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At least 19 recordsLinked to original sources
PubMed1989

[Human gingival fibroblast cultures for biological intra-oral material testing].

Cell cultures are useful screening methods for biocompatibility tests, as they provide information on the effects of test material on their metabolism. Primary cultures of human gingival fibroblasts play a special role, because they are organ-specific and because their metabolic state is virtually the same as that of in vivo cell material. Their characteristic growth pattern makes them excellent candidates for testing toxicity and stimulatory factors. Four methods were used for validating the data obtained. Possibilities of culturing these highly specialized cells are shown, techniques for assessing the cytotoxicity of test materials are presented and discussed.

Autoradiography↗
PubMed1984

Toxicity testing of medical device materials tested in human tissue cultures.

Rubber and plastic parts of medical devices were applied to human cell monolayers either directly or as aqueous extracts made at different time/temperature conditions. Thirteen rubber and twelve plastic samples were tested. The cultures were observed and photographed by use of a microscope with a camera before and after treatment with the test materials. The toxicity of the specimens was evaluated by comparison of the photographs. Alterations or disappearance of the cells or inhibited growth were interpreted as toxic effects of the materials. Twelve of the rubber and six of the plastic samples were evaluated as toxic in one or more of the systems.

Culture Techniques↗
PubMed1976

[Proposal for the introduction of microbial test material in compost windrows for field test (author's transl)].

The introduction and taking of microbial test material for field tests in compost windrows for e.g. the determination of the death rates of patogenic microbes cause various problems in practical use whereby the results of such investigations may be influenced. A device is suggested which allows unlimited microbes taking with the greatest reservation of the windrows and guarantees that during the experiment the introduced microbial test material is actually exposed to the same influences as its neighbouring windrow parts. Comparisons with other methods used are being made.

Bacteria↗
PubMed1997

The effects of modifying proficiency testing materials on thyroid function test results. A College of American Pathologists Ligand Assay Survey Study.

OBJECTIVE: To gain insight on the matrix effects, and possible clinical implications, resulting from diluting and concentrating proficiency testing survey material used for the measurement of thyroid function tests. DESIGN: To the standard set of five proficiency survey samples, three supplementary "Wildcard" samples were added. These additional samples were manufactured by overfilling and underfilling vials prior to lyophilization so as to vary the thyroxine-binding protein concentrations. Survey participants measured thyroxine, free thyroxine, and the triiodothyronine uptake and related tests on the Wildcard samples. In addition, free thyroxine indices were calculated. SETTING: The first mailing of the 1995 College of American Pathologists (CAP) Ligand Assay--Series 1 Survey. MAIN OUTCOME MEASURES: Results obtained from the regular set of survey samples and the Wildcard set were compared to values expected by the laws of conservation of matter and mass action. PARTICIPANTS: The approximately 2000 participants of the first mailing of the 1995 CAP Ligand Assay--Series 1 Survey. RESULTS: Numerous assays systems did not give the predicted results, including all of the single-step radioimmunoassays for free thyroxine and over three quarters of free thyroxine index determinations. CONCLUSIONS: Varying the dilution of proficiency survey material produced results that were not predicted by the laws of conservation of matter and of mass action. Although these observations may have been the result of matrix effects, one cannot rule out the possibility that certain thyroid assays may not work in clinical situations having abnormal thyroxine-binding protein concentrations.

Data Collection↗
PubMed2006

[Development and equivalence evaluation of monosyllable lists of mandarin speech test materials].

OBJECTIVE: To find a good speech material in audiology routine tests and cochlear implant evaluation, the monosyllable lists which were a part of mandarin speech test materials (MSTM) were edited and recorded. The equivalence test was done for all the lists. METHODS: The professional group was set up at first, which composed of specialists of Chinese, mandarin teaching, linguistics and statistics. The principles of word selection were established according to the coherence with international speech test materials and mandarin. Ten Monosyllable lists, each of which has 50 mandarin words according to phonemic balance and criteria of speech audiometry, were edited. The balance was 3-dimension: vowels, consonants and four Chinese tones. One cassette was recorded by a male speaker (radiobroadcaster). The 72 normal hearing subjects were tested monaurally with ten monosyllable lists and the materials were presented by the earphone. The equivalence evaluation was done at the level of about 50% correct scores. RESULTS: Statistic analysis shows that 7 lists were equivalent in difficulty. They were ready for future research and clinical trial. CONCLUSIONS: The mandarin monosyllable lists were edited in terms of international standard and Chinese 3-dimension phonemic balance. Seven of them met the demands for research and clinical application.

Adult↗
PubMed1985

Cautions in alternate-form presentation of aural test material: Speech Sounds Perception Test.

86 college students were administered the standard Speech Sounds Perception Test and an alternate recording. Although reliability between the two recordings was moderate (r = .68) when the standard was given first, but only .36 when the alternate form was given first, differences in performance were consistent with differences in attack and decay found in voice-print tracings. Results suggest caution in using an alternate form of a neuro-psychological test, particularly one using auditory stimuli, until cross-validation confirms the reliability coefficient and the level of performance.

Adult↗
PubMed2005

Comparison of fresh frozen serum to traditional proficiency testing material in a College of American Pathologists survey for ferritin, folate, and vitamin B12.

CONTEXT: Comparison of different analytical methods in proficiency surveys may be affected by the artificial nature of the survey material. OBJECTIVE: To compare intermethod differences in proficiency survey results between 2 types of survey material, conventional proficiency testing material (PTM) and fresh frozen human serum (FFS), for 3 markers of anemia: ferritin, folate, and vitamin B12. DESIGN: Data were gathered from a 2003 survey event in the College of American Pathologists Ligand ("K") Series, in which the specimens to be tested by each participating laboratory included 1 vial of FFS and 2 vials of PTM with different analyte concentrations. The more than 1600 laboratories subscribing to the survey were not advised as to the nature of the specimens. MAIN OUTCOME MEASURES: The bias of each method relative to the median of method means for each analyte and each type of survey material, and the interlaboratory coefficient of variation for each method. RESULTS: For each of the 3 analytes, moderate to large method biases were observed. For ferritin, method biases correlated strongly between comparable PTM and FFS specimens (Spearman r = 0.863, P < .001), whereas virtually no correlation was found for folate (r = -0.224, P = .48), and a marginally significant correlation existed for B12 (r = 0.55, P = .049). CONCLUSIONS: With ferritin, proficiency survey performance of PTM is similar to that of FFS, implying that method biases relate mainly to calibration. With folate and to a lesser extent with B12, PTM and FFS exhibit different method biases, implying that the biases reflect analyte heterogeneity and/or matrix effects.

Clinical Laboratory Techniques↗
PubMed1983

Inspection of the Bayley Mental Scale test materials for potential hazards of choking, aspiration, and ingestion when used outside of test situation.

The test materials of the Bayley Scales of Infant Development were inspected for potential choking, aspiration, and ingestion hazards by unsupervised children under 36 mo. of age. When the small-parts test cylinder, defined by the Federal Code of Regulations, was used for the inspection, four pieces of test materials were judged too small: the doll with detached head, sugar pellets, the rabbit, and yellow cubes.

Airway Obstruction↗
PubMed1998

Nickel content of standard patch test materials.

The nickel sulfate content in standard patch test materials currently used in the US, Europe and Japan was determined by inductively-coupled plasma atomic emission spectroscopy, a state-of-the-art microanalytical method which allows nickel detection to levels of 7 ppb (microg/l). In 2 materials with a nominal concentration of 5% nickel sulfate hexahydrate in pet., the range (calculated averages of triplicate analyses of 3 different batches) was from 4.72 to 4.87% and 4.97 to 5.39%, respectively. In 1 material with a 2.5% nominal concentration in pet., the values ranged from 2.41 to 2.48%. The range seen in a 5% NiSO4 hexahydrate aq. material was 4.95 to 5.03%. The range for 2.5% NiSO4 anh. in pet. was 2.39 to 2.49%. This data suggest a significant improvement in quality control compared to our previously published data.

Allergens↗
PubMed2006

[Development and equivalence evaluation of spondee lists of mandarin speech test materials].

OBJECTIVE: To edit the spondee (disyllable) word lists as a part of mandarin speech test materials (MSTM). These will be basic speech materials for routine tests in clinics and laboratories. METHODS: Two groups of professionals (audiologists, Chinese and Mandarin scientists, linguistician and statistician) were set up at first. The editing principles were established after 3 round table meetings. Ten spondee lists, each with 50 words, were edited and recorded into cassettes. All lists were phonemically balanced (3-dimensions: vowels, consonants and Chinese tones). Seventy-three normal hearing college students were tested. The speech was presented by earphone monaurally. Three statistic methods were used for equivalent analysis. RESULTS: Related analysis showed that all lists were much related, except List 5. Cluster analysis showed that all ten lists could be classified as two groups. But Kappa test showed that the lists' homogeneity were not well. CONCLUSIONS: Spondee lists are one of the most routine speech test materials. Their editing, recording and equivalent evaluation are affected by many factors. This also needs multi-discipline cooperation. All lists edited in present study need future modification in recording and testing in order to be used clinically and in research. The phonemic balance should be kept.

Adult↗
PubMed1979

"Reactions" to standard patch test materials.

Twelve compounds tested by closed patch test at recommended concentrations produced numerous "Fallse positive" non-allergenic reactions in a panel of 100 vollunteers. These results indicate the need for further basic studies to determine appropriate non-irritating concentrations of materials used in biagnostic patch testing for contact allergy.

Adult↗
PubMed2006

[Phoneme discrimination test material for preschool children: development and preliminary assessment].

BACKGROUND: Several tests have been developed to probe phoneme discrimination. However, little is known about the reliability and validity of discrimination abilities in preschool children as assessed by these tests. Based on previous results we now developed a test material based on minimal pair presentation. METHODS: Prospective study; 30 preschool children (5;1 to 6;3 years old, 17 boys, 13 girls); descriptive statistics and correlational analysis; items: 60 minimal pairs consisting of real words and nonsense words. RESULTS: Empirical testing confirmed prediction of normal distributed phoneme discrimination errors. No gender specific effects were found. Results correlated with the degree of phoneme opposition and with phonological loop capacity. DISCUSSION: These results indicate that the test material developed is suitable for testing phoneme discrimination in preschool children. However other normative assessments using larger test populations are warranted. Phoneme discrimination tasks appear to include testing of sensory as well as linguistic-cognitive functioning.

Age Factors↗
PubMed1994

The American Society for Testing Materials F-30 Committee on EMS.

The American Society for Testing Materials (ASTM) F-30 Committee on Emergency Medical Services (EMS) began creating voluntary consensus standards for EMS including air medical transport in 1984. The F-30 Committee is composed of more than 200 members who represent both the "producers" and the "users" of EMS. Approximately 10 of the 39 standards published by the F-30 Committee either deal directly or indirectly with air medical programs. The standards are refined through yearly evaluation and reviewed in detail every four years. Due to concerns with the ASTM process, several of the initial members resigned in 1988. Changes made to the scope and practice of the F-30 Committee have resulted in some of these participants returning to the process. New standards must be developed only after a "needs assessment" demonstrates that such a standard should exist. Relevant pre-existing standards must be reviewed. Clinical practice has been excluded from the work of the F-30 Committee. Air medical programs may participate as members of the F-30 Committee for a nominal yearly fee, which provides members with an updated book of standards. Meetings are held biannually. The Guide for Establishing the Qualifications, Education and Training of EMS Aeromedical Patient Care Providers is approaching its four-year review, and a number of other standards, which are of particular interest to the air medical community, are currently under development.

Air Ambulances↗