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1.
Sympathetic skin responses from postauricular region in Meniere's disease.   总被引:10,自引:0,他引:10  
OBJECTIVE: To investigate the sympathetic nervous system activity in Meniere's disease (MD) by recording sympathetic skin responses (SSRs) from the postauricular region (PA). METHODS: Twenty-one patients with definite unilateral MD diagnosis and 12 healthy volunteers were studied by evoking right and left PA-SSRs with electrical stimulation of the left median nerve at the wrist in attack and interval periods of MD. Mean latencies and maximum amplitudes were used in statistical analyses. RESULTS: In unilateral definite MD patients, the mean latencies were longer and the maximum amplitudes were smaller on the involved ear side than those on the normal ear side (p<0.01 for both amplitude and latency) and than those from the controls (p<0.01 and p<0.05). In three patients, there was no detectable PA-SSR on the involved ear side while there were SSRs on the healthy side. In four patients, the responses were absent bilaterally during the attack period. CONCLUSIONS: There is a marked asymmetric sympathetic hypofunction in the area of the PA region of the involved ear in MD patients. SIGNIFICANCE: The PA region is a new site for recording sympathetic skin responses. PA-SSR is a useful tool to investigate sympathetic nervous system function in MD patients.  相似文献   
2.
CD59 is a 18-20-kDa membrane glycoprotein that inhibits formation of the membrane attack complex of complement (C) on homologous cells. In the present study we analyzed the expression and function of CD59 on human endothelial cells. Immunohistochemical analysis of renal cortex demonstrated a predominant expression of CD59 on peritubular capillary endothelial cells and glomerular endothelial cells. Flow cytometry analysis showed that human umbilical vein endothelial cells (HUVEC) expressed CD59 and the fluorescence intensity was approximately four times that of peripheral blood lymphocytes. CD59 is detected on sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a single 20-kDa molecule in 2% deoxycholate extracts of HUVEC. CD59 was released from the surface of HUVEC by phosphatidylinositol-specific phospholipase C, demonstrating that it is attached to the cell membrane by means of a glycolipid anchor. The functional activity of CD59 expressed on HUVEC was studied. Blocking of CD59 antigen with F(ab')2 fragments of polyclonal anti-CD59 enhanced markedly the susceptibility of HUVEC to C-mediated lysis. This effect was dependent on the amount of blocking antibodies added. Northern blot analysis revealed the presence of three species of mRNA expressed in HUVEC, which hybridized to a cDNA probe specific for CD59, with sizes of about 800, 1400 and 2000 bp. These findings suggest that CD59 may be important in protection of endothelial cells against C-mediated damage at local sites of inflammation, thereby maintaining the vascular integrity in vivo.  相似文献   
3.
Kloek  J.  Van Ark  I.  De Clerck  F.  Bloksma  N.  Nijkamp  F. P.  Folkerts  G. 《Inflammation research》2003,52(3):126-131
OBJECTIVE AND DESIGN: Since oxidative stress contributes to the pathogenesis of asthma, this study addressed the question whether supplementing the endogenous antioxidant, glutathione (GSH), would alleviate features of allergic asthma in the mouse. MATERIAL AND METHODS: Ovalbumin-sensitized mice received aerosols of the GSH-donors, glutathione-ethyl ester (GSEt) or N-acetylcysteine, before or during respiratory allergen challenges, or during methacholine challenges given one day after the last allergen challenge. Lung GSH levels were measured shortly after allergen or methacholine challenge. In addition, the effect of GSH supplements on airway hyperresponsiveness and inflammatory cell numbers in the airway lumen was assessed. RESULTS: GSEt decreased allergen-induced airway hyperresponsiveness when given in combination with methacholine. However, when given before or during allergen challenge, both GSH-donors failed to decrease the methacholine-induced airway contractility, change cell numbers in the airway lumen, or increase lung GSH levels. In addition, allergen challenges of sensitized mice did not decrease lung GSH levels. CONCLUSION: In contrast to guinea pigs and humans, allergen challenges in mice does not lead to acute oxidative stress.  相似文献   
4.
5.
Visuospatial functions are typically lateralized to the right cerebral hemisphere, giving rise to a left visual field advantage in visual half-field tasks. In a first study we investigated whether this is also true for symmetry detection off fixation. Twenty right-handed participants with left hemisphere speech dominance took part in a visual half-field experiment requiring them to judge the symmetry of 2-dimensional figures made by joining rectangles in symmetrical or asymmetrical ways. As expected, a significant left visual field advantage was observed for the symmetrical figures. In a second study, we replicated the study with 37 left-handed participants and left hemisphere speech dominance. We again found a left visual field advantage. Finally, in a third study, we included 17 participants with known right hemisphere dominance for speech (speech dominance had been identified with fMRI in an earlier study; Van der Haegen, Cai, Seurinck, & Brysbaert, 2011). Around half of these individuals showed a reversed pattern, i.e. a right visual half-field advantage for symmetric figures while the other half replicated the left visual-field advantage. These findings suggest that symmetry detection is indeed a cognitive function lateralized to the right hemisphere for the majority of the population. The data of the participants with atypical speech dominance are more in line with the idea that language and visuospatial functions are lateralized in opposite brain hemispheres than with the idea that different functions lateralize independently, although there seems to be more variability in this group.  相似文献   
6.

Purpose

The Satisfaction With Life Scale adapted for Children (SWLS-C) is a self-report measure of children’s quality of life and has exhibited sound psychometric properties. In light of increasing ethno-cultural diversity, it is important to understand child life satisfaction across diverse subgroups. Employing children’s language background as a proxy for cultural background among children in British Columbia, Canada, we examined (a) the cross-cultural measurement equivalence of the SWLS-C; and (b) cross-cultural relations of peer support and adult support with SWLS-C.

Methods

Participants were 20,119 children (Mage 9.2; 50.2% boys) who provided data as part of a self-report child health survey (the Middle-years Development Instrument). Measurement equivalence across eight language/cultural background groups was tested via multi-group confirmatory factor analysis. Multi-level analyses were used to compare: a) SWLS-C means; and b) associations of peer support and adult support with SWLS-C scores, by language/cultural background.

Results

Findings supported strict measurement equivalence between the English language/cultural background group and all other language/cultural background groups for the SWLS-C. Relative to the English language background group, SWLS-C means differed for several language/cultural background groups. Within every language/cultural background group, however, peer and adult support scale scores were significant positive correlates of SWLS-C scores.

Conclusions

This study provided evidence for measurement equivalence of a life satisfaction measure across children from diverse language/cultural backgrounds and identified between-group differences in the level of child life satisfaction that were generally consistent with prior theory and findings. Moreover, results provided evidence of promotive associations of adult support and peer support with life satisfaction among diverse groups of children.
  相似文献   
7.
The study was undertaken to search whether pedicle selection for ischemic preconditioning (IP) and duration of global ischemia applied after IP influenced efficacy of IP on flap viability in epigastric adipocutaneous island flap with bilateral pedicles in rat model. In total, 159 rats were divided into one control and three (primary, secondary, or bilateral pedicle) IP treatment groups. IP was performed on different pedicles by three cycles of 10 minutes of pedicle clamping and 10 minutes of release. After IP procedure secondary pedicle was ligated in all groups, and flaps were exposed to 0, 1, 2, 4, or 6 hours of global ischemia by clamping primary pedicle. In control groups, after the perfusion of bipedicled flaps for 1 hour, left pedicle was ligated and flaps were exposed to global ischemia as in IP groups. On day 5 post‐surgery, tissue samples and topographic measurements were taken. No significant differences in semi‐quantitative scorings of polymorphonuclear leukocytes infiltration, chronic inflammation, interstitial edema, neovascularization, VEGF, and CD105 expression levels among groups were found (P > 0.05). Percentages of necrosis were consistently smaller in IP groups compared to controls for the same duration of global ischemia, with exception of the no‐ischemia. Area of necrosis was significantly smaller in primary IP group versus secondary IP group in the absence of global ischemia (P < 0.01). In the presence of global ischemia, both primary and secondary pedicle IP groups had significantly smaller percentage of necrosis than controls (P < 0.05) and there was no significant difference between primary and secondary IP groups (P > 0.05). Thus, IP performed on different pedicles may ameliorate flap survival in a comparable fashion, depending on the duration of global ischemia. Secondary pedicle IP was as effective as primary pedicle IP and may be feasible in free flap transfers. © 2013 Wiley Periodicals, Inc. Microsurgery 34:129–135, 2014.  相似文献   
8.
Despite high vaccination coverage rates, pertussis continues to be a global concern, with increased incidence widely noted. The current pertussis epidemiologic situation has been mainly attributed to waning immunity and pathogen adaptation. To improve the disease control, a new generation of vaccines capable to overcome those weaknesses associated to the current vaccines need to be developed. Previously we have demonstrated that the outer membrane vesicles obtained from the recombinant Bordetella pertussis strain expressing PagL enzyme (OMVsBpPagL) are good vaccine candidates to protect against pertussis. In this work the OMVsBpPagL formulated with diphtheria and tetanus toxoids (TdapOMVsBpPagL) was used to evaluate its capacity to offer protection against Argentinean clinical isolates and to induce long-term immunity. To these aims BALB/c mice were immunized with TdapOMVsBpPagL and challenged with sublethal doses of the clinical isolate Bp106 selected as a representative circulating isolate. Comparisons with a current commercial Tdap vaccine used at a dose in which pertussis toxin level was equivalent to that of TdapOMVsBpPagL were performed. With the normalized doses of both vaccines we observed that TdapOMVsBpPagL protected against the clinical isolate infection, whereas current commercial Tdap vaccine showed little protection against such pathogen. Regarding long-term immunity we observed that the TdapOMVsBpPagL protective capacity against the recommended WHO reference strain persisted at least 9 months. In agreement with these results TdapOMVsBpPagL induced Th1 and Th2 immune response. In contrast, commercial Tdap induced Th2 but weak Th1 responses. All results presented here showed that TdapOMVsBpPagL is an interesting formulation to be considered for the development of novel acellular multi-antigen vaccine.  相似文献   
9.
BACKGROUND: Reduced salivary flow has been reported in patients undergoing hemodialysis (HD) treatment. Our aim was to investigate the most important factors associated with stimulated salivary flow rate (ssfr) in chronic HD patients. METHODS: Fifty HD patients (27 F, 23 M, mean age 46. 7 +/- 13.2 years) were divided into two groups according to the duration of HD treatment as those receiving HD therapy less than or equal to (group I) or those more than (group II) 24 months. Fasting blood samples were obtained to determine hepatitis B and C serology, and biochemical and hematological parameters before a HD session. After prestimulation with a standard weight paraffin wax, stimulated saliva was collected in the HD patients and control group (23 F, 25 M, mean age 45.7 +/- 19.1 years) and the flow rate was expressed as ml/min. RESULTS: Both HD groups consisted of 25 patients. There was no significant difference between the two HD groups other than serum alkaline phosphatase (ALP) levels and presence of HCV. The ssfr was decreased than controls in both groups (0.8 +/- 0.6 and 0.7 +/- 0.4, respectively, vs. 1.5 +/- 0.5 ml/min) and it did not correlate with any parameter. Smoking had a positive effect on ssfr in all groups. CONCLUSION: Although the salivary flow rate decreased significantly in chronic HD patients, the duration of therapy displayed no effect on the salivary changes in HD patients, but smoking increased ssfr.  相似文献   
10.
INTRODUCTION: The structure called the residual gubernaculum (G) has been evaluated to define its origin. MATERIALS AND METHODS: Girls operated for inguinal hernia (n = 7) and boys operated for undescended testis (n = 12), inguinal hernia (n = 7), hydrocele of the cord (n = 1), and ectopic (n = 1) and entrapped (n = 1) testes were evaluated. Attachments of the structures coursing distally from the sacs were identified, and they were removed en block. Three samples, first from the distal part of the sac with the beginning of the fibrous structure, second from the midportion, and third from the most distal part, were prepared and stained with hematoxylin-eosin, trichrome and elastic van Gieson. Histologic structures within the samples were determined and compared with Mann-Whitney U test. RESULTS AND CONCLUSIONS: Structures called the residual G differed from the walls of accompanying sacs by only the absence of mesothelial lining. Therefore, the structure called the residual G in boys with an undescended testis and the round ligament in girls actually represent the obliterated processus vaginalis.  相似文献   
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