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121.
Catfish hepcidin gene is expressed in a wide range of tissues and exhibits tissue-specific upregulation after bacterial infection 总被引:15,自引:0,他引:15
Antimicrobial peptides (AMPs) are important components of the host innate immune response against microbial invasion. The cysteine-rich AMPs such as defensin and hepcidin have been extensively studied from various organisms, but their role in disease defense in catfish is unknown. As a first step, we sequenced a hepcidin cDNA from both channel catfish and blue catfish, and characterized the channel catfish hepcidin gene. The channel catfish hepcidin gene consists of two introns and three exons that encode a peptide of 96 amino acids. The amino acid sequences and gene organization were conserved between catfish and other organisms. In contrast to its almost exclusive expression in the liver in humans, the channel catfish hepcidin gene was expressed in a wide range of tissues except brain. Its expression was detected early during embryonic and larval development, and induced after bacterial infection with Edwardsiella ictaluri, the causative agent of enteric septicemia of catfish (ESC) in a tissue-specific manner. The upregulation was observed in the spleen and head kidney, but not in the liver. The expression of hepcidin was upregulated 1--3 days after challenge, but returned to normal levels at 7 days after challenge. The expression profile of the catfish hepcidin gene during the course of bacterial infection mirrors those of inflammatory proteins such as chemokines, suggesting an important role for hepcidin during inflammatory responses. 相似文献
122.
ABO血型基因分型及应用 总被引:11,自引:0,他引:11
目的 :研究ABO血型基因分型的意义。方法 :采用聚合酶链反应 序列特异性引物 (PCR SSP)基因定型方法对ABO血型基因定型并观察其基因多态性分布特征和疑难血型检定。结果 :对已知ABO基因的DNA标本进行基因定型 ,证实文中的ABO基因定型方法可靠 ;对 10 4例健康、无血源关系的汉族个体ABO血型基因定型 ,结果与血清学所定表型完全符合 ;并用ABO基因分型技术解决临床输血前血型鉴定、产前胎儿血型鉴定、亲权试验及血清学亚型的正确性验证。结论 :ABO血型基因分型技术可以正确判定ABO血型疑难样本 相似文献
123.
心电信号预处理与心电信号分析 总被引:2,自引:0,他引:2
本文介绍了在一种便携式心电监护仪器中是如何对心电数据进行预处理和智能分析的.为了适应便携式仪器的特征,我们在心电信号预处理中采用了FFT滤波和滑动平均滤波的方法去除各种干扰并使图像得以平滑,同时采用了差分阈值法提取特征点,考虑到监护仪器的实用性,在心电信号分析阶段,我们采用了分析特征间期异常情况的方法来替代对病症的智能诊断功能。 相似文献
124.
The purpose of this study was to establish the range of total serum IgE in a healthy population lacking personal and family history of allergy, as well as the influence of genetic factors (family history of allergy), environmental factors (degree of air pollution), age, and sex on the serum IgE levels. Using a commercial enzyme immunoassay (Phadezym IgE Prist) the mean serum level of IgE was determined in 363 non-atopic children from 0 to 12 years of age. The geometric mean of serum IgE increased according to age, indicating a positive correlation between both. Higher mean values of serum IgE were found for children with a family history of allergy, than for children without (27.82 and 14.49 U/ml respectively). The percentage of variation due to age was about 94.5% in children with no family history of allergy. The mean value of serum IgE increased with the degree of air pollution in the living area (15.49 U/ml in non-polluted areas, 20.78 U/ml in very polluted areas). However, the influence of air pollution was smaller than the influence of family history on the mean values of serum IgE. The mean value of serum IgE was not modified by sex. 相似文献
125.
Mark J Elder MD FRACS FRACO Paul Hiscott PhD FRCS MRCPath John K.G Dart DM FRCS FRCOphth 《Human pathology》1997,28(12):1348-1354
Cicatricial conjunctivitis may be a sequel to systemic disorders (eg, Stevens-Johnson syndrome, cicatricial pemphigoid) or local disorders such as chemical burns. The cicatrisation is often associated with corneal epithelial changes that cause visual loss. These have been attributed to encroachment of the conjunctival epithelium over the cornea. However, the epithelial anomalies are poorly understood. We investigated the corneal epithelial changes in cicatricial conjunctivitis with an immunohistochemical study of intermediate filaments in normal and pathological specimens. Our results show that the normal corneal epithelium is immunoreactive for cytokeratin 3 (CK 3) but not cytokeratin 19 (CK 19), whereas normal conjunctival epithelium is CK 3 negative and CK 19 positive. Conjunctiva artificially transposed over the cornea (after therapeutic conjunctival flap reconstruction) retained the normal pattern of conjunctival cytokeratin expression (CK 3 negative, CK 19 positive). Conversely, the entire corneal epithelium exhibited the normal cytokeratin pattern (CK 3 positive, CK 19 negative) in 82% of Stevens-Johnson, 80% of cicatricial pemphigoid, and 69% of chemical burns specimens. The findings suggest that conjunctival encroachment is not responsible for the changes at the corneal surface in cicatricial conjunctivitis and that the abnormal corneal epithelium is derived from native corneal cells in these diseases. 相似文献
126.
胡萝卜籽挥发油的抗生育作用 总被引:3,自引:0,他引:3
胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。 相似文献
127.
山紫菀与紫菀镇咳祛痰作用的实验研究 总被引:2,自引:0,他引:2
本实验对山紫菀(蹄叶橐吾Ligularia fischeri Turcz.)作了镇咳、祛痰作用的研究,并与紫菀(Aster tataricus L.)在同等条件下进行了比较,它们的浓缩水煎剂均有明显的祛痰作用,而无明显的镇咳作用,二者之间无显著性差异。它们的挥发油乳剂及水煎剂也均未表现出明显的镇咳作用。紫菀挥发油毒性大于山紫菀。 相似文献
128.
The incidence of lung cancer is affected by air pollution, especially in high-density urban areas with heavy road traffic and dense urban form. Several studies have examined the direct relationship between lung cancer incidence and road traffic as well as urban form. However, the results are still inconsistent for high-density urban areas. This study focused on urban form and road traffic, aiming at revealing their relationship with lung cancer incidence in high-density urban areas at the neighborhood level. For this, an ecological study was conducted in downtown Shanghai to identify important indicators and explore quantitative associations. Negative binomial regression was fitted with lung cancer incidence as the dependent variable. The independent variables included indicators for road traffic and urban form, greenness, demographic, and socio-economic factors. The results showed that building coverage, averaged block perimeter area ratio, density of metro station without the glass barrier system, and the percentage of low-quality residential land were positively correlated with lung cancer incidence in the neighborhood, while population density was negatively correlated with lung cancer incidence. This study found a strong self-selection effect of socio-economic factors in the relationship between lung cancer incidence and greenness. These results may be useful for conducting health impact assessments and developing spatial planning interventions for respiratory health in high-density urban areas. 相似文献
129.
目的探究抗菌药物对骨科围术期预防感染的影响。方法选择2016年1月-2019年1月瑞安市人民医院骨科收治的手术患者82例,随机数表法分为对照组和研究组,每组各41例,其中对照组围术期给予常规应用抗菌药物,研究组围术期给予干预性应用抗菌药物,观察两组抗菌药物使用情况、抗菌药物费用,并对抗菌药物使用的合理性进行评价。结果研究组住院时间、手术部位感染、治疗各项费用均低于对照组,差异有统计学意义(P<0.05);两组体温异常情况比较,无统计学差异;两组围术期抗菌药物使用均主要以单一用药为主,研究组单一用药多于对照组,二联用药低于对照组,差异有统计学意义(P<0.05);研究组在抗菌药物品种选择、预防用药时机、术后用药时间等围术期抗菌药物使用合理率均高于对照组,差异有统计学意义(P<0.05);两组治疗前肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、IL-8、C-反应蛋白(CRP)各项血清炎性因子水平比较,无统计学差异;治疗后,两组血清炎性因子水平均下降,差异有统计学意义(P<0.05)。结论干预性应用抗菌药物对骨科围术期预防感染效果显著,在降低手术部位感染发生率的同时,提高抗菌药物使用合理性、缩短住院时间、降低住院费用。 相似文献
130.
目的:探讨大剂量环磷酰胺静脉冲击治疗狼疮性肾炎(LN)的合理方案及对肿瘤坏死因子(TNF)水平的影响,方法:将51例LN患者分为A,B两组,分别给予2周(A组)和4周(B组)一次环磷酰胺静脉冲击治疗(IV-CYC),每次用量0.5-1.0g/m2,同时口服强的松1mg.kg^-1.d^-1。用ELISA双抗体夹心法检测LN患者血清和尿TNF水平。结果:A组病情缓解率显著高于B组(P<0.05),活动期LN患者血清和尿TNF水平显著高于稳定期,轻度肾功不全患者血清TNF水平显著高于肾功正常者(P<0.05),结论:IV-CYC加强的松治疗能显著降低LN患者TNF水平且2周方案优于4周方案,治疗中应根据病情,外周白细胞数和肾功能调整,重症和急进期LN每2周1次,病情轻者可每4周1次,血清和尿TNF的变化有助于监测狼疮活动和肾损害程度。 相似文献