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1.
幽门螺杆菌(Helicobacter pylori,H.pylori)是一种常见的引起多种胃肠道疾病的病原体。临床中通常利用具有不同灵敏度和特异性的侵入性或非侵入性诊断方法来检测H.pylori的感染。目前,诊断H.pylori的方法包括尿素呼气试验、粪便抗原试验、血清学、内镜检查、胃活检组织学、快速尿素酶试验、培养、分子生物学方法等。在实际临床实践中,考虑不同的医疗条件、医生的专业水平、检测成本、敏感性和特异性等多方面因素,如何合理地选择一种或多种方法来诊断H.pylori感染进而指导临床预防和治疗,是一项重要的临床研究课题。本文将对H.pylori感染诊断方法的最新进展、不同方法的优缺点以及其在临床实践中的应用作一综述。  相似文献   

2.
幽门螺杆菌抗生素耐药机制研究进展   总被引:2,自引:0,他引:2  
幽门螺杆菌(Helicobacter pylori,H.pylori)感染可引起消化性溃疡、胃粘膜相关淋巴组织淋巴瘤和胃癌。随着抗生素耐药性的问题越来越严重,耐药机制的研究也不断深入。分子检测方法,尤其是核酸检测技术,可高效、快速、准确地检测幽门螺杆菌抗生素耐药基因及突变,对幽门螺杆菌感染的临床治疗发挥重要的指导作用,同时也可对幽门螺杆菌抗生素耐药性进行大规模及时有效监控。本文讨论了关于幽门螺杆菌抗生素耐药机制并着重总结了相关耐药基因及突变。  相似文献   

3.
目的了解慢性腹痛患儿幽门螺杆菌(H.pylori)的感染状态及幽门螺杆菌感染患儿内镜下表现的特点。方法应用C13尿素呼气试验,对905例以慢性腹痛为主要症状的患儿进行检测,对C13呼气试验阳性者进行电子胃镜检查。结果905例慢性腹痛患儿中H.pylori呈阳性185例(20.44%),随年龄增长,其H.pylori阳性率升高,学年组已达高峰。对H.pylori阳性者进行胃镜检查结果显示十二指肠隆起病变47例占25.40%,结节性胃炎41例占22.1%,慢性浅表性`胃炎38例占20.5%,结节性胃炎伴十二指肠隆起病变23例占12.43%,十二指肠球部溃疡23例占12.4%。胃溃疡7例,占3.7%(其中包括1例复合性溃疡),结节性胃炎伴十二指肠炎6例,占3.2%。结论H.pylori感染为小儿慢性腹痛的主要原因之一,也是导致慢性胃炎及消化性溃疡的主要原因之一。C13尿素呼气试验方便,快速,无痛苦,无放射性,是一较好的H.pylori检测方法;对既有消化道症状同时C13呼气试验阳性者进行胃镜检查能够协助临床诊断及治疗。  相似文献   

4.
目的:探讨幽门螺杆菌(Hpylori)菌株中cagA和hrgA基因对胃癌的致病作用及其检测的意义。方法:胃癌及消化性溃疡术后切除标本,组织学检查,快速尿素酶法和PCR检测。结果:40例标本经组织学检查24例为胃腺癌,2例为胃黏膜相关淋巴样组织(MALT)瘤,14例为消化性溃疡。经快速尿素酶法检测,胃腺癌中,12例H pylori( ),消化性溃疡中,12例H pylori( )。经PCR检测,胃腺癌中,18例hrgA( ),6例hrgA(-),20例cagA( ),4例cagA(-);消化性溃疡中,6例hrgA( ),8例hrgA(-),12例cagA( ),2例cagA(-)。结论:H pylori感染与胃癌的发生有密切关系。PCR检测较快速尿素酶法准确。检测cagA和hrgA基因对了解Hpylori菌株的致病性、估计疾病程度、了解病变预后及临床治疗都具有重要意义。  相似文献   

5.
目的评估改良幽门螺杆菌抗原检测试剂盒检测粪便幽门螺杆菌抗原(Helicobacter pylori stool antigen,HpSA)的准确性以及临床应用价值。方法采用随机、双盲、双验证和与~(13) C呼气试验(~(13) C-UBT)对比的方法,对门诊175例接受~(13) C-UBT检测的患者,采用最新研制出的一种改良幽门螺杆菌抗原检测试剂盒(胶体金法)检测粪便幽门螺杆菌抗原,以~(13) C-UBT检测结果为诊断H.pylori感染的"金标准",并将两者进行对比研究,所有检测结果均拍照存档,采用随机、双盲和双验证法,以期客观真实地评价改良幽门螺杆菌抗原检测试剂盒检测粪便幽门螺杆菌的效果。结果改良幽门螺杆菌抗原检测试剂盒检测HpSA敏感度为90.48%,特异度为90.00%,Youden指数为80.48%,Kappa值为0.799;HpSA检测ROC曲线下面积为0.902±0.027,与完全无诊断价值的机会线下面积0.50相比,差异有统计学意义(P=0.000);Spearman相关系数r=0.800,P=0.000。结论改良幽门螺杆菌抗原检测试剂盒能准确检测H.pylori感染,其操作简便,可作为非侵入性诊断H.pylori感染筛查以及流行病调查的一种方法,将来有望成为患者家庭自查幽门螺杆菌的一种方法。  相似文献   

6.
儿童再发性腹痛中幽门螺杆菌不同检测方法   总被引:4,自引:0,他引:4  
目的 评价幽门螺杆菌(H.pylori)的不同检测方法及H.pylori感染在儿童再发性腹痛(RAP)诊断中的应用.方法 对在我院诊治的儿童RAP 72例,分为学龄期组24例,少年组48例,同时进行细菌培养、快速尿素酶试验、病理组织学检查、血清学H.pylori抗体检测和粪便H.pylori抗原(HpSA)检测.将前3项检查中2项阳性或细菌培养一项阳性作为诊断H.pylori感染的金标准.结果 金标准诊断H.pylori感染,阳性占37例,阴性占35例,总阳性率为51.4%;学龄期儿童组H.pylori检出阳性率为37.5%,少年组H.pylori检出阳性率为58.3%,两组比较差异有显著性(P<0.01);比较6种不同检测方法的敏感性、特异性、准确性,经x2检验,差异均无显著性(P>0.10).结论 H.pylori感染与儿童RAP之间存在一定的联系,少年组H.pylori感染率高于学龄期儿童组,而粪便HpSA检测有较高的敏感性和特异性,是一种简便可靠,非侵入性的诊断H.pylori感染的方法,尤其适合儿童.  相似文献   

7.
正幽门螺杆菌(Helicobacter pylori,H.pylori)与慢性胃炎、消化性溃疡、胃癌及胃黏膜相关淋巴组织(MALT)淋巴瘤的发生发展密切相关。1994年幽门螺杆菌被世界卫生组织列为胃癌发生的I类致癌因子,胃癌发生与幽门螺杆菌感染密切相关,根除幽门螺杆菌可降低胃癌的发生率。中国是幽门螺杆菌高感染率国家,同时也是胃癌高发国家,幽门螺杆菌感染不仅是一个临床问题,更是一个公  相似文献   

8.
幽门螺杆菌(helicobacter pylori,H.pylori,HP)感染是一个世界性问题。人类感染Hp可导致慢性胃炎、胃和十二指肠溃疡、消化性胃黏膜相关的淋巴样组织淋巴瘤和胃腺癌。根除幽门螺杆菌对胃肠疾病的转归和预防有着重要作用。但是由于抗茵药物的滥用,使得对幽门螺杆茵的治疗变得棘手。本文就Hp的致病机制、耐药性问题及治疗方法等的研究进展作一综述。  相似文献   

9.
目的:探讨COX-2和MMP-9在胃癌组织中的表达及其与幽门螺杆菌感染和胃部转移侵袭的关系.方法:采用快速尿素酶试验及Warthin-Starry银染色法检测45例胃癌标本中幽门螺杆菌感染情况,采用免疫组织化学法检测COX-2和MMP-9在胃癌组织中的表达,对其与幽门螺杆菌感染和胃癌患者临床病理特征的相关性进行分析.结果:①幽门螺杆菌感染组胃癌中浆膜侵袭和淋巴结转移卒均高于无幽门螺杆菌感染组(P<0.05).②胃癌浆膜侵袭组和淋巴结转移组中COX-2、MMP-9蛋白表达阳性率均分别显著高于无胃癌浆膜侵袭组、淋巴结转移组(P<0.05).③幽门螺杆菌感染与COX-2和MMP-9表达具有相关性.结论:幽门 螺杆菌感染能够增加胃癌的侵袭转移能力,其机制可能与COX-2和MMP-9表达增加有关.  相似文献   

10.
幽门螺杆菌是一种具有高感染率的慢性致病菌,它的感染能够引起消化性溃疡和胃癌等多种疾病。目前,传统的三联疗法对幽门螺杆菌的根除率不断下降,且副作用越来越多,而益生菌联合三联疗法的治疗方法已被许多临床试验证明能够解决传统三联疗法不能解决的问题。本研究探讨了益生菌在治疗幽门螺杆菌感染中的作用以及存在的问题,并对此治疗方法的发展做了简要的总结。  相似文献   

11.
Systematic significance of mature embryo of bamboos   总被引:1,自引:0,他引:1  
The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.  相似文献   

12.
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.  相似文献   

13.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.  相似文献   

14.
Intracellular cysteine aspartate-specific proteases (caspases) play both signaling and effector roles in realizing the program of cell death. Caspases function as proteolytic cascades unique for each cell type and signal triggering apoptosis. All parts of the proteolytic cascades are duplicated and controlled by feedback signals. Amplification cycles between pairs of caspases (the third and the sixth, the ninth and the third, the twelfth and the sixth, and others) help multiply the initial apoptotic signal. The presence of physiological inhibitors of apoptosis that directly interact with caspases creates a multilevel regulatory network of apoptosis in cell. The caspase proteolytic cascades are also regulated by sphingolipid secondary messengers, among them ceramide, sphingosine, and their phosphates. Moreover, an association of the caspase signaling with ubiquitin-dependent proteolysis is shown in cells. In particular, the use of extracellular activators and inhibitors of caspases allows irreversible activation of apoptosis in tumor cells or the prevention of apoptosis in cortical neurons under neurodegenerative diseases.  相似文献   

15.
The Drosophila Pax6 homolog twin of eyeless (toy) is so far the first zygotically expressed gene involved in eye morphogenesis in Drosophila. The study of its expression during embryogenesis is therefore informative of the initial events of eye development in Drosophila. We have analyzed how the initial expression domain of toy at cellular blastoderm is regulated. We show that the three maternal patterning systems active in the cephalic region (the anterior, terminal and dorsal-ventral systems) cooperate with zygotically activated gap genes to shape the initial expression domain of toy. Whereas Bicoid, Dorsal and Torso signaling synergistically act as activators, Hunchback, Knirps and Decapentaplegic act as repressors.  相似文献   

16.
Sixteen new species are proposed in the generaAckermania, Dressleria, Epidendrum, Maxillaria, Oncidium, Rodriguezia, Sigmatostalix, andTrigonidium. All new species are illustrated.Maxillaria vittariifolia L. O. Williams is newly recorded for Peru. A key is provided forTrigonidium of Peru.Trigonidium loretoense Schltr. andT. peruvianum Schltr. are lectotypified.  相似文献   

17.
Twenty three species in 11 genera were examined in the field to determine hosts. OnlyStriga asiatica andSeymeria cassioides have a narrow host range being restricted to grasses and pines, respectively. These are the only species which cause pronounced and sometimes serious host damage. The other species attach to a great diversity of hosts.  相似文献   

18.
李腾  唐启明  韦玉梅  赵建成  李敏 《广西植物》2021,41(8):1372-1390
通过对采自广西24个县(市)的1 147份青藓科植物标本的逐一鉴定及相关文献的查阅,确认有广西青藓科植物11属、44种,其中包括广西青藓科植物新记录属1属,即拟异叶藓属(Pseudokindbergia),新记录种7种,分别为匐枝青藓(Brachythecium procumbens)、阔叶尖喙藓(Oxyrrhynchium latifolium)、泛生尖喙藓(O. vagans)、拟异叶藓(Pseudokindbergia dumosa)、华东细喙藓(Rhynchostegiella sinensis)、长肋拟青藓(Sciurohypnum populeum)和弯叶拟青藓(S. reflexum)。该文提供了修订后的广西青藓科植物名录,并对其中的新记录属、种的主要形态学识别特征、生境和地理分布等进行了详细描述。  相似文献   

19.
Resin glycosides are secondary metabolites exclusive to the convolvulaceous plants. In this study, crypthophilic acids A–C (13), the first resin glycosides occurring in another family (Scrophulariaceae), and the other constituents of Scrophularia cryptophila were examined for in vitro antiprotozoal and antimycobacterial potentials. Except for crypthophilic acid B (2), all tested compounds exhibited growth-inhibitory effect against Trypanosoma brucei rhodesiense, with l-tryptophan (6) and buddlejasaponin III (7) being the most potent ones (IC50's 4.1 and 9.7 μg/ml). In contrast, the activity towards Trypanosoma cruzi was poor, and only crypthophilic acid C (3), 6 and 7 were trypanocidal at concentrations above 40 μg/ml. With the exception of 2 and 6, all compounds were active against Leishmania donovani. Harpagide (4) and 3 emerged as the best leishmanicidal agents (IC50's 2.0 and 5.8 μg/ml). Only compounds 3, 6 and 7 showed antimalarial activity against Plasmodium falciparum with IC50 values of 4.2, 16.6 and 22.4 μg/ml. Overall the best and broadest spectrum activity was presented by compounds 3 and 7, as they inhibited all four parasitic protozoa. None of the isolates had significant activity against Mycobacterium tuberculosis (MICs >100 μg/ml) or were toxic towards mammalian (L6) cells. This is the first report of antiprotozoal activity for natural resin glycosides, as well as for harpagide (4), acetylharpagide (5), tryptophan (6) and buddlejasaponin III (7).  相似文献   

20.
Three remarkable new genera of conidial lichen-forming fungi, with pycnidial or acervular conidiomata are described and illustrated.Hastifera tenuispora gen. et spec. nov. from the South-Tyrol, Italy, is characterized by very long and narrow hyaline conidia produced in pycnidial conidiomata immersed in thalline warts.Lichingoldia gyalectiformis gen. et spec. nov. from rocks subject to inundation by freshwater in Norway has long sigmoidly curved conidia which appear to be adapted to dispersal in water.Woessia fusarioides gen. et spec. nov. from aQuercus stump in the Burgenland, Austria, has a finely granular thallus and disc-like conidiomata producing falcate conidia; this species is also of interest in that it hasChlorella as the photobiont. The recently described hyphomyceteCheiromycina flabelliformis B. Sutton is reported from Austria for the first time, and is also lichenized. Recent collections ofNigropuncta rugulosa D. Hawksw. from Austria and Italy also show that this species is lichenized rather than parasymbiotic. In all five cases the fungal hyphae of the conidiogenous structures are continuous with those in intimate contact with cells of the algal partners and the biological relationship appears to be mutualistic giving rise to stable crustose lichen thalli.  相似文献   

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