Golby William M. Wells III Sonia Pujol Yanmei Tie Laura Rigolo Alexander Yarmarkovich Steve Pieper Carl-Fredrik Westin Ferenc Jolesz Ron Kikinis 《Brain topography》2013,26(3):428-441
Traditional models of the human language circuitry encompass three cortical areas, Broca’s, Geschwind’s and Wernicke’s, and their connectivity through white matter fascicles. The neural connectivity deep to these cortical areas remains poorly understood, as does the macroscopic functional organization of the cortico-subcortical language circuitry. In an effort to expand current knowledge, we combined functional MRI (fMRI) and diffusion tensor imaging to explore subject-specific structural and functional macroscopic connectivity, focusing on Broca’s area. Fascicles were studied using diffusion tensor imaging fiber tracking seeded from volumes placed manually within the white matter. White matter fascicles and fMRI-derived clusters (antonym-generation task) of positive and negative blood-oxygen-level-dependent (BOLD) signal were co-registered with 3-D renderings of the brain in 12 healthy subjects. Fascicles connecting BOLD-derived clusters were analyzed within specific cortical areas: Broca’s, with the pars triangularis, the pars opercularis, and the pars orbitaris; Geschwind’s and Wernicke’s; the premotor cortex, the dorsal supplementary motor area, the middle temporal gyrus, the dorsal prefrontal cortex and the frontopolar region. We found a functional connectome divisible into three systems—anterior, superior and inferior—around the insula, more complex than previously thought, particularly with respect to a new extended Broca’s area. The extended Broca’s area involves two new fascicles: the operculo-premotor fascicle comprised of well-organized U-shaped fibers that connect the pars opercularis with the premotor region; and (2) the triangulo-orbitaris system comprised of intermingled U-shaped fibers that connect the pars triangularis with the pars orbitaris. The findings enhance our understanding of language function. 相似文献
94.
95.
96.
Vach M. Attenberger U. I. Pieper C. C. 《Cardiovascular and interventional radiology》2021,44(2):333-335
CardioVascular and Interventional Radiology - 相似文献
97.
98.
99.
Nemandra Sandiford SK Muirhead-Allwood JA Skinner 《Indian Journal of Orthopaedics》2015,49(6):595-601
Background:
Hip resurfacing arthroplasty (HRA) is primarily indicated for young, active patients with disabling coxarthrosis who wish to remain active and return to sports after surgery. Relatively few prospective studies have assessed return to sporting activity and impact of gender and age on this.Materials and Methods:
Seventy-nine consecutive patients treated with HRA were included. Patients were reviewed clinically and radiologically. Function was assessed using the modified University of California Los Angeles (UCLA) activity score. The Oxford, Harris and WOMAC hip scores were calculated.Results:
Average age at the time of surgery was 54.9 years (range 34.5–73.6 years). Average preoperative and postoperative UCLA scores were 4 and 7.6 respectively. Patients were involved in 2 (0–4) sporting activities preoperatively and 2 (0–5) postoperatively. Preoperative and postoperative Oxford Hip Scores, Harris Hip Score and WOMAC scores were 40, 46 and 51 and 16, 94 and 3 respectively (P < 0.0001). Patients returned to sports at an average of 3 months postoperatively.Conclusion:
Patients were able to return to sports by 3 months and perform the same number of activities at preoperative intensity. Activity levels are maintained up to the medium term with few complications. 相似文献100.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179