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71.
72.
为评估定量荧光PCR(QF-PCR)方法在男性不育遗传学诊断中的应用价值,文章对78例非梗阻性男性不育患者,采用精液常规检测精子情况,并检测患者性激素水平;采用QF-PCR方法对患者性染色体多态性STR位点及特异性位点进行检测;采用常规染色体G显带方法进行核型分析;PCR检测AZF微缺失。结果显示78例非梗阻性男性不育患者中发现无精子症患者18例,少精子症患者20例,总检出率为48.72%。采用QF-PCR方法检出3例47,XXY患者,2例46,XX(SRY+)性反转患者,1例AZFc区微缺失患者,与细胞培养染色体分析和AZF微缺失PCR检测结果相符。与传统方法相比,QF-PCR技术能更迅速、直接、可靠地检测到男性不育患者的染色体异常区域,及早发现染色体细微结构异常,有助于染色体异常造成的男性不育症的鉴别诊断。 相似文献
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A tissue-engineered mesh fabricated with adipose-derived mesenchymal stem cells (AD-MSCs) cultured on a silk fibroin scaffold is evaluated for use in female pelvic reconstruction. Thirty-five female Sprague Dawley rats were divided into four groups. Group A (n?=?10) were implanted with polypropylene meshes, Group B (n?=?10) with silk fibroin scaffolds and Group C (n?=?10) with tissue-engineered meshes. Group D (n?=?5) acted as the tissue control. The tissue-engineered mesh was produced as follows. AD-MSCs were obtained from adipose tissue of rats designated to Group C. The cells were seeded onto a silk fibroin scaffold, cultured and then observed by scanning electron microscopy (SEM). Histological studies of these meshes were performed at 4 and 12 weeks after implantation and mechanical testing was carried out on all groups before implantation and at 12 weeks after implantation. AD-MSCs displayed fibroblast-like shapes and were able to differentiate into adipocytes or fibroblasts. SEM observation showed that AD-MSCs proliferated and secreted a matrix onto the silk fibroin scaffolds. After implantation of the scaffolds into rats, histological analysis revealed better organized newly formed tissue in Group C than in controls. Group C also had a similar failure force (2.67?±?0.15 vs 2.33?±?0.38 N) and a higher Young’s modulus (2.99?±?0.19 vs 1.68?±?0.20 MPa) than a normal vaginal wall, indicating the potential of this tissue-engineered approach. AD-MSCs were validated as seed cells for tissue engineering. The silk fibroin scaffold thus shows promise for application with AD-MSCs in the fabrication of tissue-engineered mesh with good biocompatibility and appropriate mechanical properties for pelvic floor reconstruction. 相似文献
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为探究黑线仓鼠(Cricetulus barabensis)繁殖功能与促肾上腺皮质激素释放激素(CRH)基因结构的关系,参考近缘种的cDNA序列设计引物,采用RT-PCR法克隆得到了黑线仓鼠CRH基因的部分序列,克隆得到长度为1 112bp,为外显子1和外显子2的部分序列,包括全部编码区序列564 bp;编码区共编码187个氨基酸,GenBank登录号为JQ416143.利用编码区序列构建系统进化树,结果显示,黑线仓鼠与大鼠、小鼠亲缘关系最近,与其他哺乳动物亲缘关系较近,而与原鸡亲缘关系最远,此结果与物种的进化关系相一致.同时对其编码的蛋白质进行一级结构分析及二级、三级结构预测,得到了CRH的信号肽序列和41个氨基酸组成.本研究首次报道了黑线仓鼠的CRH基因序列,为进一步探究CRH基因奠定基础,对系统分析CRH的功能具有重要的参考价值,同时该cDNA序列可作为物种亲缘关系或遗传距离研究的理想标记. 相似文献
77.
Qi Ye Ming Yan Lin Xu Hou Cao Zhenjiang Li Yong Chen Shuya Li Hanjie Ying 《Biotechnology letters》2009,31(4):537-542
An NADPH-dependent carbonyl reductase (PsCR) gene from Pichia stipitis was cloned. It contains an open reading frame of 849 bp encoding 283 amino acids whose sequence had less than 60% identity
to known reductases that produce ethyl (S)-4-chloro-3-hydroxybutanoates (S-CHBE). When expressed in Escherichia coli, the recombinant PsCR exhibited an activity of 27 U/mg using ethyl 4-chloro-3-oxobutanoate (COBE) as a substrate. Reduction
of COBE to (S)-CHBE by transformants in an aqueous mono-phase system for 18 h, gave a molar yield of 94% and an optical purity of the (S)-isomer of more than 99% enantiomeric excess. 相似文献
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79.
SuiKang Wang YouHuang Bai ChenJia Shen YunRong Wu SaiNa Zhang DeAn Jiang Tom J. Guilfoyle Ming Chen YanHua Qi 《Functional & integrative genomics》2010,10(4):533-546
Sorghum, a C4 model plant, has been studied to develop an understanding of the molecular mechanism of resistance to stress.
The auxin-response genes, auxin/indole-3-acetic acid (Aux/IAA), auxin-response factor (ARF), Gretchen Hagen3 (GH3), small
auxin-up RNAs, and lateral organ boundaries (LBD), are involved in growth/development and stress/defense responses in Arabidopsis and rice, but they have not been studied in sorghum. In the present paper, the chromosome distribution, gene duplication,
promoters, intron/exon, and phylogenic relationships of Aux/IAA, ARF, GH3, and LBD genes in sorghum are presented. Furthermore,
real-time PCR analysis demonstrated these genes are differently expressed in leaf/root of sorghum and indicated the expression
profile of these gene families under IAA, brassinosteroid (BR), salt, and drought treatments. The SbGH3 and SbLBD genes, expressed
in low level under natural condition, were highly induced by salt and drought stress consistent with their products being
involved in both abiotic stresses. Three genes, SbIAA1, SbGH3-13, and SbLBD32, were highly induced under all the four treatments,
IAA, BR, salt, and drought. The analysis provided new evidence for role of auxin in stress response, implied there are cross
talk between auxin, BR and abiotic stress signaling pathways. 相似文献
80.
利用液体发酵、木屑固体发酵和米饭固体发酵3种方式培养鲍姆纤孔菌(桑黄)菌丝体,对菌丝体醇提物的体外抗氧化、抗肿瘤和抗衰老生物活性进行了研究。结果表明,木屑固体发酵、液体发酵和米饭固体发酵的菌丝体醇提物清除H2O2自由基的IC50值分别为78.28±0.32、27.73±0.57和7.84±0.37;米饭培养的桑黄菌丝体醇提物在低浓度500μg/mL下对超氧阴离子自由基清除作用到达80%,在相同的浓度下对DPPH自由基清除率也明显高于其他两种方法,表现出较高的抗氧化活性。木屑以及米饭培养方法得到的菌丝体对PC12神经细胞损伤修复均有较好的效果,液体培养的桑黄菌丝体表现的修复作用较低;液体发酵培养的菌丝体醇提物浓度在100μg/mL时,对肿瘤细胞HepG2的抑制率达70%,高于其他两种培养方法的抑制作用。 相似文献