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PubMedDate not supplied

[Control over the bacteriological quality of preparations for TPN by the sequential sampling technic].

A sequential microbiological control was carried out, using a total filtration method, on a sample selected at random from among those prepared on a daily basis and kept at room temperature for twenty-four hours, in order to determine any possible contamination by fungi, bacteria or yeasts. The results obtained were submitted to accumulated sum statistical sampling, the adjustment for which followed a binomial distribution model. For alpha = 0.05, levels of 0.04 and 0.12 respectively were fixed for acceptable quality (NCA) and for rejection (NCR). It was shown that the regulations on work in the unit for the preparation of NPT mixtures is satisfactory, as the latest results obtained are within the NCA established and, as a value, it is sufficiently exacting. The imperative need for routine microbiological control is also made clear, in order to maintain and improve the standard of quality in the section.

Bacteria↗
PubMed2004

Search for poliovirus carriers among people with primary immune deficiency diseases in the United States, Mexico, Brazil, and the United Kingdom.

OBJECTIVE: To estimate the rate of long-term poliovirus excretors in people known to have B-cell immune deficiency disorders. METHODS: An active search for chronic excretors was conducted among 306 persons known to have immunoglobulin G (IgG) deficiency in the United States, Mexico, Brazil, and the United Kingdom, and 40 people with IgA deficiency in the United States. Written informed consent or assent was obtained from the participants or their legal guardians, and the studies were formally approved. Stool samples were collected from participants and cultured for polioviruses. Calculation of the confidence interval for the proportion of participants with persistent poliovirus excretion was based on the binomial distribution. FINDINGS: No individuals with long-term excretion of polioviruses were identified. Most participants had received oral poliovirus vaccine (OPV) and almost all had been exposed to household contacts who had received OPV. Polioviruses of recent vaccine origin were transiently found in four individuals in Mexico and Brazil, where OPV is recommended for all children. CONCLUSION: Although chronic poliovirus excretion can occur in immunodeficient persons, it appears to be rare.

Adolescent↗
PubMed1992

A modified transfusion program for prevention of stroke in sickle cell disease.

Regular red blood cell transfusions reduce the rate of recurrent cerebral infarction in sickle cell disease but lead to accumulation of excessive iron. We studied the effect on the prevention of recurrent stroke and the volume of blood transfused of a modified transfusion program in which the pretransfusion percentage of hemoglobin S (HbS) was maintained at 50%, rather than the conventional 30%. Fifteen patients with sickle cell disease and cerebral infarction who had been free of recurrent stroke for at least 4 years during which the pretransfusion HbS was maintained below 30% were assigned to a transfusion program in which the HbS was allowed to increase to 50%. Transfusion regimens included simple transfusion and manual and automated partial exchange transfusion. The duration of follow-up was 14 to 130 months with a median duration of 84 months. None of the 15 patients had a recurrent cerebral infarction during 1,023 patient-months in which the target pretransfusion HbS was 50%. Analysis of this finding, using a binomial distribution, indicates that there is less than a 5% chance that the risk per patient of recurrent stroke in the first year of the modified transfusion program is greater than 18%. One 23-year-old patient had a fatal intraventricular hemorrhage when the HbS was 30% and a 21-year-old patient had a fatal subarachnoid hemorrhage in the 40th week of pregnancy when the HbS was 29%. Blood requirements with simple transfusions decreased by 17% to 48% (mean 31%) when the target pretransfusion HbS level was increased from 30% to 50% (P less than .001). Manual or automated partial exchange transfusions and a target HbS level of 50% in eight patients reduced blood requirements by 33% to 99% (mean 67%) in comparison with simple transfusion and a target HbS level of 30% (P less than .001). This study offers evidence that a target pretransfusion HbS level of 50% affords a continuing high rate of protection against recurrent cerebral infarction in sickle cell disease after 4 years of a conventional transfusion program. Increasing the target HbS level from 30% to 50% provides a major reduction in blood requirements and lowers the rate of iron accumulation.

Adolescent↗
PubMed2004

A simulation model for small-area cancer incidence rates.

OBJECTIVES: Cancer epidemiologists are often asked by members of the interested public about possible associations between suspected carcinogens and apparently increased small-area cancer incidence rates. Frequently, no systematic incidence differences can be demonstrated. Nevertheless, it is necessary to address public concerns about suspected cancer clusters. To facilitate explanations about the large random variation of small-area tumor incidence, we implemented a software simulation tool in R. METHODS: Under the assumption of no cancer causes other than chance, the tool simulates a small village population with an average number of five inhabitants per house and allows graphical visualisation of ten streets with 100 houses. Published age-specific incidence and mortality data are used for event sampling based on the binomial distribution. Program parameters include sample size, age distribution, cancer incidence, and mortality rates. RESULTS: On average, 22 percent (2.2/10) of all houses per street have been inhabited by at least one cancer patient during the last five years in our simulated small village. A situation where all (10) houses in a street have been inhabited by at least one cancer patient during the last five years appears to be very rare (less than one in a million streets). CONCLUSIONS: Our software tool can be used effectively for numerical and graphical visualisation of small-area tumour incidence and prevalence rates due to chance alone. The explanation of basic epidemiological concepts to members of the public can help to increase public motivation and support for population-based cancer registration. Our simulation tool can be used to support this goal.

Adolescent↗
PubMed1997

[Tailed normal chromatographic peak expressed by plate model].

An equation for describing tailed normal chromatographic peak is derived based on the plate model. In terms of the de Moivre-Laplace theorem, which states that a binomial distribution can be approximated by the Gaussian distribution for large sample size, it is suggested that the concentration distribution along the distance downstream from the inlet of chromatographic column conforms to the Gaussian distribution function, but the concentration distribution with elution volume (or elution time) does not. The equation developed here, which is similar to the Gaussian distribution function, indicates that the normal chromatographic elution curve should be a tailing one. It is also shown that the symmetric Gaussian elution curve is an approximate solution of the plate model and can be obtained by the approximation of the equation here. The equation is proved to be congruent to the results of the diffusion model. Thus, the plate model and diffusion model are equivalent to each other in describing chromatographic process although different mechanism is based on.

English Abstract↗
PubMed2005

[Spatial pattern relationships between emerald ash borer larvae and their natural enemies].

The investigation on the spatial patterns of emerald ash borer (EAB) larvae, parasitoid Spathius agrili, and EAB-preying woodpecker pecks in ash forests showed that in horizontal direction, EAB larvae, parasitoid S. agrili and woodpecker pecks were in negative binomial distribution, while in vertical direction, EAB larvae were distributed on ash trunks from above ground to 3.37 m in height, with a peak around the 1.50 m. Their natural enemies also favored this range.

Animals↗
PubMed2006

Estimation of bias between 2 analytical methods at clinically important ranges.

An approach for estimating bias between 2 analytical methods at different clinical ranges is introduced in this article. The approach models replicated data obtained from the reference and the test method in terms of repeatability and trueness bias. The latter can be partitioned into constant and proportional bias. The approach is based on maximum likelihood estimation and can accommodate normal as well as Poisson and binomial distributions that apply to hematology applications and/or other laboratory methods that count particles per unit of volume and/or time. A full spectrum of statistical inference in the form of confidence intervals for each estimate as well as any statistical hypothesis testing is provided. At the same time these estimates can be practically interpreted and related to any clinical important range or decision point. We recommend this approach as an alternative to the National Committee for Clinical Laboratory Standards (NCCLS) EP9-A2 approach in cases where the application of the NCCLS standard is not appropriate.

Bias↗
PubMedDate not supplied

[Neuropathic pain in Fabry's disease: heterogeneous remission in three years of enzyme replacement therapy].

INTRODUCTION: Fabry's disease is associated with acute neuropathic pain (NP). When six males with classic Fabry's disease ended three years of enzyme replacement therapy (ERT), studies were conducted to analyse the progression of the NP. PATIENTS AND METHODS: All of them received 1 mg/kg of agalsidase beta every 14 days. NP in hands and feet was evaluated at 0, 6, 12, 24 and 36 months, two modalities being considered: a) very intense pain or Fabry crises (FC), which forced the patient to rest, take analgesics and apply cold locally; b) acroparesthesias (AP), lower intensity itching, tingling and burning sensations that did not prevent them from continuing with their activities of daily living. The intensity of the FC (IFC) and the AP (IAP) were recorded using the Visual Analogue Scale, and the frequency with which both (FrFC and FrAP, respectively) appeared was measured in days. The one-tailed Wilcoxon test, binomial distribution and bootstrap method were used to carry out the analysis. RESULTS: After six months of ERT the IFC, IAP and FrCF remained the same, although the FrAP had become worse. As shown by the NP indexes that relate IFC/FrFC and IAP/FrAP, progress was therefore favourable. At one year, IFC continued, but FrFC and IAP were lower. At two years, the four NP measurements improved in five patients, although the FC and AP indexes did not vary in one patient. At three years, all the NP variables improved in the six patients. The slope representing NP as a function of time in all the bootstrap analyses was found to be p < 0.001. CONCLUSIONS: NP responded in a favourable, significant and heterogeneous manner and therefore justifies the early indication of ERT.

Adult↗
PubMed2006

Why does depression develop in complicated osteoporosis?

PATIENTS AND METHODS: In a prospective study we observed which female patients developed depression following an acute and painful vertebral fracture. For the statistical evaluation of questionnaires we chose randomly 32 patients with depression (out of 33 patients) aged 51-73, and 32 patients without depression (out of 44 patients) aged 52-70. THE AIM OF THE STUDY: To verify the hypothesis that the patients with more traumatic experience in the anamnesis (Questionnaire No. 1) are more depression prone following the osteoporotic vertebrae fractures and their character features are typical for subjects with higher emotional vulnerability (Questionnaire No. 2). STATISTICAL ANALYSIS: 1. Questionnaires 1 and 2 were evaluated by two statistical methods: a) automatization of mathematical and statistical estimates and tests based on binomial distribution; b) ADALINE Programme. 2. Assessment of relative risk for developing depression. RESULTS AND CONCLUSION: We recommend to use questionnaires No. 1 and 2 in female patients with acute painful vertebrae fractures to select patients with the risk of depression development. These patients should be followed more frequently as outpatients and in case of first clinical symptoms of depression should be recommended for special psychiatric care. Early therapy of depression enables to accelerate the mobilisation, rehabilitation and resocialisation of patients, to improve the quality of their lives and to reduce the costs of analgetic treatment of pain, sedatives and rehabilitation (Tab. 10, Fig. 2, Ref. 17).

Aged↗
PubMed1991

Low prevalence of delta hepatitis virus infection among blacks in Natal.

The prevalence of delta hepatitis virus (DHV) infection among hepatitis B surface antigen (HBsAg)-positive black subjects in Natal was determined. A total of 172 subjects was tested for the presence of antibodies to DHV; all were HBsAg-positive. They comprised three groups: 51 urban children identified in a community-based seroprevalence survey, 81 subjects identified during a family study, and 40 institutionalised children. None of the 172 subjects was positive for antibodies to DHV. Based on calculations using a binomial distribution of infection, there was a 95% probability that the prevalence of DHV infection was below 30/100,000 HBsAg-positive persons. While DHV infection was found to be rare among blacks in Natal, the risk of delta hepatitis becoming widespread is ever-present, since the high incidence of hepatitis B virus infection in black children provides ample opportunity for the concomitant spread of DHV.

Black or African American↗
PubMed1990

[A quantum analysis of the long-term posttetanic changes in the minimal postsynaptic potentials in surviving hippocampal slices].

Excitatory postsynaptic potentials (EPSPs) were recorded in guinea pig hippocampal slices (area CA1) from 13 neurons after single or double-pulse stimulation of stratum radiatum (the Schaffer collaterals) and stratum oriens. Amplitudes of 23 EPSPs (9 neurons, 12 pathways) grew 5 to 55 min after 10 tetanic stimulations of the Schaffer collaterals. This increase has been considered as a long-term potentiation (LTP). A statistical analysis was carried out by four methods of the quantal hypothesis based on the binomial distribution. It revealed an increase in the mean quantal content (m) during LTP. An increase in the quantal size was also observed in the majority of the cases but it showed only a weak correlation with the LTP magnitude and for some methods it was statistically significant only for the periods later than 15 min after tetanic stimulation. A well expressed increase in m demonstrated by various methods corresponds to data of the previous in vivo studies and favours the presynaptic location of mechanisms of the LTP maintenance.

Animals↗
PubMedDate not supplied

False-positive and false-negative proficiency test results in cytology.

Proficiency tests in cytology classify a certain proportion of cytologists inaccurately. Some competent cytologists fail during the testing procedure ("false-negative proficiency test" or "type I error") while some individuals who should fail do pass the test ("false-positive proficiency test" or "type II error"). In other words, success or failure during proficiency testing may be the consequence of statistical chance. Calculations based on the binomial distribution are presented to show the seriousness of this problem. The analysis demonstrated that increasing the number of slides in the test sets does not necessarily improve the accuracy of the test. For instance, on the 90% ("borderline competent") level, raising the number of slides in one test set from 10 to 20 reduced the accuracy of the test by 6%.

Cell Biology↗
PubMed1990

Incidence of hepatitis B exposure among USAF dental laboratory technicians.

The purpose of this study was to survey, serologically, the exposure history of USAF dental laboratory technicians to hepatitis B virus (HBV), and to compare the incidence to that found in the general military population. Blood samples from 145 technicians, with an average age of 26.9 (S.D. = 6.9) in four locations in the USA and Europe, were tested for the presence of HBV core antibody using a standard enzyme immunoassay (EIA) procedure. These results were compared against 397 military members in non-medical fields of equivalent age and rank. The binomially distributed data was converted to a z distribution and a statistically significant difference was found in a comparison of the probability of detecting anti-HBc in each population (P = 0.034) where the incidence among the technicians was 2.7% and the military population 0.76%. Use of a "barrier system" in the laboratory, and vaccinations, could prevent any increase in this incidence from an occupational source.

Adult↗
PubMedDate not supplied

Evaluation of a new cutaneous topical anesthesia preparation.

Topical anesthetic agents are usually not effective on intact skin because of poor penetration. EMLA is a new topical anesthetic formulation consisting of a eutectic mixture of the local anesthetics lidocaine 5% and prilocaine 5%. We evaluated the ability of this preparation to prevent or ameliorate the pain associated with the percutaneous placement of large IV catheters. Under double-blind randomized conditions, either EMLA or placebo was applied to the dorsum of both hands and an occlusive bandage then placed over each application site. The creams were placed 30, 45 or 60 minutes prior to IV cannulation. A 16-gauge catheter was inserted through each application area. Patients were asked to evaluate the relative degree of pain at each venous puncture site. The EMLA site was preferred when the formulation was applied for 45 to 60 minutes prior to cannula placement (p less than 0.01, confidence limits for the binomial distribution). Cusum analysis confirmed this minimal effective application time. The results indicate that EMLA is an effective cutaneous anesthetic formulation when applied with an occlusive bandage for a minimal time period of 45 minutes.

Anesthetics, Local↗
PubMed1989

[Random sample planning in morphometry].

This report tries to explain principles and presuppositions of planning sample sizes. The aim is estimation of the optimal, that means minimally necessary sample size, justifying an investigation ethically and economically. The problems are complicated because of the necessity of nested sampling or samples within samples. We describe the most important presuppositions using an example of mean value estimation. These are: establishing of demands for exactness, of error probability, and knowledge of variance of the parameters. It is explained in detail by means of binomially distributed variables as we find them in the point counting method.

Humans↗
PubMed1989

The ecology of Crepidostomum species (Allocreadiidae: Digenea) in the salmonoids of Lake Yli-Kitka in northeastern Finland.

Crepidostomum spp. were studied from 417 whitefish (Coregonus acronius Rapp, 1854), 220 vendace (Coregonus albula L.) and 38 brown trout (Salmo trutta m. lacustris (L.)) from Lake Yli-Kitka in northeastern Finland during 1980-1983.12.7% of the whitefish were infected with Crepidostomum with a mean intensity of 4.6 worms per infected fish. The species involvedare C. farionis (Müller, 1784) and Crepidostomum wikgreni Gibson et Valtonen, 1988, which differed from C. farionis in the number and size of the eggs. Both types were encountered in the gall-bladder and intestine, but were unable to be distinguished as immature stages. 21% of the brown trout harboured C. farionis in the intestine with a mean number of 1.5 worms per infected fish. Two C. farionis specimens occurred also in the intestine of one vendace. Whitefish smaller than 150 mm did not harbour Crepidostomum specimens, but in bigger fish the prevalence and the mean intensity of infection increased to a certain limit as the fish got larger. The prevalence of Crepidostomum infection also clearly increased during the three seasons in the three size-groups studied. The seasonal pattern of Crepidostomum in whitefish of the size greater than or equal to 150 mm was variable in that the lowest values, both in the prevalence and mean intensity of infection, occurred between September and December in 1980 and between April and August in 1982. Reinvasion was found throughout the year, although the main recruitment occurred during autumn and early winter. Eggs matured between late spring and early autumn. The smallest worms occurred mainly in the gall-bladder, and most of the gravid specimens were located in the intestine. Both the variance-to-mean ratio and the low values of the parameter k of the fitted negative binomial distribution reveal the Crepidostomum specimens are overdispersed in the whitefish of Lake Yli-Kitka.

Animals↗
PubMed1989

[Morphologic and quantum characteristics of sensomotor neuron synapses in isolated rat spinal cord].

The structural-functional relationships of sensorimotor connections were studied in isolated lumbar cord segments of 7-14 day-old rats. Individual motoneurons were found to have synaptic contacts only with a single collateral of the afferent fibre. The number of contacting boutons gained 10. The n parameter of the binomial model was established to reflect the number of contacts at the sensorimotor connection. The analysis of sensorimotor EPSPs by convolution with two binomial distributions has shown that sites of the transmitter release were different in their probability (efficiency) of response to nerve impulse.

Animals↗
PubMed1985

[Family aggregation of hepatocarcinoma--preliminary analysis].

A pedigree study was carried out in families with hepatocarcinoma (HCC) in Qidong county. The results showed that the incidence of families with familial history of HCC was 41.59% (443/1065). By means of test for Fitness of Binomial Distribution, it was found that HCC had an evident tendency of familial aggregation (P less than 0.01). In the high risk families, the average death age of patients with HCC in filial generation was younger (38.92 years old) than that of people who die of HCC in Qidong county (49.26 years old). The age at which siblings had HCC was often similar: 31.63%, with age-difference less than or equal to 2 years and 61.22%, less than or equal to 5 years. Whether the members of high risk families lived together or not, the incidence of HCC was alike (P greater than 0.05). These results suggest that the role of genetic factors in the etiology of HCC should not be neglected.

Carcinoma, Hepatocellular↗