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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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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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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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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 被引量:1
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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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Successful microsurgical vasoepididymostomy for a case of cryptozoospermia
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作者 Ru-Hui Tian Yu-Hua Huang +5 位作者 Hui-Xing Chen Peng Li Er-Lei Zhi Chen-Cheng Yao Chao Yang Zheng Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2022年第4期436-437,共2页
Dear Editor,Cryptozoospermia is defined as the apparent absence of spermatozoa from fresh semen samples,but they can.be found in centrifuged pellets.1 It is usually caused by a spermatogenic disorder,while cryptozoosp... Dear Editor,Cryptozoospermia is defined as the apparent absence of spermatozoa from fresh semen samples,but they can.be found in centrifuged pellets.1 It is usually caused by a spermatogenic disorder,while cryptozoospermia associated with seminal duct obstruction is less common.2 Because of the extremely low sperm counts in semen samples,men with cryptozoospermia are often reliant on intracytoplasmic sperm injection(ICSI)for paternity. 展开更多
关键词 INJECTION crypt OBSTRUCTION
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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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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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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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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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欧洲电信标准协会发布量子安全混合密钥交换新标准
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《质量与标准化》 2025年第4期46-46,共1页
事件:ETSI TS 104015:2015《具有隐藏访问策略的高效量子安全混合密钥交换》发布内容:3月25日,欧洲电信标准协会(ETSI)发布《具有隐藏访问策略的高效量子安全混合密钥交换》(ETSI TS 104015:2015),旨在保障关键数据和通信安全。该标准... 事件:ETSI TS 104015:2015《具有隐藏访问策略的高效量子安全混合密钥交换》发布内容:3月25日,欧洲电信标准协会(ETSI)发布《具有隐藏访问策略的高效量子安全混合密钥交换》(ETSI TS 104015:2015),旨在保障关键数据和通信安全。该标准所定义的Cover crypt,是一种带有访问控制的密钥封装机制(KEMAC)。 展开更多
关键词 量子安全 ETSI Cover crypt 混合密钥交换
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Early weaning leads to the remodeling of lipid profile in piglet jejunal crypt cells during post-weaning days 被引量:3
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作者 Yirui Shao Xia Xiong +5 位作者 Kexing Wang Pi Cheng Lijun Zou Jian Zhou Ming Qi Yulong Yin 《Animal Nutrition》 SCIE CSCD 2022年第4期102-111,共10页
Reportedly,proteins involved in lipid metabolism change significantly in the jejunal crypt cells of earlyweaned piglets,but the exact lipid profile change remains uncertain.In the present study,32 piglets weaned at 21... Reportedly,proteins involved in lipid metabolism change significantly in the jejunal crypt cells of earlyweaned piglets,but the exact lipid profile change remains uncertain.In the present study,32 piglets weaned at 21 d of age were randomly divided into 4 groups with 8 replicates.The jejunal crypt cells of a group of piglets on the post-weaning day(PWD)1,3,7,and 14 were isolated per time point.Crypt cell lipid profiles were analyzed using ultra-high-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry.This study showed that piglets suffered the greatest weaning stress on PWD 3 in terms of the lowest relative weight of the small intestine,the highest relative weight of the spleen,and the highest levels of malondialdehyde,cholesterol,and low-density lipoprotein cholesterol.The lipid profile of jejunal crypt cells including carnitine,sulfatide,sphingomyelin,hexosylceramide,and ceramide greatly changed after weaning,especially between PWD3 and 14(P<0.05).The differential lipid species between these 2 d were mainly involved in the glycerophospholipid metabolism pathway.In addition,potential lipid biomarkers for weaning stress in crypt cells such as phosphatidylcholine(PC)(9:0/26:1),PC(17:0/18:2),carnitine(24:0),carnitine(22:0),sphingomyelin(d14:1/22:0),PC(P-18:0/18:4),phosphatidylethanolamine(P-16:0/20:4),phosphatidylinositol(15:1/24:4),and dihexosylceramide(d14:1/26:1)were identified.The changes in lipid profile might be related to the inflammation caused by early weaning.These findings might provide new therapeutical targets for intestinal dysfunctions caused by weaning stress. 展开更多
关键词 Early-weaned piglet Weaning stress crypt cell LIPIDOMICS INFLAMMATION
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Modeling colorectal tumorigenesis using the organoids derived from conditionally immortalized mouse intestinal crypt cells (ciMICs) 被引量:4
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作者 Xiaoxing Wu Zhaoxia Li +24 位作者 Hongyu Zhang Fang He Min Qiao Huaxiu Luo Jing Zhang Meng Zhang Yukun Mao William Wagstaff Yongtao Zhang Changchun Niu Xia Zhao Hao Wang Linjuan Huang Deyao Shi Qing Liu Na Ni Kai Fu Rex C.Haydon Russell R.Reid Hue H.Luu Tong-Chuan He Ziwei Wang Houjie Liang Bing-Qiang Zhang Ning Wang 《Genes & Diseases》 SCIE 2021年第6期814-826,共13页
Intestinal cancers are developed from intestinal epithelial stem cells(ISCs)in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes.ISCs play a key role ... Intestinal cancers are developed from intestinal epithelial stem cells(ISCs)in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes.ISCs play a key role in maintaining the homeostasis of gut epithelium.In 2009,Sato et al established a three-dimensional culture system,which mimicked the niche microenvironment by employing the niche factors,and successfully grew crypt ISCs into organoids or Mini-guts in vitro.Since then,the intestinal organoid technology has been used to delineate cellular signaling in ISC biology.However,the cultured organoids consist of heterogeneous cell populations,and it was technically challenging to introduce genomic changes into three-dimensional organoids.Thus,there was a technical necessity to develop a twodimensional ISC culture system for effective genomic manipulations.In this study,we established a conditionally immortalized mouse intestinal crypt(ciMIC)cell line by using a piggyBac transposon-based SV40 T antigen expression system.We showed that the ciMICs maintained long-term proliferative activity under two-dimensional niche factor-containing culture condition,retained the biological characteristics of intestinal epithelial stem cells,and could form intestinal organoids in three-dimensional culture.While in vivo cell implantation tests indicated that the ciMICs were non-tumorigenic,the ciMICs overexpressing oncogenic b-catenin and/or KRAS exhibited high proliferative activity and developed intestinal adenoma-like pathological features in vivo.Collectively,these findings strongly suggested that the engineered ciMICs should be used as a valuable tool cell line to dissect the genetic and/or epigenetic underpinnings of intestinal tumorigenesis. 展开更多
关键词 Cancer modeling Conditional immortalization Mini-gut organoids Mouse intestinal crypt(MIC)cells Tumorigenesis
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肠黏膜上皮-肌成纤维细胞共培养模型的构建与评价
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作者 于朋鑫 王明琦 +2 位作者 郭丽娜 于禹 王秀丽 《解剖学报》 2025年第4期438-443,共6页
目的 体外构建可模拟在体肠道黏膜结构的三维仿生模型。方法 以具有绒毛隐窝结构的丝素蛋白为支架,Caco-2和HT29-MTX-E12为种子细胞,与肌成纤维细胞进行体外三维共培养,构建肠黏膜上皮-肌成纤维细胞共培养模型,通过对细胞标志性蛋白及... 目的 体外构建可模拟在体肠道黏膜结构的三维仿生模型。方法 以具有绒毛隐窝结构的丝素蛋白为支架,Caco-2和HT29-MTX-E12为种子细胞,与肌成纤维细胞进行体外三维共培养,构建肠黏膜上皮-肌成纤维细胞共培养模型,通过对细胞标志性蛋白及基因的检测探索模型细胞的生长、活性、组织学特性以及功能基因的表达。结果 1.成功构建了肠黏膜上皮-肌成纤维细胞共培养模型,活性良好。2.共培养模型中肠上皮细胞黏液分泌增加,muc2基因表达上调。结论 具有绒毛隐窝结构的肠黏膜上皮-肌成纤维细胞共培养能够促进肠上皮细胞功能性分化,能够更好地模拟在体肠道黏膜结构与功能。 展开更多
关键词 肠黏膜上皮模型 丝素蛋白 绒毛隐窝 三维共培养
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骨髓间充质干细胞条件培养基修复坏死性小肠结肠炎肠上皮损伤
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作者 张丽君 沙卫红 陈浩 《现代消化及介入诊疗》 2025年第1期6-9,13,共5页
目的本研究旨在探讨骨髓间充质干细胞条件培养基(Mesenchymal stem cell-conditioned medium,MSC-CM)对坏死性小肠结肠炎肠上皮的修复作用。方法我们将大鼠小肠隐窝上皮细胞(IEC-6)分为对照组、NEC损伤组和NEC损伤+治疗组,后两组经受脂... 目的本研究旨在探讨骨髓间充质干细胞条件培养基(Mesenchymal stem cell-conditioned medium,MSC-CM)对坏死性小肠结肠炎肠上皮的修复作用。方法我们将大鼠小肠隐窝上皮细胞(IEC-6)分为对照组、NEC损伤组和NEC损伤+治疗组,后两组经受脂多糖诱导以构建NEC的体外模型,其中对照组和NEC损伤组加入正常培养基,而NEC损伤+治疗组则加入MSC-CM。采用酶联免疫吸附试验(ELISA)和荧光定量PCR(qPCR)来检测肿瘤坏死因子α(TNF-α)、白细胞介素-1β(IL-1β)、白介素6(IL-6)以及白介素10(IL-10)的表达水平。PCNA法和Tunel法检测细胞增殖和凋亡。结果与对照组和NEC损伤组相比,经过MSC-CM干预后,NEC损伤+治疗组促炎因子TNF-α、IL-1β、IL-6的水平,细胞凋亡水平显著降低(P<0.05),而抗炎因子IL-10水平和细胞增殖水平显著提高(P<0.05)。结论MSC-CM可能通过抑制炎症反应以及细胞凋亡,增进细胞增殖以修复NEC损伤的小肠隐窝上皮细胞,这为NEC提供了有前途的药物。 展开更多
关键词 骨髓间充质干细胞 条件培养基 小肠隐窝上皮细胞 坏死性小肠结肠炎
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