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PubMed1990

Heart rate variability and sudden infant death syndrome.

The sudden infant death syndrome (SIDS) is the most common cause of death in infancy. The pathophysiological mechanism leading to SIDS is still obscure. In the QT hypothesis, the mechanism must be an arrhythmogenic sympathetic imbalance: the infants die suddenly of cardiac arrhythmia. Recently, it has been suggested that analysis of heart rate variability (HRV), expressed as standard deviation or variance analysis, can provide adequate information on sympathovagal interaction. We studied 150 newborns enrolled in a previous prospective electrocardiographic study to evaluate the predictive value of QT interval for SIDS. We analyzed the ECGs recorded with infants alert on the fourth day of life and after 2 months. For each ECG, the HRV was calculated using the first standard deviation of of RR intervals (ms) measured for 1 minute. The average RR interval was 441 +/- 71 ms at the fourth day and 410 +/- 39 ms at the second month. The QTc and HRV mean values were 396 +/- 23 and 23 +/- 12 ms at the fourth day, 412 +/- 19 and 15 +/- 7 msec at the second month. Therefore, the SD values of heart rate were correlated with QTc in order to assess a possible relationship between the two variables. The correlation coefficient and regression equation were: -0.639 and y = 423.67 - 1.18*X (P less than 0.001) at the fourth day, -0.146 and y = 418.09 - 0.37*X (NS) at the second month. In conclusion, our data seems to confirm a delayed maturation or impaired functioning of the autonomic nervous system in the first weeks of life, reflecting a direct correlation with QT prolongation.

Electrocardiography↗
PubMed1993

Self blood pressure measurement at home.

Forty-six untreated patients measured their blood pressure at home for three weeks using an A and D, UA 751 automatic device, and were examined three times at the outpatient clinic. Home blood pressure was significantly lower than clinic blood pressure, even at the third visit when the correlations between clinic and home values were the most significant. The differences between clinic and home values had a gaussian distribution. The variance analysis of home blood pressure values showed that 67% of the variance was attributable to the between-subject component, 2% to the day effect, 15% to the time of the day effect and 16% to the residual (the measurement error). The standard deviation of the difference between two five-day periods of self blood pressure monitoring at home (5.4 and 4.1 mm Hg) was much lower than what has been reported for clinic measurements or 24-hour ambulatory monitoring.

Adult↗
PubMed2000

[Determination of major components in liuyingwan pills by supercritical fluid extraction(SFE)].

OBJECTIVE: On the basis of SFE and CGC to establish a method for the qualitative and quantitative analysis of major components in Liuyingwan pills. METHOD: Orthogonal design and variance analysis were used to optimize the four variables (temperature, pressure, volume of modifier and static extraction time) of SFE, and the quantification was completed by CGC. RESULT: The optimized conditions are as follows: pressure 48.2 MPa, temperature 60 degrees C, 0.2 ml ethyl acetate as modifier and static extraction 10 min. The recoveries of borneol and eugenol are 101.93% (RSD 1.56%) and 98.43% (RSD 2.26%) respectively. CONCLUSION: Compared with conventional methods, SFE is rapid, convenient and accurate in determining borneol and eugenol.

Camphanes↗
PubMed1994

Comparison of manual and computer-assisted automatic measurements of wall thickness of the left ventricle in two-dimensional echocardiography.

To investigate the clinical applicability of automatic analysis of wall thickness in two-dimensional echocardiography, computer-assisted and conventional manual methods were compared in 26 cases. An echo threshold was automatically set in short-axis echo images through a discriminatory variance analysis of the signal-to-noise ratio. A fixed standard was determined inside the left ventricle using the circle window method, which we developed previously. Two abrupt echo reflections were selected as candidate points for the borders, and an outward search was conducted in all directions from a fixed standard to separately delineate the endocardial and epicardial interfaces. Interpolation using a spline function was applied to these points to complete the border lines. Differentiation was also used to eliminate the anterior and posterior papillary muscles. Significant correlations of r = 0.98 were found between the computer and manual assessments of the epicardial and endocardial intraluminal ventricular areas (p < 0.01). A correlation of r = 0.87 was also obtained for myocardial wall thickness as determined by the 2 methods (p < 0.01). Variability of the reproducibility using the computer method was 0.22% for the epicardial area and 0.64% for the endocardial area. These results confirm that computer-aided automatic measurement of wall thickness is clinically applicable to two-dimensional echocardiography.

Adult↗
PubMedDate not supplied

Alternative tree-structured survival analysis based on variance of survival time.

Tree-structured survival analysis (TSSA) is a popular alternative to the Cox proportional hazards regression in medical research of survival data. Several methods for constructing a tree of different survival profiles have been developed, including TSSA based on log-rank statistics, martingale residuals, Lp Wasserstein metrics between Kaplan-Meier survival curves, and a method based on a weighted average of the within-node impurity of the death indicator and the within-node loss function of follow-up times. Lu and others used variance of restricted mean lifetimes as an index of degree of separation (DOS) to measure the efficiency in separations of survival profiles by a classification method. Like tree-based regression analysis that uses variance as a criterion for node partition and pruning, the variance of restricted mean lifetimes between different groups can be an alternative index to log-rank test statistics in construction of survival trees. In this article, the authors explore the use of DOS in TSSA. They propose an algorithm similar to the least square regression tree for survival analysis based on the variance of the restricted mean lifetimes. They apply the proposed method to prospective cohort data from the Study of Osteoporotic Fracture that motivated the research and then compare their classification rule to those rules based on the conventional TSSA mentioned above. A limited simulation study suggests that the proposed algorithm is a competitive alternative to the log-rank or martingale residual-based TSSA approaches.

Aged↗
PubMed1994

[Comparative analysis of certain nutritional parameters of fat in food rations of various population groups. II. Composition of fatty acids].

Daily food rations showed a high content of saturated fatty acids, especially in males and females employed in white collar work. The content of monounsaturated acids was lower, and the per cent of energy from these acids complied with the present nutritional suggestions. The per cent of energy from polyunsaturated acids was below these suggestions. The studied food rations contained high amounts of fatty acids with properties favouring hyper-cholesterolaemia and platelet aggregation, while those causing hypocholesterolemia (unsaturated acids) were present in insufficient amounts. This was noted particularly in the food rations of working people and retired workers. The variance analysis showed statistical. Significance of the differences between the mean values of the studied parameters of fats of various population groups.

Adult↗
PubMed1992

[The role of Doppler echocardiography in assessing left ventricular diastolic function. Case histories].

The aim of this study was to provide a further contribution to evaluate the alterations induced by age on a number of simple Doppler indexes of left ventricular diastolic function. A population of 48 healthy subjects aged between 15 and 78 years old was examined using pulsed Doppler analysis of the left ventricular refilling flow. Linear regression analysis revealed a significant inverse correlation between age and peak speed during rapid refilling (r = -0.80); between age and the ratio between peak speed during rapid refilling and peak during atrial systole (r = -0.92); between age and deceleration time of peak E wave speed, although on the contrary the peak speed of diastolic refilling flow during the atrial systole (r = 0.81) increased significantly with age. Variance analysis showed that indexes of left ventricular diastolic function and age continued on the contrary to be significant n the population as a whole and in both sexes. From these findings it is clear that in the different age groups (15-29, 30-49, 50-65, and over 65) the peak speed of rapid refilling flow was significantly lower in over-65-year-olds than in elderly, middle-aged and young subjects (55 +/- 0.8, 60 +/- 0.5, 65 +/- 0.7 and 75 +/- 0.6 respectively; p < 0.001). The ratio between the peak speed of rapid refilling and that during the atrial systole was lower in over-65-year-olds compared to elderly subjects, middle-aged subjects or the youngest age group (0.94 +/- 0.09, 1.05 +/- 0.13, 1.96 +/- 0.21 and 2.68 +/- 0.50 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[The fetal adrenal gland in risk pregnancy].

INTRODUCTION: The role of the adrenal gland in the metabolism of foetus and its role in maturation of foetal organs are the principal motives for paying more attention to this vital organ, which is still a great enigma for gynaecologists. The control of the gland is important in normal as well as in risk pregnancies. Of the entities that most often imperil the growth of foetus and adrenal glands are diabetes and hypertension in pregnancy. A consequence of the maternal diabetes may be macrosomy of foetus manifested by increase in foetal body mass and enlargement of organs sensitive to increased concentration of insulin in the foetal blood [6], i.e., the liver, fat tissue, lungs, adrenal glands, heart. Brown and Singer (1988) [2] established that adrenal glands of foetus are imperiled in pregnancies complicated by mother's hypertension. Their conclusion was derived from pathologic findings in foetuses from unsuccessful pregnancies of patients with hypertension. The glands were of reduced sizes. The way to perform precise measuring of glands, which are of dilapidated composition during post mortem examination, is not quite acceptable, since during the manipulation the size may, to some degree, be altered. By introduction of the ultrasound method in medical practice the problem of biometry has been overcome. Besides measuring, of great importance for the study of physiology of the gland is also the analysis of the foetal fluid and foetal blood. The first successful measuring of the adrenal gland of foetus by ultrasound was performed in mid 80s of the last century by Jeanty and Romero [3] via transabdominal path. The aim of our study is the comparison of foetal adrenal glands in normal and high-risk pregnancies. MATERIAL AND METHODS: During a prospective follow-up carried out at the Institute of Gynaecology and Obstetrics, Clinical Centre of Serbia, 213 patients, aged from 19 to 44 years were examined. Gestation periods were from the 11th to the 40th week. We divided the patients in 3 groups. The first group consisted of 131 patients with no pathologic changes and whose children were born alive. The second group was formed of 75 pregnant women in whom the course of pregnancy was impaired and disorders in the foetal. From these pregnancies the children were born alive. The third group was composed of 7 patients in whom abortion was indicated. The measured values of foetal adrenal glands diameter in the first group (131 patients), were used for making a nomogram of the glands growth. The measuring was performed with ultrasound apparatus "Toshiba 100 SSA". Transabdominal examination with a probe of 3.75 MHz and transvaginal examination with probes of 5 and 7 MHz were performed. Since the picture of the adrenal gland resembled an ellipse, on the basis of measured diameters and using the formula for circumference of this geometric figure [O = (d1 + d2) x pi/2], we obtained the desired value, which increased with advancement of pregnancy. Patients included in the study were with one-foetus pregnancy, whose last menstruation was precisely dated. Data are presented in a chart. For analysis of the obtained data, in addition to parameter methods, we also used the linear correlation and regression and one-factor analysis of variance. Data base analysis was made in the SPSS for DOS package. RESULTS: In making a nomogram of adrenal glands growth of a foetus old between 11 and 40 weeks, 131 of 213 patients were included, while the other foetuses were excluded as they belonged to high-risk pregnancies. Correlation of the growth of adrenal glands circumference and gestation period of pregnancy are also highly statistically important. The correlation coefficient of the straight line which represents this dependancy, is R = 0.8916, for the significance level of p < 0.01 (GRAPH 1). We observed how the course of pregnancy influenced the growth of foetal adrenal gland in normal pregnancies and in foetuses impaired by a pathological pregnancy course. By the method of one-way variance analysis, we obtained the value of the test, which was F = 2.79; p = 0.07. The graphical presentation of adrenal glands of a foetus in the appropriate week of gestation revealed that dimensions of glands in pregnancies impaired by diabetes were larger than those in normal gestations, and that they were at the top of border value of +2 SD or even over this limit. The statistically obtained value was F = 1.81; p > 0.05 (p = 0.06 and it was close to the border value for the significance level of p < 0.05); however, for glands of pregnancies complicated with hypertension the value was F = 1.61; p = 0.063 and the border value near -2 SD. Data are presented in a chart, regarding nomograms and adrenal glands of risk pregnancies. DISCUSSION: In 1993 Bronstein and colleagues [1] proved that the route of visualization of an adrenal gland was not only transabdominal. They succeeded in detecting the glands by transvaginal ultrasound examination in the 12th week. Jeanty and Romero [3] performed a successful transabdominal visualization in the 23rd week of gestation. By ultrasound prenatal examination we can determine the existence of hyperplasia of adrenal glands (Kelnar 1993) [5]. With ultrasound examination we can also diagnose tumours of the medulla, such as neuroblastoma (Jennings and colleagues 1993) [4]. In our study we reported on the visualization and growth of foetal adrenal glands in the period from the 11th to the 40th week of gestation. We presented the growth of foetal adrenal glands in normal gestations with the growth nomogram. The coefficient of correlation of adrenal glands circumference was R = 0.8916. The level of significance was p < 0.01. In conclusion, we can say that risk factors in pregnancy could impair the growth of adrenal glands. We have found that foetal adrenal glands in pregnancies impaired with maternal diabetes were hypertrophic, while those in pregnancies impaired with hypertension were almost at hypotrophic border. The nomograms of adrenal glands growth were of clinical importance, since they help us to control the state of a foetus in high-risk pregnancies. CONCLUSION: Improvement of the methods used in prenatal diagnosis will contribute to a timely detection of a diseased foetus, and will be the first step in its recovery. Regulating the pathological condition of the mother will surely contribute to decrease the risk of delivering children with an increased risk of morbidity.

Adrenal Glands↗
PubMed2005

Understanding adherence to official guidelines on statin prescribing in primary health care--a multi-level methodological approach.

OBJECTIVE: The aim was to investigate the role that municipalities and out-patient health care centres (HCCs) have in understanding adherence to official guidelines on statin prescribing. Our hypothesis was that after guideline publication, adherence to recommended statin prescription would increase and variance among HCCs and municipalities would decrease. Since multi-level regression analysis (MLRA) is a relatively new methodology in pharmacoepidemiology, we also aimed to explore the application of MLRA in our investigation. METHODS: We obtained data from the Swedish Corporation of Pharmacies record of sales regarding all initial prescriptions of statins issued between April and December 2003. We applied multi-level analysis on 34,514 individual prescriptions (level 1) nested within 226 HCCs (level 2), which in turn were nested within 33 municipalities (level 3). Temporal trends and gender differences were investigated by means of random slope analysis. Variance was expressed using median odds ratio (MOR) and interval odds ratio. RESULTS: HCCs appeared to be more relevant than municipalities for understanding the physicians' propensity to prescribe a recommended statin (MOR(HCC) = 1.96 and MOR(Municipality) = 1.41). Overall prevalence of adherence was very low (about 20%). After publication of the guidelines, prescription of recommended statins increased, and variance among HCCs decreased but only during the first 4 months of the observation period. CONCLUSION: The publication of official guidelines in the county of Scania exerted a positive influence on statin prescription but, at the end of the observation period, adherence was still low and practice variation high. These facts may reflect inefficient therapeutic traditions and suggest that more intensive interventions may be necessary to promote rational statin prescription.

Drug Prescriptions↗
PubMed1995

[Hair mercury levels in different occupational groups in a gold mining zone in the north of Colombia].

Hair mercury analysis was carried out on a sample of 219 people living in the main gold mining zone of Colombia, 27 inhabitante of Cartagena City being taken as control sample. For data analysis the sample was divided by occupation and the corresponding the hair mercury concentrations (mean +/- SD) were found to be 5.23 +/- 5.78, 2.83 +/- 3.27, 2.4 +/- 2.02 and 1.33 +/- 0.74 micrograms/g for fishermen, miners, people of various other activities and the control sample, respectively. According to variance analysis and the Newman Keuls test, there were significant differences (p < 0.01) between the mercury concentrations for fishermen and those for the other groups. No significant differences were found for hair mercury and sex, non was any correlation with age detected; however, a low positive correlation (R = 0.15, p < 0.01) with the frequency of the consumption of fish was noted. The main symptoms of mercury poinsoning observed in the persons exposed were headache, oral lesions, metalic taste, loss of memory, and irritability.

Adolescent↗
PubMed1983

Antibodies to nucleic acids in systemic lupus erythematosus and rheumatoid arthritis patients and their relatives.

Sera of systemic lupus erythematosus (SLE) patients contain antibodies to double-stranded and single-stranded DNA while antibodies found in rheumatoid arthritis sera are specific mainly to single-stranded DNA. Anti-RNA antibodies in the both cases are directed against double-stranded RNA and belong to the IgM class while anti-DNA antibodies are IgG. Genetic variance analysis based on family correlations suggests that the synthesis of antibodies to DNA is subject to different modes of gene regulations in systemic lupus erythematosus and rheumatoid arthritis patients. In the case of SLE, a high degree of genetic determination is demonstrated, due mainly to the X-chromosomal component of the general phenotypic variance. The failures in the immunoregulation system that are responsible for anti-RNA antibody production are rather similar in the two groups of patients and involve a combination of environmental and autosomal factors.

Adolescent↗
PubMed1999

The needs of patients with arthritis: the patient's perspective.

OBJECTIVE: To identify concerns and learning interests of patients with arthritis. METHODS: A questionnaire was developed, pilot tested, and then used to evaluate 197 patients with arthritis, including osteoarthritis (OA) (n = 41), rheumatoid arthritis (RA) (n = 57), back disease (n = 55), systemic lupus erythematosus (n = 27), and systemic sclerosis (SSc) (n = 17). Twenty concerns and 12 learning interests were rated. Questionnaires were also administered to assess physical disability (Health Assessment Questionnaire), psychological disability (Arthritis Impact Measurement Scales 2), and pain (visual analog scale). Participants addressed accessibility of health services, satisfaction with their physician, psychosocial needs, use of self-help groups, and behavioral strategies used to assist coping. Patients with RA, OA, and back disease, at both a community and a hospital center, were tested to assess whether concerns and learning interests differed based on site of treatment. Analytic methods included analysis of variance, factor analysis, and multiple linear regression. RESULTS: There were no differences in concerns or learning interests based on treatment site. Between diagnostic groups, patients with SSc were more interested in learning about self-help groups. The most frequently reported concern was worsening of the illness. The majority of respondents were interested in learning more about topics that were illness specific. The physician was chosen as the preferred source of information, and the preferred format was in writing. On factor analysis, the 20 concerns were reduced to 5 factors: psychological, coping, medication, social, and financial. Three factors were identified for learning interests: the illness, traditional health management topics, and nontraditional health management topics. Stepwise multiple linear regression revealed predictors for the 5 concern and 3 learning interest factors. The concerns were best predicted by self-reported disease severity, physical disability, and psychological distress, while learning interests were best predicted by self-reported disease severity, pain, and self-help group membership. CONCLUSION: Concerns and learning interests of persons with arthritis did not differ based on the center of treatment or the diagnosis, but can be predicted by the level of pain and simple measures of disability. Better understanding of the relationship between health status and patient-perceived needs will result in improved patient-centered care.

Activities of Daily Living↗
PubMed2004

High serum leptin levels subsequent to weight gain predict renewed weight loss in patients with anorexia nervosa.

It has repeatedly been shown that high serum leptin levels at target weight ensue from therapeutically induced weight gain in patients with anorexia nervosa (AN). It was hypothesized that elevated leptin levels may be an important factor underlying the difficulties of maintaining the target-weight in AN patients after re-feeding. The aim of this study was to examine if serum leptin levels at discharge from inpatient treatment predict renewed weight loss within 2 months after discharge and upon a 1 yr follow-up. Univariate variance analysis (ANOVA) revealed that 60% (cor. R2=0.60, P=0.002) of the variance in the BMI standard deviation score (BMI-SDS) 2 months after discharge was explained by the model consisting of the independent variables lg10 leptin levels at discharge (P=0.019) and at admission (P=0.069) and BMI-SDS at admission (P=0.002) and delta BMI between admission and discharge (P=0.047). Similarly, 60% (cor. R2=0.60, P=0.005) of the variance in BMI-SDS 1 yr after discharge was explained by lg10 leptin levels at discharge (P=0.046) and at admission (P=0.052) and BMI-SDS at admission (P=0.008) and 2 months after discharge (P=0.007) and delta BMI between admission and discharge (P=0.933). Patients with a poor outcome after 1 yr (n=9, ANCOVA, group: descriptive P=0.041), but not recovered patients (n=9, P=0.649), had lg10 leptin levels at discharge higher than those of controls when adjusted for BMI and % body fat at discharge. In conclusion, high serum leptin levels at discharge from inpatient treatment may indicate a risk for renewed weight loss and an unfavorable 1 yr outcome in AN.

Adolescent↗
PubMed1997

Risk factors for clinically diagnosed Alzheimer's disease: a case-control study of a Greek population.

Many efforts have been made to trace the causes of Alzheimer's disease (AD). There are, however, many points of controversy among reports from the same country as well as among reports from different countries. The current study is a case-control study to determine the risk factors in the development of AD in Greece. Sixty-five patients with AD and 69 age-matched controls were examined. All patients with AD fulfilled the DSM-IV criteria for AD and NINCDS-ADRDA criteria for probable AD. Demographic characteristics such as gender, current marital status, who he/she is living with, education, main place of residence in childhood, adulthood, and late life, occupational hazards, patient's medical history (history of diabetes mellitus and hypertension), life habits like alcohol consumption and smoking, and a history of head trauma, heart attack, stroke, parkinsonism, or depression were collected from the subject or from an informant. A family history of selected diseases (hypertension, diabetes mellitus, dementia, Parkinson's disease, Down's syndrome, stroke) was also elicited. Ages of father and mother at birth were also recorded. Chi-square test, Kruskal-Wallis analysis of variance, cluster analysis, and logistic regression analysis were used for statistical analysis. The results (chi-square test) showed a statistically significant difference between patients with dementia of the Alzheimer type and controls as far as marital status (p = .04), the subject's history of major depressive episode (p = .02), and family history of dementia (p = .002) were concerned. Logistic regression analysis results produced a complex model of family aggregation of dementia, with patients with a history of depression and family history of dementia having an up to seven times higher risk of developing AD. These findings, especially a family history of dementia, are consistent with most of the literature.

Aged↗
PubMed2004

[Accumulation and translocation of lead in soil-crop system of green food production].

In this paper, the accumulation and translocation of lead in soil-crop ecosystems were studied through fertilization with chemical fertilizer, manure and bio-fertilizer. The results showed that the soil total Pb content was decreased with soil depth. It was 11.14 and 9.37 mg x kg(-1) in 0-15 and 15-30 cm after harvest, respectively. Rice root absorbed lead from soil, and transferred it to stem-leaf and grain. The Pb content in rice plant was root>stem and leaf>grain, which was increased with rice growth. The grains of 606-14 and Liao 294 contained 0. 008 and 0.007 mg x kg(-1) of Pb, respectively, which is under the standard of green food. Variance analysis indicated that the grain yield of different varieties had a significant variance, but no significant variance was found among different treatments. It could be summarized that manure or bio-fertilizer could be the substitute of chemical fertilizer in producing rice.

Absorption↗
PubMedDate not supplied

Quantitative analysis of limonin in grapefruit juice using an enzyme-linked immunoassay: interlaboratory study.

Eleven laboratories participated in an interlaboratory study of an enzyme-linked immunoassay for limonin in grapefruit juice. Participating laboratories received training and practice samples until familiar with the procedure. Laboratories then received 8 sample pairs of grapefruit juice as blind duplicates. Samples were refrigerated and analyzed within 4 days of receipt. Results from 1 laboratory and 6 individual samples were excluded from the statistical analysis. Method performance was measured by the one-way component of variance analysis. Repeatability relative standard deviations (RSDr) ranged from 7.0 to 15.6%. Reproducibility relative standard deviations (RSDR) ranged from 12.9 to 29.4%.

Beverages↗
PubMedDate not supplied

Power perceptions of Black nursing faculty.

The purpose of this study was to determine the perceptions of Black nursing faculty members to the concept of power. This study sought to answer the question: How do Black nursing faculty members perceive power and how are they oriented toward power? The Cavanaugh Power Orientation Scale (1978) was used to survey a random sample of 100 Black nursing faculty members obtained from a national listing. The data were analyzed using descriptive methods of measurement, factor analysis, Pearson Correlation Coefficients and analysis of variance. An analysis of the data show that factors did not load of the same variables as had been shown in Cavanaugh's study. The presentation will discuss the descriptive data and the scores obtained on each of the six factors. It is important to understand the perceptions that Black nursing faculty members have about the concept of power because these are the ideas and behaviors which may be promulgated by the nursing student.

Adult↗