989 resultados para Hartree Fock scheme correlation errors


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Cirrhotic patients (23 with alcoholic cirrhosis, 5 with posthepatitic cirrhosis and 2 with cryptogenic cirrhosis) with ascites and portal hypertension were studied and divided into two groups corresponding to high or low risk to develop spontaneous bacterial peritonitis (SBP) related to the concentration of total protein in the ascitic fluid (A-TP): group I (high risk): A-TP£1.5 g/dl and group II (low risk): A-TP>1.5 g/dl. Fibronectin (FN), C3 and C4 concentrations were measured by radial immunodiffusion while total protein was measured by the biuret method. The mean values (group I vs group II) of C3 (12.59 ± 4.72 vs 24.53 ± 15.58 mg/dl), C4 (4.26 ± 3.87 vs 7.26 ± 4.14 mg/dl) and FN (50.47 ± 12.49 vs 75.89 ± 24.70 mg/dl) in the ascitic fluid were significantly lower (P<0.05) in the group considered to be at high risk for SBP. No significant difference was observed in the plasma/ascites fibronectin ratio (3.91 ± 1.21 vs 3.80 ± 1.26) or gradient (131.46 ± 64.01 vs 196.96 ± 57.38) between groups. Fibronectin in ascites was significantly correlated to C3 (r = 0.76), C4 (r = 0.58), total protein (r = 0.73) and plasma FN (r = 0.58) (P<0.05). The data suggest that the FN concentration in ascites is related to the opsonic capacity of this fluid, and that its concentration in the ascitic fluid may be a biochemical risk factor indicator for the development of spontaneous bacterial peritonitis

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The pathogenesis of protracted diarrhea is multifactorial. In developing countries, intestinal infectious processes seem to play an important role in triggering the syndrome. Thirty-four children aged 1 to 14 months, mean 6.5 months, with protracted diarrhea were studied clinically and in terms of small intestinal mucosal morphology. Mild, moderate or severe hypotrophy of the jejunal mucosa was detected in 82% of cases, and mucosal atrophy was observed in 12%. The intensity of the morphological changes of the jejunal mucosa correlated negatively with serum albumin levels. No correlation was detected between mucosal grading and duration of diarrhea or between mucosal grading and weight reported as percentile. After nutritional support was instituted, serial jejunal biopsies were obtained from 12 patients: five patients submitted to parenteral nutrition for 7 to 38 days, mean 17 days, and 7 patients receiving a hypoallergenic oral diet (semi-elemental formula, 3; chicken formula, 3; human milk, 1). In seven cases (58%) a progressive increase in villus height and a decrease in the number of inflammatory cells were noted. Recovery of the morphologic pattern was accompanied by clinical improvement in all patients

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Fractures are the feared consequences of osteoporosis and fractures of the proximal femur (FPF) are those that involve the highest morbidity and mortality. Thus far, evaluation of bone mineral density (BMD) is the best way to determine the risk of fracture. Genetic inheritance, in turn, is one of the major determinants of BMD. A correlation between different genotypes of the vitamin D receptor (VDR) and BMD has been recently reported. On this basis, we decided to determine the importance of the determination of VDR genotype in the presence of an osteoporotic FPF in a Brazilian population. We studied three groups: group I consisted of 73 elderly subjects older than 65 years (78.5 ± 7.2 years) hospitalized for nonpathological FPF; group II consisted of 50 individuals older than 65 years (72.9 ± 5.2 years) without FPF and group III consisted of 98 young normal Brazilian individuals aged 32.6 ± 6.6 years (mean ± SD). Analysis of VDR gene polymorphism by restriction fragment length polymorphism (RFLP) was performed by PCR amplification followed by BsmI digestion of DNA isolated from peripheral leukocytes. The genotype distribution in group I was 20.5% BB, 42.5% Bb and 37% bb and did not differ significantly from the values obtained for group II (16% BB, 36% Bb and 48% bb) or for group III (10.2% BB, 47.6% Bb and 41.8% bb). No differences in genotype distribution were observed between sexes or between the young and elderly groups. We conclude that determination of VDR polymorphism is of no practical use for the prediction of FPF. Other nongenetic factors probably start to affect bone mass, the risk to fall and consequently the occurrence of osteoporotic fractures with advancing age.

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Adult Channa punctatus murrels of both sexes (60-80 g) were collected locally from Ramgarh Lake during the second week of every month (10 individuals of each sex/month) throughout the year. Blood samples were collected and analyzed for serum calcium and phosphate levels by the methods of Trinder (1960) and Fiske and Subbarow (1925), respectively. Gonads were fixed to judge the state of maturation of the fish. Males exhibited no change in serum calcium levels throughout the year in correlation with testicular maturation. However, serum phosphate levels exhibited a rise in correlation with the increased gonadosomatic index. Females showed marked seasonal changes in serum calcium and phosphate levels which were associated with ovarian maturation (vitellogenesis).

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Theta rhythm in many brain structures characterizes wakefulness and desynchronized sleep in most subprimate mammalian brains. In close relation to behaviors, theta frequency and voltage undergo a fine modulation which may involve mobilization of dorsal raphe nucleus efferent pathways. In the present study we analyzed frequency modulation (through instantaneous frequency variation) of theta waves occurring in three cortical areas, in hippocampal CA1 and in the dorsal raphe nucleus of Wistar rats during normal wakefulness and after injection of the 5-HT1a receptor agonist 8-OH-DPAT into the dorsal raphe. We demonstrated that in attentive states the variation of theta frequency among the above structures is highly congruent, whereas after 8-OH-DPAT injection, although regular signals are present, the variation is much more complex and shows no relation to behaviors. Such functional uncoupling after blockade demonstrates the influence of dorsal raphe nucleus efferent serotoninergic fibers on the organization of alertness, as evaluated by electro-oscillographic analysis.

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The aim of this study was to analyze the thickness of the intima-media complex (IMC) using a noninvasive method. The carotid and femoral common arteries were evaluated by noninvasive B-mode ultrasound in 63 normotensive and in 52 hypertensive subjects and the thickness of the IMC was tested for correlation with blood pressure, cardiac structures and several clinical and biological parameters. The IMC was thicker in hypertensive than in normotensive subjects (0.67 ± 0.13 and 0.62 ± 0.16 vs 0.54 ± 0.09 and 0.52 ± 0.11 mm, respectively, P<0.0001). In normotensive patients, the simple linear regression showed significant correlations between IMC and age, body mass index and 24-h systolic blood pressure for both the carotid and femoral arteries. In hypertensives the carotid IMC was correlated with age and 24-h systolic blood pressure while femoral IMC was correlated only with 24-h diastolic blood pressure. Forward stepwise regression showed that age, body mass index and 24-h systolic blood pressure influenced the carotid IMC relationship (r2 = 0.39) in normotensives. On the other hand, the femoral IMC relationship was influenced by 24-h systolic blood pressure and age (r2 = 0.40). In hypertensives, age and 24-h systolic blood pressure were the most important determinants of carotid IMC (r2 = 0.37), while femoral IMC was influenced only by 24-h diastolic blood pressure (r2 = 0.10). There was an association between carotid IMC and echocardiographic findings in normotensives, while in hypertensives only the left posterior wall and interventricular septum were associated with femoral IMC. We conclude that age and blood pressure influence the intima-media thickness, while echocardiographic changes are associated with the IMC.

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Naomi Shinomiya Hell was the first researcher to investigate the physiological adaptations to a meal-feeding scheme (MFS) in Brazil. Over a period of 20 years, from 1979 to 1999, Naomi's group determined the physiological and metabolic adaptations induced by this feeding scheme in rats. The group showed the persistence of such adaptations even when MFS is associated with moderate exercise training and the performance to a session of intense physical effort. The metabolic changes induced by the feeding training were discriminated from those caused by the effective fasting period. Naomi made an important contribution to the understanding of the MFS but a lot still has to be done. One crucial question still remains to be satisfactorily answered: what is the ideal control for the MFS?

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The purpose of the present study was to investigate the expression (mRNA) of CD40 ligand (CD40L), interferon-gamma (IFN-gamma) and Fas ligand (FasL) genes in human cardiac allografts in relation to the occurrence of acute cardiac allograft rejection as well as its possible value in predicting acute rejection. The mRNA levels were determined by a semiquantitative reverse transcriptase-polymerase chain reaction method in 39 samples of endomyocardial biopsies obtained from 10 adult cardiac transplant recipients within the first six months after transplantation. Biopsies with ongoing acute rejection showed significantly higher CD40L, IFN-gamma and FasL mRNA expression than biopsies without rejection. The median values of mRNA expression in biopsies with and without rejection were 0.116 and zero for CD40L (P<0.003), 0.080 and zero for IFN-gamma (P<0.0009), and 0.156 and zero for FasL (P<0.002), respectively. In addition, the levels of IFN-gamma mRNA were significantly increased 7 to 15 days before the appearance of histological evidence of rejection (median of 0.086 in pre-rejection biopsies), i.e., they presented a predictive value. This study provides further evidence of heightened expression of immune activation genes during rejection and shows that some of these markers may present predictive value for the occurrence of acute rejection.

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The purpose of the present study was to evaluate the mixed lymphocyte culture as a predictive assay of acute and chronic graft-versus-host disease (GVHD). We studied 153 patients who received a first bone marrow transplantation from human leukocyte antigen-identical siblings. Acute GVHD was observed in 26 of 128 (20.3%) patients evaluated and chronic GVHD occurred in 60 of 114 (52.6%). One-way mixed lymphocyte culture (MLC) assays were performed by the standard method. MLC results are reported as the relative response (RR) from donor against patient cells. The responses ranged from -47.0 to 40.7%, with a median of 0.5%. The Kaplan-Meier probability of developing GVHD was determined for patients with positive and negative MLC. There was no significant difference in incidence of acute GVHD between the groups studied. However, the incidence of chronic GVHD was higher in recipients with RR >4.5% than in those with RR <=4.5%. The Cox Proportional Hazards model was used to examine the effect of MLC levels on incidence of chronic GVHD, while adjusting for the potential confounding effect of others suspected or observed risk factors. The relative risk of chronic GVHD was 2.5 for patients with positive MLC (RR >4.5%), 2.9 for those who received peripheral blood progenitor cells as a graft, and 2.2 for patients who developed previous acute GVHD. MLC was not useful for predicting acute GVHD, but MLC with RR >4.5% associated with other risk factors could predict the development of chronic GVHD, being of help for the prevention and/or treatment of this late complication.

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Osteoporosis is a multifactorial disease with great impact on morbidity and mortality mainly in postmenopausal women. Although it is recognized that factors related to life-style and habits may influence bone mass formation leading to greater or lower bone mass, more than 85% of the variation in bone mineral density (BMD) is genetically determined. The collagen type I alpha 1 (COLIA1) gene is a possible risk factor for osteoporosis. We studied a population of 220 young women from the city of São Paulo, Brazil, with respect to BMD and its correlation with both COLIA1 genotype and clinical aspects. The distribution of COLIA1 genotype SS, Ss and ss in the population studied was 73.6, 24.1 and 2.3%, respectively. No association between these genotypes and femoral or lumbar spine BMD was detected. There was a positive association between lumbar spine BMD and weight (P<0.0001), height (P<0.0156), and body mass index (BMI) (P<0.0156), and a negative association with age at menarche (P<0.0026). There was also a positive association between femoral BMD and weight (P<0.0001), height (P<0.0001), and BMI (P<0.0001), and a negative correlation with family history for osteoporosis (P<0.041). There was no association between the presence of allele s and reduced BMD. We conclude that a family history of osteoporosis and age at menarche are factors that may influence bone mass in our population.

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This thesis estimates long-run time variant conditional correlation between stock and bond returns of CIVETS (Colombia, Indonesia, Vietnam, Egypt, Turkey, and South Africa) nations. Further, aims to analyse the presence of asymmetric volatility effect in both asset returns, as well as, obverses increment or decrement in conditional correlation during pre-crisis and crisis period, which lead to make a reliable diversification decision. The Constant Conditional Correlation (CCC) GARCH model of Bollerslev (1990), the Dynamic Conditional Correlation (DCC) GARCH model (Engle 2002), and the Asymmetric Dynamic Conditional Correlation (ADCC) GARCH model of Cappiello, Engle, and Sheppard (2006) were implemented in the study. The analyses present strong evidence of time-varying conditional correlation in CIVETS markets, excluding Vietnam, during 2005-2013. In addition, negative innovation effects were found in both conditional variance and correlation of the asset returns. The results of this study recommend investors to include financial assets from these markets in portfolios, in order to obtain better stock-bond diversification benefits, especially during high volatility periods.

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Deficiency of 21-hydroxylase is the most common form of congenital adrenal hyperplasia (CAH-21OH). We determined by allele-specific PCR the frequency of microconversion in the CYP21A2 gene in 50 Brazilian patients with the classical (salt wasting: SW and simple virilizing: SV) forms and nonclassical (NC) form of CAH-21OH and correlated genotype with phenotype. Genotypes were classified into three mutation groups (A, B, and C) based on the amount of enzymatic activity in in vitro studies using adrenal cells. In 94 unrelated alleles, we diagnosed 76% of the affected alleles after screening for 7 microconversions. The most frequent point mutations observed in this series were I172N (19%), V281L (18%), and IVS2,A/C>G,-12 (15%). In the SW form, the most frequent mutation was IVS2,A/C>G,-12 (38%), in the SV form it was I172N (53%), and in the NC form it was V281L (57.7%). We observed a good correlation between genotype and phenotype. Discordance between genotype and phenotype was found in one SV patient with a mild mutation in one of the alleles (R356W/V281L). However, we cannot rule out the presence of an additional mutation in these alleles. We also observed a good correlation of genotype with 17alpha-hydroxyprogesterone, testosterone, and androstenedione levels. The severity of external genitalia virilization correlated with the severity of mutation. In conclusion, the frequencies described in the present study did not differ from worldwide studies, including the Brazilian population. The few differences observed may reflect individual sample variations. This new Brazilian cohort study suggests the presence of new mutations in Brazilian patients with different forms of CAH-21OH.

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During routine investigations, we are surprised to find that therapy for bone metastases is sometimes delayed for a considerable period of time. To determine the extent of this delay and its causes, we reviewed the medical records of symptomatic patients seen at our hospital who had been recently diagnosed as having bone metastases for the last four years. The treatment delay was defined as the interval between presentation with symptoms and definitive treatment for bone metastases. The diagnostic delay was defined as the interval between presentation with symptoms and diagnosis of bone metastases. The results of diagnostic radiological examinations were also reviewed for errors. The study population included 76 males and 34 females with a median age of 66 years. Most bone metastases were diagnosed radiologically. Over 75% of patients were treated with radiotherapy. The treatment delay ranged from 2 to 307 days, with a mean of 53.3 days. In 490 radiological studies reviewed, we identified 166 (33.9%) errors concerning 62 (56.4%) patients. The diagnostic delay was significantly longer for patients with radiological errors than for patients without radiological errors (P < 0.001), and much of it was due to radiological errors. In conclusion, the treatment delay in patients with symptomatic bone metastases was much longer than expected, and much of it was caused by radiological errors. Considerable efforts should therefore be made to more carefully examine the radiological studies in order to ensure prompt treatment of bone metastases.

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Extensive literature shows that analysts’ forecasts and recommendations are often biased. Thus, it is important for the financial market to be able to recognize this bias to be able to correctly valuate public companies. This thesis uses characteristic approach, which was introduced by So (2013, pp. 615-640), to forecast analysts’ forecast errors and tests if predictable forecast error is fully incorporated into share prices. Data is collected of listed Finnish companies. Thesis’ timeframe spans over ten years from 2004 to 2013 consisting of 788 firm-years. Although there is earlier evidence that the characteristic approach is able to predict analysts’ forecast errors, no support for this is found in the Finnish market. This thesis contributes to the current knowledge by showing that the characteristic approach does not work universally as such but requires development to work especially in the smaller markets.

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Several investigators have identified Epstein-Barr virus (EBV) particles in breast carcinomas, a fact that supports a role for EBV in mammary tumorigenesis. The possible mechanism involved in this process is not clear. The present study was carried out in an attempt to determine whether there is a relationship between latent infection with EBV and p53 and p63 expression in breast carcinomas. Immunohistochemistry developed with 3.3-diaminobenzidine tetrahydrochloride was performed in 85 formalin-fixed paraffin-embedded breast carcinomas using anti-EBV EBNA-1, anti-p63, anti-p53, anti-estrogen receptor (ER) and anti-progesterone receptor (PR) antibodies. The cases were selected to represent each of the various histologic types: intraductal carcinoma (N = 12), grade I invasive ductal carcinoma (N = 15), grade II invasive ductal carcinoma (N = 15), grade III invasive ductal carcinoma (N = 15), tubular carcinoma (N = 8), lobular carcinoma (N = 10), and medullary carcinoma (N = 10). The ductal breast carcinomas were graded I, II and III based on the Scarff-Bloom and Richardson grading system modified by Elston and Ellis. One slide containing at least 1000 neoplastic cells was examined in each case. ER, PR, p63, p53 and EBNA-1 were positive in 60, 40, 11.8, 21.2 and 37.6% of carcinomas, respectively. There was a correlation between EBNA-1 and p63 expression (P < 0.001), but not between EBNA-1 and p53 (P = 0.10). These data suggest a possible role for p63 in the mammary tumorigenesis associated with Epstein-Barr virus infection.