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311.
W-3Bao是本研究组通过诱变获得、Kit无义突变的白斑小鼠。突变基因杂合子小鼠腹部、四肢肢端及尾尖白化,其部分精曲小管内无精原细胞。突变纯合子小鼠在胚胎后期色泽苍白、个体矮小,于出生前后死亡;血液学检查发现纯合子小鼠血色素极低且红细胞变大;18.5天胚胎的连续切片可见精曲小管轮廓欠清晰,精原细胞分散分布于睾丸间质,未迁入精曲小管;卵巢结构紊乱,无明显的原始卵泡结构;骨髓等器官组织未见显著异常。结论:Kit无义突变不仅导致了W-3Bao杂合子小鼠白斑形成及纯合子小鼠贫血死亡,同时影响生殖腺发育。  相似文献   
312.
Ding Y  Sun X  Xu X 《Autophagy》2012,8(1):142-143
The target of rapamycin (TOR) kinase is part of an evolutionarily conserved signaling pathway that coordinates cell growth, survival, and autophagy. Previously, pharmacological studies using rapamycin have suggested a cardioprotective effect of TOR signaling inhibition on cardiomyopathy. We found that rapamycin exerts a conserved cardioprotective effect in two adult zebrafish models of cardiomyopathy of different etiology, and provided the first genetic evidence to support a long-term cardioprotective effect of TOR signaling inhibition. Moreover, we detected dynamic TOR-autophagy activities along different stages of cardiomyopathy. This needs to be considered when developing TOR-autophagy-based therapeutics for cardiomyopathy.  相似文献   
313.
314.
Sugahara R  Mon H  Lee JM  Kusakabe T 《Gene》2012,501(2):180-187
The Fanconi anemia (FA) pathway is required for activation and operation of the DNA interstrand cross-link (ICL) repair pathway, although the precise mechanism of the FA pathway remains largely unknown. A critical step in the FA pathway is the monoubiquitination of FANCD2 catalyzed by a FA core complex. This modification appears to allow FANCD2 to coordinate ICL repair with other DNA repair proteins on chromatin. Silkworm, Bombyx mori, lacks apparent homologues of the FA core complex. However, BmFancD2 and BmFancI, the putative substrates of the complex, and BmFancL, the putative catalytic E3 ubiquitin ligase, are conserved. Here, we report that the silkworm FancD2 is monoubiquitinated depending on FancI and FancL, and stabilized on chromatin, following MMC treatment. A substitution of BmFancD2 at lysine 519 to arginine abolishes the monoubiquitination, but not the interaction between the FancD2 and FancI. In addition, we demonstrated that depletion of BmFancD2, BmFancI or BmFancL had effects on cell proliferation in the presence of MMC. These results suggest that the FA pathway in B. mori works in the same manner as that in vertebrates.  相似文献   
315.
目的探讨荧光定量PCR检测技术对SPF鸡四种垂直传播病毒的检测应用。方法采集60份SPF鸡及70份普通鸡群蛋清、泄殖腔试子样品,提取样品核酸,分别进行ARV、REV、CAV、ALV四种病毒实时荧光定量PCR检测,根据标准曲线及溶解曲线分析判读样品病毒拷贝数。结果 SPF鸡ALV 2份阳性,检出率3.3%,其余病毒检测均为阴性;普通鸡样品REV检测2份阳性,检出率2.9%,ALV 10份阳性,检出率14.3%。结论荧光定量PCR检测方法最低可检测到100个拷贝核酸,检测灵敏度较高,有望应用于SPF鸡临床样品的病原检测。  相似文献   
316.
Because micronutrients in human diets ultimately come from plant sources, malnutrition of essential minerals is a significant public health concern. By increasing the expression of nicotianamine synthase (NAS), we fortified the level of bioavailable iron in rice seeds. Activation of iron deficiency-inducible OsNAS2 resulted in a rise in Fe content (3.0-fold) in mature seeds. Its ectopic expression also increased that content. Enhanced expression led to higher tolerance of Fe deficiency and better growth under elevated pH. Mice fed with OsNAS2-D1 seeds recovered more rapidly from anemia, indicating that bioavailable Fe contents were improved by this increase in OsNAS2 expression.  相似文献   
317.
目的:探讨中药血复生联合西药治疗慢性再生障碍性贫血(CAA)的临床效果,及对造血、细胞免疫功能和血清IL-2、IFN-γ的影响。方法:将54例慢性再生障碍性贫血分为联合治疗组与对照组,其中对照组给予西药常规治疗,联合治疗组在此基础上加用血复生,通过观察治疗前后患者临床症状、外周血象、T-淋巴细胞亚群和血清IL-2、IFN-γ水平变化,比较两组疗效。结果:联合治疗组总有效率为88.24%,显著高于对照组65.00%的总有效率(P<0.01),联合治疗组在症状改善、升高全血细胞、调节T-淋巴细胞亚群和降低血清IL-2、IFN-γ水平等方面作用优于对照组(P<0.01或0.05),且不良反应少。结论:血复生联合西药可促进CAA患者造血细胞增殖,调节细胞免疫功能,效果好于单用西药。  相似文献   
318.
This review summarizes the articles published on Helicobacter pylori infection in children between April 2008 and March 2009. Recent evidence highlights the decreasing prevalence trend of H. pylori infection and supports both intrafamilial and extrafamilial transmission. The association with various symptoms is still being debated. Interestingly, H. pylori infection seems inversely associated with allergic diseases. Monoclonal stool antigen tests are widely used and accurate for the diagnosis of H. pylori infection, but less accurate in young children. The new biprobe real-time PCR assay applied to stools showed a poor sensitivity in children. Using the urea hydrolysis rate next to the delta over baseline values, the 13C-urea breath test provides excellent results for all age children, even for young children. Treatment of H. pylori infection remains a challenge, considering suboptimal efficacy of current therapy. Among emerging alternatives, sequential treatment appears promising. The adjunction of probiotics to conventional regimens, although eliciting great interest, has shown limited therapeutic benefit.  相似文献   
319.
For two decades, Helicobacter pylori has been considered as the culprit in many extragastric manifestations. However, for several of these supposed associations the hypothesis of an etiological role has not yet been fully investigated. This may be due to a series of factors linked to the epidemiological features of the studies and to the diseases investigated. This review attempts to highlight the main reported associations of H. pylori with extragastric manifestations during the last year. The most convincing data arise in the field of idiopathic thrombocytopenic purpura (ITP) and sideropenic anemia. Long-term follow-up studies have shown that 50% of subjects with ITP maintain a hematological response after H. pylori eradication. There is also growing evidence of the role of H. pylori in other diseases, including ischemic heart disease even though results are not conclusive.  相似文献   
320.
This study was designed to measure the effects of iron supplementation on respiratory burst in iron-deficient anemia. The performance of neutrophils was evaluated by measuring the activity of NADPH oxidase in 18 patients with iron-deficient anemia before and after body iron stores are saturated. The activity of NADPH oxidase was significantly lower in pretreatment patients relative to controls (p<0.05). The activity increased after iron supplementation to levels that had no significant differences relative to controls.  相似文献   
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