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At least 793 records · Page 44Linked to original sources
PubMed1982

[Combined use of microbiological methods for the intraspecific differentiation of Shigella sonnei. The use of the S. sonnei phage typing method in the People's Republic of Bulgaria].

The data on the use of the method for S. sonnei phage typing in Bulgaria during the period of 1973-1980 were analyzed. The comparative study with the use of two sets of phages (international and Bulgarian) were carried out. 9360 S. sonnei strains isolated in various districts of the country, mainly during epidemic outbreaks, were subjected to phage typing. 31 phage types corresponding to the international scheme were revealed; of these, 15 phage types could be subdivided into phage subtypes by means of Bulgarian phages. In systematic epidemiological study the combined use of both the sets of phages was shown to enhance the effectiveness of the method. The necessity of using, simultaneously with phage typing, the methods of biotyping, colicin and antibiotic typing, as well as the method of studying the properties of R-plasmids, is emphasized. This is based on the established correlation between different types and phage type changes occurring due to the action of R-plasmids.

Bacteriophage Typing↗
PubMed1982

Comparison of a rapid micromedia method to cystine trypticase agar (CTA) and fluorescent methods for the identification of pathogenic Neisseria.

A four-hour micromedia method which detects enzymes formed by bacteria for the degradion of carbohydrates was compared to the utilization of carbohydrates was compared to the utilization of carbohydrates in cystine tyrpticase agar (CTA) for the identification of Neisseria gonorrhoeae and Neisseria meningitidis. This rapid micromedia method (RMM) correlated 100% with the utilization of carbohydrates in CTA. Identification of N. gonorrhoeae by RMM was compared to the identification achieved by a commercially available coagglutination method and a fluorescent antibody (FA) technique. Of 144 isolates identified as N. gonorrhoeae by RMM, 122 (84.7%) were identified by coagglutination and 141 (97.9%) were identified by FA as N. gonorrhoeae. Five (13%) of 40 isolates identified as N. meningitidis by RMM were identified as N. gonorrhoeae by coagglutination while eleven (28%) were identified as N. gonorrhoeae by the FA technique. One (14%) and four (57%) of seven isolates identified as Neisseria species were identified as N. gonorrhoeae by coagglutination and the FA technique respectively. The rapid micromedia method was found to be a quick, sensitive, specific and economic way of identifying N. gonorrhoeae and N. meningitidis.

Cheilitis↗
PubMed1980

[A comparative study of the white cell pipette method and the Makler counting chamber method of counting spermatozoa].

A new method for counting spermatozoa was introduced by Makler. This method was compared with the white blood cell pipette method and the results revealed high precision and accuracy (difference of means = 5,9%). Makler's method, which is very simple to perform, has the advantage that rapid and reliable sperm counts can be done. Therefore, the Makler counting chamber can be used with confidence in the performance of semen analysis by any doctor or in any laboratory.

Humans↗
PubMed1980

Evaluation of methods for quantitating erythrocyte antibodies and description of a new method using horseradish peroxidase-labelled antiglobulin.

Concentrates of anti-D and rabbit anti-human globulin (AHG) prepared by standard elution and ammonium sulphate precipitation methods were labelled with 125I and 131I and horseradish peroxidase (HRP), respectively. The number of anti-D molecules attached per rbc ranged from 12,500 to 21,300 for the various phenotypes studied and the label of D-negative rbc never exceeded 3.4% of these values. With 131I-AHG the uptake by control D-negative cells averaged 13% of the uptake by D-positive cells. It was also found that the average ratio of AHG molecules reacting with each IgG molecule was between 2.6 and 3.3 in free solution regardless of the label but was between 3.4 and 7.5 on rbc and ghosts with 131I-AHG and 3 or lower with HRP-AHG. A colorimetric procedure for quantitating IgG antibodies on rbc ghosts is described using HRP-labelled-AHG and o-dianisidine as the hydrogen donor. The method is very sensitive and useful for the detection of coating antibodies but cannot be used for precise quantitation because about 50% of the IgG molecules on rbc are lost in preparing the ghosts. An AutoAnalyzer method for estimating the number of antibodies attached to red cells is briefly described. Direct measurements of numbers of antigens receptors with radiolabeled specific antibodies gave the most reproducible results. Labelled rabbit AHG was not as good because the ratio of AHG to IgG varied. The AutoAnalyzer method may prove useful because of its convenience.

Antibodies↗
PubMed1980

[Binding capacity of albumin: comparison of the chromatographic method and electrophoretic method].

In the present study we intended to prove the reliability of the electrophoretic method proposed by Athanassiadis et al. [2] for the detection of the bilirubin binding capacity in the sera of icteric newborns, comparing it with the chromatographic method. 35 sera, in which the value of the bilirubin was included between 5 and 20 mg/dl, with a distribution of values of bilirubin binding capacity between 0 and 16 mg/dl, had been examined. The results obtained proved a perfect agreement between these two methods: the Authors prefer the electrophretic method, because it consents a more exact estimation of the bilirubin binding capacity of the serum.

Bilirubin↗
PubMed1980

A coupled-enzyme equilibrium method for measuring urea in serum: optimization and evaluation of the AACC study group on urea candidate reference method.

We describe a coupled-enzyme equilibrium method for measuring urea in serum, which is performed on supernates prepared by treating each specimen with Ba(OH)2 and ZnSO4 (Somogyi reagent). Analytical recovery of [14C]urea added to a variety of matrices was essentially complete (mean, 100.6%) for the supernates after precipitation. Nine variables were univariately examined in arriving at the reaction conditions for the method: glutamate dehydrogenase, urease, 2-oxoglutarate, ADP, Tris . HCI, NADH, EDTA, pH, and temperature. The reagent is stable for at least 48 days at--20 degrees C and for 23 days at 4 degrees C. Mean analytical recovery of urea (14 mmol/L) added to seven different specimens (three different matrices) was 100.8%. The analytical linear range of the method extends to 30 mmol of urea per liter. Of 22 potential interferents, only bilirubin at 1 mmol/L (580 mg/L), hemoglobin at 10 g/L, and hydroxyurea at 6 mmol/L showed more than 2% interference. We discuss precision and effects of specimen dilution, and compare results for 100 human serum specimens with those measured for the same specimens with four other urea methods. We examined the effects of measuring a blank, consisting of sample and reagent without urease, with each specimen.

Animals↗
PubMed1994

[A simple ELISA method for the detection of HBsAg: Organon Teknika HBsAg Uniform II screening and confirmation test. Comparative study using the HBsAg Hapanostika method. A multicenter study].

An one-step enzyme-linked immunoabsorbent method, named as HBsAg Uniform II has been described for the detection of serum HBsAg, and a comparison was made with a widely used ELISA technique HBsAg Hepanostika test, to evaluate sensitivity, specificity and reproducibility of the method. A total of 531 serum samples from patients with liver disease and with renal failure, as well as 1065 samples from blood donors have been investigated. While the sensitivity of Uniform II vs. Hepanostika was 99.5% vs. 72.7%, the specificity was 99.2% of both methods. The positive predictive values did not differ (99.5% vs. 99.2%), however, the negative predictive values were 99.2% vs. 71.7%, respectively, in favour of Uniform II test. The Uniform II confirmatory test confirmed the positive HBsAg results in 94%, this rate was 74% using Hepanostika system. The new method proved to be a simple, quick, reliable test, which can be useful as a valuable tool in both the clinical diagnosis and blood donor screening.

Blood Donors↗
PubMed1993

[Ligature and excision method with diathermy for haemorrhoidectomy: in comparison with conventional method].

The usefulness of ligature and excision method with diathermy (group D) for haemorrhoidectomy was evaluated in comparison with conventional ligature and excision method with scalpel and scissors (group S) from several parameters. Intraoperative bloodloss and hospitalization days in group D were significantly smaller than those in group S. Moreover, post-operative woundal bleeding and edema in group D were significantly smaller than those in group S. As regards post-operative pain, although there were no significant differences between the two groups, the values in group D were slightly improved as compared with group S. These results indicate the usefulness of diathermic method for haemorrhoidectomy because of its better cost-efficacy as compared with conventional method with scalpel and scissors.

Adult↗
PubMed1994

Numerical method for the interpolation of digitized lines (unrolling method).

The proposed method can be used for reconstructing, from n not necessarily equidistant points of a digitized polydrome line, a set of n1 equidistant points (with n1 > n) interpolating the original points. This method is based on a transformation of the original line into a digitized monodrome function D(1i) (unrolling function), where 1i is the line length between the origin and the ith point (i = 1,..., n1). Advantage of this method consists in reducing the two-dimensional interpolation problem to the one-dimensional field. In scintigraphic imaging, it is possible to achieve interpolation and coding of ROI's (Regions Of Interest) edges. For n samples of a monodrome line this method can also be applied, representing a possible alternative to splines. The numerical procedure is developed to reduce the noise on the points.

Heart↗
PubMedDate not supplied

Comparison of MICRO-ID Listeria method with conventional biochemical methods for identification of Listeria isolated from food and environmental samples: collaborative study.

Fourteen laboratories participated in a collaborative study to evaluate the ability of the MICRO-ID Listeria identification method to correctly identify Listeria isolated from food and environmental sources. Each collaborator received 60 isolates consisting of 51 Listeria and 9 non-Listeria cultures. All isolates were identified by conventional biochemical analyses in the principal laboratory. Cultures were checked for purity by Gram staining and examined for oxidase and catalase activities. Only Gram positive, oxidase negative, catalase positive cultures were tested with the method. Colonies from trypticase soy agar with 0.6% yeast extract were suspended in 4.6 mL physiological saline to a MacFarland No. 1 turbidity standard and used to inoculate the test strip. In addition, the hemolytic reaction of each isolate was determined by using the Christie-Atkins-Munch-Peterson (CAMP) test and by stabbing sheep blood agar. Identification of Listeria is based on the octal code obtained from the strip and the hemolytic reaction of the isolate. The MICRO-ID Listeria method agreed with conventinal biochemical identification for 98.0% of L. monocytogenes, 77.1% of L. seeligeri, 90.0% of L. ivanovii, 96.4% of L. grayi/L. murrayi, 73.9% of L. welshimeri, and 100% of L. innocua isolates. A large percentage of errors in identification of the L. seeligeri and L. ivanovii cultures was caused by inaccurate reading of the CAMP and hemolysis tests rather than errors in the test strip. The method was adopted first action by AOAC International.

Animals↗
PubMed1995

[A method of selective PCR-amplification of genomic DNA fragments (SAGF method)].

A method for separating into definite sets of a complex mixture of fragments obtained by DNA cleavage with IIS- or IIN-types of restriction endonucleases producing single-stranded termini of different sequences at the fragment ends has been developed. The method is based on the ligation of short double-stranded adapters with single-stranded termini complementary to the termini of a selected set of fragments followed by PCR-amplification with the primer which represents a strand of the adapters. Using endonucleases BcoKI and Bli7361 recognizing sequences CTCTTC and GGTCTC and producing three- and four-nucleotide 5'-termini, respectively, it has been shown that amplification of a set of fragments occurs only when the adapters are attached to DNA fragments with DNA-ligase. Several applications of the SAGF-method are suggested: for obtaining individual bands in DNA fingerprinting; for reducing the kinetic complexity of DNA in the representational difference analysis (RDA method) of complex genomes; for cataloguing DNA fragments, and for constructing physical genomic maps.

Animals↗
PubMed1995

A new Plaque Glycolysis and Regrowth Method (PGRM) for the in vivo determination of antimicrobial dentifrice/rinse efficacy towards the inhibition of plaque growth and metabolism--method development, validation and initial activity screens.

A new method, the Plaque Glycolysis and Regrowth Method (PGRM), is described for the evaluation of antimicrobial effects on plaque metabolism in vivo. The method relies on the experimental observation that in vivo sampled dental plaques, collected from different quadrants of the dentition, produce equivalent rates of metabolic activity and regrowth when similarly dispersed and normalized into incubation media. In applications of the technique to antimicrobial evaluations, overnight fasted dental plaque is collected from a non-treated quadrant of the dentition along the gingival margin. Topical formulations are used in vivo. Following this, dental plaques are collected from other dentition quadrants at extended times, allowing for the back diffusion, clearance and natural intraoral deactivation of antimicrobials within the oral cavity. In vivo treated and non-treated plaque samples are subsequently tested for metabolic and regrowth activity under controlled and standardized conditions in vitro following normalization for biomass. The technique thus combines the necessary biological factors important to the legitimate evaluation of antimicrobial effects in vivo, while benefiting from the improved precision and control provided by in vitro assessment of plaque activity. In this paper evidence is presented validating the PGRM method, and initial activity screens of commercial antimicrobial mouthrinses and toothpastes, including a new stabilized stannous fluoride dentifrice, are described.

Analysis of Variance↗
PubMedDate not supplied

Comparison of modified TECRA visual immunoassay with AOAC method 989.14 and reference culture methods 967.25-967.28 for detection of Salmonella in foods and related samples.

A validation study was conducted to compare a new modified version of the TECRA Salmonella Visual immunoassay (Mod. VIA) with the original immunoassay (AOAC Method 989.14) and the reference culture methods (967.25-967.28). The Mod. VIA was supplemented with polyclonal antibodies to Salmonella pullorum and S. gallinarum, and compared favorably with AOAC Method 989.14 in sensitivity, inclusivity, and exclusivity studies. The ability of the Mod. VIA to recover Salmonella from artificially contaminated samples was not significantly different from that of the reference method. It is recommended that the Mod. VIA be adopted as Official First Action.

Culture Media↗
PubMed1996

[Comparison of standard methods for determination of pseudocumene in urine using gas chromatography with the headspace technique and a new method using a headspace automatic sampler].

The biological indicators that have been proposed for monitoring occupational exposure are: concentration of the solvent or metabolized compounds in alveolar or expired air samples, in venous or arterial capillary blood samples and in urine samples. Recently, many researches have reported significant relationships between the time-weighted average exposure and the urinary concentrations for various solvents. The aim of our study was to compare two methods in which urinary concentrations of pseudocumene were determined by gas chromatography using headspace technique. The standard method was based on determining concentration of organic solvents in 100 mm3 or 1 cm3 samples of urine. The incubation conditions were as follows: equilibration temperature and time: 70 degrees C, 30 min., respectively. 1 cm3 of gas phase was sampled with a gas-tight syringe and injected into a gas chromatograph. The new method using Headspace Sampler was based on determining concentrations of solvents in 10 cm3 samples of urine. The operating conditions were: equilibration time 30 min.; equlibration temperature 80 degrees C; pressurization time 0.1 min.; loop fill time 0.1 min.; loop equilibration 0.1 min.; loop equilibration time 0.05 min.; inject time 1 min.; loop temperature 150 degrees C, transfer line temperature 150 degrees C. HP 7694 Headspace Sampler minimizes sample degradation with a chemically inert pathway extending from the sample loop to the column head. The analytical parameters of both methods (linearity, precision, reproducibility, stability and sensitivity) are fully compatible with the principles of biological monitoring. Application of the headspace autosampler eliminated interference from the biological matrix and made it possible to achieve very low detection limit.

Benzene Derivatives↗
PubMed1997

[A device in reconstruction method after distal subtotal gastrectomy: special reference to double tract method with jejunal pouch].

In the surgery of gastric cancer, it is necessary to consider not only the curability of gastric resection but also the quality of life of the patients in the choice of reconstruction method after distal gastrectomy. We have devised the jejunal pouch double tract method after gastrectomy. We reported in this study on the details of method and the satisfactory results. We employed 15 cases of gastric cancer which should be resected over three quarters of the stomach because the tumor occupation were in the middle third of the stomach and were expected long survival period. The operative procedure was as follows: (1) completion of gastric resection and lymph node dissection, (2) separation of jejunum at the site of 25 cm anal side from the Treitz's ligament, (3) pulling up the anal side of the jejunum preparing double jejunal pouch with approximately 10 cm in length using GIA, (4) anastomosis between residual stomach and jejunal pouch, (5) duodenojejunostomy at the site of 3-5 cm anal side from the pouch, (6) jejunojejunostomy at the site of 15 cm anal side from the duodenojejunostomy. Double tract reconstruction with jejunal pouch after distal gastrectomy is well-balanced method in the storage and discharging capacity, and useful in the view of better quality of life, especially in the cases which could be expected long survival period.

Anastomosis, Surgical↗
PubMed1997

Remarks on methods for estimating body composition parameters: reliability of skinfold and multiple frequency bioelectric impedance methods.

A sample of 104 adults underwent testing of body composition by multiple frequency bioelectric impedance analysis (MBIA) under controlled conditions, by anthropometric methods (skinfold thicknesses and BMI) and by the urinary creatinine method. The statistical comparison of body composition parameters (Fat, FFM, TBW), estimated by different methods for the same subjects, pointed out significant differences in mean values. The precision of skinfold and MBIA measurements was evaluated by a second control measurement. Concerning the MBIA, the reliability increased with increasing frequencies. Nevertheless, measurement reliability is higher for skinfolds than for MBIA. Under the condition that there is a real anthropometric technical ability, we affirm that the body composition parameters may at present be better estimated by the skinfold method.

Adult↗
PubMed1998

[Development of a method of studying actual nutrition according to analysis of the frequency of consumption of food products: creation of a questionnaire and general evaluation of the reliability of the method].

The method of actual feeding evaluation on frequency of food-stuffs consumption was developed. The method of 24-hour reproduction of a feed and the method of consumed food registration in a diary by testing person himself. The main results of study testified to reliability of data, received by a developed method.

Adult↗
PubMed1978

A new method for investigating the relation between change and initial value in longitudinal blood pressure data. I. Description and application of the method.

The relation between change and initial value is of great interest in longitudinal studies. With variables containing random errors (short-term intra-individual variations and measurement errors) the directly computed relation is however, biased by the regression towards the mean phenomenon. Earlier proposed solutions of the problem are unsatisfactory. In this paper the regression towards the mean phenomenon is described and a new method is proposed by which the error caused by the regression towards the mean is avoided. The method is applied to a set of longitudinal blood pressure data. It is shown that the observed, biased relation in this case is significantly negative, while the correct relation obtained with this method is significantly positive. Since random errors are present in most biological variables, similar erroneous conclusions may easily be drawn also in other cases if the regression towards the mean phenomenon is not corrected for. In this analysis, random errors constitute 65--80% of the observed blood pressure change. To reduce this dominance, recommendations about study design for future studies of change/initial value relationships are given.

Blood Pressure↗