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Science China(Life Sciences) 2006年第1期49卷 37-45页

作者： CHEN Xinlei GAO Hongjuan GAO Fei WEI Peng HU Zhaoyuan liu yixun State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100080China

The corpus luteum(CL)is a transient endocrine organ that secretes progesterone to support early *** implantation is unsuccessful,luteolysis is *** tissue re-modeling occurs during CL formation and *** this study,we have studied the possible in-volvement of MMP-2,-9,-14,and their inhibitors,TIMP-1,-2,-3 in the CL of cycling rhesus monkey at various stages by in situ hybridization,immunohistochemistry and microscopic *** re-sults showed that the MMP-2 mRNA and protein were mainly expressed in the endothelial cells at the early and middle stages of the CL development,while their expressions were observed in the luteal cells at the late stage during luteal ***-9 protein was detected in the CL at the early and middle stages,and obviously increased at the late *** expressions of MMP-14 and TIMP-1 mRNA were high at the early and late stages,and low at the middle ***-2 mRNA was high throughout all the stages,the highest level could be observed at the late *** TIMP-3 produc-tion was detected throughout all the stages,but obviously declined during CL ***-9,-14 and TIMP-1,-2,-3 were mainly localized in the cytoplasm of the steroidogenic *** results suggest that the MMP/TIMP system is involved in regulation of CL development in the primate,and the coordinated expression of MMP-2,-14 and TIMP-1,-3 may have a potential role in the CL forma-tion and the functional maintaining,while the interaction of MMP-2,-9,-14 and TIMP-1,-2,-3 might also play a role in CL regression at the late stage of CL development in the primate.

关键词： MMP TIMP corpus luteum rhesus monkey

Expression and regulation of orphan receptor TR2 mRNA in germ cells of cryptorchid testis in rat and rhesus monkey

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Chinese Science Bulletin 2000年第8期45卷 720-725页

作者： GUO Caixia HU Zhaoyuan ZOU Rujin MU Xiaomin liu yixun State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100080China Kunming Institute of Zoology Chinese Academy of Sciences.Kunming 650223China

Expression and cellular localization of orphan receptor TR2 mRNA in relation to germ cell apoptosis in cryptorchid testes of rat and rhesus monkey have been studied by using in situ hybridization and in situ 3’-end labeling of DNA fragments (T躈EL). The results show that: (i) TR2 mRNA is specifically expressed in the germ cells, mainly in the spermatocytes, round and elongated spermatids. The expression level of TR2 mRNA varies with the seminiferous cycle. (ii) in the rat cryptorchid testes on days 3 and 5 after the surgery, the germ cells began to undergo apoptosis with no evident decrease in TR2 mRNA level. On day 7.5, however, most germ cells underwent apoptosis, while the expression level of TR2 mRNA declined markedly, and TR2 mRNA was rarely expressed on day 10 thereafter. (iii) On days 15 and 20 of the cryptorchid testes of rhesus monkey, TR2 mRNA was only expressed in a few of primary spermatocytes and the mRNA was almost undetectable on days 30, 45, 60. These results suggest that TR2 mRNA

关键词： orphan receptor TR2 in situ hybridization cryptorchidism spermatogenesis apoptosis.

Endometrium implantation and ectopic pregnancy

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Science China(Life Sciences) 2004年第4期47卷 293-302页

作者： liu yixun State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100080China

Embryo in uterine implantation is a complex and multifactor-related process and is a downstream and ideal point for woman fertility control. Understanding the cellular and molecular mechanism of implantation is a prerequisite for development of anti-implantation contraceptives. In spite of considerable accumulation of information from the laboratory animals that has been achieved, it is difficult to generate such information in human due to ethical restriction and experimental limitation, and the present knowledge for understanding the definitive mechanisms which control these events remains elusive. Embryo implantation can also occur outside uterus. Some women with abdominal pregnancies could successfully complete the processes of gestation and bear normal babies, implying that implantation itself may be not an endometrium-specific process. Reproductive biologists should cooperate with gynecologists to further comparatively study the molecular and cellular mechanisms of implantation normally occurring in endometrium and abnormally appearing outside uterine cavity. Such collaborative studies may generate new important information for developing anti-implantation contraceptive and for techniques of accurate diagnosis of ectopic pregnancy. A specially designed GnRH-2 analog and a combination use of low dose RU486 and gossypol as anti-implantation contraceptives have been suggested. Keywords embryo implantation - implantation window - materno-embryonic dialogue - ectopic pregnancy

关键词： embryo implantation,implantation window,materno-embryonic dialogue,ectopic pregnancy.

Over-expression of Toll-like receptor 2 up-regulates heme oxygenase-1 expression and decreases oxidative injury in dairy goats

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Journal of Animal Science and Biotechnology 2017年第2期8卷 351-360页

作者： Shoulong Deng Kun Yu Wuqi Jiang Yan Li Sutian Wang Zhuo Deng Yuchang Yao Baolu Zhang Guoshi liu yixun liu Zhengxing Lian State Key Laboratory of Stem Cell and Reproductive Biology Institute of Zoology Chinese Academy of SciencesBeijing 100101 China Laboratory ofAnimal Genetics and Breeding College of Animal Science and TechnologyChina Agricultural University Beijing 100193 People's Republic of China National key Lab of Agrobiotechnology College of Biological SciencesChina Agricultural University Beijing 100193 People's Republic of China. Department of Animal Science Oklahoma State University Stillwater OK74078 USA College of Animal Science and Technology Northeast Agricultural University Harbin 150030 People's Republic of China State Oceanic Administration Beijing 100860 People's Republic of China

Background： Mastitis, an infection caused by Gram-positive bacteria, produces udder inflammation and oxidative injury in milk-producing mammals. Toll-like receptor 2（TLR2） is important for host recognition of invading Grampositive microbes. Over-expression of TLR2 in transgenic dairy goats is a useful model for studying various aspects of infection with Gram-positive bacteria, in ***： We over-expressed TLR2 in transgenic dairy goats. Pam3CSK4, a component of Gram-positive bacteria,triggered the TLR2 signal pathway by stimulating the monocytes-macrophages from the TLR2-positive transgenic goats, and induced over-expression of activator protein-1（AP-1）, phosphatidylinositol 3-kinase（PI3K） and transcription factor nuclear factor kappa B（NF-κB） and inflammation factors downstream of the signal ***： Compared with wild-type controls, measurements of various oxidative stress-related molecules showed that TLR2, when over-expressed in transgenic goat monocytes-macrophages, resulted in weak lipid damage, high level expression of anti-oxidative stress proteins, and significantly increased m RNA levels of transcription factor NF-E2-related factor-2（Nrf2） and the downstream gene, heme oxygenase-1（HO-1）. When Pam3CSK4 was used to stimulate ear tissue in vivo the HO-1 protein of the transgenic goats had a relatively high expression ***： The results indicate that the oxidative injury in goats over-expressing TLR2 was reduced following Pam3CSK4 stimulation. The underlying mechanism for this reduction was increased expression of the anti-oxidation gene HO-1 by activation of the Nrf2 signal pathway.

关键词： Haem oxygenase Nrf2 signal pathway Toll-like receptor 2 Transgenic goats

Follicular growth,differentiation and atresia

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Chinese Science Bulletin 2003年第17期48卷 1786-1790页

作者： JIN Xuan & liu yixun State Key Laboratory of Reproductive Biololgy, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China State Key Laboratory of Reproductive Biololgy Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Only limited numbers of primordial follicles in mammalian ovary grow and differentiate to reach the stage of dominate follicles and ovulate. 99% of the follicles in the ovary undergo atresia at various stages of development. Regulation of follicular growth, development and atresia is a complex process and involves interactions between endocrine factors and intraovarian regulators. This review summa-rized:ⅰ) FSH may not be a survival factor in regulating slow-growing preantral follicles. Some locally produced growth factors, activin and orphan receptors might play a more important role at this stage. ⅱ) Estrogen, activin/ inhibin and follistatin coordinate with FSH to regulate and control follicle differentiation. ⅲ) There are two types of follicular atresia induced by apoptosis which originates from GC or oocyte, respectively. Early translation of tPA mRNA into tPA protein in oocyte may be associated with oocyte apoptosis.

关键词：哺乳动物原始卵泡卵泡生长粒状细胞细胞分化

Molecular basis of cryptorchidism-induced infertility

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Science China(Life Sciences) 2010年第11期53卷 1274-1283页

作者： liu yixun & LI XiXia State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

Artificial cryptorchidism or local testicular heat treatment can induce reversible oligospermia or azoospermia in monkeys and rats via germ cell apoptosis. Local warming of monkey testes in water at 43°C for 2 consecutive days (30 min per day) decreased the number of sperm in the semen by up to 80% on d 28, and the effect was completely reversed on d 144. Germ cells rely heavily on Sertoli cells for structural and nutritional support. Specialized junctions that play a pivotal role in spermatogenesis occur at sites of Sertoli-Sertoli and Sertoli-germ cell contact in the seminiferous epithelium. We demonstrated that expression of tight junction (TJ)-associated molecules, such as occludin and zonula occludens-1 (ZO-1), were greatly reduced 24–48 h after heat treatment, while the permeability of the blood-testis barrier (BTB) was simultaneously increased, but recovered 10 d later. These results indicate a reversible disruption of the BTB associated with transient inductions of transforming growth factor (TGF) β2 and β3 expression, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase activation, and concomitant loss of occludin and ZO-1. This suggests that expression of TJ-associated molecules and the BTB was reversibly perturbed by mild testicular hyperthermia, and that the heat-induced induction of TGF-β might be involved in downregulating TJ-associated proteins, leading to cell junction reduction. This review discusses the changes in total gene expression patterns after experimental cryptorchidism in adult mouse testes, and the cloning of several novel, physiologically significant spermatogenesis-specific genes.

关键词： cryptorchidism spermatogenesis apoptosis heat stress Sertoli cells blood-testis barrier tight junction

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前沿法网格划分方法在脑组织变形中的应用

解剖学杂志 2008年第3期31卷 391-393页

作者：曹杰刘翌勋复旦大学数字医学研究中心上海200032

目的:拟开发一种全自动网格划分技术,生成脑组织的网格模型,用于模拟脑组织的变形。方法:用本研究提出的前沿法网格划分方法,对临床实际病例的脑组织三维图像进行网格划分。结果:本研究算法生成的脑组织大部分网格的α值处于[0.8,1]范... 详细信息

目的:拟开发一种全自动网格划分技术,生成脑组织的网格模型,用于模拟脑组织的变形。方法:用本研究提出的前沿法网格划分方法,对临床实际病例的脑组织三维图像进行网格划分。结果:本研究算法生成的脑组织大部分网格的α值处于[0.8,1]范围内。结论:该方法得到的脑组织网格对后期的脑组织变形校正的精度相比其他方法有显著提高,提高了神经外科手术导航的精度。

关键词：前沿法网格划分脑组织变形

基于边界分析的重载轮胎滚动过程接地角和印记非对称性分析与验证

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汽车工程 2022年第1期44卷 73-81页

作者：刘志浩刘钇汛高钦和刘秀钰火箭军工程大学兵器科学与技术国家重点学科实验室西安710025

基于解析弹性基础的柔性胎体模型,并考虑胎体圆环的径向变形与切向变形之间的耦合关系,为重载大扁平比轮胎建立了柔性环二维轮胎低频动力学模型。采用接地边界求解方法探究了轮胎的接地滚动过程中的接地角和接地印记的非对称特性,并进... 详细信息

基于解析弹性基础的柔性胎体模型,并考虑胎体圆环的径向变形与切向变形之间的耦合关系,为重载大扁平比轮胎建立了柔性环二维轮胎低频动力学模型。采用接地边界求解方法探究了轮胎的接地滚动过程中的接地角和接地印记的非对称特性,并进行了轮胎接地刚度和接地印记非线性实验验证。结果表明:采用接地边界求解可准确计算接地角和接地印记;基于胎内应变传感器的接地印记估计方法可间接测量轮胎滚动过程中的接地印记。

关键词：重载子午胎轮胎动力学基于弹性基础的柔性胎体模型接地边界求解法

STUDIES ON THE GENE EXPRESSION OF TISSUE-TYPE PLASMINOGEN *** ACTIVATOR INHIBITOR TYPE-1,ANDROGEN RECEPTOR AND INHIBINα IN TESTIS,EPIDIDYMIS,DEFERNT DUCT,SEMINAL VESICLE AND PROSTATE OF RAT AND MONKEY:LOCALIZATION AND HORMONAL REGULATION

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STUDIES ON THE GENE EXPRESSION OF TISSUE-TYPE PLASMINOGEN **...

第二次北京生育调节国际学术研讨会

作者： Hongming Zhou yixun liu Inst.Zool Chinese Acad.Sci.Beijing 100080 PR China

＜正＞In our previous studies we have demonstrated that isolated Sertoli cells from mouse,rat and monkey are capable of simutaneously secreting tissue-type plasminogen activator（tPA） and plasminogen activator inhibitor type-1（PAI-1）,both of which are hormonally *** studies indicated that tPA and PAI-1 localized in the Sertoli cells,spermatocytes,spermatids and the residual

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基于周向应变分析的重载轮胎垂向力估计算法

上海交通大学学报 2023年第10期57卷 1273-1281页

作者：刘钇汛刘志浩高钦和黄通马栋火箭军工程大学导弹学院西安710025

为实现对轮胎垂向力的量化估计,开展了基于周向胎内应变分析的重载轮胎垂向力估计算法研究.建立16.00R20重载轮胎有限元模型,通过轮胎加载实验和模态振动实验对比发现模型垂向刚度误差和振动频率误差分别在7.79%和5.49%以内,验证了模型... 详细信息

为实现对轮胎垂向力的量化估计,开展了基于周向胎内应变分析的重载轮胎垂向力估计算法研究.建立16.00R20重载轮胎有限元模型,通过轮胎加载实验和模态振动实验对比发现模型垂向刚度误差和振动频率误差分别在7.79%和5.49%以内,验证了模型的有效性;利用有限元方法研究了垂向力对轮胎接地特性和内衬层周向应变的影响规律,根据周向应变曲线特征分析了周向应变与接地角的关系,提出并验证了轮胎接地角表征指标,3个表征指标误差均小于8%;以接地角和接地长度作为辨识特征,结合灰狼优化算法和支持向量回归机建立垂向力估计模型,通过有限元仿真对比验证估计精度.结果表明:结合应变曲线零阶、一阶、二阶导数特征点间距角的表征指标能较准确估算接地角;基于灰狼支持向量回归机的垂向力估计算法估计效果良好,估计值与有限元仿真值误差在1.8%以内,能够准确地估算轮胎垂向力.

关键词：有限元模型周向应变垂向力支持向量回归机