全文获取类型
收费全文 | 2011篇 |
免费 | 104篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 155篇 |
妇产科学 | 26篇 |
基础医学 | 207篇 |
口腔科学 | 55篇 |
临床医学 | 184篇 |
内科学 | 630篇 |
皮肤病学 | 23篇 |
神经病学 | 38篇 |
特种医学 | 472篇 |
外科学 | 129篇 |
综合类 | 29篇 |
预防医学 | 56篇 |
眼科学 | 13篇 |
药学 | 56篇 |
中国医学 | 3篇 |
肿瘤学 | 59篇 |
出版年
2022年 | 6篇 |
2021年 | 12篇 |
2020年 | 13篇 |
2019年 | 13篇 |
2018年 | 18篇 |
2017年 | 12篇 |
2016年 | 28篇 |
2015年 | 37篇 |
2014年 | 34篇 |
2013年 | 74篇 |
2012年 | 33篇 |
2011年 | 31篇 |
2010年 | 82篇 |
2009年 | 59篇 |
2008年 | 46篇 |
2007年 | 57篇 |
2006年 | 73篇 |
2005年 | 60篇 |
2004年 | 47篇 |
2003年 | 39篇 |
2002年 | 49篇 |
2001年 | 38篇 |
2000年 | 48篇 |
1999年 | 38篇 |
1998年 | 136篇 |
1997年 | 119篇 |
1996年 | 125篇 |
1995年 | 94篇 |
1994年 | 74篇 |
1993年 | 81篇 |
1992年 | 25篇 |
1991年 | 24篇 |
1990年 | 15篇 |
1989年 | 60篇 |
1988年 | 46篇 |
1987年 | 50篇 |
1986年 | 46篇 |
1985年 | 48篇 |
1984年 | 25篇 |
1983年 | 32篇 |
1982年 | 34篇 |
1981年 | 20篇 |
1980年 | 36篇 |
1979年 | 14篇 |
1978年 | 15篇 |
1977年 | 17篇 |
1976年 | 23篇 |
1975年 | 24篇 |
1971年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有2137条查询结果,搜索用时 11 毫秒
41.
Normal synthesis and expression of endothelial IIb/IIIa in Glanzmann's thrombasthenia 总被引:2,自引:0,他引:2
Glanzmann's thrombasthenia is a bleeding disorder, inherited in an autosomal recessive way and characterized by an absence or deficiency of the platelet glycoprotein (GP) IIb/IIIa complex. Recently, we and others demonstrated that cultured human umbilical vein endothelial cells synthesized a membrane protein complex similar to the platelet GP IIb/IIIa complex. In this article, we demonstrate that endothelial cells isolated from the umbilical vein of a newborn with Glanzmann's thrombasthenia, as compared with normal endothelial cells, show no difference in their ability to synthesize and express this GP IIb/IIIa complex. Our results indicate that Glanzmann's thrombasthenia is not accompanied by an "endotheliopathy." 相似文献
42.
Acute myocardial infarction after simultaneous thrombosis in normal right and left coronary arteries
A 32-year-old male patient with clinical and electrocardiographic evidence of acute myocardial infarction underwent coronary angiographic study. We observed nonocclusive thrombosis simultaneously in right and left anterior descending coronary arteries, without confirmation of spasm or obstructive artery disease in other coronary branches. Documentation of coronary thrombosis in more than one artery is rare, and its pathophysiology is still unknown. With the advent of thrombolytic therapy and immediate coronary angiographic studies in patients with evolving myocardial infarction, it has been possible to confirm the presence of thrombus and the type of coronary disease. In this case, we observed total lysis of both thrombi and the final aspect of "normal" angiographically reperfused coronary arteries. 相似文献
43.
A M Caixeta F S Brito M Rati M A Perin P L da Luz J A Ramires J A Ambrose E E Martinez 《Catheterization and cardiovascular interventions》2000,50(4):398-401
We compared the impact of low and high-pressure balloon inflation on acute and late angiographic results of Multilink stent. Low-pressure balloon inflation (9.5 +/- 1.9 atm) was used in 43 stents and high pressure (17.1 +/- 1.5 atm) in 44. A larger immediate luminal gain was achieved in stents with high-pressure balloon inflation (1.80 +/- 0.26 vs. 1.47 +/- 0.62; P = 0.002), resulting in a larger mean diameter in this group (2.71 +/- 0.37 vs. 2.48 +/- 0.47; P = 0.017). At follow-up, a larger luminal diameter was achieved in the high pressure group (1.93 +/- 0.72 vs. 1.45 +/- 0.66; P = 0.002) and a trend to a lower rate of angiographic restenosis (15% vs. 38%, P = 0.08). 相似文献
44.
Sposito AC Santos RD Hueb W Ventura LI Vinagre CC Ramires JA Maranhão RC 《Atherosclerosis》2002,161(2):447-453
In animal model studies, the uptake of chylomicron remnants after entering in the space of Disse occurs mainly by low-density lipoprotein (LDL) receptor and LDL receptor-related protein (LRP). In subjects, the relative importance of each one of these receptors for the clearance of chylomicron remnants is not fully understood. In our study, LDL cholesterol and apolipoprotein (apo) B were correlated to the plasma kinetics of a chylomicron-like emulsion in 77 subjects (11 women, mean age 58 +/- 12 years) with coronary artery disease (CAD). Their total cholesterol was 227 +/- 25 mg/dl, triglyceride 159 +/- 25 mg/dl, LDL cholesterol 148 +/- 27 mg/dl, HDL cholesterol 40 +/- 9 mg/dl, apo A1 1.80 +/- 0.53 g/l and apo B 1.65 +/- 0.48 g/l. The emulsion was double-labeled with 3H-triolein and 14C-cholesteryl oleate and injected intravenously after 12-h fasting. The decay curves of the radioisotopes were determined from blood samples collected at predetermined intervals during 60 min. A negative correlation between FCR of the emulsion cholesterol esters and LDL cholesterol and apo B plasma concentrations was found (r=-0.4, P=0.005 and r=-0.3, P=0.01, respectively) whereas FCR of the emulsion triglycerides did not correlate with any of the plasma lipids or apolipoprotein parameters. Concluding, in patients with CAD, LDL catabolic pathway significantly influences the removal from plasma of chylomicron remnants. 相似文献
45.
Late coronary artery recanalization effects on left ventricular remodelling and contractility by magnetic resonance imaging. 总被引:3,自引:0,他引:3
Jo?o C Silva Carlos E Rochitte José S Júnior Jeanne Tsutsui Joalbo Andrade Eulógio E Martinez Paulo J Moffa José C Menegheti Roberto Kalil-Filho José F Ramires José C Nicolau 《European heart journal》2005,26(1):36-43
AIMS: To assess the recanalization effects of post-myocardial infarction (MI) on left ventricular (LV) remodelling and contractility in relation to conservative therapy. METHODS AND RESULTS: Thirty-six patients with occluded infarct-related artery between 12 h and 14 days post-anterior MI were randomized to percutaneous coronary intervention (PCI group) or conservative therapy (no-PCI group). Magnetic resonance imaging was performed at enrollment and after 6 months. The left ventricle was divided into infarct, adjacent, and remote segments. There was no difference in relation to LV volume between groups at the 6 month follow-up. Change in LV ejection fraction was favourable to the PCI group: 5.00% vs. -0.76%, P=0.012. Change in circumferential shortening (Ecc) of the remote segments in the PCI group was significantly better than in the no-PCI group: -1.67+/-6.30% vs. 0.29+/-6.02%, P<0.001. Infarct size and LV mass were similar between groups. CONCLUSIONS: Late recanalization improved LV ejection fraction and myocardial contractility in late follow-up, but did not change the ventricular volumes. Improvement in the left ventricle global and regional contractility may benefit the long-term outcome in post-MI patients with sustained patency of the infarct-related artery. 相似文献
46.
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
47.
Alves PM de Freitas EJ Mathias HA da Motta AE Silva Rde C Müller M Almeida SF Stapleton E Timerman S Ramires JA 《Arquivos brasileiros de cardiologia》2001,76(4):310-314
After the incorporation of automated external defibrillators by other airlines and the support of the Brazilian Society of Cardiology, Varig Airlines began the onboard defibrillation program with the initial purpose of equipping wide-body aircrafts frequently used in international flights and that airplanes use in the Rio - S?o Paulo route. With all flight attendants trained, the automated external defibrillation devices were incorporated to 34 airplanes of a total fleet of 80 aircrafts. The devices were installed in the baggage compartments secured with velcro straps and 2 pairs of electrodes, one or which pre-connected to the device to minimize application time. Later, a portable monitor was address to the resuscitation kit in the long flights. The expansion of the knowledge of the basic life support fundamentors and the corrected implantation of the survival chain and of the automated external defibrillators will increase the extense of recovery of cardiorespiratory arrest victims in aircrafts. 相似文献
48.
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49.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179
Introduction
Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.Methods
A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.Results
From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.Conclusions
The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay. 相似文献50.
Demonstration of autoimmune antiphospholipid antibodies (aPA) to negatively charged phospholipids (PL) in an enzyme-linked immunosorbent assay (ELISA) requires the presence of certain phospholipid-binding plasma proteins, eg, beta 2-glycoprotein I. We found a requirement for plasma against the electrically neutral or zwitterionic phospholipid, phosphatidylethanolamine (PE). Two of these PE-binding plasma proteins were identified as high molecular weight kininogen (HMWK) and low molecular weight kininogen (LMWK). We studied anti-PE antibody (aPE) seropositive plasma from 13 patients with SLE and/or recurrent spontaneous abortions by using partially purified kininogens and kininogen binding proteins from adult bovine serum isolated by carboxymethyl (CM)-papain affinity chromatography. Eleven of 13 sera recognized a kininogen-PE complex and/or a kininogen-binding protein- kininogen-PE complex. Some aPE-positive patient sera were shown to recognize highly purified HMWK and LMWK by ELISA only when the kininogens were presented on a PE substrate. These aPE sera did not recognize PE, HMWK, or LMWK when they were presented independently as the sole antigens on the ELISA plates. Other aPE-positive sera that did not react with PE-bound HMWK or LMWK reacted with the CM-papain column eluate when it was bound to PE, which suggests that these aPE recognize factor XI or prekallikrein, which normally bind to HMWK. The aPE ELISA reactivity of two patient sera were inhibited by preincubation of the CM-papain column eluate in the ELISA plate. These data show that most aPE are not specific for PE but require the presence of certain PL- binding plasma proteins that are kininogens or proteins in complex with kininogens. Our studies indicate that aPE bind to different plasma proteins than those implicated in anionic PL, aPA ELISA reactivity. 相似文献