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[Results of two methods for testing bacterial susceptibility to antibiotics: disk method and a new semi-automatic method in liquid medium (ABACR procedure) and comparison with the minimal inhibitory concentration (author's transl)].

A performance analysis was established between three methods for testing of bacterial susceptibility to sixteen antibiotics: agar dilution or minimal inhibitory concentration (MIC) method, agar diffusion or DISK method, and semi-automatic dilution in liquid medium or ABACR method. Precision of the three methods was determined using three reference strains in repetition experiments (9 repetitions for MIC, 60 repetitions for both DISK and ABAC). The results show that MIC method was the most precise, and that the precision of DISK and ABAC methods was not sifnificantly different. Fidelity of both DISK and ABAC methods was compared in taking as reference the MIC of 200 wild strains of Gram-negative bacteria. Omitting the data concerning trimethoprim-sulfamethozoaxol, the results were found concordant between DISK and MIC methods in 68.6 percent of the cases, between ABAC and MIC methods in 73.6 percent, and between ABAC and DISK methods in 68.9 percent. With regard to MIC, ABAC method gave results slightly better than those of DISK method, especially for five antibiotics: gentamicin, minocyclin, doxycylin, chloramphenicol and polymyxin B. So, the ABAC method looks very interesting for a semi-automatic routine method in testing bacterial susceptibility to antibiotics.

Anti-Bacterial Agents

[Comparison of two methods of antibiotic sensitivity tests: gel diffusion and automatic method using ABAC apparatus. I. Variation and dispersion of the two methods (author's transl)].

The authors studied comparatively the sensitivity of 3 bacterial strains (P. Aeruginosa and two E. coli) with regard to antibiotics using an automatic method (ABAC) compared with a gel diffusion technic with impregnated disks. Each strain was tested by both methods 50 to 55 times. The diffusion method was easily reproducible with an average standard deviation of 2.23 mm. Its results were in agreement compared with the average diameter of measurements in 93.3% of cases. The automatic method gave results which agreed together in 95.7% of cases. It is thus reproducible. If one compares it with the results of the diffusion method, considered here as the reference method, we obtained the same response in 86.3% of cases. In 13.7% there was disagreement in interpretation (in most cases, the strain found intermediate in gel diffusion was considered sensitive on autoanalysis).

Anti-Bacterial Agents

[Determination of Li, Na, K, Mg and Ca with a mechanised flame photometric micro-method. Mechanised micro-method ("injection method") of flame photometry (atomic absorption--atomic emission) for the determination of serum electrolytes and trace elements (Fe, Cu, Zn); Part I. (author's transl)].

By introduction of the analysis solution in measured quantities in atomic absorption and atomic emission spectrometry, the quantity sensitivity of these methods can be increased by an order of magnitude, while the concentration sensitivity remains unchanged. The required volume of sample (serum) is thereby considerably reduced. Using this method, the serum electrolytes and certain trace elements can be determined simply and quickly in only a few microlitres of serum. The automation of this micro-sample application ("injection method") largely abolishes individual errors, and markedly shortens the time for the analysis of large series of samples. The first part of this paper describes the determination of serum electrolytes and lithium, using only 5--20 microliters of serum.

Calcium

[Comparative studies of the initial rate method (modified Centrifi Chem method) and the Frankonit method to assay creatinine in serum and urine (author's transl)].

In the method described, by modification of the measurement according to changing reagent blanks (7 g albumin/100 ml + reagent for serum, and water + reagent for urine), excellent agreement with the results obtained by the Frankonit method was found. 262 parallel determinations with serum and 103 with urine were carried out. With a correlation of 0.99, the regression line y = x was almost maintained.

Creatinine

A new method for investigating the relation between change and initial value in longitudinal blood pressure data. II. Comparison with other methods.

Whether initial value affects blood pressure change or not is of interest in longitudinal blood pressure studies. The change/initial value relationship is, however, biased by the regression towards the mean phenomenon, as blood pressure measurements contain random errors (short-term intra-individual variation and measurement errors). Two methods (here called C and D) of avoiding this bias have earlier been proposed and used in population studies in South Wales and Framingham, with conflicting results. In the preceding paper a new method of avoiding the bias has been presented. In the present paper a comparison of the new method with the two earlier is made by applying them to the same data set. Method C indicates, as in South Wales, a highly significant positive relationship, while method D (as in Framingham) and the new method give a regression coefficient close to zero. The structure of the three methods is analysed. Method C is shown to be valid only under very restricted conditions and is best avoided. Method D gives a fairly accurate result, but underestimates the coefficient by approximately 30% in this case. The new method proposed seems to be the best method hitherto for this kind of analysis.

Blood Pressure Determination

[Consideration on the King-Armstrong method and on the kinetic method for the measurement of the alkaline phosphatase activity in serum (author's transl)].

The comparative study of a determined time method, according to King-Armstrong, for the measurement of the alkaline phosphatase activity in serum and of a kinetic method consents us to make the following points: 1) the reagents used in the King-Armstrong method are easily prepared and are stable for months, with the sole addition of cloroform to the substrate and to the buffer to avoid the growth of moulds. 2) The substrate used for the kinetic method undergoes spontaneous Xydrolysis in acqueous solution, which makes it possible to keep it refrigerated for a limited number of days. Freezing at - 20 degrees C does not improve the situation. 3) The degree of precision within the series and between the series is the same for the two methods, and very good. 4) From the working point of view the method of "determined time" is advantageous for few samples, while the kinetic method becomes preferable when the number of samples goes over 20 and 30 a day, provided that it is linked with the suitable automatic apparatus. 5) The results of the measurement of the enzyme activity found with the two methods on 120 sera of normal and pathological subjects have shown good correlation, confirming the clinical diagnostic value of the results obtained by the kinetic method, which uses a transphosphorilant buffer and their congruency with those obtained by the classical King-Armstrong method.

Alkaline Phosphatase

The effectiveness of the psychodramatic double method, the reflection method, and lecturing in the training of empathy.

Studied the effectiveness of the psychodramatic Double method, the Reflection method, and the Lecture method in improving empathic ability. Sixty-four high school sophomores were assigned randomly to four groups of 16 Ss, 8 males and 8 females, each. Three groups received one of the three training methods and the fourth served as no-training control. The Ss' level of empathy, before and after the training, was measured by a modified version of the Accurate Empathic Scale. The results showed that all three training methods produced significant improvements compared with the control group. The effect of the Double method was significantly greater than that of the other two methods. The Reflection method ranked second, yet was not significantly better than the Lecture method. Females scored higher than males both before and after the training, but there was no significant sex and training method interaction effect.

Adolescent

Evaluation of automated glucose oxidase methods for serum glucose: comparison to hexokinase of a colorimetric and an electrometric method.

Two automated glucose oxidase methods have been evaluated with respect to accuracy, precision, recovery, linearity and various potential interferences. Trinder's method on an AutoAnalyzer II had a between-day coefficient of variation (C.V.) of 2.6% (mean 228 mg/dl), was linear to 500 mg/dl, and produced a mean recovery of 99.7%. Comparison of Trinder's method with a manual, blanked hexokinase method yielded the regression equation: TR=--1.95 + HEX (1.04); Spearman's rho correlation coefficient was: 0.974. The Beckman System I glucose method had a between-day C.V. of 1.6% (mean 198 mg/dl), was linear to 500 mg/dl, and recovered an average of 98.0% of added glucose. Comparison with the same hexokinase method yielded: SYI = 1.27 + HEX (1.02: Spearman's rho = 0.991. None of the possible interfering compounds tested caused significant deviation of results by either method within the range of concentrations encountered physiologically. Trinder's method on the AutoAnalyzer II and the System I method are accurate, precise methods and are highly recommended for routine use in the clinical laboratory.

Autoanalysis

Comparison of titration results of diphtheric antitoxic antibodies obtained by means of Jensen's method and the methods of tissue cultures and haemagglutination.

In 33 human sera the determination of diphtheric antitoxic antibodies was performed in a double blind test using Jensen's method, the method of tissue cultures and the haemagglutination method. In the method of tissue cultures the antibody levels in the sera were determinated in the first and second experiment with the precision of +/- half dilution of the geometrical progression. In Jensen's method, the difference between the first and second measurements slightly exceeded +/- 1 dilution. In the haemagglutination method the error considerably exceeded the binary step dilution. In most cases, the determination fluctuated up to seven times the actual value. Differences among the mean values of examination results obtained by Jensen's method and the method of the tissue cultures are statistically insignificant. The differences between the haemagglutination method and both the other methods are statistically significant.

Analysis of Variance

A rebreathing method for measuring carbon monoxide diffusing capacity. A supplement to the single-breath method.

A rebreathing method for measuring carbon monoxide diffusing capacity is described. The method can be used in patients whose vital capacity is too small, or whose cooperation is inadequate, for the single-breath method. The apparatus is simple and the same gas mixtures are used as for the single-breath method. The results obtained by the rebreathing method are similar to those by the single-breath method (80% of the results by the rebreathing method lie within 20% of the value by the single-breath method). The rebreathing method also provides a measurement of the functional residual capacity.

Carbon Monoxide

Newly Developed Structure-Based Methods Do Not Outperform Standard Sequence-Based Methods for Large-Scale Phylogenomics.

Recent developments in protein structure prediction have allowed the use of this previously limited source of information at genome-wide scales. It has been proposed that the use of structural information may offer advantages over sequences in phylogenetic reconstruction, due to their slower rate of evolution and direct correlation to function. Here, we examined how recently developed methods for structure-based homology search and tree reconstruction compare with current state-of-the-art sequence-based methods in reconstructing genome-wide collections of gene phylogenies (i.e. phylomes). While structure-based methods can be useful in specific scenarios, we found that their current performance does not justify using the newly developed structure-based methods as a default choice in large-scale phylogenetic studies. On the one hand, the best performing sequence-based tree reconstruction methods still outperform structure-based methods for this task. On the other hand, structure-based homology detection methods provide larger lists of candidate homologs, as previously reported. However, this comes at the expense of missing hits identified by sequence-based methods, as well as providing sets of homolog candidates with higher fractions of false positives. These insights help to guide the use of structural data in comparative genomics and highlight the need to continue improving structure-based approaches. Our pipeline is fully reproducible and has been implemented in a Snakemake workflow. This will facilitate a continuous assessment of future improvements of structure-based tools in the AlphaFold era.

Phylogeny

Cutaneous immunohistochemistry. The direct immunoperioxidase and immunoglobulin-enzyme bridge methods compared with the immunofluorescence method in dermatology.

Two immunohistochemical methods, using the enzyme horseradish peroxidase, the direct immunoperoxidase (DIP) and the immunoglobulin-enzyme bridge (IEB) method were applied on 129 skin specimens of 81 patients with lupus erythematosus, bullous pemphigoid, pemphigus vulgaris and rosacea. These methods were compared with each other and with the immunofluorescence (IF) method. The DIP method was preferred to the IEB method because of the greater contrast between the specific staining and the nonspecific staining of the former. The results obtained with both peroxidase methods were comparable with those of the IF method.

Fluorescent Antibody Technique

[The fecal flora of man. IV. Communication: Comparison of the newly developed method with the old conventional method for the analysis of intestinal flora (author's transl)].

The results of 42 fecal flora analysis of healthy adult men were compared by using a newly developed method and an old conventional method. Statistical estimate indicate, that with the new method the total counts and the counts of bifidobacteria, catenabacteria (eubacteria and anaerobic lactobacilli), peptostreptococci, and clostridia (except Cl. perfringens) as well as the occurences of peptostreptococci and spirillaceae were significant higher than with the use of the old method. On the other hand the counts and occurences of bifidobacteria, veillonellae, Cl. perfringens, Megasphaerae and aerobes were similar with both method. With the new method the total counts of feces of healthy adult men nubmered 1-2 X 10(11) per g wet weight, and fastidious anaerobes, such as bacteroides, catenabacteria and peptostreptococci, were always occurred as predominant flora. The results suggest that the conventional anaerobic jar method is inadequate for the isolation of fastidiuos anaerobes and indicate that the use of modified medium 10 in combination with strict anaerobic technique is necessary for the analysis of fecal flora.

Adult

[Comparison of conventional methods for the determination of albumin, transferrin and ceruloplasmin in serum with immunological reference methods (author's transl)].

Radial immunodiffusion, which is a presently accepted reference method, was compared with the mechanized immunoprecipitation. Each of these specific methods was compared with two normal clinical-chemical methods for the determination of albumin and transferrin, and an enzymic method for the determination of ceruloplasmin. The correlation coefficients, the mean slope for regression, and the percentage variation of the average values from those of the average values of the reference methods are presented. In the determination of albumin and ceruloplasmin, radial immunodiffusion and mechanized immunoprecipitation give the same results. Surprisingly, these two specific methods give different results in the determination of transferrin. In as far as there is no doubt concerning the accuracy of the mechanized immunoprecipitation, this method is recommended, since it also has the advantage of being less demanding in cost and time.

Autoanalysis

An enhanced multisegment RT-PCR method for influenza A virus sequencing: Improved performance and reduced preparation time over traditional methods.

Influenza A viruses (IAVs) remain a major global health threat, affecting both human and animal populations. Whole-genome sequencing is essential for monitoring viral evolution, zoonotic transmission, and emerging variants. However, conventional RT-PCR methods often result in incomplete gene coverage, amplification biases, and reduced sequencing accuracy, particularly in clinical samples. We developed a robust In-house method for IAV full-genome sequencing using the Oxford Nanopore Technologies (ONT) long-read sequencing platform. This method integrates an in-house multisegment Reverse Transcription PCR (RT-PCR) method with a streamlined 2-pool primer design targeting all eight IAV gene segments. RNA extracted from clinical and stock virus samples was reverse-transcribed and amplified using Superscript IV-based chemistry, followed by magnetic bead purification to ensure high-quality amplicons. Sequencing libraries were prepared with the Native Barcoding Kit 24 (SQK-NBD114.24) and sequenced on R10.4.1 flow cells on the MinION MK1C device. Data analysis using the Iterative Refinement Meta-Assembler (IRMA) confirmed improved read depth, uniform coverage, and complete genome recovery. Compared to conventional methods, our In-House Multisegment 2-Pool (IH-MS2P) RT-PCR method generated higher numbers of matched read counts, minimized chimeric artifacts, and delivered superior genome coverage across human, swine, and avian isolates. This optimized RT-PCR method provides a high-performance, time-efficient, and portable solution for influenza genomics, demonstrating robust applicability even with clinical samples of low RNA yield.

Influenza A virus