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PubMedDate not supplied

Predicting postoperative arterial pressure in renovascular hypertensive patients.

The authors have developed a method for forecasting the degree of the hypotensive effect of surgery for renovascular hypertension. Fifteen digital parameters were determined in 36 patients with unilateral lesions of the renal arteries by the following methods of preoperative examination: the establishment of the duration of hypertension, radio-isotope renography, determination of renin activity in the peripheral and renovascular (venous) blood, rheonephrography. The obtained set of characteristics was used for the prediction of postoperative arterial pressure values by means of one of the methods of mathematical statistics, the regression analysis in an "SM-4" electronic computer according to a specially created multivariate regression program in the "Fortran-4" language. The high accuracy of predicting the arterial pressure by this method was confirmed by clinical trials. Forecasting postoperative arterial pressure by this method allows us to substantiate with a high degree of fidelity the advisability of reconstructive surgery and opens up realistic prospects for improving its results.

Adult↗
PubMed1989

Nutritional status, age and survival: the muscle mass hypothesis.

The relevance of nutritional indices derived from comparison with growth standards to assess the risk of dying was evaluated in a 2-year prospective study in rural Senegal. An average of 3151 children aged 6-59 months were measured twice a year and followed up during the intervening 6-month periods. Children who survived and those who died during follow-up were found to differ more by anthropometric measures directly related to absolute muscle mass (viz. weight, height or arm circumference) than by nutritional indices obtained from comparison with growth standards (weight-for-age, weight-for-height and height-for-age). The findings could not be explained by a confounding effect of age. This brings into question the current approach used to identify high-risk children.

Age Factors↗
PubMed1989

Factors influencing breastfeeding behaviour.

The influence of nine socio-demographic factors (family size; child spacing; socio-economic status; mother's employment, education, age and weight; birth weight; and father's education) on the duration of exclusive breastfeeding was studied in a group of urban mothers. Only a small fraction (15%) of the wide variability in breastfeeding behaviour could be related to these factors. Educated mothers alone started artificial feeds significantly earlier (p less than 0.05). Our findings suggest that the decision to breastfeed is largely an individual one and not related in any simple way to the easily measurable characteristics.

Breast Feeding↗
PubMed1989

[Inter-hospital comparison of perinatal intensive care in academic hospitals].

Data on infants born in 1983 with a gestational age of less than 32 weeks and a birth weight under 1500 g were collected in the Project on Preterm and Small for gestational age infants (POPS). It was found that the mortality odds of these neonates were lowest when they were born in one of the eight departments of obstetrics in university hospitals and subsequently admitted to the neonatal intensive care units (PICUs). Comparison of the eight PICUs revealed considerable differences in crude mortality but this was due to differences between the groups of patients. After correction for this variability by means of a multivariate analysis technique (logistic regression), no statistically significant differences in mortality were found. The actual mortality rates in all PICUs virtually equalled the mortality to be expected on the basis of the abnormalities in the patient groups in question.

Academic Medical Centers↗
PubMed1989

[A study on the effect of cold applications using a sponge bath in healthy adults].

This study was a quasi-experimental research study to test the characteristics of temperature regulation according to sponge bath methods of cold application. Thirteen volunteers were selected from among nursing college students according to an established criteria using a purposive sampling technique. Four different cold application methods were used: (1) tepid water sponge bath at 28 degrees C, (2) 20% alcohol sponge bath at 28 degrees C, (3) 40% alcohol sponge bath at 28 degrees C and (4) tepid water sponge bath at 28 degrees C plus an ice bag to the head. Changes in rectal temperature, mean skin temperature, mean body temperature, heat content change and thermal discomfort during the cold application were measured at 5 minute intervals over a 120 minute period. The data collection period was from Dec. 20, 1988 to Feb. 3, 1989. The data were analyzed using descriptive statistics, simple regression, ANOVA, Duncan's multiple range test and Pearson correlation coefficient using the SPSS-X Program. The results of the study are summarized as follows. Five general hypothesis were tested. Hypothesis 1 that "Change in heat content will be decreased for each cold application method according to the cold application time" was rejected. (tepid water sponge bath: after 10 minutes of cold application, 20% alcohol sponge bath: after 25 minutes of cold application: 40% alcohol sponge bath: after 45 minutes of cold application, tepid water sponge bath plus an ice bag to the head: after 80 minutes of cold application). Hypothesis 2 that "Thermal discomfort will be changed for each cold application method according to the cold application time" was rejected after 5 minutes of cold application. Hypothesis 3 that "Change in heat content will differ among the cold application methods" was accepted except 0-5, 0-10, 0-65, 0-105 and 0-120 minute. This difference showed significance only between sponge bath methods and tepid water sponge bath plus an ice bag to the head. Hypothesis 4 that "Thermal discomfort will differ among the cold application methods" was accepted at 15, 20, 35, 45, 75, 80, 90, 95, 100, 105, 110, 115 and 120 minute of cold application time. This difference showed significance only between sponge bath methods and tepid water sponge bath plus an ice bag to the head. Hypothesis 5 that "The higher the change in heat content, the higher the thermal discomfort during the cold application time" was accepted for between 10-60 and 75 minute of cold application.(ABSTRACT TRUNCATED AT 400 WORDS)

Acclimatization↗
PubMed1989

Proportionality of 60-Hz electric field bioeffect severity to average induced transmembrane potential magnitude in a root model system.

The postulate that electric field-induced bioeffects in the root model system are related to the induction of 60-Hz transmembrane potentials (Vim) was quantitatively tested. Root segment growth rate data and the calculated mean 60-Hz Vim which would arise in the cortical cells of a segment under specified exposure conditions were subjected to regression analysis. Statistically significant correlations between segmental growth rate and segmental-average Vim were obtained using data analyzed (1) within species at a constant applied field strength, (2) within species and pooled across field exposures, and (3) pooled across both species and exposures. In C. sativus roots, segmental growth is inhibited when segmental-average Vim attain a value of 3.4-3.6 mV. In C. maxima roots, growth inhibition occurs when Vim attain or exceed 2.3-2.7 mV. Segmental growth cessation is predicted to occur when segmental-average Vim exceed 7-9 mV.

Cell Physiological Phenomena↗
PubMed1988

Effects of medical history factors on symptom severity in women meeting criteria for premenstrual syndrome.

Medical history variables were examined to identify their effects on the severity of premenstrual syndrome (PMS) in women seeking medical treatment. Symptoms were monitored daily for two untreated cycles and two placebo-treated cycles to establish the diagnosis of PMS. Data from 60 women who reported moderate to severe premenstrual mood changes and met criteria for PMS were analyzed statistically. Step regression analysis showed that 34% of the variance in symptom severity was explained by four variables: PMS in the patient's mother, low level of exercise, younger age, and more children. These significant relationships with severity of PMS have not previously been identified and suggest a role of familial and daily stress factors in this complex syndrome.

Adult↗
PubMedDate not supplied

The demand for family planning: a new approach.

A new "supply-demand" measure of family planning demand is compared with others commonly used to target prospective family planning clients. In analyses of data from six cross-sectional surveys the new measure consistently explains past contraceptive use better than the others. Time series analysis for two countries yields similar results. Family planning program officials may wish to consider exploring the use of this measure to target prospective clients.

Adult↗
PubMed1988

Concentration and distribution pattern of selected micronutrients in preterm and term milk from urban Brazilian mothers during early lactation.

The purpose of this study was to assess the concentration and binding pattern of zinc, iron, folate and vitamin B12 in milk of Brazilian women of low socioeconomic status giving birth at term or preterm, during early lactation. Protein, fat, total solids and ash concentrations were also determined. Protein and zinc concentrations decreased significantly as lactation proceeded whereas milk fat and folate increased with the lactation period. Total solids, ash, iron and vitamin B12 remained unchanged. Zinc was present mainly in the whey fraction while less than half of the total iron was present in this fraction, with no significant change due to stage of lactation. Unsaturated folate and vitamin B12 binding capacities and percentage of saturation of the folate binding protein increased with the stage of lactation. The vitamin B12 binding protein was highly unsaturated in all samples. There was no significant difference between term and preterm samples in the parameters investigated. Correlation analysis between milk components indicated significant relationships between total solids and fat, total zinc and whey zinc, folate and total folate binding capacity, unsaturated and total folate binding capacity, and unsaturated and total B12 binding capacity. In general, the nutrient concentrations found in this study are in good agreement with published data on milk composition of women from developed countries, with the possible exceptions of folate, which was lower, and iron, which was higher. The correlation of folate concentration with its binding protein found in this work supports the hypothesis of a regulatory role for folate levels in milk exerted by the folate binding protein in the mammary gland.

Adolescent↗
PubMed1987

Mercury concentrations in the human brain and kidneys in relation to exposure from dental amalgam fillings.

Samples from the central nervous system (occipital lobe cortex, cerebellar cortex and ganglia semilunare) and kidney cortex were collected from autopsies and analysed for total mercury content using neutron activation analyses. Results from 34 individuals showed a statistically significant regression between the number of tooth surfaces containing amalgam and concentration of mercury in the occipital lobe cortex (mean 10.9, range 2.4-28.7 ng Hg/g wet weight). The regression equation y = 7.2 + 0.24x has a 95% confidence interval for the regression coefficient of 0.11-0.37. In 9 cases with suspected alcohol abuse mercury levels in the occipital lobe were, in most cases, somewhat lower than expected based on the regression line. The observations may be explained by an inhibition of oxidation of mercury vapour. The regression between amalgams and mercury levels remained after exclusion of these cases. The kidney cortex from 7 amalgam carriers (mean 433, range 48-810 ng Hg/g wet weight) showed on average a significantly higher mercury level than those of 5 amalgam-free individuals (mean 49, range 21-105 ng Hg/g wet weight). In 6 cases analysis of both inorganic and total mercury was carried out. A high proportion (mean 77% SD 17%) of inorganic mercury was found. It is concluded that the cause of the association between amalgam load and accumulation of mercury in tissues is the release of mercury vapour from amalgam fillings.

Adolescent↗
PubMed1986

Risk factors for acquiring pneumococcal infections.

To identify risk factors for developing pneumococcal infections, we carried out a case-controlled study on a retrospectively constituted cohort of 3074 clinic patients in a presumed high-risk population. Culture-proved pneumococcal infections were identified in 63 men over a period of 5.5 years, yielding an estimated incidence of 6.3 cases per 1000 person-years. By comparing these patients with 130 uninfected control patients, the relative risk of pneumococcal infections related to various exposures was calculated by logistic regression analysis. Statistically significant independent risk factors (and their relative risks) were as follows: dementia (5.82), seizure disorders (4.38), current cigarette smoking (4.00), congestive heart failure (3.83), cerebrovascular disease (3.82), institutionalization (3.13), and chronic obstructive pulmonary disease (2.38). Risk was increased with age and previous hospitalizations, and, to a nonsignificant degree, by hotel residence (3.93), lung cancer (2.24), previous smoking (2.14), corticosteroid use (1.81), and alcoholism (1.35); but not by diabetes mellitus (0.99), nonlung malignancies (0.93), nonwhite race (0.89), or ischemic heart disease (0.58).

Aged↗
PubMed1986

[Cholesterol, phospholipid and apoB composition of LDL: comparison of precipitation and ultracentrifugation methods].

Cholesterol, phospholipid and apoB levels were determined in LDL precipitated by amphiphatic polymers (Biomérieux kit, Marcy-l'Etoile, France). Intra-assay and inter-assay analysis performed on 4 serum pools were satisfactory. For 113 sera (triglyceride level less than 4.5 mmol/l, absence of VLDL-remnants), the 3 variables were well correlated with those of centrifuged LDL (0.93 less than r less than 0.98); however, LDL-cholesterol values were significantly higher (p less than 0.001), and those of LDL-phospholipids (p less than 0.001) and LDL-apoB (p less than 0.005) significantly lower. The correlations between the 3 constituents studied gave statistically different regression coefficients for the two methods. It is concluded that these precipitated lipoproteins do not seem to correspond to LDL but to "LDL markers".

Apolipoproteins B↗
PubMed1985

[Anxiety as a state and anxiety as a personality trait in patients with diseases of the abdominal organs before and following operation].

63 persons were examined by means of psychologic methods: 32 patients with surgical diseases of the abdomen and 30 healthy people. The results show that an increase of the level of anxiety as an emotional state is mostly caused by the somatic disease and situations connected with it. After operation, a statistically relevant regression of the results will occur in this scale. In the preoperative period the whole population of patients is characterized by an emotional lack of balance, viz. tendency to autoaggression and neurotic anxiety. In the post-operative period there was no decrease in all factors constituting the hypothetical sources of anxiety. In studies of surgical patients it is important to differentiate anxiety as a state and anxiety as a personal feature.

Abdomen↗