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1.
We have isolated and developed 180 new polymorphic chicken microsatellite markers. In addition, primers have been developed for 91 microsatellites derived from the GenBank sequence database (isolated by the laboratory of Terry Burke, Leicester University), of which 89 were polymorphic, and six existing polymorphic markers (HUJ) have been modified. The primer sequences were designed to allow optimal performance of the markers, in sets containing multiple microsatellites, on ABI sequencers. The average number of alleles for the 275 polymorphic markers described was 4.0. Of these markers, 93% were polymorphic in the Wageningen resource population whereas 57% of the markers were polymorphic in the East Lansing reference population and only 44% could be mapped in the Compton reference population. The microsatellite markers described in this paper, in combination with the microsatellite markers published previously, are particularly well suited for performing a total genome scan for the detection of quantitative trait loci (QTL).  相似文献   

2.
An automated fluorescence-based PCR system (a model AG-9600 AmpliSensor analyzer) was investigated to determine whether it could detect Shiga toxin-producing Escherichia coli (STEC). The AmpliSensor PCR assay involves amplification-mediated disruption of a fluorogenic DNA signal duplex (AmpliSensor) that is homologous to conserved target sequences in a 323-bp amplified fragment of Shiga toxin genes stx1, stx2, and stxe. Using the Amplisensor assay, we detected 113 strains of STEC belonging to 50 different serotypes, while 18 strains of non-Shiga-toxin-producing E. coli and 68 strains of other bacteria were not detected. The detection limits of the assay were less than 1 to 5 CFU per PCR mixture when pure cultures of five reference strains were used and 3 CFU per 25 g of food when spiked ground beef samples that were preenriched overnight were used. The performance of the assay was also evaluated by using 53 naturally contaminated meat samples and 48 raw milk samples. Thirty-two STEC-positive samples that were confirmed to be positive by the culture assay were found to be positive when the AmpliSensor assay was used. Nine samples that were found to be positive when the PCR assay was used were culture negative. The system described here is an automated PCR-based system that can be used for detection of all serotypes of STEC in food or clinical samples.  相似文献   

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Modified MicroScan gram-positive MIC no. 8 panels (PM-8) were analyzed for their improved ability to detect vancomycin resistance (VR) and high-level aminoglycoside resistance (HLAR) in enterococci. A validation study design that utilized selected challenge strains, recent clinical isolates, and reproducibility experiments in a multicenter format was selected. Three independent medical centers compared the commercial panels to reference broth microdilution panels (RBM) and Synergy Quad Agar (QA). Resistance was verified by demonstration of VR and HLAR genes by PCR tests. The study was conducted in three phases. (i) In the challenge phase (CP), two well-characterized sets of enterococci were obtained from the Centers for Disease Control and Prevention; one set contained 50 isolates for VR testing and one contained 48 isolates for HLAR testing. In addition, a set of 47 well-characterized isolates representing diverse geographic areas, obtained from earlier national surveillance studies, was tested at the University of Iowa College of Medicine (UICM). (ii) In the efficacy phase (EP), each laboratory tested 50 recent, unique clinical isolates by all methods. (iii) In the reproducibility Phase (RP), each laboratory tested the same 10 strains by all methods in triplicate on three separate days. All isolates from the EP were sent to the UICM for molecular characterization of vanA, -B, -C1, -C2-3, and HLAR genes. In the CP, the ranking of test methods by error rates (in parentheses; very major and major errors combined, versus PCR results) were as follows: for high-level streptomycin resistance (HLSR), QA (12.0%) > PM-8 (5.2%) > RBM (1.6%); for high-level gentamicin resistance (HLGR), RBM (3.7%) > PM-8 (3.1%) > QA (2.6%); and for VR, RBM = QA (3.0%) > PM-8 (1.2%). In the EP, agreement between all methods and the reference PCR result was 98.0% for HLSR, 99.3% for HLGR, and 98. 6% for VR. In the RP, the percentages of results +/- 1 log2 dilution of the all-participant mode were as follows: for VR, 100% (PM-8), 98.9% (QA), and 90.0% (RBM); for HLSR, 99.6% (RBM), 98.5% (PM-8), and 82.2% (QA); and for HLGR, 99.6% (RBM), 99.3% (PM-8), and 98.1% (QA). The ability of the PM-8 to detect VR and HLAR in enterococci was comparable to those for reference susceptibility and molecular PCR methods and was considered acceptable for routine clinical laboratory use.  相似文献   

7.
The authors evaluate the combination of three drugs, vinorelbine, ifosfamide, and cisplatin, which have been shown to produce good response rates and a significant gain in survival when any two of them are given together. Seventy-seven untreated patients with inoperable stage III-IV non-small-cell lung cancer from three centers were included. The combination consisted of cisplatin 30 mg/m2 daily, ifosfamide 1,500 mg/m2 daily, mesna 1,500 mg/m2 daily on days 1-3, and vinorelbine 25 mg/m2 daily on days 1 and 8. Four cycles were administered every 4 weeks for a total of 267 cycles, before an assessment for toxicity, effective dose intensity, response rate, and survival was made. Toxicity was mainly hematologic (grade 3-4 neutropenia (15.7%), anemia (8.2%), and thrombopenia (2.6%)) but did not require granulocyte colony-stimulating factors. Objective response rate was 41.1% (95% confidence interval, 29.5-52.9%) in 68 patients suitable for assessment. The mean time to progression and median survival were 7.7 +/- 1.3 months and 11.6 months, respectively. One-year survival was 47.1%. The effective dose intensity of cisplatin and ifosfamide correlated strongly with survival, whereas stage and performance status did not. This study confirms previously reported favorable results for response and survival rates obtained in stage III-IV non-small-cell lung cancer with the vinorelbine, ifosfamide, and cisplatin combination. Respect of a scheduled dose intensity has a clear-cut influence on survival and should be evaluated routinely in future polychemotherapy trials.  相似文献   

8.
BACKGROUND: Because of serious adverse effects of centrally acting antitussive agents, is necessary to find new drugs with cough-suppressing activity. Medicinal herbs are a potential source of polysaccharides with high antitussive efficiency and on the other with minimal side effects. AIM: The study was to assess the antitussive action of mixture of a polysaccharides (RL) and polysaccharide-xylan (XY), both isolated from above-ground parts of Rudbeckie fulgida var. sullivantii. The observed activity was compared to those of narcotic and nonnarcotic antitussive substances used in clinical practice. METHODS: Cough was evoked by mechanical irritation of the airways in nonanaesthetized cats with chronic tracheal cannuly. The plant substances were administered perorally in the dose of 50 mg per kg body weight. RESULTS: Results indicate, that administration of RL induced a suppression of the followed cough parameters from both areas of airways (total fall in cough parameters by 46.6%). Administration of xylan induced the fall in the followed cough parameters with more significant influence on the laryngopharyngeal area of the airways (total fall in cough parameters 48.2%). CONCLUSION: Administration of RL and xylan did not achieve the effect of codeine, but had a more intensive antitussive effect than the peripherally acting droprozine and prenoxdiazine. (Fig. 3, Ref. 11.)  相似文献   

9.
Primers were designed to amplify sequences of verocytotoxin genes and eaeA genes of Escherichia coli O26:H11, O111:H8, and O157:H7 in a multiplex PCR assay. This assay successfully detected E. coli O26:H11 in bloody stool specimens in which other enteric pathogens were not detected by culture-based methods. Rapid assays to detect non-O157:H7 verocytotoxin-producing E. coli is important to improve methods for the etiologic diagnosis of hemorrhagic colitis.  相似文献   

10.
Bipolar affective disorder (BP) is a major neuropsychiatric disorder with high heritability and complex inheritance. Previously reported linkage between BP and DNA markers in the pericentromeric region of chromosome 18, with a parent-of-origin effect (linkage was present in pedigrees with paternal transmission and absent in pedigrees with exclusive maternal inheritance), has been a focus of interest in human genetics. We reexamined the evidence in one of the largest samples reported to date (1,013 genotyped individuals in 53 unilineal multiplex pedigrees), using 10 highly polymorphic markers and a range of parametric and nonparametric analyses. There was no evidence for significant linkage between BP and chromosome 18 pericentromeric markers in the sample as a whole, nor was there evidence for significant parent-of-origin effect (pedigrees with paternal transmission were not differentially linked to the implicated chromosomal region). Two-point LOD scores and single-locus sib-pair results gave some support for suggestive linkage, but this was not substantiated by multilocus analysis, and the results were further tempered by multiple test effects. We conclude that there is no compelling evidence for linkage between BP and chromosome 18 pericentromeric markers in this sample.  相似文献   

11.
In this report the authors describe the use of continuous venovenous hemodialysis (CVVHD) in a medically unstable patient who suffered from a spontaneous cerebellar hemorrhage. Conventional dialysis techniques carry the risk of developing the dialysis disequilibrium syndrome (DDS) when performed in the presence of a variety of intracranial diseases. The CVVHD technique was used successfully in a morbidly obese, short-statured woman with a spontaneous hypertensive intraparenchymal cerebellar hemorrhage. The woman experienced acute renal failure several days after her hemorrhage and her general medical condition prevented her from undergoing surgical evacuation. The CVVHD did not result in elevations in intracranial pressure (ICP) and the patient made a full recovery from both acute renal failure and life-threatening posterior fossa hemorrhage. This case is noteworthy because of the absence of abnormally high ICP elevations or development of DDS in a patient with a large acute posterior fossa intraparenchymal brain hemorrhage and acute renal failure whose case was managed with CVVHD in the acute period.  相似文献   

12.
In this work we introduce the confluent and various sizes image analysis method (COVASIAM), an automated colony count technique that uses digital imaging technology for detection and separation of confluent microbial colonies and colonies of various sizes growing on petri dishes. The proposed method takes advantage of the optical properties of the surfaces of most microbial colonies. Colonies in the petri dish are epi-illuminated in order to direct the reflection of concentrated light coming from a halogen lamp towards an image-sensing device. In conjunction, a multilevel threshold algorithm is proposed for colony separation and counting. These procedures improved the quantification of colonies showing confluence or differences in size. We tested COVASIAM with a sample set of microorganisms that form colonies with contrasting physical properties: Saccharomyces cerevisiae, Aspergillus nidulans, Escherichia coli, Azotobacter vinelandii, Pseudomonas aeruginosa, and Rhizobium etli. These physical properties range from smooth to hairy, from bright to opaque, and from high to low convexities. COVASIAM estimated an average of 95.47% (sigma = 8.55%) of the manually counted colonies, while an automated method based on a single-threshold segmentation procedure estimated an average of 76% (sigma = 16.27) of the manually counted colonies. This method can be easily transposed to almost every image-processing analyzer since the procedures to compile it are generically standard.  相似文献   

13.
We evaluated the effects of the thyroid hormone on bone and mineral metabolism in rats using biochemical markers [pyridinoline (Pyr), deoxypyridinoline (Dpyr), Osteocalcin (OC), alkaline phosphatase (Alp)] and the measuring of bone mineral density (BMD). First, the rats were divided into three groups: 1) control group 2) The fifty micrograms group (T3-50) [It was given 50 micrograms/kg ip/day of triiod-l-thyronine (T3) for 2 weeks.] 3)The hundred micrograms group (T3-100) [It was given 100 micrograms/kg ip/day of T3 for 2 weeks.] Next, the rats were divided into two groups: 1)control group and 2)T3 group. The latter was given 100 micrograms/kg of T3 ip/day for 4 weeks. In experiment 1, Pyr and Dpyr levels in the T3 groups were significantly higher or well tended to be higher than those in the control group. OC levels in the T3 groups were significantly higher than in the control group until day 7. The Z-score of Pyr and Dpyr in T3-100 were two to thirteen times higher than those of OC and Alp. In experiment 2, Pyr and Dpyr levels in the T3 group were significantly higher or well tended to be higher than those in the control group. OC levels in the T3 group were significantly higher than those in the control group only on day 3. In the present study, the administering of T3 100 micrograms decreased both cortical (tibia) and trabecular (lumbar spine) BMDs in the rats. Bone resorption continued to increase after increased bone formation was reduced by T3 administration. Furthermore, bone resorption exceeded bone formation throughout T3 administration.  相似文献   

14.
The AG-9600 AmpliSensor Analyzer is an automated fluorescence-based system for detection of polymerase chain reaction (PCR) products. The principle of the AmpliSensor PCR assay involves amplification-mediated disruption of a fluorogenic DNA signal duplex (AmpliSensor) that is homologous to a target sequence within a 284-bp amplified fragment of the Salmonella invA gene. Since the assay is homogenous, the data can be obtained by direct measurement of fluorescence of the amplification mixture. The accumulation of the amplified product, reflected by the fluorescence index, is monitored cycle by cycle by the AG-9600 Analyzer. The detection limit of the assay was less than 2 colony-forming units (cfu) per PCR reaction using a pure culture of Salmonella typhimurium. In post-spiking experiments in which Salmonella was added to the overnight pre-enriched samples (chicken carcass rinses, ground beef, ground pork and raw milk), the detection limit of the assay was 2-6 cfu per PCR reaction. In pre-spiking experiments in which Salmonella was added to the samples prior to overnight pre-enrichment, the detection limit was less than 3 cfu per 25 g or 25 ml of food. The assay was up to 2 orders of magnitude more sensitive than detection by ethidium bromide-stained agarose gel electrophoresis. To further evaluate assay performance, 54 naturally contaminated chicken carcass rinses, 65 raw milk and six ground pork samples were tested in the study. Thirty-eight Salmonella-positive samples confirmed by the Modified Semi-solid Rappaport-Vassiliadis (MSRV) culture assay were found positive using the AmpliSensor assay. Two chicken carcass rinses found positive using the assay were MSRV-negative. In addition, relative quantification using the AmpliSensor assay was linear up to 3 logs of initial target concentration in artificially contaminated food samples.  相似文献   

15.
Diagnosis of giardiasis relies largely on the microscopical detection of trophozoites or cysts in feces. However, this method is labour- and time-intensive and depends highly on the skill of an experienced microscopist. In order to identify the prevalence of Giardia lamblia in travellers returning from overseas, we evaluated sensitivity and specificity of a commercially available ELISA kit for the detection of Giardia-lamblia-antigen in stool. Nine hundred seventy-eight stool samples from 795 patients were examined by microscopy (iron-hematoxyilin-stain, SAF-concentration) and ELISA. Altogether, Giardia infection could be detected in 74 subjects. On evaluation of all samples, the ELISA turned out to be more sensitive than microscopy (95.5% vs. 81.8%) and 99.7% specific for Giardia lamblia. Especially with microscopy, the examination of more than one stool specimen did improve diagnostic sensitivity. It seems therefore advisable to retain the practise of examining at least three stool samples before considering a patient as not infected. The coproantigen-ELISA is especially advantageous in situations where only a single stool sample can be examined. It should not, however, replace microscopical examination of stool specimens for ova and parasites since other potential pathogens would otherwise escape detection.  相似文献   

16.
A solid phase fluorescence-based immunoassay was developed for the detection of Escherichia coli O157:H7 using an antigen down competition format. A soft glass capillary tube served as the solid support, to which heat-killed E. coli O157:H7 were adsorbed. Polyclonal anti-E. coli O157:H7 antibody, conjugated with biotin, was used and the bound antigen-antibody complex was detected using avidin molecules labelled with Cy5, a fluorescent cyanine dye. Any E. coli O157:H7 in the sample would compete with the formation of this complex, reducing fluorescence. This assay was tested for sensitivity with spiked ground beef and apple cider samples. The minimum detectable number of cells present in the initial inoculum was calculated to be approximately 1 colony-forming unit (cfu) per 10 g of ground beef when samples were enriched in modified EC broth for 7 h at 37 degrees C. The minimum detectable number of cells for the apple cider samples was calculated to be approximately 0.5 cfu ml-1. The E. coli cells in the cider samples were captured with immunomagnetic beads, incubated for 7 h in the enrichment broth, and detected with the solid phase fluorescence immunoassay.  相似文献   

17.
目的:建立一种快速、特异、灵敏的幽门螺杆菌检测方法,并对方法进行评价,为快速、准确、有效检测幽门螺杆菌方法的建立提供依据.方法:以尿素酶基因序列为靶位点,用Primer Express 3.0软件设计引物及探针,经Blast软件对相似序列搜索后,筛选出一套最优与常见致病菌无交叉反应的引物;分别用食品中常见致病菌大肠杆菌、金黄色葡萄球菌、单增李斯特菌、沙门菌和空肠弯曲菌DNA进行特异性实验;将计数过的幽门螺杆菌菌悬液与牛奶样品混合液,梯度稀释后分别提取DNA进行荧光PCR扩增,确定检测方法的灵敏度;对人工污染幽门螺杆菌的生奶及生肉样品进行检测验证方法的可行性.结果:利用尿素酶基因设计的引物及探针仅对幽门螺杆菌有扩增曲线,而其他对照以及阴性对照均未有明显扩增曲线;能够对生奶及生肉中污染的幽门螺杆菌进行有效扩增;设计的引物对幽门螺杆菌的检测敏感性可达到3 CFU·mL-1,检测可以在4 d内完成.结论:荧光PCR方法特异性强,灵敏度高,可以快速、准确检测食品中污染的幽门螺杆菌.  相似文献   

18.
The process of alerting child custody and access litigants to the purposes, procedures, and ramifications of the child custody or parenting examination invokes both psychological and legal considerations. A full and complete notification of purpose can be accomplished only by a coordinated effort between the examiner and counsel. In light of the range of potential variations in examiner approach, this notification may be individualized to reflect the examiner's style and the case needs. Because of the abundance of information to be included and the importance of the inclusion of counsel in the process, written notification, provided in advance of the examination, is useful. The basic elements of a notification are discussed, to be adapted to the parameters of the examiner's practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
The restriction fragment length polymorphism of c-Ha-ras-1 and L-myc genes and expression of cell surface effector molecules were studied to determine their potential utility as markers for assessing risk of metastasis in 84 lung cancer patients. We performed a comparative study of primary lung carcinomas, metastases, adjacent tissues and blood samples in a group of patients with lung cancer of different histological types, grade of differentiation and presence of regional and distant metastasis. No differences in the frequency of c-Ha-ras-1 rare alleles were found between lung cancer patients and unaffected controls. The detection of common a4-allele seems to be associated with metastasis and low differentiation of lung carcinomas. S-allele of L-myc was observed in 82.6% of patients with metastatic lesions. Homozygosity of L-allele patients was not evidence for distant metastasis and only 17.4% of these patients have metastatic lesions of the lymph nodes. The expression of HLA class I and receptor of transferrin (TrRec) were tested immunohistochemically in the same patients. In the group of squamous cell carcinomas with regional metastases the expression of HLA class I antigens was decreased [7/21 (33.3%) positive staining tumors versus 13/20 (65.0%) in the group without metastases]. The opposite situation was observed for TrRec. The data of restriction fragment length polymorphism of oncogenes and expression of two cell surface effector molecules, identified in the same patients, were combined. The registration of more than one poor marker, tested in individuals with squamous cell carcinoma, closely correlated with dissemination and advanced stage of the disease. Nearly 90% (20/22) of patients with well and moderately differentiated tumor revealed metastatic lesions versus 6.6% (1/15) of patients with manifestation of a single poor marker. Finally, proposals could be made for the development of a risk group that incorporates both clinical and molecular biology features in the prediction of metastasis.  相似文献   

20.
We developed an immunochromatographic whole-blood test (WBT) which detects antibodies to human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) from fingerstick blood. The sensitivity and specificity of the WBT were 99.41% (1,018 confirmed positive patients) and 99.89% (941 uninfected patients), respectively (enzyme immunoassay [EIA] on serum or plasma as a reference). WBT performance was comparable to those of licensed EIAs and Western blotting, using 18 HIV-2 sera, 23 HIV-1 seroconversion panels, and a low-titer performance panel (in lieu of whole blood).  相似文献   

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