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At least 973 records · Page 54Linked to original sources
PubMed2000

Effect of pressure and gas type on intraabdominal, subcutaneous, and blood pH in laparoscopy.

BACKGROUND: According to the literature, the number of port-site metastases in laparoscopic surgery varies considerably depending on the type of gas used for the pneumoperitoneum. In order to investigate this observation we studied the changes in blood, subcutaneous, and intra-abdominal pH during laparoscopy with helium, CO(2) and room air in a rat model. In addition, we looked at the influence of intra-abdominal pressure and duration of pneumoperitoneum on the pH during the laparoscopy. METHODS: pH was measured by tonometry, intra-abdominally and subcutaneously. A pH electrode was additionally placed into the subcutaneous tissue and the results compared to those measured by tonometry. Blood samples were taken from a catheter in the carotid artery. The intra-abdominal pressure was 0, 3, 6, 9 mm Hg for 30 min in each case. We investigated the effect of pneumoperitoneum with CO(2), helium and air in randomized groups of 5 rats. In an additional series the pressure was held constant at 3 mm Hg and the pH was measured every 30 min. RESULTS: Due to the different absorption capacity of the peritoneum, laparoscopy with CO(2) decreases the subcutaneous pH from 7.35 to 6.81. Blood pH is reduced from 7.37 to 7.17 and the intra-abdominal pH from 7.35 to 6.24. Other, less absorbable gases induce smaller changes of blood and subcutaneous pH (only 10% of CO(2)). In a variance analysis the p value is less than 0.001. The influence of duration of laparoscopy (30 min vs. 90 min) on the subcutaneous pH is less compared to the influence of intra-abdominal pressure (0, 3, 6, 9 mm Hg). CONCLUSIONS: Depending on the type of gas (CO(2), air, helium) used for laparoscopy blood, subcutaneous and intra-abdominal pH are influenced differently. Because lower pH is known to impair local defense mechanisms, these results may be one explanation for the higher incidence of port-site metastasis in laparoscopy with CO(2) than with other gases, as reported in the literature.

Abdomen↗
PubMed2004

The distribution of symptoms of attention-deficit/hyperactivity disorder and oppositional defiant disorder in school age children in Turkey.

OBJECTIVE: The aim of this study was to determine the prevalence of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) in school age children in Sivas province centre and to examine the distribution of symptoms according to subtypes. METHOD: The study population was made up of 1425 children between the ages of 6 and 15 from eight primary schools selected by random sampling method in Sivas province centre. All students were given a questionnaire prepared according to DSMIV criteria that was completed by their parents or teachers. This form includes 18 symptoms of ADHD and eight symptoms of ODD. Student's t-test and variance analysis were used for statistical evaluation. RESULTS: A prevalence of 8.1% was found for ADHD in our study. According to subtypes, 32.2% of these were "inattentive", 40% were "hyperactive" and 27.8% were combined type. A prevalence of 11.5% was found for ODD. The boy/girl ratio was > 1 for both ADHD and ODD, and 52.2% of those with ADHD were established as having ODD at the same time. CONCLUSIONS: The prevalence of ADHD and ODD in primary school children was not considered to be small. Studies concerning the distribution of symptoms in different societies, cultures, and viewpoints and identification of children with this type of problem are beneficial for early diagnosis and prophylactic treatment.

Adolescent↗
PubMed2002

Acute electrophysiological effect of pulsed gallium-arsenide low-energy laser irradiation on isolated frog sciatic nerve.

We evaluated the acute electrophysiological effects of low-energy pulsed laser irradiation on isolated frog sciatic nerve measured by extracellular recording technique. A pulsed gallium-arsenide (GaAs) laser (wavelength: 904 nm, pulse duration 220 ns, peak power per pulse: 27W, spot size: 0.28 cm(2), total applied energy density: 0.005-2.5J/cm(2)) was used for the experiment. Sixty isolated nerves were divided into six groups (n=10), each of which received a different laser dose. In each group, action potentials were recorded before laser irradiation which served as the control data. The extracellular action potentials were recorded for each combination of 1, 3, 5, 7, 10, 13 and 15 minutes of irradiation time and 4, 8, 16, 32, 64 and 128 repetition frequency by using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara, USA). Action potential amplitude, area, duration and conduction velocity were measured. Statistical evaluation was performed using repeated measures variance analysis by SPSS 9.0. There were no statistically significant differences for action potential amplitude, area and conduction velocity among the laser groups and control data (p>0.05). The study showed that low-energy GaAs irradiation at 4-128 Hz repetition frequencies administered for irradiation times of 1-15 min generates no effect on action potential amplitude, area, duration and conduction velocity in isolated frog sciatic nerve.

Action Potentials↗
PubMed2006

Long-range correlations in rabbit brain neural activity.

We have analyzed the presence of persistence properties in rabbit brain electrical signals by means of non-equilibrium statistical physics tools. To measure long-memory properties of these experimental signals, we have first determined whether the data are fractional Gaussian noise (fGn) or fractional Brownian motion (fBm) by calculating the slope of the power spectral density plot of the series. The results show that the series correspond to fBm. Then, the data were studied by means of the bridge detrended scaled windowed variance analysis, detecting long-term correlation. Three different types of experimental signals have been studied: neural basal activity without stimulation, the response induced by a single flash light stimulus and the average of the activity evoked by 200 flash light stimulations. Analysis of the series revealed the existence of persistent behavior in all cases. Moreover, the results also exhibited an increasing correlation in the level of long-term memory from recordings without stimulation, to one sweep recording or 200 sweeps averaged recordings. Thus, brain neural electrical activity is affected not only by its most recent states, but also by previous states much more distant in the past.

Action Potentials↗
PubMedDate not supplied

The dynamic gene expression from different genetic systems for protein and lysine contents of indica rice.

The dynamic expression of genes for protein and lysine contents of rice grain under different environments was carried out with time-dependent measures by using the developmental genetic models for quantitative traits of triploid endosperm in cereal crops. The results showed that the genetic effects, especially genotype x environment (GE) interaction effects from the genes expression of different genetic systems including triploid endosperm, cytoplasm and diploid maternal plant were important for the performance of both nutrient quality traits at all developmental times/stages of rice grain. The conditional genetic variance analysis found that the activation of quantitative genes especially from endosperm and maternal plant genetic systems for protein and lysine contents was gradually carried through the developmental process of rice grain. The net genetic effects showed that the new expression of quantitative genes for protein and lysine contents was more active at late filling stage (15-21 days after flowering) and maturity stage (22-28 days) of rice grain. Also the sequential expression of cytoplasmic genes cannot be ignorable for the development of nutrient quality traits. The phenomena that some genes could continuously express for several developmental stages or the genes expression could be interrupted among developmental stages of rice grain was detected especially for net endosperm additive main effects or maternal additive main effects. The differences of genetic relationships from different genetic systems were found for protein and lysine contents among developmental times of rice grain.

Diploidy↗
PubMed2006

A depth of anaesthesia index from linear regression of EEG parameters.

OBJECTIVE: The field of Anaesthesia has recently witnessed numerous advances both in the drug administration and monitoring of anaesthetic state. This development has further boosted the efforts and interest of researchers in the automation of clinical Anaesthesia. The success in this direction is possible only when assessment of the depth of hypnotic component of anaesthesia is achieved accurately. This paper describes a technique to arrive at a reliable Depth of Hypnosis (DoH) index using electroencephalographic (EEG) parameters. METHODS: EEG data from nine patients was recorded and processed to obtain a total of 21 EEG parameters. They were reduced to a set of best five parameters after applying graphical variance analysis which evaluates their power to discriminate between awake and unresponsive states. These five parameters were normalized with respect to awake state and used in a first order equation to give DoH index. RESULTS: The value of computed DoH index varied from 0.37 to 0.58 for different patients during anesthetized state (awake value 1). For a single patient, the maximum variation in the index was observed as +/- 5% for different epochs at constant dose. CONCLUSIONS: A combination of irregularity of EEG waveform in time-domain and band powers in frequency domain best describes the difference between awake and anesthetized states. To characterize these states, a set of optimum EEG parameters exists. These parameters must be normalized to reduce interpatient variability. The calculated graded index may be used to assist the anaesthetist in the operating theatre.

Adult↗
PubMed2005

Comparison of two different ecarin clotting time methods.

BACKGROUND: Ecarin Clotting Time (ECT) assay specifically determines the inhibition of meizothrombin by direct thrombin inhibitors (DTI). Blood coagulation factor levels lowered by vitamin K antagonists (VKA) may prolong ECT. Concomitant treatment of VKA with DTI may influence differently the two published ECT methods. METHODS: Lepirudin (100-3,000 ng/ml), argatroban (300--3,000 ng/ml) and melagatran (30--1000 ng/ml) were added to normal plasma (NP; n=12) samples and to plasma of patients on stable vitamin K antagonist therapy with warfarin (VKAP; n=12). ECT assays were performed according to [5] (method 1) and according to [6] (method 2). Data were subjected to multifactorial variance analysis. RESULTS: Normal ranges were 35.5+/-2.8 s in NP versus 31.8+/-1.2 s in VKAP with method 1 (p< 0.001) and 44.3+/-3.9 s in NP vs. 51.4+/-8.3 s in VKAP with method 2 (p< 0.004). Besides the inhibitors (p<0.0001), the method used (p<0.0001) and the group (NP vs. VKAP, p=0.003) had an influence on the ECT. Inhibitors (p< 0.02) or method used (p< 0.03) and the group (NP vs. VKAP, p=0.0001) influenced also the ECT ratio. DISCUSSION: Both ECT methods are suitable for monitoring different DTIs over a large linear range with both methods during concomitant treatments with vitamin K antagonists. The ECT ratio improves but not abolishes the differences between the methods. Additive effects of vitamin K antagonists on ECT methods have to be taken into consideration in clinical routine.

Antithrombins↗
PubMed1994

Associations of social and demographic variables with calcium intakes of high school students.

OBJECTIVE: To assess usual calcium intake of urban high school students and to assess the association of social and demographic variables with calcium intake. DESIGN: A self-administered survey instrument containing the following elements: a food frequency questionnaire (FFQ) developed to estimate calcium intake; questions to elicit demographic information; and scales to reflect taste enjoyment of dairy products, social reinforcement for consumption of milk, perceptions of others' opinions about milk, and behavioral modeling of milk consumption (ie, the frequency of observing friends' and family members' use of milk). The FFQ was shown to include major sources of calcium in diets of a pretest sample (n = 130). SETTING: Urban high schools in a metropolitan setting. SUBJECTS/SAMPLES: Students in one class per grade level in six high schools (approximately 900 students) were asked to participate. Of the 856 questionnaires completed, 785 were usable. MAIN OUTCOME MEASURES: Total calcium intake, as estimated using the FFQ. STATISTICAL ANALYSES PERFORMED: Descriptive statistics, t tests, one-way analysis of variance, correlation analysis, and stepwise multiple regression analysis were used to assess relationships of independent variables with calcium intake. RESULTS: Mean estimated calcium intakes for male and female students were 1,146 +/- 41 mg/day (mean +/- standard error of the mean) and 815 +/- 26 mg/day (P < .001), respectively, 59% of which was obtained from milk. Median intakes were 1,016 mg/day for boys and 676 mg/day for girls, and more than half the students had intakes that were below current recommendations. Multiple regression analysis revealed significant predictors of total calcium intake: gender (boys > girls); taste enjoyment of dairy products; number of meals and snacks per day; age; ethnicity (whites > Asians); behavioral modeling of milk consumption; perceptions of others' opinions, recommendations, and use of milk; and soft drink consumption (total adjusted R2 = .304). With the exception of age, these variables were positively associated with calcium intake. Regression equations developed for boys and girls separately revealed that different variables entered the equations. APPLICATIONS/CONCLUSIONS: Most of the variability in adolescents calcium intakes remained unexplained by the variables included in this study. Nevertheless, the results suggest that education programs focusing on taste enjoyment of dairy products and building on the influence of peers and family members may have a positive impact on calcium intake.

Adolescent↗
PubMed1987

Antihypertensive effect of sustained-release isosorbide dinitrate for isolated systolic systemic hypertension in the elderly.

A double-blind, randomized trial was performed in 40 patients, mean age (+/- standard deviation) 80 +/- 4 years, with isolated systolic systemic hypertension to evaluate the antihypertensive effect of oral sustained-release isosorbide dinitrate (ISDN), 20 to 40 mg twice daily, vs placebo. After 12 weeks of treatment, supine systolic blood pressure (BP) decreased from 192 +/- 10 to 162 +/- 12 mm Hg with ISDN (p less than 0.001) and from 189 +/- 10 to 175 +/- 15 mm Hg with placebo (p less than 0.001). On the basis of variance analysis, the decrease in systolic BP was significantly lower with ISDN (27 mm Hg) than with placebo (13 mm Hg). Similar results were observed for supine and erect systolic BP measured at 8 AM and 4 PM, 8 and 12 hours after drug intake. No significant differences in diastolic BP, heart rate or side effects occurred. After the ISDN tapering off-period (2 weeks), systolic BP increased significantly but did not change with placebo. The study provided evidence that in elderly patients with systolic hypertension, sustained-release ISDN induced a selective and sustained decrease in systolic BP, antihypertensive effect was observed 8 and 12 hours after drug administration, and no tolerance phenomenon was noted.

Aged↗
PubMed1991

Effects of aerobic exercise training on symptomatic women with mitral valve prolapse.

The effects of a 12-week aerobic exercise training protocol on 32 symptomatic women with mitral valve prolapse were studied. Subjects were randomly assigned to control or exercise groups. Exercise subjects completed a 12-week (3 times per week) exercise training program based on guidelines established by the American Heart Association for phase II cardiac rehabilitation programs; control group subjects maintained normal activities. Before and after training, subjects underwent maximal multistage treadmill testing, and measurements were obtained for plasma catecholamine levels at rest and during peak exercise; they completed the State Trait Anxiety Inventory and General Well-Being Schedule. Weekly symptom frequency of chest pain, arm pain, palpitations, shortness of breath, fatigue, headache, mood swings, dizziness and syncope were monitored for the 12-week period. Data were analyzed using multivariate analysis of variance, multivariate analysis of covariance, and analysis of covariance with repeated measures. Compared with control subjects, the exercise group showed a significant (p less than 0.05) decrease in State Trait Anxiety Inventory scores, an increase in General Well-Being scores, an increase in functional capacity and a decline in the frequency of chest pain, fatigue, dizziness and mood swings. No statistically significant differences were noted in catecholamine levels at rest or during peak exercise. These findings support the use of aerobic exercise in the management of symptomatic women with mitral valve prolapse.

Adult↗
PubMed1989

Reproductive outcome in women who lost their husbands in the course of pregnancy.

The loss of a husband in the course of pregnancy represents a serious life event that is accompanied by important psychosocial stress. We compared the length of pregnancy and the weight of the newborns in women who were widowed in the course of their pregnancy with control groups of married and unmarried women of the same parity and delivering in the same institute. The group of widowed parturients consisted of 40 women. The control group of married women included 38 cases, and the control group of unmarried women consisted of 33 cases. The results were statistically evaluated by means of variance analysis and sequential pair t-test. The average length of pregnancy was in the widowed women 279.46 +/- 8.54 days, in married women 277.13 +/- 10.9 days and in unmarried women 273.91 +/- 16.17 days. The differences are not statistically significant. The average weight of the newborn was 3327.0 +/- 484.98 g in the widowed women, 3347.11 +/- 404.76 g in married women and 3068.18 +/- 543.79 g in unmarried women. The weights of the newborns of widowed and married women are not different, but both are significantly higher than in the unmarried women (p less than 0.05). The results do not confirm the influence of psychosocial stress due to life events occurring in the course of pregnancy upon the length of the pregnancy and the weight of the newborn.

Adult↗
PubMed1995

Evidence for a global scanpath strategy in viewing abstract compared with realistic images.

Scanpaths, the repetitive sequences of saccadic eye movements, occurred when subjects viewed slide projections of both realistic and abstract art. Variance analysis demonstrated that global/local eye movement indices were lower for local scanning by professional art viewers who relied on more global viewing, particularly in abstract images. Non-professional, unsophisticated subjects carried their local scanpath patterns from realistic images on to abstract images. The blink rate of professional subjects viewing abstract images was also significantly lower, indicating increased visual effort. Non-professional viewers showed no difference in blink rates.

Adult↗
PubMed1995

Oscillating prostacyclin and thromboxane generation by human vessels: biological and mathematical evidence for negative feedback control.

The presented study investigates the time-dependent release of PGI2 and TXA2 by isolated human umbilical veins in vitro using the radioimmunoassay for measurement. After changing the nutritional fluid--Krebs-Henseleit solution at pH 7.4, 37 degrees C, 95% O2/5% CO2--the release graph oscillates. These oscillations with time were verified by variance analysis and are very similar for both substances. This indicates one or several negative feedback mechanisms acting on the common path of synthesis from the membrane-bound phospholipids to PGH2, which are effective in the regulation of eicosanoid biosynthesis in vitro. A mathematical function describing the observed PGI2 and TXA2 synthesis is communicated.

Embryo, Mammalian↗
PubMed1988

Variations of plasma immunoreactive motilin, pancreatic polypeptide, gastrin and somatostatin along the duodenal motility cycle in the pig.

The peripheral plasma concentrations of immunoreactive motilin, pancreatic polypeptide (PP), somatostatin and gastrin were measured in 7 pigs fasted to 24 h and subsequently fed a standard meal. Plasma motilin peaked during the last part of phase II activity of the migrating myoelectric complex (MMC) sequence (25.2 +/- 2.3 pM), the lowest value being recorded during phase I (10.6 +/- 1.5 pM) after a 24 h fast. Plasma motilin remained at a low level during the digestive pattern of duodenal activity, no fluctuation occurring when the first postprandial MMC recurred. At variance analysis, gastrin and PP were not released phasically with MMC in the fasting state, while at autocovariance both peptides tended to fluctuate during the MMC sequence with positive and negative peaks at regular intervals along MMC cycles. No variation of plasma somatostatin was observed in the fasting animals. These findings argue against a major role of circulating PP, gastrin and somatostatin-like components in the control of fasted and post absorptive duodenal motility in pigs while the role of motilin remains equivocal.

Animals↗
PubMedDate not supplied

Prognostic role of serum albumin and prealbumin levels in elderly patients at admission to a geriatric hospital.

The incidence of biological malnutrition is very high in geriatric hospitalized patients. The aim of the present study was to investigate the nutritional status of elderly patients at the time of hospital admission in an effort to identify variables which influence the outcome of hospital stay. Forty-six percent (244/552) of the admitted patients had a serum albumin level less than 35 g/l. Cancer patients had a significantly (p < 0.0001) lower serum albumin and prealbumin values than other patients. The patients, who died, had even lower albumin values as compared to the cancer patients. None of the studied nutritional and social parameters showed correlation with the length of hospital stay in any group of patients. No significant correlation could be found between age and nutritional values. No significant correlation could be established between the social parameters and nutritional variables. By using variance analysis statistically significant association was found between cancer and serum albumin (p < 0.0001) as well as between the death occurring during the hospital stay and nutritional values (p < 0.0001). By the discriminant analysis model, the mortality during hospital stay could be predicted with 78.8% certainty when the presence of cancer, the albumin and prealbumin values were known. In addition, cancer status may be suspected in the case of low nutritional values at admission in these elderly patients. Our results indicate that by the measurement of these simple parameters an accurate prediction can be achieved in the prognosis of hospitalized geriatric patients already at the time of admission.

Journal Article↗
PubMed1982

Estimation of the three-dimensional wall thickness of completed remodeling sites in iliac trabecular bone.

The wall thickness of completed remodeling sites in trabecular bone was estimated in 25 normal individuals and 5 patients with arthrosis of the knee, using 7 micron sections of undecalcified iliac crest bone. A systematic sampling procedure which gives a surface referent estimate of the thickness was applied. The efficiency of the sampling design was optimized by means of a cost-variance analysis. The proposed method of sampling which eliminates a common bias in bone histomorphometry is recommended for determinations of wall thickness, osteoid thickness, lamellar thickness, and distance between fluorochrome markers in trabecular bone. The intraindividual distributions of three-dimensional wall thickness were reconstructed from the measurements of apparent width by an unfolding procedure based on the geometric probability density function pertaining to randomly sectioned plates. Distributions of true wall thickness for the young normal individuals were unimodal and resembled normal distributions. The three-dimensional mean wall thickness was 61.4 +/- 4.4 micron (+/- SD). It was demonstrated that the conventionally applied stereological transformation, which calculates the three-dimensional mean wall thickness from the mean apparent width by multiplying the latter by pi/4, underestimates the three-dimensional mean wall thickness. An improved transformation is illustrated and is recommended for estimating three-dimensional mean thickness of plates from two-dimensional measurements in trabecular bone.

Adult↗
PubMed1982

Arm anthropometry in a large reference population and in surgical patients.

Triceps skinfold (TSF) and midarm circumference (MAC) were measured and the arm muscle circumference (AMC) calculated in 1860 healthy persons aged between 20 and 101 years and because the distribution of our findings was not Gaussian we have used the 5th and 10th percentiles instead of standard deviation to define limits between severe and moderate malnutrition and between moderate malnutrition and normal. One-way variance analysis showed significant increases in TSF in women from the 3rd (mean 18.3 mm) to the 6th (mean 23.6 mm) decades (p<0.05 - 0.001). No variation was seen in the 6th and 7th decades but thereafter decreases occurred to the 10th (mean 14.4 mm) decade (p<0.05 - 0.001). In men, TSF showed no variation from the 3rd (mean 10.8 mm) to the 9th (mean 10.6 mm) decades but in the 10th (mean 9.4 mm) decade it decreased significantly (p<0.05). In women, AMC increased from the 3rd (mean 21.1 cm) to the 6th (mean 22.1 cm) decades (p<0.05 - 0.001). No variation was seen from the 6th to 8th decades, but thereafter decreases occurred to the 10th (mean 20.2 cm) decade (p<0.05 - 0.001). In men no variation was seen in AMC from the 3rd (mean 26.2 cm) to the 7th (mean 25.9 cm) decades, but decreases were shown to the 10th (mean 23.0 cm) decade (p<0.001). Using these values in 112 surgical patients, 26 per cent showed signs of malnutrition in their fat stores and 6 per cent in muscle. The wide variation in anthropometric measurements between different age groups precludes the use of a mean reference value covering all ages in the assessment of malnutrition.

Journal Article↗
PubMed1990

Prophylactic activity of dihydroheptaprenol, a synthetic polyprenol derivative, against Sendai virus infection in mice.

The effect of a chemically synthesized polyprenol derivative, dihydroheptaprenol (DHP), on the non-specific resistance of mice to Sendai virus infection was investigated. The mice that received 200 micrograms of DHP intranasally twice, at 3 days and 1 day before the infection, showed a significant protection against Sendai virus infection. Treatment of mice twice even with as much as 2000 micrograms of DHP through the subcutaneous route, however, had no protective effect against infection. Excess interferon and tumour necrosis factor production in intranasally DHP-treated mice was seen 1 day after the infection when compared with Sendai virus alone controls or with DHP alone controls. Variance analysis of these findings indicates a prophylactic activity of DHP in pulmonary viral infections.

Administration, Intranasal↗