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   1756篇
  免费   40篇
  国内免费   83篇
耳鼻咽喉   6篇
儿科学   35篇
妇产科学   23篇
基础医学   304篇
口腔科学   7篇
临床医学   101篇
内科学   386篇
皮肤病学   84篇
神经病学   72篇
特种医学   22篇
外科学   463篇
综合类   95篇
预防医学   53篇
眼科学   22篇
药学   83篇
中国医学   26篇
肿瘤学   97篇
  2023年   30篇
  2022年   68篇
  2021年   78篇
  2020年   61篇
  2019年   53篇
  2018年   66篇
  2017年   46篇
  2016年   69篇
  2015年   32篇
  2014年   80篇
  2013年   87篇
  2012年   68篇
  2011年   103篇
  2010年   68篇
  2009年   66篇
  2008年   68篇
  2007年   84篇
  2006年   68篇
  2005年   59篇
  2004年   63篇
  2003年   50篇
  2002年   40篇
  2001年   39篇
  2000年   34篇
  1999年   28篇
  1998年   28篇
  1997年   31篇
  1996年   30篇
  1995年   32篇
  1994年   42篇
  1993年   28篇
  1992年   37篇
  1991年   30篇
  1990年   18篇
  1989年   14篇
  1988年   15篇
  1987年   7篇
  1986年   7篇
  1985年   6篇
  1984年   4篇
  1983年   5篇
  1982年   6篇
  1981年   8篇
  1980年   8篇
  1979年   6篇
  1977年   2篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
  1907年   1篇
排序方式: 共有1879条查询结果,搜索用时 15 毫秒
71.
72.
《Diabetes & metabolism》2014,40(3):229-234
The aim of this study was to investigate the effectiveness of immunomodulatory peptides in preventing the spontaneous onset of Type 1 diabetes in NOD mice. Two such peptides, CP and C1, were injected intraperitoneally in NOD mice three times a week starting at two different time points, nine weeks and 11 weeks of age, and blood sugar levels monitored for the development of diabetes. CP was shown to be effective in delaying the onset of diabetes compared to control (P = 0.006). The timing of peptide administration was crucial since delay in treatment did not prevent the onset of diabetes (nine weeks versus 11 weeks of age). C1 was effective in delaying the onset of Type 1 diabetes with borderline significance when given at week 11 (P = 0.05). These findings confirm the efficacy of these peptides in the prevention and possible treatment for Type 1 diabetes and thereby create new opportunities for genetic manipulation.  相似文献   
73.
74.
BACKGROUNDCoronavirus disease (COVID) is a new and highly contagious infectious disease caused by the coronavirus (COVID-19 or severe acute respiratory syndrome coronavirus 2). There is limited data regarding the incidence and management of COVID-19 in immunocompromised patients’ post-transplantation. In the pre-COVID-19 era, these patients were already at an increased risk of developing opportunistic infections. These often manifested with atypical symptoms.CASE SUMMARYWe report another case of uneventful COVID-19 pneumonia in a 58-year old male who was 18 mo’ post liver transplantation. He received tacrolimus monotherapy since July 2019. The clinical manifestations included only epigastric pain radiating to the right hypochondrium, nausea and vomiting. He had no fevers, cough, shortness of breath, anosmia or dysgeusia even if the chest computed tomography scan revealed an extension of the multiple patchy ground-glass density shadows to the upper lobe of the left lung too. He was hospitalised and received a course of oral chloroquine (200 mg × 3 per day) for a period of 10 d. Interestingly, the COVID 19 infection was uneventful though there were no modifications to his tacrolimus dosing. He was successfully discharged. We performed subsequent follow-up via telemedicine.CONCLUSIONIn light of the current pandemic, it is even more important to identify how the liver recipient’s patients present and are managed, especially for immunosuppression treatment.  相似文献   
75.
Mesenchymal stromal cells(MSCs) are multipotent and self-renewing cells that reside essentially in the bone marrow as a non-hematopoietic cell population, but may also be isolated from the connective tissues of most organs. MSCs represent a heterogeneous population of adult, fibroblast-like cells characterized by their ability to differentiate into tissues of mesodermal lineages including adipocytes, chondrocytes and osteocytes. For several years now, MSCs have been evaluated for their in vivo and in vitro immunomodulatory and ‘tissue reconstruction’ properties, which could make them interesting in various clinical settings, and particularly in organ transplantation. This paper aims to review current knowledge on the properties of MSCs and their use in pre-clinical and clinical studies in solid organ transplantation, and particularly in the field of liver transplantation. The first available clinical data seem to show that MSCs are safe to use, at least in the medium-term, but more time is needed to evaluate the potential adverse effects of long-term use. Many issues must be resolved on the correct use of MSCs. Intensive in vitro and pre-clinical research are the keys to a better understanding of the way that MSCs act, and to eventually lead to clinical success.  相似文献   
76.
Preclinical immunotoxicity assessments may be performed during pharmaceutical drug development in order to identify potential cause for concern prior to use in the clinic. The in vivo T-dependent antibody response (TDAR) is widely used in this regard, given its sensitivity to known immunosuppressive compounds, but may be impractical early in drug development where quantities of test article are limited. The goal of the current work is to develop an in vitro human cell-based assay that is sensitive to immunosuppression, uses relatively small quantities of test article, and is simple to perform with moderate to high throughput. Ideally, this assay would require the cooperation of multiple cellular compartments to produce a response, similar to the TDAR. Although the Mishell–Dutton assay (in vitro mouse splenic sheep red blood cell response) has been used for this purpose, it shows considerable inter-laboratory variability, and rodent cells are used which leads to potential difficulty in translation of findings to humans. We have developed an assay that measures an influenza antigen-specific response using frozen-stored human peripheral blood mononuclear cells, which we have termed the human lymphocyte activation (HuLA) assay. The HuLA assay is sensitive to cyclosporine, dexamethasone, rapamycin, mycophenolic acid, and methotrexate at concentrations within their respective therapeutic ranges. Although proliferation is the primary endpoint, we demonstrate that flow cytometry approaches may be used to characterize the proliferating lymphocyte subsets. Flu antigen-specific proliferation in the HuLA assay primarily involves both CD4+ and CD8+ T-lymphocytes and B-lymphocytes, although other lymphocyte subsets also proliferate. In addition, flu-specific antibody-secreting cells can be measured in this assay by ELISPOT, a response that is also sensitive to known immunosuppressive compounds. The HuLA assay represents a relatively straightforward assay with the capability of detecting immune suppression in human cells and can be applied to compound ranking and immunotoxicity assessment.  相似文献   
77.
目的:研究头孢曲松对脓毒症模型小鼠脾脏树突状细胞(DCs)的影响,及其临床意义.方法:96只雄性昆明鼠随机分配入组,正常对照组(A组)40只、脓毒症模型组(B组)32只、头孢曲松治疗组(C组)24只.采用盲肠结扎穿孔术(CLP)制模,制模后0、12、24、48、72 h分批处死小鼠,流式细胞计数脾脏DCs及凋亡率.结果:与正常观察组比较,模型组所有观察时间点脾脏DCs数量明显减少,凋亡率增加(均P<0.05);给予头孢曲松治疗后脾脏DCs的丢失进一步加剧(P<0.05),但凋亡率无显著改变(P>0.05).结论:严重脓毒症时脾脏DCs明显减少.常规使用头孢曲松加剧DCs的丢失,但凋亡率无显著改变,推测源于单核细胞向DCs的分化障碍,从而加剧了免疫抑制和炎症失衡.  相似文献   
78.
Although rare, atrial myxoma is the most common primary tumour of the heart. Its relation to immunosuppression in solid organ transplant is presently debateable. We report the case of a 71-year-old male patient who underwent renal transplant 17 years prior. Since that time he continued high dose immunosuppression without physician consultation and presented to us with atrial myxoma and its complications raising the question of any association between immunosuppression and the development of atrial myxoma.  相似文献   
79.
IntroductionThe objetive of these study is to know the characteristics of COVID-19 in patients with uveitis associated with Systemic Autoimmune Disease (SAD) through telematic survey.Material and methodsInternal Medicine Society and Group of Systemic Autoimmune disease conducted a telematic survey of patients with SAD to learn about the characteristics of COVID-19 in this population.ResultsA total of 2,789 patients answered the survey, of which 28 had a diagnosis of uveitis associated with SAE. The majority (82%) were female and caucasian (82%), with a mean age of 48 years. The most frequent SAEs were Behçet's disease followed by sarcoidosis and systemic lupus erythematosus. 46% of the patients were receiving corticosteroid treatment at a mean prednisone dose of 11 mg/day. Regarding infection, 14 (50%) patients reported symptoms compatible with SARS-CoV-2 infection. RT-PCR was performed on the nasopharyngeal smear in two patients and in one of them (4%) it was positive.ConclusionsBoth asymptomatic and symptomatic COVID-19 patients with ASD-associated UNI had received similar immunosuppressive treatment.  相似文献   
80.

Background

Aim of the present study was to investigate whether 1,25(OH)(2)D(3) (Vitamin D3) modulates T lymphocyte functions in patients transplanted for hepatitis C virus-related cirrhosis.

Methods

Sixteen patients and ten healthy subjects were investigated. T lymphocytes were activated in vitro in the presence or absence of Vitamin D3 and then the proliferative response and IFN-γ and TNF-α production were assessed.

Results

Vitamin D3 potently reduced T-lymphocyte proliferation in a dose-related fashion. Similarly, FACS analysis and ELISA testing demonstrated that Vitamin D3 significantly decreased the response frequency and the response intensity of IFN-γ and TNF-α production in the whole CD3-positive T lymphocyte population as well as in “naive” CD4+ CD45RA+ and “memory” CD4+ CD45RO+ T lymphocyte subsets. The inhibitory effect of Vitamin D3 on T-cell proliferation and cytokine production was not different between patients and controls. No toxic effects were exerted by Vitamin D3 even at the higher concentration used (10 nM). Finally, no statistically significant correlation was found between 25(OH)D serum levels and the proliferative response or cytokine production of T lymphocytes from transplanted patients.

Conclusions

This study demonstrates that in patients transplanted for hepatitis C virus-related cirrhosis Vitamin D3 modulates T lymphocyte activation, and provides a rationale for the evaluation of this compound as an immunosuppressive agent in liver-transplanted patients.  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