全文获取类型
收费全文 | 489篇 |
免费 | 26篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 17篇 |
妇产科学 | 45篇 |
基础医学 | 50篇 |
口腔科学 | 1篇 |
临床医学 | 45篇 |
内科学 | 124篇 |
皮肤病学 | 2篇 |
神经病学 | 27篇 |
特种医学 | 18篇 |
外科学 | 96篇 |
综合类 | 2篇 |
预防医学 | 15篇 |
眼科学 | 4篇 |
药学 | 34篇 |
肿瘤学 | 35篇 |
出版年
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 13篇 |
2020年 | 10篇 |
2019年 | 16篇 |
2018年 | 11篇 |
2017年 | 9篇 |
2016年 | 17篇 |
2015年 | 11篇 |
2014年 | 15篇 |
2013年 | 20篇 |
2012年 | 47篇 |
2011年 | 32篇 |
2010年 | 22篇 |
2009年 | 12篇 |
2008年 | 33篇 |
2007年 | 28篇 |
2006年 | 36篇 |
2005年 | 27篇 |
2004年 | 31篇 |
2003年 | 28篇 |
2002年 | 22篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 8篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1957年 | 1篇 |
排序方式: 共有520条查询结果,搜索用时 15 毫秒
21.
Magda Vytrisalova Leos Fuksa Vladimir Palicka Svatopluk Byma Sarka Blazkova Jan Stepan Tereza Hendrychova Jiri Vlcek Petr Pavek 《Central European Journal of Medicine》2014,9(5):687-693
Rationale and objectives
General practitioners (GPs) play an important role in management of patients at risk of osteoporosis (OP). The objectives were to assess (1) knowledge about OP and use of OP clinical guideline in comparison with other information sources and (2) association between the use of individual information sources and knowledge and self-reported quality of care among GPs.Methods
Survey among random sample of Czech GPs was performed to find out their attitudes and role in OP management. The return rate of the postal questionnaire was 38% (525 respondents). Quality of care was assessed using three indicators: suspicion on OP, referral to the specialist and initial check-up.Results
Respondents (median age 52 years, 59% women) had a very good knowledge of several risk factors, while others, namely low body mass index, history of hip fracture in mother and smoking were perceived as risk factors by only 40%, 45% and 55% of respondents, respectively. 10% of GPs stated the correct answer regarding daily calcium intake recommended for postmenopausal women. The OP guideline was considered accessible by 83% of respondents and used repeatedly by 54%. Use of the guideline correlated positively with knowledge score (P < 0.001), while use of each individual other source of information did not. Use of the guideline correlated with all three indicators of quality of care. Use of each other information source correlated only with a maximum of two indicators.Conclusion
We identified areas of insufficient knowledge that should be targeted in educational activities for GPs. It is recommended to further motivate GPs to use their clinical guidelines regularly. 相似文献22.
Aikaterini Dedeilia Stepan M Esagian Ioannis A Ziogas Dimitrios Giannis Ioannis Katsaros Georgios Tsoulfas 《World Journal of Clinical Pediatrics》2020,9(2):7-16
The coronavirus disease 2019 (COVID-19) pandemic has had a major impact on pediatric surgery. The infection is often asymptomatic and atypical in children, while overlapping presentations with other infectious diseases generate additional diagnostic challenges. The high probability of missed pediatric cases and the invasive nature of surgery generate great concern for widespread transmission in this setting. Current guidelines suggest that triage of cases should be made on a case-by-case basis by a multidisciplinary team of experts. Decision-making can be assisted by classifying cases as elective, urgent, or an emergency according to the risks of delaying their surgical management. A workflow diagram should ideally guide the management of all cases from admission to discharge. When surgery is necessary, all staff should use appropriate personal protective equipment, and high-risk practices, such as aerosol-generating tools or procedures, should be avoided if possible. Furthermore, carefully designed organizational protocols should be established to minimize transmission while ensuring the uninterrupted operation of pediatric surgery units. For example, surgical teams can be divided into small weekly rotating groups, and healthcare workers should be continuously monitored for COVID-19 symptoms. Additionally, team protocols in the operating room can optimize communication and improve adherence to personal protective equipment use. Isolated operating rooms, pediatric intensive care units, and surgical wards should be specifically designed for suspected or confirmed COVID-19 cases. Finally, transportation of patients should be minimal and follow designated short routes. All these measures can help mitigate the effects of the COVID-19 pandemic on pediatric surgery units. 相似文献
23.
S. Kaptoge G. Armbrecht D. Felsenberg M. Lunt K. Weber S. Boonen I. Jajic J. J. Stepan D. Banzer W. Reisinger J. Janott G. Kragl C. Scheidt-Nave B. Felsch C. Matthis H. H. Raspe G. Lyritis G Póor R. Nuti T. Miazgowski K. Hoszowski J. Bruges Armas A. Lopes Vaz L. I. Benevolenskaya P. Masaryk J. B. Cannata O. Johnell D. M. Reid A. Bhalla A. D. Woolf C. J. Todd C. Cooper R. Eastell J. A. Kanis T. W. O’Neill A. J. Silman J. Reeve 《Osteoporosis international》2006,17(9):1369-1381
Introduction Vertebral fracture is a strong risk factor for future spine and hip fractures; yet recent data suggest that only 5–20% of subjects with a spine fracture are identified in primary care. We aimed to develop easily applicable algorithms predicting a high risk of future spine fracture in men and women over 50 years of age.Methods Data was analysed from 5,561 men and women aged 50+ years participating in the European Prospective Osteoporosis Study (EPOS). Lateral thoracic and lumbar spine radiographs were taken at baseline and at an average of 3.8 years later. These were evaluated by an experienced radiologist. The risk of a new (incident) vertebral fracture was modelled as a function of age, number of prevalent vertebral fractures, height loss, sex and other fracture history reported by the subject, including limb fractures occurring between X-rays. Receiver Operating Characteristic (ROC) curves were used to compare the predictive ability of models.Results In a negative binomial regression model without baseline X-ray data, the risk of incident vertebral fracture significantly increased with age [RR 1.74, 95% CI (1.44, 2.10) per decade], height loss [1.08 (1.04, 1.12) per cm decrease], female sex [1.48 (1.05, 2.09)], and recalled fracture history; [1.65 (1.15, 2.38) to 3.03 (1.66, 5.54)] according to fracture site. Baseline radiological assessment of prevalent vertebral fracture significantly improved the areas subtended by ROC curves from 0.71 (0.67, 0.74) to 0.74 (0.70, 0.77) P=0.013 for predicting 1+ incident fracture; and from 0.74 (0.67, 0.81) to 0.83 (0.76, 0.90) P=0.001 for 2+ incident fractures. Age, sex and height loss remained independently predictive. The relative risk of a new vertebral fracture increased with the number of prevalent vertebral fractures present from 3.08 (2.10, 4.52) for 1 fracture to 9.36 (5.72, 15.32) for 3+. At a specificity of 90%, the model including X-ray data improved the sensitivity for predicting 2+ and 1+ incident fractures by 6 and 4 fold respectively compared with random guessing. At 75% specificity the improvements were 3.2 and 2.4 fold respectively. With the modelling restricted to the subjects who had BMD measurements (n=2,409), the AUC for predicting 1+ vs. 0 incident vertebral fractures improved from 0.72 (0.66, 0.79) to 0.76 (0.71, 0.82) upon adding femoral neck BMD (P=0.010).Conclusion We conclude that for those with existing vertebral fractures, an accurately read spine X-ray will form a central component in future algorithms for targeting treatment, especially to the most vulnerable. The sensitivity of this approach to identifying vertebral fracture cases requiring anti-osteoporosis treatment, even when X-rays are ordered highly selectively, exceeds by a large margin the current standard of practice as recorded anywhere in the world.This work was presented in part at the 30th European Symposium on Calcified Tissues, 8–12 May 2003, Rome, Italy.A.J. Silman and J. Reeve are the EU Grant holders and Project Leaders. 相似文献
24.
Peripartum cardiomyopathy (PPCM) is rare cardiac complication afflicting women during pregnancy or until 5 months post partum with the typical signs of acute cardiac failure. PPCM is similar to dilated cardiomyopathy (DCM) in terms of symptoms, histopathology and treatment but is characterized by a better outcome with a high rate of spontaneous normalization of left-ventricular size and function. The understanding of the etiology is limited. However, viral myocarditis and autoimmune factors might be involved in the development of PPCM. Clinically, PPCM shows pulmonary symptoms such as dyspnea, tachypnea and coughing. The diagnosis is finally established by echocardiography. It has to be assumed that PPCM is often undetected or misdiagnosed because of the low incidence, the unspecific symptoms and the fact that other pregnancy-related factors have similar clinical appearance. The treatment is also unspecific and similar to DCM and acute cardiac failure. The severity of the disease requires an interdisciplinary approach in a perinatal center with consequent follow-up of the patients for risk stratification including echocardiography. 相似文献
25.
Pop I Petroi C Coroi M Ban C Roiu G Stepan E Nistoran S Hânciu D 《Oftalmologia (Bucharest, Romania : 1990)》2002,54(3):68-71
The purpose of the study is to present the favorable results of YAG: Nd laser capsulotomy for the treatment of secondary opacification of the posterior capsule, in our department. A 3 years retrospective study was performed. For 1440 cataract operations, most of them extracapsular extractions with PMMA IOL placed in the posterior chamber (ciliary sulcus or capsular bag), 285 laser capsulotomies were done. The results are presented statistically, including sex and age distribution, type of cataract surgery and implant, treatment protocol (number of sessions, number of impulses per session, energy per impulse) and complications. The frequency of secondary capsular opacification in our study is 19.78%. It is most important in the age group 60-70 years, where the surgery for cataract is performed more often. Capsulotomy was done after extracapsular extraction with IOL placed in the posterior chamber, but especially after extracapsular extraction without implant placement or with complications that have permitted only the use of an anterior chamber implant. Capsulotomy is performed in only one session in 88% of the cases. The energy per impulse is usually 3-5 mJ and the mean number of impulses per session is 10-30. There are few complications: transient elevation of intraocular pressure in 14.73%, discrete laser marks on the implant in 8.77% and moderate iritis in 1% of the cases. YAG: Nd laser capsulotomy appears to be a safe and efficient method of treating secondary cataract; it improved visual acuity in all cases, if different ocular pathology had not influenced it. 相似文献
26.
27.
28.
MR relaxometry and 1H MR spectroscopy for the determination of iron and metabolite concentrations in PKAN patients 总被引:1,自引:1,他引:0
Hájek M Adamovicová M Herynek V Skoch A Jírů F Krepelová A Dezortová M 《European radiology》2005,15(5):1060-1068
The influence of iron deposits on T2 values and the content of metabolites in the brain of three patients with DNA proved pantothenate kinase-associated neurodegeneration (PKAN, formerly Hallervorden-Spatz syndrome) was studied. An eye-of-the-tiger sign, a typical MR finding for PKAN, was observed in two patients with the same mutation. A hypointensive lesion in a whole globus pallidus was observed in the third patient with the additional mutation. T2 values in the globus pallidus of the patients were about 40% shorter than in controls (71/48 ms in controls vs. patients), which corresponds to the increase of Fe concentration based on the ferritin basis from 17 mg for controls to 48 mg (100 g wet brain weight) in PKAN patients. 1H MR spectroscopy (MRS) has mainly been used to describe neuronal damage represented by decreased NAA (6.4 mmol vs. 9 mmol) and Cr/PCr (7.0 mmol vs. 9.8 mmol) concentrations in the basal ganglia region of the patient group to controls; MRS is much more case-sensitive and describes individual development of the disease as demonstrated in the difference between the spectra of typical PKAN patients (1, 2), and the patient (3) with atypical PKAN development. Any significant changes of metabolite concentration with the exception glutamine, glutamate and GABA were found in the white matter.Part of the study was presented at the ISMRM Meeting, 2004, abstract no. 1423. 相似文献
29.
Kaptoge S Benevolenskaya LI Bhalla AK Cannata JB Boonen S Falch JA Felsenberg D Finn JD Nuti R Hoszowski K Lorenc R Miazgowski T Jajic I Lyritis G Masaryk P Naves-Diaz M Poor G Reid DM Scheidt-Nave C Stepan JJ Todd CJ Weber K Woolf AD Roy DK Lunt M Pye SR O'neill TW Silman AJ Reeve J 《BONE》2005,36(3):387-398
We have previously shown that center- and sex-specific fall rates explained one-third of between-center variation in upper limb fractures across Europe. In this current analysis, our aim was to determine how much of the between-center variation in fractures could be attributed to repeated falling, bone mineral density (BMD), and other risk factors in individuals, and to compare the relative contributions of center-specific BMD vs. center-specific fall rates. A clinical history of fracture was assessed prospectively in 2451 men and 2919 women aged 50-80 from 20 centers participating in the European Prospective Osteoporosis Study (EPOS) using standardized questionnaires (mean follow-up = 3 years). Bone mineral density (BMD, femoral neck, trochanter, and/or spine) was measured in 2103 men and 2565 women at these centers. Cox regression was used to model the risk of incident fracture as a function of the person-specific covariates: age, BMD, personal fracture history (PFH), family hip fracture history (FAMHIP), time spent walking/cycling, number of 'all falls' and falls not causing fracture ('fracture-free') during follow-up, alcohol consumption, and body mass index. Center effects were modeled by inclusion of multiplicative gamma-distributed random effects, termed center-shared frailty (CSF), with mean 1 and finite variance theta (theta) acting on the hazard rate. The relative contributions of center-specific fall risk and center-specific BMD on the incidence of limb fractures were evaluated as components of CSF. In women, the risk of any incident nonspine fracture (n = 190) increased with age, PFH, FAMHIP, > or =1 h/day walking/cycling, and number of 'all falls' during follow-up (all P < 0.074). 'Fracture-free' falls (P = 0.726) and femoral neck BMD did not have a significant effect at the individual level, but there was a significant center-shared frailty effect (theta = 0.271, P = 0.001) that was reduced by 4% after adjusting for mean center BMD and reduced by 19% when adjusted for mean center fall rate. Femoral trochanter BMD was a significant determinant of lower limb fractures (n = 53, P = 0.014) and the center-shared frailty effect was significant for upper limb fractures (theta = 0.271, P = 0.011). This upper limb fracture center effect was unchanged after adjusting for mean center BMD but was reduced by 36% after adjusting for center mean fall rates. In men, risk of any nonspine fracture (n = 75) increased with PFH, fall during follow-up (P < 0.026), and with a decrease in trochanteric BMD [RR 1.38 (1.08, 1.79) per 1 SD decrease]. There was no center effect evident (theta = 0.081, P = 0.096). We conclude that BMD alone cannot be validly used to discriminate between the risk of upper limb fractures across populations without taking account of population-specific variations in fall risk and other factors. These variations might reflect shared environmental or possibly genetic factors that contribute quite substantially to the risk of upper limb fractures in women. 相似文献
30.