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41.
Purpose:The aim of this study was to examine the pathology of retinoblastoma (RB) seeds with supportive evidence by field emission scanning electron microscopy and Raman spectroscopy.Methods:This study was a laboratory-based observational study. Enucleated eyeballs received in the ocular pathology department of a tertiary eye care center in northeast India were included in the cohort after obtaining written informed consent during the surgery. The study was carried out for 6 years (2015–2020). Most of the eyeballs were Group-E RBs. Standard eyeballs sectioning were done by bread loaf techniques. Gross documentations included RB seeds seen in the smallest calotte done with utmost care. Seeds were documented also in permanent sections. Scanning electron microscopy and Raman spectroscopy were carried out in an index case.Results:Out of the total 59 cases, 35 RB cases had different seedings. The mean age at enucleation was 2.9 years. RB seeds were seen in vitreous (n = 19), subretinal plus vitreous (n = 7), anterior chamber (n = 1), over crystalline lens (n = 3), retinal surface (n = 1), retinal pigment epithelium (RPE; n = 2), subretinal (n = 1), calcified seeds (n = 2). Other characteristics were dusts (n = 7), clouds (n = 11), spheres (n = 4), and unspecified type (n = 13). Histopathological high-risk factors showed significant choroidal (n = 22) and optic nerve (n = 15) involvement. Few cases had extraocular spread. Undifferentiated tumor (n = 24) was seen with higher evidence of necrosis (n = 23). Raman spectra differentiated the seeds from the normal tissue on the basis of lipid and protein content.Conclusion:This study highlights the different types of RB seeds with high-risk factors. The morphology of those seeds showed the difference between vitreous and subretinal seeds under advanced microscopic observations.  相似文献   
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Objective: To compare the antioxidant and anti-genotoxic properties of Alpinia (A.) galanga, Curcuma (C.) amada, and C. caesia. Methods: Cytotoxicity of ethanol...  相似文献   
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Titanium oxide coatings have been shown to exhibit desirable properties as biocompatible coatings. We report on the quantitative microstructure characterization and deformation behavior of TiO2 nanotubes on Ti substrate. Nanotubes were processed using anodic oxidation of Ti in a NaF electrolyte solution. Characterization of the as-processed coatings was conducted using scanning electron microscopy and focused ion beam milling. Increases in anodization time had no significant effect on tube diameter or tube wall thickness. Coating thickness, however, increased with time up to 2 h of anodization, at which point an equilibrium thickness was established. Nanoindentation was used to probe the mechanical response in terms of Young’s modulus and hardness. Progressively higher values of elastic modulus were obtained for thinner films consistent with increasing effects of the Ti substrate. A possible deformation mechanism of densification of the porous oxide and wear of the dense surface is suggested and discussed.  相似文献   
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Background Symmetrical peripheral gangrene (SPG) is characterized by sudden onset of peripheral, frequently symmetrical gangrene in the absence of major vascular occlusive disease. SPG is associated with a wide range of underlying medical problems and usually has disseminated intravascular coagulation (DIC) in the background. Although sporadic cases and a few retrospective case series of SPG have been reported, lack of any prospective study on the profile and outcome of these patients prompted us to undertake the present work. Objectives To study the clinical profile, aetiological factors, and outcome of a group of patients of SPG from eastern India. Patients/methods Prospective, observational study of consecutive patients presented at or referred to the Dermatology Department of a tertiary‐care hospital during 2001 to 2008. Results We observed 14 patients (5 males, 9 females; mean age: 43.36 years) of SPG during the study period. All had clinical and laboratory evidence of DIC in association with a shock syndrome. Associated purpura fulminans was noted in 11 patients. In 12 patients, the cause of SPG was infective, Pneumococcus being the commonest organism involved. Two patients developed DIC and SPG postoperatively. Nine patients survived and the remaining five patients died. Three patients had leukopenia and all of them died. Amongst the survivors, four patients had auto‐amputation of some parts of distal limbs; surgical amputation was done in two patients. Conclusions SPG carries a high mortality rate frequently requiring multiple limb amputations in survivors. Leukopenia may be a poor prognostic factor of SPG and DIC may occur universally.  相似文献   
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Though haemangioma of cheek is not a very uncommon entity, here we are presenting a case series of four such cases of haemangioma cheek of completely different presentation. One of which is classical maxillary haemangioma and the rest of the others have different and unusual presentations. They all have different radiological features and were managed successfully by different surgical approaches without any recurrence.  相似文献   
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Sequence analysis of segment 2 (seg-2) of three Indian bluetongue virus (BTV) isolates, Dehradun, Rahuri and Bangalore revealed 99% nucleotide identity amongst them and 96% with the reference BTV 23. Phylogenetic analysis grouped the isolates in ‘nucleotype D’. The deduced amino acid (aa) sequence of the Bangalore isolate showed a high variability in a few places compared to other isolates. B-cell epitope analyses predicted an epitope that is present exclusively in the Bangalore isolate. Two-way cross serum neutralization confirmed that Bangalore isolate is antigenically different from the other two isolates. The results of this study suggest that these three isolates are VP2 variants of BTV 23. This signifies that non-cross-neutralizing variants of the same BTV serotype should be included in vaccine preparation.  相似文献   
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