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991.
Xinpeng Yang Yue Feng Yang Li Dake Chen Xuanyan Xia Jialian Li Fenge Li 《Reproduction in domestic animals》2021,56(3):416-426
Sertoli cells are the only somatic cells in the seminiferous epithelium which directly contact with germ cells. Sertoli cells exhibit polarized alignment at the basal membrane of seminiferous tubules to maintain the microenvironment for growth and development of germ cells, and therefore play a crucial role in spermatogenesis. Androgens exert their action through androgen receptor (AR) and AR signalling in the testis is essential for maintenance of spermatogonial numbers, blood–testis barrier integrity, completion of meiosis, adhesion of spermatids and spermiation. In the present study, we demonstrated that AR gene could promote the proliferation of immature porcine Sertoli cells (ST cells) and the cell cycle procession, and accelerate the transition from G1 phase into S phase in ST cells. Meanwhile, miR-124a could affect the proliferation and cell cycle procession of ST cells by targeting 3′-UTR of AR gene. Furthermore, AR bound to the RNF4 via AR DNA-binding domain (DBD) and we verified that RNF4 was necessary for AR to regulate the growth of ST cells. Above all, this study suggests that AR regulates ST cell growth via binding to RNF4 and miR-124a, which may help us to further understand the function of AR in spermatogenesis. 相似文献
992.
CHEN Chun-yan JIA Ji-hui PAN Xiang-lin ZHANG Qi WANG Juan-dong ZHOU Ya-bin 《园艺学报》2004,20(7):1183-1186
AIM: To study the signal transduction pathway of apoptosis initiation induced by homoharringtonine in HL-60 cells. METHODS: After establishing the model of apoptosis initiation induced by homoharringtonine in HL-60 cells, at the point of apoptosis initiation, molecular caspase-3, Bcl-2, Bax and Fas/FasL were measured with flow cytometry and transmission electron microscope. ERK2 and P38 expression in HL-60 cells were detected by using immunohistochemistry. RESULTS: The model of apoptosis initiation induced by homoharringtonine was established in HL-60 cells. At the point of apoptosis initiation, upregulation of caspase-3 and decrease in Bcl-2/Bax were observed. However, the expression of Fas/FasL did not significantly change. ERK2 expression decreased and P38 expression increased. CONCLUSIONS: Caspase-3, Bcl-2, Bax and mitogen activated protein kinase pathways were involved in signal transduction of apoptosis initiation induced by homoharringtonine in HL-60 cells. 相似文献
993.
目的 为全面系统地了解古今中医文献中乳腺癌(乳岩)的用药规律,总结有效治疗措施指导临床实践。方法 将相关中医文献经过数据整理后建立乳腺癌文献信息标准数据库集,并在数据整理的基础上采用Clementine 12.0进行用药关联规则分析,得出古今中医文献中关于乳腺癌的用药规律,并运用SPSS 19.0进行文献中所用药物的使用频数/频率进行聚类分析。结果 治疗乳腺癌出现频次排名前五的药物类别由多到少依次为理气药 > 活血药 > 补阳药 > 滋阴药 > 化痰药。理气药常与活血药、补阳药、滋阴药、化痰药合用。结论 乳腺癌治疗以理气化瘀药为主,联合应用化痰药、补阳药、滋阴药的用药规律切合临床实际,值得推广应用。 相似文献
994.
AIM: To determine the effect of exogenous phosphocreatine (PCr) at different concentrations on transient outward potassium (Ito) current in rat ischemic ventricular mid-myocardial (M) cells and to explore the antiarrhythmia mechanism in the treatment of ischemic heart disease. METHODS: M cells were isolated enzymatically from left ventricular mid-myocardium of rats. Peak Ito current was recorded by patch-clamp technique in the whole-cell configuration when M cells were superfused with normal Tyrode solution, simple ischemic solution,and simulated ischemic solution containing PCr at concentrations of 5, 10, 20 and 30 mmol/L for 10 min. RESULTS: Peak Ito current density of M cells superfused with simple simulated ischemic solution was significantly reduced by (76.1?6.3)% (P<0.05) compared with M cells superfused with Tyrode solution. Ischemic solution containing 5, 10, 20 and 30 mmol/L PCr reduced peak Ito current density by (57.1?9.6)% (P<0.05), (40.3?10.3)% (P<0.05), (34.3?9.6)% (P<0.05) and (32.1?10.6)% (P<0.05),respectively. There was statistical difference among ischemic solution without PCr and containing PCr at concentrations of 5 and 10 mmol/L groups (P<0.05). No statistical difference among groups of 10, 20 and 30 mmol/L PCr was observed (P>0.05). CONCLUSION: PCr reverses the inhibition of Ito current under ischemic condition in M cells, which may be the mechanism responsible for arrhythmia prevention in ischemic heart disease. PCr at concentrations of 0~10 mmol/L exerts significant dose-effect relationship. 相似文献
995.
支持细胞对维持精子形成过程中的微环境起决定作用,它可以通过分泌功能、细胞间连接形成的血睾屏障功能以及吞噬功能等来促进精子的形成过程,其发育异常会导致不同程度的雄性生殖缺陷。基于支持细胞在雄性动物生殖过程中的作用,体外培养高纯度支持细胞可成为研究睾丸两大核心功能-精子发生和性激素分泌功能相关调节机制重要的细胞模型。此外,体外培养睾丸支持细胞也可作为生殖毒理学等新兴热点领域的细胞模型,为评估和研究环境因素对雄性生殖的影响提供便利。因此,作者系统地归纳、总结了目前关于动物支持细胞生物功能的研究及常用的体外分离纯化、培养及鉴定方法,以期为利用动物支持细胞开展雄性生殖领域的研究提供参考。 相似文献
996.
小麦白粉病是由小麦白粉菌(Erysiphe gramini f.sp.fritici)引起的真菌性病害。冬小麦品种复壮30中含有一个单隐性抗白粉病基因,即Pm5e。该基因对我国流行的白粉病小种表现为高抗或免疫。本研究以含抗白粉病基因的复壮30、感病品种Chancellor为材料构建F2分离群体,利用分离群体分组分析法(bulked segregant analysis,BSA)对该抗白粉病基因进行了SSR标记分析。在已定位在7B染色体上的56对SSR引物中,8对引物能在亲本间稳定的揭示多态性差异,3个引物Xwmc364、Xbarc065和Xwmc517在抗、感亲本,抗、感池间均表现多态性差异,F2分离群体的验证结果表明标记Xwmc364175、Xbarc06590和Xwmc517200与抗病基因连锁,遗传距离分别为4.9cM、5.1cM和18.5cM。其中标记Xwmc364175和Xbarc06590与抗病基因连锁紧密,在对Pm5e的标记辅助选择(marker-assisted selection,MAS)中具有重要利用价值。 相似文献
997.
《Communications in Soil Science and Plant Analysis》2012,43(6):707-716
Abstract Details and some evaluation are given of the use of a dialysis method for sampling pore water from depth in wetland substrata (peats), with particular reference to measurement of concentrations of ion species with stabilities dependent on redox potential. The method is based upon the burial and subsequent retrieval (after equilibration) of cells made from dialysis membrane filled with deionized water. Preliminary results of field investigations of concentrations of dissolved iron and sulphide in the pore water of base‐rich mires, as sampled by this method, are given. Results suggest that the method could have very considerable application and that its potential, and possible problems, deserve further examination. 相似文献
998.
Hajime NAGAHATA Mari KINE Hisato WATANABE Ai TANAKA Aoi TAKAHASHI Satoshi GONDAIRA Hidetoshi HIGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(12):1845
Intramammary infusion of Bifidobacterium breve (B. breve)-induced somatic cell (SC) counts, chemiluminescent response (CL), lactoferrin (LF) concentrations and mastitis-causing pathogens from quarters with subclinical mastitis were measured to evaluate innate immune response of mammary glands in dairy cows at 3 to 4 weeks before drying off. SC counts in 7 quarters of 7 control cows and 5 quarters of 6 cows with mastitis increased markedly on day 1 and SC values in control cows were significantly (P<0.05) increased and returned to pre-infusion levels on day 5 after B. breve-infusion. CL values in both groups increased markedly on day 1 and then decreased after B. breve-infusion; however, CL values in cows with mastitis did not return to normal levels on day 5 and at postpartum. The CL values were highly correlated with their SC counts in milk from both groups. LF concentrations increased toward day 3 after B. breve-infusion and were higher in cows with mastitis. B. breve-infusion eliminated 16.6% (1/6) of pathogens from 6 quarters with chronic subclinical mastitis. B. breve-induced SC responses in quarters from 3 cows with mastitis showed characteristic patterns of recovery, persistent and new infections. B. breve-induced SC counts in quarters from the cows in the pre-drying off were lower (25.7–70.6%) than those of the cows in mid-lactation. The intrinsic innate immune response in cows on pre-drying off may be decreased and appears to be insufficient to eliminate pathogens from mammary gland in the pre-drying off. 相似文献
999.
A three‐dimensional cell culture system as an in vitro canine mammary carcinoma model for the expression of connective tissue modulators 下载免费PDF全文
T. C. Cardoso S. S. Sakamoto D. Stockmann T. F. B. Souza H. L. Ferreira R. Gameiro F. V. Vieira M. J. Q. Louzada A. L. Andrade E. F. Flores 《Veterinary and comparative oncology》2017,15(2):582-593
In this study, derived complex carcinoma (CC) and simple carcinoma (SC) cell lines were established and cultured under two‐dimensional (2D) and three‐dimensional (3D) conditions. The 3D was performed in six‐well AlgiMatrix? (LifeTechnologies®, Carlsbad, CA, USA) scaffolds, resulting in spheroids sized 50–125 µm for CC and 175–200 µm for SC. Cell viability was demonstrated up to 14 days for both models. Epidermal growth factor receptor (EGFR) was expressed in CC and SC in both systems. However, higher mRNA and protein levels were observed in SC 2D and 3D systems when compared with CC (P < 0.005). The connective tissue modulators, metalloproteinases‐1, ‐2, ‐9 and ‐13 (MMPs), relaxin receptors 1 and 2 (RXR1 and RXR2) and E‐cadherin (CDH1) were quantitated. All were upregulated similarly when canine mammary tumour (CMT)‐derived cell lines were cultured under 3D AlgiMatrix, except CDH1 that was downregulated (P < 0.005). These results are promising towards the used of 3D system to increase a high throughput in vitro canine tumour model. 相似文献
1000.
A. Valencakova‐Agyagosova Z. Frischova Z. Sevcikova J. Hajurka J. Lepej I. Szakallova G. Kredatusova V. Nagy V. Ledecky 《Veterinary and comparative oncology》2014,12(3):205-214
The aim of this work was to determine levels of carcinoembryonic antigen (CEA) and cancer antigen (CA 15‐3) in the blood serum of 45 bitches. A modified procedure was used to determine the CEA and CA 15‐3 markers with the human kits using the radioimmunoassay method. Samples collected from extirpated tumour of mammary glands were histologically processed and classified as per WHO guidelines. The average age of animals with tumour was 10.00 ± 2.2 years; for healthy bitches average age was 4.2 ± 3.2 years. Values of CEA and CA 15‐3 were considered positive, if they exceeded 0.23 ng mL?1 and 7 IU mL?1, respectively. Average levels of CEA in the tumour group were 0.25 ± 0.06 versus 0.20 ± 0.03 in healthy bitches (P = 0.0001). The average CA 15‐3 value in bitches with tumour was 8.58 ± 1.27 versus 5.14 ± 1.34 in healthy animals (P < 0.0001). 相似文献