首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9386篇
  免费   604篇
  国内免费   17篇
耳鼻咽喉   121篇
儿科学   189篇
妇产科学   248篇
基础医学   1440篇
口腔科学   119篇
临床医学   827篇
内科学   1882篇
皮肤病学   380篇
神经病学   783篇
特种医学   445篇
外国民族医学   1篇
外科学   1382篇
综合类   48篇
一般理论   9篇
预防医学   655篇
眼科学   210篇
药学   559篇
中国医学   8篇
肿瘤学   701篇
  2023年   47篇
  2022年   106篇
  2021年   160篇
  2020年   126篇
  2019年   125篇
  2018年   171篇
  2017年   142篇
  2016年   197篇
  2015年   258篇
  2014年   302篇
  2013年   393篇
  2012年   583篇
  2011年   620篇
  2010年   343篇
  2009年   331篇
  2008年   472篇
  2007年   512篇
  2006年   524篇
  2005年   504篇
  2004年   454篇
  2003年   418篇
  2002年   390篇
  2001年   220篇
  2000年   218篇
  1999年   191篇
  1998年   119篇
  1997年   96篇
  1996年   70篇
  1995年   67篇
  1994年   67篇
  1993年   60篇
  1992年   107篇
  1991年   95篇
  1990年   124篇
  1989年   97篇
  1988年   64篇
  1987年   75篇
  1986年   68篇
  1985年   64篇
  1984年   63篇
  1983年   58篇
  1980年   43篇
  1979年   70篇
  1978年   41篇
  1977年   45篇
  1976年   41篇
  1975年   63篇
  1974年   46篇
  1973年   60篇
  1970年   43篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.

Introduction

Compression fractures of the cuboid bone in children and adolescents are rare. Fracture morphology, associated lesions, treatment options and long-term outcomes of this very rare injury are published in a few case reports. This study with review of the literature aims to support the understanding of fracture pattern and optimize pathways of decision making.

Material and Methods

A retrospective two-center study was performed in a patient cohort treated between 2001 and 2016. All patients aged less than 18 years who sustained a cuboid fracture were included. Age, gender, mechanism of injury, fracture morphology, amount of displacement, associated injuries, and therapy were analyzed. In the follow-up (FU), the AOFAS Midfoot Scale was investigated.

Results

Fractures of the cuboid bone were diagnosed in 7 boys and 9 girls. The mean age of the patients was 10 years (range: 2.2–16.1 years). According to the classification of Fenton we detected 11 (69%) type 2, 2 (12%) type 3 and 3 (19%) type 5b fractures. Other fracture types according to Fenton were not observed. All children under 10 years sustained a type 2 fracture. Open reduction and internal fixation was performed in 5 (31%) patients. Bone grafting was not necessary. FU was performed in 14/16 patients on average after 9 years (mean; range: 1.4–16.2 years). The mean AOFAS Midfoot Scale at FU for extra-articular type 2 fractures was 100 points, whereas in intra-articular fractures (Type 3) and fractures associated with mid-tarsal disruption (type 5b) worse results were found (95 and 66 points, accordingly).

Conclusion

This rare injury shows inhomogenous morphologies and offers different treatment approaches. Extra-articular Fenton type 2 lesions are the most common type of cuboid fracture in children (69%). A potential loss of length of the lateral column must be considered. In contrast to adults, type 1, 4, and 5a fractures were not found in our cohort of children and adolescents. Lower scores of the AOFAS Midfoot Scale were found with either intra-articular involvement or associated midfoot lesions.  相似文献   
3.
4.
5.
In the United States, renal cell carcinoma (RCC) incidence and the prevalence of obesity, an established risk factor for RCC, have been increasing for several decades. RCC is more common among older individuals. We sought to quantify the contribution of excess adiposity to the rising incidence of RCC among individuals 60 years or older. National Institutes of Health-American Association of Retired Persons Diet and Health Study data (n = 453 859 participants, enrolled in 1995-1996, age at enrollment 50-71 years) were used to estimate multivariable-adjusted hazard ratios (HRs) for RCC across body mass index categories and HRs associated with smoking. Population attributable fractions (PAFs) were calculated using estimated HRs and annual overweight/obesity prevalence from the National Health Interview Survey (1985-2008). PAF estimates were combined with RCC incidence from Surveillance, Epidemiology and End Results-13 to calculate annual percent changes in RCC incidence attributable (and unrelated) to overweight/obesity. We found that between 1995 and 2018, among individuals aged 60 years and older, PAF for overweight/obesity increased from 18% to 29% for all RCCs. In comparison, the PAF for smoking declined from 12% to 9%. RCC incidence increased 1.8% per year (95% confidence interval [CI] 1.5%-2.1%) overall, while RCC incidence attributable to overweight/obesity increased 3.8% per year (95%CI 3.5%-4.2%) and RCC incidence unrelated to overweight/obesity increased 1.2% per year (95% CI 0.9%-1.4%). In conclusion, overweight/obesity appears to have contributed importantly to the rising incidence of RCC in the United States since the mid-1990s. Public health interventions focused on reducing overweight and obesity could help substantially in curbing this trend.  相似文献   
6.
The regrowth of amputated digit tips represents a unique regenerative healing in mammals with subcutaneous volume regrowth, restoration of dactylogram, and suppression of scar formation. Although factor analysis in amphibians and even in mice is easy to obtain, safety of harvesting biomaterial from human digit tip amputations for analysis has not yet been described.The aim of this study was to evaluate if recovering wound exudate does hamper clinical outcome or influence microbiologic or inflammation status.A predefined cohort of 18 patients with fresh digit tip amputations was randomly assigned to receive standard therapy (debridement, occlusive dressing) with (n = 9) or without (n = 9) collection of the whole wound exudate in every dressing change. Primary endpoint (lengthening) and secondary endpoints (regeneration of dactylogram, nail bed and bone healing, time to complete wound closure, scar formation, 2-point discrimination, microbiologic analysis, inflammatory factors interleukin (IL)-1α, tumor necrosis factor-α, IL-4, and IL-6) were determined by an independent, blinded observer.Patients’ characteristics showed no significant differences between the groups. All patients completed the study to the end of 3 months follow-up. Exudate collection did not influence primary and secondary endpoints. Furthermore, positive microbiologic findings as well as pus- and necrosis-like appearance neither impaired tissue restoration nor influenced inflammatory factor release.Here, the authors developed an easy and safe protocol for harvesting wound exudate from human digit tip amputations. For the first time, it was shown that harvesting does not impair regenerative healing. Using this method, further studies can be conducted to analyze regeneration associated factors in the human digit tip.DRKS.de Identifier: DRKS00006882 (UTN: U1111-1166-5723).  相似文献   
7.
8.
9.
In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method.  相似文献   
10.
Zusammenfassung Der sekretorische Mittelohrkatarrh stellt, was zumeist zu wenig berücksichtigt wird, keine einheitliche Erkrankung dar. In der Mehrzahl der Fälle handelt es sich um eineseröse Entzündung mit Exsudat, serologische Untersuchungen sowie klinische Beobachtungen und Erwägungen sprechen eindringlich dafür, in den anderen Fällen liegt infolge eines Tubenverschlusses durch Tumordruck oder Narbenstriktur einHydrops (Transsudat) vor, wobei nicht feststeht, ob dieser ex vacuo oder durch Stauung zustande kommt. In Fülen von Tumor begünstigt vielleicht die Kachexie die Bildung des Transsudates.Nach Abschluß meiner Arbeit mußte ich feststellen, daß mir bei der Durchsicht des Schrifttums eine Arbeit vonN. Rh. Blegvad, erschienen in der Monatsschrift für Ohrenheilkunde 1932 unter dem Titel Ist der Begriff Tubenokklusion aufrecht zu erhalten ? völlig entgangen war. So sehr ich dieses Versehen bedauere, so sehr hat es mich gefreut, in dieser Arbeit vielfach den gleichen Gedankengängen begegnet zu sein, wie ich sie oben, vollkommen unabhängig davon, entwickelt habe.Herrn ProfessorZange, zum 60. Geburtstag.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号