首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A study of the incidence of Cryptococcus neoformans in Alicante was carried out in environmental samples from the cities of Alicante and Santa Pola. The samples were pigeons faeces and Eucalyptus camaldulensis tissues. This study shows that the prevalence of the yeast in faeces from captive pigeons is higher (81.5%) than in the same samples from urban pigeons (16.3%). Regarding the biotype and varieties, a 79.3% of the isolates belonged to C. neoformans, and all of them were C. neoformans var. neoformans. None of the E. camaldulensis samples showed C. neoformans growth, although some Cryptococcus laurentii strains were isolated from flowers.  相似文献   

2.
AIMS: To determine the numbers of Escherichia coli O157 present in the faeces of naturally infected cattle. METHODS AND RESULTS: A combination of the most probable number (MPN) technique and automated immunomagnetic separation (AIMS) was used to enumerate E. coli O157 in cattle faeces from both pasture-fed and grain-fed animals. A total of 22 E. coli O157 positive faecal samples were enumerated for E. coli O157 (10 from pasture-fed and 12 from grain-fed animals). The numbers of E. coli O157 in cattle faeces varied from undetectable (<3 MPN g-1 of faeces) to 2.4 x 104 MPN g-1. There was no significant difference (P = 0.06) between the numbers of E. coli O157 in pasture-fed or grain-fed cattle faeces, although the geometric mean (antilog of the mean of log10 transformed MPN values) was higher in grain-fed (130 MPN g-1) than in pasture-fed (13 MPN g-1). CONCLUSIONS: Although the number of samples tested is small, the results indicate that E. coli O157 make up a small proportion of the total E. coli population present in cattle faeces. SIGNIFICANCE AND IMPACT OF THE STUDY: Information on the numbers of E. coli O157 present in cattle will assist in developing more robust quantitative risk assessments and formulating intervention strategies.  相似文献   

3.
本文应用悉生小鼠做模型,研究了大肠杆菌(E.coli)和青春型双歧杆菌(Bifidobacterium adolescentis)对艰难梭菌(Clostridium diffi-cile)的拮抗作用。E.coli和B.adolescentis预先接种无菌SSB小鼠,再用C.difficile攻击。结果表明,E.coli和E.coli B.adolescentis对小鼠均有保护作用,保护平分别为87.5%(7/8)和100%(8/8)。B.adolescentis定值后数量达10~(10.28)CFU/g,且对E.coli数量和小鼠本身无影响。E.coli和B.adolescentis联合比E.coli单独抑制C.difficile在肠道中繁殖的作用更强(0.02>P>0.01),但对其毒素产生和粘附力的作用无明显差异。C.difficile攻击后的1~14天,小鼠粪便中C.difficile菌数在10~4至10~8CFU/g内变化,细胞毒素为10~3CFU/g,A毒素滴度为10~2/g,B.adolescentis也一度下降10~2CFU/g。接种C.difficile后,小鼠虽无明显的腹泻症状,但组织学仍可观察到肠粘膜有充血和分泌增加等轻度损害。扫描电镜和普通光镜均发现E.coli单独或与B.adolescentis共同吸附在肠粘膜微绒毛表面,未见有C.difficile吸附。  相似文献   

4.
Plasma carcinoembryonic antigen (C.E.A.) levels in inpatients proved at necropsy to be cancer free were used to assess the ability of the C.E.A. assay to distinguish benign and malignant disease. The patients had a mean C.E.A. level significantly greater than that for young healthy people. In view of the considerable overlap of the ranges of plasma C.E.A. concentration in cancer patients and patients with non-malignant disease a probabilistic interpretation is advocated rather than the use of a simple cut-off between positive and negative. On the basis of the cancer-free control group, 19 out of 64 untreated patients with various solid tumours had plasma C.E.A. levels considered to correspond to a greater than 95% probability of cancer.  相似文献   

5.
宫颈癌是妇科常见的恶性肿瘤,特定型别的人 乳头瘤病毒(HPV)感染是引发宫颈癌的主要因 素。根据HPV致癌性的不同可分为高危型,低 危型。Munoz N[2]等对来自9个国家的1918例宫 颈癌组织进行各型HPV筛查,最终确认HPV-16、 18、26、31、33、35、39、45、51、52、53、56、58、59、66、 68、73及82型为高危型。李洁等[3]用核酸印迹技 术对1986至1994年间来自我国14个省市自治区 的1008宫颈癌组织进行HPV型别检测,发现 HPV-16、18、31、35、51、58等型的存在,并发现各 地区主要流行型别随地理位置有所差异。  相似文献   

6.
Twenty-four (82.7%) out of 29 patients suffering from hospital acquired urinary infections by Klebsiella pneumoniae had the same species in their faeces. Biotyping of 24 urinary and 219 fecal strains of K. pneumoniae resulted in 50 different biotypes - an average of four biotypes per fecal sample. Ten patients (34.4%) had the same biotype in urine and faeces without any correlation with previous vesical catheterization (p greater than 0.05). Using resistotyping to four chemical compounds selected among 34 tested substances (brilliant green, malachite green, potassium tellurite and mercuric chloride) 16 different resistotypes were found. Fourteen patients (58.3%) presented the same resistotype in urine and faeces but only in five patients was there correlation with simultaneous biotyping identity. Simultaneous occurrence of identical biotypes or resistotypes in faeces and urine occurred in only 54.2% of cases. However, there was a significant association between resistance ot mercuric and tellurite ions in fecal and urinary strains isolated from the same patient (p less than 0.001).  相似文献   

7.
Intravenous infusions of 14C-testosterone (Te) either alone or in combination with 3H-estradiol (E2) were given to five normal male subjects, twelve male patients on haemodialysis (HD) treatment and to one patient with a very restricted renal function. The elimination of radioactivity was measured in urine, HD fluid and faeces. Urinary excretion diminished with renal function. It was negligible at a creatinine clearance of less than one ml per minute. A quarter of both isotopes was eliminated by six HD treatments within three weeks. No difference was found in this respect between nephrectomized patients and those who were still in possession of their kidneys. The main excretion occurred in the stools. E2 metabolites, and to a lesser extent Te metabolites, appeared in the faeces within 24 hours, which might be explained by biliary excretion only. More 3H (E2 metabolites) than 14C (Te metabolites) was found in the faeces; more 14C than 3H found in HD fluid.  相似文献   

8.
Aims: Development of a novel inoculation technique to improve the current methods of determining the leaching of Escherichia coli O157:H7 from faeces. Methods and Results: Ruminant faeces were inoculated with a high [c. 107 colony forming units (CFU) g−1] or low (c. 104 CFU g−1) load of a lux-marked strain of E. coli O157:H7 via injection, and subjected to four simulated heavy rainfall events. The population density and metabolic activity of E. coli O157:H7 recovered within the leachate was determined following each simulated rain event and compared with the indigenous E. coli population. The concentration of E. coli O157:H7 in the leachates followed a similar trend to that of nonpathogenic E. coli. Significantly greater densities of generic and pathogenic E. coli were recovered in the leachates generated from sheep faeces compared with cattle faeces. Pathogen metabolic activity was also significantly greater in sheep faeces. Conclusions: Our findings show that E. coli O157:H7 may readily leach from ruminant faeces during rain events. The bacterium leaches more freely from sheep faeces than from cattle faeces and displays greater metabolic activity within sheep leachate. Significance and Impact of the Study: A novel inoculation technique was developed that allowed the determination of both population density and cellular activity of E. coli O157:H7 in leachate derived from faeces.  相似文献   

9.
AIM: To develop and validate a direct plating method applicable to epidemiological studies for enumerating Escherichia coli O157 in cattle faeces. METHODS AND RESULTS: The spiral plate count method was used to enumerate E. coli O157 in faecal samples. The accuracy and variation of counts was then assessed using faecal samples inoculated with E. coli O157. There was good agreement between inoculated levels of E. coli O157 and those recovered from faeces, particularly when counts were > 10(2) CFU g(-1) of faeces. The method was applied to a small study assessing short-term survival of E. coli O157 in naturally infected cattle faeces. E. coli O157 was found to survive in faeces for over 10 days at concentrations above 10(3) CFU g(-1) of faeces. Populations of E. coli O157 were also found to increase 100-fold in the first few hours after defecation. CONCLUSIONS: The enumeration method is easy to implement and enables a quick throughput of large numbers of samples. The method is accurate and reliable and enables the inherent variation in count data to be explored but needs to be used in combination with a more sensitive method for samples containing < 10(2) CFU g(-1) of faeces. SIGNIFICANCE AND IMPACT OF THE STUDY: The method described is appropriate for enumeration of E. coli O157 in cattle faeces in large-scale epidemiological studies.  相似文献   

10.
Seven groups of three sheep were given pelleted diets as follows: A, 97% hay + 3% molasses; B, C, D, 82% hay + 3% molasses + 15% dried pig faeces; E, F, G, 67% hay + 3% molasses + 30% dried pig faeces. In an attempt to counteract potential toxic effects of copper in the pig faeces (613 mg/kg dry matter), molybdenum was added to diets C and F at the rate of 90 mg/kg diet, and to diets D and G at the rate of 175 mg/kg diet. Sulphate was included in all diets at the rate of 1.08% of diet. Measurements were made of digestibility, copper retention, and plasma glutamic oxaloacetic transaminase (GOT) values during a 70-day feeding period, after which the animals were slaughtered.Dry matter digestibility coefficients were : diet A, 49.2; diets B, C, D, 44.4; diets E, F, G, 42.5, from which the coefficient for pig faeces alone is calculated to be < 30. Mean copper retention over the 70 days ranged from 210 mg for diet A to 1225 mg for diet G (excluding diet E which showed an aberrant retention of 53 ± 185 mg). Plasma GOT values fluctuated between diets and between sheep with a maximum value of 182 units/ml. Mean liver copper concentrations ranged from 718 mg/kg dry matter for diet A to 1740 mg/kg for diet E. Necrotic lesions occurred in some livers. Kidneys were apparently normal. There were no clear differences in copper status of animals receiving 15% versus 30% pig faeces except for a tendency for liver damage to be greater in the latter. There were no apparent effects of additions of molybdenum.The pig faeces were poorly utilized and, because of the high copper content, potentially hazardous to the health of the sheep.  相似文献   

11.
AIMS: To evaluate the numbers and selected phenotypic and genotypic characteristics of the faecal indicator bacteria Escherichia coli and enterococci in gull faeces at representative Great Lakes swimming beaches in the United States. METHODS AND RESULTS: E. coli and enterococci were enumerated in gull faeces by membrane filtration. E. coli genotypes (rep-PCR genomic profiles) and E. coli (Vitek GNI+) and enterococci (API rapid ID 32 Strep and resistance to streptomycin, gentamicin, vancomycin, tetracycline and ampicillin) phenotypes were determined for isolates obtained from gull faeces both early and late in the swimming season. Identical E. coli genotypes were obtained only from single gull faecal samples but most faecal samples yielded more than one genotype (median of eight genotypes for samples with 10 isolates). E. coli isolates from the same site that clustered at >/=85% similarity were from the same sampling date and shared phenotypic characteristics, and at this similarity level there was population overlap between the two geographically isolated beach sites. Enterococcus API(R) profiles varied with sampling date. Gull enterococci displayed wide variation in antibiotic resistance patterns, and high-level resistance to some antibiotics. CONCLUSIONS: Gull faeces could be a major contributor of E. coli (10(5)-10(9) CFU g(-1)) and enterococci (10(4)-10(8) CFU g(-)1) to Great Lakes recreational waters. E. coli and enterococci in gull faeces are highly variable with respect to their genotypic and phenotypic characteristics and may exhibit temporal or geographic trends in these features. SIGNIFICANCE AND IMPACT OF THE STUDY: The high degree of variation in genotypic or phenotypic characteristics of E. coli or enterococci populations within gull hosts will require extensive sampling for adequate characterization, and will influence methods that use these characteristics to determine faecal contamination sources for recreational waters.  相似文献   

12.
AIMS: To monitor the decay of E. coli O157 in soil (loamy sand) on a scout campsite following an outbreak in humans. METHODS AND RESULTS: Samples of soil and sheep faeces were collected from the campsite and tested for the presence of E. coli O157 by immunomagnetic separation (IMS) after enrichment in buffered peptone water + vancomycin at 42 degrees C for 6 h. Enumeration of target was carried out by direct plating onto sorbitol MacConkey agar plates supplemented with cefixime and tellurite (CTSMAC) incubated at 37 degrees C for 24 h. Low numbers (< 100 g(-1)) were estimated by the most probable number (3-tube MPN) technique. CONCLUSIONS: Survival was observed for 15 weeks. SIGNIFICANCE AND IMPACT OF THE STUDY: A number of laboratory studies have followed the decay of E. coli O157 in soil, animal faeces and water. This study follows (for the first time) the decay of the organism in soil after an outbreak associated with sheep. It demonstrates the long-term persistence of the organism in the environment and the results will be potentially important in performing risk assessments for both human and animal infection.  相似文献   

13.
A combination of reversed-phase high-performance liquid chromatography (RP-HPLC) and capillary zone electrophoresis (CZE) was used for characterization of α-chymotryptic digests of human pepsinogen A, human pepsinogen C (both isolated from stomach mucosa of patients suffering from gastric cancer), swine pepsinogen and their dephosphorylated forms. Combining RP-HPLC and CZE for peptide mapping allowed to detect phosphorylations in molecules of the above mentioned gastric zymogens. We have found one phosphate group in the molecule of human pepsinogen A and two phosphate groups in the molecule of human pepsinogen C. The investigated sample was obtained from stomach mucosa of a patient suffering from gastric cancer. An increased number of phosphate groups in molecules of human pepsinogen seems to be associated with gastric cancer. The developed method represent a suitable tool for studying relationships between specific phosphorylations of proteins and cancerogenesis or potentially could serve for early diagnosis of gastric cancer.  相似文献   

14.
Mice were infected experimentally and subclinically with Corynebacterium kutscheri to recover the organism from mice faeces. The faeces were then cultured using selective furazolidone-nalidixic acid-colimycin agar. The number of C. kutscheri per gram of fresh faeces varied from mouse to mouse, but once established in the intestine, the organism was excreted in the faeces for at least five months. Viable bacteria were detected in most of the faecal samples, including those stored in the animal room for five days. The number of organisms in the stored faeces decreased gradually but did not differ significantly from those in the fresh faeces until they had been stored for more than three days. Many infected mice excreted between 10(4.77) and 10(5.37) colony forming units (CFU) of C. kutscheri per day in their faeces, and one mouse even excreted 10(3.74) CFU at eight weeks postinfection. These values showed little daily variation. Our present study showed that subclinically infected mice discharged the organism continuously and persistently in their faeces. Therefore, faecal samples would be useful for monitoring infection with C. kutscheri in living mice in a manner that is not stressful for the animals.  相似文献   

15.
熊光武  袁杨  李萌  郭红燕  张小为 《遗传》2010,32(4):339-347
为检测HPV16上游调控序列(Upstream regulatory region, URR)、E6、E7癌基因变异在北京地区宫颈癌患者癌组织中的分布特征, 探讨该地区宫颈癌发生同HPV16变异株间的相关性, 文章以提取的31例HPV16检测阳性宫颈癌组织DNA为模板, 设计针对性引物扩增URR、E6、E7 3个目的片段, PCR产物直接测序并通过GenBank对比分析变异和分支鉴定情况。在所分析的宫颈癌组织中, URR是突变频率最高的片段, 其次为E7, 最保守的序列为E6。共发现热突变位点8个, 分别为URR序列上G7521A(100%)、C7435G(96.77%)、C24T(45.16%)、A7729C(45.16%)、G7839A(45.16%); E6序列上T178G(41.94%); E7序列上A647G(45.16%)、T846C(45.16%)。HPV16分支分布频率最广的是As型(54.84%), 其次为E型(45.16%)。研究结果提示, HPV16URR序列上G7521A、A7729C、G7839A, E6序列上T178G、T350G, E7序列上A647G、G658A等位点的变异可能与病毒致癌潜能及宫颈癌的发生相关。北京地区宫颈癌患者中As和E型可能是两种最主要的HPV16分支, 这有可能会为HPV疫苗的研制和感染治疗提供有价值的信息。As型和E型病毒在不同年龄组和不同肿瘤分期组的患者中分布频率有差异, 这可能会为揭示宫颈癌年轻化趋势提供新的线索。  相似文献   

16.
Cattle and sheep are major reservoirs of Escherichia coli O157 and consequently these and certain other farm animals can pass out large numbers of this organism in their faeces. Thus the ability of the organism to survive in faeces, on pastureland and in associated water systems has important implications for its spread to crops by direct application of manure, by irrigation with infected water or directly to man by contact with animals or contaminated soil. Model systems were used to determine the persistence of the organism in river water, cattle faeces, soil cores and on stainless steel work surfaces. Survival of the organism was found to be greatest in soil cores containing rooted grass. Under these conditions viable numbers were shown to decline from approximately 10(8) g(-1) soil to between 10(6) and 10(7) g(-1) soil after 130 d. When the organism was inoculated into cattle faeces it remained detectable at high levels for more than 50 d. In contrast the organism survived much less readily in cattle slurry and river water where it fell in numbers from more than 10(6) ml(-1) to undetectable levels in 10 and 27 d, respectively. The survival of E. coli O157 was also investigated on stainless steel surfaces, where as air-dried deposits, it was shown to survive for periods in excess of 60 d. It was most stable at chill temperatures (4 degrees C) and viability was only partially reduced at 18 degrees C. In addition to stainless steel, the organism was shown to survive for extended periods on domestic (plastic) cutting boards, both at room and chill temperatures. Sanitizing agents, such as hypochlorites and a compound comprising both cationic and anionic-based active ingredients were found to be effective in killing various VTEC on stainless steel surfaces.  相似文献   

17.
本文报告不同来源大肠杆菌对不同红血球的血凝反应。使用Evans法,磷酸盐缓冲液琼脂在4℃环境中操作可获满意的结果。人粪源大肠杆菌与豚鼠红血球的MRHA为27.3%,而尿源菌株仅2.7%。人和猪粪源大肠杆菌对A型红血球的MRHA为0~4%,而人尿源株为41.3%。尿源菌株对P_2~K血球MRHA为41.3%,对血球为12%。尿源菌株对A型与P_2~K型红血球的MRHA相符率达97%,扫描电镜显示具有菌毛的细菌粘附于A型红血球表面,A型红血球可取代罕有的P_2~K血球作血凝试验以诊断尿道致病性大肠杆菌。  相似文献   

18.
Griffiths NJ  Walton JR  Edwards GB 《Anaerobe》1997,3(2-3):121-125
Equine anterior enteritis is an acute syndrome with unknown aetiology, although salmonellosis and infection with Clostridium perfringens have both been suggested as potential causes. The main aim of this preliminary study was to compare the prevalence of toxigenic types of C. perfringens in clinically healthy horses and in horses with anterior enteritis. From horses admitted with colic at Phillip Leverhulme Large Animal Hospital in 1995-1996, samples of gastric reflux, small intestinal contents and faeces were taken for isolation of C. perfringens. Five of those horses were admitted as anterior enteritis cases, of which C. perfringens was isolated in pure culture in all five horses. Two of the anterior enteritis cases from which viable bacterial counts had been performed revealed 10(6) CFU/g faeces C. perfringens. Samples of gastric reflux and small intestinal contents submitted from one of these horses revealed 10(4) CFU/mL and 10(5) CFU/mL respectively. The number of C. perfringens observed in the gastric reflux was considered significant as the total volume removed was 12 L. The counts observed in faeces taken from horses admitted with anterior enteritis, were significantly higher than the <10(2) CFU/g faeces observed in faeces from healthy horses and horse presenting with colic and with other diagnoses. The major toxigenic types of C. perfringens in both healthy and diseased horses are being investigated using the polymerase chain reaction (PCR) to amplify target DNA sequences of the toxin genes. Primers have been designed from the published DNA sequences of the enterotoxin, alpha, beta, epsilon and iota toxin genes. PCR products obtained from NCTC strains of C. perfringens have been cloned and the sequenced, to verify that the amplicon sequence is correct. Initial typing suggests that C. perfringens type A is the predominant toxin type isolated from healthy horses and horses with colic with other diagnoses.C. perfringens strains isolated from horses with anterior enteritis are of type D.  相似文献   

19.
By selective culture campylobacters (C jejuni and C coli) were isolated from the faeces of 57 (7-1%) out of 803 unselected patients with diarrhoea; none were isolated from 194 people who had not got diarrhoea. Specific agglutinins were found in the sera of 31 out of 38 patients with campylobacter enteritis and 10 of them had a rising titre. Half the patients were aged 15 to 44 years, but the incidence was highest in young children. All the patients with campylobacters had a distinctive clinical illness with severe abdominal pain. Campylobacters are a relatively unrecognised cause of acute enteritis, but these findings suggest that they may be a common cause. Spread of infection was observed within 12 out of 29 households, and in these cases children were usually implicated. Several patients were apparently infected from chickens, both live and dressed, and poultry may be the primary source of the organism. In two cases dogs with diarrhoea were found to be infected with strains indistinguishable from their human contacts. Ten patients acquired their infections while travelling abroad.  相似文献   

20.
Lymphocytes from patients with multiple sclerosis are sensitized to carcinoembryonic antigen (C.E.A.) in almost the same degree as are those from subjects with cancer. During pregnancy and the early puerperium there is an even higher degree of cellular sensitization to C.E.A. Patients with neurological diseases other than multiple sclerosis also show significant sensitization to C.E.A. though of less degree than do those with multiple sclerosis. Sensitization to C.E.A. is thus not specifically characteristic of cancer. The unexpected sensitization in multiple sclerosis may be associated with the pronounced degree of gliosis found in that condition.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号