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61.
62.
Auditory cortices are interconnected to each other by fibers passing through the corpus callosum (CC). In totally deaf persons no auditory impulses are conveyed to the auditory cortices, hence the auditory pathways become nonfunctional. It was reported that there has been cross-modal plasticity between auditory, visual, and somatosensory cortices. In this study, our aim was to make a comparison in the CC morphometry in hearing subjects and in a selected group in which the auditory system was deprived before the age of 2. 18 deaf and 18 hearing male, handedness matched volunteers, ages varying between 28 and 56 years old were examined. Audiometrical tests were applied to both groups and then T1-weighted midsagittal MR images were obtained. Certain dimensions and areas were measured on these images. There were no statistically significant difference between deaf and hearing subjects, either when dimensions and areas were analyzed by multivariate analysis of variance or when areas were analyzed by univariate analysis of variance. Absence of any significant morphometric difference in the CC of deaf subjects could be thought as an evidence of reflection of functional cortical plasticity.  相似文献   
63.

Background  

In investigations of the human motor system, two approaches are generally employed toward the identification of common modulating drives from motor unit recordings. One is a frequency domain method and uses the coherence function to determine the degree of linear correlation between each frequency component of the signals. The other is a time domain method that has been developed to determine the strength of low frequency common modulations between motor unit spike trains, often referred to in the literature as 'common drive'.  相似文献   
64.
65.
We investigated the development of cartilage canals to clarify their function in the process of bone formation. Cartilage canals are tubes containing vessels that are found in the hyaline cartilage prior to the formation of a secondary ossification centre (SOC). Their exact role is still controversial and it is unclear whether they contribute to endochondral bone formation when an SOC appears. We examined the cartilage canals of the chicken femur in different developmental stages (E20, D2, 5, 7, 8, 10 and 13). To obtain a detailed picture of the cellular and molecular events within and around the canals the femur was investigated by means of three-dimensional reconstruction, light microscopy, electron microscopy, histochemistry and immunohistochemistry [vascular endothelial growth factor (VEGF), type I and II collagen]. An SOC was visible for the first time on the last embryonic day (E20). Cartilage canals were an extension of the vascularized perichondrium and its mesenchymal stem cell layers into the hyaline cartilage. The canals formed a complex network within the epiphysis and some of them penetrated into the SOC were they ended blind. The growth of the canals into the SOC was promoted by VEGF. As the development progressed the SOC increased in size and adjacent canals were incorporated into it. The canals contained chondroclasts, which opened the lacunae of hypertrophic chondrocytes, and this was followed by invasion of mesenchymal cells into the empty lacunae and formation of an osteoid layer. In older stages this layer mineralized and increased in thickness by addition of further cells. Outside the SOC cartilage canals are surrounded by osteoid, which is formed by the process of perichondral bone formation. We conclude that cartilage canals contribute to both perichondral and endochondral bone formation and that osteoblasts have the same origin in both processes.  相似文献   
66.
Occupational exposure to wood dust is associated with the occurrence of nasal cancer. In this study, we investigated micronuclei and nuclear changes (NCs: binucleates, karyorrhexis, karyolysis, and the "broken egg" effect) in exfoliated buccal cells of 20 workers exposed to wood dust and 20 age- and sex-matched controls. Micronucleus frequency and the frequency of each of the NCs were significantly higher for wood workers than controls (P < 0.01). Cigarette smoking was associated with increased frequencies of micronuclei and NCs in the buccal mucosa epithelium cells of both the control and exposed groups. Our findings indicate that buccal cells of wood workers display increased levels of genotoxicity and toxicity, and that these biomarker responses may be related to the increased cancer risk among wood workers.  相似文献   
67.
Aims: To evaluate the temperament and quality of life (QoL) of patients with PCOS.

Materials and methods: Fifty-three adult patients with PCOS and 38 healthy controls were enrolled in the study. Demographic characteristics including age, education and body mass index (BMI) were recorded. Affective temperaments were assessed by the temperament evaluation of Memphis, Pisa, Paris and San Diego-autoquestionnaire version (TEMPS-A) scale. The general health-related quality of life (HRQoL) instrument used in this study was short Form 36. Hospital anxiety and depression scale (HADS) were also performed.

Results: The patients with PCOS had significantly higher rates of depressive, anxious and hyperthymic scores compared to controls. The PCOS patients had significantly lower mean SF-36 health summary scores.

Conclusions: TEMPS-A seems to be an easy and reliable test to evaluate temperament in PCOS patients.  相似文献   

68.
Objective: The aim of the study was to evaluate the neurodevelopment outcomes of very low birth weight (VLBW) preterm infants supplemented with oral probiotics for the prevention of necrotizing enterocolitis (NEC).

Methods: A prospective follow-up study was performed in a cohort of VLBW preterm infants enrolled in a single center randomized controlled clinical trial to evaluate the efficacy of oral probiotics for the prevention of NEC. Cognitive and neuromotor developments were assessed by using the Bayley scales of infant development II. Sensory and neurological performance was evaluated by standard techniques. The primary outcome was neurodevelopmental impairment at 18–24 months’ corrected age.

Results: A total of 400 infants completed the trial protocol. Of the 370 infants eligible for follow-up, 249 infants (124 in the probiotics group and 125 in the control group) were evaluated. There was no significant difference in any of the neurodevelopmental and sensory outcomes between the two groups.

Conclusion: Oral probiotic given to VLBW infants to reduce the incidense and severity of NEC started with the first feed did not affect neuromotor, neurosensory and cognitive outcomes at 18–24 months’ corrected age.  相似文献   

69.
Latent autoimmune diabetes mellitus in adults (LADA) is characterized by clinical presentation as type 2 diabetes mellitus after 25 years of age, initial control achieved with oral hypoglycemic agents for at least 6 months, presence of autoantibodies and some immunogenetic features of type 1 diabetes mellitus. An 8.3 year-old girl was referred to our pediatric endocrinology department because of incidental glucosuria. She did not complain of polyuria, polydipsia, or weight loss. Her body mass index (BMI) was at the 80th percentile. Fasting glucose was 126 mg/dl, and OGTT glucose level at 120 min was 307 mg/dl. Although C-peptide levels were normal, her first phase insulin response (FIR) was lower than the 1st percentile. Anti-insulin antibody (AIA), islet cell antibody (ICA), and anti-glutamic acid decarboxylase (antiGAD) were negative. According to the clinical and laboratory findings, she was diagnosed as having type 2 diabetes mellitus. She was started with oral anti-diabetic treatment for a period of 1 year. Insulin had to be initiated for worsening of HbA1c levels. In the fourth year of follow-up, she was admitted to our hospital with diabetic ketoacidosis although she was on an intensive insulin regimen. At this time, C-peptide levels were low, antiGAD and AIA were positive with HLA DR3/DQ2 haplotype. In addition, her thyroid peroxidase antibody and endomysium antibody were found to be high at follow-up. Small intestinal biopsy revealed celiac disease. This patient may represent the first case of latent autoimmune diabetes mellitus in children (LADC) with autoimmune thyroiditis and celiac disease.  相似文献   
70.

Purpose

The present study aimed to evaluate whether combining the magnetic-activated cell sorting (MACS) with density-gradient (DG) or swim-up (SU) sperm separation techniques can improve sperm selection to obtain higher quality spermatozoa.

Methods

Two commonly used sperm selection techniques, SU and DG, were compared to MACS combined with either SU or DG. Spermatozoa obtained from normozoospermic (n?=?10) and oligozoospermic (n?=?10) cases were grouped as SU, DG, SU+MACS, and DG+MACS followed by the analysis of sperm morphology, motility, DNA integrity, and the levels of Izumo-1 and PLCZ proteins.

Results

Although spermatozoa obtained by SU or DG when combined with MACS have improved aspects when compared to SU or DG alone, results did not reach a statistically significant level. Moreover, separation with MACS caused a significant loss in the numbers of total and rapid progressive spermatozoa.

Conclusions

Considering the cost/benefit ratio, MACS application together with traditional techniques may only be preferred in certain cases having higher concentrations of spermatozoa, but it does not seem to be an ideal and practical sperm selection technique for routine use.
  相似文献   
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