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Ventricular Septal Crypts:Remnants of Spontaneous Interventricular Defect Closure?
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作者 Alberto Cresti Stefania Sparla +2 位作者 Stefania Stefanelli Andrea Picchi Ugo Limbruno 《Congenital Heart Disease》 SCIE 2023年第1期1-6,共6页
Background:Ventricular crypts are quite a common finding during cardiac imaging,but their etiology is unclear.A possible final result of a spontaneous ventricular septal defect closure has been supposed but never inve... Background:Ventricular crypts are quite a common finding during cardiac imaging,but their etiology is unclear.A possible final result of a spontaneous ventricular septal defect closure has been supposed but never investigated in earlier studies.Method:From January 1997 to December 2020,all newborns diagnosed to have a ventricular septal defect were prospectively entered in our database and those with an isolated defect were included in the study.Ventricular septal defects were classified into four types:perimembranous,trabecular muscular,inlet and outlet.A long-term follow up was performed in order to visualize the possible residual formation of a septal myocardial crypt.Results:A total of 376 isolated ventricular septal defects(314 muscular and 54 perimembranous,4 inlet,4 outlet)were detected.Follow up ranged from 1 to 23 years and showed that,among muscular type,a spontaneous closure occurred in 284(91%),26 did not close(8,28%),2 required surgical intervention(0,63%),3 were lost at follow up(0,95%).During this period,after spontaneous defect closure closure,20 crypts were found(6,4%).Conclusion:This study shows that a muscular ventricular septal defect may evolve in the 6.4%of cases in a residual septal crypt.Although septal crypts occur more frequently in patients affected by hypertrophic and hypertensive cardiomyopathy,they may also represent the evolution of a spontaneous closure of a muscular interventricular defect. 展开更多
关键词 Ventricular crypts ventricular septal defect cardiac imaging
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一株鸡源唾液乳杆菌的分离鉴定及其对育雏早期蛋鸡肠道健康的影响
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作者 于秀菊 胡燕姣 +7 位作者 刘佳悦 王海东 朱芷葳 范阔海 王蓉蓉 段承昊 石佳炜 杨丽华 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第9期4161-4171,共11页
旨在从健康海兰褐鸡肠道中分离鉴定乳酸菌,并研究其对育雏早期蛋鸡肠道健康的影响。本研究采用细菌培养技术、16S rRNA测序和牛津杯扩散法,分离、筛选、鉴定可产细菌素的乳酸菌菌株,检测其对高温、pH和胆盐的耐受性;动物试验选取240只1... 旨在从健康海兰褐鸡肠道中分离鉴定乳酸菌,并研究其对育雏早期蛋鸡肠道健康的影响。本研究采用细菌培养技术、16S rRNA测序和牛津杯扩散法,分离、筛选、鉴定可产细菌素的乳酸菌菌株,检测其对高温、pH和胆盐的耐受性;动物试验选取240只1日龄健康、体重相近的海兰褐鸡,随机分为4组,每组60只鸡,包括对照组(C)、低剂量唾液乳杆菌CL09组(L)、中剂量唾液乳杆菌CL09组(M)和高剂量唾液乳杆菌CL09组(H),研究该乳酸菌菌株对育雏早期蛋鸡生长性能、免疫器官指数及肠道健康相关指标的影响。试验周期为21 d。结果表明:分离菌为可产细菌素的革兰阳性菌,结合16S rRNA鉴定结果将其命名为唾液乳杆菌CL09,该菌的无细胞上清液可抑制大肠杆菌、沙门菌、金黄色葡萄球菌和李斯特菌的生长。该菌的耐受温度为60℃,具有耐酸、耐胆盐的特性。动物试验结果显示:与对照组相比,灌服唾液乳杆菌CL09可以增加雏鸡体重和免疫器官重量;H组十二指肠、空肠的隐窝深度变化最为显著,L和M组十二指肠绒毛高度显著增加,且H组十二指肠绒毛呈“波浪形”;M和H组肠道干细胞标记基因Lgr 5和Bmi1表达水平升高极显著(P<0.001);H组的黏膜屏障基因Zo-1和Ocln的mRNA表达水平升高极显著(P<0.01);M组潘氏细胞标记性基因Lyz的mRNA表达水平最高。L、M和H组的杯状细胞标记基因Muc的mRNA表达水平均升高,且差异极显著(P<0.01)。综上所述,源自健康海兰褐鸡肠道的唾液乳杆菌CL09,通过促进雏鸡肠道干细胞分化为潘氏细胞和杯状细胞,增加绒毛高度,降低隐窝深度,从而增大肠道的黏膜面积。该菌具有调节育雏早期鸡肠道健康的良好特性,可作为益生菌的备选菌株。 展开更多
关键词 蛋鸡 唾液乳杆菌 肠道健康 绒毛高度 隐窝深度
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从“玄府-隐窝”视域辨治溃疡性结肠炎肠屏障受损
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作者 程媛 寇富舜 +2 位作者 李军祥 陶伟伟 刘丽娜 《中国中医药信息杂志》 CAS CSCD 2024年第6期167-170,共4页
“玄府”作为中医藏象理论的微观结构遍布于人体各部,急性溃疡性结肠炎微观病变表现为结肠隐窝脓肿甚至结构紊乱。其湿热蕴结大肠,肠道因实而闭的发病特点与“玄府”贵开忌阖、贵通忌闭的理念契合。肠道隐窝机械屏障与黏液屏障功能与“... “玄府”作为中医藏象理论的微观结构遍布于人体各部,急性溃疡性结肠炎微观病变表现为结肠隐窝脓肿甚至结构紊乱。其湿热蕴结大肠,肠道因实而闭的发病特点与“玄府”贵开忌阖、贵通忌闭的理念契合。肠道隐窝机械屏障与黏液屏障功能与“玄府”推陈出新、气液宣通的特点有共通之处,可为肠“玄府”理论提供形态学依据。清开玄府法能够抑制湿热郁腐之物蕴结、肠道郁闭不通导致的肠“玄府闭阖”状态,推动“玄府-隐窝”学说在治疗溃疡性结肠炎早期隐窝病变的指导作用和理论支撑。 展开更多
关键词 溃疡性结肠炎 肠屏障 玄府 隐窝 清开玄府法
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小鼠小肠类器官炎症模型的构建
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作者 陈浩 李蕊 +5 位作者 易菲 周丽 陈嘉琪 朱璠 管城艳 吴娜 《天津医药》 CAS 2024年第1期16-21,共6页
目的建立体外小肠类器官培养体系,探讨脂多糖(LPS)对小肠类器官生长和炎性因子分泌的影响。方法体外无菌分离并收集C57BL/6小鼠小肠隐窝细胞团,使用类器官基质胶进行包埋,并在完全培养基的支撑下,培养形成具有小肠上皮样结构的立体多叶... 目的建立体外小肠类器官培养体系,探讨脂多糖(LPS)对小肠类器官生长和炎性因子分泌的影响。方法体外无菌分离并收集C57BL/6小鼠小肠隐窝细胞团,使用类器官基质胶进行包埋,并在完全培养基的支撑下,培养形成具有小肠上皮样结构的立体多叶结构的小肠类器官。小肠类器官培养5~7 d或类器官中央区域变黑时传代,传代后3 d将小肠类器官随机分为不同质量浓度LPS组(0、150、175、200、225、250、275、300 mg/L)。在LPS诱导24 h和48 h后观察小肠类器官生长和形态特征变化;用CCK-8法检测不同时间和质量浓度LPS对小肠类器官诱导炎症后增殖活力的影响;采用酶联免疫吸附试验检测4种不同质量浓度LPS(0、175、200、225 mg/L)在不同时间对类器官培养上清液中粒细胞-巨噬细胞集落刺激因子(GM-CSF)、白细胞介素(IL)-1α、IL-6、IL-10水平的影响。结果初步构建了小鼠小肠类器官培养体系。不同时间和质量浓度LPS作用小肠类器官诱导炎症后,通过形态学观察到小肠类器官会有不同程度的膨胀和内腔凋亡现象的发生,受损的肠上皮中隐窝或肠干细胞的增殖分化和出芽数量也受到不同程度的抑制。小肠类器官在175~225 mg/L的LPS诱导24 h和48 h后,其增殖活力呈现不同程度的降低(P<0.05),但细胞活力仍大于50%。200 mg/L和225 mg/L的LPS诱导24 h和48 h后,IL-1α、IL-6和GM-CSF水平部分升高(P<0.05);200 mg/L的LPS诱导24 h和48 h后,IL-10水平降低(P<0.05)。结论本研究初步构建了不同质量浓度和时间的LPS诱导小肠类器官体外肠道炎症损伤模型,为今后肠道疾病的机制研究和有效药物的筛选提供了更为可靠的研究平台。 展开更多
关键词 小肠 类器官 脂多糖类 生物因子 隐窝
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鼻内镜下泪前隐窝入路术式及柯陆入路术式治疗对上颌窦内翻性乳头状瘤患者机体应激指标的影响与安全性研究
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作者 刘景林 黄员福 薛梅 《中外医疗》 2024年第15期13-16,共4页
目的 探讨鼻内镜下泪前隐窝入路术式及柯陆入路术式治疗对上颌窦内翻性乳头状瘤(Inverting Papilloma, IP)患者机体应激指标的影响与安全性。方法 前瞻性随机选取2019年4月—2023年8月三明市第二医院确诊为上颌窦IP的120例患者为研究对... 目的 探讨鼻内镜下泪前隐窝入路术式及柯陆入路术式治疗对上颌窦内翻性乳头状瘤(Inverting Papilloma, IP)患者机体应激指标的影响与安全性。方法 前瞻性随机选取2019年4月—2023年8月三明市第二医院确诊为上颌窦IP的120例患者为研究对象,按照随机数表法分为两组,每组60例,对照组行鼻内镜下柯陆入路术式处理,观察组行鼻内镜下泪前隐窝入路术式治疗,比较两组的手术基础指标、不同手术阶段的机体应激指标、术后并发症及复发情况。结果 观察组手术时间、术中出血量、术后鼻通气时间、住院时间均优于对照组,差异有统计学意义(P均<0.05)。术后1 d,观察组肾上腺素、皮质醇、转化生长因子β1检测值均低于对照组,差异有统计学意义(P均<0.05)。观察组术后并发症总发生率(3.33%)低于对照组(13.33%),差异有统计学意义(χ^(2)=3.927,P=0.047)。两组术后半年的复发率比较,差异无统计学意义(P>0.05)。结论 鼻内镜下泪前隐窝入路术式、柯陆入路术式用于上颌窦IP患者的治疗远期疗效相当,但前者还具有近期处理效果较好,可减轻机体应激反应,减少并发症发生等优势。 展开更多
关键词 上颌窦内翻性乳头状瘤 鼻内镜 泪前隐窝入路 柯陆入路
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骆驼刺提取物对脂多糖诱导的IEC-6细胞损伤模型NLRP3炎症小体及相关细胞因子的影响
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作者 徐晓琴 卿德刚 +3 位作者 陈良 张娟 孙宇 夏提古丽·阿不利孜 《新疆医科大学学报》 CAS 2024年第5期740-745,754,共7页
目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、AP... 目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、APE低、中、高浓度组,用1.0μg/mL的脂多糖(Lipopolysaccharide,LPS)诱导建立细胞炎症损伤模型,APE(低、中、高浓度:15、25、35μg/mL)干预后采用CCK-8法检测细胞的存活率,通过ELISA试剂盒检测炎症因子IL-1β、IL-18、TNF-α的分泌水平。蛋白质印迹法(WB)检测核苷酸结合寡聚化结构域样受体蛋白3(Nucleotide-binding oligomerization domain-like receptor protein 3,NLRP3)炎症小体信号通路5个关键蛋白:NLRP3、半胱氨酸天冬氨酸蛋白酶1(Cystein-asparate protease-1,Caspase-l)、凋亡相关斑点样蛋白(Apoptosis-associated speck-like protein containing a CARD,ASC)及抗凋亡蛋白Bcl-2(Anti-apoptosis Protein Bcl-2)和Bcl-xl(Anti-apoptosis Protein Bcl-xl)表达。结果与空白组比较,模型组IEC-6细胞的存活率降低,NLRP3、Caspase-1、ASC蛋白表达水平升高,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平降低,促炎因子IL-1β、IL-18和TNF-α的分泌水平升高,差异有统计学意义(P<0.05)。与模型组比较,APE低、中、高浓度组细胞存活率升高,35μg/mL APE组IEC-6细胞的NLRP3、Caspase-1、ASC蛋白相对表达水平降低,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平升高,差异有统计学意义(P<0.05)。中、高浓度的APE能够抑制炎症因子分泌,25μg/mL APE对IL-1β、IL-18、TNF-α炎症因子分泌水平抑制率分别为31.60%、31.19%和31.09%(P<0.05)。结论骆驼刺提取物通过提高抗凋亡蛋白Bcl-2、Bcl-xl的表达水平,下调NLRP3炎症小体组成成分以及促炎因子IL-1β、IL-18和TNF-α分泌,从而抑制NLRP3炎症小体组装和激活,实现缓解LPS对IEC-6细胞的损伤。 展开更多
关键词 骆驼刺提取物 脂多糖 小肠隐窝上皮细胞 NLRP3炎症小体
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CryptDB密文数据库系统并行方案研究
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作者 王伟 杨庚 张成果 《计算机技术与发展》 2017年第2期90-95,共6页
加密数据库对隐私数据的加密存储保护是解决当前互联网中用户隐私数据泄露的一种可行方案。鉴于互联网中每日产生的用户隐私数据规模巨大,传统的串行计算会导致隐私数据的加密存储时间消耗较长。为提高加密存储等数据处理的速度,将MapRe... 加密数据库对隐私数据的加密存储保护是解决当前互联网中用户隐私数据泄露的一种可行方案。鉴于互联网中每日产生的用户隐私数据规模巨大,传统的串行计算会导致隐私数据的加密存储时间消耗较长。为提高加密存储等数据处理的速度,将MapReduce并行框架与Crypt DB密文数据库系统进行有机结合,设计并实现了Crypt DB密文数据库系统并行加密和分布式存储的方案。并行方案采用任务调度算法、文件分割算法来提高其并行性和可控性,通过重写MapReduce框架中的Map方法来实现Crypt DB密文数据库系统的并行加密和分布式存储。基于由1个Master节点、3个Crypt DB节点和3个My SQL服务器构成的实验平台,进行了并行方案的实验验证及其性能分析。实验结果表明,所构建的并行方案在3个Crypt DB节点集群中的加速比可达到2.51,加密和存储时间节省了60.2%,可用于大规模关系数据的加密存储。 展开更多
关键词 加密数据库 MAPREDUCE crypt DB系统 并行加密 分布式存储
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Crypt-JDBC模型:洋葱加密算法的优化改进 被引量:4
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作者 陈鹤 田秀霞 +1 位作者 袁培森 金澈清 《计算机科学与探索》 CSCD 北大核心 2017年第8期1246-1257,共12页
CryptDB是一种典型的密文存储技术,它根据运算操作语义使用洋葱加密算法将SQL语句改写到不同的洋葱密文列,从而仅暴露数据的部分属性即可执行查询任务。针对洋葱加密算法的不足之处提出了一种名为Crypt-JDBC的改进模型:(1)鉴于洋葱层数... CryptDB是一种典型的密文存储技术,它根据运算操作语义使用洋葱加密算法将SQL语句改写到不同的洋葱密文列,从而仅暴露数据的部分属性即可执行查询任务。针对洋葱加密算法的不足之处提出了一种名为Crypt-JDBC的改进模型:(1)鉴于洋葱层数多,且相邻层功能差异大,新模型把洋葱列分为主列与辅助列,并压缩洋葱层的改进方法(主列使用双向算法可还原明文,辅助列使用单向算法提供属性,保证安全性);(2)鉴于等值连接算法复杂低效,新模型通过简化一个关键模块(差异性转换)来降低复杂度;(3)鉴于列名的明文、密文名称对应性弱,新模型重新设计了明密文列名称的对应关系,减少了上下文信息,加强了密钥整体性。实现了Crypt-JDBC模型,用JDBC替换中间件软件MySQL-Proxy。实验结果表明,该模型具有较高的执行效率。 展开更多
关键词 cryptDB 加密数据库 crypt-JDBC模型 洋葱加密算法 密文数据库
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Linux加密文件系统:Crypt-FS 被引量:3
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作者 丁成 孙玉芳 《计算机工程》 CAS CSCD 北大核心 2003年第20期111-113,共3页
随着便携式计算设备的普及,保存数据的存储设备失窃或遗失的可能性增大。在这种情况下,能够保证敏感数据不被泄露的唯一方案是使用数据加密技术。相对于其它加密方式,使用加密文件系统对用户透明、可靠,有着不容忽视的优势。文章在L... 随着便携式计算设备的普及,保存数据的存储设备失窃或遗失的可能性增大。在这种情况下,能够保证敏感数据不被泄露的唯一方案是使用数据加密技术。相对于其它加密方式,使用加密文件系统对用户透明、可靠,有着不容忽视的优势。文章在Linux 2.4操作系统上设计和实现了一个加密文件系统——Crypt-FS,并对其进行了介绍。 展开更多
关键词 LINUX 加密文件系统 安全操作系统 crypt-FS
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Cancer and age related colonic crypt deficiencies in cytochrome c oxidase Ⅰ 被引量:5
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作者 Carol Bernstein Alexander Facista +9 位作者 Huy Nguyen Beryl Zaitlin Nadia Hassounah Cristy Loustaunau Claire Margaret Payne Bhaskar Banerjee Steve Goldschmid V Liana Tsikitis Robert Krouse Harris Bernstein 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2010年第12期429-442,共14页
AIM: To investigate whether defi ciency of expressionof cytochrome c oxidase I (CcOI) in colonic crypts is associated with colon cancer.METHODS: The pattern and level of expression of CcOI in non-neoplastic colonic cr... AIM: To investigate whether defi ciency of expressionof cytochrome c oxidase I (CcOI) in colonic crypts is associated with colon cancer.METHODS: The pattern and level of expression of CcOI in non-neoplastic colonic crypts,and in dysplastic tissues,was assessed using standard immunohis-tochemical methods.Biopsies were obtained from individuals undergoing colonoscopies for screening purposes or for a medically indicated reason.Tissue samples were also obtained from surgical colonic resections.Samples from resections were taken from colonic mucosa 1 and 10 cm from tumors and from the tumors themselves.Samples were evaluated for frequency of crypts with reduced or absent expression of CcOI.In most crypts the loss was apparent throughout the entire crypt,while in a small minority the loss was segmental.The strong immunoreactivity using this monoclonal antibody makes the scoring unambiguous.The percent of crypts with reduced or absent expression of CcOI or (infrequent) segmented loss of expression was then calculated.Data analyses were performed using SPSS statistical package 17.0.RESULTS: The average frequency of CcOI deficient crypts (CcOI-DC) is low in individuals between 20 and 39 years of age,with 0.48% ± 0.40% CcOI-DC for women and 1.80% ± 0.35% for men.CcOI-DC increases after age 40 years,so that between the ages of 40 and 44 years the average frequency of CcOI- DC goes up to 5.89% ± 0.84% in women and 2.15% ± 1.27% in men.By 80-84 years of age,the average frequency of CcOI-DC goes up in women to 15.77% ± 0.97% and in men to 22.6% ± 0.65%.The increases in CcOI-DC from ages 40-44 years compared to 80-84 years in women and men are significantly different with P < 0.01.For women over age 60 years,deficiency of CcOI expression is greater in those women who have had a cancer in their colon.The frequency of CcOI-DC,measured in men,increased in tissues adjacent to colon cancer,being 4.03% ± 0.27% in individuals free of neoplasia in the age range 55-64 yearsand 14.13% ± 0.35% in resected histologically normal tissue of men with cancer in the same age range,P < 0.001.Similar signifi cant differences were noted in older age ranges.The frequency of CcOI-DC crypts in the cecum and sigmoid colon of an individual are signifi cantly correlated,with an R2 = 0.414 for women and R2 = 0.528 for men,P < 0.001.This suggests that the factors determining the level of CcOI deficiency act throughout the colon.Most defective crypts are in clusters of two or more,a likely consequence of crypt fission.In the non-neoplastic margins of cancers,crypts are frequently defi cient for CcOI,and such crypts may appear in large clusters,some containing more than 100 defi cient crypts.CcOI defi ciency is also apparent in colon cancers and sometimes involves a large section of the tumor.Overall,CcOI deficient cells can be visualized in segments of crypts,in whole crypts that increase in frequency with age,in crypts undergoing f ission,in clusters of crypts where the clusters increase in size with age,in increased frequency near tumors,in large clusters in the intimate margins of tumors,and in the tumors themselves.There is no clear dividing line between early stages that can be considered aspects of aging and later stages that can be considered aspects of the progression to cancer.This ambiguity may re ect a rather general situation leading to adult cancer where the early stages of cellular change appear to be relatively innocuous features of the aging process but over decades may evolve into malignancy.CONCLUSION: CcOI defi cient crypts increase in frequency with age,and clusters of defi cient crypts are associated with,and may give rise to,colon cancer. 展开更多
关键词 CYTOCHROME c OXIDASE Aging Colon cryptS Colorectal CANCER Focal lesions
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APC and K-ras gene mutation in aberrant crypt foci of human colon 被引量:21
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作者 Ping Yuan~1 Meng Hong Sun~2 Jin Sheng Zhang~1 Xiong Zeng Zhu~2 Da Ren Shi~2 ~1Department of Pathology,Medical College of Fudan University,~2Department of Pathology,Cancer Hospital/Cancer Institute,Fudan University,Shanghai 200032,ChinaDr.Ping Yuan Studying Province.studying in Medical College of Fudan University,worked in Department of Pathology,Wannan Medical College,having eighteen papers published. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期352-356,共5页
AIM:To study the genetic alteration in ACF and to define the possibility that ACF may be a very early morphological lesion with molecular changes,and to explore the relationship between ACF and colorectal adenoma even... AIM:To study the genetic alteration in ACF and to define the possibility that ACF may be a very early morphological lesion with molecular changes,and to explore the relationship between ACF and colorectal adenoma even carcinoma. METHODS: DNA from 35 CRC, 15 adenomas, 34 ACF and 10 normal mucus was isolated by means of microdissection. Direct gene sequencing of K-ras gene including codon 12, 13 and 61 as well as the mutation cluster region (MCR) of APC gene was performed. RESULTS: K-ras gene mutation frequency in ACF, adenoma and carcinoma was 17.6% (6/34), 13.3% (2/15), and 14.3% (5/35) respectively, showing no difference (P 】 0.05) in K-ras gene mutation among three pathologic procedures. The K-ras gene mutation in adenoma, carcinoma and 4 ACF restricted in codon 12 (GGT GAT), but the other 2 mutations from ACF located in codon 13 (GGC GAC). K-ras gene mutation was found more frequently in older patients and patients with polypoid cancer. No mutation in codon 61 was found in the three tissue types. Mutation rate of APC gene in adenoma and carcinoma was 22.9% (8/35) and 26.7% (4/15), which was higher than ACF (2.9%) (P 【0.05). APC gene mutation in carcinoma was not correlated with age of patients, location, size and differentiation of tumor. CONCLUSION: ACF might be a very early morphological lesion in the tumorogenesis of colorectal tumor. The morphological feature and gene mutation status was different in ACF and adenoma. ACF is possibly putative microadenoma that might be the precursor of adenoma. In addition, the development of a subgroup of colorectal carcinomas might undergo a way of normal epithelium ACF carcinomas . 展开更多
关键词 Genes APC ADENOMA Colorectal Neoplasms DNA Mutational Analysis Gene Frequency Genes ras Humans Point Mutation Research Support Non-U.S. Gov't
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Azoxymethane-induced rat aberrant crypt foci:Relevance in studying chemoprevention of colon cancer 被引量:5
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作者 Jayadev Raju 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第43期6632-6635,共4页
The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous intermediaries. Aberrant crypt foci (ACF) represent the ear... The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous intermediaries. Aberrant crypt foci (ACF) represent the earliest identifiable intermediate precancerous lesions during colon carcinogenesis in both laboratory animals and humans. ACF are easily induced by colon-specific carcinogens in rodents and can be used to learn more about the process of colon carcinogenesis. For over two decades, since its first discovery, azoxymethane (AOM)-induced rodent ACF have served as surrogate biomarkers in the screening of various anticarcinogens and carcinogens. Several dietary constituents and phytochemicals have been tested for their colon cancer chemopreventive efficacy using the ACF system. There has been substantial effort in defining and refining ACF in terms of understanding their molecular make-up, and extensive research in this field is currently in progress. In chemoprevention studies, AOM-induced rat ACF have been very successful as biomarkers, and have provided several standardized analyses of data. There have been several studies that have reported that ACF data do not correlate to actual colon tumor outcome, however, and hence there has been an ambiguity about their role as biomarkers. The scope of this mini-review is to provide valuable insights and limitations of AOM-induced rat ACF as biomarkers in colon cancer chemoprevention studies. The role of the dynamics and biological heterogeneity of ACF is critical in understanding them as biomarkers in chemoprevention studies. 展开更多
关键词 Aberrant crypt foci AZOXYMETHANE Biological markers CARCINOGENESIS CHEMOPREVENTION Colon cancer
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Aberrant crypt focus and fragile histidine triad protein in sporadic colorectal carcinoma 被引量:2
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作者 Kim Vaiphei Aruna Rangan Rajinder Singh 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2012年第12期250-258,共9页
AIM:To characterize aberrant crypt focus (ACF) in adjoining mucosa in sporadic colorectal carcinoma and to evaluate fragile histidine triad (Fhit) protein and Ki67. METHODS:ACF was identified grossly and classified hi... AIM:To characterize aberrant crypt focus (ACF) in adjoining mucosa in sporadic colorectal carcinoma and to evaluate fragile histidine triad (Fhit) protein and Ki67. METHODS:ACF was identified grossly and classified histologically in 75 resected specimens. ACF was typed into hyperplastic ACF (HACF) and dysplastic ACF (DACF). Sections of ACF, carcinoma and normal colonic mucosa as control were studied for Fhit and Ki67 expressions by immunohistochemistry and were grouped according to staining intensity and the number of positive stained cells observed in different histological groups. Comparison was done between the different groups by Pearson's χ 2 test and γ test for the ordinal data. P value < 0.05 was considered as significant.RESULTS:Age range was 40 to 86 years in males (mean = 43.36) and 45 to 70 years in females (mean = 56). HACF was identified in all cases studied in the non-tumorous colonic mucosa; ACF was observed as non-contiguous scattered foci, which supports the hypothesis of acquisition of single focus monoclonality by colonic epithelial cells in tumor generation. Twenty-four (32%) had DACF and were observed as closure to carcinoma foci. Intensity of Fhit expression:(1) HACF 40% exhibited strong intensity, similar to normal, moderate in 36% and weak in 24%; (2) DACF strong in 25%, moderate in 37.5% and weak in 37.5%; and (3) carcinoma negative in 16%, strong in 43% and moderate and weak in 28.5% each. Significant difference was observed in intensity of the Fhit protein expressions by HACF and DACF (P < 0.05). Tumor in older patients showed a stronger Fhit intensity compared to younger patients (P = 0.036). Vegetarian diet intake and nonsmokers showed stronger Fhit intensities. Advanced stage tumor, non-vegetarian diet and younger age was associated with loss of Fhit protein. Ki67 positivity was an extended crypt pattern in HACF and DACF showed extension up to the neck region of the crypts and surface epithelium. Carcinomas showed a marked increase in Ki67 expression (P < 0.05). Fhit protein had an inverse association with Ki67 expression. CONCLUSION:Weaker Fhit intensity was associated with smoking, non-vegetarian diet intake and increasing Ki67 expression. Loss of Fhit protein expression is possibly influenced by environmental factors like smoking and non-vegetarian diet intake. 展开更多
关键词 ABERRANT crypt FOCUS Carcinogenesis Colorectal carcinoma Dysplasia Fragile HISTIDINE TRIAD PROTEIN Ki67
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Crypt abscess-associated microbiota in inflammatory bowel disease and acute self-limited colitis 被引量:2
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作者 Harry Sokol Nadia Vasquez +5 位作者 Nadia Hoyeau-Idrissi Philippe Seksik Laurent Beaugerie Anne Lavergne-Slove Philippe Pochart Philippe Marteau 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第5期583-587,共5页
AIM:To evaluate whether crypt abscesses frominflammatory bowel disease(IBD)patients containbacteria and to establish their nature.METHODS:We studied 17 ulcerative colitis patients,11 Crohn's disease patients,7 pat... AIM:To evaluate whether crypt abscesses frominflammatory bowel disease(IBD)patients containbacteria and to establish their nature.METHODS:We studied 17 ulcerative colitis patients,11 Crohn's disease patients,7 patients with acute selflimited colitis(ASLC)and normal colonic biopsies from5 subjects who underwent colonoscopy for colon cancer screening.A fluorescent in situ hybridization techniquewas applied to colonic biopsies to assess the microbiotacomposition of the crypts and crypt abscesses.RESULTS:Crypts colonized by bacteria were observedin 42.9%and 3.6%of ASLC and IBD patients,respectively(P=0.019).Crypt abscesses colonized bybacteria were observed in 28.6%and 0.0%of ASLCand IBD patients,respectively(P=0.035).CONCLUSION:These results do not support thehypothesis that crypt abscesses in IBD are the resultof localized dysbiosis arising from persistence of livingbacteria colonizing the crypts. 展开更多
关键词 Inflammatory bowel diseases Crohn’sdisease Ulcerative colitis crypt abscess MICROBIOTA
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Relationship of human rectal aberrant crypt foci and formation of colorectal polyp:One-year following up after polypectomy
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作者 Hirokazu Takahashi Eiji Yamada +6 位作者 Hidenori Ohkubo Eiji Sakai Takuma Higurashi Takashi Uchiyama Kunihiro Hosono Hiroki Endo Atsushi Nakajima 《World Journal of Gastrointestinal Endoscopy》 CAS 2012年第12期561-564,共4页
AIM:To clarify the relationship of human rectal aberrant crypt foci and formation of colorectal polyp.METHODS:Eighty-nine subjects were recruited from the population of Japanese individuals who underwent polypectomy a... AIM:To clarify the relationship of human rectal aberrant crypt foci and formation of colorectal polyp.METHODS:Eighty-nine subjects were recruited from the population of Japanese individuals who underwent polypectomy at Yokohama City University Hospital.All patients had baseline adenomas removed at year 0 colonoscopy.Aberrant crypt foci(ACF) were defined as lesions in which the crypts were more darkly stained with methylene blue than normal crypts and had larger diameters,often with oval or slit-like lumens and a thicker epithelial lining.RESULTS:A total of 366 ACFs were identified in 89 patients;all had baseline adenomas removed at the first examination(year 0) colonoscopy and returned for the second(year 1).ACF in the lower rectum were assessed at year 0 and study group were divided into two groups depend on ACF numbers,0-3 or over 3.All participants were examined in the number and maximum size of adenoma.There was no statistical difference in number and maximum size of ACF at year 0,however,maximum size of adenoma was larger in over 3 group than 0-3 group at year 1.CONCLUSION:The number of ACF may be a predictive factor of relatively large adenoma incidence in the pilot phase study. 展开更多
关键词 ABERRANT crypt FOCI Colorectal carcinogenesis VISCERAL fat ADIPONECTIN
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INHIBITORY EFFECT OF FERMENTED MILK ON DMH-INDUCED MICRO-NUCLEI AND APOPTOSIS IN THE COLON CRYPT CELLS OF MICE
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《癌变.畸变.突变》 CAS CSCD 1991年第S1期266-266,共1页
The effect of fermented milk on micronuclei andapoptosis induced by DimethyIhydraziine(DMH)in thecolon crypt cells of mouse was studied.Fermented milk,milk and tap water were fed to three groups of C57BL mice.The anim... The effect of fermented milk on micronuclei andapoptosis induced by DimethyIhydraziine(DMH)in thecolon crypt cells of mouse was studied.Fermented milk,milk and tap water were fed to three groups of C57BL mice.The animals were given DMH i.p.at a dosage of 20mg/kg onthe 7th day.The animals were sacrificed 24 hours 展开更多
关键词 DOSAGE crypt COLON inhibited noted TUMORIGENESIS
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Crypt region localization of intestinal stem cells in adults
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作者 Hugh James Freeman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第47期7160-7162,共3页
The intestinal epithelial lining plays a central role in the digestion and absorption of nutrients,but exists in a harsh luminal environment that necessitates continual renewal.This renewal process involves epithelial... The intestinal epithelial lining plays a central role in the digestion and absorption of nutrients,but exists in a harsh luminal environment that necessitates continual renewal.This renewal process involves epithelial cell proliferation in the crypt base and later cell migration from the crypt base to the luminal surface.This process is dependent on multi-potent progenitor cells,or stem cells,located in each crypt.There are about 4 to 6 stem cells per crypt,and these stem cells are believed to generate distinct end-differentiated epithelial cell types,including absorptive cells,goblet cells,enteroendocrine cells and Paneth cells,while also maintaining their own progenitor cell state.Earlier studies suggested that intestinal stem cells were located either in the crypt base interspersed between the Paneth cells [i.e.crypt base columnar(CBC) cell model] or at an average position of 4 cells from the crypt base [i.e.label-retaining cells(LRC +4) model].Recent studies have employed biomarkers in the in vivo mammalian state to more precisely evaluate the location of these progenitor cells in the intestinal crypt.Most notable of these novel markers are Lgr5,a gene that encodes a G-protein-coupled receptor with expression restricted to CBC cells,and Bmi 1,which encodes a chromatin remodeling protein expressed by LRC.These studies raise the possibility that there may be separate stem cell lines or different states of stem cell activation involved in the renewal of normal mammalian intestinal tract. 展开更多
关键词 crypt base columnar cells Intestinal epithelial cell renewal Lgr5 gene Polycomb bmil protein Progenitor cells Stem cells +4 stem cellmodel
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亚硒酸二葡萄糖酯对产蛋后期蛋鸭肠道形态和微生物的影响 被引量:1
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作者 张旭 李闯 +5 位作者 黄璇 蒋桂韬 邓萍 刘胜利 李昊帮 戴求仲 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第1期100-106,共7页
选用240只50周龄健康的临武鸭蛋鸭,随机分成5组:对照组(第1组)在基础饲粮中添加0.2 mg/kg(以硒计)的亚硒酸钠,第2、3、4、5组分别在基础饲粮中添加0.1、0.2、0.3、0.4mg/kg(以硒计)的亚硒酸二葡萄糖酯。每组6个重复,每重复8只鸭。预试期... 选用240只50周龄健康的临武鸭蛋鸭,随机分成5组:对照组(第1组)在基础饲粮中添加0.2 mg/kg(以硒计)的亚硒酸钠,第2、3、4、5组分别在基础饲粮中添加0.1、0.2、0.3、0.4mg/kg(以硒计)的亚硒酸二葡萄糖酯。每组6个重复,每重复8只鸭。预试期7d,正试期63d。试验结束后测定供试鸭的十二指肠、空肠和回肠形态指标及回肠和盲肠的微生物多样性。结果表明:与对照组相比,饲粮添加亚硒酸二葡萄糖酯对产蛋后期蛋鸭的十二指肠、空肠和回肠绒毛高度、隐窝深度、肠壁厚度、绒毛高度与隐窝深度的比值均无显著影响;添加亚硒酸二葡萄糖酯组降低了回肠中变形菌门和埃希氏菌属–志贺氏杆菌属及盲肠中变形菌门和厌氧螺菌属的相对丰度,提高了回肠中肠杆菌属及盲肠中拟杆菌门和普雷沃氏菌属、肠杆菌属、理研菌科RC9菌属的相对丰度;第2组回肠中属、种水平的OTU数显著高于对照组的,肠道菌群α多样性最高,回肠中厚壁菌门相对丰度最高且埃希氏菌属–志贺氏杆菌属相对丰度最低,盲肠中拟杆菌门相对丰度最高。综上可知,饲粮添加亚硒酸二葡萄糖酯降低了回肠中有害微生物的相对丰度,有利于肠道健康,饲粮中亚硒酸二葡萄糖酯的适宜添加量为0.1mg/kg(以硒计)。 展开更多
关键词 蛋鸭 亚硒酸二葡萄糖酯 肠道绒毛高度 隐窝深度 肠壁厚度 肠道微生物
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EPITHELIAL CELL NECROSES IN MOUSE INTESTINAL CRYPTS AFTER CONTINUE IRRADIATION WITH βRAYS FROM TRIATED WATER
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《癌变.畸变.突变》 CAS CSCD 1991年第S1期254-254,共1页
In this paper epithelial cell necroses(apoptosis)of mouse intestinal crypts induced by βRays fromtritiated water(HTO)was reported.The resultsshowed that the number of apoptotic cells perintestinal crypt 20 hrs after ... In this paper epithelial cell necroses(apoptosis)of mouse intestinal crypts induced by βRays fromtritiated water(HTO)was reported.The resultsshowed that the number of apoptotic cells perintestinal crypt 20 hrs after injection of 展开更多
关键词 CELL crypt
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爱迪德公司签约昆明市广播电视网络——通过使用爱迪德M—Crypt昆明市网络广播电视将提供给用户数字付费电视服务
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《广播电视信息》 2002年第10期68-68,共1页
关键词 爱迪德公司 条件接收系统 M—crypt 昆明市 广播电视网络 数字付费电视
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