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61.
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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Teas of Bidens pilosa and Mikania glomerata are popularly consumed to medicinal ends. The capacity to induce DNA damages and mutagenic effects of these teas were evaluated, in vitro, on HTC cells, with comet assay and micronucleus test. The teas tested at various doses were prepared differently: infusion of Mikania glomerata (IM) and Bidens pilosa (IB), macerate of Mikania glomerata in 80% ethanol (MM80) and decoction of Bidens pilosa (DB). In IM and MM80, the quantity of coumarin was determined by high-performance liquid chromatography (HPLC) with UV detection. Methylmethanesulfonate was utilized as positive control, phosphate-buffered saline as negative control, 80% ethanol as solvent control and 2-aminoanthracene as drug metabolism control. The comet assay demonstrated genotoxic effects for both plants. The genotoxic potential of IB was upper than DB, showing dose-response. In the MN test, excepting IM 40 microL/mL, all treatments was not mutagenic. The effects did not show direct relation with cumarin quantity present in IM and MM80. The results demonstrated DNA damages at the highest concentrations of alcoholic macerate (10 and 20 microL/mL) and infusion of Mikania glomerata (20 and 40 microL/mL) and of Bidens pilosa infusion (40 microL/mL). Thus, both dose and preparation-form suggest caution in the phytotherapeutic use of these plants.  相似文献   
65.
The purpose of this study is to determine the effectiveness of fetal fibronectin (FFN) compared to assessment of cervical dilation (CD) in clinical management of women with symptomatic preterm labor (PTL). Pregnant women presenting to Thomas Jefferson University Hospital between May 1, 2001 and November 30, 2002 with symptomatic PTL underwent FFN sampling and had a complete clinical evaluation including a pelvic bimanual examination. Inclusion criteria were singleton pregnancy, gestational age (GA) between 24 (0) and 33 (6) weeks, CD < 3 cm, and intact amniotic membranes. FFN samples were sent out and results were available within 4-12 hours. Clinical management including tocolysis, antenatal steroids, and hospitalization was determined based on digital CD assessment and FFN status. A dilated cervix was defined as CD > 1 cm. Ninety-three patients were included. Spontaneous preterm delivery (SPTD) at < 37 weeks occurred in 20 of 93 (21.5%) patients. Medical therapy use was significantly higher in patients with dilated cervix than in those with a closed cervix (all P values < 0.05). Tocolysis and steroid use in FFN-negative patients and FFN-positive patients were not significantly different. Furthermore, tocolytic use was higher in FFN-negative patients than in women with positive FFN (50% versus 42.1%; P = 0.53). Use of antenatal steroids was similar in patients with CD >/= 1 cm and a positive FFN (54.5% versus 47.4%; P = 0.92). Compared with FFN-negative patients, women with closed cervix were less likely to undergo interventions. In symptomatic PTL patients, CD determined clinical management more than FFN status. Overall, the use of FFN was not effective in decreasing "unnecessary" clinical interventions.  相似文献   
66.
STUDY OBJECTIVE: To determine the presence of impaired gonadal function in adolescent patients submitted to chemotherapy during childhood or during the pubertal period. DESIGN: A case series study of 28 patients aged 12 to 19 years with menarche at least 2 years before the study. SETTING: Tertiary care public hospital. PARTICIPANTS: Group I: 14 adolescents previously submitted to chemotherapy during the prepubertal or peripubertal period and with remission of oncologic disease for at least 2 years; Group II: 14 normal adolescents with no previous oncologic disease and with regular menstrual cycles. INTERVENTIONS AND MAIN OUTCOME MEASURES: Pubertal development, menstrual cycles and serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined during the early follicular phase. RESULTS: There were no differences between the two groups in terms of age at appearance of secondary sexual characteristics or age at menarche. Menstrual irregularity was detected in 7 of the 14 patients in Group I, all 8 of whom presented oligomenorrhea. There were no differences in LH levels between the two groups (P = 0.55), although mean FSH levels were higher in Group I than in Group II (6.71 +/- 2.99 mIU/ml vs. 3.83 +/- 2.01 mIU/ml, P = 0.01). CONCLUSION: Although girls submitted to chemotherapy during the prepubertal or peripubertal period presented normal sexual development, the incidence of oligomenorrhea was higher than expected for their age, and FSH levels, although within normal limits, were higher than those seen in normally cycling girls.  相似文献   
67.
Ohne ZusammenfassungZ. Krebsforschg28, 374 (1929).  相似文献   
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BackgroundNetwork analysis has been used to explore the interplay between psychopathology and functioning in psychosis, but no study has used dedicated statistical techniques to focus on the bridge symptoms connecting these domains. The current study aims to estimate the network of depressive, negative, and positive symptoms, general psychopathology, and real-world functioning in people with first-episode schizophrenia or schizophreniform disorder, focusing on bridge nodes.MethodsBaseline data from the OPTiMiSE trial were analyzed. The sample included 446 participants (age 40.0 ± 10.9 years, 70% males). The network was estimated with a Gaussian graphical model, using scores on individual items of the positive and negative syndrome scale (PANSS), the Calgary depression scale for schizophrenia, and the personal and social performance scale. Stability, strength centrality, expected influence (EI), predictability, and bridge centrality statistics were computed. The top 20% scoring nodes on bridge strength were selected as bridge nodes.ResultsNodes from different rating scales assessing similar psychopathological and functioning constructs tended to cluster together in the estimated network. The most central nodes (EI) were Delusions, Emotional Withdrawal, Depression, and Depressed Mood. Bridge nodes included Depression, Conceptual Disorganization, Active Social Avoidance, Delusions, Stereotyped Thinking, Poor Impulse Control, Guilty Feelings, Unusual Thought Content, and Hostility. Most of the bridge nodes belonged to the general psychopathology subscale of the PANSS. Depression (G6) was the bridge node with the highest value.ConclusionsThe current study provides novel insights for understanding the complex phenotype of psychotic disorders and the mechanisms underlying the development and maintenance of comorbidity and functional impairment after psychosis onset.  相似文献   
69.
MLH1 promoter hypermethylation has been described as the primary mechanism for high-frequency microsatellite instability (MSI-H) in sporadic colorectal cancers (CRCs). The underlying molecular mechanism for microsatellite instability (MSI) in synchronous and metachronous CRCs is not well described. A total of 33 metachronous CRC patients and 77 synchronous CRC patients were identified from 2884 consecutive patients undergoing cancer surgery in an academic center. Evaluable tumors were tested for MSI, immunohistochemistry for MLH1 and MSH2 protein expression, and hypermethylation of the MLH1 promoter. MSI-H tumors were found in 12 (36%) metachronous CRC patients and 29 (38%) synchronous CRC patients. MSI-H metachronous CRC patients were younger at index cancer diagnosis (64 vs. 76 years, P = 0.01) and more often were diagnosed before 50 years of age (4 of 12 vs. 0 of 29, P = 0.005). Loss of MLH1 expression associated with promoter hypermethylation was common in all patients, although more common in MSI-H synchronous patients (50% metachronous vs. 83% synchronous, P = 0.03). Overall, MLH1 promoter hypermethylation was seen in 7 of 17 (41%) metachronous and 44 of 54 (81%) synchronous MSI-H CRCs tested (P = 0.004). Although MSI occurred with equal frequency among patients with synchronous and metachronous CRCs, the underlying mechanism for MSI was different. Observed differences in MLH1 promoter hypermethylation and patient characteristics suggest most MSI-H synchronous CRCs in our population were sporadic in origin. In contrast, more MSI-H metachronous CRCs were associated with patient and tumor characteristics suggestive of underlying hereditary nonpolyposis CRC. Presented as a poster at Digestive Disease Week 2001, Atlanta, Georgia, May 20–23, 2001.  相似文献   
70.

Introduction

Invasive respiratory support is a cornerstone of Critical Care Medicine, however, protocols for withdrawal of mechanical ventilation are still far from perfect. Failure to extubation occurs in up to 20% of patients, despite a successful spontaneous breathing trial (SBT).

Methods

We prospectively included ventilated patients admitted to medical and surgical intensive care unit in a university hospital in northern Mexico. At the end of a successful SBT, we measured diaphragmatic shortening fraction (DSF) by the formula: diaphragmatic thickness at the end of inspiration – diaphragmatic thickness at the end of expiration/diaphragmatic thickness at the end of expiration × 100, and the presence of B-lines in five regions of the right and left lung. The primary objective was to determine whether analysis of DSF combined with pulmonary ultrasound improves prediction of extubation failure.

Results

Eighty-two patients were included, 24 (29.2%) failed to extubation. At univariate analysis, DSF (Youden's J: >30% [sensibility and specificity 62 and 50%, respectively]) and number of B-lines regions (Youden's J: >1 zone [sensibility and specificity 66 and 92%, respectively]) were significant related to extubation failure (area under the curve 0.66 [0.52–0.80] and 0.81 [0.70–0.93], respectively). At the binomial logistic regression, only the number of B-lines regions remains significantly related to extubation failure (OR 5.91 [2.33–14.98], P < .001).

Conclusion

In patients with a successfully SBT, the absence of B-lines significantly decreases the probability of extubation failure. Diaphragmatic shortening fraction analysis does not add predictive power over the use of pulmonary ultrasound.  相似文献   
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