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At least 343 records · Page 19Linked to original sources
PubMed2000

Quality control of cancer screening examination procedures in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

Investigators for the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial describe quality control procedures for the digital rectal examination, ovarian palpation examination, transvaginal ultrasound, chest X-ray, and flexible sigmoidoscopy. These cancer screening tests are subjective and difficult to standardize. PLCO quality control procedures aim to measure and, where possible, reduce variation, across examiner and screening center, with respect to cancer screening test performance. Initial protocols stressed examiner qualifications, experience, and training; equipment specifications; examination procedures; and definitions for positive tests. The PLCO quality assurance subcommittee developed a final quality assurance plan, which included central approval and registration of PLCO examiners, direct observation of screening test performance during periodic site visits by the National Cancer Institute and coordinating center auditors, periodic analysis of screening test data, and procedures for independently duplicating or reviewing selected examinations. For each modality, the periodic data analyses examine the test-positive and the test-inadequate proportions and aim to identify divergent centers or examiners. Procedures for duplicating examinations specify feasible sample sizes for precise estimates of agreement between examiners, at each center, for each screening test modality, and over a 1-year period. These quality control procedures will help characterize the consistency and reliability of the PLCO cancer screening tests.

Aged↗
PubMed1995

Automated approaches to rapid-response testing. A comparative evaluation of point-of-care and centralized laboratory testing.

This study evaluates the premise that point-of-care or near-patient testing provides more effective medical care because laboratory turnaround time is reduced and, therefore, presumably the time before therapy begins is reduced. An accurate evaluation of this premise must compare the operation of a point-of-care laboratory and an alternative dedicated, centralized laboratory. Assessment of both laboratory operations with respect to turnaround time, costs and benefits, regulatory factors, and finally patient care outcome are all essential in reaching a conclusion. In this study, laboratory operations in a centralized urgent care laboratory were compared with those of a point-of-care satellite laboratory. Turn-around time analysis for whole blood (heparinized specimens requiring no centrifugation) and serum analytes were measured during a representative time period. Analysis of turnaround time considered both the preanalytic time, defined as collection to receipt of the specimen in the laboratory, and the analytic time component that accounts for receipt, processing, analysis, and reporting of the final data into the laboratory information system. The preanalytic component of the point-of-care satellite laboratory was also compared with the urgent care laboratory equipped with a rapid-transport specimen system. Turnaround time in the point-of-care satellite laboratory and urgent care laboratory equipped with a rapid-transport specimen system. Turnaround time in the point-of-care satellite laboratory and urgent care laboratory equipped with a rapid-transport system were comparable. In this analysis, staff requirements, ability to comply with regulatory requirement, and the increasing demand for a larger selection of tests needed urgently were considered. In a tertiary care medical center, such as the authors', a dedicated, centralized laboratory equipped with a rapid-transport specimen system provides better comprehensive laboratory service than does a point-of-care facility with limited capability.

Automation↗
PubMed1997

Anthropometric and quantitative EMG status of femoral quadriceps before and after conventional kinesitherapy with and without magnetotherapy.

The frequency of femoral quadriceps muscle hypotrophy has become a significant therapeutic problem. Efforts are being made to improve the standard scheme of kinesitherapeutic treatment by using additional more effective therapeutic methods. Beside kinesitherapy, the authors have used magnetotherapy in 30 of the 60 patients. The total of 60 patients, both sexes, similar age groups and intensity of hypotrophy, were included in the study. They were divided into groups A and B, the experimental and the control one (30 patients each). The treatment was scheduled for the usual 5-6 weeks. Electromyographic quantitative analysis was used to check-up the treatment results achieved after 5 and 6 weeks of treatment period. Analysis of results has confirmed the assumption that magnetotherapy may yield better and faster treatment results, disappearance of pain and decreased risk of complications. The same results were obtained in the experimental group, only one week earlier than in the control group. The EMG quantitative analysis has not proved sufficiently reliable and objective method in the assessment of real condition of the muscle and effects of treatment.

Adolescent↗
PubMed2004

Reduced joint pain after short-term duodenal administration of seal oil in patients with inflammatory bowel disease: comparison with soy oil.

BACKGROUND: Rheumatic joint pain is a common extra-intestinal complication of inflammatory bowel disease (IBD). Because the high ratio of n-6 to n-3 fatty acids (FAs) of the Western diet might promote rheumatic disorders, we sought to compare the effects of short-term duodenal administration of n-3-rich seal oil and n-6-rich soy oil on IBD-related joint pain. METHODS: Nineteen patients with IBD-related joint pain were included in the study; 9 had Crohn disease and 10 had ulcerative colitis. Ten millilitres seal oil (n = 10) or soy oil (n = 9) was self-administered through a nasoduodenal feeding tube 3 times daily for 10 days. RESULTS: Compared with soy oil treatment, seal oil significantly reduced the duration of morning stiffness (P = 0.024), number of tender joints (P = 0.035), intensity of pain (P = 0.025) and the doctor's scoring of rheumatic disease activity (P = 0.025) at the end of the 10-day treatment period. Analysis of the effects as area under the curve (area between the curve and baseline, zero) for the entire period from start of treatment until 6 months' post-treatment suggested a long-lasting beneficial effect of seal oil administration on joint pain, whereas soy oil tended (not significantly) to aggravate the condition. Consistently, the serum ratios of n-6 to n-3 FAs (P < 0.01) and arachidonic acid to eicosapentaenoic acid (P < 0.01) were reduced after treatment with seal oil. CONCLUSION: The results suggest distinctive, differential prolonged effects on IBD-related joint pain of short-term duodenal administration of n-3-rich seal oil (significant improvement) and n-6-rich soy oil (tendency to exacerbation).

Adolescent↗
PubMedDate not supplied

Tolmetin in osteoarthrosis of the hip and knee: double-blind crossover trials.

A double-blind crossover study was carried out in 24 patients with osteoarthrosis of the hip or knee to compare the efficacy of a 1200 mg tolmetin daily dose with a 600 mg daily dose, each given for 2 weeks. Both regimens were well tolerated and appeared to give satisfactory relief of pain, but no differences in response between the two dosages were noted either because the number of patients involved were small or because the methods of monitoring clinical improvement were not sufficiently sensitive. A further double-blind crossover study was carried out in 40 patients to compare the efficacy of 1200 mg tolmetin daily with 150 mg ketoprofen daily, each drug being given for 2 weeks after an initial 1-week period on placebo. Pain was monitored using a visual analogue line technique and significant differences were found between both active and placebo periods. Analysis of the biochemical monitoring of both trials showed statistically significant rises in blood urea for all active treatment periods. There were no concomitant changes in serum creatinine, suggesting this effect to be extra-renal in origin. In general, side-effect incidence was low; 1 patient withdrew from ketoprofen treatment because of weight increase and urine retention.

Clinical Trials as Topic↗
PubMed2003

Correlation of phasic and tonic skin-conductance responses with severity of motion sickness induced by viewing an optokinetic rotating drum.

50 subjects viewed an optokinetic rotating drum for 12 min. Subjective ratings of motion sickness were obtained during the development of motion sickness. The tonic and phasic skin-conductance responses were recorded from the sites of finger, palm, and forehead during the baseline and drum-rotation periods. Analysis showed subjects' subjective ratings of motion sickness gradually increased during the 12 min. of the drum-rotation period. Both phasic and tonic skin conductance also gradually increased during drum rotation for all subjects. Pearson correlations for 50 subjects showed their ratings of motion sickness during the drum-rotation period were significantly correlated with ratios of phasic skin conductance recorded at the forehead between drum rotation and baseline periods (r = .62), followed by ratios of tonic skin conductance recorded at the finger palmar site (r = .48), ratios of phasic skin conductance recorded at the finger palmar site (r = .43), and ratios of tonic skin conductance recorded at the forehead site (r = .39). In conclusion, the phasic skin-conductance responses recorded at the forehead site were most sensitive physiological correlates of motion sickness induced by viewing an optokinetic rotating drum.

Adolescent↗
PubMed2000

HIV-associated tuberculosis in the era of highly active antiretroviral therapy. The Adult/Adolescent Spectrum of HIV Disease Group.

OBJECTIVE: To determine the effect of highly active antiretroviral therapy (HAART) on the risk of tuberculosis (TB) among persons infected with the human immunodeficiency virus (HIV), and to examine trends in TB. METHODS: For the risk factor analysis, we examined data from the Adult/Adolescent Spectrum of HIV Disease (ASD) project from January 1996 through June 1998. ASD is an observational cohort study conducted in over 100 clinics and hospitals in 11 US cities. Poisson regression was used to model the incidence of TB while controlling for HIV-exposure mode, race, country of birth, CD4 count, TB preventive therapy, and half-year of diagnosis. We also examined trends in TB incidence January 1992 to June 1998. RESULTS: During the risk factor analysis period, 80 cases of TB occurred in 16,032 person-years (5.0 cases/1000 person-years). In multivariate analysis, the risk of TB was much lower among persons prescribed HAART (RR = 0.2, 95%CI 0.1-0.5, P < 0.001), and also lower among persons prescribed other antiretroviral therapy (RR = 0.6, 95% CI 0.4-1.0, P = 0.05), than the risk in persons not prescribed antiretroviral therapy. In addition, TB rates declined from January 1992 to June 1998 (P < 0.001). CONCLUSION: Widespread use of HAART reduced the risk for TB and may help bring about further declines in TB among persons infected with HIV.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Injuries with biological risk in a major hospital: analysis of a caseload].

This article report preliminary data on injuries involving risks from biological agents occurred in healthcare workers of a major hospital over a 5-years period ('96-'00). The role of Occupational Competent Physician is underlined. Injuries' database, archives of occupational diseases, discharge diagnosis and notification of transmissible infectious diseases were consulted. 200 injuries (3/4 percutaneous) were on average registered yearly, with a decreasing trend. Subjects had a mean age of 34 years and 7 years of length of employment at the hospital. 60% of exposures occurred in nurses and 43% workers belonged to surgical areas. Serological data of the "source patients" were available for 1/3 of the cases and 35% of them were bloodborne viruses infected; 1 seroconversion for HCV was registered. On the whole, our results are similar to data from national and international literature. However a few factors limited the data collection and interpretation, mainly the lack of computer formats and different ways of coding and filing the information. The periodical analysis of injuries is useful to the Occupational Physician, particularly for educational intervention and sanitary surveillance of workers. Moreover, the Occupational Physician plays an important role in injuries prevention, especially in spreading the information on Standard Precautions, evaluating the human factor, reducing the "under-reporting" of accidents, counselling, evaluating prognosis and resuming work.

Accidents, Occupational↗
PubMed2004

Determination of nitrogen-fixing phylotypes in Lyngbya sp. and Microcoleus chthonoplastes cyanobacterial mats from Guerrero Negro, Baja California, Mexico.

In many environments, biological nitrogen fixation can alleviate nitrogen limitation. The high rates of N(2) fixation often observed in cyanobacterial mats suggest that N(2) fixation may be an important source of N. In this study, organisms expressing nifH were identified in a Lyngbya sp.- and two Microcoleus chthonoplastes-dominated cyanobacterial mats. The pattern of nitrogenase activity was determined for the Lyngbya sp. mat and a Microcoleus chthonoplastes mat sampled directly in Guerrero Negro, Mexico. Their maximum rates were 23 and 15 micro mol of C(2)H(4) m(-2) h(-1), respectively. The second Microcoleus mat, which was maintained in a greenhouse facility, had a maximum rate of 40 micro mol of C(2)H(4) m(-2) h(-1). The overall diel pattern of nitrogenase activity in the three mats was similar, with the highest rates of activity occurring during the dark period. Analysis of nifH transcripts by reverse transcription-PCR revealed that several different organisms were expressing nifH during the dark period. nifH phylotypes recovered from these mats were similar to sequences from the unicellular cyanobacterial genera Halothece, Myxosarcina, and Synechocystis, the filamentous cyanobacterial genera Plectonema and Phormidium, and several bacterial nifH groups. The results of this study indicate that several different organisms, some of which were not previously known to fix nitrogen, are likely to be responsible for the observed dark-period nitrogenase activity in these cyanobacterial mats.

Base Sequence↗
PubMed1991

Endocytosis of immunotoxin-791T/36-RTA by tumor cells in relation to its cytotoxic action.

Ricin A chain immunotoxin constructed with monoclonal antibody 791T/36, which recognizes a tumor associated glycoprotein Mr 72,000 antigen present on sarcomas and colon and ovarian cancer cells, is cytotoxic for cell lines from tumors expressing this antigen. Incubation of sarcoma 791T cells with immunotoxin for only 5 min is sufficient to produce greater than 95% inhibition of tumor cell growth. Papain treatment of these cells to remove immunotoxin from the cell surface indicated that the cell surface acts as a reservoir for continued internalization of immunotoxin over several hours, but even so, 50% inhibition of cell survival was produced over a 2- to 3-h period. Analysis of the rate of endocytosis demonstrated that 30-50% of cell bound immunotoxin was internalized over a 180-min period. This was primarily dictated by the antibody moiety, regardless of the degree of conjugation to ricin A chain. This rate is much slower than that of other cell surface ligands such as transferrin. Cell cytosol acidification experiments were performed to determine whether this immunotoxin was internalized by clathrin coated pits, which is relatively rapid, or by smooth pits, which is slower, and the results indicated the latter mechanism is almost exclusively used. Intracellular trafficking of antibody 791T/36, conjugated to human serum albumin-tetramethylrhodamine was investigated by flow cytometry. The movement of the conjugate into the lysosomal compartment was delayed so that degradation products were only detected after a lag phase of 30-60 min. The lack of potentiator dependence of 791T/36 immunotoxin is in keeping with these findings.

Ammonium Chloride↗
PubMed1983

[Comparison of the anti-arrhythmic effects of propafenone and aprindine in the treatment of refractory chronic ventricular arrhythmias. A randomized double-blind crossover study controlled with placebo].

A placebo-controlled, randomized, double-blind, crossover study was performed in 14 patients with chronic, resistant, ventricular arrhythmias in order to evaluate the efficacy and safety of two new antiarrhythmic agents, propafenone and aprindine. After an initial placebo phase, patients received orally either propafenone (600 mg daily) or aprindine (150 mg daily for the first two days and 50 mg every 12 hours successively) for five days. This treatment was followed by a drug-free period (placebo II); patients were then crossed over to the alternative drug. A 24-hour Holter recording was performed during the last 48 hours of the initial placebo phase and on the final day of each phase of the crossover period. Analysis of Holter recordings revealed that the mean hourly PVCs frequency, for the group, was similar during the two control periods. Significant reduction in the mean hourly frequency of PVCs from control levels was observed in 78% of the patients during propafenone therapy and in 42% during aprindine therapy. For the whole group, propafenone induced a significant reduction of the average PVCs/h frequency (p less than 0.05), whereas the aprindine was ineffective. Finally no patient experienced side effects with propafenone, whereas aprindine caused side effects in three patients (dizziness, tremor, ataxy).

Adult↗
PubMed1995

A cross-over study comparing the efficacy of a combination of atenolol and nifedipine at different doses in angina pectoris.

Although the combined administration of atenolol and nifedipine has been shown to be effective in the treatment of angina pectoris the optimum dosage level of the combination has not yet been established. A double-blind, randomly assigned three period cross-over study was carried out therefore to investigate the effects of different daily doses of a fixed combination of 50 mg atenolol and 20 mg sustained-release nifedipine per capsule. Twenty-one patients with stable angina pectoris were randomized, after a 2-week run-in period, to receive treatment for 4 weeks with either 1 capsule twice daily (A), 2 capsules in the morning and 1 in the evening (B), or 2 capsules twice daily (C). A treadmill exercise tolerance test was performed together with a clinical evaluation after the run-in and each of the three treatment periods. Analysis of the results from the 19 patients who completed the study revealed there were no significant differences between the three treatment periods with respect to the general exercise test parameters, number of anginal attacks per week or nitrate consumption. Few side-effects were reported and were only mild in nature. On these findings, therefore, there would appear to be little justification for increasing the dose of the combination above the equivalent of treatment A.

Adrenergic beta-Antagonists↗
PubMed1994

Interrelation between stress and coaches' behavior during rest periods.

The purpose of the present investigation was to examine the interrelation between stress and coaches' behavior during rest periods. Subjects were 154 German coaches who completed the Rest Period Questionnaire and a Bibliographic Questionnaire for Coaches designed to attribute stress to coaches' behavior during rest periods. Analysis indicated that coaches who are highly stressed by the practice rate themselves significantly less active and less authoritarian during rest periods than do their low stressed colleagues. In addition, coaches who are highly stressed by the competition rate themselves significantly less warm-hearted than the low stressed group.

Adult↗
PubMed1998

Evidence of phase transitions in heart period dynamics.

Complexity measures of non-linear dynamics are a useful tool for quantifying observed stretching, folding, scaling and mixing processes in the Takens-reconstructed state space of heart period dynamics. Although such measures are not suited to provide evidence of deterministic chaos or to estimate true fractal dimensions and Lyapunov spectra in heart period time series, they allow the classification of RR dynamics and the identification of changes in RR complexity (RRC). The aim of this study was to develop appropriate measures and examine their utility in identifying the physiological effect of changes between the sleeping and waking state. Twenty-four hour electrocardiography (EEG) recordings and diaries noting their waking/sleeping period were obtained from 78 healthy subjects, aged 20 to 55 years. The approximate information dimension (ApD1) and the approximate Kolmogorov entropy (ApEn), introduced by Pincus, Kaplan and others, were modified in order to allow the calculation of strictly local values. That is, the local or pointwise dimensions and entropies were calculated for each reference vector with respect to its symmetric neighbourhood in time. For each subject the values for the local measures were averaged for 10-min periods, resulting in 144 global values over 24 h. Similarly, low- and high-frequency spectral parameters were calculated. All measures were examined and compared for the waking and the sleeping periods. All complexity measures as well as to a lesser degree high-frequency power showed a linear dependency on mean RR interval with a large individual variation. For the RRC measures this linear correlation was separated into two different clusters corresponding to the sleeping and waking periods. In almost all cases the correlation was greater in the waking period. In particular, in many cases no correlation was observed in the sleeping period. However, the r values for LF were appreciably lower and indicated solely a weak relationship to the RR interval in the waking period. Analysis of variance combining mean RR interval with RRC or spectral parameters singly and in couples revealed that the best separation with respect to physiological state could be achieved with the complexity measures, in particular with ApEn. The results show evidence of at least two dynamical regimes (phases) of heart period dynamics and a close but different functional relationship within the phases between RR interval and RR complexity. The separation between these regimes and the relatively sudden shift from one regime to the other suggest the existence of a phase transition with respect to waking and sleeping periods in terms of synergetics.

Adult↗
PubMed1975

Human sleep and EEG through a cycle of methadone dependence.

The effects of oral methadone on EEG and sleep were studied in 6 male postaddicts. Continuous nocturnal measurement of EEG, EMG and EOG was used to define sleep patterns. Period analysis and power spectral analysis were performed on each 8 min sample of daytime (eyes closed) EEG. Both sleep and EEG were studied during a predrug control period, during the methadone induction phase (45-60 mg/day), stabilization phase (100 mg/day), and then 6; 10, 13, 18 and 22 weeks after withdrawal. One subject did not complete the last two withdrawal sessions. While on methadone, subjects reported that they slept more and also showed an increase in slow wave activity and a decrease in fast wave activity of their EEG during this time. Nocturnal sleep was not markedly altered during the chronic administration of methadone. Subjects reported an increase in dreaming soon after withdrawal, and then 3-5 weeks of nocturnal isnomnia. At the 6th week after withdrawal, slow wave activity in the daytime EEG was decreased, fast wave activity was increased, and mean EEG frequency was increased. REM sleep and delta sleep were increased during withdrawal. These data provide further evidence that chronic administration of narcotic analgesics may induce persistent functional changes in the central nervous system.

Adult↗
PubMed1989

Unchanging clinical picture of coeliac disease presentation in Campania, Italy.

Four hundred and sixty-three new diagnoses of coeliac disease in children were made during 1973 to 1986 in our department. The distribution of new diagnoses per year did not show any decreasing trend in the period 1973 to 1986. No changing trend in breast feeding attitudes was found in the region during the same period. Analysis of the clinical pattern showed a constant distribution of age at diagnosis, onset of first symptoms and nature of symptoms throughout the period studied. These data suggest that coeliac disease is predominantly genetically determined and its expression is modulated by individual and environmental factors. The stability of the observed prevalence of the disease is parallel to the unchanging pattern of breast feeding attitudes in the region.

Adolescent↗
PubMed1985

Longitudinal study of dental caries in individuals in Jönköping, Sweden, aged 15 years in 1973 and 20 years in 1978.

The aim of this investigation was to study caries development between the ages of 15 and 20 yr in the same individuals. Data concerning 100 adolescents constituted the basic material. Eighty subjects could be re-examined 5 yr after the first examination. The mean number of teeth per subject was 27.1 both in 1973 and in 1978. Four subjects (4%) in 1973 and three subjects (2.4%) in 1978 showed no decayed and/or filled proximal tooth surfaces. The prevalence of intact tooth regions was higher in the mandible than in the maxilla. Only one of the 73 subjects who were free from caries in the mandibular incisor/canine region at the basic examination developed new carious lesions in this region during the next 5-yr period. Analysis of the frequency distribution of the different caries diagnostic groups revealed that 32 subjects (40%) showed no change during the 5-yr period while 47 (58.7%) now belonged to a higher caries prevalence group. 3538 (80.7%) proximal surfaces were diagnosed as intact at the basic examination. The number of intact surfaces 5 yr later was 3107 (70.9%). In individuals with low and high numbers of decayed and/or filled surfaces, respectively, there was a tendency towards a more pronounced individual caries progression in the group that showed the highest caries prevalence at the basic examination than in the group showing a low caries prevalence.

Adolescent↗
PubMed2003

Power spectrum ranked independent component analysis of a periodic fMRI complex motor paradigm.

Independent component analysis (ICA) has been demonstrated to be an effective data-driven method for analyzing fMRI data. However, a method for objective differentiation of task-related components from those that are artifactually non-relevant is needed. We propose a method of constant-cycle (periodic) fMRI task paradigm combined with ranking of spatial ICA components by the magnitude contribution of their temporal aspects to the fundamental task frequency. Power spectrum ranking shares some similarity to correlation with an a priori hemodynamic response, but without a need to presume an exact timing or duration of the fMRI response. When applied to a complex motor task paradigm with auditory cues, multiple task-related activations are successfully identified and separated from artifactual components. These activations include sensorimotor, auditory, and superior parietal areas. Comparisons of task-related component time courses indicate the temporal relationship of fMRI responses in functionally involved regions. Results indicate the sensitivity of ICA to short-duration hemodynamics, and the efficacy of a power spectrum ranking method for identification of task-related components.

Acoustic Stimulation↗