全文获取类型
收费全文 | 1971篇 |
免费 | 131篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 56篇 |
妇产科学 | 48篇 |
基础医学 | 267篇 |
口腔科学 | 100篇 |
临床医学 | 198篇 |
内科学 | 311篇 |
皮肤病学 | 152篇 |
神经病学 | 85篇 |
特种医学 | 231篇 |
外科学 | 254篇 |
综合类 | 81篇 |
预防医学 | 120篇 |
眼科学 | 27篇 |
药学 | 83篇 |
中国医学 | 25篇 |
肿瘤学 | 61篇 |
出版年
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 13篇 |
2019年 | 21篇 |
2018年 | 38篇 |
2017年 | 35篇 |
2016年 | 24篇 |
2015年 | 35篇 |
2014年 | 58篇 |
2013年 | 92篇 |
2012年 | 90篇 |
2011年 | 97篇 |
2010年 | 73篇 |
2009年 | 72篇 |
2008年 | 86篇 |
2007年 | 105篇 |
2006年 | 64篇 |
2005年 | 65篇 |
2004年 | 45篇 |
2003年 | 55篇 |
2002年 | 42篇 |
2001年 | 48篇 |
2000年 | 38篇 |
1999年 | 44篇 |
1998年 | 64篇 |
1997年 | 63篇 |
1996年 | 46篇 |
1995年 | 31篇 |
1994年 | 35篇 |
1993年 | 37篇 |
1992年 | 33篇 |
1991年 | 37篇 |
1990年 | 28篇 |
1989年 | 50篇 |
1988年 | 49篇 |
1987年 | 59篇 |
1986年 | 45篇 |
1985年 | 48篇 |
1984年 | 22篇 |
1983年 | 17篇 |
1982年 | 19篇 |
1981年 | 16篇 |
1980年 | 13篇 |
1979年 | 18篇 |
1978年 | 11篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 9篇 |
1974年 | 8篇 |
1973年 | 12篇 |
排序方式: 共有2108条查询结果,搜索用时 609 毫秒
71.
OBJECTIVE: Advanced life support (ALS) in a cardiac arrest is usually performed by a team consisting of three people. The medical team of a Helicopter Emergency Medical Service (HEMS) often consists of two rescuers only. Due to that reason an algorithm was developed to provide ALS with two people. During the initial phase the rescuer in the over-the-head position provides one man CPR while the second rescuer prepares all advanced measures. When all preparations are complete both rescuers are able to provide ALS. MATERIAL AND METHODS: A computer controlled manikin (Ambu Mega Code Simulator System MCS with online documentation was used to test the entire medical staff during 10 min of persistent VF. RESULTS: The 20 teams were tested. Following data were recorded: no-flow-time 96.4+/-11s (16.1+/-1.8%), chest compression frequency 120.1+/-5.1 min (-1), ventilation frequency=9 min (-1), number of chest compressions per session 1013.7+/-45.9, depth of chest compressions 46.6+/-2.5mm, total number of chest compressions=20,274, total number of ventilations=1893. For ALS measures the following data were recorded: tracheal intubation (TI) was finished after 60.7+/-9.8s, duration of TI : maneuver = 15.7+/-4.4s, end of initial phase=188.9+/-26.3s, i.v. administration of adrenaline after 387.7+/-33.6s, i.v. administration of amiodarone after 507.9+/-36.9s and four shocks after: 138.0+/-15.9, 266.8+/-16.1, 398.0+/-20.1 and 526.8+/-23.6s. CONCLUSION: We proved the feasibility of the algorithm in a manikin setting. Further observations have to prove the algorithm in real CPR situations. 相似文献
72.
GA Antoniou D Murray SA Antoniou G Kuhan F Serracino-Inglott 《Annals of the Royal College of Surgeons of England》2014,96(3):184-189
Introduction
The retrojugular approach for carotid endarterectomy (CEA) has been reported to have the advantages of shorter operative time and ease of dissection, especially in high carotid lesions. Controversial opinion exists with regard to its safety and benefits over the conventional antejugular approach.Methods
A systematic review of electronic information sources was conducted to identify studies comparing outcomes of CEA performed with the retrojugular and antejugular approach. Synthesis of summary statistics was undertaken and fixed or random effects models were applied to combine outcome data.Findings
A total of 6 studies reporting on a total of 740 CEAs (retrojugular approach: 333 patients; antejugular approach: 407 patients) entered our meta-analysis models. The retrojugular approach was found to be associated with a higher incidence of laryngeal nerve damage (odds ratio [OR]: 3.21, 95% confidence interval [CI]: 1.46–7.07). No significant differences in the incidence of hypoglossal or accessory nerve damage were identified between the retrojugular and antejugular approach groups (OR: 1.09 and 11.51, 95% CI: 0.31–3.80 and 0.59–225.43). Cranial nerve damage persisting during the follow-up period was similar between the groups (OR: 2.96, 95% CI: 0.79–11.13). Perioperative stroke and mortality rates did not differ in patients treated with the retrojugular or antejugular approach (OR: 1.26 and 1.28, 95% CI: 0.31–5.21 and 0.25–6.50).Conclusions
Currently, there is no conclusive evidence to favour one approach over the other. Proof from a well designed randomised trial would help determine the role and benefits of the retrojugular approach in CEA. 相似文献73.
74.
Helm HM Hays JC Flint EP Koenig HG Blazer DG 《The journals of gerontology. Series A, Biological sciences and medical sciences》2000,55(7):M400-M405
BACKGROUND: Previous studies have linked higher religious attendance and longer survival. In this study, we examine the relationship between survival and private religious activity. METHODS: A probability sample of elderly community-dwelling adults in North Carolina was assembled in 1986 and followed for 6 years. Level of participation in private religious activities such as prayer, meditation, or Bible study was assessed by self-report at baseline, along with a wide variety of sociodemographic and health variables. The main outcome was time (days) to death or censoring. RESULTS: During a median 6.3-year follow-up period, 1,137 subjects (29.5%) died. Those reporting rarely to never participating in private religious activity had an increased relative hazard of dying over more frequent participants, but this hazard did not remain significant for the sample as a whole after adjustment for demographic and health variables. When the sample was divided into activity of daily living (ADL) impaired and unimpaired, the effect did not remain significant for the ADL impaired group after controlling for demographic variables (hazard ratio [RH] 1.11, 95% confidence interval [CI] 0.91-1.35). However, the increased hazard remained significant for the ADL unimpaired group even after controlling for demographic and health variables (RH 1.63, 95% CI 1.20-2.21), and this effect persisted despite controlling for numerous explanatory variables including health practices, social support, and other religious practices (RH 1.47, 95% CI 1.07-2.03). CONCLUSIONS: Older adults who participate in private religious activity before the onset of ADL impairment appear to have a survival advantage over those who do not. 相似文献
75.
Bishop JF; Matthews JP; Young GA; Szer J; Gillett A; Joshua D; Bradstock K; Enno A; Wolf MM; Fox R 《Blood》1996,87(5):1710-1717
High-dose cytarabine (ara-c) may overcome cytarabine resistance in leukemic blasts. It has been used as a successful salvage and in postremission therapy but not as initial induction treatment. Patients aged 15 to 60 years, presenting with newly diagnosed acute myeloid leukemia (AML) were randomized to receive either high-dose cytarabine, 3 g/m2 12 hourly on days 1, 3, 5, and 7 for 8 doses, daunorubicin 50 mg/m2 days 1 to 3, etoposide 75 mg/m2 days 1 to 7, (HIDAC-3-7) or standard dose cytarabine 100 mg/m2 continuous intravenous infusion for 7 days with daunorubicin and etoposide at the same dose and schedule as above (7-3-7). Patients could receive a second or third induction course if complete remission (CR) was not achieved. All patients received the same postinduction consolidation therapy (5-2-5) for 2 courses. Eligible patients had no prior chemotherapy or myelodysplastic disease. Patients have been followed for a median of 4.5 years. Of 301 patients treated, complete response (CR) was achieved in 71% with HIDAC- 3-7 and 74% with 7-3-7. For patients in CR, the estimated median remission duration was 45 months with HIDAC-3-7 and 12 months with 7-3- 7 (P = .0005 univariate analysis, P = .0004 multivariate analysis). The estimated percentage of patients relapse free 5 years after achieving a CR was 49% on HIDAC-3-7 and 24% on 7-3-7. Patients in CR tended to survive longer with HIDAC-3-7 but there were no overall survival differences between the two arms. HIDAC-3-7 was associated with significantly more toxicity in induction with more leukopenia, thrombocytopenia, nausea, and vomiting and eye toxicity (all P < .001) but a similar incidence of severe central nervous system and cerebellar toxicity compared to 7-3-7. The consolidation treatment was the same in both arms but caused significantly more leukopenia and thrombocytopenia in patients previously treated with HIDAC-3-7 induction (P < .0001). We conclude that a dose-effect exists for cytarabine in AML and that HIDAC- 3-7 prolongs remission duration and disease-free survival and is tolerable when used as initial induction therapy in patients with de novo AML. 相似文献
76.
GA FitzGerald 《Circulation》1998,98(22):2363-2364
77.
Fibronectin binding to thrombin-stimulated platelets: evidence for fibrin(ogen) independent and dependent pathways 总被引:2,自引:0,他引:2
Plasma fibronectin binds in a specific and saturable manner to thrombin- stimulated platelets. gamma-Thrombin stimulated 80% as much fibronectin binding to platelets as alpha-thrombin with conversion of less than or equal to 1% of platelet fibrinogen to fibrin. Afibrinogenemic and normal platelets bound similar quantities of fibronectin in the presence of calcium or magnesium-ethylene glycol tetra-acetic acid (EGTA). These observations indicate that fibronectin can interact with platelets without involvement of fibrin or fibrinogen. Nevertheless, two different effects of fibrin(ogen) on fibronectin binding were observed. First, exogenous fibrinogen inhibited fibronectin binding to thrombin-stimulated platelets. This inhibition was unidirectional, as fibronectin did not inhibit fibrinogen binding to ADP or thrombin- stimulated cells. Second, formaldehyde-fixed cells with surface- associated fibrin bound significant quantities of fibronectin. This interaction required calcium and did not occur on fixed cells with or without surface-bound fibrinogen. A portion of the ligand bound to fixed cells with surface-associated fibrin was modified to form a derivative with a molecular weight identical to that of the fibronectin subunit cross-linked to the alpha-chain of fibrin. This high mol wt derivative was also observed to a variable extent with living cells in the presence of magnesium or calcium but not in the presence of magnesium-EGTA. Thus, fibronectin binds to platelets by at least two mechanisms: (1) a fibrin(ogen)-independent pathway that requires divalent ions and is inhibited by exogenous fibrinogen; and (2) a fibrin-dependent pathway with an absolute calcium requirement. With nonaggregated, thrombin-stimulated platelets, the former pathway appears to predominate. 相似文献
78.
Scott K. Okamoto PhD Susana Helm PhD Suzanne Pel BA Latoya L. McClain MSW Amber P. Hill Janai K. P. Hayashida 《The journal of behavioral health services & research》2014,41(1):8-19
This article describes the relevance of a culturally grounded approach toward drug prevention development for indigenous youth populations. This approach builds drug prevention from the “ground up” (i.e., from the values, beliefs, and worldviews of the youth that are the intended consumers of the program) and is contrasted with efforts that focus on adapting existing drug prevention interventions to fit the norms of different youth ethnocultural groups. The development of an empirically based drug prevention program focused on rural Native Hawaiian youth is described as a case example of culturally grounded drug prevention development for indigenous youth; the impact of this effort on the validity of the intervention and on community engagement and investment in the development of the program are discussed. Finally, implications of this approach for behavioral health services and the development of an indigenous prevention science are discussed. 相似文献
79.
Dr. B. Hossfeld OFA T. Holsträter S. Holsträter D. Rein F. Josse L. Lampl M. Helm 《Der Anaesthesist》2014,63(5):439-450
Blast injuries may result from a variety of causes but the biomechanical impact and pathophysiological consequences do not differ between domestic or industrial accidents or even terrorist attacks. However, this differentiation relevantly affects the tactical procedures of the rescue teams. Focusing on further detonations, top priority is given to the personal safety of all rescue workers. The rareness of blast injuries in a civilian setting results in a lack of experience on the one hand but on the other hand the complexity of blast injuries to the human body places high demands on the knowledge and skills of the entire rescue team for competent treatment. The purpose of this article is to explain the physicochemical principles of explosions and to convey tactical and medical knowledge to emergency medical services. 相似文献
80.