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PubMed1977

[The effect of vincamine on cerebral blood flow as a function of application rate (author's transl)].

The effect of infusions of 14,15-dihydro-14beta-hydroxy-(3alpha, 16alpha)-eburamenine-14-carbonic acid methylester (vincamine; Vincopront) on cerebral blood flow (CBF) was investigated by the xenon clearance method. In 12 patients receiving 30 mg vincamine within 35--40 min no significant changes in hemispheric or regional CBF were observed. 14 patients received 40 mg vincamine within 35--40 min: in this group hemispheric CBF was significantly increased (p less than 0.01) when compared to the spontaneous changes observed in a control group. The increase was particularly prominent in poorly supplied brain regions. This effect was proved statistically by regression analysis. In a patient with astrocytoma the tumor-hyperperfusion was diminished by vincamine while the flow to the surrounding brain improved. The results indicate the dependency of the vincamine effect on the rate of application and thereby on the plasma concentration of the drug.

Adult↗
PubMedDate not supplied

[Beta 2 microglobulin in the serum as a parameter for the evaluation of kidney function in pregnant patients with EPH gestosis].

The renal function of 27 pregnant women with EPH-gestosis were determined by measuring the level of proteinuria, the serum concentration of blood-urea-n (BUN), creatinin, beta 2-microglobulin and the creatinin clearance, in comparison with, 39 healthy pregnant women were examined. For statistics the regressions line with the week of gestation and spearman correlation between our parameters (proteinuria, BUN, creatinin, creatinin clearance and gestosis-index) were determined. The level of the proteinuria as well as the concentration of BUN and serum-creatinin are only limited useful to check the degree of a restriction of the renal function in EPH gestosis. Significant correlations were found between beta 2-microglobulin concentration and the serum creatinin concentration as well as the creatinin clearance, but not between beta 2-microglobulin and the gestosis index. Immunologic reactions in EPH-gestosis seem not to have a significant influence on beta 2-microglobulin concentration, but only the restriction of the degree of the glomerular filtration. Therefore beta 2-microglobulin is a useful parameter for renal function.

Adult↗
PubMed1984

[Absorption of colostral immunoglobulins and its interdependence].

Three main factors underlying the immunity state of newborn calves are evaluated. During the absorption of colostral immunoglobulins the immunoprotein profile of a newborn calf is influenced by the following factors (arranged according to importance): volume of the first colostrum taken in, time of the first drinking, and immunoglobulin concentration (IgG and IgM) in colostrum. When given 1.1 or 2.0 litres of colostrum of about the same quality (as to immunity), the calves of the compared groups had significantly different levels of total serum Ig measured 24 hours after birth: 10.7 and 18.6 U ZST (P less than 0.05) and 48 hours after birth: 11.7 and 19.7 U ZST (P less than 0.01). A significant difference in total serum proteins was observed only in the 48th hour post partum (54.4 and 63.6 g per litre; P less than 0.05). At the intake of 1.5 litres of colostrum within two and five hours after birth, with the same total intake of the sum of IgG and IgM in the groups, the calves exhibited, in the 24th hour, total serum Ig levels of 14.4 and 12.4 U ZST (P greater than 0.05) respectively, and 56.0 and 47.9 g per litre (P greater than 0.05) of total serum protein, respectively. With a different concentration of colostral IgG (122.0 or 77.0 g per litre) the statistically significant Ig absorption into blood was adequately different (17.2 and 10.0 U ZST, respectively, P less than 0.05). The differences in the concentration of total serum Ig and total proteins between the 24th and 48th hour after birth were only very small and statistically insignificant. Regression analysis proved a significant relation (P less than 0.01) between the level of total serum Ig 24 and 48 hours after birth and the total amount of IgG and IgM taken in with the first colostrum. The calves coming from primiparae had a lower immunity (P less than 0.01) in comparison with the calves of multiparae. A similar relation in the absorption of colostral Ig was observed when the spontaneously born calves were compared with those born by the Caesarean section (P less than 0.01).

Animals↗
PubMedDate not supplied

Contraceptive continuation among adolescents attending family planning clinics.

An attempt to find a reliable way to measure contraceptive continuation among teenagers was made in a study of 445 adolescents under age 18 who made an initial visit to one of nine federally funded family planning clinics in the Philadelphia area in 1980 and 1981. The participants were interviewed at their initial visit and at six and 15 months to collect information on background characteristics, pregnancy history and contraceptive use. A cross-check of the information on contraceptive use reported during the study showed that 38 percent of the respondents who reported that they had been continuous users during the 15 months supplied information at other points indicating that they had not always used contraceptives during that period. In an attempt to examine the effects of adolescent reporting errors on measures of contraceptive use, the investigators constructed three alternative measures of contraceptive continuation. The simplest measure assessed current use at 15 months. A second measure accepted only reports of continuous use at 15 months and ignored inconsistent data. The third measure corrected for inconsistent data. Applying these measures to the study population produced proportions of contraceptive continuation ranging from a low of 43 percent when the most stringent measure was used to a high of 82 percent for the current-use category. Whatever the measure used, much of the discontinuation appears to have occurred in the first three months after the initial visit to a family planning clinic.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1984

The postcoital test as a predictor of pregnancy among 355 infertile couples.

Late follicular phase postcoital tests in 355 infertile couples (selected to exclude severe defects in ovulation, seminal or tubal function) were scored for mucus characteristics and sperm motility. Cervical mucus characteristics were associated with postcoital sperm motility (P less than 0.001) but not with pregnancy. Postcoital sperm motility in cervical mucus was strongly associated with total motile sperm count per ejaculate (F = 5.38, P less than 0.001). Postcoital sperm motility was a weak predictor of pregnancy when more than five motile sperm were observed per high power microscopic field. When the log rank tests for postcoital sperm motility were repeated in groups with low (less than 10 million) and high (10 million or more) total motile sperm count per ejaculate, the association between postcoital sperm motility and pregnancy was not statistically significant. Regression analysis controlling for other potential predictors revealed no independent association between postcoital sperm motility and the later occurrence of pregnancy in this group of infertile couples.

Adult↗
PubMed1982

Biliary lipids, bile acids, and gallbladder function in the human female: effects of contraceptive steroids.

Individuals who take contraceptive steroids or estrogens are at increased risk of developing cholesterol gallstones. The mechanisms of the increased stone formation are incompletely understood. In this study we report biliary lipid composition and secretion, bile acid composition and kinetics, and gallbladder function in a group of healthy, nonobese women taking a contraceptive steroid preparation. A comparable group of healthy women served as controls. Bile-rich duodenal fluid was obtained after stimulation of gallbladder contraction; bile acid, phospholipid, and cholesterol concentrations were determined. Biliary lipid secretion rate was measured by the marker perfusion technique. Bile acid distribution was determined by gas-liquid chromatography. The pool size, FTR, and synthesis rate of each bile acid were measured by using CA and CDCA labeled with the stable isotope of carbon, 13C. In some of the subjects gallbladder storage and emptying were measured during the kinetic study, by real-time ultrasonography. Contraceptive steroid use was associated with a significant increase in biliary cholesterol saturation and in the lithogenic index of bile. The rate of cholesterol secretion in the contraceptive steroid group was 50% greater than in the control (p much less than 0.001) and the rate of bile acid secretion was reduced (p less than 0.02). The total bile acid pool size was significantly increased by contraceptive steroids. The major increase occurred in the CA pool (p less than 0.04). The daily rate of enterohepatic cycles of the bile acid pool was decreased by contraceptive steroids from 6.6 to 4.3 (p less than 0.01). The only effect of contraceptive steroids on gallbladder function was a slower emptying rate in response to intraduodenal amino acid infusion. No index of gallbladder function correlated significantly with any parameter of bile acid kinetics in this small group of subjects. The findings confirm the lithogenic effect of contraceptive steroids and indicate that its causes are an increase in cholesterol secretion and a decrease in bile acid secretion.

Bile↗
PubMed1981

[Influence of age on blood glucose levels: percentile reference intervals determined on ambulatory patients].

Data of routine chemical and hematological laboratory tests regarding outpatients were collected in four different hospitals of the provinces of Ferrara, Rovigo and Bologna. Data of about 1500 subjects per hospital were cumulated without preliminary selection of patients; sex, age and pregnancy status were also recorded. At the end of the collection, the second (and third) record of the same patient was discarded; only those referring to the first examination were retained. In this report we consider only the values of the blood sugar level which were obtained by enzymatic methods. Descriptive statistics and regression analysis were performed utilizing a CDC CYBER 70/76 computer. The means and the variances of the data collected at the four hospital laboratories were very similar (Tab 1). The interlaboratory analysis of variance was poorly significant. All frequency distributions were leptocurtic and skewed to the right (Fig. 1). The blood sugar level tend to increase with age (Tab. 2). This correlation is graphically depicted in a two-dimensional plot (Fig 2) in which the regression line and the 2, 5 and 97,5 percentile levels corrected for age were also reported. We think that this diagram may be more helpful to the clinicians interpreting laboratory results than the usual "normal values".

Adolescent↗
PubMed1978

Correlations between quality and pigment parameters in young Beaujolais red wines.

The commercial qualities of 15 young Beaujolais red wines from the 1974 and 1975 vintages were scored by experienced tasters in the following summers. Measurements were made of a wine colour and the separate contributions to it by the coloured anthocyanins and the polymeric pigments, b total anthocyanins (coloured plus non-coloured) and c total pigments, i.e. total anthocyanins plus total polymers (coloured and non-coloured). All the tasting and analytical data were subjected to regression analysis. Statistically significant correlations were found in both years: a. Between overall quality and the contents of total pigments, total anthocyanins, coloured anthocyanins and the tasters' mean colour scores; b. Flavour and the contents of total pigments and total anthocyanins. Thus the colour of the acidified wine (total pigment) was the most simple indication of flavour and quality in these young wines of the same variety and age. In other respects there were marked differences between the vintages. In 1974 additional significant correlations were found a between overall quality and wine colour, pH and non-coloured anthocyanins, b between flavour and colour scores and coloured anthocyanins, and c between aroma and total pigments, total anthocyanins, coloured and non-coloured anthocyanins and pH. In 1975, flavour correlated with non-coloured anthocyanins and pH. The results demonstrate the desirable effects of anthocyanins on quality.

Anthocyanins↗
PubMed1995

[Relative hypoparathyroidism associated with CAPD treatment using normo-calcemic (3.5mEq/1) dialysate: an approach from transperitoneal calcium balance].

We investigated factors affecting net transperitoneal calcium balance (Ca-BL) and the level of parathyroid hormone in relation to stepwise changes in serum calcium, by short PET (peritoneal equibrium test during 240 min: using 2000 ml of 2.5% dextrose dialysate containing 1.75 mmol/L Ca) in uremic patients undergoing stable CAPD. We calculated Ca-BL (mg/effluent/PET) of 244 effluents obtained from 90 patients receiving calcium carbonate as a phosphate binder without vitamin D supplementation. Their serum calcium level corrected with albumin (cSCa), alkaline phosphatase activity (ALP) and intact-PTH level was 9.7 +/- 0.9 mg/dl, 236 +/- 83 mIU/ml and 153.0 +/- 172.4 pg/ml, respectively. We proposed two statistic significant regression lines between Ca-BL and total drainage effluent volume (Ca-BL = 133X - 0.056: r = 0.981, P < 0.001), cSCa (Ca-BL = -12.9X + 123.6: r = 0.941, P < 0.01). Total drainage volume (TDV) and cSCa were two major factors affecting Ca-BL. A TDV level of 2430 ml/240 min-PET or more was required for positive Ca-BL in cases with 9.5-10.0 mg/dl of cSCa, using this linear regression analysis. A cSCa level of 9.6 mg/dl or more was also required for positive Ca-BL in cases with 2400-2600 ml/240min-PET. We also proposed a significant linear regression line between the intact-PTH level and cSCa (i-PTH = -90.5X + 1015.8, r = 0.973, P < 0.01). This line suggest that 200 pg/ml of intact PTH was obtained by 9.0 mg/dl or less of cSCa level in 90 CAPD uremic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Quality improvement: analysis and modeling based on survey results.

This paper describes the results of the survey conducted in the manufacturing, distribution, and service organizations regarding total quality management (TQM) implementation. These results proved that an effective TQM program should contain consistent training of all employees and managers in TQM issues, significant improvement in communication methods between departments implementing TQM, development of the standards to measure and control the cost of quality, and reliable information about the results of TQM implementation. Based on the survey results, the quantitative relationships between quality improvement characteristics and different internal factors are presented. Statistical models described in the paper revealed leading predictors of a successful TQM implementation.

Humans↗
PubMed1994

Varied forms of bias due to nondifferential error in measuring exposure.

Continuous exposure variables are frequently categorized in epidemiologic data analysis. It has recently been shown that such categorization may transform nondifferential error in measuring continuous exposure variables into differential exposure misclassification. This paper assesses the direction and magnitude of the resulting misclassification bias under a variety of practically relevant forms of nondifferential measurement error. The expected bias of measures of the exposure-disease association is toward the null in the case of purely random measurement error with a mean of zero. Systematic nondifferential over- or underestimation of the exposure may bias measures of the exposure-disease association either toward the null or away from the null, depending on the underlying distribution of exposure, the true exposure-disease relation, and the cutpoints employed for categorization. If exposure measurement error has both random and systematic components, the direction of the net bias is less predictable than with pure error of either type, but bias toward the null is increasingly likely as the random component grows larger. The results indicate the need for careful evaluation of potential effects of nondifferential exposure measurement error in epidemiologic studies in which categories are formed from continuous exposure variables.

Bias↗
PubMed1994

Prognostic value of thallium-201 per rectum scintigraphy in alcoholic cirrhosis.

METHODS: In a 4-yr survival study, the prognostic value of the inferior mesenteric shunt, as evaluated by 201Tl per rectum scintigraphy, was assessed in 170 alcoholic cirrhotic patients. The global severity of the hepatic disease was assessed by the Child score, and specific hepatocellular function was evaluated by the aminopyrine breath test. Using 201Tl scintigraphy, three groups were considered: group I, heart-liver activities ratio (H/L ratio) < or = 0.5, n = 55; group II, H/L between 0.5 and 0.85, n = 50; and group III, H/L > 0.85, n = 65. RESULTS: The 4-yr survival rates in the three groups were 76%, 36% and 18%, respectively. The log-rank test showed that the differences between the groups were statistically significant. Regression analysis using Cox's proportional-hazards model showed that the three parameters, Child score, aminopyrine breath test results and H/L ratio were significantly related to survival. CONCLUSION: The inferior mesenteric shunt per se has a prognostic value in alcoholic cirrhosis. Moreover, the H/L ratio provides additional information on survival after the Child score and the aminopyrine breath test results have been taken into account.

Administration, Rectal↗
PubMed1993

The analysis of case-control studies under validation subsampling.

In case-control studies, one often finds that covariates are missing or measured with error in the entire sample, whereas complete or exact covariate information is available only in a subsample. This paper discusses the analysis of case-control studies under a double-sampling scheme, where at the first stage covariates are measured with error or missing, and at the second stage are validated in a subsample. The method proposed combines the risk information from both samples by assuming that (1) the disease incidence model is logistic, (2) the partial or proxy information takes on finitely many values, and (3) the error is non-differential. The estimator is obtained by jointly fitting logistic models to the first and second stage data, a variance formula is presented. Parameters can be estimated by use of standard packages for dose-response data. Data from an ongoing case-control study on lung cancer serve as an example.

Aged↗
PubMed1993

Pharmacokinetics of minocycline and vancomycin in rabbits.

The pharmacokinetic disposition of minocycline and vancomycin was studied in New Zealand White rabbits before initiating an experimental staphylococcal endocarditis protocol. Minocycline was administered in a multiple-dose regimen of 3 mg/kg i.v. every 12 h, 3 mg/kg i.v. every 8 h, and 6 mg/kg i.v. every 8 h. Vancomycin was given in a similar fashion using regimens of 75 mg/kg i.v. every 12 h and 50 mg/kg i.v. every 8 h. Multiple serum samples were obtained after the fifth dose and drug concentrations were analyzed by microbiologic assay. The pharmacokinetic parameters for each of the drug regimens were calculated using a two-compartment model by nonlinear least-squares regression. No statistically significant differences were noted in the volume of distribution or the half-life of the individual dosing regimens for either agent. As a result of this study, it appears that a minocycline regimen of 6 mg/kg i.v. every 8 h and a vancomycin regimen of 50 mg/kg i.v. every 8 h are appropriate dosing schemes for a comparative study of these agents in rabbits.

Animals↗
PubMed1993

The effect of artificial caput on performance of vacuum extractors.

OBJECTIVE: To isolate and describe the effect of chignon formation (vacuum-induced caput) on the performance of six vacuum extractors. METHODS: Six vacuum extractors were examined in the laboratory: the 6-cm Malmstrom, Mityvac, M-Type, Silc, Silastic, and Tender-Touch. The devices were tested in two model systems that duplicated the fetal scalp with and without chignon. A fetal cephalic model mimicked the head without chignon. The second model used the hind quarters of anesthetized dogs. Chignon was formed by slowly increasing vacuum until the target vacuum was reached. At increments of vacuum, traction was applied in the axis of the cup and maximal tractive force (pop-off) was measured. RESULTS: A statistically unique regression line described each device. There was no significant difference in the regression lines for the Malmstrom and M-Type cups with or without chignon. At equal vacuum, there was a significant decrease (P < .05) in maximal tractive force with chignon formation in the bell-shaped cups. CONCLUSIONS: There is a demonstrable deterioration in the performance of bell-shaped cups with the formation of chignon. These data suggest that when using a bell-shaped extractor, efforts should be directed toward minimizing chignon formation by applying vacuum only with traction.

Animals↗