全文获取类型
收费全文 | 2036篇 |
免费 | 143篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 96篇 |
妇产科学 | 14篇 |
基础医学 | 288篇 |
口腔科学 | 216篇 |
临床医学 | 214篇 |
内科学 | 315篇 |
皮肤病学 | 24篇 |
神经病学 | 203篇 |
特种医学 | 78篇 |
外科学 | 372篇 |
综合类 | 5篇 |
一般理论 | 3篇 |
预防医学 | 77篇 |
眼科学 | 43篇 |
药学 | 129篇 |
中国医学 | 2篇 |
肿瘤学 | 107篇 |
出版年
2023年 | 13篇 |
2022年 | 5篇 |
2021年 | 26篇 |
2020年 | 23篇 |
2019年 | 27篇 |
2018年 | 36篇 |
2017年 | 33篇 |
2016年 | 43篇 |
2015年 | 43篇 |
2014年 | 68篇 |
2013年 | 99篇 |
2012年 | 133篇 |
2011年 | 145篇 |
2010年 | 89篇 |
2009年 | 102篇 |
2008年 | 156篇 |
2007年 | 159篇 |
2006年 | 145篇 |
2005年 | 145篇 |
2004年 | 144篇 |
2003年 | 132篇 |
2002年 | 119篇 |
2001年 | 20篇 |
2000年 | 16篇 |
1999年 | 22篇 |
1998年 | 23篇 |
1997年 | 22篇 |
1996年 | 17篇 |
1995年 | 23篇 |
1994年 | 16篇 |
1993年 | 13篇 |
1992年 | 12篇 |
1991年 | 14篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 13篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 9篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1978年 | 4篇 |
1974年 | 5篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1969年 | 3篇 |
1967年 | 3篇 |
排序方式: 共有2194条查询结果,搜索用时 390 毫秒
1.
Urs Kalbermatten 《Psychotherapie Forum》2006,14(1):3-6
Reflecting on the attitude to one's own aging process and a deeper wrestling with one's own purpose, as well as contemplating the life situation of aging seniors forms an essential access to the understanding of their experience. The structure of the aging process has changed and we need new visions with an emphasis on realizing a new, conscious, independent phase of life. While exploring the past offers an important resource in navigating through the aging process, persons with no vision of the future or who continue to define themselves by no longer viable roles and functions are at risk for developing psychological damage and disorders. Therefore, it is a central tenant in psychotherapy with seniors to combine work on the past with actual challenges in the present such as reduction in physical and mental capacities, the possibility of going into a retirement or nursing home, redefining one's identity after retirement and dealing with one's mortality. 相似文献
2.
Franz F Immer Urs Hagen Pascal A Berdat Friedrich S Eckstein Thierry P Carrel 《European journal of cardio-thoracic surgery》2005,27(4):654-657
OBJECTIVES: Prompt diagnosis of subsequent dilatation of the dissected aorta is crucial to reduce late mortality in these patients. This study focuses on risk factors for dilatation of the aorta after type A aortic dissection (AADA) affecting a normal-sized or slightly dilated aorta. METHODS: Overall 531 CT scans were analysed. Patients were included in the study if at least 3 CT scans were available after operative repair. 64 patients (59.8%) out of 107 patients full-field the inclusion criteria. Volumetric analyses of the aorta were performed. Patients were divided in 3 groups: group A included 26 patients (40.6%) without progression of the aortic diameter, group 2, 27 patients (42.2%) with slight progression and group 3, 11 patients (17.2%) with important progression, requiring surgery in 9 patients (81.8%). Risk-factors for progression of the aortic size were analysed and compared between the groups. RESULTS: Patients from group 3 were younger 57.7+/-13.4 vs. 61.9+/-11.6 in group 1 (P<0.05) and were more frequent female (45.4 vs. 23.1%; P<0.05). Dissection of the supraaortic branches (100 vs. 80.8%; P<0.05), the presence of preoperative cerebral, visceral or peripheral malperfusion (54.6 vs. 26.9%; P<0.05) and contrast enhancement in the false lumen during the follow-up (72.7 vs. 57.7%; P=0.07) were additional risk factors for late aortic dilatation in these patients. CONCLUSIONS: Acute type A aortic dissection in younger patients, involving the supraaortic branches and/or combined with malperfusion syndrome favour secondary dilatation. A close follow-up is mandatory to prevent acute complications of the diseased downstream aorta following repair of a AADA. 相似文献
3.
4.
Axel Zöllner Urs Belser On behalf of Working Group 《Clinical oral implants research》2007,18(S3):114-116
Abstract: In order to evaluate the level of evidence of factors influencing the survival of reconstructions, systematic reviews of the relevant literature were prepared by a group of rapporteurs. The review papers were circulated to the members of the group before the conference and formed the basis for group and panel discussions. Subsequently, modifications were added to the review papers, and suggestions for consensus statements concerning the following topics were prepared and again critically reviewed in the group and in the plenum: Impact of (i) periodontal disease on the survival of tooth-supported reconstructions, (ii) post-surgical factors as supportive therapy on the survival of implant supported reconstructions, (iii) technical and/or biological complications on the survival of different types of reconstructions, (iiii) material choice for reconstructions on the survival of single crowns and fixed dental prostheses. 相似文献
5.
6.
DMD Arthur Demisch Profesor DDS Odont. Dr. Bengt Ingervall Professor Chairman DMD Urs Thüer Associate Professor 《American journal of orthodontics and dentofacial orthopedics》1992,102(6):509-518
The effect of the treatment of Angle Class II, Division 2 malocclusion was studied in 22 children by x-ray cephalometry and by recording the relation between the retruded and the intercuspal mandibular positions. The treatment was performed in three phases. In the first phase the upper incisors were proclined, and the deep bite was corrected with an upper removable plate. In the second phase the distal occlusion was corrected with an activator. The result was retained in the third phase with a second activator designed for retention. The relation between the retruded (RCP) and the intercuspal (ICP) mandibular positions was recorded with wax bites and dental casts mounted in a modified gnathothesiometer. The anteroposterior distance between RCP and ICP was large before the start of the treatment. The distance was unchanged after proclination of the upper incisors and correction of the deep bite but decreased after correction of the distal occlusion and increased again somewhat during the retention phase. The proclination of the upper incisors and the correction of the deep bite (phase one of the treatment) did not result in mandibular anterior positioning. This fact and the results of the recordings of the relation between RCP and ICP were interpreted as evidence that the mandible is not posteriorly displaced in Class II, Division 2 malocclusion. 相似文献
7.
8.
Urs Brägger Urs Häfeli Beat Huber Christoph H. F. Hämmerle Niklaus P. Lang 《Clinical oral implants research》1998,9(4):218-224
In most of the studies on long-term radiographic evaluations of crestal bone levels adjacent to dental implants, no baseline radiographs taken immediately post-surgically had been obtained.The aim of this study was to test the reproducibility of a simple radiographic method for linear measurements of changes in bone levels and to evaluate changes in crestal bone levels adjacent co non-submerged ITI® implants 1 year following the surgical procedure. From 128 patients enrolled in a clinical and radiographic longitudinal study 40 patients also had radiographs taken immediately postsurgically. They were, however, not obtained as “identical” images. The radiographs were mounted onto slides and projected on a screen. Mesially and distally from 57 implants triplicate linear measurements of the distance implant shoulder to bone crest were taken, using known dimensions of the implants as internal reference distances. The median difference of 213 (out of 228 possible) duplicate measurements was 0.00 mm (ranging from ?1.72 mm to +1.47 mm when comparing the second co the third reading). Some 81% of the double measurements were within ±0.5 mm and the precision was 0.30 mm. In the immediate postoperative radiographs the median mesial bone level was located at 2.07 mm (distally 2.19 mm) from the implant shoulder. A statistically significant amount of bone loss in the first year was observed mesially (median=?0.78 mm) and distally (0.85 mm)(Wilcoxon matched pairs signed rank test ±0.001). No statistically significant influence of the implant location, the implant length, type of the implant (screw; cylinder) was observed (Kruskal-Wallis P>0.05).The age of the patients was not correlated significantly to the amount of bone loss observed. In conclusion, methodological limitations existed when evaluating linear bone changes in non-identical radiographs using reference dimensions of the implants. The amount of postsurgical bone loss estimated in other studies was confirmed when using an immediate postoperative radiograph as a baseline. 相似文献
9.
Polyarteritis nodosa (PAN) presents mostly as a systemic disease with poor prognosis, rarely in an isolated form with a usually favorable outcome. Both forms may affect the male reproductive system and both forms have been associated with malignancies. We describe for the first time the occurrence of isolated PAN in the reproductive system combined with a mixed germ cell tumor of the testis in a 21-year-old man presenting with symptoms of chronic epididymitis. Two years after surgery he is without evidence of recurrence of either the tumor or PAN. 相似文献
10.
Ethanol-Induced Enhancement of Cocaine Bioactivation and Irreversible Protein Binding: Evidence Against a Role of Cytochrome P-450IIE1 总被引:1,自引:0,他引:1
Urs A. Boelsterli Suzana Atanasoski Christian Göldlin 《Alcoholism, clinical and experimental research》1991,15(5):779-784
Chronic ethanol consumption potentiates cocaine-induced liver injury in rodents. Since cocaine has to be bioactivated by a cytochrome P-450-dependent N-oxidative pathway to exert its hepatotoxic effects, we studied the role of the ethanol-inducible P-450IIE1 for cocaine metabolism. Male Sprague-Dawley rats were pretreated with either a liquid diet containing ethanol (30% of calories) for 4 weeks or injected with pyrazole (200 mg/kg/day, ip, for 3 days). Both agents induced microsomal p-nitrophenol hydroxylation which is a probe for the catalytic activity of P-450IIE1. However, only ethanol, but not pyrazole, increased both microsomal cocaine N-demethylase activity (by 47%) and the extent of irreversible binding of [3H]-cocaine to microsomal proteins (by 100%), which was taken as a quantitative endpoint for the formation of a reactive metabolite. Cocaine N-demethylation and irreversible protein binding of cocaine were not inhibited by P-450IIE1 isozyme-selective substrates, nor was the rate of cocaine metabolism and binding decreased by functionally active polyclonal anti-rat P-450IIE1 antibodies. Furthermore, pyrazole pretreatment sensitized cultured hepatocytes to the glutathione-dependent cytotoxic effects of nontoxic concentrations of cocaine. These results indicate that (a) cocaine is not a major substrate for the ethanol-inducible P-450IIE1, (b) the enhancing effects of ethanol on cocaine bioactivation may be due to induction of other P-450 isoforms, and (c) induction of P-450IIE1 may potentiate cocaine-induced hepatocellular toxicity in vitro independently of cocaine metabolism, e.g., by P-450IIE1-dependent oxidative stress. 相似文献