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1.
酯酶试验与聚合酶链反应鉴别中间普氏菌的比较研究   总被引:1,自引:0,他引:1  
目的 研究脂酶试验和常规生化方法与聚合酶链反应比较在鉴别中间普氏菌Pi中的敏感度和特异度。方法 对207株牙周临床分离的产黑色素G厌氧杆菌分别进行脂酶试验、常规生化法鉴定和16srRNA特异引物PCR鉴定。结果 207株实验菌中PCR鉴定出Pi97株,脂酶试验检测出Pi126株,其中有85株PCR阳性,其敏感度为87.6%,特异度为63.7%。常规生化方法和脂酶试验共同鉴定出Pi80株,其中有55株PCR为阳性,其敏感度为67%,特异度为86.4%。结论 脂酶与常规生化方法对Pi的鉴别能力低于PCR( P<0.05),尚不能作为Pi菌种的可靠鉴定方法。  相似文献   

2.
Six laboratory methods were compared for isolating acid-fast bacteria. Tuberculous lymph nodes from each of 48 swine as identified by federal meat inspectors were processed by each of the methods. Treated tissue suspensions were inoculated onto each of eight media which were observed at 7-day intervals for 9 weeks. There were no statistically significant differences between the number of Mycobacterium avium complex bacteria isolated by each of the six methods. Rapid tissue preparation methods involving treatment with 2% sodium hydroxide or treatment with 0.2% zephiran required only one-third to one-fourth the processing time as a standard method. There were small differences in the amount of contamination among the six methods, but no detectable differences in the time of first appearance of M. avium complex colonies.  相似文献   

3.
Pyörälä S 《Theriogenology》1989,31(5):1067-1073
The relative accuracy of two pregnancy testing methods for swine were compared in a field study. The procedures used were manual palpation and amplitude-depth ultrasonic scanning. A total of 369 sows were examined by both methods. Seven additional gilts were examined by ultrasound only and 46 sows by palpation per rectum only. The number of correct positive and negative diagnoses made by both methods were calculated, and determination of accuracy as well as comparison between the tests were made on this basis. The relative accuracy was 97.6% for the manual method and 96.8% for the ultrasound method. Both tests had a high sensitivity, 99.2 and 98.9%, respectively. The ability of the tests to detect the non-pregnant animals was not as high, which is reflected by a lower specificity. No significant differences were noted between the two methods. A lower specificity and a lower negative predictive value were provided by ultrasound scanning as compared with those acquired by manual palpation. Both procedures were considered to be quick and convenient to perform. It was concluded that in spite of the new pregnancy testing methods introduced in the swine industry, manual palpation remains the most practical in terms of its accuracy, ease, and the minimal requirement for equipment. In gilts, palpation is unsuitable and ultrasonography currently remains the best choice for the diagnosis of pregnancy.  相似文献   

4.
Two methods are described for direct molar-mass measurement of low-molar-mass fragments obtained by oxidative cleavage of the capsular polysaccharide ofHaemophilus influenzaetype b. Absolute molar masses were determined by size-exclusion chromatography (SEC) with detection by multiangle laserlight-scattering photometry (MALLS) and differential refractometry (RI). The end-group structure of the polysaccharide fragments allowed the direct measurement of average chain length by quantitative1H NMR, from which molar masses were derived. Variation between the molar masses obtained by the two methods ranged from 5 to 7%. When molar masses estimated by indirect methods were compared to SEC-MALLS/RI data, significant deviations were observed. Analysis by SEC with secondary calibration with dextran standards gave molar masses that exceeded the SEC-MALLS/RI data by as much as 2.5-fold. Molar masses estimated by a combination of colorimetric assays varied from the SEC-MALLS/RI data by as much as 50%. These results demonstrated the applicability and superior accuracy of the direct methods of molar-mass determination of the polysaccharide fragments.  相似文献   

5.
Immunoblotting techniques are widely used for detection of antigen immobilized on nitrocellulose membranes. There are many immunolabeling methods and staining methods available to disclose the presence of antigen in such techniques. Five common staining methods each for alkaline phosphatase and horseradish peroxidase were examined. The staining methods with the highest sensitivity and the lowest background were selected for studies comparing five immunological labeling methods using human IgG as a model antigen. Results were evaluated on the basis of the least amount of detectable antigen and background staining. The most sensitive dot-blot method was then tested for its applicability to Western blots. For both dot-blots and Western blots, the immunoalkaline phosphatase methods are more sensitive than the corresponding immunoperoxidase methods. The use of biotinylated secondary antibodies and an avidin-enzyme conjugate is recommended. Disclosure of alkaline phosphate is best achieved with naphthol AS phosphate as substrate and fast blue BB as chromogen. Peroxidase is best stained using H2O2 and diaminobenzidine (DAB). Potential endogenous enzyme activities are demonstrable by blotting methods but can be inhibited by including levamisole in the disclosure reaction medium for calf intestinal alkaline phosphatase indicators, or by incubation of blots with sodium azide and hydrogen peroxide before immunolabeling when using horseradish peroxidase indicators.  相似文献   

6.
L T Yam 《Acta cytologica》1989,33(4):505-510
Immunocytochemical studies were performed on fine needle aspirates of the liver in a patient with hepatocellular carcinoma. A panel of commercially available antibodies was used to study the aspirated cells by immunoalkaline phosphatase and immunoperoxidase methods. The malignant cells in the aspirates, which were positively stained by the immunoperoxidase method for alphafetoprotein and by both methods for epithelial membrane antigen, were most probably hepatocellular in origin. Some cells were shown by the immunoalkaline phosphatase method to possess leukocyte-common antigen (LCA) and antigens of colonic and ovarian tissues. These findings were further investigated, and it was found that the tumor cells indeed had LCA as well as levamisole-resistant alkaline phosphatase activity. Although the immunoalkaline phosphatase methods are useful immunodiagnostic techniques applicable to fine needle aspirates, the endogenous enzyme activity present in some nonhematopoietic tumor cells is a cause for caution in the use of these methods in aspirates from nonhematopoietic tumor tissues.  相似文献   

7.
The sensory data from three different methods, multidimensional sorting, similarity scaling, and free-choice profiling were compared using ten commercial grape jellies as a model system. Without any prior training, the overall similarities/dissimilarities between stimuli were judged using both multidimensional sorting and pair-wise scaling and the sensory attributes were rated using free-choice profiling by different panels. A two-dimensional stimulus configuration best represented the data from each of the three methods. The underlying dimensions of stimulus space were identified from free-choice profiling data and also explained some background variables. The texture, sweetness, sourness, grape flavor and color contributed to both dimensions. All three methods were very similar in describing the most important differences among stimuli as suggested by the highly significant correlation between their first dimensions. The Procrustes analysis coupled with permutation tests, as well as RV coefficient, indicated that similarity scaling and free-choice profiling reached maximum consensus, whereas multidimensional sorting shared slightly lesser consensus with the other two methods.  相似文献   

8.
New computation methods for removing saccades in analysis of smooth pursuit eye movement characteristics were developed. They have removed saccades more completely than previous methods, and were very effective especially for noisy data recorded by the EOG method. The fully developed method was applicable to eye movement data in tracking of pseudo-random target movement as well as deterministic target movement. Furthermore, the methods were also useful for extracting the number and magnitudes of saccades more precisely.  相似文献   

9.
Summary The compositions of fifty-nine common histological dyes, as well as duplicate samples of several dyes from different suppliers, have been studied by agar gel electrophoresis, agarose gel electrophoresis, paper electrophoresis, paper chromatography and thin layer chromatography. Tables are presented to show the number of components present in each dye as disclosed by the different methods; the cases where duplicate samples were available are summarised in a separate table.On the basis of effectiveness and convenience agar gel electrophoresis and thin layer chromatography were by far the best methods. The Chromatographic method was of slightly wider applicability but as electrophoretic methods gave information on dye charge, agar gel electrophoresis was the best single method.  相似文献   

10.
We have validated and compared two direct methods for the determination of fatty acids in feces by capillary gas chromatography. Method I consisted of esterification of fatty acids using acetyl chloride. Method II used boron trifluoride-methanol as esterification reagent. The two methods were assayed with and without previous freeze-drying of the fecal sample. We found that the two methods could be carried out without sample freeze-drying. Precision and recovery rates were determined and the results were satisfactory. Both methods gave similar results, but Method II has certain advantages over Method I, such as speed, safety, and better recovery rates.  相似文献   

11.
The estimation of iron requirements is crucial for nutrition and food policy. The traditional methods for estimating iron requirements are balance methods based on iron intakes and excretions and factorial methods based on estimated iron absorption rates and estimated iron losses from body compartments. As an alternative, numerical methods for estimating iron requirements from population data of iron status were developed. The iron status data reported by Satoh (1991) were used in the sixth edition of Recommended Dietary Allowances for Japanese. The menstrual iron losses in Japanese premenopausal women were estimated from the literature to calculate total iron losses as the sum of basal iron losses and menstrual iron losses. The use of this alternative method is illustrated by analyzing the same population data comprising the prevalence of iron deficiency and the distribution of iron intake. The estimated average requirements were affected by the form of distribution function, the relative standard deviation of requirements, and the correlation coefficient between iron intakes and requirements. We conclude that numerical methods can be very useful for estimating iron requirements and to elucidate dietary recommendations of iron. These methods may contribute to determining requirements of other nutrients as well as iron.  相似文献   

12.
Two new methods for coliphage detection, a colorimetric agar-based (CAB) method and a liquid colorimetric presence-absence (LCPA) method, were compared to the coliphage method proposed by the American Public Health Association (APHA; Standard Methods for the Examination of Water and Wastewater, 18th ed., American Public Health Association, Washington, D.C., 1992). Both new methods are based on the induction of β-galactosidase in Escherichia coli and the release of the enzyme through a lytic cell infection. The released enzyme then cleaves a chromogenic substrate which produces a colored reaction product. Ninety split water samples from four different sources were tested. A total of 52 samples were positive by the CAB method, 52 were positive by the LCPA method, and 53 were positive by the APHA method. Results indicated that (i) the CAB and LCPA methods were as sensitive in coliphage detection as the APHA method, (ii) both the CAB and LCPA methods were easier to read and interpret than the APHA method, and (iii) the CAB method detected more coliphages in a positive sample than the APHA method in two of the four types of water sources. Importantly, the rapid and simple LCPA method was as reliable and sensitive as either of the two agar-based methods in coliphage detection.  相似文献   

13.
干、湿化学法在乳糜血中的应用比较   总被引:2,自引:0,他引:2  
目的探讨乳糜血对干、湿化学法检测结果的影响,以期找到一种适合于在乳糜血中应用的检测方法。方法分别用干、湿化学法检测乳糜血中总蛋白、血糖,比较两种方法检测结果差异。结果湿化学法测定结果高于乙醇处理法(P0.05),干化学法与乙醇处理法结果比较差异无显著性(P0.05)。结论在乳糜血检测中干性化学法与湿性化学法比较更接近真实值。  相似文献   

14.
Various methods were used in the treatment of 451 patients with verruca plantaris who were observed for a period of nine months after treatment. Results obtained by the various methods were as follows:[Formula: see text]  相似文献   

15.
Various methods were used in the treatment of 451 patients with verruca plantaris who were observed for a period of nine months after treatment. Results obtained by the various methods were as follows:[FORMULA: see text]  相似文献   

16.
线虫作为土壤健康指示生物的方法及应用   总被引:32,自引:2,他引:32  
简述了线虫作为土壤健康指示生物的优势,归纳了常用指数和分析方法,对成熟指数及基于营养类群的一些指数和分析方法进行了详细介绍.与其他指数相比,成熟指数更能敏感地反映土壤环境的受胁迫程度,基于营养类群的指数和分析方法可以在生态系统功能水平上更好地揭示土壤环境的健康状态.概述了以上指数和方法在农业、森林、草原及其他生态系统中的应用研究.结合目前存在的一些问题,提出以下建议:加强对土壤线虫生活史和食性等特性的认识;进一步完善现有指数,将多种指数和分析方法结合使用;加强土壤线虫在多种生态系统及大尺度地域空间内的应用.  相似文献   

17.
The aim of this study was to evaluate the accuracy of cefoxitin disc diffusion as a prediction of oxacillin resistance in coagulase-negative staphylococci (CoNS), and also to compare genotypic and phenotypic methods for detecting this resistance property. A total of 151 clinical CoNS isolates were tested by PCR for the presence of the mecA gene (gold standard method). The isolate susceptibilities were determined by the disc diffusion method with oxacillin (1 microg) and cefoxitin (30 microg) and by the agar dilution method for cefoxitin and oxacillin. Although none of the techniques showed 100% sensitivity and 100% specificity, the cefoxitin disc diffusion and oxacillin agar dilution were the best methods for detecting resistance to oxacillin among CoNS as these methods produced the best negative and positive predictive values. A combination of methods can be used routinely to identify resistance to oxacillin in CoNS.  相似文献   

18.
水稻遗传转化研究进展   总被引:5,自引:0,他引:5  
水稻遗传转化的主要方法,包括农杆菌介导法,基因枪法,电激法,PEG法等,论述了用于水稻转化的各种外植体,影响水稻遗传转化和植株分化的各种因素,各种标记基因及相应的选择方法和外源基因在转基因水稻中的遗传规律,比较了常用启动子在水稻中的表达强度,一些已转移到优良水稻品种中的有益农艺性状基因,如抗病、抗虫、抗除草剂等,介绍了它们在水稻品种改良中所发挥的作用。  相似文献   

19.
Summary To enhance the efficiency and specificity of diamine methods in light microscopy, these methods were sensitized by sliver enhancement in combination with trichloro(ethylene) platinate (KTP). The sensitized diamine methods consisted of a diamine (high or low iron diamine: HID or LID), KTP, borohydride reduction (BH) and a physical development (PD) sequence. The new methods have been successfully applied to routinely prepared tissue sections obtained from rat organs, such as salivary glands, stomach, colon, kidney, lung and trachea. In the tissues subjected to the sensitized diamine methods, weakly diamine-stained histological structures exhibited vivid positive reactions. The combined sensitized diamine methods and selective procedures, such as enzyme digestion and chemical modification, have substantiated that these methods were of sufficient efficiency and specificity.  相似文献   

20.
The application of sensory methodology for measuring deodorizing effect of an air conditioner equipped with electric plasma was introduced. Deodorizing effect was measured using chemical and sensory methods at different time (0, 30 and 60 min) and mode (control, blowing and cooling) of an air conditioner. Smoke from a roll of cigarette in a closed room was used as a source of odor and the concentrations of acetic acid and ammonia were measured as odorous chemical components. As one of the sensory methods triangle test was used and as a first step to obtain deodorizing effects by triangle test, the threshold of each panelist was obtained as the log dilution ratio of odor concentration at which the difference from odorless air was detected. The odor concentration at each time and mode was calculated using the threshold of the panel and the deodorizing effect was obtained on the basis of the odor concentration. In addition to a triangle test, scaling methods such as category scaling or magnitude estimation were used to measure deodorizing effect of an air conditioner. Deodorizing effects by scaling methods were calculated based on odor intensity with time at each mode. The regression analysis was done between the efficacy of deodorizing effect by sensory test and those by acetic acid and ammonia, the R2 values of the regression equations for triangle test, category scale, and magnitude estimation were 0.84, 0.72 and 0.69, respectively. Deodorizing effect by triangle test explained the decrease of acetic acid and ammonia better than those by category scaling or magnitude estimation while high cost and time consuming labor involved in triangle tests reduced the merit. The results of this study demonstrated that various sensory methods could be used to measure deodorizing effect of air conditioners and further researches on fast and reliable methods are needed to establish the official procedures.  相似文献   

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