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91.
Localization of plasminogen activator and inhibitor, LH and androgen receptors and inhibin subunits in monkey epididymis 总被引:4,自引:1,他引:4
Epididymis is a site of sperm maturation and storage. Limited and
directed-proteolysis regulated by plasminogen activator (PA), plasminogen
activator inhibitor type-1 (PAI-1) and other related factors may play an
essential role in these processes. Our previous studies have demonstrated
that rat epididymis expressed luteinizing hormone receptor (LHR), tissue
type (t) and urokinase type (u)PA, mRNAs, and tPA activity was stimulated
in vitro by human chorionic gonoadotrophin (HCG). In the present study we
further examined localization of mRNAs for tPA, uPA, LHR, androgen receptor
(AR), as well as inhibin subunits alpha, betaA and betaB in rhesus monkey
epididymis. Using in-situ hybridization with digoxygenin-labelled cRNA
probes, we have demonstrated that tPA and PAI-1 mRNAs were localized in
epithelial cells of adult monkey epididymis. uPA mRNA was localized in the
same areas, but to a much smaller extent. tPA, uPA and PAI-1 mRNAs were
greatly expressed in the caput and corpus of adult epididymis than in other
regions. In-vitro experiments showed that both tPA and uPA activities in
epididymal cells were dramatically stimulated by HCG, but not by follicle
stimulating hormone (FSH). LHR (but not FSH receptor) and AR mRNAs were
localized in the epithelial cells of the epididymis. However, LHR mRNA was
detected in both adult and immature infant monkeys, whereas AR was found
only in the adult. Inhibin alpha, betaA and betaB mRNAs were also detected
in this organ, betaA mRNA being more strongly expressed in the caput than
in other regions of the epididymis. We suggest that LH and androgen may be
the key hormones in coordination with the PA-PAI-1 system in regulating
epididymal differentiation and sperm maturation.
相似文献
92.
多种金属离子与单宁酸反应媒染微血管的对比研究 总被引:2,自引:0,他引:2
目的 镜下观察单宁酸与金属盐溶液中Ca2 + 、Au+ 、Ag+ 、Pb2 + 、Cu2 + 、Al3 + 、U6+ 、K+ 联用显示大脑微血管的效果。方法 用单宁酸媒染固定液灌流大鼠 ,取脑切片 ,入氯化钙、氯化金、硝酸银、硝酸铅、硫酸铜、硫酸铝钾、醋酸双氧铀、高锰酸钾和重铬酸钾等溶液中呈色。结果 单宁酸与Ca2 + 、Cu2 + 、Ag+ 、Al3 + 结合显示血管清晰 ,与Au+ 、U6+ 、Pb2 + 、K+ 联用媒染血管效果欠佳。结论 含Ca2 + 、Cu2 + 、Ag+ 、Al3 + 的金属盐类可替代氯化铁媒染微血管 ,氯化金、醋酸双氧铀、硝酸铅、重铬酸钾和高锰酸钾不宜与单宁酸联用来显示血管 相似文献
93.
94.
Mengshu Zhang Likui Lu Bin Wei Yingying Zhang Xiang Li Yajun Shi Wei Ge Miao Sun 《American journal of medical genetics. Part A》2020,182(10):2432-2436
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes. 相似文献
95.
目的比较传统有支架心包瓣与CS无支架心包二尖瓣的性能。方法测试瓣膜分为两组:A组,有支架心包瓣(与Ionescu-Shiley瓣相似);B组,无支架心包二尖瓣(与Quattro相似,由中南大学研制,简称CS瓣)。检测内容包括:①钙化倾向(SD鼠皮下埋藏模型);②组织学;③热皱缩温度;④断裂强度;⑤生物相容性;⑥血流动力学;⑦疲劳试验;⑧有限元分析。结果①B组钙化明显低于A组(P<0.01)。②组织学示A组心包片有大块钙化及胶元纤维裂解;B组仅见稍许钙化灶,胶原纤维保存完好。③热皱缩温度A组与B组无统计学意义。④断裂强度B组明显强于A组(P<0.005)。⑤内皮细胞种植后第1天,A组细胞明显少于B组(P<0.001);第3天A组已无细胞生长,B组内皮细胞增殖活跃;多数细胞Ⅷ因子检测呈阳性。⑥在模拟心输出量为2、4、6L,A组跨瓣压差明显高于B组(P<0.05),返流量和回流百分比A组显著高于B组(P<0.01),有效瓣口面积两组无统计学意义,仅在流量为4L时A组优于B组。⑦B组寿命比A组(n=2)长2.5倍。⑧B组瓣叶应力分布较为合理。结论CS无支架心包二尖瓣避免了应力集中区,其抗钙化、胶原纤维保存、断裂强度、生物相容性、血流动力学、疲劳寿命等均明显优于传统有支架心包瓣。 相似文献
96.
Kobayashi M Hirano A Kumano T Xiang SL Mihara K Haseda Y Matsui O Shimizu H Yamamoto K 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(4):291-303
The Rad17-replication factor C (Rad17-RFC) and Rad9-Rad1-Hus1 complexes are thought to function in the early phase of cell-cycle checkpoint control as sensors for genome damage and genome replication errors. However, genetic analysis of the functions of these complexes in vertebrates is complicated by the lethality of these gene disruptions in embryonic mouse cells. We disrupted the Rad17 and Rad9 loci by gene targeting in the chicken B lymphocyte line DT40. Rad17-/- and Rad9-/- DT40 cells are viable, and are highly sensitive to UV irradiation, alkylating agents, and DNA replication inhibitors, such as hydroxyurea. We further found that Rad17-/- and Rad9-/- but not ATM-/- cells are defective in S-phase DNA damage checkpoint controls and in the cellular response to stalled DNA replication. These results indicate a critical role for chicken Rad17 and Rad9 in the cellular response to stalled DNA replication and DNA damage. 相似文献
97.
Annette J Schlueter Arthur M Krieg Peter De Vries Xiang Li 《Journal of interferon & cytokine research》2002,22(7):799-806
Interferon-alpha (IFN-alpha) is the primary regulator of transient Ly-6C expression on T cells. B cells, which do not express Ly-6C in the resting state, have been reported to express Ly-6C following exposure to proinflammatory stimuli. This study examined the factors controlling Ly-6C expression on B cells and the kinetics of Ly-6C expression in the presence of these factors. In vivo studies demonstrated that proinflammatory (Th1) cytokines transiently upregulate B cell Ly-6C expression. In vitro studies identified Th1 cytokines, particularly IFN-alpha and IFN-gamma, as the principal cytokines responsible for this induction. Polyclonal B cell activators (anti-IgM and recombinant CD40 ligand trimer) showed minimal ability to independently induce Ly-6C expression on B cells but did enhance the ability of IFNs to induce expression. Th2 cytokine environments did not result in B cell Ly-6C expression, and interleukin-4 (IL-4) actually antagonized the IFN-driven induction of Ly-6C. Ly6.1 strains of mice consistently demonstrated a greater ability to express Ly-6C on B cells than did Ly-6.2 strains. Together, these studies demonstrate the ability of Th1 but not Th2 cytokine environments to transiently induce the expression of Ly-6C on B cells and provide additional evidence for differences in the regulation of Ly-6C expression in Ly6.1 and Ly6.2 strains. 相似文献
98.
内隐记忆的研究证据及临床意义 总被引:5,自引:0,他引:5
内隐记忆 (implicitmemory)一词最初由Graf与Schacter于 1985年提出 ,指对特定的过去经验进行有意识或外显的回忆测验中表现出来的对先前获得信息的无意识提取 ,也就是说 ,在有意或无意间获得的信息、技能或习惯 ,虽不能有意识地回忆和再认 ,但会影响类似作业的成效和行为的有效性。这一概念的提出扩大了记忆研究的内涵 ,因此迅速成为记忆研究的热点之一。目前内隐记忆的研究在测量方法与理论解释方面都取得了一些进展 ,大量证据表明它与外显记忆存在质的不同 ,是一个相对独立的记忆系统。不过现存的问题也很多 ,… 相似文献
99.
100.
复杂手术常需多科医生协商制定综合性治疗方案,网络协同三维可视化软件可使方案制定直观而精确。我们采用VTK工具包对DICOM格式CT图像数据进行三维重建并作网格简化,将结果所得多边形网格模型无缝集成到用HOOPS/3DAF所开发的图形系统进行显示,并用HOOPS/Stream工具包转成适合网络传输的HSF无损压缩流文件,再用HOOPS/NET工具包实现基于Client/Server架构的协同三维交互可视化系统。所得三维重建结果清晰,协同三维可视化操作实时度高。本研究实现了一个协同手术仿真开发平台,该架构易于进一步添加模拟手术操作与修复体设计功能。 相似文献