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971.
972.
目的 探讨学龄前和学龄期良性阵发性眩晕(BPV)患儿临床特征差异性。 方法 选取BPV患儿48例,通过眩晕问卷调查、听力学检查、前庭功能检查,对比分析学龄前和学龄期BPV患儿在临床表现、前庭功能的特点。 结果 48例BPV患儿中男22例、女26例,年龄3~12岁,中位年龄7.0岁;学龄前患儿25例,学龄期患儿23例。学龄前及学龄期患儿临床表现为恶心、呕吐率分别为35.7%(10/28)和64.3%(18/28),平衡功能障碍率分别为85.7%(12/14)和14.3%(2/14),伴发头痛率分别为18.2%(2/11)和81.8%(9/11),学龄前和学龄期患儿恶心、呕吐率、平衡功能障碍率、伴发头痛率比较,差异有统计学意义(P均<0.05);辅助检查中纯音测听、声导抗、高刺激率ABR、前庭冷热气检查方面,学龄前和学龄期患儿比较,差异无统计学意义。 结论 学龄前和学龄期BPV患儿在临床表现、平衡障碍、伴发头痛方面有所不同。  相似文献   
973.
974.
Nematode infections are generally followed by high rates of reinfection, leading to elevated prevalence in endemic areas. Therefore, the effective control of nematode infections depends on understanding the induction and regulation of protective mechanisms. However, most experimental models for protective immune response against nematodes use high parasite exposure, not always reflecting what occurs naturally in human populations. In this study, we tested whether infecting mice with different Strongyloides venezuelensis larvae loads would affect protective responses against reinfection. Interestingly, we found that a previous infection with 10–500 larvae conferred high rate of protection against reinfection with S. venezuelensis in mice, by destroying large numbers of migrating larvae. However, low‐dose priming did not abolish adult worm maturation, as detected in high‐dose primed group. Results also indicated that a previous low‐dose infection delayed the development of cellular infiltrate, while a high inoculum rapidly induced these inflammatory features. Cytokine production by splenocyte cultures of challenge infected mice demonstrated that low‐dose priming had increased production of IL‐4 and IFN‐γ, while high‐dose induced IL‐4 production but not IFN‐γ. Our data support the hypothesis that low‐dose nematode infection does not induce a polarized type‐2 immune response, allowing adult worm survival.  相似文献   
975.
Abstract

Objective. Galactose elimination capacity (GEC) is used as a quantitative measure of liver metabolic function with prognostic value in adults with acute and chronic liver failure. Almost no data are available regarding GEC in children, however. This study thus aims to meet the previously unmet clinical need for age-related data on GEC in children. Material and methods. We studied galactose elimination in 10 healthy children (median age 10.7 years; range 7 months to 16 years) and 30 children with chronic liver disease (median age 8.6 years; range 3 months to 16 years). GEC was estimated from the linear decrease in concentration of galactose in arterialized capillary blood from the ear following intravenous infusion of galactose. Results. In both groups of children, GEC (μmol/min/kg body weight) was highest in the youngest children and decreased with age, although at a significantly lower level in the children with liver disease (p = 0.05). GEC was significantly higher in healthy children than in healthy adults, diminishing to the adult level by the age of 16 years. Conclusions. GEC was found to be higher in children than in adults until the age of 16 years. Moreover, GEC was significantly lower in children with chronic liver disease than in healthy children, underlining that GEC testing also has potential clinical usefulness as a quantitative measure of liver metabolic function in children.  相似文献   
976.
《Substance use & misuse》2013,48(10):1542-1557
This study was aimed at assessing the psychometric qualities of the fast alcohol screening test (FAST), and at comparing these qualities to those of the alcohol use disorders identification test (AUDIT) in three samples of Brazilian adults: (i) subjects attended at an emergency department (530); (ii) patients from a psychosocial care center (40); and (iii) university students (429). The structured clinical interview for diagnosis (SCID)-IV was used as gold standard. The FAST demonstrated high test–retest and interrater reliability coefficients, as well as high predictive and concurrent validity values. The results attest the validity and reliability of the Brazilian version of the FAST for the screening of indicators of alcohol abuse and dependence.  相似文献   
977.
Objective To study the human myxovirus resistant protein A (MxA), a specifically induced peptide by interferon I, and to use its level as a diagnostic criterion for viral infections. Methods Anti-MxA antisera from immunized mice were prepared with the expressed MxA protein of pET32a-MxA in E. coli BL-21(DE3). To confirm the antiserum activity and specificity, the expression product of BL21, wild type MxA pEGFP-CI-wMxA and site-directed mutant MxA pEGFP-Cl-mMxA(N589S) stably transfected 3T3 cells and induced A549 cells were detected by Western blot with the antisera using non-MxA transfected or non-IFN-[3 induced cells, intact A549, NIH 3T3 cells transfected with pEGFP-CI and pET32a (+)-transformed BL-21 as controls. Results The antisera had specific positive immunoreactivity to the NIH3T3 cells transformed with pEGFP-CI-wMxA and pEGFP-CI-mMxA, INF-β induced A549 cells and BL21 proteins expressed with pET32a (+)-MxA. The hybridization signals from IFN-β induced A549 cells depended on the IFN-β inducing concentrations. Meanwhile, immunohistochemical assay showed that NIH 3T3 cells with pEGFP-C 1-wMxA and pEGFP-C 1-mMxA had 〉 98% of positive cells at 1:50 dilution of the serum and A549 cells induced by 20 ng/mL IFN-[3 for 48 h showed 95% positive cells. pEGFP-Cl-transfected NIH 3T3 cells were all negative. Conclusion Anti-sera are highly specific to diversified MxAs. The antibody is detectable by Western blot, immunocytochemistry and immunofluorescence assay.  相似文献   
978.
Phalen's test has been one of the most significant of clinical signs when making a clinical diagnosis of idiopathic carpal tunnel syndrome (CTS). However, it is unknown whether intraneural blood flow changes during Phalen's test in patients with CTS. In this study, an intraoperative Phalen's test was conducted in patients with CTS to observe the changes in intraneural blood flow using a laser Doppler flow meter. During Phalen's test, intraneural blood flow showed a sharp decrease, which lasted for 1 min. Intraneural blood flow decreased by 56.7%–100% (average, 78.0%) in the median nerve relative to the blood flow before the test. At 1 min after completing the test, intraneural blood flow returned to the baseline value. After carpal tunnel release, there was no marked decrease in intraneural blood flow. This study demonstrated that the blood flow in the median nerve is reduced when Phalen's test is performed in vivo. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1022–1025, 2010  相似文献   
979.
980.
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