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At least 271 records · Page 15Linked to original sources
PubMed1998

Rising incidence of non-Hodgkin's lymphoma in Spain: analysis of period of diagnosis and cohort effects.

Incidence trends in non-Hodgkin's lymphomas for the period 1973-1991 were studied using data from Spain's Zaragoza and Navarre registries. The overall rate of increase was 5.8% per year. Age-period-cohort models were used, also including sex and registry as explanatory variables. In these models, the variable period was categorized according to the observed changes in diagnostic availability during the length of the study. Non-Hodgkin's lymphomas increased with age, and rates were 31% lower in women. Incidence was almost 50% higher in Navarre, but differences in registry procedures might account for this discrepancy. The rise affects all adult age groups and seems to be the result of changes related not only to the period of diagnosis, mainly ascribable to improvements in diagnostic and coding practices, but also to the birth cohort. According to the model, the risk increased with on-coming generations at a rate of 1.5% per year. The AIDS epidemic in Spain is unable to explain this trend, although it may well exert a stronger influence in the future. Additional knowledge is required to understand the observed rise and to prevent the growing numbers of cases that are expected in years to come.

Adult↗
PubMed1992

The EEG of the sleep onset period in insomnia: a discriminant analysis.

A period of rapid change in the wave components of the electroencephalogram (EEG) marks the transition from wake to sleep. Twenty-six insomniac and 28 control nights were studied in a discriminant analysis to determine whether this transitional state is modified in any way in subjects diagnosed for psychophysiological insomnia. A discriminant function was derived based on 20 insomniac and 22 normal nights. All 42 nights were correctly classified by this function. The sleep onset period, extending on the average over about 3 minutes, was characterized essentially by the beta and delta components of the EEG signal and by an activity index given by the ratio beta/delta, measured at the temporal lobe sites. Other variables included the subject's age and the magnitude of the changes occurring in the difference between activities in the right and left hemispheres. The variables contributing most to the discrimination were the activity index and beta, especially at the transitions from wake to stage 1 and from stage 1 to stage 2. The contribution of delta to the discrimination was less, but extended further in time to include stage 2 sleep. A test on the remaining six insomniac and six control nights gave a 75% classification accuracy, thus validating the derived discriminant function.

Adolescent↗
PubMed2006

Health effects of ultraviolet irradiation in asthmatic children's homes.

OBJECTIVE: Centrally installed ultraviolet (UV) irradiation units were investigated to determine the potential health benefits in mold-sensitized asthmatic children. METHODS: Nineteen mold-sensitized asthmatic children 5 to 17 years of age with home central ventilation systems were enrolled in a 28-week double-blinded placebo controlled cross-over trial. Clinical outcome measurements included morning and evening peak expiratory flow rates (PEFR), PEFR variability, change in forced expiratory volume in 1 second (FEV1), change in total rhinoconjunctivitis and asthma symptom scores, change in rhinoconjunctivitis and asthma quality-of-life scores, and total (rescue and controller) medication use from baseline and between time periods. Environmental outcomes included changes in temperature, relative humidity, dew point, and indoor airborne mold and bacterial counts from baseline and between time periods. Analysis of variance (ANOVA) and regression analysis and t test were used to evaluate relationships between environmental exposure(s) and clinical outcome measurements during each study period. RESULTS: Twelve male and seven female children, average age 10.6 years, were enrolled. A statistically significant improvement in PEFR variability in subjects receiving CREON2000 units followed by placebo units was observed (p < 0.05) across both treatment periods. Within group analysis during treatment period 1, a statistically significant improvement in reduction of asthma symptom scores, the number of days with asthma symptoms, total asthma medication use, and PEFR variability were observed in subjects receiving CREON2000 units versus placebo units (p < 0.05). No significant differences were observed between the CREON 2000 and placebo units for other clinical or environmental outcome measurements. CONCLUSIONS: Central UV irradiation was effective at reducing airway hyperresponsiveness manifested as PEFR variability and some clinical symptoms. A larger cohort controlled longitudinal study to validate the clinical health effects of UV irradiation as a primary indoor environmental intervention for allergic asthma is necessary to confirm this finding.

Adolescent↗
PubMed1987

Discrimination and spectral resolution of ultradian and circadian periodicities for 24-hour blood pressure patterns on sodium manipulation in normotensive humans.

The effects of a severe (10-20 mEq/24-h) but short-term (7-days) restriction in dietary sodium on 24-h blood pressure (BP) patterns were investigated in 20 normotensive volunteers (10 men, 10 women; 20-25 years old) by means of non-invasive automatic sphygmomanometric monitoring (recordings at 1-h interval) at home, with subjects in bedrest. Statistical methods used include bivariate Gaussian distribution analysis for systolic and diastolic BP bivariate discriminant analysis, periodic regression analysis with a 24-h period (cosinor method) and spectral analysis of time series. Casual BP measurements were unable to detect the tensinogenic effects, while the bivariate Gaussian analysis documented a total rearrangement in the pattern distribution to show discriminated values of BP after sodium restriction. A significant decrease (p less than 0.01) in the 24-h mean level (mesor) for systolic BP was observed. An increase in the extent of fluctuation (amplitude) for the circadian components was documented by the spectral analysis, mainly in diastolic BP patterns. Such a phenomenon of 'amplitude magnification' was not accompanied by a change in the repartition of the ultradian and circadian harmonic components. The extensive changes in the time structure support the hypothesis of an interaction of sodium regimen with the centrally-located oscillators which physiologically organize the circadian rhythmicity of BP.

Adult↗
PubMed1989

Mortality of coronary artery bypass grafting before and after the advent of angioplasty.

In an effort to determine whether the population of patients undergoing isolated coronary artery bypass grafting and the outcome of these operations have changed, we analyzed the records of two patient populations from our institution. Interventional cardiology techniques (angioplasty, thrombolysis) were not used at our institution before 1982. The records of 736 patients (group 1) who underwent isolated coronary artery bypass grafting from January 1975 to July 1981 were reviewed and compared with a group of 603 patients (group 2) who underwent operation from July 1985 to December 1987. The techniques of operation and myocardial preservation were virtually identical during the two periods. During the group 2 analysis period, 343 angioplasty procedures were performed. The patients in group 2 were significantly older, had increased preoperative New York Heart Association classification, had sustained more previous myocardial infarctions, and had more associated morbid medical conditions. There was a threefold increase in patients seen for reoperative revascularization procedures and a fourfold increase in emergency operations. Overall mortality, although not significantly different, did increase slightly from 2.69% in group 1 to 3.83% in group 2. Mortality after elective procedures remained essentially unchanged (2.05% for group 1 and 1.90% for group 2).

Aged↗
PubMed2006

Healing of subacute tympanic membrane perforations in chinchillas treated with epidermal growth factor and pentoxifylline.

HYPOTHESIS: The aims of the present study were to determine the effect of epidermal growth factor (EGF) and pentoxifylline on subacute tympanic membrane (TM) perforations and to quantify the healing rate of such perforations treated with these drugs alone or in combination. BACKGROUND: It is known that EGF modulates in vitro and in vivo proliferation of epithelial and endothelial cells. Pentoxifylline is a methylxanthine that has been used to treat experimental skin flaps and venous leg ulcers. Data in the literature regarding this subject are contradictory, and quantitative data regarding the effects of EGF and pentoxifylline on TM perforation healing are scarce. METHODS: We studied 50 chinchillas submitted to TM perforation. On postoperative Day 30, eight were selected for histologic analysis. Of the remaining 42, those presenting little or no healing were distributed into four groups: control, EGF, pentoxifylline, and EGF combined with pentoxifylline. RESULTS: Histologic analysis showed that the observation period adopted was sufficient to consider the TM perforations subacute. We found significant differences between the study groups and the control group in the healing rate of subacute TM perforations during a 30-day period (analysis of variance; p < 0.001), which was 30.3% for the EGF group, 3.6% for the pentoxifylline group, 16.5% for the EGF-pentoxifylline group, and 8.7% for the control group. CONCLUSIONS: The use of EGF promoted healing of subacute TM perforations in chinchillas, and the use of pentoxifylline did not. The combination of the two had no synergistic effect on the healing of these perforations.

Analysis of Variance↗
PubMed1970

Cell proliferation in human melanoma.

The cytokinetics of subcutaneous metastases in five patients with melanoma was studied. Multiple simultaneous biopsies following pulse labeling with tritiated thymidine were performed in one patient. There was relatively uniform labeling and mitotic indices among these. Within the individual tumors, there was some variation in the labeling index with small clusters of tumor cells having significantly higher labeling indices than more sparsely infiltrating tumor cells. Repetitive biopsies following pulse labeling were performed in two patients. The per cent labeled mitosis curves were similar in the two patients. By computer analysis a median G(2) period of 5.3 hr and an S period of 21 hr were obtained. The generation time (T(e)) was highly variable with a median of 3 days. This T(e) was consistent with that calculated from grain count studies in these patients. Two patients received either intermittent or continuous tritiated thymidine over a 10-20 day period. Analysis of the labeling index curve by computer fitting indicated a growth fraction of 20-30%. The growth fraction calculated by other indirect methods was consistent with the computer analysis. The potential tumor doubling time as calculated from the T(e) and growth fraction was much shorter than the actual doubling time indicating that cell loss was approximately 70% of the rate of cell production.

Adult↗
PubMed1996

The structure of the exopolysaccharide produced by the halophilic Archaeon Haloferax mediterranei strain R4 (ATCC 33500).

The halophilic Archaeon Haloferax mediterranei exudes into the growth medium a high molecular weight sulfated polysaccharide. The structure of the repeating unit of this polymer was determined by a combination of glycose, methylation, and sulfate analysis, periodate oxidation, and 1D and 2D NMR spectroscopic analysis of the native and periodate-oxidised/reduced polysaccharides. The location of the sulfate group was established from the 1H and 13C NMR data. The structure of the repeating unit of the polysaccharide may be written as [formula: see text]

Acetylglucosamine↗
PubMed1984

[Description of a marital mobility model and its application to Quebec].

"The marital mobility model allows for the simultaneous study of the formation and break-up of couples in a given cohort. The model is equally suited for longitudinal and for period analysis. Its essential feature is the construction of a multiple status life table that deals either with initial status changes or with successive ones. Preliminary results obtained for Quebec indicate that, in recent generations, individuals marry less and divorce more; at the same time the prevalence of cohabitation and the number of births out of wedlock both continue to increase." (summary in ENG, SPA)

Americas↗
PubMed1992

[Approaches and methods of fertility estimation in demographic projections].

The author describes methods of fertility estimation within demographic projections. He concludes that both period analysis and cohort follow-up are important to a thorough study of the birth rate of a population. "The second part of the article is dedicated to the procedures used for disaggregating the integral [of] full fertility, and extrapolating the incompleted fertility of a given cohort when formulating birthrate hypotheses." The geographical scope is worldwide. (SUMMARY IN ENG AND RUS)

Birth Rate↗