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   242篇
  免费   9篇
  国内免费   6篇
儿科学   12篇
妇产科学   6篇
基础医学   16篇
口腔科学   1篇
临床医学   31篇
内科学   96篇
皮肤病学   3篇
神经病学   10篇
特种医学   20篇
外科学   24篇
综合类   13篇
预防医学   15篇
眼科学   2篇
药学   5篇
中国医学   1篇
肿瘤学   2篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2019年   2篇
  2018年   5篇
  2017年   2篇
  2016年   3篇
  2015年   5篇
  2014年   8篇
  2013年   2篇
  2012年   12篇
  2011年   6篇
  2010年   9篇
  2009年   14篇
  2008年   14篇
  2007年   28篇
  2006年   34篇
  2005年   14篇
  2004年   20篇
  2003年   11篇
  2002年   4篇
  2001年   2篇
  2000年   2篇
  1998年   3篇
  1997年   8篇
  1996年   5篇
  1995年   3篇
  1994年   8篇
  1993年   5篇
  1992年   2篇
  1991年   4篇
  1990年   1篇
  1989年   1篇
  1988年   4篇
  1987年   3篇
  1986年   1篇
  1982年   1篇
  1981年   2篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1968年   1篇
排序方式: 共有257条查询结果,搜索用时 15 毫秒
1.
2.
3.
Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
4.
5.
恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
6.
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle.  相似文献   
7.
8.
OBJECTIVE: Thoracic impedance cardiography (TIC) is a noninvasive method which has proved to be useful in monitoring the haemodynamic status of the patients. In this study, we evaluated the TIC findings in patients with pericardial effusion and cardiac tamponade. METHODS AND RESULTS: The study consisted of patients with pericardial effusion with (group A) or without (group B) cardiac tamponade (CT). The stroke volume, cardiac output and ejection fraction was measured by both echocardiography and TIC. The measurements were done at baseline in both groups and following pericardiocentesis in group A. The variables were compared by linear regression analysis, paired sample's t test and chi-square test. The study included 32 patients. Group A consisted of 16 patients and group B of 14 patients. Two patients were excluded from comparisons because of insufficient quality of the echocardiographic examination. There were no significant differences between group A and B with regard to demographic features. Both echocardiographic and TIC measurements at baseline revealed decreased cardiac output, EDV and SV in group A and EF was not different. Linear regression analysis revealed that echocardiography and TIC were in significant correlation with regard to cardiac output, enddiastolic volume, stroke volume (p < 0.01) but not ejection fraction (p = 0.8910). The correlation was also present after pericardiocentesis. CONCLUSIONS: TIC can be safely used in patients with pericardial effusion. It provides suggestive data for the diagnosis of CT and can be used as a means of monitoring the results of the pericardiocentesis.  相似文献   
9.
Dommisch  H.  Stolte  KN.  Jager  J.  Vogel  K.  Müller  R.  Hedtrich  S.  Unbehauen  M.  Haag  R.  Danker  K. 《Clinical oral investigations》2021,25(10):5795-5805
Objectives

Topical drug administration is commonly applied to control oral inflammation. However, it requires sufficient drug adherence and a high degree of bioavailability. Here, we tested the hypothesis whether an ester-based core-multishell (CMS) nanocarrier is a suitable nontoxic drug-delivery system that penetrates efficiently to oral mucosal tissues, and thereby, increase the bioavailability of topically applied drugs.

Material and methods

To evaluate adhesion and penetration, the fluorescence-labeled CMS 10-E-15-350 nanocarrier was applied to ex vivo porcine masticatory and lining mucosa in a Franz cell diffusion assay and to an in vitro 3D model. In gingival epithelial cells, potential cytotoxicity and proliferative effects of the nanocarrier were determined by MTT and sulphorhodamine B assays, respectively. Transepithelial electrical resistance (TEER) was measured in presence and absence of CMS 10-E-15-350 using an Endohm-12 chamber and a volt-ohm-meter. Cellular nanocarrier uptake was analyzed by laser scanning microscopy. Inflammatory responses were determined by monitoring pro-inflammatory cytokines using real-time PCR and ELISA.

Results

CMS nanocarrier adhered to mucosal tissues within 5 min in an in vitro model and in ex vivo porcine tissues. The CMS nanocarrier exhibited no cytotoxic effects and induced no inflammatory responses. Furthermore, the physical barrier expressed by the TEER remained unaffected by the nanocarrier.

Conclusions

CMS 10-E-15-350 adhered to the oral mucosa and adhesion increased over time which is a prerequisite for an efficient drug release. Since TEER is unaffected, CMS nanocarrier may enter the oral mucosa transcellularly.

Clinical relevance

Nanocarrier technology is a novel and innovative approach for efficient topical drug delivery at the oral mucosa.

  相似文献   
10.
Hepatic fibrogenesis requires sympathetic neurotransmitters   总被引:30,自引:0,他引:30  
BACKGROUND AND AIMS: Hepatic stellate cells (HSC) are activated by liver injury to become proliferative fibrogenic myofibroblasts. This process may be regulated by the sympathetic nervous system (SNS) but the mechanisms involved are unclear. METHODS: We studied cultured HSC and intact mice with liver injury to test the hypothesis that HSC respond to and produce SNS neurotransmitters to promote fibrogenesis. RESULTS: HSC expressed adrenoceptors, catecholamine biosynthetic enzymes, released norepinephrine (NE), and were growth inhibited by alpha- and beta-adrenoceptor antagonists. HSC from dopamine beta-hydroxylase deficient (Dbh(-/-)) mice, which cannot make NE, grew poorly in culture and were rescued by NE. Inhibitor studies demonstrated that this effect was mediated via G protein coupled adrenoceptors, mitogen activated kinases, and phosphatidylinositol 3-kinase. Injury related fibrogenic responses were inhibited in Dbh(-/-) mice, as evidenced by reduced hepatic accumulation of alpha-smooth muscle actin(+ve) HSC and decreased induction of transforming growth factor beta1 (TGF-beta1) and collagen. Treatment with isoprenaline rescued HSC activation. HSC were also reduced in leptin deficient ob/ob mice which have reduced NE levels and are resistant to hepatic fibrosis. Treating ob/ob mice with NE induced HSC proliferation, upregulated hepatic TGF-beta1 and collagen, and increased liver fibrosis. CONCLUSIONS: HSC are hepatic neuroglia that produce and respond to SNS neurotransmitters to promote hepatic fibrosis.  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