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91.
中心体蛋白Cenexin是成熟中心粒的唯一标志分子。为阐明中心粒在大鼠精子发生中的成熟以及功能,我们首先通过RT-PCR技术从大鼠睾丸组织中扩增出了Cenexin cDNA片段,原核表达重组蛋白后,用其免疫小鼠制备了高滴度的抗Cenexin的多克隆抗体,然后利用免疫荧光染色、Western Blot和半定量RT-PCR方法,研究了大鼠精子发生过程中Cenexin蛋白和基因的表达特征。结果显示Cenexin mRNA水平在精原细胞和精母细胞中较高,随后表达水平下降,而蛋白质分子在精原细胞到精子细胞中都定位于细胞的一个中心粒上,表示有成熟中心粒的存在,在长形精子细胞中该蛋白位于鞭毛的基体部。附睾的绝大多数成熟精子中Cenexin免疫染色消失。中心体蛋白Cenexin在精子变态期的表达变化可能与精子鞭毛形成的起始有关。 相似文献
92.
Juan Li Tianyi Krupka Jinpeng Yao Ronghui Wang Lin Jiang Yang Zhou Guoqing Zuo Zhibiao Wang Lili Dai Jianli Ren Yuanyi Zheng Dong Wang 《PloS one》2015,10(2)
BackgroundHIFU has been shown to be a more suitable alternative for the treatment of primary solid tumors and metastatic diseases than other focal heat ablation techniques due to its noninvasive and extracorporeal nature. However, similar to other focal heat ablation techniques, HIFU is still in need of refinements due to tumor recurrence.MethodsIn this work, we investigated the effectiveness of an adjunct treatment regimen using doxorubicin (DOX)-loaded, injectable, in situ-forming, and phase-inverting PLGA as the second line of defense after HIFU ablation to destroy detrimental residual tumors and to prevent tumor recurrence. All of the statistical analyses were performed using the Statistical Package for the Social Sciences 18.0(SPSS, Inc., Chicago, IL, USA), and p< 0.05 was considered statistically significant. All of the results are presented as the means ± STDEV (standard deviation). For multiple comparisons, ANOVA (differences in tumor volumes, growth rates, apoptosis, proliferation indexes, and Bcl-2 and Bax protein levels) was used when the data were normally distributed with homogenous variance, and rank sum tests were used otherwise. Once significant differences were detected, Student-t tests were used for comparisons between two groups.ResultsOur results revealed that DOX diffused beyond the ablated tissue regions and entered tumor cells that were not affected by the HIFU ablation. Our results also show that HIFU in concert with DOX-loaded PLGA led to a significantly higher rate of tumor cell apoptosis and a lower rate of tumor cell proliferation in the areas beyond the HIFU-ablated tissues and consequently caused significant tumor volume shrinkage (tumor volumes:0.26±0.1,1.09±0.76, and 1.42±0.9cm3 for treatment, sham, and no treatment control, respectively).ConclusionsFrom these results, we concluded that the intralesional injection of DOX-loaded PLGA after HIFU ablation is significantly more effective than HIFU alone for the treatment of solid tumors. 相似文献
93.
红松阔叶林倒木贮量动态的研究 总被引:21,自引:1,他引:21
在森林倒木研究的基础上探讨长白山红松阔叶林倒木贮量的动态,涉及红松阔叶林倒木分解及其贮量的动态规律。研究表明,倒木分解,除心腐木外,均由表及里进行;倒木分解速率在其它生态条件相同时因树种、直径和部位而异。红松阔叶林倒木贮量动态包括现有倒木贮量和倒木年输入量两个分解动态过程,现有倒木贮量在头100年其干重迅速减少,其中椴树比红松尤速,前者分解91%,后者为72%.林地倒木贮量动态与倒木年输入量分解动态相似,但前者在分解初期贮量增加较大,因为部分现有倒木未完全分解;100年后趋于一致,并恒定于16~17t·hm-2,直至群落的顶极阶段结束. 相似文献
94.
禽致病性大肠杆菌毒力基因多重PCR方法的建立和应用 总被引:1,自引:0,他引:1
【目的】建立禽致病性大肠杆菌(Avian pathogenic Escherichia coli,APEC)黏附相关基因、侵袭及毒素相关基因、抗血清存活相关基因及铁转运相关基因的多重PCR方法,实现禽致病性大肠杆菌毒力基因的简便、快速检测。【方法】根据GenBank公布的基因序列,设计合成18对特异性引物,通过条件优化,建立四组多重PCR体系,并通过模板倍比稀释检测各组多重PCR的灵敏性。利用多重PCR检测100株APEC毒力基因的分布,验证多重PCR方法的可行性。【结果】根据PCR扩增片段大小判定,上述四组多重PCR体系均能同时扩增出该组中的各个毒力基因,且灵敏度分别为:103CFU、103CFU、105CFU、105CFU细菌和1ng、1ng、10ng、10ng DNA。100株APEC的毒力因子检测结果显示,多重PCR和单基因PCR结果一致。【结论】建立的四组多重PCR方法能够简便、快速地检测禽致病性大肠杆菌的毒力基因,可用于毒力基因的鉴定以及流行病学调查。 相似文献
95.
HSP90 mRNA在胃癌和大肠癌中表达的研究 总被引:1,自引:0,他引:1
目的为探讨胃癌和大肠癌细胞HSP90 mRNA表达的特点.方法利用核酸原位杂交技术,对79例胃肠癌组织进行检测.结果表明HSP90 mRNA在胃癌和大肠癌中的阳性率分别为55.56%(15/27)和69.23%(36/52).mRNA表达与病理类型、分化程度和有否淋巴结转移有相关性.结论 HSP90 mRNA在胃肠癌中有较高表达,检测HSP90 mRNA可以作为提示预后的重要临床指标. 相似文献
96.
Sun QiangLing Liu YinKun Lu WenJing Cheng Gang Zhou HaiJun Zhou XinWen Wei LiMing Dai Zhi Guo Kun Lu HaoJie 《中国科学C辑(英文版)》2007,50(3):403-411
In order to establish the novel high throughput, high efficiency and low cost technological platform for the research of N-glycoproteomics, to resolve the significance of characteristic expression profile of glycoprotein and to find the proteins
with biological functional importance, the glycoproteins with high-mannose core and the two antennary types were purified
and enriched by the Con A affinity chromatography. Con A affinity protein expression profiles of normal human liver tissue
were generated by using SDS-PAGE, two-dimensional electrophoresis (2-DE) followed by fast fluorescence staining based on multiplexed
proteomics (MP) technology. 301 visible protein spots on the gel were detected and 85 of glycoproteins were further successfully
identified via peptide mass fingerprinting (PMF) by a matrix assisted laser desorption/ionization time-of-flight mass spectrometry
(MALDI-TOF-MS/MS) and annotated to IPI databases. Identified glycoproteins definitely take part in the regulation of cell
cycle and metabolic processes. The glycosylation sites were predicted with NetNGlyc 1.0 and NetOGlyc 3.1 software, meanwhile
they were classified according to the geneontology methods. The construction of Con A affinity glycoprotein database of normal
human liver tissue would contribute to the subsequent research. 相似文献
97.
狭叶柴胡的抗过敏活性及其有效成分 总被引:4,自引:0,他引:4
本文以compound 48/80在体外诱导大鼠腹腔肥大细胞释放组胺,评价狭叶柴胡及其成分的抗过敏活性。狭叶柴胡醇提物及正丁醇部分(100μg/mL)、乙酸乙酯及水部分(10,100μg/mL)显著减少组胺释放,以乙酸乙酯部分的作用最强,狭叶柴胡挥发油(100μg/mL)对组胺释放呈现一定的促进作用。从乙酸乙酯部分分离得到异鼠李素和槲皮素两种主要化合物,均显著抑制组胺释放,表明黄酮为狭叶柴胡抗过敏作用的有效成分。 相似文献
98.
S. Wang F. Ding R. Zhao R. Li L. Zhang Y. Liu F. Gao L. Wang Y. Dai N. Li 《Theriogenology》2009,72(4):535-541
Introduction of selectable marker genes to transgenic animals could create an inconvenience to further research and may exaggerate public concerns regarding biological safety. The objective of the current study was to excise loxP flanked neoR in transgenic cloned cattle by transient expression of Cre recombinase. Green fluorescent protein gene (GFP) was incorporated to monitor Cre expression; therefore, Cre-expressed cells could be selected indirectly by fluorescence-activated cell sorting (FACS). The neoR was removed and Cre expressed transiently in GFP-positive colonies; excision of neoR was confirmed by single-blastocyst PCR in recloned blastocysts, with neoR-free fibroblast cells as donors. There was no difference (P > 0.05) in rates of cleavage (76.0% vs. 68.8%) or blastocyst formation (56.6% vs. 52.9%) between recloned embryos with neoR-free or neoR-included donors. The differential staining of recloned blastocysts were similar (P >0.05) in terms of total cell number (124 vs. 122) and the ratio of ICM (Inner Cell Mass) to the total cell number (38.1% vs. 38.2%). Furthermore, pregnancy and calving rates were not different (P > 0.05) from those of the control. In conclusion, we successfully excised neoR from transgenic cloned cattle; the manipulation did not affect the developmental competence of recloned preimplantation embryos. This approach should benefit bioreactor and transgenic research in livestock. 相似文献
99.
Dai RL Wang RX Jin JL Niu GN Lee JY Li SB Liu RZ 《Genetics and molecular research : GMR》2012,11(3):2422-2431
We investigated the frequency and types of Y-chromosome microdeletions and chromosomal anomalies in non-obstructive azoospermic and severely oligozoospermic infertile males in northeastern China. The sample consisted of 519 infertile males (456 azoospermic, 63 severely oligozoospermic). PCR assays for Y-chromosome microdeletions and chromosome analysis were performed on all patients and controls. Array-comparative genomic hybridization was performed for three patients with chromosomal anomalies. Fifty-nine of 519 patients (11.37%) had Y-chromosome microdeletions. Microdeletions were found in 11.18% (51/456) of the non-obstructive azoospermic patients and in 12.7% (8/63) of the severely oligozoospermic patients. Eleven of 51 non-obstructive azoospermic patients with Y-chromosome microdeletions had multiple segmental deletions in the AZFb+c regions; four of these patients had chromosomal anomalies. Our sample from northeastern China had a higher frequency of microdeletions among severely oligozoospermic than among non-obstructive azoospermic males. 相似文献
100.
Jie Dai Jun Zhou Hongmei Liu Kaixun Huang 《Journal of biological inorganic chemistry》2016,21(8):1037-1046
Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in d-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), β-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that d-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and β-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract. 相似文献