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An anatomical study of 50 fresh adult human cadavers was performed in order to verify prevalence of Galen's anastomosis (GA) and to evaluate whether factors such as gender, ethnicity, side of the neck, and individual stature may interfere with GA prevalence. The results were analysed using the Chi-square test, Student t-test, and F-Snedecor test. GA was observed in 87 of 100 dissections. There was no statistically significant difference regarding GA prevalence between groups separated by ethnicity (p = 0.853), gender (p = 0.198), side of the neck (p = 0.766), or individual height (p = 0.199). Therefore, the GA was a frequent anatomical finding, and this result was not influenced by any studied factor. Comparing our data with previous studies, we also concluded that the GA seems to play an important role in the innervation of the larynx, even though its function remains unclear. Also, it is reasonable to consider GA a constant anatomical constituent.  相似文献   
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BACKGROUND: Several tumor factors are associated with papillary thyroid cancer. Most studies do not compare the expressions of these factors in the primary tumors and in their associated cervical metastasis. METHODS: Paraffin sections of 20 patients with papillary carcinoma of the thyroid gland with lymph node metastasis were studied. The presence and distribution of insulin-like growth factor I (IGF-I) and proliferating cell nuclear antigen (PCNA) was analyzed, through immunohistochemical technique, in both primaries and lymph node metastasis. The results were correlated with clinical-pathologic data (sex, age, size of primary, multicentricity, thyroid capsule invasion, lymphatic and blood vessels invasion, development of distant metastasis, and associated thyroid diseases). RESULTS: The qualitative analysis showed the reaction for IGF-I was present in more than 90% of the neoplastic cells in both primaries and lymph node metastasis. No correlation with the clinical-pathological features was observed. Regarding the PCNA, the mean percentage of nuclei stained showed no statistical difference between primaries and metastasis (p = 0.598). Except for age, clinicopathologic data had no influence on the mean percentage of nuclei stained. A correlation was verified between the percentage of cells stained by PCNA in primary tumors and the patients' age (p < 0. 01). CONCLUSIONS: The expressions of these tumor factors are equally intense for both primary and metastatic tissue in papillary thyroid cancer. Despite the small size of the sample, the expressions of IGF-I and PCNA could not be associated to clinical-pathologic features, except for the age. As patients over 40 years old had higher expression of PCNA, this marker may have prognostic significance for patients with papillary thyroid cancer.  相似文献   
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This study aimed at formulating simplified estimates of ion-activity products of calcium oxalate (AP(CaOx)) and calcium phosphate (AP(CaP)) in mouse urineto find the most important determinants in order to limit the analytical work-up. Literature data on mouse urine composition was used to determine the relative effect of each urine variable on the two ion-activity products. AP(CaOx) and AP(CaP) were calculated by iterative approximation with the EQUIL2 computerized program. The most important determinants for AP(CaOx) were calcium, oxalate and citrate and for AP(CaP) calcium, phosphate, citrate, magnesium and pH. Urine concentrations of the variables were used. A simplified estimate of AP(CaOx) (AP(CaOx)-index(MOUSE)) that numerically approximately corresponded to 10(8) × AP(CaOx) was given the following expression:[Formula: see text]For a series of urine samples with various composition the coefficient of correlation between AP(CaOx)-index(MOUSE) and 10(8) × AP(CaOx) was 0.99 (p = 0.00000). A similar estimate of AP(CaP) (AP(CaP)-index(MOUSE)) was formulated so that it approximately would correspond numerically to 10(14) × AP(CaP) taking the following form:[Formula: see text]For a series of variations in urine composition the coefficient of correlation was 0.95 (p = 0.00000). The two approximate estimates shown in this article are simplified expressions of AP(CaOx) and AP(CaP). The intention of these theoretical calculations was not to get methods for accurate information on the saturation levels in urine, but to have mathematical tools useful for rough conclusions on the outcome of different experimental situations in mice. It needs to be emphasized that the accuracy will be negatively influenced if urine variables not included in the formulas differ very much from basic concentrations.  相似文献   
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Hepatitis E virus (HEV) causes acute and chronic hepatitis in organ transplant recipients. Serological evidence for HEV infection has been discovered in various population groups in Brazil, and a single acute case has been confirmed. To date, however, no cases of HEV infection in immunocompromised patients have been reported in Brazil. This study aimed to identify and characterize hepatitis E cases in renal transplant recipients in Brazil. A retrospective study was performed on 96 serum samples from renal transplant recipients with unexplained liver enzymes elevation. Three confirmed cases of HEV infection were identified that lacked seroconversion to HEV IgG antibodies. The prevalence of HEV in these patients was 3.1%. Using a sequence analysis of a 304‐nucleotide fragment within ORF2, the strains were classified as genotype 3 with a low percent identity to previously characterized strains. This is the first report of hepatitis E infection in renal transplant recipients in Brazil, and the data indicate that a novel genotype 3 subvariant may be present and that further investigation is necessary to characterize the circulating HEV strains. In this setting, HEV infection should be considered as a potential cause of abnormal liver tests of unknown origin. J. Med. Virol. 85:615–619, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
16.

Objective

To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality.

Methods

Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed.

Results

360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766.

Conclusion

The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality.  相似文献   
17.
BACKGROUND: Obesity is one of the worlds greatest health problems. The Roux-en-Y gastric bypass is the gold standard treatment for severe obesity. Surgery in obese patients has an acceptable level of morbidity and mortality. The superobese patient, a subcategory of severe obese patients with a high surgical risk has not yet been analyzed as a group. METHODS: A retrospective and prospective cohort study was conducted enrolling 135 patients submitted to Roux-en-Y gastric bypass for treatment of severe obesity at the " Hospital das Clínicas" , Federal University of Pernambuco, Recife, PE, Brazil, between November 1997 and September 2003. The independent variables were possible risk factors of adverse outcomes: age, gender, weight, body mass index, diabetes, hypertension, hypercholesterolemia, sleep apnea, cardiopathy/coronariopathy, pneumopathy or any other co-morbidity. The dependent variables were major complications, minor complications and death. RESULTS: Diabetes (RR = 1.6 and CI = 1.02-2.40) and sleep apnea (RR = 1.8 and CI = 1.18-2.64) were associated to minor complications. Cardiopathy/coronariopathy were associated with major complications (RR = 5.42 and CI = 1.22-2.40) and death (RR = 16.25 and CI = 3.00-87.95). BMI >or=55 kg/m2 was associated with minor complications (RR = 1.58 and CI = 1.04-2.40), major complications (RR = 3.17 and CI = 1.03-9.80) and death (P = 0.007). After logistic regression, the body mass index >55 kg/m2 remained as a strong risk factor of death (OR = 3.6 and CI = 1.05-12.32). CONCLUSIONS: The body mass index >or=55 kg/m2 was the main risk factor for severe complications and death. Other risk factors affecting the outcome were diabetes, obstructive sleep apnea and cardiopathy/coronariopathy.  相似文献   
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