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At least 1,531 records · Page 85Linked to original sources
PubMed1991

Successful careers and cognitive style: a follow-up study of childhood family discontinuity.

It was predicted that those participants who experienced discontinuity (death, divorce, and separations) from their parent(s) in childhood and who had successful careers in adulthood would manifest more innovative than adaptive cognitive styles on the Kirton Adaption-Innovation Inventory. The original research showed 61% of the sample members (n = 41) experienced family discontinuity. Ninety percent (n = 37) of the previous participants responded and showed 59% family discontinuity. Fifty-four percent in the follow-up study chose an alternative career path (counterstriving), the same percentage as in the original sample. When both family discontinuity and counterstriving were present, statistically significant innovation scores occurred. Family discontinuity in childhood and a successful career in adulthood are likely to be associated with high striving-motivation and an innovative (paradigm-breaking) problem-solving style.

Adaptation, Psychological↗
PubMed2006

Adaptive two-stage designs in phase II clinical trials.

Two-stage designs have been widely used in phase II clinical trials. Such designs are desirable because they allow a decision to be made on whether a treatment is effective or not after the accumulation of the data at the end of each stage. Optimal fixed two-stage designs, where the sample size at each stage is fixed in advance, were proposed by Simon when the primary outcome is a binary response. This paper proposes an adaptive two-stage design which allows the sample size at the second stage to depend on the results at the first stage. Using a Bayesian decision-theoretic construct, we derive optimal adaptive two-stage designs; the optimality criterion being minimum expected sample size under the null hypothesis. Comparisons are made between Simon's two-stage fixed design and the new design with respect to this optimality criterion.

Clinical Trials, Phase II as Topic↗
PubMed2002

Molecular classification of primary breast tumors possessing distinct prognostic properties.

The natural progression of breast cancer differs greatly between patients; the precise prediction of this disease course will improve the efficacy of therapeutics. Gene expression profiling may elucidate the undiscovered biological variations between seemingly similar cancers, leading to a new cancer classification system valuable in accurate diagnosis. The expression levels of 2412 genes, derived from 98 cancer samples, were precisely recorded by a high throughput RT-PCR technique, adapter-tagged competitive PCR. Subsequent cluster analysis revealed a molecular profile, correlating with estrogen receptor levels and the presence of lymph node metastases. We analyzed 301 cancer samples for the expression patterns of 21 genes critical in this categorization. The classification of the samples into three major groups was verified utilizing principal component analysis. This molecular classification system correlated significantly with early recurrence, independent of lymph node status. This malignant potential is associated with the expression levels of a group of genes, which comprise a set of candidates potentially useful in diagnostic prediction. These genes and the associated control mechanisms may also be effective therapeutic targets.

Breast Neoplasms↗
PubMed1988

A factor analysis of the Kirton Adaption-Innovation Inventory using an alcoholic population.

The present study reports a factor analysis of the Kirton Adaption-Innovation Inventory using 103 alcoholic men. Kirton in 1976 and we in an unpublished work in 1986 noted identical factor structures when responses from nonalcoholic populations to the inventory were factor analyzed. Recent reviews regarding personality characteristics of alcoholics suggest characteristics similar to the adaption-innovation concepts of Kirton. This factor analysis for an alcoholic sample supports the validity of the inventory as a measure of problem-solving style of alcoholics.

Adaptation, Psychological↗
PubMed1992

[Sodium and potassium metabolism in infancy].

BACKGROUND: Recommendations for the concentration of most nutrients in infant formulas are based on their concentration in human milk. Industry succeeded in adapting sodium and potassium content in infant formulas to concentration found in human milk. Whether this adaptation affects on infants' mineral balances was studied in breast-fed and artificially-fed infants. METHODS: Sodium and potassium balances were performed in 16 term male infants from their 3rd until their 17th week of life. The balances were performed at home and comprised up to five periods in intervals of three to four weeks. Each balance period consisted of subsequent three 24 h collections of milk, stool and urine samples. Ten infants were breast-fed, six received an adapted infant formula supplemented with copper, zinc and iron. RESULTS: The breast-fed infants got a mean intake of 1 mmol Na/kg b w x day and a mean intake of 1.8 mmol K/kg b w x day. Man retention was 0.4 mmol Na and 0.7 mmol K/kg b w x day. The formula-fed infants received 1.9 mmol Na/kg b w x day and 2.1 mmol K/kg b w x day. Na- and K-retention in this group was 0.5 and 0.6 mmol/kg b w x day respectively. Although sodium intake in the formula-fed infants was nearly twice as much as in the breast-fed infants the difference in sodium retention was only small (0.4 vs 0.5 mmol/kg b w x day). The formula-fed infants got more potassium than the breast-fed infants, but potassium retention was the same in both groups. CONCLUSIONS: With the adapted infant formula of this study the artificially fed infant was as well supplied with sodium and potassium as the breast-fed infant. A further reduction of the sodium concentration seems not to be useful.

Animals↗
PubMedDate not supplied

Biosensors in flow-injection systems for biomedical analysis, process and environmental monitoring.

This paper presents the construction of various biosensors using thin-film layers incorporated in flow injection devices, providing automated systems for biomedical analysis, process and environmental monitoring. A urease sensor has been developed in conjunction with a flow injection system for the automatic determination of urea. Use of the spraying immobilization technique gives rise to a response time of a few seconds, which allows sample throughputs up to 200 h-1. With a penicillin biosensor adapted in an appropriate cell detection, on-line measurements of penicillin V in the fermentation broth are achieved during the whole fermentation process; the results are compared with the HPLC method. Linearity, sensitivity and reproducibility of the biosensor are studied with regards to sample dilution in a stirred flow detection cell to provide optimal operating conditions. Measurements without any change in parameters are obtained during the whole fermentation process. Acetylcholinesterase sensors have been used in batch systems for the determination of pesticides, but they require large amounts of substrate. When those enzyme sensors are combined with flow injection systems, only small volumes (100 microliters) of substrate are injected into the carrier stream and an automated system can be obtained for continuous control of water quality.

Biosensing Techniques↗
PubMed1986

Detection of trace levels of trichothecenes in human blood using capillary gas chromatography-electron-capture negative ion chemical ionisation mass spectrometry.

A sensitive and selective method has been developed for the simultaneous detection in blood of eleven trichothecenes of widely varying polarity. The procedure involved precipitation of blood proteins with acetone followed by a clean-up using reversed-phase Sep-Pak C18 cartridges. The extracted trichothecenes were derivatised as their pentafluoropropionyl esters, separated using capillary gas chromatography and detected using electron-capture negative ion chemical ionisation with methane reagent gas and selected-ion monitoring. Optimum sensitivity and selectivity were obtained using low source temperatures (60 degrees C indicated) and high source pressures (1 Torr indicated). Detection limits on 1-ml blood samples were in the range 0.1-5 ppb. The method was readily adaptable to the detection of other trichothecenes. A protocol was used which minimised the risk of cross-contamination. The method was validated in collaborative studies by the successful analysis of 42 blood samples spiked and submitted blind by two independent laboratories for analysis.

Chemical Phenomena↗
PubMed1994

Irrational beliefs and depressive symptoms among younger and older adults: a cross-sectional comparison.

The present study explored age differences in the expression of depression. Such differences were quite apparent. Among 118 young adults and 107 community-residing elderly individuals, it was found that in the young adult groups, cognitive belief factors labeled "externality/control" and "dependency/emotionality" were associated with both affective and cognitive aspects of depression, but not somatic depressive symptoms over and above the influence of sociodemographic factors. In contrast, among older adults, a cognitive belief factor labeled "cognitive-emotional rigidity/dependency" was uniquely associated with both affective and somatic depressive symptoms. Additionally, a second cognitive factor, labeled "adaptation/internal control" defined in terms of the absence of irrational thinking about adaptation and control, was negatively related to somatic depressive symptoms. For each sample, poorer health was associated with greater depressive symptomatology. While these findings generally tend to support a cognitive view of depression in adulthood, they also underscore the importance of cognitions that may be adaptive which mitigate distress among older persons.

Adaptation, Psychological↗
PubMed1976

Morphological adaptation to thermal stress in a marine fish, Fundulus heteroclitus.

Populations of Fundulus heteroclitus (Cyprinodontidae), a coastal marine fish, were studied in control and artificially heated environments on the north shore of Long Island to determine patterns of variation in morphology and the extent to which this variation reflected adaptation to environmental characteristics. Principal components and discriminant function analyses were used to analyze variation in and among seventeen morphological characters. Fishes living in water artificially heated by a power plant exhibited marked divergence from control populations in head morphology, and convergence with a population sampled at more southern latitudes. Hence, these differences were interpreted as adaptations to warm environments. Greater morphological variation is detected at the heated locality than at control localities, and this may be partially due to a breakdown in developmental homeostasis, and partially due to selection favoring phenotypes that are rare in this environment.

Adaptation, Physiological↗
PubMed2005

An adaptive method for cDNA microarray normalization.

BACKGROUND: Normalization is a critical step in analysis of gene expression profiles. For dual-labeled arrays, global normalization assumes that the majority of the genes on the array are non-differentially expressed between the two channels and that the number of over-expressed genes approximately equals the number of under-expressed genes. These assumptions can be inappropriate for custom arrays or arrays in which the reference RNA is very different from the experimental samples. RESULTS: We propose a mixture model based normalization method that adaptively identifies non-differentially expressed genes and thereby substantially improves normalization for dual-labeled arrays in settings where the assumptions of global normalization are problematic. The new method is evaluated using both simulated and real data. CONCLUSIONS: The new normalization method is effective for general microarray platforms when samples with very different expression profile are co-hybridized and for custom arrays where the majority of genes are likely to be differentially expressed.

Calibration↗
PubMed1996

Reproducibility of simplified techniques for the measurement of 51Cr-EDTA clearance.

The aim of this study was to assess the reproducibility of a number of simplified clearance methods using chromium-51 ethylenediamine tetraacetic acid (51Cr-EDTA) and to compare these with the multiple blood sample technique. Twenty-four healthy volunteers were enrolled into the study. The test was performed twice, 1 week apart and under similar physiological conditions. After intravenous injection of the tracer, 13 blood samples were taken between 5 and 240 min. The reference clearance was calculated after adapting a bi-exponential fit on the whole plasma disappearance curve. Simplified methods included the slope intercept method using different combinations of blood samples (2 and 4 h; 2, 3 and 4 h; 1.5, 2, 3 and 4 h; 1.5, 2 and 3 h) and several single clearance methods (Constable 3 h; Groth 3 h; Groth 4 h). The standard deviation of the differences between the first and second measurements were similar for all methods, confirming the comparable reproducibility of these methods.

Chromium Radioisotopes↗
PubMed1995

A survey of U.S. Air Force flight nurses' adaptation to service in Vietnam.

This descriptive study reports the experiences of a voluntary sample of 20 Air Force nurses in the San Antonio, TX area, who served in the Vietnam theater of operations at various times during the Vietnam War. Of the sample, 65% were assigned to flying squadrons, 15% to aeromedical evacuation staging units, and 20% to combat support hospitals. Indepth interviews concentrated on individual perceptions of wartime experiences, coping skills used, and significant events remembered. Thematic content analysis was used to describe, summarize, and classify data. Each nurse responded to this professional challenge in a unique way. Reactions to a combat environment and resolution of experiences from the Vietnam War confirmed Horowitz's Stress Response Theory. Findings confirmed the notion of intensity and Post-Traumatic Stress Disorder (PTSD). Of those in this sample who served during the Tet Offensive 25% reported symptoms of PTSD. Respondents reported strong social support, maturity, nursing experience, humor, religion, and relaxation as crucial survival skills. Of the nurses interviewed, 60% cited patient care situations and threats to survival as the most significant events remembered. Serving in the Vietnam War proved their most rewarding professional experience.

Adaptation, Psychological↗
PubMed1986

Adaptation of pregnant rhesus monkeys to short-term chair restraint.

Heart rate, blood pressure, temperature and plasma corticosteroids were measured in pregnant rhesus monkeys during 23 successive 2 hour chair restraint periods beginning in midgestation. Heart rate (15%), blood pressure (13%) and plasma cortisol (23%) declined from first to last sessions. Reduction in physiological indicators of stress was most marked during the first three sessions, but continued in some animals over the 8 week period. Pulse rate and blood pressure were elevated at the beginning of each session and dropped to base-line levels during the second hour. In contrast, plasma cortisol consistently rose during the 2 hour session. Blood sampling and palpation were conducted at weekly intervals during the adaptation series. Immediate physiological responses to these manipulations did not diminish with repetition, although behavioral adaptation was observed. The data suggests that objective measurements of adaptation to chair restraint are important in determining the appropriateness of this procedure. Chair restraint is a valuable alternative to chemical or manual restraint in obtaining sequential evaluations in pregnant monkeys.

Adaptation, Physiological↗
PubMed2001

Detection of hepatitis A virus by the nucleic acid sequence-based amplification technique and comparison with reverse transcription-PCR.

A nucleic acid sequence-based amplification (NASBA) technique for the detection of hepatitis A virus (HAV) in foods was developed and compared to the traditional reverse transcription (RT)-PCR technique. Oligonucleotide primers targeting the VP1 and VP2 genes encoding the major HAV capsid proteins were used for the amplification of viral RNA in an isothermal process resulting in the accumulation of RNA amplicons. Amplicons were detected by hybridization with a digoxigenin-labeled oligonucleotide probe in a dot blot assay format. Using the NASBA, as little as 0.4 ng of target RNA/ml was detected per comparison to 4 ng/ml for RT-PCR. When crude HAV viral lysate was used, a detection limit of 2 PFU (4 x 10(2) PFU/ml) was obtained with NASBA, compared to 50 PFU (1 x 10(4) PFU/ml) obtained with RT-PCR. No interference was encountered in the amplification of HAV RNA in the presence of excess nontarget RNA or DNA. The NASBA system successfully detected HAV recovered from experimentally inoculated samples of waste water, lettuce, and blueberries. Compared to RT-PCR and other amplification techniques, the NASBA system offers several advantages in terms of sensitivity, rapidity, and simplicity. This technique should be readily adaptable for detection of other RNA viruses in both foods and clinical samples.

Blueberry Plants↗
PubMed2001

Measuring adaptive behavior in inpatient neuropsychiatry: the Behavioural Assessment Scale.

The Behavioural Assessment Scale (BAS) was administered to a sample of 95 inpatients with neuropsychiatric conditions. The total scores in the sample ranged from 26 to 145 (maximum possible score is 163), without any evidence of the "floor effect" encountered with other tests used with this population. Investigation into the psychometric structure of the BAS revealed three factors interpreted as Daily Living Skills, Communication/Social Skills, and Problem Behavior. The high intercorrelation between the two dominant factors was interpreted as general sensitivity of the BAS to global decline in functioning associated with severity of illness. These results confirm a previous psychometric investigation carried out on an elderly psychiatric sample. A recommendation is made for interpreting subscales based on these factor domains when specific abilities are of interest and using a Global Functioning subscale as a measure of overall adaptive behavior for both adult and geriatric inpatient neuropsychiatry patients.

Activities of Daily Living↗
PubMed1990

Limits of detection of bluetongue virus with different assay systems.

The sensitivity of different assay systems for detecting low concentrations of bluetongue virus (BTV) were compared. These assays included blind passage on baby hamster kidney (BHK-21) cells and on cattle pulmonary artery endothelial (CPAE) cells, immunoperoxidase staining of cells on multiwell slides, and cDNA/RNA hybridization of BTV infected cells. Nine serial 10-fold dilutions of a cell culture-adapted BTV serotype 11 were tested (each dilution was treated as a separate sample) in all assays. Visual inspection for cytopathic effects (CPE) during 3 passages in BHK-21 cells detected samples that contained greater than or equal to 3 plaque forming units (PFU)/ml of BTV. Evidence of CPE during 3 passages in CPAE cells detected samples that contained greater than or equal to 0.3 PFU/ml of BTV. A limit of detection (greater than or equal to 0.3 PFU/ml) was obtained faster by immunoperoxidase staining of BTV-inoculated CPAE cells on multiwell slides and incubated for 3 days. The cDNA/RNA hybridizations of CPAE and BHK-21 cells incubated for 2 or 3 days, respectively, with BTV dilution samples detected samples that contained greater than or equal to 30 PFU/ml. Of the assay systems examined, immunoperoxidase staining of CPAE cells on multiwell slides inoculated with cell culture-adapted BTV was the most sensitive and fastest assay for definitive virus identification.

Animals↗
PubMed2001

Measurements of urinary leptin and capillary leptin: alternative tools for the assessment of the leptin status?

OBJECTIVES: The aim of this study was to check whether leptin is reliably measurable in urine samples of children, adolescents, and adults and to examine whether capillary leptin measurements can be utilized as an alternative tool to assess the leptin status. METHODS: Two studies were performed. In both studies, leptin was quantified by an ultrasensitive and highly specific enzyme immunoassay (ELISA; R & D Systems). Anthropometric measures were taken from all study subjects, and body fat was calculated using skinfold thickness measurements. In study 1, leptin was analyzed in 24-hour urine samples of 155 healthy children and adolescents and 26 healthy adults after a methodological modification of the assay necessary for urine analysis. In study 2, venous and capillary blood samples were collected in 26 healthy adults within 10 min on the same day. RESULTS: After adapting the assay system to urine matrix, the detection range was 20-160 pg/ml. Only in 2 of 181 urine samples reproducibly measurable urinary leptin concentrations in the lowest detection range were found. In study 2, a close correlation was found between log capillary and log venous leptin concentrations (r = 0.98, p < 0.001) and between log capillary as well as log venous leptin levels and percent body fat (r = 0.86, p < 0.001). CONCLUSIONS: Our results based on one of the most specific and sensitive ELISAs currently available show that leptin is generally undetectable in the urine from healthy children, adolescents and adults. Thus, urinary leptin excretion cannot be used as a noninvasive marker of the leptin status. Our findings in healthy adults show that the merely moderately invasive determination of capillary leptin allows a reliable assessment of the individual leptin status and may be used instead of venous leptin as a biochemical indicator of body fatness.

Adolescent↗
PubMedDate not supplied

The Häma-COM laboratory data management system (LDS): tailor-made computerization of the individual working procedures arising in a hematology laboratory with a high throughput of pathologic samples.

A laboratory data management system (Häma-COM) is presented that is individually adaptable to the different working procedures arising in a hematology laboratory. The Häma-COM can be easily integrated into a hospital and/or another laboratory computer system, providing the facilities of total electronic data transfer between the referring institutions and the laboratory. The system is based on a network of personal computers running Novell Network software and coordinates two hematology analyzers (NE-8000, R-1000) and several microscopic work stations. The entire information provided by the hematology analyzers including scatterplots and histograms is captured by the system, whereby automated results are validated and worklists for further sample workup are created. Corrections of and/or additions to automated analysis results might be directly entered into the system from the respective microscopic working places. The Häma-COM system minimizes the administrative workload without interfering with the individual laboratory organization.

Blood Cell Count↗