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991.
目的 运用蛋白质组学的方法,分析正常人及SLE患者血清蛋白质的差异表达,寻找与SLE疾病发病机制相关的蛋白质.方法 分别收集健康人及SLE患者血清各9例,同组血清等量混合,用试剂盒除去血清中的白蛋白和免疫球蛋白,再经除盐浓缩后,将血清样品采用固相pH梯度(IPG)双向凝胶电泳(2-DE)分离正常人及SLE患者血清的总蛋白质.凝胶经考马斯亮蓝染色显色后,利用Analysis2d软件对获得的蛋白图谱进行分析,寻找差异表达的蛋白质,利用基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)进行鉴定,分析差异蛋白点.结果 对照组凝胶共检出蛋白点648个,患者组检出639个.对照组凝胶蛋白点匹配率84.5%,患者组凝胶蛋白点匹配率82.5%.通过比较分析,差异表达蛋白质点数为92个,有52个蛋白点在SLE患者组表达上调,40个表达下调,有14个点的表达水平在组间差异有统计学意义,质谱鉴定共鉴定5个蛋白质.通过文献研究显示,我们鉴定的部分蛋白在SLE的发病机制中起潜在的作用.结论 在SLE患者血清中存在着差异血清蛋白质,这些蛋白质可能是SLE发病的内在因素,并且在SLE的疾病发展过程中发挥重要作用,可能作为新的血清标志物和潜在的自身抗原.  相似文献   
992.
目的采用Meta分析方法定量分析丙戊酸对癫痫患儿骨代谢的影响。方法电子检索中国维普科技期刊数据库、万方数据库、中国知网、中国生物医学文献数据库、EMCC、PubMed、OVID及Cochrance图书馆,纳入丙戊酸对癫痫患儿骨代谢影响的观察性研究,采用NOS量表评估纳入文献的质量。采用RevMan5.2软件进行Meta分析。结果14篇文献(英文10篇,中文4篇)进入Meta分析,均为病例对照研究,累计病例组507例,对照组480例。Meta分析结果显示,丙戊酸对血钙(MD=0.0l,95%CI:-0.05—0.06,P=0.13)、血磷(MD=-0.03,95%CI:-0.19—0.13,P=0.67)、碱性磷酸酶(MD=0.37,95%CI:-19.02~19.77,P=0.97)无明显影响,但丙戊酸组骨密度低于对照组,MD=-0.03,95%CI:-0.06~-0.00,P=0.03;丙戊酸组甲状旁腺激素水平显著高于对照组,MD=4.83,95%CI:1.15~8.50,P=0.01;丙戊酸组25-羟维生素D水平显著低于对照组,MD=-2.46,95%CI:-4.37~-0.55,P=0.01。结论现有证据表明,丙戊酸对癫痢患儿血钙、血磷和ALP无显著影响.但对骨密度、25-OH—VtiD和PTH有影响。  相似文献   
993.
We calculated the light absorbing potential (LAP) of hemoglobin (Hb) and myoglobin (Mb) in mammalian skeletal muscle at rest based on analysis of published chemical and morphometric data (Part 1), interpreted changes in total[Hb + Mb] from NIRS during exercise (Part 2), and estimated the potential contribution of Hb and Mb to changes in NIRS from rest to exercise (Part 3). Part 1: [Hb] in skeletal muscle was estimated from microvascular volume, systemic blood [Hb], and microvascular hematocrit and saturation at rest and during exercise. Part 2: Changes in total[Hb + Mb] (as t[Hb + Mb]) during cycling or knee extension exercise were interpreted using the results of Part 1. Part 3: Using estimates of mean microvascular PO2, Hb and Mb contribution at peak exercise was estimated. Across several species, [Mb] contributed ∼50–70% of the total LAP to NIRS at rest in skeletal muscle. With exercise, increases in t[Hb + Mb] of up to 30% could be entirely explained by the predicted increase in microvascular hematocrit with exercise. Finally, Mb was estimated to contribute ∼70% of the changes in NIRS from rest to peak exercise.  相似文献   
994.
Due to small vessel size, obtaining stable access in pediatric patients is difficult. In addition, because needle stick pain is a concern for patients with chronic illness, central venous catheters are often utilized to provide intravenous treatment. Catheter occlusion is a common complication in pediatric patients and must be addressed to salvage the catheter and ensure successful therapy. The use of fibrinolytics for occlusion treatment have been successful in pediatric populations.  相似文献   
995.
Two hundred forty-six children (96 Whites, of whom 51 were mates; 150 African- Americans, of whom 69 were males) with a familial history of essential hypertension (EH) were re-evaluated 5 years after an initial evaluation. During the initial visit, anthropometric, demographic, and resting cardiovascular (CV) parameters (designated initial baseline levels) were assessed. These CV parameters (systolic and diastolic blood pressure [BP], heart rate, cardiac output index [CI], and total peripheral resistance index [TPRI]) were also measured during postural challenge, a video game challenge, and a cold pressor task. At follow-up, resting CV parameters were again evaluated, and designated as follow-up resting levels. Moderate temporal stability (r range = .43-.56) was observed for all resting CV parameters. Mean stress responses for each CV parameter for all 3 stressors during the initial visit were positively related to the respective CV follow-up resting level. BP stress responses to postural change and video game challenge were found to be significant independent predictors of future resting BP after controlling for standard EH risk factors. Follow-up resting CI was not predicted by any stress responses, whereas follow-up resting TPRI was predicted by TPRI responses to the video game after controlling for standard EH risk Factors. These results contrast with those from an earlier 1-year follow-up. where stress responses for neither CI nor TPRI predicted follow-up resting levels. It appears that, as children get older. TPRI stress responses play a stronger role in vasoconstrictive function. This research was supported by National Institutes of Health Grant HL41781.  相似文献   
996.
In recent years, integrative animal biologists and behavioral scientists have begun to understand the complex interactions between the immune system and the neuroendocrine system. Amphibian metamorphosis offers a unique opportunity to study dramatic hormone-driven changes in the immune system in a compressed time frame. In the South African clawed frog, Xenopus laevis, the larval pattern of immunity is distinct from that of the adult, and metamorphosis marks the transition from one pattern to the other. Climax of metamorphosis is characterized by significant elevations in thyroid hormones, glucocorticoid hormones, and the pituitary hormones, prolactin and growth hormone. Previously, we and others have shown that elevated levels of unbound glucocorticoid hormones found at climax of metamorphosis are associated with a natural decline in lymphocyte numbers, lymphocyte viability, and mitogen-induced proliferation. Here we present evidence that the mechanism for loss of lymphocytes at metamorphosis is glucocorticoid-induced apoptosis. Inhibition of lymphocyte function and loss of lymphocytes in the thymus and spleen are reversible by in vitro or in vivo treatment with the glucocorticoid receptor antagonist, RU486, whereas the mineralocorticoid receptor antagonist, RU26752, is poorly effective. These observations support the hypothesis that loss of larval lymphocytes and changes in lymphocyte function are due to elevated concentrations of glucocorticoids that remove unnecessary lymphocytes to allow for development of immunological tolerance to the new adult-specific antigens that appear as a result of metamorphosis.  相似文献   
997.
<正>P-选择素糖蛋白配体1(P-selectin glycoprotein ligand-1, PSGL-1)是一种主要表达于白细胞及血小板表面的黏附分子,在免疫识别、炎症反应和血栓形成过程中起着重要作用。慢性肾脏病(chronic kidney disease, CKD)的患病率逐年上升,已成为威胁世界公共健康的主要疾病之一,且其病因复杂, 大多数发病机制尚不完全清楚。PSGL-1可通过多种途径参与肾脏疾病的发生发展,其机制可能涉及  相似文献   
998.
999.
Congenital disorders of glycosylation (CDGs) comprise a large number of inherited metabolic defects that affect the biosynthesis and attachment of glycans. CDGs manifest as a broad spectrum of disease, most often including neurodevelopmental and skeletal abnormalities and skin laxity. Two patients with biallelic CSGALNACT1 variants and a mild skeletal dysplasia have been described previously. We investigated two unrelated patients presenting with short stature with advanced bone age, facial dysmorphism, and mild language delay, in whom trio‐exome sequencing identified novel biallelic CSGALNACT1 variants: compound heterozygosity for c.1294G>T (p.Asp432Tyr) and the deletion of exon 4 that includes the start codon in one patient, and homozygosity for c.791A>G (p.Asn264Ser) in the other patient. CSGALNACT1 encodes CSGalNAcT‐1, a key enzyme in the biosynthesis of sulfated glycosaminoglycans chondroitin and dermatan sulfate. Biochemical studies demonstrated significantly reduced CSGalNAcT‐1 activity of the novel missense variants, as reported previously for the p.Pro384Arg variant. Altered levels of chondroitin, dermatan, and heparan sulfate moieties were observed in patients’ fibroblasts compared to controls. Our data indicate that biallelic loss‐of‐function mutations in CSGALNACT1 disturb glycosaminoglycan synthesis and cause a mild skeletal dysplasia with advanced bone age, CSGALNACT1‐CDG.  相似文献   
1000.
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