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91.
A major histocompatibility complex class I-dependent subset of memory phenotype CD8+ cells 下载免费PDF全文
Most memory phenotype (MP) CD44(hi) CD8(+) cells are resting interleukin (IL)-15-dependent cells characterized by high expression of the IL-2/IL-15 receptor beta (CD122). However, some MP CD8(+) cells have a CD122(lo) phenotype and are IL-15 independent. Here, evidence is presented that the CD122(lo) subset of MP CD8(+) cells is controlled largely by major histocompatibility complex (MHC) class I molecules. Many of these cells display surface markers typical of recently activated T cells (CD62L(lo), CD69(hi), CD43(hi), and CD127(lo)) and show a high rate of background proliferation. Cells with this phenotype are highly enriched in common gamma chain-deficient mice and absent from MHC-I(-/-) mice. Unlike CD122(hi) CD8(+) cells, CD122(lo) MP CD8(+) cells survive poorly after transfer to MHC-I(-/-) hosts and cease to proliferate. Although distinctly different from typical antigen-specific memory cells, CD122(lo) MP CD8(+) cells closely resemble the antigen-dependent memory CD8(+) cells found in chronic viral infections. 相似文献
92.
Risk of vasovagal syncope and cardiac arrhythmias in children with mitral valve prolapse 总被引:1,自引:0,他引:1
OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients. 相似文献
93.
Functional cerebral asymmetries during the menstrual cycle: a cross-sectional and longitudinal analysis 总被引:1,自引:0,他引:1
This study aims at answering two basic questions regarding the mechanisms with which hormones modulate functional cerebral asymmetries. Which steroids or gonadotropins fluctuating during the menstrual cycle affect perceptual asymmetries? Can these effects be demonstrated in a cross-sectional (follicular and midluteal cycle phases analyzed) and a longitudinal design, in which the continuous hormone and asymmetry fluctuations were measured over a time course of 6 weeks? To answer these questions, 12 spontaneously cycling right-handed women participated in an experiment in which their levels of progesterone, estradiol, testosterone, LH, and FSH were assessed every 3 days by blood-sample based radioimmunoassays (RIAs). At the same points in time their asymmetries were analyzed with visual half-field (VHF) techniques using a lexical decision, a figure recognition, and a face discrimination task. Both cross-sectional and longitudinal analyzes showed that an increase of progesterone is related to a reduction in asymmetries in a figure recognition task by increasing the performance of the left-hemisphere which is less specialized for this task. Cross-sectionally, estradiol was shown to have significant relationships to the accuracy and the response speed of both hemispheres. However, since these effects were in the same direction, asymmetry was not affected. This was not the case in the longitudinal design, where estradiol affected the asymmetry in the lexical decision and the figural comparison task. Overall, these data show that hormonal fluctuations within the menstrual cycle have important impacts on functional cerebral asymmetries. The effect of progesterone was highly reliable and could be shown in both analysis schemes. By contrast, estradiol mainly, but not exclusively, affected both hemispheres in the same direction. 相似文献
94.
Bilateral multiple pulmonary arteriovenous malformations: endovascular treatment with the Amplatzer Vascular Plug 总被引:7,自引:0,他引:7
Cil B Canyigit M Ozkan OS Pamuk GA Dogan R 《Journal of vascular and interventional radiology : JVIR》2006,17(1):141-145
Pulmonary arteriovenous malformation (AVM) is a rare vascular malformation of the lung that carries a considerable risk of serious complications such as cerebral embolism, brain abscess, and pulmonary hemorrhage. Embolization with coils or detachable balloons is currently the preferred treatment. Paradoxical embolization of coils and balloons may occur, especially in patients with large feeding arteries. This report describes an initial experience with the use of the Amplatzer Vascular Plug used for endovascular treatment of bilateral multiple pulmonary AVMs in an adult patient. 相似文献
95.
Mevlüt Koç MD Onur Kaypakli MD Gökhan Gözübüyük MD Durmus Yıldıray Şahin MD 《Annals of noninvasive electrocardiology》2018,23(1)
Aim
Optimization of coronary sinus (CS) lead position to the latest activated left ventricular (LV) area is important to increase cardiac resynchronization therapy (CRT) response. We aimed to detect the relationship between coronary sinus lead delay index (CSDI) and echocardiographic, electrocardiographic response to CRT treatment.Methods
We prospectively included 137 consecutive patients with heart failure (HF) diagnosis, QRS ≥ 120 ms, left bundle branch block (LBBB), New York Heart Association score (NYHA) II–IV, LV ejection fraction (LVEF) <35% and scheduled for CRT (84 male, 53 female; mean age 65.1 ± 10.1 years). Echocardiographic CRT response was defined as ≥15% reduction in LV end‐systolic volume (LVESV). CS lead sensing delay was calculated as the time interval from the onset of surface QRS wave to the onset of depolarization wave recorded from the CS lead by using the CS pacing lead as a bipolar electrode. CSDI was calculated by dividing the CS lead sensing delay by the QRS duration.Results
LVESV reduction was associated with baseline QRS width (r = .257, p = .002), QRS narrowing (r = .396, p < .001), CSDI (r = .357, p < .001), and NT‐proBNP (r = ?0.213, p = .022) in bivariate analysis. In logistic regression analysis, CSDI was found to be only independent parameter for predicting significant LVESV reduction (Beta = 0.318, p < .001). CSDI was also found to be significantly associated with LVEF increase (r = .244, p = .004) and QRS narrowing (r = .178, p = .046).Conclusion
CSDI may be used as a marker to predict the favorable response to CRT. It may be useful to integrate CSDI to CRT implantation procedure in order to minimize nonresponders.96.
97.
Onur Tezel Umit Kaldirim Serkan Bilgic Suleyman Deniz Yusuf Emrah Eyi Selahattin Ozyurek Murat Durusu Nihal Tezel 《The American journal of emergency medicine》2014
Objectives
Dislocation of the shoulder joint is one of the most common dislocations. The reduction procedure is a painful procedure. In this study, 2 different treatment groups were compared for pain control during shoulder dislocation reduction. It was aimed to evaluate the differences between the groups in reduction, success, length of hospital stay, complications, side effects, patient-physician satisfaction, and ease of application.Methods
The study was planned to be prospective and randomized. As procedural sedation analgesia (SA), titration of ketamine 1 to 2 mg/kg was administered intravenously to group 1. Suprascapular nerve block (SNB) was applied under ultrasound guidance (USG) to group 2. Conformity to normal distribution of variables was examined with the Kolmogorov-Smirnov test. The χ2 test and Fisher test were used to evaluate differences between the groups in categorical variables and the Mann-Whitney U test, and a value of P < .05 was accepted as statistically significant.Results
The study comprised a total of 41 patients; 20 in the group 1 and 21 in the group 2. No statistically significant difference was determined between the groups in terms of age (P = .916), sex (P = .972), reduction success (P = .540), and patient-physician satisfaction (P = .198). The time spent in the emergency department (ED) by patients in the SA group was signficantly longer compared with the SNB group. No side effects were observed in the SNB group.Conclusions
Suprascapular nerve block, which can be easily applied under USG in the ED, can be evaluated as a good alternative to SA in the reduction of shoulder dislocations. 相似文献98.
Onur Yaprak Tolga Demirbas Cihan Duran Murat Dayangac Murat Akyildiz Yaman Tokat Yildiray Yuzer 《Hepatobiliary & Pancreatic Diseases International》2011,(5)
BACKGROUND: Varied vascular and biliary anatomies are common in the liver. Living donor hepatectomy requires precise recognition of the hilar anatomy. This study was undertaken to study donor vascular and biliary tract variations, surgical approaches and implications in living liver transplant patients. METHODS: Two hundred living donor liver transplantations were performed at our institution between 2004 and 2009. All donors were evaluated by volumetric computerized tomography (CT), CT angiography and magn... 相似文献
99.
Onur MA Cehreli ZC Tasman F Gumrukcuoglu A 《Journal of biomaterials science. Polymer edition》2005,16(4):411-419
Self-etching dentin adhesive systems, a new generation of dental-bonding agents, were investigated for their ability to block nerve conductance in the rat sciatic nerve model. Clearfil SE Bond, Mac Bond and FL Bond were used as test materials. Isolated rat sciatic nerves obtained from female albino rats were placed between two electrodes in a bath containing Tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials were recorded versus time before and after contact with the materials. Statistical analysis was performed using the Friedman and Wilcoxon Signed-Ranks tests (P = 0.01) to compare the mean percentage of inhibition between test materials versus time. All test materials were able to block nerve transmission rapidly (3.3 +/- 0.5, 5.1 +/- 2.3 and 8.0 +/- 1.9 min for SE Bond, Mac Bond and FL Bond, respectively). Significant differences were found between FL Bond and SE and Mac Bond (P < 0.01). These results indicated that the bonded systems tested, intended primarily as dentinal tubule occluders, may also exert some direct desensitizing effect on intratubular or pulpal nerve terminals in extremely deep cavities or pulpal microexposures, contributing to decreased postoperative pain. 相似文献
100.
Molecular epidemiology of macrolide-resistant Streptococcus pneumoniae isolates in Europe 总被引:3,自引:0,他引:3
Reinert RR Ringelstein A van der Linden M Cil MY Al-Lahham A Schmitz FJ 《Journal of clinical microbiology》2005,43(3):1294-1300
In many European countries, the level of pneumococcal resistance to macrolides has now passed the level of resistance to penicillin G. A total of 82 erythromycin A-resistant isolates of Streptococcus pneumoniae were collected by 11 laboratories in seven European countries. All of the isolates were tested for antimicrobial susceptibility, analyzed for clonal relatedness by multilocus sequence typing, and characterized for macrolide resistance genotypes. The prevalence of the macrolide resistance genotypes varied substantially between countries. In France (87.5% of all strains), Spain (77.3%), Switzerland (80%), and Poland (100%), strains were predominantly erm(B) positive, whereas higher levels of mef(A)-positive strains were reported from Greece (100%) and Germany (33.3%). Macrolide resistance was caused by the oligoclonal spread of some multilocus sequence types, but significant differences in clonal distribution were noted between France and Spain, countries from which high levels of macrolide resistance have been reported. Overall, sequence type 81 (Spain23F-1 clone) was by far the most widespread. The mainly erm(B)-positive serotype 14 clone (sequence type 143), first reported in Poland in the mid-1990s, is now widespread in France. 相似文献