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   1796篇
  免费   357篇
  国内免费   16篇
耳鼻咽喉   25篇
儿科学   45篇
妇产科学   8篇
基础医学   536篇
口腔科学   49篇
临床医学   67篇
内科学   205篇
皮肤病学   51篇
神经病学   211篇
特种医学   19篇
外科学   163篇
综合类   77篇
预防医学   21篇
眼科学   11篇
药学   255篇
中国医学   135篇
肿瘤学   291篇
  2024年   2篇
  2023年   18篇
  2022年   15篇
  2021年   25篇
  2020年   55篇
  2019年   104篇
  2018年   88篇
  2017年   90篇
  2016年   96篇
  2015年   118篇
  2014年   147篇
  2013年   142篇
  2012年   127篇
  2011年   160篇
  2010年   135篇
  2009年   135篇
  2008年   117篇
  2007年   90篇
  2006年   96篇
  2005年   94篇
  2004年   76篇
  2003年   63篇
  2002年   50篇
  2001年   36篇
  2000年   20篇
  1999年   15篇
  1998年   8篇
  1997年   6篇
  1996年   1篇
  1995年   5篇
  1994年   5篇
  1993年   5篇
  1992年   4篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1985年   3篇
  1984年   4篇
  1983年   4篇
  1980年   3篇
  1978年   1篇
  1976年   1篇
  1975年   1篇
排序方式: 共有2169条查询结果,搜索用时 15 毫秒
1.
PurposeTo evaluate the midterm outcomes of percutaneous transluminal renal angioplasty (PTRA) for pediatric renovascular hypertension (RVH).Materials and MethodsThe clinical data of patients who underwent PTRA for RVH in the authors’ hospital from 2012 to 2019 were retrospectively analyzed. Postprocedural blood pressure, glomerular filtration rate (GFR) of the affected kidney, restenosis, and complications were closely monitored.ResultsPTRA was performed in a total of 30 children (20 boys and 10 girls), with a mean age of 7.3 years ± 0.7 (range, 40 days to 13.9 years) and a mean weight of 25.0 kg ± 2.3 (range, 3.4–53 kg). The median follow-up period was 26.5 months (range, 1 month to 7.5 years). Technical success was achieved in 26 (86.7%) of the 30 patients. Restenosis developed in 3 patients (10.0%). Only 1 patient underwent stent implantation, and the stent fractured 8 months later, requiring further intervention. There were no other complications. In terms of clinical benefit of blood pressure control after the initial PTRA procedure, 15 patients (50%) were cured and 7 patients (23.3%) showed improvement. There was no significant difference in the etiology, lesion location, and lesion length between patients with clinical benefit and failure (P = .06, P = .202, and P = .06, respectively). GFR of the affected kidney was significantly improved from 19.9 mL/min ± 11.2 to 38.1 mL/min ± 11.9 at the 6-month follow-up after PTRA (P < .001).ConclusionsThe overall results of PTRA for pediatric RVH caused by different etiologies are promising. PTRA not only provided a clinical benefit of blood pressure control in 73.3% of the patients but also significantly improved the function of the affected kidney.  相似文献   
2.
Many cellular signaling pathways are involved in the development of cancer. Depending on the tumor entity, the nature as well as the mode of activation can differ. Some signaling pathways frequently show changes as all tumor cells have to fulfill some basic requirements such as independence from growth factors or insensitivity against apoptosis. In this review, the possibilities of a tumor to manipulate signaling pathways to reach these goals are exemplified based on an archetypical melanoma cell. In addition, new therapeutic options based on the knowledge of signaling pathways will be discussed.  相似文献   
3.
4.
5.
核转录因子κB(nuclearfactorofkappaB ,NF κB)是一种多极性核转录因子 ,参与调控多种与免疫反应、凋亡、炎症、肿瘤形成和转移有关的基因表达。近年来 ,NF κB在肿瘤发生、耐药、转移中的作用及其机制逐渐成为医学研究的热点。本文主要综述了NF κB的结构、生物学功能及其抗凋亡诱发肿瘤的机制 ,NF κB调控的前列腺癌相关基因的表达和调控 ,NF κB参与前列腺癌浸润与转移的机制及其在前列腺癌基因治疗中的可能策略等。  相似文献   
6.
7.
8.
Resveratrol, a natural polyphenolic phytoalexin, has been considered as a potential anti-inflammatory agent because of its suppressive effect on nuclear factor-kappaB (NF-kappaB). However, we recently found that treatment of glomerular mesangial cells with resveratrol significantly and dose-dependently enhanced NF-kappaB activation triggered by proinflammatory cytokines. This finding was evidenced by different reporter assays as well as by expression of an endogenous NF-kappaB-dependent gene, intercellular adhesion molecule-1. The NF-kappaB promoting effect of resveratrol was also observed in renal tubular LLCPK1 cells, but not in HepG2 hepatoma cells. In all cell types tested, treatment with resveratrol alone did not affect NF-kappaB activity. The enhanced activation of NF-kappaB by resveratrol progressed for at least 24 h and was accompanied by sustained down-regulation of an endogenous NF-kappaB inhibitor, IkappaBbeta, but not IkappaBalpha. Although expression of inducible nitric oxide synthase was suppressed by resveratrol, nitric oxide, a negative regulator of NF-kappaB, was not involved in the regulation of NF-kappaB by resveratrol. These data elucidated, for the first time, that resveratrol may enhance activation of NF-kappaB under certain circumstances.  相似文献   
9.
Variable constitutional mosaicism, mos45,XY,-22/46,XY,-22,+mar/46,XY,-22,+r(22)/47,XY,-22,+r(22)+mar/ 47, XY,-22,+r(22)*2, was found in PHA-stimulated peripheral blood, in a lymphoblastoid cell line and in cultured skin fibroblasts from a mentally retarded patient with neurofibromatosis. Both the ring chromosome and the small extra marker chromosome stained positively by in situ hybridization with a chromosome 14/22-specific alphoid repeat probe. DNA dosage analysis showed constitutional loss of one copy of the arylsulfatase A gene (ARSA), consistent with its terminal location on 22q. There was no evidence of constitutional loss of D22S1 or D22S28 which flank the neurofibromatosis type 2 (NF2) locus. Analysis of two DNA samples from a skin neurofibroma indicated retainment of two copies of D22S1, whereas the results were ambiguous with respect to tumor-specific loss of one copy of D22S28. It is suggested that the development of neurofibromatosis of unclear type in two r(22) carriers might be associated with somatic mutation of the NF2 locus due to instability of the ring chromosome(s), and in analogy, that somatic mutation of either NF1 or NF2 may account for some cases of neurofibromatosis which do not meet the criteria of either NF1 or NF2. The occurrence of seminoma in the proband may be fortuitous, but could also be due to the presence of a seminoma-associated locus on chromosome 22.  相似文献   
10.
Tumor growths, migraine headaches, and other health‐related complications reported in patients with neurofibromatosis type 1 (NF1) are often associated with pain. Thus, this study sought to describe and quantify the pain experience in children and young adults with NF1. Surveys were administered to 49 participants (28 children and 21 adults), ages 8 through 40 years. The survey included the Numeric Rating Scale 11 (NRS11) to assess pain intensity and the Patient Reported Outcomes Measurement Information System (PROMIS) to assess pain interference. A supplemental survey was created to measure pain frequency, chronicity, quality, and location. Results suggest pain is not only present in 55% of the cohort, but that it can begin at early ages. Pain was chronic in 35% of participants, with 41% reporting the use of medication to manage pain symptoms. Common sources of pain included migraine headaches and NF‐related tumors. Pain was described as having neuropathic features (i.e., burning, tingling, numbness, or itching), and was localized to the head, back, and extremities. Further, subsets of participants reported moderate‐to‐severe pain intensity, high frequency of pain, and interference of pain in daily activities. Continued investigation of the pain experience in a multisystem disorder, such as NF1, remains essential to providing guidance in the setting of complex pain management.  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