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1.
Vitamin D is critical for calcium, phosphate homeostasis and for mineralization of the skeleton, especially during periods of rapid growth. Vitamin D Deficiency leads to rickets (in children) and osteomalacia (in adults). Expression and activation of the vitamin D receptor (VDR) are necessary for the effects of vitamin D, in which several single nucleotide polymorphisms have been identified especially (FokI, BsmI). In this study serum 25 (OH) vitamin D3 levels were estimated by Enzyme Linked Immunosorbent Assay [ELISA], VDR (FokI, BsmI) gene polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay [PCR–RFLP].Serum levels of calcium, phosphorus, alkaline phosphatase and ferritin were determined in 50 Pediatrics beta thalassemia major patients and 60 controls. Patients had significantly lower serum calcium (p < 0.001) lower serum vitamin D3 (p < 0.001) with elevated levels of phosphorus (p < 0.001) and alkaline phosphatase than controls (p = 0.04). Of the patients studied, 60 % had vitamin D deficiency (<20 ng/ml), 20 % had vitamin D insufficiency (21–30 ng/ml) and 20 % had sufficient vitamin D status (>30 ng/ml). Patients harboring mutant (Ff,ff) and wild (BB) genotypes were associated with lower serum calcium (p = 0.08, 0.02) respectively, lower vitamin D3 levels (p < 0.001, 0.01) respectively. They were also suffering from more bony complications although the difference was not statistically significant (p > 0.05). In conclusion, these results suggest that the VDR (FokI, BsmI) gene polymorphisms influence vitamin D status, (Ff,ff), BB genotypes had lower vitamin D levels, so they might influence risk of development of bone diseases in beta thalassemia major.  相似文献   
2.
AIM: To study the effect of topical dorzolamide 2% on macular thickness reduction in diabetic cystoid macular edema (CME). METHODS: This was a prospective, non-randomized, open study including eyes with diabetic macular edema (DME). All eyes received topical dorzolamide 2% three times daily for one month. Changes in best-corrected visual acuity (BCVA), and central macular thickness (CMT) by optical coherence tomography) were evaluated at 1wk, 1, and 3mo post-treatment. RESULTS: Ninety-three eyes (84 patients) were included. Mean±SD (logMAR) BCVA improved significantly from 1.08±0.26 pretreatment to 0.66±0.24 at 1mo and 0.87±0.26 at 3mo post-treatment (P<0.001 both). The mean±SD CMT was significantly reduced from 535.27±97.4 μm at baseline to 357.43±125.8 μm at 1mo and 376.23±114.5 μm at 3mo post-treatment (P<0.001 both). No significant ocular or systemic side effects were recorded. CONCLUSION: Topical dorzolamide 2% results in significant improvement of mean BCVA and reduction of mean CMT at 3mo post-treatment. It can be used as an effective, affordable, and safe therapy for treatment of non-refractory diabetic CME.  相似文献   
3.

Background  

This study was planned to compare the traditional method of laparoscopic cholecystectomy (LC) versus LC using harmonic as regard the safety and efficacy.  相似文献   
4.
A new green (chlorine-free) high energy dense oxidizer (HEDO) 2,2,2-trinitroethyl-formate (TNEF) and its propellant formulation based on the hydroxyl-terminated polybutadiene (HTPB) as a binder was prepared and studied. The new oxidizer TNEF was successfully prepared and characterized by nuclear magnetic resonance (NMR) and FTIR spectrometer. Scanning electron microscopy (SEM) was used to check the crystal morphology of the oxidizer. A high specific impulse (Is = 250.1 s) was obtained from the characteristics calculation of the new oxidizer instead of (Is = 156.9 s) for the commonly used ammonium perchlorate (AP) by using EXPLO5_V6.03 software. The burning behavior and the burning rate were determined by using a high speed camera. TNEF and the propellant formulations were studied by using nonisothermal thermogravimetric analysis (TGA) and the kinetic parameters of the studied samples were determined by using isoconversional (model-free) methods “Kissinger, Ozawa and Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS)”. The results proved that the new oxidizer and its formulation based on HTPB have chlorine-free decomposition products and have higher performance characteristics than the traditional propellants.

Burning behavior of a traditional (AP/HTPB) and new (TNEF/HTPB) propellants.  相似文献   
5.

Background  

Gastro-Esophageal Reflux Disease (GERD) defined as a condition that develops when the reflux of stomach contents causes troublesome symptoms and/or complications. Many drugs are used for the treatment of GERD such as omeprazole (a proton pump inhibitor) which is a widely used antiulcer drug demonstrated to protect against esophageal mucosal injury. Melatonin has been found to protect the gastrointestinal mucosa from oxidative damage caused by reactive oxygen species in different experimental ulcer models. The aim of this study is to evaluate the role of exogenous melatonin in the treatment of reflux disease in humans either alone or in combination with omeprazole therapy.  相似文献   
6.
Studies in both animal models and humans have shown a subset of B cells behaving as immuno-regulatory cells, being a source of inhibitory cytokines such as IL-10 and TGF-β. Our aims were to establish the presence of human B regulatory (Breg) cells and to assess their ability to suppress proliferation of CD4(+) T cells and to mediate T regulatory (Treg) cells' properties. For this purpose, human Breg, CD4(+) T and Treg cells were purified using magnetic microbeads. CFSE-labeled CD4(+) T cells were stimulated and cultured alone or with Breg cells. Their proliferative response was determined 72 hours later based on the CFSE staining. In parallel, Treg cells were cultured alone or with Breg cells in different conditions for 24 hours, and then stained and analyzed for Foxp3 and CTLA-4 expression. We found that, the co-culture of Breg cells (defined as CD25(high) CD27(high) CD86(high) CD1d(high) IL-10(high) TGF-β(high)) with autologous stimulated CD4(+) T cells decreased significantly (in a dose-dependent way) the proliferative capacity of CD4(+) T cells. Furthermore, Foxp3 and CTLA-4 expression in Treg cells were enhanced by non-stimulated and further by ODN-CD40L stimulated Breg cells. The regulatory function of Breg cells on Treg cells was mainly dependent on a direct contact between Breg and Treg cells, but was also TGF-β but not IL-10 dependent. In conclusion, human Breg cells decrease the proliferation of CD4(+) T cells and also enhance the expression of Foxp3 and CTLA-4 in Treg cells by cell-to-cell contact.  相似文献   
7.
[Purpose] To investigate the efficacy of the multi-wave locked system laser therapy on the regeneration of peripheral nerve injuries by evaluating the functional, electrophysiological, and morphological changes of the crushed sciatic nerve in Wistar rats. [Materials and Methods] Sixty male Wistar rats (200–250 g) were randomly assigned to control negative, control positive, or laser groups and subjected to no laser therapy or crushing, to crushing without laser therapy, or crushing followed by multi-wave locked system laser therapy five times/week for four weeks (power=1 W, energy density=10 J/cm2, total energy=100 J), respectively. Functional, electrophysiological, and morphometric analyses were performed before and 7, 15, 21, and 28 days after crushing. The sciatic functional index, compound motor action potential amplitude, motor nerve conduction velocity, and nerve and myelin sheath diameters were measured. [Results] The sciatic functional index value decreased significantly, while the compound motor action potential amplitude, motor nerve conduction velocity, nerve diameter, and myelin sheath diameter increased significantly in the laser group post-treatment compared to the values in the control groups. [Conclusion] Multi-wave locked system laser therapy was effective in accelerating the regeneration of crushed sciatic nerves in Wistar rats.  相似文献   
8.
9.
AIM: To evaluate the effect of prophylactic administration of nepafenac in prevention of macular edema occurring in diabetic patients after phacoemulsification and to investigate the correlation between optical coherence tomography (OCT) foveal thickness and multifocal electroretinogram (MF-ERG) parameters. METHODS: The study included two groups. Group 1 included 50 diabetic patients with senile cataract (50 eyes, 30 females, 20 males, aged 55±7y) received nepafenac 0.1% eye drop. Group 2 included another 50 diabetic patients with senile cataract (50 eyes, 22 female, 28 males, aged 53.8±8y) did not receive nepafenac. All patients were followed up for 3mo postoperatively. OCT and MF-ERG were done preoperative and at 1wk, 1, 2 and 3mo. RESULTS: The mean foveal thickness was statistically significantly lower in Group 1. Five eyes in Group 2 developed clinical cystoid macular oedema (CMO) (10%), and no patients in Group 1 developed central macular thickening more than 50 μm. There were insignificant differences in MF-ERG amplitudes and latencies between the two groups except in the five eyes that developed CMO, there statistically significant reduction of MF-ERG amplitude with increase in foveal thickness. CONCLUSION: Perioperative nepafenac reduces the incidence of CMO following uncomplicated phacoemulsification significantly. Nepafenac has no side effects.  相似文献   
10.
PurposeThis study was designed to evaluate the role of multiparametric magnetic resonance imaging (MRI) for differentiation of parotid gland neoplasms.MethodsProspective study was conducted upon 52 consecutive patients (30 men, 22 women; aged 24–78 years; mean, 51 years) with parotid tumours that underwent multiparametric MRI using combined static MRI, dynamic contrast enhanced (DCE) MRI, and diffusion-weighted imaging (DWI). The static MRI parameter, time signal intensity curves (TIC) derived from DCE-MRI, and apparent diffusion coefficient (ADC) values of parotid tumours were correlated with histopathological findings.ResultsStatic MRI revealed a significant difference between both benign and malignant lesions in regards to margin definition (P < .001) and T2 hypointensity (P < .013), with a diagnostic accuracy 95% and 78.33% respectively. Study of the TIC type on DCE-MRI revealed statistically significant difference between benign and malignant lesions (P < .001) and diagnostic accuracy 96.55%. There was no statistically significant difference (P = .181) between the ADC values of benign and malignant lesions. ROC curve analysis revealed that by using ADC cut-off value of 1 × 10?3 mm2/s had accuracy of 84.62% respectively for differentiating Warthin from malignant tumours that could be modified to higher value (94.28%) by excluding lymphoma from malignant lesions. By using cutoff value of 1.3 × 10?3 mm2/s to differentiate pleomorphic adenoma from malignancy, ROC curve analysis had high accuracy of 97.06%.ConclusionMultiparametric MRI can be used for differentiation of malignant from benign parotid tumours and characterization of some benign parotid tumours.  相似文献   
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