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151.
目的:探讨激素联合丙种球蛋白治疗小儿重症肌无力的临床疗效及对患儿免疫球蛋白和补体的影响。方法:回顾性分析在我院治疗的70例重症肌无力患儿的临床资料,采用随机序号的方式将其分为观察组和对照组各35例,观察组给予甲泼尼龙联合丙种球蛋白,对照组仅给予甲泼尼龙,观察两组的临床疗效及免疫球蛋白和补体变化情况。结果:观察组总有效率为94.3%明显优于对照组74.3%,两组比较有统计学意义(P〈0.05);观察组症状明显缓解时间(6.55±1.35)d以及总住院天数(17.15±3.65)d较对照组明显缩短,两组比较差异均有统计学意义(P〈0.05)。结论:采用激素联合丙种球蛋白治疗小儿重症肌无力,可以明显改善患者肌无力症状,获得较为满意的临床疗效,值得进一步推广使用。  相似文献   
152.
目的:探讨新生儿肺炎(neonatal pneumonia,NP)的临床表现及x线特征,以提高对NP的临床认识。方法:选择2011年6月至2012年10月在我院确诊为NP的新生儿73例,均经x线检查,回顾性分析患儿的临床资料,总结并分析患儿的临床表现及x线特征。结果:NP患儿的临床症状主要表现为呼吸急促、发绀、咳嗽、吐沫、呛奶和三凹征,部分患儿体温正常;NP的x线影像表现具有多样性,以不同程度的支气管肺炎多见,主要表现为肺纹理增多增密,局部肺野透光度降低或透光度增强。结论:NP患儿的临床症状以呼吸急促、发绀、咳嗽、吐沫、呛奶和三凹征为主,x线检查可为NP的早期诊断提供重要的临床信息,临床医师应根据NP患儿的x线影像的多样性,密切结合患儿的临床症状,做出综合分析。  相似文献   
153.

Objective

Embryo implantation is directly affected by genes related to uterine receptivity. Studies have demonstrated the important roles of miRNAs in the regulation of gene expression. Our early miRNA chip analyses revealed that the mmu-miR-141 expression in endometrial tissue is lower after embryo implantation than before it. However, the possible roles of miR-141 in embryo implantation have not yet been elucidated. Here, mmu-miR-141 was designed to detect the expression and role of miR-141 in the endometria of mice in early pregnancy following embryo implantation.

Methods

Real-time PCR and in-situ hybridization were used to study mmu-miR-141 expression in mouse uterus. Cell proliferation was detected by tetrazolium dye (MTT) assay and flow cytometry. Real-time PCR and Western blot analysis were used to confirm the mRNA and protein levels of phosphatase and tensin homolog (PTEN) to determine whether it was the target gene of mmu-miR-141. Enhanced green fluorescent protein (EGFP) fluorescence reporter vector analysis was also performed. A functional study was performed by injecting mice uteri with mmu-miR-141 inhibitor or mimic vectors.

Results

mmu-miR-141 expression was lower on day 6 (D6) than day 4 (D4) and could be increased by progesterone. Reduced mmu-miR-141 could decrease the proliferation activity of stromal cells and promote apoptosis. Upregulation of mmu-miR-141 inhibited PTEN protein expression but downregulation of mmu-miR-141 increased it, while the mRNA level remained unchanged. EGFP fluorescence reporter vector analysis showed that miR-141 targets the 3′-untranslated region of the PTEN mRNA. In addition, when the physiological mmu-miR-141 level was altered on D2 by injecting with inhibitor or mimic, the embryo implantation sites were significantly decreased on D7.

Conclusions

This study demonstrated that mmu-miR-141 might influence cell proliferation and apoptosis in the endometrium by negatively regulating PTEN expression, and could also influence the number of embryo implantation sites. mmu-miR-141 plays an essential role in embryo implantation.  相似文献   
154.

Background

Low efficiency of gene transfer and silence of transgene expression are the critical factors hampering the development of transgenic livestock. Recently, transfer of recombinant lentivirus has been demonstrated to be an efficient transgene delivery method in various animals. However, the lentiviral transgenesis and the methylation status of transgene in sheep have not been well addressed.

Methodology/Principle Findings

EGFP transgenic sheep were generated by injecting recombinant lentivirus into zygotes. Of the 13 lambs born, 8 carried the EGFP transgene, and its chromosomal integration was identified in all tested tissues. Western blotting showed that GFP was expressed in all transgenic founders and their various tissues. Analysis of CpG methylation status of CMV promoter by bisulfate sequencing unraveled remarkable variation of methylation levels in transgenic sheep. The average methylation levels ranged from 37.6% to 79.1% in the transgenic individuals and 34.7% to 83% in the tested tissues. Correlative analysis of methylation status with GFP expression revealed that the GFP expression level was inversely correlated with methylation density. The similar phenomenon was also observed in tested tissues. Transgene integration determined by Southern blotting presented multiple integrants ranging from 2 to 6 copies in the genome of transgenic sheep.

Conclusions/Significance

Injection of lentiviral transgene into zygotes could be a promising efficient gene delivery system to generate transgenic sheep and achieved widespread transgene expression. The promoter of integrants transferred by lentiviral vector was subjected to dramatic alteration of methylation status and the transgene expression level was inversely correlative with promoter methylation density. Our work illustrated for the first time that generation of transgenic sheep by injecting recombinant lentivirus into zygote could be an efficient tool to improve sheep performance by genetic modification.  相似文献   
155.
玉米螟赤眼蜂Trichogramma ostriniae Pang et Chen是玉米螟的重要卵寄生性天敌,控制适宜的温度有利于室内大规模繁育。本试验以麦蛾卵为寄主,研究了不同温度(18℃、20℃、23℃、25℃、28℃、30℃、33℃、36℃)对玉米螟赤眼蜂的寿命、生殖力、子代羽化率和发育历期的影响。结果表明,20℃-25℃条件下雌蜂寿命最长,达7.9-9.0 d。在18℃-30℃亲代生殖力和子代羽化率无显著差异,亲代产卵量为40.9-61.7粒;羽化率为74.31%-84.22%。玉米螟赤眼蜂从卵到羽化的发育历期随温度的升高而显著缩短,由18℃时的22.6 d缩短至33℃的7.0 d。36℃时,雌蜂的寿命仅为0.56 d,且不能进行正常的生殖活动。因此,室内用麦蛾卵大规模繁育玉米螟赤眼蜂,适宜的温度为28℃-30℃;仅保存蜂种时,可选用温度18℃-20℃。  相似文献   
156.
157.
为了研究标志链带藻(Desmodesmus insignis strain JNU24)在不同Na NO3浓度和不同废水浓度培养下的生长与代谢产物积累状况,评估标志链带藻对废水的处理能力,本研究利用柱状光反应器对标志链带藻进行培养,分别对4种Na NO3浓度的BG-11培养基和4种废水浓度培养下藻细胞的生物量、蛋白质含量、碳水化合物含量和淀粉含量进行了测定。结果显示,在BG-11培养基中,氮浓度为9.0 mmol/L时,藻细胞生物质浓度最高,达6.23 g/L;在废水培养下,未稀释的原废水实验组,其藻细胞生物质浓度最高,达10.31 g/L;75%废水培养下,藻细胞的淀粉含量最高(达50.9%),单位体积藻细胞淀粉含量和产率分别为4.86 g/L和405 mg·L~(-1)·d~(-1),且显著高于不同浓度Na NO3的BG-11培养基组。本研究还测定了标志链带藻对废水中氮、磷的去除效率,结果显示不同浓度废水培养下,氮、磷的去除效率最高可达90.8%和98.7%。基于柱状反应器中的最佳培养效果,以9.0 mmol/L Na NO3的BG-11培养基和75%废水于3.0 cm光径平板光生物反应器中进行室内扩大培养,结果显示在75%废水培养下,藻细胞生物质浓度达9.75 g/L,淀粉单位体积含量和产率分别达到4.75 g/L和230 mg·L~(-1)·d~(-1),且为9.0 mmol/L Na NO3的BG-11培养基培养的3倍。通过沉降特性分析发现,藻细胞收获90 min后均完全沉降,具有较强的沉降性能。本研究标志链带藻能够耐受废水中较高的氮、磷浓度,且对废水中氮、磷有显著的去除作用;该藻能利用废水中的营养成分积累较高的生物量和淀粉含量并且藻细胞能快速沉降,具有极高的经济价值和应用价值,是一株淀粉生产能力较高和废水处理能力较强的极具开发潜力的藻株。  相似文献   
158.
PurposeDevelop and evaluate an electrochemical method to identify healthy individuals, malignant hematopathic patients and solid tumor patients by detecting the leukocytes in whole-blood.MethodsA total of 114 individual blood samples obtained from our affiliated hospital in China (June 2015- August 2015) were divided into three groups: healthy individuals (n = 35), hematologic malignancies (n = 41) and solid tumors (n = 38). An electrochemical workstation system was used to measure differential pulse voltammetry due to the different electrochemical behaviors of leukocytes in blood samples. Then, one-way analysis of variance (ANOVA) was applied to analyze the scanning curves and to compare the peak potential and peak current.ResultsThe scanning curve demonstrated the specific electrochemical behaviors of the blank potassium ferricyanide solution and that mixed with blood samples in different groups. Significant differences in mean peak potentials of mixture and shifts (ΔEp (mV)) were observed of the three groups (P< = 0.001). 106.00±9.00 and 3.14±7.48 for Group healthy individuals, 120.90±11.18 and 18.10±8.81 for Group hematologic malignancies, 136.84±11.53 and 32.89±10.50 for Group solid tumors, respectively. In contrast, there were no significant differences in the peak currents and shifts.ConclusionsThe newly developed method to apply the electrochemical workstation system to identify hematologic malignancies and solid tumors with good sensitivity and specificity might be effective, suggesting a potential utility in clinical application.  相似文献   
159.

Objective

Dogs, like humans, experience eye changes with aging: hardening and clouding of the lens and accumulated oxidative damage from UV sunlight. It has been debated whether such changes could be affecting the visual function of dogs. The objective of this study was to determine if autorefractometry could be used to measure visual function in dogs.

Animals and Methods

Nine Beagle dogs (ages 1 to 14 years) were examined by a veterinary ophthalmologist and their eyes determined to be free of cataracts. Spherical equivalent refractive error was measured by handheld autorefractor (Welch Allyn SureSight) under both indirect and direct lighting conditions with five measurements per condition, per eye. Measures were repeated on three different days for each dog within six weeks. Nonparametric statistics were used to detect differences among lighting conditions and test days, and between eyes. Spearmen correlation assessed the visual measurement outcomes’ association with age.

Results

There was no difference for day-to-day or between-eye measurements. Significantly, the Beagles showed a myopic shift with aging (average spherical equivalent ranged from plano to -3.00 diopters), suggesting that dogs become more near-sighted as they age (r = -0.48 and -0.73 under direct and indirect lights; p<0.05 both). Younger dogs were able to make larger accommodation changes from indirect light to direct light conditions, indicating a more flexible lens (r = -0.50, p<0.05).

Conclusions

Although designed for humans, the hand-held autorefractor technique is applicable to dogs and sensitive to light conditions. The age-associated myopic shift could be expected to compromise dogs’ visual functions.  相似文献   
160.
Microglial-mediated neuroinflammation has been established as playing a vital role in pathogenesis of neurodegenerative disorders. Thus, rational regulation of microglia functions to inhibit inflammation injury may be a logical and promising approach to neurodegenerative disease therapy. The purposes of the present study were to explore the neuroprotective effects and potential molecular mechanism of Schizandrin A (Sch A), a lignin compound isolated from Schisandra chinesnesis. Our observations showed that Sch A could significantly down-regulate the increased production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-6 induced by lipopolysaccharide (LPS) both in BV-2 cells and primary microglia cells. Moreover, Sch A exerted obvious neuroprotective effects against inflammatory injury in neurons when exposed to microglia-conditioned medium. Investigations of the mechanism showed the anti-inflammatory effect of Sch A involved the inhibition of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) expression levels and inhibition of the LPS-induced TRAF6-IKKβ-NF-κB pathway. Furthermore, inhibition of Jak2-Stat3 pathway activation and Stat3 nuclear translocation also was observed. In conclusion, SchA can exert anti-inflammatory and neuroprotective effects by alleviating microglia-mediated neuroinflammation injury through inhibiting the TRAF6-IKKβ-NF-κB and Jak2-Stat3 signaling pathways.  相似文献   
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