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31.

Objectives

Children with Bipolar Mood Disorder (BMD) and those with Attention Deficit Hyperactivity Disorder (ADHD) share many clinical signs and symptoms; therefore, achieving an accurate diagnosis is still a challenge, especially in the first interview session. The main focus of this paper is to quantitatively classify the ADHD and BMD patients using their Visual Evoke Potential (VEP) features elicited from their Electroencephalogram (EEG) signals.

Methods and materials

In this study, 36 subjects were participated including 12 healthy ones, 12 patients with ADHD and 12 ones with BMD. The age of ADHD patients was 16.92 ± 6.29 and for the BMD ones was 17.85 ± 3.68. Their scalp EEG signals in the presence of visual stimulus were recorded using 22 silver electrodes located according to the 10–20 international recording protocol. To extract their VEP, first a preprocessing step was executed to remove the power line and movement artifacts. Afterward, the wavelet denoising and synchronous averaging were applied to the preprocessed trials in order to elicit the P100 component. To obtain interpretable features from the evoked patterns, amplitude and latency were extracted and applied to the 1-Nearest Neighbor (1NN) classifier due to the locally scattered distribution of the VEP features.

Results

The evaluation was performed according to leave-one(subject)-out method and the experimental results were led to 92.85% classification accuracy which is a fairly promising achievement to distinguish the BMD, ADHD, and healthy subjects from each other.

Conclusion

From the physiological point of view, this result point out to the existence of significant difference in the neural activities of their visual system in the ADHD, BMD, and healthy subjects in response to a periodic optical stimulus.  相似文献   
32.

Aims

To evaluate the association between total dietary fiber and its types and sources with the risk of MetS.

Methods

This population-based cross-sectional study was conducted on a representative sample of 2 457 adults (1 327 male and 1 130 female), aged 19-84 years. Dietary intake was assessed using a validated semiquantitative food-frequency questionnaire. Anthropometrics, blood pressure, and fasting blood glucose and lipids were measured according to standard protocols. The MetS was defined according to definition by Adult Treatment Panel III.

Results

Multivariate-adjusted odds ratio of MetS between highest and lowest quartiles was 0.53 (95% CI: 0.39-0.74; P for trend <0.05) for total dietary fiber, 0.60 (0.43-0.84; P for trend <0.05) for soluble fiber, and 0.51 (0.35-0.72; P for trend <0.05) for insoluble fiber. Among sources of dietary fiber, fruit fiber (OR: 0.51; 95% CI: 0.37-0.72), cereal fiber (0.74; 0.57-0.97), and legume fiber (0.73; 0.53-0.99) were inversely associated with the risk of MetS, after adjustment for confounding factors. Intake of vegetable fiber and nut fiber were unrelated to the risk of MetS.

Conclusions

Total dietary fiber, soluble- and insoluble fiber, fruit fiber, cereal fiber and legume fiber were associated with a protective effect for the presence of MetS among this Tehranian population.  相似文献   
33.

Aim

Metabolically Healthy Obese (MHO) is called to obese people that their insulin sensitivity, lipid profiles and inflammatory profiles are favorable, and there are no signs of hypertension and cardio-metabolic diseases. The metabolically unhealthy obese (MUHO) is the opposite. A Body Shape Index (ABSI) is a marker to identifying abdominal obesity that is derived from weight, height and waist circumference (WC). Several studies have reported ABSI is associated with diabetes, metabolic syndrome, hypertension and higher mortality rate.

Materials and methods

A total of 305 overweight and obese women were included in the current comparative cross-sectional study. Body composition was measured using body composition analyzer. Blood samples were obtained. The usual food intake of evaluated through the use of a semi-quantitative food frequency questionnaire.

Results

The results of this study revealed that there is a significant relationship between ABSI and MHO and MUHO (p?=?0.04) and area under the ROC curve was 0.60. Also there is a significant relationship between BMI, fat mass index (FMI), free fat mass index (FFMI), neck circumference (NC), WC, fat mass (FM) and metabolic healthy status (MHS). The largest area under the ROC curve belonged to NC, WC, FM and BMI (0.66).

Conclusion

The findings of this study suggest that there is a significant relationship between ABSI, BMI, FMI, FFMI, NC, WC, FM and MHS. The largest area under the ROC curve was related to the NC, WC, FM and BMI not ABSI, that means NC, WC, FM and BMI have maximum sensitivity and specificity.  相似文献   
34.

Research question

Telomeres are non-coding, repetitive DNA sequences (TTAGGG repeats) that play an important role in maintaining genome integrity. Unlike in somatic cells, telomere length in spermatozoa increases with male age and is considered as a molecular marker of sperm quality. The aetiology of failed fertilization following intracytoplasmic sperm injection (ICSI) is multifactorial; perhaps one of the reasons for this failure in these individuals is shortened sperm telomere length. This study therefore aimed to assess sperm telomere length in addition to DNA damage, lipid peroxidation and protamine deficiency in infertile men with previously failed/low fertilization post-ICSI.

Design

Semen samples were obtained from infertile men with previous failed/low fertilization rates (n?=?10). Chromatin integrity (chromomycin A3 staining and TUNEL assay), lipid peroxidation (BODIPY probe) and telomere length (real-time PCR) for semen samples from these men were compared with samples obtained from fertile individuals (n = 10).

Results

The results showed significantly higher mean values for sperm DNA damage, lipid peroxidation and reduced telomere length in spermatozoa of infertile men with previous failed/low fertilization compared with fertile individuals (P < 0.05).

Conclusions

Failed/low fertilization rates could be related to oxidative stress resulting in short telomere length, and also increased sperm chromatin damage and lipid peroxidation. From literature sources, shortened telomere length may lead to detachment of chromosomes from the nuclear membrane, the consequences of which are defects in the process of spermatogenesis, pronuclei formation, and delayed or arrested cell cycle post-ICSI.  相似文献   
35.
36.
37.
Modification of various properties of graphene oxide (GO) films on SiO2/Si substrate under KrF laser radiation was extensively studied. X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and the electrical resistance measurements were employed to correlate the effects of laser irradiation on structural, chemical and electrical properties of GO films under different laser fluences. Raman spectroscopy shows reduced graphene oxide patterns with increased I2D/IG ratios in irradiated samples. X-ray photoelectron spectroscopy shows a high ratio of carbon to oxygen atoms in the reduced graphene oxide (rGO) films compared to the pristine GO films. X-ray diffraction patterns display a significant drop in the diffraction peak intensity after laser irradiation. Finally, the electrical resistance of irradiated GO films reduced by about four orders of magnitudes compared to the unirradiated GO films. Simultaneously, reduction and patterning of GO films display promising fabrication technique that can be useful for many graphene-based devices.

Modification of various properties of graphene oxide (GO) films on SiO2/Si substrate under KrF laser radiation was extensively studied.  相似文献   
38.

Objective

To assess the effects of anxiety on pregnancy rate after in vitro fertilization (IVF).

Study design

This was a prospective study of 180 infertile women who were referred for IVF treatment to two selected infertility treatment centers in Tehran. They were recruited at the last visit before the procedure by quota sampling and their anxiety was assessed using the State and Trait Anxiety Inventory, following which they were categorized, based on their anxiety scores, to high and low anxiety groups. A positive pregnancy test was considered as the criterion of success of treatment. Data were analyzed using SPSS 17. Pregnancy rates in the low and high anxiety groups were compared using the Chi square test.

Results

Pregnancy rates in the groups with high and low levels of state anxiety were not significantly different (11.1 vs. 10.1 percent; X2, p > 0.05); neither were these rates significantly different in groups with high and low levels of trait anxiety (14.5 vs. 9 percent; X2, P > 0.05).

Conclusion

High or low levels of state or trait anxiety have no effect on the pregnancy rate after IVF treatment. Counseling is necessary, however, to decrease anxiety in infertile women to improve their quality of life.  相似文献   
39.

Ethnopharmacological relevance

Medicinal plants are an important element of medical system. These resources are usually regarded as part of cultural traditional knowledge. We present for the first time the results of an ethnobotanical survey in Kohghiluyeh va Boyer Ahmad province of Iran, conducted between 2008 and 2010. This information could be the basis of an evidence based investigation to discover new drugs.

Materials and methods

Ethnobotanical data were analyzed by use-reports in addition important indices like relative frequency of citation (RFC) and cultural importance index (CI) were calculated. Totally 23 informants were interviewed.

Results

Our study reports 138 traditionally used plant species, belonging to 52 plant families from this province. Asteraceae and Lamiaceae are the dominant locally used families. The highest number of species and application were reported for digestive system disorder, metabolic disorder and respiratory system, respectively. The part of the plant most frequently used was the aerial part (31.9%), leaves (14.8%) and fruits (11.7%). The plants are used both for medicinal and non-medicinal purposes. Daphne mucronata Royle. and Teucrium polium L. have the largest value of relative frequency of citation and cultural importance index, respectively.

Conclusion

Kohghiluyeh va Boyer Ahmad has good ethnobotanical potential for medicinal plants. This study is the first contribution to the ethnobotany of this region. We have gathered from this province some considerable knowledge about local medicinal plants for treating common health problem that is ready to be further investigated in the laboratory.  相似文献   
40.
The current study aimed to enhance the efficacy of peripheral nerve regeneration using a hydroxyapatite nanoparticle-containing collagen type I hydrogel. A solution of type I collagen, extracted from the rat tails, was incorporated with hydroxyapatite nanoparticles (with the average diameter of ~212 nm) and crosslinked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to prepare the hydrogel. The Schwann cell cultivation on the prepared hydrogel demonstrated a significantly higher cell proliferation than the tissue culture plate, as positive control, after 48 h (n = 3, P < 0.005) and 72 h (n = 3, P < 0.01). For in vivo evaluation, the prepared hydrogel was administrated on the sciatic nerve crush injury in Wistar rats. Four groups were studied: negative control (with injury but without interventions), positive control (without injury), collagen hydrogel and hydroxyapatite nanoparticle-containing collagen hydrogel. After 12 weeks, the administration of hydroxyapatite nanoparticle-containing collagen significantly (n = 4, P < 0.005) enhanced the functional behavior of the rats compared with the collagen hydrogel and negative control groups as evidenced by the sciatic functional index, hot plate latency and compound muscle action potential amplitude measurements. The overall results demonstrated the applicability of the produced hydrogel for the regeneration of peripheral nerve injuries.  相似文献   
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