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81.
Liu X  Xu Y  Shen Y  Zhang H  Fu Y  Liu Z  Xu A 《Tissue antigens》2005,65(2):172-177
DPA1 gene is one of the human leukocyte antigen (HLA) class II genes and its promoter is highly polymorphic. From comparative studies among five southern Chinese populations, Jing, Li, Bai, Lahu, and Meizhou Han, we describe their single-nucleotide polymorphism (SNP)/haplotype frequency data of HLA-DPA1 gene promoter in this study. Within the 760-bp promoter region, we have identified 21 SNPs and nine possible haplotypes. Pair-wise comparisons show similar frequencies distribution of the HLA-DPA1 promoter haplotypes among Jing, Li, and Bai, whereas all pair-wise comparisons involved with Lahu or Meizhou Han and other ethnic groups show remarkable difference. The differences in frequencies of HLA-DPA1 promoter alleles may reveal different ethnic origins and demographic histories of the five populations. Our study may help distinguishing each of these populations by sequence variations of HLA-DPA1 promoter, which may be served as functional molecular markers for clinical and immunological studies involving the DPA1 locus.  相似文献   
82.
SARS患者血清IL-8、IL-12和TGF-β1的检测及意义   总被引:5,自引:0,他引:5  
目的 :探讨SARS患者血清IL 8、IL 12和TGF β1在SARS冠状病毒感染致病中的作用。 方法 :应用酶联免疫吸附法 (ELISA)测定广州地区 2 8例SARS冠状病毒感染患者双份血清IL 8、IL 12和TGF β1的水平。实验数据采用两样本均数t检验法。结果 :2 8例SARS冠状病毒感染者血清IL 8水平、病程第 2周IL 12水平比正常健康对照组明显降低 (P <0 0 5 )。SARS冠状病毒感染者血清TGF β1水平与对照组比较无明显差异 (P >0 0 5 )。 结论 :IL 8和IL 12在SARS冠状病毒的致病与免疫过程中可能起降低细胞免疫功能作用  相似文献   
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84.
毛果芸香碱和布林佐胺滴眼液对兔眼表组织的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:探讨抗青光眼药物毛果芸香碱和布林佐胺滴眼液及各自的防腐剂三氯叔丁醇和氯化苯甲烃胺(BAC)对兔眼表组织的影响。方法:选取新西兰大白兔15只,分为正常对照组(3只)、毛果芸香碱组(A组,6只)和布林佐胺组(B组,6只)。用药组右眼使用青光眼药物毛果芸香碱或布林佐胺滴眼液,左眼使用对应的防腐剂三氯叔丁醇或BAC,连续用药30 d。取球结膜组织行苏木素-伊红(HE)染色计数结膜上皮层炎症细胞数;角膜行扫描电镜检测并进行上皮损害分级评分。结果:与正常对照组比较,布林佐胺滴眼液(P<0.01)和防腐剂BAC(P<0.01)导致球结膜上皮层炎症细胞浸润增多;毛果芸香碱滴眼液(P>0.05)和三氯叔丁醇(P>0.05)引起的球结膜炎症细胞增多不明显。布林佐胺滴眼液导致球结膜炎症细胞增加的程度较毛果芸香碱滴眼液严重(P<0.01)。青光眼药物和防腐剂均可导致兔角膜上皮超微结构的损伤,表现为角膜上皮细胞六边形结构变为不规则、边界不清、细胞膜皱缩、细胞间距增宽、上皮细胞表面的微绒毛丢失、细胞空洞和暗细胞增加。布林佐胺滴眼液和BAC引起的角膜损害较毛果芸香碱滴眼液(P<0.01)和三氯叔丁醇明显(P<0.05)。各组左右两眼的球结膜炎症细胞数和角膜损害评分均无显著差异。结论:布林佐胺滴眼液和防腐剂BAC使用1个月后可导致兔球结膜炎症细胞增加和角膜上皮细胞损伤,毛果芸香碱滴眼液和三氯叔丁醇主要引起角膜上皮超微结构的变化;防腐剂是引起眼表损伤的主要原因。布林佐胺滴眼液对兔眼表的损伤较毛果芸香碱滴眼液严重。  相似文献   
85.
Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes. Materials and methods:Isolated rat monocytes were challenged with 10 g/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was analyzed by electrophoretic mobility shift assay (EMSA). Results:LPS provoked a significant calcium elevation and enhanced NF-kappa B activity in monocytes. Ketamine above concentration of 100 M inhibited endotoxin-induced intracellular calcium elevation and NF-kappa B activity. Ketamine itself had no effect on either of them. Conclusions:These findings suggest that ketamine could suppress NF-kappa B in monocytes exposed to endotoxin, and this anti-inflammatory effect might act through attenuating intracellular calcium elevation.Received 31 October 2003; returned for revision 18 December 2003; accepted by I. Ahnfelt-Rønne 26 Januaryy 2004  相似文献   
86.
Previous studies have demonstrated that in the hippocampus the maintenance of long-term potentiation (LTP) requires de novo protein synthesis. To investigate the role of protein synthesis in the maintenance of LTP of C-fiber evoked field potentials in spinal dorsal horn, which may be relevant to hyperalgesia, protein synthesis inhibitor (either cycloheximide or anisomycin) was applied locally to the recording segments of spinal cord in anesthetized rats, 30 min prior to tetanic stimulation to the sciatic nerve. We found that both cycloheximide and anisomycin selectively inhibited late-phase maintenance of the spinal LTP but affected neither LTP induction nor baseline responses of C-fiber evoked field potentials. In the presence of cycloheximide, LTP of C-fiber evoked field potentials was 281.5 +/- 16.5% (n = 6) of baseline 1 h after tetanic stimulation and the potentiation significantly decreased to 235.5 +/- 18.5% at 145 min after tetanic stimulation (P < 0.05). Afterward, LTP of C-fiber evoked field potentials decreased continuously and at 270 min after tetanic stimulation reached 130.8 +/- 18.0%, which was no longer different from baseline (P > 0.05). Spinal application of anisomycin at 30 min before tetanic stimulation yielded similar results (n = 6). These results suggest that protein synthesis may be crucial for the late-phase maintenance of LTP of C-fiber evoked field potentials in spinal dorsal horn.  相似文献   
87.
目的构建基于移动互联网的患者赋能型心衰健康管理平台,促进心衰患者进行自我管理,改善临床结局。方法开展课题研究型品管圈活动,搜集高质量临床证据,构建患者赋能型心衰健康管理平台,通过平台推广与应用,对心衰患者行为进行干预。结果平台应用后,医护人员心衰知识水平显著提升,心衰患者自我护理能力明显提升,患者再入院率、死亡率明显下降,应用效果良好。结论基于移动互联网的患者赋能型心衰健康管理平台是心衰慢性病管理的有效手段。  相似文献   
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89.
《Ticks and Tick》2022,13(6):102027
Grazing domestic ruminants serve as important reservoirs and/or amplificatory hosts in the ecology of tick-borne pathogens (TBPs) and tick vectors in the natural foci; however, many enzootic life cycles including ruminants and ticks are still unknown. This study investigated a wide range of TBPs circulating among ticks and grazing ruminants in the natural foci of Anatolia, Turkey. Tick specimens (n = 1815) were collected from cattle, sheep, and goats in three ecologically distinct areas (wooded, transitional, and semi-arid zones) of Anatolia and identified by species: Dermacentor marginatus, Dermacentor reticulatus, Hyalomma anatolicum, Hyalomma excavatum, Hyalomma marginatum, Hyalomma scupense, Haemaphysalis inermis, Haemaphysalis parva, Haemaphysalis punctata, Haemaphysalis sulcata, Ixodes ricinus, Rhipicephalus bursa, and Rhipicephalus turanicus. PCR-sequencing analyses revealed TBPs of great diversity, with 32 different agents identified in the ticks: six Babesia spp. (Babesia occultans, Babesia crassa, Babesia microti, Babesia rossi, Babesia sp. tavsan1, and Babesia sp. Ucbas); four Theileria spp., including one putative novel species (Theileria annulata, Theileria orientalis, Theileria ovis, and Theileria sp.); one Hepatozoon sp.; four Anaplasma spp., including one novel genotype (Anaplasma phagocytophilum, Anaplasma marginale, Anaplasma ovis, and Anaplasma sp.); six unnamed Ehrlichia spp. genotypes; Neoehrlichia mikurensis; nine spotted fever group rickettsiae, including one putative novel species (Rickettsia aeschlimannii, Rickettsia slovaca, Rickettsia hoogstraalii, Rickettsia monacensis with strain IRS3, Rickettsia mongolitimonae, Rickettsia raoultii, Candidatus Rickettsia goldwasserii, Candidatus Rickettsia barbariae, and Rickettsia sp.); and Borrelia valaisiana. Detailed phylogenetic analyses showed that some of the detected pathogens represent more than one haplotype, potentially relating to the tick species or the host. Additionally, the presence of Neoehrlichia mikurensis, an emerging pathogen for humans, was reported for the first time in Turkey, expanding its geographical distribution. Consequently, this study describes some previously unknown tick-borne protozoan and bacterial species/genotypes and provides informative epidemiological data on TBPs, which are related to animal and human health, serving the one health concept.  相似文献   
90.
《Ticks and Tick》2022,13(6):102038
Dermacentor albipictus is a one-host tick broadly distributed across North America. There are two easily recognizable color variants – ornate and inornate/brown – that have been taxonomically synonymized. Based on mt-cox1 and mt-16S data, there is also evidence for two genetic lineages which do not match the color variants. We present for the first time the complete mitochondrial genomes of the two color variants of D. albipictus including representatives of each lineage. The AT-rich genomes are 14,822 bp – 14,865 bp in length and contain 13 protein coding genes, 2 ribosomal RNA genes and 22 transfer RNA genes, arranged in the conserved type 3 metastriate mitochondrial genome order. The overall differences were 10.66% between the mitochondrial genomes of D. albipictus ornate variant lineage 1 and lineage 2, 10.51% between lineage 1 and inornate/brown variant and 5.87% between lineage 2 and inornate/brown variant. The inornate/brown variant did not form a separate lineage and all inornate isolates were found to belong to lineage 2. Ornate variant isolates occurred in both lineage 1 and 2. The high divergence of the mitochondrial genome suggests that D. albipictus may represent a species complex. Other barcoding genes that may help capture the genetic differences between color and lineage variants include nad1, nad2, nad5, cox1 and atp8 loci. The mtDNA data generated in this study are available in GenBank (Accession numbers: OM678457 - OM678459 and ON032564 - ON032573) for future studies on tick taxonomy, phylogenetics and molecular epidemiology.  相似文献   
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