全文获取类型
收费全文 | 3418篇 |
免费 | 191篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 95篇 |
妇产科学 | 72篇 |
基础医学 | 516篇 |
口腔科学 | 52篇 |
临床医学 | 256篇 |
内科学 | 945篇 |
皮肤病学 | 51篇 |
神经病学 | 390篇 |
特种医学 | 82篇 |
外科学 | 249篇 |
综合类 | 6篇 |
一般理论 | 3篇 |
预防医学 | 220篇 |
眼科学 | 22篇 |
药学 | 254篇 |
中国医学 | 6篇 |
肿瘤学 | 391篇 |
出版年
2024年 | 5篇 |
2023年 | 27篇 |
2022年 | 56篇 |
2021年 | 98篇 |
2020年 | 62篇 |
2019年 | 55篇 |
2018年 | 84篇 |
2017年 | 69篇 |
2016年 | 67篇 |
2015年 | 95篇 |
2014年 | 112篇 |
2013年 | 159篇 |
2012年 | 265篇 |
2011年 | 239篇 |
2010年 | 118篇 |
2009年 | 116篇 |
2008年 | 218篇 |
2007年 | 255篇 |
2006年 | 226篇 |
2005年 | 198篇 |
2004年 | 197篇 |
2003年 | 157篇 |
2002年 | 137篇 |
2001年 | 47篇 |
2000年 | 38篇 |
1999年 | 53篇 |
1998年 | 38篇 |
1997年 | 20篇 |
1996年 | 28篇 |
1995年 | 26篇 |
1994年 | 20篇 |
1993年 | 13篇 |
1992年 | 42篇 |
1991年 | 31篇 |
1990年 | 23篇 |
1989年 | 29篇 |
1988年 | 17篇 |
1987年 | 32篇 |
1986年 | 22篇 |
1985年 | 23篇 |
1984年 | 14篇 |
1983年 | 17篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1979年 | 16篇 |
1978年 | 7篇 |
1976年 | 4篇 |
1974年 | 9篇 |
1970年 | 3篇 |
1966年 | 4篇 |
排序方式: 共有3622条查询结果,搜索用时 15 毫秒
1.
Chiara Tanzi Gaia Fallani Francesco Magnani Giovanni Marozza Silvia Pizzarotti Bruno Zoppi Davide Lazzeroni Lorenzo Brambilla Paolo Coruzzi Luca Moderato 《La Medicina del lavoro》2020,111(2):107
Background:Cardiovascular diseases (CVD), particularly the ischemic heart disease, are a growing public health issue. In addition, the return to work after an acute cardiovascular attack represents a complex challenge.Objectives:To evaluate utility and safety of cardiopulmonary exercise testing (CPET), particularly performed “on site”, to promote a return to work in line with the residual working capacity.Methods:Fifty-nine workers affected by a major cardiovascular event, aged 18-63 years, have been enrolled between 2015 and 2018. All the patients underwent a CPET in outpatient clinic. Eleven workers also underwent the “on site” CPET, recorded during their working activities.Results:Outpatient clinic CPET outcomes (i.e. normal, mild impairment or moderate/severe impairment of cardiopulmonary function) were associated with the subjective perception of workers’ health status after returning to work. The “on site” CPET was found to be safe and reliable to promote a personalized return to work of patients. In 7 out of 11 patients, the values of O2 consumption (VO2) during the working activity were higher than 40% of VO2 max as obtained from laboratory CPET.Conclusions:This study provides evidence for safety and usefulness of “on site” CPET for a personalized statement of fitness for work. This may facilitate the job retention of patients characterized by a high risk of unnecessary job loss. The use of CPET represents a first step of energy expenditure evaluation associated with specific working tasks.Key words: Acute coronary syndrome, cardiopulmonary exercise testing, return to work 相似文献
2.
Accuracy evaluation of image registration and segmentation tools used in conformal treatment planning of prostate cancer. 总被引:1,自引:0,他引:1
Stefania Pallotta Marta Bucciolini Serenella Russo Cinzia Talamonti Talamonti Cinzia Giampaolo Biti 《Computerized medical imaging and graphics》2006,30(1):1-7
Segmentation and registration tools are commonly used in radiotherapy for target and at risk organs localisation. In this work the performances of three different segmentation tools and of a surface matching registration technique, used on computed tomography (CT) and magnetic resonance (MR) images for the treatment planning of conformal prostate carcinoma, are studied. The accuracy of the segmentation and registration tools was evaluated by phantom experiment and on patient data, respectively. A preliminary estimate of MR image distortion was also performed. 相似文献
3.
4.
Hemoglobin adducts of benzo[a]pyrene diolepoxide in newspaper vendors: association with traffic exhaust 总被引:1,自引:0,他引:1
Pastorelli Roberta; Restano Jolanda; Guanci Marco; Maramonte Monica; Magagnotti Cinzia; Allevi Riccardo; Lauri Davide; Fanelli Roberto; Airoldi Luisa 《Carcinogenesis》1996,17(11):2389-2394
Benzo[a]pyrene diol epoxide adducts with hemoglobin (Hb) weremeasured to detect human exposure to environmental benzo[a]pyrenefrom traffic exhaust. Benzo[a]pyrene tetrahydrotetrols (BPTs)released from Hb after acid hydrolysis were quantitated by gaschromatography-mass spectrometry after immunoaffinity chromatography.Fifty three newspaper vendors were enrolled. The median adductconcentration was 0.3 fmol BPTs/mg Hb in high density traffic-exposedvendors and 相似文献
5.
Luciano Potena Francesco Grigioni Gaia Magnani Paolo Ortolani Fabio Coccolo Simonetta Sassi Koen Koessels Cinzia Marrozzini Antonio Marzocchi Samuela Carigi Anna C. Musuraca Antonio Russo Carlo Magelli Angelo Branzi 《American journal of transplantation》2005,5(9):2258-2264
Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia. 相似文献
6.
P Ninfali L Rossi L Baronciani B Tirillini C Ropars M Magnani 《Alcohol and alcoholism (Oxford, Oxfordshire)》1992,27(1):19-23
Blood levels of acetaldehyde (ACh), ethanol and acetone were investigated in mice treated with ethanol for 6 months and receiving compatible erythrocytes (RBCs) overloaded with aldehyde dehydrogenase (AlDH). Following an acute dose of ethanol, ACh levels were significantly lower in these animals than in alcohol-treated mice receiving AlDH-unloaded RBCs, and were similar to the ACh levels of normal mice. The peak ethanol concentration was higher in normal mice than in both groups of alcohol-treated animals, while acetone concentrations were not significantly different in the three groups of animals. 相似文献
7.
G Piovaccari A Marzocchi C Marrozzini F M Picchio M Sanguinetti B Magnani 《Giornale italiano di cardiologia》1986,16(6):527-530
The technique used in percutaneous embolization of a Blalock-Taussig shunt in a 35-year-old male is described. After selective catheterization of the left subclavian artery leading to the shunt, some spring coils were inserted which completely occluded the shunt. The choice of occluding material is discussed. 相似文献
8.
C Borghi C Magelli S Boschi F V Costa M Capelli E Varani B Magnani E Ambrosioni 《Journal of clinical pharmacology》1989,29(12):1077-1082
In 14 patients with congestive heart failure (CHF) of various grade (NYHA class 2-4) the effects of zofenopril calcium (SQ 26,991) on blood pressure and forearm circulation were studied by venous occlusion plethysmography. Changes in plasma renin activity (PRA), aldosterone, Atrial natriuretic factor (ANF) and arginine-vasopressin (AVP) were also measured. Two hours after oral administration of 7.5 mg of zofenopril we observed a decrease in blood pressure, heart rate, and forearm vascular resistance along with an increase in venous distensibility. Zofenopril also decreased ANP levels in a manner directly related to peripheral venodilatation (r = .64; P less than .05) and modified arginine-vasopressin (AVP) proportionally to the fall in blood pressure observed in response to drug administration (%SBP/%AVP: r = .64, P less than .05; %DBP/%AVP: r = .67, P less than .05). Hemodynamic and humoral responses to zofenopril occurred without any significant unwanted adverse reaction, even in patients with greater pressor reduction. We conclude that oral acute zofenopril administration, in patients with congestive heart failure, causes an arterial and venous forearm vasodilatation which is probably involved in the acute changes in plasma levels of ANF and AVP observed after drug administration. 相似文献
9.
Pleural malignant mesothelioma and non-occupational exposure to asbestos in Casale Monferrato, Italy. 总被引:6,自引:3,他引:3 下载免费PDF全文
C Magnani B Terracini C Ivaldi M Botta A Mancini A Andrion 《Occupational and environmental medicine》1995,52(6):362-367
OBJECTIVES--To assess and quantify the occurrence of pleural malignant mesotheliomas in people who neither experienced occupational exposure to asbestos nor were married to (or known to live with) workers exposed to asbestos in the workplace. The study was conducted in the area of the local health authority of Casale Monferrato, in north western Italy, where a large factory that produced asbestos cement was active up to 1985. No other major activities related to asbestos have ever been present in the area. METHODS--A retrospective survey covering the period 1980 to 1991 identified 126 incident pleural malignant mesotheliomas histologically diagnosed among residents in the local health authority (population at the 1981 census 98,000). Submission of 83 of 95 cases diagnosed during 1980-9 for revision by a panel of five expert pathologists led to the exclusion of 21. The 31 cases diagnosed in 1990-1 were not submitted for revision. For 64 of the 105 retained cases, information derived from different sources (rosters of the employees in the asbestos cement factory dated back to 1907, list of their spouses, clinical records) did not suggest occupational or paraoccupational exposure to asbestos. RESULTS--Incidence excludes cases for which there was some suggestion of occupational or paraoccupational exposure to asbestos. Incidence of histologically confirmed malignant mesothelioma among residents in the local health authority (annual x 100,000; age adjusted) was 4.2 in men and 2.3 in women (based on 26 and 18 cases respectively). In both sexes, rates in 1985-9 were higher than in the previous quinquennium. Corresponding estimates for 1990-1 (based on unrevised diagnoses) suggest similar rates in men and women. CONCLUSION--Rate ratios which are four to six times those measured by conventional Italian cancer registries can hardly be totally explained by bias produced by lack of recognition of occupational or paraoccupational exposure. The problem of proving this type of negative data is common to other circumstances of alleged cancer clusters of environmental (non occupational) origin. 相似文献
10.
M. E. J. van Velthoven M. D. de Smet R. O. Schlingemann M. Magnani F. D. Verbraak 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(9):1119-1123
Background Evaluating the presence of leakage on fluorescein angiography (FA) in patients with age-related macular degeneration (AMD) retreated with photodynamic therapy (PDT) can be difficult. New diagnostic tools such as optical coherence tomography (OCT) might help to optimize PDT management.Methods Thirty AMD patients scheduled for regular follow-up FA in conjunction with PDT treatment were also scanned with OCT. Follow-up data at 9 months were retrieved from the patients’ medical records. Inter-observer agreement [kappa (κ) coefficient] for the presence of leakage on FA, for OCT parameters for leakage, and agreement between FA and OCT evaluations were calculated. The indication for retreatment was evaluated using the leakage analysis based on FA alone, OCT alone, and both examinations combined, and compared to the actual follow-up of the patients at 9 months.Results Agreement between the two observers for the presence of leakage on FA was moderate (κ=0.51). OCT agreement between the two observers for the presence of leakage was good (κ=0.85). Agreement between FA and OCT for the presence of leakage was poor (κ=0.16). Follow-up data at 9 months on all patients were analyzed. Seven out of 30 patients were not retreated at the time of examination, and four of these patients (57%) remained stable without further treatment. Twenty-three patients did receive a PDT treatment at the time of examination; and eight of these patients did not show leakage on OCT, and five of these patients (62%) remained stable without additional treatment. In contrast, only three out of 15 patients (20%) with leakage on both FA and OCT remained stable during this 9 month follow-up period.Conclusions Inter-observer agreement for the presence of leakage was moderate for FA and good for OCT. There was considerable disagreement between leakage as judged by OCT and by FA. OCT could be of help in the decision regarding PDT retreatment. Assuming that 57% of the patients without leakage either on FA or OCT would remain stable without retreatment, the rate of probable ineffective retreatment could be reduced from 35% to 20%.There was no financial support for this study. The authors have full access to the data and will allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review the data if requeste.d 相似文献