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The choice of casarean deliveries by mothers is highly influenced by inadequate knowldge and negative attitudes towards vaginal birth. In this semi-experimental study, we compared knowledge, attitude, and decision making about modes of delivery between nulliparous pregnant women who received eight sessions of group consultation and those who took routine prenatal education. Contrary to the control group, the improvement of knowledge and attitudes were significant in the consultation group (p < 0.001), as well as mothers' decisions for vaginal birth (p = 0.03). Group consultation is an appropriate approach to improving knowledge, attitudes, and tendencies of mothers toward natural birth.  相似文献   
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Purpose

Functional magnetic resonance imaging (fMRI) in resting state can be used to evaluate the functional organization of the human brain in the absence of any task or stimulus. The functional connectivity (FC) has non-stationary nature and consented to be varying over time. By considering the dynamic characteristics of the FC and using graph theoretical analysis and a machine learning approach, we aim to identify the laterality in cases of temporal lobe epilepsy (TLE).

Methods

Six global graph measures are extracted from static and dynamic functional connectivity matrices using fMRI data of 35 unilateral TLE subjects. Alterations in the time trend of the graph measures are quantified. The random forest (RF) method is used for the determination of feature importance and selection of dynamic graph features including mean, variance, skewness, kurtosis, and Shannon entropy. The selected features are used in the support vector machine (SVM) classifier to identify the left and right epileptogenic sides in patients with TLE.

Results

Our results for the performance of SVM demonstrate that the utility of dynamic features improves the classification outcome in terms of accuracy (88.5% for dynamic features compared with 82% for static features). Selecting the best dynamic features also elevates the accuracy to 91.5%.

Conclusion

Accounting for the non-stationary characteristics of functional connectivity, dynamic connectivity analysis of graph measures along with machine learning approach can identify the temporal trend of some specific network features. These network features may be used as potential imaging markers in determining the epileptogenic hemisphere in patients with TLE.

  相似文献   
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The structure, adsorption characteristics, electronic properties, and charge transfer of SO2 and NO2 molecules on metal-doped gallium nitride nanosheets (M-GaNNSs; M = Ti and Cr) were scrutinized at the Grimme-corrected PBE/double numerical plus polarization (DNP) level of theory. Two types, MGa-GaNNSs and MN-GaNNSs, of doped nanostructures were found. The MGa sites are more stable than the MN sites. The results showed that adsorption of SO2 and NO2 molecules on TiGa,N-GaNNSs is energetically more favorable than the corresponding CrGa,N-GaNNSs. The stability order of complexes is energetically predicted to be as NO2–TiGa-GaNNS > NO2–TiN-GaNNS > SO2–TiGa-GaNNS > NO2–CrN-GaNNS > SO2–TiN-GaNNS > NO2–CrGa-GaNNS > SO2–CrN-GaNNS > SO2–CrGa-GaNNS. The electron population analysis shows that charge is transferred from MGa,N-GaNNSs to the adsorbed gases. The TiGa-GaNNS is more sensitive than the other doped nanostructures to NO2 and SO2 gases. It is estimated that the sensitivity of TiGa-GaNNS to NO2 gas is more than to SO2 gas.

The influences of transition metals (Cr and Ti) doping on the adsorption behavior of SO2 and NO2 gases on the metal doped Gallium Nitride Nanosheet (GaNNS) were explored at Grimme-corrected PBE/double numerical plus polarization (DNP) level of theory.  相似文献   
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Clinical Oral Investigations - The aim of this study was to assess in a multi-modular manner the bone healing 1&nbsp;year post root-end surgery (RES) with leukocyte- and platelet-rich fibrin...  相似文献   
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Background

Based on previous studies, Iran is located in a low risk area in terms of multiple sclerosis (MS). The objective of this study was to determine and compare the incidence, prevalence and demographic characteristics of MS in two ethnic groups of Persian and Arab over the period spanning 2009 in the Khuzestan province, in the Southwest of Iran.

Methods

A cross-sectional case register study was conducted between January and August 2009. All cases in the region whom were referred to the MS society in the city of Ahwaz were participants in the study. The population data from the Iranian Bureau of Statistics were used to calculate the population at risk based on the 1996 and 2006 census data.

Results

A total of 696 patients were identified according to the McDonald criteria during the last 12 years of which 569 patients were Persian. In 2009 the total prevalence and incidence rates of MS were 16.28 and 2.20 per 100,000 individuals. Based on these values, the female to male ratios were 3.11. The Persians manifested more sensory signs and symptoms (40.2%) but motor deficits (19.1%) and cerebellar findings (18.2%) were seen as being more manifest in Arab individuals. The main difference was observed in the progressive types of MS in which 24.7% of the Arab patients showed progressive type symptoms as compared to 15.9% of the cases in the Persian population.

Conclusion

According to this study the authors conclude that the prevalence and incidence of MS were higher in Persians; however progressive forms of MS with motor and cerebellar signs are more frequent in the Arab ethnic group.  相似文献   
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Coumarins and their derivatives are receiving increasing attention due to numerous biochemical and pharmacological applications. In this study, a series of novel coumarin–1,2,3-triazole-acetamide hybrids was tested against some metabolic enzymes including α-glycosidase (α-Gly), α-amylase (α-Amy), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), human carbonic anhydrase I (hCA I), and hCA II. The new coumarin–1,2,3-triazole-acetamide hybrids showed Ki values in the range of 483.50–1,243.04 nM against hCA I, 508.55–1,284.36 nM against hCA II, 24.85–132.85 nM against AChE, 27.17–1,104.36 nM against BChE, 590.42–1,104.36 nM against α-Gly, and 55.38–128.63 nM against α-Amy. The novel coumarin–1,2,3-triazole-acetamide hybrids had effective inhibition profiles against all tested metabolic enzymes. Also, due to the enzyme inhibitory effects of the new hybrids, they are potential drug candidates to treat diseases such as epilepsy, glaucoma, type-2 diabetes mellitus (T2DM), Alzheimer's disease (AD), and leukemia. Additionally, these inhibition effects were compared with standard enzyme inhibitors like acetazolamide (for hCA I and II), tacrine (for AChE and BChE), and acarbose (for α-Gly and α-Amy). Also, those coumarin–1,2,3-triazole-acetamide hybrids with the best inhibition score were docked into the active site of the indicated metabolic enzymes.  相似文献   
9.

Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
10.
Tensional homeostasis and the malignant phenotype   总被引:25,自引:0,他引:25  
Tumors are stiffer than normal tissue, and tumors have altered integrins. Because integrins are mechanotransducers that regulate cell fate, we asked whether tissue stiffness could promote malignant behavior by modulating integrins. We found that tumors are rigid because they have a stiff stroma and elevated Rho-dependent cytoskeletal tension that drives focal adhesions, disrupts adherens junctions, perturbs tissue polarity, enhances growth, and hinders lumen formation. Matrix stiffness perturbs epithelial morphogenesis by clustering integrins to enhance ERK activation and increase ROCK-generated contractility and focal adhesions. Contractile, EGF-transformed epithelia with elevated ERK and Rho activity could be phenotypically reverted to tissues lacking focal adhesions if Rho-generated contractility or ERK activity was decreased. Thus, ERK and Rho constitute part of an integrated mechanoregulatory circuit linking matrix stiffness to cytoskeletal tension through integrins to regulate tissue phenotype.  相似文献   
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