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11.
International Journal of Legal Medicine - Tooth development is widely used for age estimation and staging physical maturity. It is of great importance in dental age estimation in forensic...  相似文献   
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Low-level laser therapy (LLLT) is a form of photon therapy which can be a non-invasive therapeutic procedure in cancer therapy using low-intensity light in the range of 450–800 nm. One of the main functional features of laser therapy is the photobiostimulation effects of low-level lasers on various biological systems including altering DNA synthesis and modifying gene expression, and stopping cellular proliferation. This study investigated the effects of LLLT on mice mammary tumor and the expression of Let-7a, miR155, miR21, miR125, and miR376b in the plasma and tumor samples. Sixteen mice were equally divided into four groups including control, and blue, green, and red lasers at wavelengths of 405, 532, and 632 nm, respectively. Weber Medical Applied Laser irradiation was carried out with a low power of 1–3 mW and a series of 10 treatments at three times a week after tumor establishment. Tumor volume was weekly measured by a digital vernier caliper, and qRT-PCR assays were performed to accomplish the study. Depending on the number of groups and the p value of the Kolmogorov-Smirnov test of normality, a t test, a one-way ANOVA, or a non-parametric test was used for data analyses, and p?<?0.05 was considered to be statistically significant. The average tumor volume was significantly less in the treated blue group than the control group on at days 21, 28, and 35 after cancerous cell injection. Our data also showed an increase of Let-7a and miR125a expression and a decrease of miR155, miR21, and miR376b expression after LLLT with the blue laser both the plasma and tumor samples compared to other groups. It seems that the non-invasive nature of laser bio-stimulation can make LLLT an attractive alternative therapeutic tool.  相似文献   
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Evaluation of acute percutaneous coronary intervention(PCI) results and longterm follow-up remains challenging with ongoing stent designs. Several imaging tools have been developed to assess native vessel atherosclerosis and stent expansion, improving overall PCI results and reducing adverse cardiac events. Quantitative coronary analysis has played a crucial role in quantifying the extent of coronary artery disease and stent results. Digital stent enhancement methods have been well validated and improved stent strut visualization. Intravascular imaging remains the gold standard in PCI guidance but adds costs and time to the procedure. With a recent shift towards non-invasive imaging assessment and coronary computed tomography angiography imaging have shown promising results. We hereby review novel stent visualization techniques used to guide PCI and assess stent patency in the modern PCI era.  相似文献   
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In this work, a novel n-type CdS nanorods/p-type LaFeO3 (CdS NRs/LFO) nanocomposite was prepared, for the first time, via a facile solvothermal method. The as-prepared n-CdS NRs/p-LFO nanocomposite was characterized by using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), UV-visible diffuse reflection spectroscopy (DRS), vibrating sample magnetometry (VSM), photoluminescence (PL) spectroscopy, and Brunauer–Emmett–Teller (BET) surface area analysis. All data revealed the attachment of the LFO nanoparticle on the surface of CdS NRs. This novel nanocomposite was applied as a novel visible light photocatalyst for the degradation of methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) dyes under visible-light irradiation. Under optimized conditions, the degradation efficiency was 97.5% for MB, 80% for RhB and 85% for MO in the presence of H2O2 and over CdS NRs/LFO nanocomposite. The photocatalytic activity of CdS NRs/LFO was almost 16 and 8 times as high as those of the pristine CdS NRs and pure LFO, respectively. The photocatalytic activity was enhanced mainly due to the high efficiency in separation of electron–hole pairs induced by the remarkable synergistic effects of CdS and LFO semiconductors. After the photocatalytic reaction, the nanocomposite can be easily separated from the reaction solution and reused several times without loss of its photocatalytic activity. Trapping experiments indicated that ·OH radicals were the main reactive species for dye degradation in the present photocatalytic system. On the basis of the experimental results and estimated energy band positions, the mechanism for the enhanced photocatalytic activity was proposed.

A novel n–p CdS nanorods/LaFeO3 (CdS NRs/LFO) heterojunction nanocomposite was prepared via a solvothermal route and applied as a visible-light photocatalyst for enhanced degradation of organic dye pollutants.  相似文献   
15.
PH type 2 is caused by decreased activity of GRHPR enzyme that eventually leads to ESRD and systemic oxalosis. Here, we describe an Iranian pediatric patient with PH2 and early ESRD development who received recommended treatment by undergoing isolated kidney transplantation. Diagnosis criteria included a history of reoccurring calcium oxalate renal stones and elevated oxalate levels combined with liver biopsy and decreased enzymatic activity at age five. ESRD prompted transplantation and was performed at age nine. On Day 12 post‐op, his serum creatinine level increased. A graft biopsy showed calcium oxalate crystal deposits in renal tubes with no evidence of acute rejection, which resolved with intensive hydration and administration of a potassium citrate solution. Subsequent biopsies confirmed results found in first biopsy. Despite the immunosuppressive therapy, his serum creatinine level increased again after 11 months. Renal tubular obstruction then led to graft nephrectomy. Pathological analysis of tissue confirmed findings of past biopsies. This was a very rare case of early ESRD in PH2 resulting in a failed isolated kidney transplant. As the GRHPR enzyme is predominantly expressed in liver, we suggest a combined liver‐kidney transplant may be beneficial in patients with PH2.  相似文献   
16.
Gastroesophageal reflux as cause of chronic respiratory symptoms   总被引:5,自引:0,他引:5  
Objective : Gastroesophageal reflux (GER) is a relatively common disorder in infants and children. It maybe associated with severe complications. The coexistence of GER and a wide range of respiratory symptoms has been reported. The purpose of our study was to investigate the relationship between chronic respiratory symptoms and GERD as an underlying cause. To our knowledge, there is not a method known study for identifying this relationship and prevalence in our area.Methods : The study group consists of fifty-two (4 months-10 years) children who were referred to pediatric surgery ward for evaluation of GERD as a cause of chronic respiratory symptoms by 24 hours PH monitoring. Additionally, 10 patients with only one episode of pneumonia were evaluated as the control group. Chronic respiratory presentations include the following: chronic cough, recurrent pneumonia, asthma, and respiratory distress.Results : 24 hour esophageal PH monitoring revealed GER in 22 (42.2%) patients as a cause of their chronic respiratory symptoms, while (30 (57.7%) children did not show any evidence of GER. GER was detected in 11 of 24 (45.7%) patients with chronic cough. Thirty-three patients presented with recurrent pneumonia, 13(39.9%) of whom had GER. In 8 patients with asthma, GER was found in 4 cases. None of the 6 patients with respiratory distress had GERD.Conclusion : The possibility of GERD was significantly higher in study group (children with chronic respiratory symptoms) compared to control group (p-value<0.01). All patients with chronic cough, recurrent pneumonia and asthma should be aggressively investigated for the possibility of GER. Documenting abnormal gastroesophageal reflux helps direct appropriate therapy before occurrence of major complications.  相似文献   
17.
The aim of this study was to evaluate the effect of maxillary first molar rotation on arch length in patients whose Class II, division 1 malocclusion was treated with a straight-pull headgear. The sample included 19 children who represent a subset of a population enrolled for 2 years in a prospective clinical trial of Class II treatment. The inner bow was adjusted at monthly visits and the average distalizing force was 14-16 oz per side. Measurements were made with digital calipers on casts obtained at baseline and at a time point averaging 16 months (SD 3 months) into treatment. Molar movement was related to a coordinate system referenced to the midpalatal raphae and the occlusal plane through a palatal plug that could be transferred to successive casts of the same patient. Distances from the cusp tips were measured to the reference system. The distal and lateral displacement, and the rotation of the molars over time were then computed. High correlations were observed between molar rotation and tooth displacement (that is the net differential movement between the mesiobuccal - MB - and mesiopalatal - MP - cusps): r=0.9, p=0.0001 (left side); r=0.8, p=0.0001 (right side). The average rotation of the molar was 15.4 degrees (SE+/-3.80) on the left side and 10.8 degrees (SE+/-2.20) on the right side. The average differential displacements between the MB and MP cusps were 1.04 mm (SE+/-0.29) (left) and 0.73 mm (SE+/-0.23) (right). The differences between the two sides were not statistically significant. The molar rotation did not correlate with any of the following parameters: initial tooth position; initial distance between the MB and MP cusps as a correlate of molar anatomy; transverse (mostly buccal) movement of the MB and MP cusps; distal movement of the tooth, as measured by the total displacement of the MB and MP cusps. This study qualifies the relationship between molar rotation and increase in arch length. The mean total distal movement of the molar was larger (nearly 3 mm) than the average contribution of molar rotation to space gain (about 1 mm), suggesting that the distal movement of the tooth was a combination of rotation and translation (or tipping). The contribution of the molar rotation is more significant with a smaller total displacement of the tooth.  相似文献   
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Introduction  Kaposi’s sarcoma (KS) is one of the most common tumors to occur in kidney recipients, especially in the Middle East countries. Limited data with adequate sample size exist about the development of KS in living kidney recipients. Methods  Therefore, we made a plan for a multicenter study, accounting for up to 36% (n = 7,939) of all kidney transplantation in Iran, to determine the incidence of KS after kidney transplantation between 1984 and 2007. Results  Fifty-five (0.69%) recipients who developed KS after kidney transplantation were retrospectively evaluated with a median follow-up of 24 (1–180) months. KS occurred more often in older age when compared to patients without KS (49 ± 12 vs. 38 ± 15 years, P = 0.000). KS was frequently found during the first 2 years after transplantation (72.7%). Skin involvement was universal. Furthermore, overall mortality rate was 18%, and it was higher in patients with visceral involvement compared to those with mucocutaneous lesions (P = 0.01). However, KS had no adverse affect on patient and graft survival rates compared to those without KS. Forty-four patients with limited mucocutaneous disease and four with visceral disease responded to withdrawal or reduction of immunosuppression with or without other treatment modalities. Renal function was preserved when immunosuppression was reduced instead of withdrawn in patients with and without visceral involvement (P = 0.001 and 0.008, respectively). Conclusion  The high incidence of KS in this large population studied, as compared to that reported in other transplant patient groups, suggests that genetic predisposition may play a pathogenetic role.  相似文献   
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