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101.

Background:

Retinopathy of prematurity (ROP) is the main cause of visual impairment in preterm newborn infants.

Objective:

This study was conducted to determine whether insulin-like growth factor binding protein -3 (IGFBP-3) is associated with proliferative ROP and has a role in pathogenesis of the disease in premature infants.

Materials and Methods:

A total of 71 preterm infants born at or before 32 weeks of gestation participated in this study. Studied patients consisted of 41 neonates without vaso-proliferative findings of ROP as the control group and 30 preterm infants with evidence of severe ROP in follow up eye examination as the case group. Blood samples obtained from these infants 6-8 weeks after birth and blood levels of IGFBP-3 were measured using enzyme-linked immunosorbent assay (ELISA).

Results:

The mean gestation age and birth weight of the studied patients were 28.2±1.6 weeks and 1120.7±197 gram in the case group and 28.4±1.6 weeks and 1189.4±454 gram in the control group (P=0.25 and P=0.44 respectively). The infants in the case group had significantly lower Apgar score at first and 5 min after birth. Insulin-like growth factor binding protein -3 (IGFBP-3) was significantly lower in the patients with proliferative ROP than the patients without ROP [592.5±472.9 vs. 995.5±422.2 ng/ml (P=0.009)]. Using a cut-off point 770.45 ng/ml for the plasma IGFBP-3, we obtained a sensitivity of 65.9% and a specificity of 66.7% in the preterm infants with vasoproliferative ROP.

Conclusion:

Our data demonstrated that the blood levels IGFBP-3 was significantly lower in the patients with ROP and it is suspected that IGFBP-3 deficiency in the premature infants may have a pathogenetic role in proliferative ROP.  相似文献   
102.
Although esophageal liposarcoma is an extremely rare tumor, liposarcoma is the most common soft tissue sarcoma in adults. Liposarcoma is currently classified into the types of well-differentiated, myxoid, round cell, pleomorphic and dedifferentiated liposarcoma. Up to now only a few cases of esophagus liposarcoma have been described in the world literature. We describe a myxoid type liposarcoma of the esophagus in a 68 year old man presented with hoarseness and intermittent dysphagea to solid food. He had a huge mass in his mouth which was mobile with gag reflex. A barium swallow, esophageal manometery and CT scan of the esophagus have not clearly revealed the mass. After endoscopic surgical resection of the tumor the histological examination revealed a myxoid liposarcoma. Both the presenting signs and symptoms and the histology type are rare for such tumor. This case demonstrate a rare differential diagnosis of intermittent dysphagia as early diagnosis is so important in those tumors and should kept in mind them, although they are quite rare.  相似文献   
103.
Brachytherapy dose distributions are calculated for 15 mm ROPES eye plaque loaded with model Theragenics200 and IR06-103Pd seeds. The effects of stainless steel backing and Acrylic insert on dose distribution along the central axis of the eye plaque and at critical ocular structure are investigated. Monte Carlo simulation was carried out with the Version 5 of the MCNP. The dose at critical ocular structure by considering the eye composition was calculated. Results are compared with the calculated data for COMS eye plaque loaded with Theragenics200 palladium-103 seeds and model 6711 iodine-125 seed. The air kerma strength of the IR06-103Pd seed to deliver 85 Gy in apex of tumor in water medium was calculated to be 4.10 U/seed. Along the central axis of stainless steel plaque loaded with new 103Pd seeds in Acrylic insert, the dose reduction relative to water is 6.9% at 5 mm (apex). Removal of the Acrylic insert from the plaque (replacing with water) did not make significantly difference in dose reduction results (~0.2%). The presence of the stainless steel backing results in dose enhancement near the plaque relative to water. Doses at points of interest are higher for ROPES eye plaque when compared to COMS eye plaque. The dosimetric parameters calculated in this work for the new palladium seed, showed that in dosimetry point of view, the IR06-103Pd seed is suitable for use in brachytherapy. The effect of Acrylic insert on dose distribution is negligible and the main effect on dose reduction is due to the presence of stainless steel plaque backing.  相似文献   
104.
105.
Nasoalveolar cysts are uncommon nonodontogenic and developmental cysts with an uncertain pathogenesis. This cyst has been reported to occur bilaterally in 10–11% of cases. This case report describes a 45-year-old woman in whom the clinicopathologic findings were consistent with bilateral nasoalveolar cysts. The authors report a new, less invasive method for transnasal endoscopic marsupialization of bilateral nasoalveolar cysts. Transnasal endoscopic marsupialization has benefits for the treatment of bilateral and unilateral nasoalveolar cysts.  相似文献   
106.
Aims  To study the feasibility and impact of a comprehensive, integrated, community-based program directed towards reducing modifiable risk factors for cardiovascular disease. In this study, we reported the differences in the impacts of IHHP on physical activity, smoking and nutritional behaviors of a study population based on sex. Subjects and methods  Using multi-stage cluster sampling on people aged ≥19 years of both intervention and reference areas, 12,514 individuals in 2001, 5,891 in 2002, 4,793 in 2003 and 6,097 in 2004 as well as a sample of 3,011 participants from the intervention area in 2005 were enrolled. Women made up 50.8 percent of participants, with similar proportions from 2001 to 2005 and comparable distribution between intervention and reference areas. Eight distinct component interventional projects were designed separately for both sexes to improve modifiable risk factors in the intervention area. The WHO STEPwise risk factor surveillance questionnaires were used to conduct the annual cross-sectional surveys for behavioral changes. Estimates of intervention effect ratio were conducted based on annual changes in the behavioral modifiable risk factors for both men and women. Results  Intervention activities positively affected the total and leisure-time physical activities in men, but not women. Dietary choice of both sexes showed modest degrees of improvement. Smoking status of men improved in the study period (except 2004), while the effect on women was not significant. Conclusions  Further interventions to improve physical activity in women should be regarded as a health priority in Iran. Sex differences should be considered in implementing any health promotion activity. Grant no. HQ/03/873531, WHO Department of Chronic Disease and Health Promotion  相似文献   
107.
Rats were treated chronically with epinephrine (EPI-T; 100 micrograms/kg/hr, s.c.) for 6 days. On day 6 of treatment, the rats were anesthetized and the mesenteric vascular bed was isolated and perfused with Krebs' bicarbonate buffer containing cocaine (10 microM) and corticosterone (40 microM). Stimulus-induced (2 Hz, 120 pulses) overflow of neurotransmitter and its modulation by prejunctional adrenoceptors was studied. After chronic exposure to EPI, 50% of the mesenteric catecholamine stores consisted of EPI with no increase in total catecholamine content as compared to the control group (C). Absolute and fractional overflows of catecholamines upon periarterial nerve stimulation (2 Hz, 1 min) were not significantly different in the two groups. Beta adrenoceptor blockade by propranolol (10(-10) to 10(-6) M) did not alter the overflow of catecholamines. Alpha adrenoceptor blockade by phentolamine (10(-5) M) increased neurotransmitter overflow in both EPI-T and C groups. However, there was no significant difference in total catecholamine overflows between the two groups. Moreover, in the presence of phentolamine, propranolol (10(-6) M) remained without effect on overflow in both groups. These data suggest that EPI-T did not significantly increase the stimulus-induced overflow of catecholamines in the rat mesentery, nor did EPI-T result in prejunctional beta adrenoceptor modulation of neurotransmitter release in the mesenteric vascular bed.  相似文献   
108.
BACKGROUND: The Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma2 (PPARgamma-2) gene has been variably associated with insulin resistance, obesity and type 2 diabetes in several populations. However, this association has not been studied in Iranian subjects and we hypothesized that this variation might be associated with insulin resistance, type 2 diabetes and related metabolic traits in this population. METHODS: The Pro12Ala genotypes were determined by PCR-restriction fragment length polymorphism in 696 unrelated subjects including 412 non-diabetic controls and 284 type 2 diabetic patients. RESULTS: The frequency of the Ala allele was 9.4% and 5.9% in controls and type 2 diabetic subjects, respectively [adjusted odds ratio (OR) 0.457, p=0.005]. The Ala allele did not show a significant effect on anthropometric and biochemical parameters in the type 2 diabetic group, whereas in non-diabetic subjects, carriers of the Ala allele had significantly lower fasting insulin (p=0.007) and homeostasis model assessment of insulin resistance (HOMA-IR) (p=0.009) levels compared to Pro/Pro subjects. Multivariate logistic regression analysis showed that Pro12Ala polymorphism was an independent determinant of type 2 diabetes in this population. CONCLUSIONS: Our results for a sample of Iranian type 2 diabetes cases and controls provide evidence that the Pro/Ala genotype of the PPARgamma-2 gene is associated with insulin sensitivity and may also have protective role against type 2 diabetes.  相似文献   
109.
Plasticity in neuronal responses is necessary for compensation following brain lesions and adaptation to new conditions and motor learning. In a previous study, we showed that compensatory changes in the vestibuloocular reflex (VOR) following unilateral vestibular loss were characterized by dynamic reweighting of inputs from vestibular and extravestibular modalities at the level of single neurons that constitute the first central stage of VOR signal processing. Here, we studied another class of neurons, i.e., the vestibular-only neurons, in the vestibular nuclei that mediate vestibulospinal reflexes and provide information for higher brain areas. We investigated changes in the relative contribution of vestibular, neck proprioceptive, and efference copy signals in the response of these neurons during compensation after contralateral vestibular loss in Macaca mulata monkeys. We show that the time course of recovery of vestibular sensitivity of neurons corresponds with that of lower extremity muscle and tendon reflexes reported in previous studies. More important, we found that information from neck proprioceptors, which did not influence neuronal responses before the lesion, were unmasked after lesion. Such inputs influenced the early stages of the compensation process evidenced by faster and more substantial recovery of the resting discharge in proprioceptive-sensitive neurons. Interestingly, unlike our previous study of VOR interneurons, the improvement in the sensitivity of the two groups of neurons did not show any difference in the early or late stages after lesion. Finally, neuronal responses during active head movements were not different before and after lesion and were attenuated relative to passive movements over the course of recovery, similar to that observed in control conditions. Comparison of compensatory changes observed in the vestibuloocular and vestibulospinal pathways provides evidence for similarities and differences between the two classes of neurons that mediate these pathways at the functional and cellular levels.  相似文献   
110.
There is currently no imaging modality to track the remodeling process, a common feature of a broad spectrum of vasculopathies, in vivo. alphavbeta3 Integrin is up-regulated in proliferating vascular cells. RP748, a novel peptidomimetic tracer, binds specifically to the activated alphavbeta3 conformer and exhibits favorable binding characteristics for in vivo imaging. In a model of injury-induced vascular remodeling in apoE null mice, RP748 localization to the injured carotid arteries parallels vascular cell proliferation, providing an opportunity to image the remodeling process in vivo.  相似文献   
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