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   3316篇
  免费   186篇
  国内免费   28篇
耳鼻咽喉   20篇
儿科学   52篇
妇产科学   77篇
基础医学   390篇
口腔科学   104篇
临床医学   263篇
内科学   735篇
皮肤病学   107篇
神经病学   526篇
特种医学   107篇
外科学   550篇
综合类   8篇
预防医学   109篇
眼科学   29篇
药学   176篇
中国医学   4篇
肿瘤学   273篇
  2024年   4篇
  2023年   24篇
  2022年   77篇
  2021年   137篇
  2020年   82篇
  2019年   83篇
  2018年   120篇
  2017年   103篇
  2016年   118篇
  2015年   113篇
  2014年   174篇
  2013年   207篇
  2012年   284篇
  2011年   286篇
  2010年   174篇
  2009年   146篇
  2008年   248篇
  2007年   211篇
  2006年   182篇
  2005年   188篇
  2004年   177篇
  2003年   164篇
  2002年   113篇
  2001年   10篇
  2000年   10篇
  1999年   14篇
  1998年   10篇
  1997年   5篇
  1996年   8篇
  1995年   5篇
  1993年   4篇
  1992年   3篇
  1990年   3篇
  1989年   2篇
  1988年   2篇
  1987年   4篇
  1986年   5篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1975年   1篇
  1974年   7篇
  1973年   4篇
  1972年   4篇
  1971年   3篇
  1969年   1篇
  1968年   1篇
排序方式: 共有3530条查询结果,搜索用时 62 毫秒
81.
Gastrointestinal complications are common after renal transplantation, and they have a wide clinical spectrum, varying from diarrhoea to post-transplant inflammatory bowel disease(IBD). Chronic immunosuppression may increase the risk of post-transplant infection and medication-related injury and may also be responsible for IBD in kidney transplant re-cipients despite immunosuppression. Differentiating the various forms of post-transplant colitis is challenging, since most have similar clinical and histological features. Drug-related colitis are the most frequently encountered colitis after kidney transplantation, particularly those related to the chronic use of mycophenolate mofetil, while de novo IBDs are quite rare. This review will explore colitis after kidney transplantation, with a particular focus on different clinical and histological features, attempting to clearly identify the right treatment, thereby improving the final outcome of patients.  相似文献   
82.
The increasing demand for organ donors to supply the increasing number of patients on kidney waiting lists has led to most transplant centers developing protocols that allow safe utilization from donors with special clini cal situations which previously were regarded as contra indications.Deceased donors with previous hepatitis C infection may represent a safe resource to expand the donor pool.When allocated to serology-matched recipi ents,kidney transplantation from donors with hepatitis C may result in an excellent short-term outcome and a significant reduction of time on the waiting list.Specia care must be dedicated to the pre-transplant evaluation of potential candidates,particularly with regard to live functionality and evidence of liver histological damage such as cirrhosis,that could be a contraindication to transplantation.Pre-transplant antiviral therapy could be useful to reduce the viral load and to improve the long-term results,which may be affected by the progression of liver disease in the recipients.An accurate selection of both donor and recipient is mandatory to achieve a satisfactory long-term outcome.  相似文献   
83.
We present the case of a young woman corrected with a Mustard procedure undergoing successful transvenous double chamber pacemaker implantation with the atrial lead placed in the systemic venous channel. The case presented demonstrates that, when the systemic venous atrium is separate from the left atrial appendage, the lead can be easily and safely placed in the systemic venous left atrium gaining satisfactory sensing and pacing thresholds despite consisting partially of pericardial tissue.  相似文献   
84.
85.
86.
87.
This study aimed to investigate 1) the relationship between subjective perception of quality of life (QoL) and clinician-rated levels of psychosocial functioning and 2) the relationship of these indicators with neuropsychological performances, in a sample of 117 subjects with mood and anxiety disorders hospitalized for a 4-week psychiatric rehabilitation program. At the beginning of the hospitalization, QoL and clinician-rated functioning were respectively measured by the World Health Organization Quality of Life Assessment-Brief Form (WHOQOL-BREF) and the Global Assessment of Functioning (GAF) scale, and subjects were administered a neuropsychological battery evaluating verbal and visual memory, working memory, attention, visual-constructive ability, language fluency and comprehension. We did not find any association between WHOQOL-BREF and GAF scores and between cognitive impairment and lower QoL or clinician-rated functioning. Our results suggest that 1) the individuals' condition encompasses different dimensions that are not fully captured by using only clinician-rated or self-administered evaluations; 2) the GAF scale seems unable to indicate the cognitive impairments of our subjects and the WHOQOL-BREF does not appear to be influenced by these deficits. Overall, our findings suggest the need of simultaneously use of multiple assessment tools, including objective evaluations of functioning and different measures of QoL, in order to obtain a more complete clinical picture of the patients. This may allow to identify more specific targets of therapeutic interventions and more reliable measures of outcome.  相似文献   
88.
We have generated unique asymmetric liposomes with phosphatidylserine (PS) distributed at the outer membrane surface to resemble apoptotic bodies and phosphatidic acid (PA) at the inner layer as a strategy to enhance innate antimycobacterial activity in phagocytes while limiting the inflammatory response. Results show that these apoptotic body-like liposomes carrying PA (ABL/PA) (i) are more efficiently internalized by human macrophages than by nonprofessional phagocytes, (ii) induce cytosolic Ca(2+) influx, (iii) promote Ca(2+)-dependent maturation of phagolysosomes containing Mycobacterium tuberculosis (MTB), (iv) induce Ca(2+)-dependent reactive oxygen species (ROS) production, (v) inhibit intracellular mycobacterial growth in differentiated THP-1 cells as well as in type-1 and -2 human macrophages, and (vi) down-regulate tumor necrosis factor (TNF)-α, interleukin (IL)-12, IL-1β, IL-18, and IL-23 and up-regulate transforming growth factor (TGF)-β without altering IL-10, IL-27, and IL-6 mRNA expression. Also, ABL/PA promoted intracellular killing of M. tuberculosis in bronchoalveolar lavage cells from patients with active pulmonary tuberculosis. Furthermore, the treatment of MTB-infected mice with ABL/PA, in combination or not with isoniazid (INH), dramatically reduced lung and, to a lesser extent, liver and spleen mycobacterial loads, with a concomitant 10-fold reduction of serum TNF-α, IL-1β, and IFN-γ compared with that in untreated mice. Altogether, these results suggest that apoptotic body-like liposomes may be used as a Janus-faced immunotherapeutic platform to deliver polar secondary lipid messengers, such as PA, into phagocytes to improve and recover phagolysosome biogenesis and pathogen killing while limiting the inflammatory response.  相似文献   
89.
Background: Insufficient alveolar bone height often prevents the placement of standard dental implants in the posterior part of edentulous maxilla. In order to increase adequately the vertical dimension of the reabsorbed alveolar process, a sinus lift procedure is often necessary. The aim of this study was to evaluate histologic results of a prehydrated corticocancellous porcine bone used in maxillary sinus augmentation. Methods: Patients (age 18–70 years) with a residual bone height requiring a maxillary sinus augmentation procedure to place dental implants were eligible for this study. All patients were treated with the same surgical technique consisting of sinus floor augmentation via a lateral approach. The space obtained by elevation of the mucosa wall was grafted with prehydrated and collagenated corticocancellous porcine bone. Biopsies were harvested 6 months after the augmentation procedures. Results: Twenty‐four patients were enrolled. The mean percentage of new formed bone was 43.9 ± 18.6% (range 7.5–100%), whereas the mean percentage of residual graft material was 14.2 ± 13.6% (range 0–41.9%). The new bone/residual graft material ratio in the maxillary sinuses was 3.1. The mean soft tissues percentage was 41.8 ± 22.7% (range 0–92.5%). Conclusion: The present study suggested that porcine bone showed excellent osteoconductive properties and could be used successfully for sinus augmentation. Moreover, the porcine bone showed a high percentage of reabsorption after 6 months; this might be because of the presence of collagen and the porosity of the graft material.  相似文献   
90.
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