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1.
目前认为,幽门螺杆菌(Hp)是慢性胃炎和消化性溃疡的主要病因,是胃癌和胃淋巴瘤发生的重要因素之一,1994年WHO将其列为第Ⅰ类生物致癌因子.Hp定植在胃黏膜上皮和黏液层之间,引起胃黏膜炎症.  相似文献   

2.
目前认为,幽门螺杆菌(Hp)是慢性胃炎和消化性溃疡的主要病因,是胃癌和胃淋巴瘤发生的重要因素之一,1994年WHO将其列为第Ⅰ类生物致癌因子.Hp定植在胃黏膜上皮和黏液层之间,引起胃黏膜炎症.  相似文献   

3.
张卫宁  曹彬 《中华消化杂志》2009,30(10):412-413
目前认为,幽门螺杆菌(Hp)是慢性胃炎和消化性溃疡的主要病因,是胃癌和胃淋巴瘤发生的重要因素之一,1994年WHO将其列为第Ⅰ类生物致癌因子.Hp定植在胃黏膜上皮和黏液层之间,引起胃黏膜炎症.  相似文献   

4.
5.
目的 探究幽门螺杆菌(Helicobacter pylori,Hp)感染对蒙古沙鼠胃组织中NLRP3炎症小体相关因子和自噬相关蛋白表达的影响。方法 采用Hp国际标准株11637灌胃处理蒙古沙鼠,隔天一次,共5次,以相同体积无菌脑心浸液肉汤灌胃的沙鼠作为对照组。于感染第3、6、12和24个月后处死沙鼠,取胃黏膜组织并切片,HE染色后作病理学检查;免疫组织化学染色观察Hp定植;试剂盒法检测胃组织NLRP3炎症小体及其相关因子IL-18、IL-β和自噬相关蛋白P62、LC3的表达。结果 Hp感染蒙古沙鼠胃组织检测到Hp的定植,HE染色检查显示不同时间感染组沙鼠胃黏膜均出现糜烂黏膜下层组织水肿、黏膜局部浅表糜烂和淋巴浆细胞浸润等不同程度的慢性胃炎病理改变,感染24月部分区域出现非典型增生甚至癌变。对照组沙鼠均无Hp定植及组织学病变。与未感染对照组比较,Hp感染蒙古沙鼠胃组织中NLRP3、IL-18、IL-1β和LC3、P62的表达水平均显著升高(均P<0.05);其中NLRP3、IL-18、LC3表达3到12个月随着Hp感染时间的延长呈升趋势,12到24个月呈下降趋势。IL-1β表达无显...  相似文献   

6.
幽门螺杆菌感染对Fas/FasL表达的影响在胃癌发生中的作用   总被引:8,自引:0,他引:8  
目的:观察幽门螺杆菌(Hp)及其不同毒力株(cagA阳性与cagA阴性株)感染对胃黏膜上皮细胞Fas/FasL表达的影响,进而探讨胃癌的发生机制。方法:胃镜下取胃窦黏膜标本,将研究对象按病理结果分为黏膜萎缩组,黏膜萎缩伴轻度不典型增生组,黏膜萎缩伴中度不典型增生组,胃腺癌组,黏膜大致正常组为对照组,再根据Hp感染情况为分Hp阳性组与阴性组,并将Hp阳性组进一步成cagA阳性组及阴性组,共9组80例。以快速尿素酶试验,PCR及组织学第三种方法检测Hp,用PCR方法对Hp进行分型。用免疫组化法检测Fas、FasL等表达情况。结果Hp感染率为60.0%,cagA阳性率为90.47%,非腺癌病人Hp阳性组Fas/FasL表达明显高于Hp阴性组(P<0.05),腺癌组Fas/FasL表达明显高于大致正常组及黏膜萎缩,黏膜萎缩伴轻度不典型增生,黏萎缩伴中度不典型增生组(P<0.01)。cagA阳性组Fas/FasL表达与cagA阴性组差异无显著性(P>0.05)。结论:幽门螺杆菌感染后早期即黏 萎缩阶段已出现Fas、FasL等的表达增加,随细胞凋亡的增加,黏膜上皮细胞萎缩加重,细胞DNA不稳定性增加,并出现不典型增生加重, Fas、FasL的表达随之增强,一旦肿瘤细胞形成,Fas/FasL表达进一步增加,形成局部免疫豁免区,导致肿瘤的浸润生长。cagA阳性的菌株在促成肿瘤的发生过程中无明显作用。  相似文献   

7.
幽门螺杆菌(Hp)属于革兰阴性菌,可以在人胃内存活并定植。Hp能够利用其毒力因子调节宿主炎症反应,破坏胃黏膜,其感染的长期结局包括胃癌和胃黏膜相关淋巴组织淋巴瘤等恶性肿瘤,是与胃癌相关的Ⅰ类致癌物。与Hp生存相关的毒力因子主要是脲酶,在脲酶的帮助下,Hp可以在pH值极低的胃内生存,形成持久感染;与Hp定植相关的毒力因子包括外部炎症蛋白A、Hp外膜蛋白Q、血型抗原结合黏附素,这些毒力因子与宿主胃上皮细胞相互作用,帮助Hp在胃黏膜定植,增加癌前病变及胃癌发生风险;与Hp致病相关的毒力因子包括细胞毒素相关基因A、空泡细胞毒素、外膜囊泡、γ-谷氨酰转肽酶、高温需求蛋白A等,Hp在胃上皮细胞存活、黏附并成功定植后,上述毒力因子进一步诱导炎症反应,促进细胞增殖、侵袭和转移,促使胃部炎症向胃癌转化。深入研究Hp毒力因子诱导胃癌发生的机制,有助于为胃癌的诊断和治疗提供新思路和方法。  相似文献   

8.
目的 分析接受内镜下黏膜剥离术(ESD)治疗的早期胃癌患者幽门螺杆菌(Hp)感染及耐药情况。方法 选择430例行ESD治疗的早期胃癌患者,对患者进行13C尿素呼气试验,判断Hp感染情况。收集患者临床病理资料,采用多因素Logistic回归分析Hp感染的危险因素。对Hp感染患者ESD手术切除病变前行放大内镜评估并切除胃体、胃窦黏膜组织,采用平皿掺入法进行Hp菌株培养和鉴定,采用琼脂稀释法对获得的Hp菌株进行常用抗菌药物的体外敏感性试验。结果 430例患者中,Hp感染318例,Hp感染率为73.95%。有家族史、组织分化程度为分化型、浸润深度为黏膜下癌、周围黏膜高度萎缩、有肠化、高度异型增生患者的Hp感染率分别高于无家族史、组织分化成为为未分化型、浸润深度为黏膜内癌、周围黏膜中低度萎缩、无肠化、低度异型增生患者(P均<0.05)。家族史、浸润深度、周围黏膜萎缩程度、有无肠化、有无异型增生是早期胃癌患者Hp感染的独立影响因素(P均>0.05)。取318例Hp感染患者的胃黏膜组织进行培养,共分离出248株Hp菌株。药敏试验显示,248株Hp菌株对甲硝唑耐药率97.98%,克拉霉素耐...  相似文献   

9.
胃微生态平衡是人体健康的重要前提,幽门螺杆菌(Helicobacter pylori,Hp)是目前已发现的与胃癌相关的关键病原体之一,普遍存在于人胃黏膜上皮。Hp感染可引起胃内其他菌群的改变,还可引起长期慢性的胃黏膜损伤,导致一系列胃黏膜上皮恶性进展和胃癌的发生。本文就胃微生态与Hp感染的关系、Hp感染在胃癌发生中的作用、胃内其他菌群在胃癌发生中的作用及微生态制剂在胃癌治疗的作用进行综述。进一步揭示Hp感染对胃微生态平衡的影响,胃微生态平衡和Hp感染在胃癌发生发展中的作用及微生态制剂在胃癌治疗中的意义。  相似文献   

10.
目的:评价幽门螺杆菌(Hp)感染时胃细胞Fas/Fas Lingand的表达,功能及其对胃上皮细胞的损伤作用,以了解Hp的免疫致病机制,方法:免疫组化方法检测Hp阳性及阴性胃黏膜FasLigand的表达情况,RT-PCR检测胃T细胞FasLigand mRNA的表达,生物检测技术(JAM)评价胃T细胞通过Fas/Fas Ligand作用杀伤靶细胞的活性,并对Fas/Fas Ligand介导的胃T细胞及培养上清致胃型上皮凋亡进行了检测,结果:Hp感染胃组织中单核细胞Fas Ligand阳性而Hp阴性者无表达,Hp阳性胃黏膜T细胞系表达Fas Ligand mRNA,而Hp阴性者则不表达或弱表达,胃T细胞的Fas Ligand具有生物学活性,能杀伤Fas阳笥的Jurkat细胞并特异杀伤胃上皮细胞系,结论:通过激活胃浸润T细胞的Fas Ligand表达而损伤胃型上皮是Hp免疫致病的机制之一,其在Hp感染时黏膜免疫选择中的作用尚需进一步探讨。  相似文献   

11.
目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤,因其临床表现多样,导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用,拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点,以期有助于提高影像学的诊断准确率和降低漏诊率,尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料,检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例,通过查阅病例的方法,提取出胰岛素瘤的大小和解剖分布等数据,进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例,其中,男45例、女71例,年龄13~76岁,平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布:头颈部46例(39.7%),单发45例、多发1例;体尾部68例(58.6%),单发65例、多发3例;全胰腺多发2例(1.7%)。病变大小特点:最大径0.4~3.4 cm,平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例,≤3 cm 15例,>3 cm 3例。年龄与肿瘤的大小相关,≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm,P<0.05。头颈部的肿瘤大于体尾部的肿瘤,头颈部肿瘤平均大小(1.66±0.63)cm,体尾部(1.42±0.52)cm,P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发;绝大多数单发,但可以全胰腺多发;多数小于1.5 cm,肿瘤的大小与患者年龄和肿瘤的解剖分布相关。  相似文献   

12.
Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.  相似文献   

13.
Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.  相似文献   

14.
BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.  相似文献   

15.
血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。  相似文献   

16.
目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。  相似文献   

17.
氯硝柳胺悬浮剂的毒性评价   总被引:2,自引:2,他引:2  
目的评价氯硝柳胺悬浮剂的毒性,为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg,经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3,该药经口、经皮肤、经呼吸道毒性均属微毒类药物;兔眼用药后,观察期内无不良反应,对眼无刺激性;皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比,氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物,对鱼的毒性低于其乙醇胺盐可湿性粉剂,适合于现场应用。  相似文献   

18.
The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002  相似文献   

19.

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl−1•min−1 (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl−1•min−1 (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.  相似文献   

20.
The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H2-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.  相似文献   

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