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At least 595 records · Page 33Linked to original sources
PubMed1999

The association between the perception of threat in a dating situation and sexual victimization.

The purpose of the present investigation was to assess the relation between threat perception in a dating situation and sexual victimization. During an initial session, participants in the experimental condition (n = 116) viewed a video that depicts a heterosexual couple interacting on a date and reflects risk factors for sexual assault. Participants in the control condition (n = 108) viewed a video that does not contain such risk factors. Participants in each condition also responded to survey instruments assessing demographic variables, history of child sexual abuse, history of adolescent sexual assault, and perception of threat cues in the stimulus videos. A subset of participants (n = 66) returned for a 5-month follow-up session and was assessed for experience of sexual assault during the follow-up period. Results fail to support an association between threat perception and sexual victimization history or an association between threat perception and sexual victimization during the follow-up period.

Adolescent↗
PubMedDate not supplied

Clinical outcome of chronic hepatitis C in patients treated with interferon: comparison between responders and non-responders.

AIM: To evaluate the prognosis of chronic hepatitis C in relation to interferon therapy response and the persistence of therapeutic benefits. PATIENTS/METHODS: We studied the clinical outcome of 191 patients with chronic infection (152 chronic hepatitis C and 39 cirrhosis) treated with recombinant alpha-interferon (3-6 MU on alternate days for 1 year) during a mean period of 47 months (range 22.5-73.8). Control tests were done at 6-month intervals. HCV RNA was determined pre- and post-treatment in all participants, but continued yearly in long-term responders. The appearance of cirrhosis was estimated using a non-invasive method that utilizes a model based on clinical, instrumental and biochemical variables. Ascites, encephalopathy, haemorrhage, hepatocellular carcinoma, and death were considered liver-disease-related events. RESULTS: A total of 39 patients were long-term responders, 36 relapsers, and 116 non-responders; 92% of long-term responders cleared HCV RNA and remained negative throughout the study period. The 3 HCV-RNA-positive long-term responders continued being so. No biochemical relapse was observed in long-term responders regardless of virological status. New cirrhosis was observed in 3/30 relapsers, in 9/85 non-responders, and in no long-term responders. Overall, 9 episodes of severe events occurred in 20% of cirrhotics and in 0.6% of chronic hepatitis, all non-responders. CONCLUSIONS: Long-term response interrupts the progression to cirrhosis and reduces the incidence of severe complications. Multivariate analysis revealed that "baseline diagnosis of cirrhosis" was the only independent factor predictive of an unfavourable outcome of chronic HCV-related liver disease.

Adult↗
PubMed1998

[Auditory P300 in assessing cognitive dysfunctions of Alzheimer's disease and schizophrenia].

OBJECTIVE: To investigate the value of auditory P300 in assessing cognitive dysfunctions of aged patients with Alzheimer's disease(AD) or schizophrenia. METHODS: An'oddball' paradigm was used to elicit the auditory P300 from 39 patients diagnosed as having Alzheimer's disease according to DSM-III-R, 34 aged schizophrenics and 40 normally age-matched subjects, by using a Dantec Concerto SEEG-16 instrument. RESULTS: The variability of P300 waveform increased in AD patients, who presented reduced N1 latency elicited by frequent stimuli. The P3 amplitude of the AD patients was lowered by 14% compared with that of schizophrenics, and by 60% than compared with that of normal controls. Compared with the normal controls, schizophrenics presented reduced N1, P2, N2 and P3 latencies, and their P3 amplitude was decreased by 54%. CONCLUSION: The auditory P300 is of value in assessing the cognitive dysfunctions of AD patients and aged schizophrenics.

Aged↗
PubMed2001

Normative behavioral thresholds for short tone-bursts.

Although tone-bursts have been commonly used in auditory brainstem response (ABR) evaluations for many years, national standards describing normal calibration values have not been established. This study was designed to gather normative threshold data to establish a physical reference for tone-burst stimuli that can be reproduced across clinics and laboratories. More specifically, we obtained norms for 3-msec tone-bursts presented at two repetition rates (9.3/sec and 39/sec), two gating functions (Trapezoid and Blackman), and four frequencies (500, 1000, 2000, and 4000 Hz). Our results are specified using three physical references: dB peak sound pressure level, dB peak-to-peak equivalent sound pressure level, and dB SPL (fast meter response, rate = 50 stimuli/sec). These data are offered for consideration when calibrating ABR equipment. The 39/sec stimulus rate yielded tone-burst thresholds that were approximately 3 dB lower than the 9.3/sec rate. The improvement in threshold with increasing stimulus rate may reflect the ability of the auditory system to integrate energy that occurs within a time interval of 200 to 500 msec (temporal integration). The Trapezoid gating function yielded thresholds that averaged 1.4 dB lower than the Blackman function. Although these differences are small and of little clinical importance, the cumulative effects of several instrument and/or procedural variables may yield clinically important differences.

Acoustic Stimulation↗
PubMed1978

Drug-induced changes in DNA fluorescence intensity detected by flow microfluorometry and their implications for analysis of DNA content distributions.

Chicken erythrocytes, which contain less DNA than mammalian diploid cells, were used as an internal standard to control instrumental and staining variables during flow microfluorometric analysis. With the DNA stain, mithramycin, and with an EPICS II flow microfluorometer, ratios between the modal G1 fluorescence of experimental cells and that of chicken erythrocytes were determined. The results indicate that unperturbed cell populations of L1210 and HeLa cells in vitro and L1210 ascites cells in vivo have relatively stable fluorescence ratios, although there is a significant difference between the ratios of one L1210 cell line in vitro and another in vivo. In contrast, L1210 ascites treated in vivo with different schedules of cyclophosphamide and Adriamycin showed wide fluctuations in the fluorescence intensity ratios for 96 hr after treatment. Also, differences in the fluorescence ratios were observed between less advanced and more advanced L1210 ascites after treatment with the same schedule. These effects indicate an alteration in DNA staining with mithramycin, brought about by drug treatment that could seriously affect the interpretation of DNA histogram data. Nevertheless, changes in mithramycin staining may prove to be a very important probe to detect persistent drug effects.

Animals↗
PubMed1992

Psychological assessment of blood related renal donors.

The impact of kidney donation on the psychological health of 31 living related donors was assessed by administering certain psychological tests before and after the operation (for donating the kidney). The results indicated a significant rise in the somatization subscale of the Middlesex Hospital Questionnaire (MHQ) from a mean of 1.61 to 3.23. There was no significant change in the other variables of these instruments or in the locus of control score. Only about one-fourth of the donors had prior knowledge of renal transplant. In almost all cases, the decision to donate had been voluntary and immediate, motivated by a concern for the recipient; there was virtually no second thoughts or regrets subsequently, which was apparently partly related to the opinions of other relatives who positively valued the act of donation.

Adult↗
PubMedDate not supplied

Social support, depression, and functional disability in older adult primary-care patients.

OBJECTIVE: The authors asked whether social support and depression are independently associated with functional disability and examined the potential role of social support as a moderator in the depression-functional disability association. METHODS: Subjects were 305 patients age 60 years and over. Predictor variables were social support, depressive symptoms, and depression diagnosis. Dependent variables were the Instrumental Activities of Daily Living Scale, the Physical Self-Maintenance Scale, and the Physical Functioning subscale of the Medical Outcomes Study 36-Item Short-Form Health Survey. Authors used multiple-regression analyses. RESULTS: Depressive symptoms and all dimensions of social support were independently associated with functional disability: the specifics of these relationships varied among types of social support and functional disability. Depression diagnosis was not independently associated with any functional disability measure. Social support (more instrumental help, more perceived satisfaction) moderated some depression diagnosis-functional disability associations, and one depressive symptom-functional disability association. CONCLUSIONS: The study hypotheses were partially confirmed. Different dimensions of social support have important and varied roles in the depression-functional disability dynamic. Future research is needed to further specify the complex relationships among depression, social support, and functional disability.

Activities of Daily Living↗
PubMedDate not supplied

A multicommutated flow system for determination of bismuth in milk shakes by hydride generation atomic fluorescence spectrometry incorporating on-line neutralization of waste effluent.

A highly sensitive method was developed for determination of bismuth in milk shakes by multicommutation hydride generation atomic fluorescence spectrometry (HG-AFS) based on off-line sonication for 10 min with aqua regia 8% (v/v) and on-line waste treatment. The instrumentation and chemistry variables were studied in order to provide the best performance. The limit of detection in the original samples, established for a probability level of 99.6% (k = 3), was 1.67 ng/g Bi. The method provides a fast alternative in control analysis with a sampling throughput of 72 h as compared with 31 h obtained by the classical continuous measurement. Additionally, multicommutation reduces waste generation by a factor of 2.6. The consumption of sample, reductant, and blank, as compared with continuous mode HG-AFS, was reduced 9.6, 4.5, and 13.3 times, respectively. To confirm the accuracy of the method, recovery studies were performed, and excellent agreement between multicommutation and continuous measurement-based values was obtained. Application of the developed methodology for bismuth determination in milk shake samples from the Spanish market provided concentrations ranging from 4.2 to 15.0 ng/mL, and good comparability with data obtained by continuous measurements after microwave-assisted total digestion of samples for a 95% probability level and 12 degrees of freedom was found.

Animals↗
PubMed2004

Anodic adsorptive stripping voltammetry of the antihypertensive drug candesartan cilexetil at a glassy carbon electrode.

The electrochemical behaviour of candesartan cilexetil (CND) was investigated in an acetonitrile: supporting electrolyte mixture (30% acetonitrile) in the pH range 1.5-11.00 by cyclic, linear sweep, differential pulse (DPV), adsorptive stripping differential pulse (AdSDPV), square wave (SWV) and adsorptive stripping square wave (AdSSWV) voltammetric techniques. CND exhibited one wave and one peak to the anodic direction. The oxidation process was found to be irreversible and adsorption controlled. To obtain good sensitivity, the instrumental and accumulation variables were studied using DPV and SWV techniques. Two linear calibration plots were obtained for both techniques. The detection limits were 9.15 x 10(-7) M and 7.94 x 10(-6) M for AdSDPV and AdSSWV, respectively. The method was validated and successfully applied for the analysis of CND tablets.

Antihypertensive Agents↗
PubMed2004

A nation-wide project for the revision of the Belgian nursing minimum dataset: from concept to implementation.

This paper describes the process of revising the Belgian Nursing Minimum Data Set (NMDS). The study started in 2000. Implementation is planned from 2006. The project is divided in 4 major phases. The first phase (June-October 2002) implied the development of the conceptual framework based on literature review and secondary data-analysis. The Nursing Interventions Classification (NIC) was selected as framework for the revision of the NMDS. The second phase focused on the language development (November 2002 - September 2003) with panels of clinical experts (N=75) for six care programs. They indicated hospital financing, nurse staffing allocation and assessment of the appropriateness of hospitalization as priorities of a revised B-NMDS. A draft instrument with 84 variables, using NIC, was developed during this period. This leads to an alpha version of a revised NMDS. The third phase (October 2003 - December 2004) focused on the data collection and validation of the new tool. The new NMDS was tested on 158 nursing wards in 66 Belgian hospitals from December 2003 until March 2004. This test generated data for some 95.000 inpatient days. The interrater-reliability of the revised NMDS is tested. The criterion-related validity of the revised NMDS is compared with the actual NMDS. The discriminative power of the revised NMDS is tested to select the most relevant items for data collection. This will result in a beta version of revised NMDS in December 2004. The records of the revised NMDS are linked with the hospital discharge dataset and other mandatory datasets to integrate the revised NMDS in the broader health care management. The fourth phase (January-December 2005) will focus on information management.

Belgium↗
PubMed2006

[Methodological design for the National Survey Violence Against Women in Mexico].

OBJECTIVE: To describe the methodology, the research designs used, the estimation and sample selection, variable definitions, collection instruments, and operative design and analytical procedures for the National Survey Violence Against Women in Mexico. MATERIAL AND METHODS: A complex (two-step) cross-sectional study was designed and the qualitative design was carried out using in-depth interviews and participant observation in health care units. RESULTS: We obtained for the quantitative study a total of 26 240 interviews in women users of health services and 2 636 questionnaires for health workers; the survey is representative of the 32 Mexican states. For the qualitative study 26 in-depth interviews were conducted with female users and 60 interviews with health workers in the States of Quintana Roo, Coahuila and the Federal District.

Battered Women↗
PubMedDate not supplied

Determination of size distribution of fat globules in intravenous fat emulsions by photon correlation spectroscopy.

A photon correlation spectroscopy method has been developed to characterize the size distribution of fat globules in intravenous fat emulsions (IFE) in terms of mean diameter, standard deviation of the distribution, and percentage of large particles outside the distribution. Mean fat globule diameters of samples of all IFE products available in Canada were about 0.3 microns, similar to values reported in the literature. The methodology is sufficiently sensitive to detect the presence of 5% by weight of 2 microns polystyrene microspheres in an intravenous fat emulsion. The effect of changes in instrument settings and variables on the results has been evaluated.

Fat Emulsions, Intravenous↗
PubMed1986

Mildly mentally retarded and nonretarded children's learned helplessness.

The relationship among four measures identified as operational definitions of learned helplessness was assessed in 44 mildly mentally retarded and 44 nonretarded children of equivalent mental age. Assessment of perseverance, response initiation, teacher perception of helplessness, and attributions for positive and negative achievement outcomes revealed an absence of corroboration in the two subgroups. The findings suggest that ability grouping and instrumentation are meaningful variables when evaluating learned helplessness in retarded and nonretarded students.

Child↗
PubMed1974

Contribution to the standardisation of a gas chromatographic method for the analysis of an oestrogenic and progestational combination.

An experimental procedure is described in order to standardize a gaschromatographic method proposed for a collaborative study organised by the F.I.P. Committee for Laboratories and Official Drug Control Services, on the analysis of some oestro-progestinic formulations. The assayed combination was a standard mixture of lynestrenol, mestranol and d, 1-alpha-tocopherol: testosterone was included as internal standard; two combinations, differing only in the internal standard content as specified in the text, were used. The variability of the instrumental factor was investigated performing some sets of single experiments, each consisting of 5 successive injections of the same standard mixture, on the same day. For each single experiment and for each substance the mean value Rm of the ratios R (R=area of the peak for compound cpi/area of the peak of the internal standard) was estimated with its relative standard deviation (% s.d.). For each set of experiments the % s.d. values were elaborated, following the Bartlett test, in order to obtain the sigma intra % value for each set, as a measure of the instrumental factor. An experimental evidence was observed for the relationship existing between the instrumental factor value (sigma intra %) and the internal standard content, in the operating conditions fixed for the present gas chromatographic analysis, a lowering of the instrumental factor beeing observed with the higher level of testosterone content (internal standard) in the mixture.

Chromatography, Gas↗
PubMedDate not supplied

Incentives for nurse employment.

This study was designed to discover perceived incentives for employment in terms of similarities in how employed and nonemployed nurses ranked employment inducements, and if the two groups could be differentiated on the basis of their rankings. March and Simon's (1958) theory was the basis for identifying inducements/incentives. A 47-item instrument was distributed randomly to a 5% sample of registered nurses (RNs) from a midwestern state. Similarities in incentives existed in the factor structure for both the employed and nonemployed. The factor structure for the part-employed approximated both groups depending on items considered. Little variance was accounted for by the instrument, indicating other variables need to be identified. Data indicate that the area of professionalism would be valuable in developing more items related to inducements/incentives.

Employment↗
PubMed1995

Health promotion services and evaluation in the workplace: pragmatic issues.

1. Nurses in the workplace can positively affect employee health and wellness, which ultimately affects productivity and profit. 2. Evaluative research about health promotion services provides useful data about programs and cost effectiveness. 3. Knowing the issues and variables affecting the provision of health promotion services and the evaluation of program outcomes helps nurses plan appropriate services and programs as well as valid and reliable research projects. 4. Major issues include: system entry, management support and commitment, environmental context, ethical considerations, program variables, research design, instruments and equipment, program sites and times, type of program/services, and recordkeeping.

Health Promotion↗
PubMed1993

Gender differences in the expression of depressive symptoms in middle adolescents: an extension of earlier findings.

Subjects in the present study were 153 French Canadian high school students (98 females, 55 males) participating in the second phase of a larger longitudinal study (Baron & Groulx, 1990; Baron, Régimbald, & Groulx, 1991). The purpose of this study was to investigate whether, consistent with the findings obtained at the first phase of the study, females maintain higher mean scores than do males on all items discriminating between groups on the basis of gender. Separate discriminant function analyses of both the Reynolds Adolescent Depression Scale (RADS) and the Beck Depression Inventory (BDI); items were consistent, with lower mean scores for males on all interpretable items. Results are discussed with respect to variability in the instruments, and in view of previous research aimed at examining the expression of depressive symptoms in this and other adolescent samples.

Adolescent↗
PubMed1993

Performance characteristics of fibrinogen assays. Results of the College of American Pathologists Proficiency Testing Program 1988-1991.

Plasma fibrinogen concentration appears to be an important risk factor for the development of atherosclerotic cardiovascular disease of a similar magnitude to cholesterol. The quality control of plasma fibrinogen assays has taken on new importance as a consequence of this potential role as an atherosclerotic risk factor. This article reviews the performance characteristics of 40,000 fibrinogen assays comprising the College of American Pathologists Proficiency Testing Program from 1988 through 1991. Instrument and reagent variables both play roles in the poor interlaboratory reproducibility documented by this study. The absence of either a national or international standard for plasma fibrinogen assays has been a major source of reagent variability. The validation and calibration of the College of American Pathologists lyophilized plasma reference preparation for fibrinogen determination is also reported in this study. The availability of this validated reference plasma should markedly improve interlaboratory reproducibility.

Analysis of Variance↗