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MRI在睾丸生殖细胞肿瘤中的诊断价值
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作者 林亚南 程敬亮 张勇 《中国CT和MRI杂志》 2025年第2期159-160,共2页
目的 研究不同病理类型的睾丸生殖细胞肿瘤在磁共振中的表现,进一步提高MRI对该病的诊断价值。方法 回顾性分析13例经病理证实的睾丸生殖细胞肿瘤患者的临床资料及MRI表现。结果 13例睾丸生殖细胞瘤中,3例精原细胞瘤,T1WI均呈等信号,T2W... 目的 研究不同病理类型的睾丸生殖细胞肿瘤在磁共振中的表现,进一步提高MRI对该病的诊断价值。方法 回顾性分析13例经病理证实的睾丸生殖细胞肿瘤患者的临床资料及MRI表现。结果 13例睾丸生殖细胞瘤中,3例精原细胞瘤,T1WI均呈等信号,T2WI呈稍高信号,增强呈轻度强化;1例胚胎性癌,T1WI呈低信号,T2WI呈稍高信号,增强呈明显不均匀强化;1例卵黄囊瘤,T1WI及T2WI呈高低信号,增强呈明显不均匀强化;8例混合型生殖细胞瘤,其中T1WI呈高低信号7例,呈低信号1例,T2WI呈高低信号6例,呈高信号2例,增强呈明显不均匀强化。结论 睾丸生殖细胞肿瘤病理类型不同MRI表现不尽相同,MRI对睾丸生殖细胞肿瘤的诊断价值较高。 展开更多
关键词 生殖细胞肿瘤 病理类型 磁共振
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认知错误是如何发生的?——《枪炮、病菌与钢铁》研究人类发明案例的启示
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作者 石硕 《云南师范大学学报(哲学社会科学版)》 北大核心 2025年第1期12-16,共5页
人类文明的演进,与发明密切相关。对于发明,传统看法是人们的需要促成了发明的产生,换言之,“需要乃发明之母”。这一观点看去天经地义,似无问题。但贾雷德·戴蒙德(Jared Diamond)在《枪炮、病菌与钢铁》一书中,通过对众多发明案... 人类文明的演进,与发明密切相关。对于发明,传统看法是人们的需要促成了发明的产生,换言之,“需要乃发明之母”。这一观点看去天经地义,似无问题。但贾雷德·戴蒙德(Jared Diamond)在《枪炮、病菌与钢铁》一书中,通过对众多发明案例的系统梳理与分析,却得出两个完全不同的认识:一,在众多发明案例中,因需要而产生的发明只占极少一部分,绝大部分发明并非因需要而产生,相反,而是发明催生了需要,即“发明常常是需要之母,而不是相反”。二,将发明归咎于某一天才人物即“英雄史观”往往是后世的杜撰,发明“不是靠孤立的英雄行为”,而是技术长期积累、发展的结果。 展开更多
关键词 发明之母 需要之母 戴蒙德 《枪炮、病菌与钢铁》
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鱼类性别可塑性的分子机制
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作者 戴生飞 孙丽娜 +2 位作者 周林燕 王德寿 李明辉 《中山大学学报(自然科学版)(中英文)》 CAS 北大核心 2025年第1期133-146,共14页
鱼类性别具有高度的可塑性,具体表现为天然性逆转、原发性逆转和次发性逆转。近年来,一系列研究都证明鱼类性别可塑性与雌激素密切相关。一旦阻断性腺雌激素的合成,无论是未分化还是已分化卵巢都将性逆转为精巢。鱼类的性别决定通路基... 鱼类性别具有高度的可塑性,具体表现为天然性逆转、原发性逆转和次发性逆转。近年来,一系列研究都证明鱼类性别可塑性与雌激素密切相关。一旦阻断性腺雌激素的合成,无论是未分化还是已分化卵巢都将性逆转为精巢。鱼类的性别决定通路基因缺失诱导的性逆转也与雌激素相关。重要的是,发现生殖细胞的可塑性依赖于foxl3和dmrt1的同时存在,缺失其中一个都不能通过改变雌激素水平从而诱导性逆转。因此,foxl3和dmrt1是生殖细胞响应雌激素的关键基因。另外,表观遗传调控基因kdm6bb通过选择性剪接介导温度诱导的性逆转。这些研究增进了我们对鱼类性别可塑性分子机制的认识。 展开更多
关键词 雌激素 性别可塑性 生殖细胞 体细胞 鱼类
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热风及微波组合热风干燥对小麦胚芽品质的影响
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作者 钟杨 张歌兴 +6 位作者 张方芹 林舒婷 王梅 张新振 孙玥 梁进 李雪玲 《中国调味品》 北大核心 2025年第1期21-27,共7页
为了保持小麦胚芽原有的营养价值并提升其贮藏品质,该研究主要探究了两种干燥方式(热风干燥、微波组合热风干燥)对小麦胚芽品质的影响。采用化学方法比较了干燥后两种小麦胚芽的水分活度(Aw)、脂肪酸值、游离氨基酸含量、卵磷脂含量、... 为了保持小麦胚芽原有的营养价值并提升其贮藏品质,该研究主要探究了两种干燥方式(热风干燥、微波组合热风干燥)对小麦胚芽品质的影响。采用化学方法比较了干燥后两种小麦胚芽的水分活度(Aw)、脂肪酸值、游离氨基酸含量、卵磷脂含量、脂肪酶活性、色度、酸价、TBA值等指标。结果表明,120℃热风干燥60 min的小麦胚芽的水分活度(Aw)、脂肪酸值、游离氨基酸含量、卵磷脂含量、脂肪酶活性、色度L^(*)值分别为0.29、3.42 mg KOH/g、66.41μg/g dw、69.41 mg/g、29.81 mg/g、56.22;700 W微波80 s后再120℃热风干燥30 min的小麦胚芽对应的指标分别为0.08、4.33 mg KOH/g、94.26μg/g dw、13.15 mg/g、31.09 mg/g、36.88。贮藏实验表明,两种干燥处理均能显著降低小麦胚芽的水分含量和水分活度,微波组合热风干燥可更好地抑制小麦胚芽的脂肪酸败。 展开更多
关键词 小麦胚芽 热风干燥 微波干燥 理化品质 贮藏
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基因编辑鸡制备方法及应用
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作者 吴可欣 谷钰洲 +2 位作者 孙从佼 杨宁 邵丽娃 《中国家禽》 北大核心 2025年第2期143-150,共8页
鸡是研究发育生物学、免疫学以及传染病学的优良模型,同时是满足人们对肉、蛋需求的重要农业经济动物。近年来,随着全球鸡肉产量与消耗量的不断增长,养禽业对禽病防控、保种育种的需求也随之增加。为此,研究人员结合基因编辑技术制备了... 鸡是研究发育生物学、免疫学以及传染病学的优良模型,同时是满足人们对肉、蛋需求的重要农业经济动物。近年来,随着全球鸡肉产量与消耗量的不断增长,养禽业对禽病防控、保种育种的需求也随之增加。为此,研究人员结合基因编辑技术制备了转基因鸡或基因编辑鸡,从而更加深入地了解鸡生长发育、免疫抗病机制,为产业实践提供了坚实的理论基础。由于鸡独特的生殖生理特点,无法获取单细胞卵子,难以应用哺乳动物的基因编辑方法。文章综述了现有制备基因编辑鸡的方法及优缺点,并指出了基因编辑鸡制备过程存在的问题,为基因编辑鸡的制备提供参考。 展开更多
关键词 基因编辑鸡 原始生殖细胞 生物反应器 PGC基因编辑
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羟基脲对大鼠Sertoli-germ细胞共培养的影响 被引量:1
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作者 周莉 吴纯启 +2 位作者 杨保华 荆淑芳 廖明阳 《中国临床药理学与治疗学》 CAS CSCD 2008年第5期512-516,共5页
目的:观察羟基脲(Hydroxyurea,HU)对雄性大鼠Sertoli-germ细胞共培养的细胞毒性作用。方法:在Sertoli-germ细胞共培养模型中分别加入不同浓度HU(0、10-3、10-2、10-1mol/L)后,孵育96h;以及加入10-2mol/LHU后分别孵育24、48、72、96h。结... 目的:观察羟基脲(Hydroxyurea,HU)对雄性大鼠Sertoli-germ细胞共培养的细胞毒性作用。方法:在Sertoli-germ细胞共培养模型中分别加入不同浓度HU(0、10-3、10-2、10-1mol/L)后,孵育96h;以及加入10-2mol/LHU后分别孵育24、48、72、96h。结果:在各给药组,96h时HU导致germ细胞从Sertoli细胞层的脱落增加,呈现量效关系。在10-3mol/L以上浓度组,细胞活性逐渐下降,细胞脱落增加。同样,随着给药时间的增加,germ细胞脱落率和乳酸脱氢酶(LDH)的漏出逐渐增加,细胞活性逐渐下降。结论:HU对雄性大鼠睾丸Sertoli-germ细胞共培养模型的germ细胞具有明显毒性作用。 展开更多
关键词 羟基脲 Sertoli-germ细胞 共同培养技术 细胞毒性
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用均匀设计方法优化Sertoli-germ细胞培养条件的研究 被引量:2
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作者 黄厚今 王瑞淑 +1 位作者 徐维光 杨青 《中国公共卫生学报》 1999年第2期10-12,共3页
采用均匀设计方法对Sertoligerm细胞共培养条件进行优化。结果显示,所观察的三个因素(3或6个水平)中,培养温度和pH值对生精细胞脱落的影响最为明显,而小牛血清浓度的影响较少。回归方程提示该培养系统的适宜条件... 采用均匀设计方法对Sertoligerm细胞共培养条件进行优化。结果显示,所观察的三个因素(3或6个水平)中,培养温度和pH值对生精细胞脱落的影响最为明显,而小牛血清浓度的影响较少。回归方程提示该培养系统的适宜条件,逐步回归分析剔除了小牛血清浓度的因素,说明不必加入过多小牛血清。此外,用所获回归方程对指标值进行回算,结果提示,以脱落生精细胞数作为培养效果的观察指标比较稳定。 展开更多
关键词 均匀设计 Sertoli-germ细胞共培养 大鼠
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使用Glo Germ开展生物安全教育初探 被引量:2
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作者 潘欣 蔡家麟 +2 位作者 李晗 陈龙 吴鉴今 《西北医学教育》 2011年第5期999-1001,共3页
为提高生物技术专业本科学员生物安全基本技能,在教学过程中引入Glo Germ作为可视化教学工具,直观生动地让学员在设定的实验场景中了解模拟"病菌"的传播过程,学习污染控制技术。该举措通过师生的互动,提高了本科生的生物安全... 为提高生物技术专业本科学员生物安全基本技能,在教学过程中引入Glo Germ作为可视化教学工具,直观生动地让学员在设定的实验场景中了解模拟"病菌"的传播过程,学习污染控制技术。该举措通过师生的互动,提高了本科生的生物安全意识。 展开更多
关键词 生物技术专业 Glo germ 模拟病菌 生物安全教育
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不同预处理辅助水酶法提取玉米胚芽油的实验研究
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作者 张雅娜 沙莎 +3 位作者 马丽媛 李佳 刘俊廷 佟禹凝 《发酵科技通讯》 2025年第1期42-47,共6页
为了提高玉米胚芽油的提取率,采用冷冻-微波解冻和乙醇冷浴辅助水酶法提取玉米胚芽油,通过正交实验优化冷冻-微波解冻预处理条件和乙醇冷浴预处理条件。实验结果表明:优化冷冻-微波解冻预处理条件,包括冷冻温度、冷冻时间、粉碎时间和... 为了提高玉米胚芽油的提取率,采用冷冻-微波解冻和乙醇冷浴辅助水酶法提取玉米胚芽油,通过正交实验优化冷冻-微波解冻预处理条件和乙醇冷浴预处理条件。实验结果表明:优化冷冻-微波解冻预处理条件,包括冷冻温度、冷冻时间、粉碎时间和微波解冻时间,得出玉米胚芽油提取率为69.22%;优化乙醇冷浴预处理条件,包括冷浴时间、冷浴温度、乙醇质量分数和m(玉米胚芽)∶V(乙醇),得出玉米胚芽油提取率为58.27%。 展开更多
关键词 玉米胚芽油 水酶法 乙醇冷浴 冷冻-微波解冻
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免疫检查点抑制剂在复发及难治性性腺恶性生殖细胞肿瘤中的研究进展
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作者 张天宇 杨佳欣 《中国医学科学院学报》 北大核心 2025年第1期131-136,共6页
生殖细胞肿瘤常发生于性腺部位,恶性程度高、病情进展快。由于对化疗高度敏感,生殖细胞肿瘤治愈率较高,但仍有部分患者因化疗耐药和疾病进展而死亡。免疫检查点抑制剂的使用显著改善了多种实体肿瘤的预后,但在生殖细胞肿瘤中的免疫机制... 生殖细胞肿瘤常发生于性腺部位,恶性程度高、病情进展快。由于对化疗高度敏感,生殖细胞肿瘤治愈率较高,但仍有部分患者因化疗耐药和疾病进展而死亡。免疫检查点抑制剂的使用显著改善了多种实体肿瘤的预后,但在生殖细胞肿瘤中的免疫机制和免疫治疗尚未得到充分研究,复发及难治性生殖细胞肿瘤是否能获益于免疫检查点抑制剂仍需进一步评估。本文通过总结生殖细胞肿瘤中免疫相关机制、免疫治疗病例报道及临床试验结果,评估免疫治疗疗效,为未来的基础研究和临床实践提供参考。 展开更多
关键词 恶性生殖细胞肿瘤 肿瘤微环境 免疫检查点抑制剂 临床试验
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CRISPR/Cas9系统在家畜生殖细胞中的研究进展
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作者 解雅茹 金昊延 +2 位作者 孔辰 蔡蓓 张令锴 《畜牧兽医学报》 北大核心 2025年第2期479-491,共13页
生殖细胞是生命体遗传物质传递的主要载体,在家畜育种过程中发挥重要作用。人们对畜产品需求的不断增加促进了精确育种技术的发展。基因编辑技术显著提升基因强化和疾病治疗成效,这一进展凸显了将该技术应用于家畜生殖细胞研究的重要性... 生殖细胞是生命体遗传物质传递的主要载体,在家畜育种过程中发挥重要作用。人们对畜产品需求的不断增加促进了精确育种技术的发展。基因编辑技术显著提升基因强化和疾病治疗成效,这一进展凸显了将该技术应用于家畜生殖细胞研究的重要性。与其他基因编辑技术相比,CRISPR/Cas9系统和CRISPR/Cas12系统的研究较为深入。CRISPR/Cas技术已在多项研究中取得突破性进展,被视为一种极有潜力的育种改良手段。本文主要针对两种CRISPR/Cas系统及CRISPR/Cas9系统在家畜生殖细胞中的应用进行综述,对家畜生殖细胞形成过程进行简要概括,阐述CRISPR/Cas9系统和CRISPR/Cas12系统的原理、构成和衍生技术,介绍CRISPR/Cas9系统在家畜生殖细胞中的应用,对基因编辑技术广泛应用于家畜生殖细胞进行展望,旨在为未来畜牧基因编辑领域的研究提供参考。 展开更多
关键词 基因编辑技术 CRISPR/Cas9系统 CRISPR/Cas12系统 家畜生殖细胞
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Cloning and Expression of BTB/POZ-Domain from Zebrafish gcl (Germ Cell-Less), and Appraisement of Its Polyclonal-Antibody
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作者 DENG Fengjiao CHENG Pengxiang +2 位作者 LAN Qiang XU Yan ZHUANG Tiangang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期123-128,共6页
In this study, a recombinant pET28c-gBTB/POZ was constructed by cloning the sequence of the BTB/POZ domain of the zebrafish gcl (germ cell-less) into the expression vector pET28c, and pET28c-gBTB/POZ was transformed... In this study, a recombinant pET28c-gBTB/POZ was constructed by cloning the sequence of the BTB/POZ domain of the zebrafish gcl (germ cell-less) into the expression vector pET28c, and pET28c-gBTB/POZ was transformed into BL21(DE3) pLysS strain to express the fusion protein for the preparation of antibody. Polyclonal-antibody against the GCL-BTB/POZ domain was prepared by immunizing rabbit with the fusion protein, and the Western Blot and immuno-histochemical analysis were performed to detect the quantity of the polyclonal-antibody. The result indicates that the polyclonal-antibodies were of good quantity and specification. Further studies will be performed to demonstrate the function and expression pattern of the GCL protein during the development process of zebrafish with the polyclonal-antibody. 展开更多
关键词 gel (germ cell-less) polycolonal-antibody BTB/ POZ domain zebrafish (Danio rerio)
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苏云金芽孢杆菌芽孢萌发相关基因gerM的克隆及功能研究 被引量:1
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作者 严晓华 刘钢 谭华荣 《微生物学报》 CAS CSCD 北大核心 2007年第1期17-21,共5页
依照蜡状芽孢杆菌gerM基因的保守序列设计引物,从苏云金芽孢杆菌中扩增出640bp的DNA片段。以此为探针,从苏云金芽孢杆菌部分基因组酶切文库中成功地克隆到了一个4·5kb的DNA片段。序列分析表明,该片段包含一个完整的开放阅读框,其... 依照蜡状芽孢杆菌gerM基因的保守序列设计引物,从苏云金芽孢杆菌中扩增出640bp的DNA片段。以此为探针,从苏云金芽孢杆菌部分基因组酶切文库中成功地克隆到了一个4·5kb的DNA片段。序列分析表明,该片段包含一个完整的开放阅读框,其预测的编码产物与枯草芽孢杆菌GerM蛋白具有很高的同源性,将该基因命名为gerM。RT-PCR分析表明,gerM基因仅在芽孢形成的过程中表达。通过同源重组的策略构建了gerM基因的阻断突变株。研究表明,gerM基因的破坏影响苏云金芽孢杆菌芽孢萌发的速率和比例。 展开更多
关键词 苏云金芽孢杆菌 部分基因组酶切文库 germ基因 RT-PCR 芽孢萌发
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Germ cell apoptosis induced by Ureaplasma urealyticum infection 被引量:27
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作者 Chen XU Mei-Ge LU +2 位作者 Jing-Sheng FENG Qang-Su Guo Y-Fei WANG Department of Histology & Embryology, Shanghai Second Medical University, Shanghai 200025, China 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第3期199-204,共6页
Aim: To study the effect of Ureaplasma urealyticum (UU) infection on germ cell apoptosis of male rats. Meth-ods: Male rats were infected artificially with UU serotype 8 (T_(960)). Morphological changes of germ cells i... Aim: To study the effect of Ureaplasma urealyticum (UU) infection on germ cell apoptosis of male rats. Meth-ods: Male rats were infected artificially with UU serotype 8 (T_(960)). Morphological changes of germ cells in the sem-iniferous tubules and the lumen of the epididymides were observed under the light microscope. Fluorescence-conjugatedpolyclonal antibodies to Fas and Fas ligand (FasL) were used to localize Fas and FasL. TUNEL staining of germ cellsand Sertoli cells was performed by the AKPase method. TUNEL-positive rate (% positive cells) and TUNEL-positivearea (area occupied by stained cells) were analysed by KS400 Image Analysis System. The DNA laddering analysiswas performed by agarose gels electrophoresis. Results: In those rats infected with UU; (1) Exfoliated germ cellswere dramatically increased. Many multinucleated giant cells were found in the seminiferous tubules and the lumen ofthe epididymides. (2) The number of TUNEL-positive cells and the TUNEL-positive area were significantly increased.(3) The expression of Fas and FasL in germ cells and Sertoli cells was up-regulated. (4) Discrete bands of fragmentedDNA were found in the testicular cells. Conclusion: In male rats, germ cell apoptosis was increased in UU infec-tion . (Asian J Androl 2001 Sep; 3: 199 - 204) 展开更多
关键词 germ cells APOPTOSIS Ureaplasma urealyticum FAS/FASL DNA electrophoresis
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Assessment of germ cell apoptosis in cryptorchid rats 被引量:12
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作者 IzzetKoak MehmetDündar +1 位作者 Mine Hekimgil Pinar Okyay 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第3期183-186,共4页
Aim: To investigate the relationship between germ cell degeneration and apoptosis in cryptorchid rats. Methods: Thirteen 21-day-old Wistar rats were made unilaterally cryptorchid by closing the left inguinal canal. At... Aim: To investigate the relationship between germ cell degeneration and apoptosis in cryptorchid rats. Methods: Thirteen 21-day-old Wistar rats were made unilaterally cryptorchid by closing the left inguinal canal. At day 30 (Group 1, n=6) and day 60 (Group 2, n=7) after operation, the testes were removed for histopathological examination. The controls (n=8) were sham operated and were sacrificed at day 60. Germ cell apoptosis was assessed by means of the TUNEL method. Results: Spermatogenesis was arrested and the testicular and seminiferous tubular diameters were significantly reduced In the unilateral undescended testes (UUTs) compared with the contralateral descended testes (CDTs) and the control rats. However, atrophic changes, pathological calcification, necrosis of seminiferous tubule, and absence or sloughing of germ cells were not found in all the animals. The spermatocytes were the main type of germ cells undergoing apoptosis in all the groups. In the UUTs, there was a significant and time-dependent increase in the mean apoptotic index. By 60 days after surgery, increased apoptosis in germ cells was also observed in the CDTs. Conclusion: Apoptosis is the predominant mechanism of germ cell death rather than atrophy and necrosis in cryptorchidism. 展开更多
关键词 CRYPTORCHIDISM germ cells APOPTOSIS TUNEL method
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Effect of prolonged cryptorchidism on germ cell apoptosisand testicular sperm count 被引量:7
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作者 Albaha Barqawi Herald Trummer Randall Meacham 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第1期47-51,共5页
Aim: To evaluate the long term effect of experimental cryptorchidism on germ cell apoptotic rate and testicular sperm content in adult rats. Methods: Bilateral cryptorchidism was created in 40 adult male Sprague-Dawle... Aim: To evaluate the long term effect of experimental cryptorchidism on germ cell apoptotic rate and testicular sperm content in adult rats. Methods: Bilateral cryptorchidism was created in 40 adult male Sprague-Dawley rats by surgically manipulating the testes into the abdominal cavity and closing the internal inguinal ring. The rats were sacrificed and the testes removed 6 hours and 2, 4, 7, 21, 28 and 56 days after cryptorchidism. Germ cell apoptosis was quantified by means of TUNEL assay and apoptosis was confirmed using transmission electron microscopy. Results: The rate of apoptosis peaked at 4 days of cryptorchidism and then progressively declined to a nadir at 14 days of cryptorchidism. At 56 days of cryptorchidism, the germinal epithelium was largely depleted by the apoptotic process and only a few mature sperm were seen within the testis. At this point, a few tubules were seen to be repopulating with primary spermatocytes and the level of germ cell apoptosis began to increase marginally. Testicular sperm count (TSC) began to decline rapidly at day 7 of cryptorchidism. Only a few mature sperm were found in the testes of rats following 56 days of cryptorchidism. Multinucleated giant cells (MGC) were most numerous within the seminiferous tubules at day 4. At day 7, 35 % of MGCs were TUNEL positive. At all subsequent time points, however, MGCs fail to stain positive for apoptosis. This resumption of increased apoptosis coincided with the appearance of a population of primary spermatocytes in some seminiferous tubules. Moreover, there was not a corresponding increase in the number of mature sperm after 56 days of cryptorchidism. Conclusion: The decline in germ cell apoptosis after 4 days of cryptorchidism can be attributed to be the result of an overall depletion of germ cells. It appears that after a prolonged cryptorchidism (56 days), there is a limited resumption of spermatogenesis presumably as a result of a decrease in the maturing germ cells undergoing programmed cell death. 展开更多
关键词 CRYPTORCHIDISM APOPTOSIS germ cell TESTIS
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Expression of germ cell nuclear factor in mouse germ cells and sperm during postnatal period 被引量:11
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作者 ChenXu Zong-YaoZhou +1 位作者 Qiang-SuGuo Yi-FeiWang 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第3期217-222,共6页
Aim: To assess the spatial and temporal expression of germ cell nuclear factor (GCNF) in male mouse germ cells during postnatal development and in sperm before and after capacitation. Methods: The indirect immun-ofluo... Aim: To assess the spatial and temporal expression of germ cell nuclear factor (GCNF) in male mouse germ cells during postnatal development and in sperm before and after capacitation. Methods: The indirect immun-ofluorescence method with anti-GCNF antiserum was used to investigate the GCNF expression in mice at day 8, 10, 14, 17, 20, 28, 35, 70, and 420 after birth and in sperm before and after capacitation. Results: With the proceeding of spermatogenesis, GCNF was first detected in the nuclei of spermatogonia and a few early stage primary sperma-tocytes at day 8, which was increased gradually at day 10 to 14 inclusive. From day 17 to day 20, the GCNF was concentrated in round spermatids, while both spermatogonia and early stage primary spermatocytes became GCNF negative. From day 28 until day 420, strong GCNF expression was shown in round spermatids and pachytene spermatocytes, while spermatogonia, early primary spermatocytes and elongating spermatids were all GCNF negative. In addition, it was also found that GCNF was localized on the acrosomal cap region of spermatozoa and there was a big change in GCNF expression during capacitation, from 98 % GCNF positive before capacitation to about 20 % positive following capacitation. The localization of GCNF in caput and cauda spermatozoa was similar. Conclusion: GCNF may play important roles in spermatogenesis, capacitation and fertilization. 展开更多
关键词 germ cell nuclear factor SPERM spatial expression temporal expression MOUSE
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Generation of male germ cells from induced pluripotent stem cells (iPS cells): an in vitro and in vivo study 被引量:13
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作者 Yong Zhu Hong-Liang Hu +10 位作者 Peng Li Shi Yang Wei Zhang Hui Ding Ru-Hui Tian Ye Ning Ling-Ling Zhang Xi-Zhi Guo Zhan-Ping Shi Zheng Li Zuping He 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第4期574-579,共6页
Recent studies have reported that induced pluripotent stem (iPS) cells from mice and humans can differentiate into primordial germ cells. However, whether iPS cells are capable of producing male germ cells is not kn... Recent studies have reported that induced pluripotent stem (iPS) cells from mice and humans can differentiate into primordial germ cells. However, whether iPS cells are capable of producing male germ cells is not known. The objective of this study was to investigate the differentiation potential of mouse iPS cells into spermatogonial stem cells and late-stage male germ cells. We used an approach that combines in vitrodifferentiation and in vivotransplantation. Embryoid bodies (EBs) were obtained from iPS cells using leukaemia inhibitor factor (LIF)-free medium. Quantitative PCR revealed a decrease in Oct4 expression and an increase in StraSand Vasa mRNA in the EBs derived from iPS cells, iPS cell-derived EBs were induced by retinoic acid to differentiate into spermatogonial stem cells (SSCs), as evidenced by their expression of VASA, as well as CDH1 and GFRal, which are markers of SSCs. Furthermore, these germ cells derived from iPS cells were transplanted into recipient testes of mice that had been pre-treated with busulfan. Notably, iPS cell-derived SSCs were able to differentiate into male germ cells ranging from spermatogonia to round spermatids, as shown by VASA and SCP3 expression. This study demonstrates that iPS cells have the potential to differentiate into late-stage male germ cells. The derivation of male germ cells from iPS cells has potential applications in the treatment of male infertility and provides a model for uncovering the molecular mechanisms underlying male germ cell development. 展开更多
关键词 DIFFERENTIATION induced pluripotent stem cells male germ cells retinoic acid TRANSPLANTATION
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Optimal dose of busulfan for depleting testicular germ cells of recipient mice before spermatogonial transplantation 被引量:6
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作者 De-Zhi Wang Xin-Hua Zhou +1 位作者 Yu-Lin Yuan Xin-Min Zheng 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第2期263-270,共8页
Successful spermatogonial transplantation requires depletion of the host germ cells to allow efficient colonization of the donor spermatogonial stem cells. Although a sterilizing drug,busulfan (Myleran),is commonly ... Successful spermatogonial transplantation requires depletion of the host germ cells to allow efficient colonization of the donor spermatogonial stem cells. Although a sterilizing drug,busulfan (Myleran),is commonly used for preparing a recipient mouse before transplantation,the optimal dose of this drug has not yet been defined.The present study investigated the effects of different doses of busulfan (10-50 mg per kg body weight) on survival rate,testicular mass and histomorphology,and on the haploid spermatids and spermatozoa of male BALB/c mice.The results suggest that a dosage of 30 mg kg^-1 is optimal for the ablative treatment withbusulfan used to prepare the recipient mice. This dose results in an adequate depletion of the host germ cells for colonization of donorderived spermatogonial stem cells and causes the lowest death rate of the animals. 展开更多
关键词 BUSULFAN germ cells infertility MICE myleran spermatogonial transplantation TESTIS
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Wheat Germ: An Overview on Nutritional Value, Antioxidant Potential and Antibacterial Characteristics 被引量:8
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作者 Awad A. Mahmoud Adel A. A. Mohdaly Nady A. A. Elneairy 《Food and Nutrition Sciences》 2015年第2期265-277,共13页
Wheat germ is a by-product derived from the wheat milling industry. Defatted wheat germ is the main by-product of the wheat germ in the oil extraction process. This study aims at development of efficient and low cost ... Wheat germ is a by-product derived from the wheat milling industry. Defatted wheat germ is the main by-product of the wheat germ in the oil extraction process. This study aims at development of efficient and low cost processing methods to transform these residues in added value co-product. In this study, wheat germ was analysed for its proximate composition, fatty acid composition, physical and chemical characteristics of wheat germ oil. The basic chemical composition analyses revealed high values of dry matter (87.37 g/100g FW), significant amounts of total protein and fat (27.69 and 8.99 g/100g FW, respectively) content and low ash content (3.08 g/100g FW). The quality of the extracted oils was assessed in terms of acid value, iodine value, saponification value, peroxide value, refractive index, and unsaponifiable matter. The fatty acid profile was found to be made up of linoleic followed by palmitic and oleic as the major fatty acids. Antioxidant properties and in vitro antibacterial activity of defatted wheat germ (DWG) extract were also determined. DWG, as a source of natural antioxidants and antibacterial, could be used to formulate nutraceuticals with potential applications to reduce the level of oxidative stress. The antioxidant potency of the DWG extracts could be the basis for its health promoting potential. The results showed that these by-products could be used as a source of bioactive compounds beneficial for health. 展开更多
关键词 ANTIBACTERIAL Activity ANTIOXIDANT Properties Defatted WHEAT germ FATTY ACID WHEAT germ Oil
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