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排序方式: 共有660条查询结果,搜索用时 15 毫秒
1.
Hoon-Chul Kang Ji Won Kwon Young Mock Lee Heung Dong Kim Hong Jin Lee Si Houn Hahn 《Child's nervous system》2007,23(11):1301-1307
OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses. 相似文献
2.
目的 探讨常年性变应性鼻炎 (PAR)患者细胞免疫功能状态及微波凝固治疗的作用机制。方法 观察组 2 5例PAR患者分别于微波治疗前以及治疗 1个月后应用免疫组化法检测鼻粘膜上皮和外周血CD3、CD4、CD8、CD4/CD8水平。健康对照组 1 5例亦作相应检测。结果 PAR患者治疗前鼻粘膜及外周血CD3、CD4明显高于正常人 ,CD8低于正常人 ,CD4/CD8比值升高 ,与正常人比较差异有显著性 (P <0 .0 5)。微波治疗后CD4明显减少 ,CD8升高 ,CD4/CD8接近于健康对照组。结论 PAR患者存在明显的细胞免疫功能障碍 ;微波局部凝固治疗可改善PAR患者的细胞免疫状况。 相似文献
3.
[目的] 通过两样本孟德尔随机化设计,探讨睡眠与痛风之间的关联。[方法] 从一项包含763 813名参与者的全基因组关联研究(genome-wide association study,GWAS)中获取痛风遗传关联数据。以与打鼾、睡眠时间、睡眠类型、失眠及白日困倦程度等睡眠表型相关的单核苷酸多态性(single nucleotide polymorphism,SNP)作为工具变量,采用逆方差加权(inverse variance weighted,IVW)评估遗传学预测的不同睡眠表型与痛风发生风险的关系。采用MR-Egger回归和孟德尔随机多态性残差和离群值(MR pleiotropy residual sum and outlier,MR-PRESSO)检验进行敏感性分析,以评估工具变量的多效性。进一步采用加权中位数法、简单中位数法、最大似然比法等分析方法检验结果的稳健性与可靠性。[结果] IVW结果显示,遗传学预测的打鼾[优势比(odds ratio,OR)=3.12,95%置信区间(confidence interval,CI)(1.21~8.05),PFDR=0.045]和失眠[OR=1.09,95%CI(1.04~1.15),PFDR=0.005]与痛风发生风险呈正相关,而睡眠时间、睡眠类型及白日困倦程度与痛风发生之间不存在统计学关联。MR-Egger回归提示上述因果关联未受到水平多效性影响,加权中位数法、简单中位数法、最大似然比法得出与IVW相似的结果。[结论] 打鼾、失眠与痛风发生风险呈正相关,纠正打鼾和失眠可能对痛风有一定的预防作用。 相似文献
4.
人体恶性实体瘤TIL增殖力、表型和杀伤力研究 总被引:4,自引:0,他引:4
在建立高活力肿瘤浸润淋巴细胞(TIL)分离培养方法的基础上,对83例恶性实体瘤TIL的细胞增殖动力学、部份TIL表型与杀伤力等作了较为系统的研究。结果提示,本实验室所建立分离培养的TIL增殖能力较强且稳定,有65%的增殖倍数大于1000倍;3H-TdR掺入高峰在培养的第45~75天;对其自身的原代肿瘤细胞杀伤力可以维持至56天以上;对56份经rIL2诱导的TIL(培养时间17±5.2天)表型分析:CD380±21%,CD437±21%,CD844±18%,HLADR69±24%,与rIL2诱导前比较,CD3、CD4、CD8和HLADR均增多,尤以CD3与CD8表型增多明显。 相似文献
5.
Mahmoud I. Abdel-Aziz Paul Brinkman Susanne J.H. Vijverberg Anne H. Neerincx John H. Riley Stewart Bates Simone Hashimoto Nazanin Zounemat Kermani Kian Fan Chung Ratko Djukanovic Sven-Erik Dahlén Ian M. Adcock Peter H. Howarth Peter J. Sterk Aletta D. Kraneveld Anke H. Maitland-van der Zee 《The Journal of allergy and clinical immunology》2021,147(1):123-134
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6.
7.
Edmond A. Murphy 《American journal of medical genetics. Part A》1993,45(3):383-391
This paper explores properties of discrete processes in which a pursuer seeks a target that is moving at constant velocity r that is a fixed proportion of the speed of the pursuer. The pursuer is subjected to proportional angular homeostasis, so chosen that the number of steps per circuit is small. The orbits relative to the target may assume any of four forms: polygons that reverse their sense an infinite number of times; or polygons that after a finite number of reversals ultimately come to have an integer numbers of sides; or have a rational numbers of sides; or have an irrational number of sides that densely fill an annulus. None of the polygons is regular. In the parameter space, the boundary line between the first of these sets and the other three has a somewhat bizarre pattern and may possibly be fractal, but no proof is forthcoming. Unlike the pattern with a stationary target, there may be a set or catchment of diverse values of the speed ratio, r, and the correction coefficient, b that all result in figures of some specified number, n, of sides (although with vertices in differing locations). Catchments have been found for only those polygons that have the winding number of 1. The implications are discussed that this property has for the genetic coding of biological traits that are countable. Some attention is also paid to the relevance of polygons with few sides to ontogenic growth when the correction coefficient is cyclically arc- or time-dependent. © 1993 Wiley-Liss, Inc. 相似文献
8.
A racial difference in apolipoprotein E allele frequencies between the Japanese and Caucasian populations 总被引:2,自引:0,他引:2
We have examined the apo E phenotype frequencies in the Japanese population (n = 576, 16-78 years of age). Apo E phenotypes were determined by the rapid flat gel isoelectric focusing method that we previously reported. The apo E phenotype frequencies in the Japanese were 0.3% for E2/2, 6.1% for E3/2, 71.9% for E3/3, 0.7% for E4/2, 19.3% for E4/3 and 1.7% for E4/4. The apo E allele frequencies were 0.037, 0.846 and 0.117 for the epsilon 2, epsilon 3 and epsilon 4 alleles, respectively. These frequencies were compared with those in the Caucasian populations (n = 3033) reported by Sing & Davignon (1985). There was a significant difference in the apo E phenotype frequencies between the Japanese and Caucasian populations. In addition, a significantly lower frequency of the epsilon 2 and epsilon 4 alleles and a significantly higher frequency of the epsilon 3 allele were found in the Japanese than those reported for the Caucasian populations. It is concluded that there is a racial difference in the apo E allele frequencies between the Japanese and Caucasian populations. 相似文献
9.
The regulatory mechanisms that monitor the size of the peripheral B cell pool and determine cell death or survival are poorly understood. In rodents B lymphopoiesis is maintained at a high rate throughout adult life, and under resting conditions there is little recruitment into the long-lived peripheral pool; it therefore follows that most newly formed B lymphocytes have a very short lifespan. The maturation stages of B lymphopoiesis in humans and in experimental mammals appear to be similar. We have determined the phenotype of sIgM- and sIgD-expressing cells from normal adult human bone-marrow and peripheral blood by dual immunofluorescence with an extensive panel of monoclonal antibodies representative of major B cell clusters, in order to identify antigenic differences that may play a regulatory role. Antibodies of the CD21, CD22 and CD9 clusters, the unclustered restricted B antibody 7-F-7 and anti-IgD were reactive with different proportions of sIgM+ cells in blood and bone marrow; 29.5% (range 5-60%) of sIgM+ cells in marrow were sIgD- and most of these cells were also CD21- and CD22-, thus defining a unique marrow population. However, newly formed and mature re-circulating cells comprising the sIgM+sIgD+ population could not be distinguished by the panel of antibodies. 相似文献
10.
Nikolay M Filipov Lesya M Pinchuk Bobbie L Boyd Patrick L Crittenden 《Toxicological sciences》2005,86(2):324-332
The herbicide atrazine (ATR) is a very widely used pesticide; yet the immunotoxicological potential of ATR has not been studied extensively. Our objective was to examine the effect of ATR on selected immune parameters in juvenile mice. ATR (up to 250 mg/kg) was administered by oral gavage for 14 days to one-month-old male C57BL/6 mice. One day, one week, and seven weeks after the last ATR dose, mice were sacrificed, and blood, spleens, and thymuses were collected and processed for cell counting and flow cytometry. Thymus and spleen weights were decreased by ATR, with the thymus being more sensitive than the spleen; this effect was still present at seven days, but not at seven weeks after the last ATR dose. Similarly, organ cellularity was persistently decreased in the thymus and in the spleen, with the splenic, but not thymic cellularity still being depressed at seven weeks post ATR. Peripheral blood leukocyte counts were not affected by ATR. There were also alterations in the cell phenotypes in that ATR exposure decreased all phenotypes in the thymus, with the number of CD4(+)/CD8(+) being affected the least. At the higher doses, the decreases in the thymic T-cell populations were still present one week after the last ATR dose. In the spleen, the CD8(+) were increased and MHC-II(+) and CD19(+) cells were decreased one day after the last ATR dose. Also, ATR treatment decreased the number of splenic na?ve T helper and T cytotoxic cells, whereas it increased the percentage of highly activated cytotoxic/memory T cells. Interestingly, the proportion of mature splenic dendritic cells (DC; CD11c(high)), was also decreased and it persisted for at least one week, suggesting that ATR inhibited DC maturation. In the circulation, ATR exposure decreased CD4(+) lymphocytes at one day, whereas at seven days after the last ATR dose, in addition to the decrease in CD4(+) lymphocytes, the MHC-II(+) cells were also decreased at the 250 mg/kg dose. Thus, ATR exposure appears to be detrimental to the immune system of juvenile mice by decreasing cellularity and affecting lymphocyte distribution, with certain effects persisting long after exposure has been terminated. 相似文献