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91.
摘要 目的:探讨罗沙司他治疗肾性贫血的效果观察及对转铁蛋白饱和度(TSAT)、胱抑素C(Cys C)及NADPH氧化酶2(NOX2)的作用。方法:选择2019年12月到2020年12月在我院接受治疗的125例肾性贫血患者,采用随机数表法分为试验组(n=63)和对照组(n=62)。对照组给予重组人促红素治疗,试验组给予罗沙司他治疗。比较两组临床疗效、TSAT、Cys C、NOX2、红细胞计数(RBC)、血红蛋白(Hb)、血细胞比容(Hct)、铁蛋白(SF)、转铁蛋白(TRF)及铁调素(Hepc)水平变化情况及药物不良反应发生情况。结果:治疗后,两组总有效率比较差异显著(P<0.05);治疗前,试验组和对照组血清TSAT、Cys C及NOX2比较无显著差异;治疗后,试验组和对照组血清TSAT随着时间的推移而升高,且试验组高于对照组,Cys C及NOX2随着时间的推移而升减降低,且试验组低于对照组,差异显著(P<0.05);治疗前,试验组和对照组RBC、Hb、Hct检验结果比较无显著差异;治疗后,试验组和对照组RBC、Hb、Hct均随着时间的推移而升高,且试验组高于对照组,差异显著(P<0.05);治疗前,试验组和对照组SF、TRF及Hepc检验结果比较无显著差异;治疗后,试验组和对照组血清SF、TRF均随着时间的推移而升高,且试验组高于对照组,Hepc随着时间的推移而下降,且试验组低于对照组,差异显著(P<0.05);两组不良反应总发生率分别为4.76%、8.06%(P>0.05)。结论:在肾性贫血患者中应用罗沙司他效果显著,可能与其可有效改善血清TSAT、Cys C及NOX2水平有关,且不增加不良反应。  相似文献   
92.
再生障碍性贫血(aplastic anemia,AA)是由于物理、化学、生物或不明因素作用使骨髓造血干细胞和骨髓微环境严重受损,造成骨髓造血功能降低或衰竭,以全血细胞减少为主要表现的一组综合征。间充质干细胞(MSC)是属于中胚层的一类多能干细胞,主要存在于结缔组织和器官间质中。不仅具有多向分化潜能,还有多种免疫调节作用。许多研究表明MSCs抑制同种异体效应T淋巴细胞增殖,还能下调T淋巴细胞表面的活化分子CD25、CD38、CD69的表达。MSCs对DCs的分化、成熟和活化具有抑制作用,改变DCs的细胞因子分泌,使成熟的DCl分泌TNF-a减少,DC2分泌IL-10增加,从而抑制T淋巴细胞增殖。MSCs能够抑制IL-2和IL-15介导的NK细胞增殖,使IL-2刺激NK细胞分泌的IFN-y减少。通过这些机制来干预再生障碍性贫血,同时研究发现MSCs免疫原性较低。尤其脐带MSC,因为其独特优势,目前已经成为干细胞干预治疗AA的研究热点。  相似文献   
93.
马传染性贫血病毒(Equine infectious anemia virus,EIAV)是反转录病毒科慢病毒属的成员,是马传染性贫血病的病原.二十世纪七十年代我国就研制出马传染性贫血驴白细胞弱毒疫苗,成为世界第一个成功地应用该疫苗控制了我国的马传贫的发生[1].而且我国的马传贫弱毒疫苗对异源的美国、古巴和阿根廷等毒株也有很高的保护率[2].因此将我国的马传贫驴细胞弱毒疫苗推向国际市场成为可能.然而目前制约该苗出口的技术问题是现行的OIE推荐的琼脂扩散实验和ELISA等血清学方法不能鉴别自然感染马与我国弱毒疫苗免疫马,针对这个关键问题,本试验采用PCR方法初步建立了一种能够鉴别美洲(美国和阿根廷)流行毒株感染马和我国弱毒疫苗免疫马的实验室检测方法,为我国疫苗能在世界范围内应用提供了配套技术.  相似文献   
94.
鸡贫血病毒SJ1株DNA的分子克隆   总被引:1,自引:0,他引:1  
通过PCR方法扩增,用pUC119和pBluescriptSK质粒载体分段克隆了山东省分离的SJ1株的全病毒DNA。限制性内切酶酶切分析结果显示其与国际标准株的酶谱相似  相似文献   
95.
BackgroundHbS/b cases having clinical, hematologic and electrophoretic similarities cannot be sufficiently distinguished from sickle cell anemia cases and are misdiagnosed as sickle cell anemia. This study will investigate the congruence between the HPLC thalassemia scanning tests and the laboratory findings compared to the DNA sequence analysis results of the patients diagnosed with SCA between 2016 and 2020. This study also aims to indicate the current status to accurately diagnose sickle cell anemia and HbS/b in the light of hematologic, electrophoretic and molecular studies.MethodsFourteen patients who were diagnosed with SCA in hospitals at different cities in Turkey and followed by the Thalassemia Diagnosis, Treatment and Research Center, Muğla Sıtkı Koçman University were included in this retrospective study. The socio-demographic characteristics, hemogram, hemoglobin variant analysis results and DNA chain analysis results of the patients were taken from the database of the centre and then examined. The informed consents were taken from the patients. The patients were administered a survey containing questions about transfusion history and diagnostic awareness. The Beta-Thalassemia mutations were analysed using a DNA sequencer (Dade Behring, Germany) based on the Sanger method.ResultsAccording to the DNA sequence analysis, the results of these patients diagnosed with SCA in hospitals in different cities of Turkey were the following: of 14 patients, 8 had HbS/b0, and HbS/b+ and one had HbS carrier, and one had Hb-O, and three had SCA. The patient with HbS carrier status also contains three additional mutations, all of which are heterozygous. We discovered that although two of three mutations, which are c.315+16G>C and c.316-185C>T, are previously reported as benign, at least one of the two mentioned mutations, when combined with HbS, causes transfusion-dependent HbS/b.ConclusionsBriefly, HbSS and HbS/b thalassemia genotypes cannot be definitely characterized by electrophoretic and hematologic data, resulting in misdiagnosis. c.315+16G>C and c.316-185C>T are previously reported as benign; at least one of the two mentioned mutations, when combined with HbS, causes transfusion-dependent HbS/b. In undeveloped or some developing countries, molecular diagnosis methods and genetic analyses cannot be used. If mutation analyses could be performed, then such differential diagnosis errors would reduce. However, if mutation analysis cannot be performed, other methods such as HPLC, capillary electrophoresis absolutely be sought to have insight into the parental carriage status.  相似文献   
96.
We propose a new mathematical model of erythropoiesis that takes a positive feedback of erythrocytes on progenitor apoptosis into account, and incorporates a negative feedback of erythrocytes on progenitor self-renewal. The resulting model is a system of age-structured equations that reduces to a system of delay differential equations where the delays account for progenitor compartment duration and cell cycle length. We compare this model with experimental data on an induced-anemia in mice that exhibit damped oscillations of the hematocrit before it returns to equilibrium. When we assume no self-renewal of progenitors, we obtain an inaccurate fitting of the model with experimental data. Adding self-renewal in the progenitor compartment gives better approximations, with the main features of experimental data correctly fitted. Our results indicate the importance of progenitor self-renewal in the modelling of erythropoiesis. Moreover, the model makes testable predictions on the lifespan of erythrocytes confronted to a severe anemia, and on the progenitors behavior.  相似文献   
97.
In order to evaluate serum copper and zinc status in children with iron deficiency anemia (IDA), 60 children with IDA aged 1–14 yr and 64 healthy children as controls aged 1–14 yr were included the study. Serum copper levels were higher in children with IDA (189 ± 49 (Μg/dL) than those of controls (163 ± 37 Μg/dL) (p = 0.001). Serum zinc levels were lower in the patient group (109 ± 59 Μg/dL) than those of control subjects (135 ± 56 Μg/dL) (p = 0.017). In addition, there were statistically significant negative correlations between hematological parameters and serum copper levels in the patient group, but not in controls. No correlation between hematological parameters and serum zinc levels were found in both patient and control groups, except positive correlation between mean corpuscular volume (MCV) and serum zinc level in patients. It was concluded that at the time of managing children with IDA, zinc deficiency must be borne in mind and if necessary treatment should be initiated with zinc.  相似文献   
98.
A salmonid alphavirus (SAV)-based replicon encoding the infectious salmon anemia virus (ISAV) hemagglutinin-esterase (HE), pSAV/HE, is an efficacious vaccine against infectious salmon anemia (ISA). Delivered intramuscularly (i.m.), the replicon vaccine provides high protection against subsequent ISAV challenge in Atlantic salmon (Salmo salar), and induces a strong innate response locally at the injection site. This may be beneficial and could warrant reduced doses and improved efficacy compared to conventional DNA vaccines. In the present study, we found that intraperitoneal (i.p.) administration of the pSAV/HE replicon vaccine did not induce protection, neither alone or in combination with a sub-potent, inactivated low-dose ISAV vaccine given i.p. No significant differences between the two immunization routes regarding systemic immune responses could be observed. I.m. injection of the replicon vector encoding a non-viral gene or the protective glycoprotein (G protein) from the heterologous viral hemorrhagic septicemia virus (VHSV) induced no protection against ISA. Although the replicons without the ISAV HE did induce IFN-signaling pathways at the muscle injection site similar to the pSAV/HE replicon they did not improve the efficacy of a sub-potent inactivated low-dose ISAV vaccine delivered i.p. Moreover, there was a tendency for reduced efficacy of the pSAV/HE replicon vaccine injected i.m. when co-injected with the replicon encoding the VHSV G protein, which previously, after DNA vaccination, have been reported to induce cross-protection against heterologous virus challenge in fish.  相似文献   
99.
100.
FANCD2 is required for the repair of DNA damage by the FA (Fanconi anemia) pathway, and, consequently, FANCD2-deficient cells are sensitive to compounds such as cisplatin and formaldehyde that induce DNA:DNA and DNA:protein crosslinks, respectively. The DNA2 helicase/nuclease is required for RNA/DNA flap removal from Okazaki fragments during DNA replication and for the resection of DSBs (double-strand breaks) during HDR (homology-directed repair) of replication stress-induced damage. A knockdown of DNA2 renders normal cells as sensitive to cisplatin (in the absence of EXO1) and to formaldehyde (even in the presence of EXO1) as FANCD2−/− cells. Surprisingly, however, the depletion of DNA2 in FANCD2-deficient cells rescues the sensitivity of FANCD2−/− cells to cisplatin and formaldehyde. We previously showed that the resection activity of DNA2 acts downstream of FANCD2 to insure HDR of the DSBs arising when replication forks encounter ICL (interstrand crosslink) damage. The suppression of FANCD2−/− by DNA2 knockdowns suggests that DNA2 and FANCD2 also have antagonistic roles: in the absence of FANCD2, DNA2 somehow corrupts repair. To demonstrate that DNA2 is deleterious to crosslink repair, we used psoralen-induced ICL damage to trigger the repair of a site-specific crosslink in a GFP reporter and observed that “over-resection” can account for reduced repair. Our work demonstrates that excessive resection can lead to genome instability and shows that strict regulatory processes have evolved to inhibit resection nucleases. The suppression of FANCD2−/− phenotypes by DNA2 depletion may have implications for FA therapies and for the use of ICL-inducing agents in chemotherapy.  相似文献   
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