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1.
Although histopathology is the time‐honored gold standard diagnostic measure in dermatology, several factors may detract from an accurate microscopic diagnosis. Limiting factors include: human error, suboptimal biopsy‐site selection or biopsy technique, and inherent restrictions of vertical tissue sectioning that lead to incomplete microscopic evaluation of the lesion. Reflectance confocal microscopy (RCM) is a non‐invasive imaging tool that allows for the cellular‐level examination of the lesion, at a horizontal plane, which may complement the subsequent vertical histopathological tissue examination. Herein, we report a case series whereby prebiopsy RCM examination enhanced the accuracy of histopathological diagnosis or allowed for a critical appraisal of initial histopathological misdiagnosis.  相似文献   
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Curcumin nanoparticles were most recently considered in medical research because of their antibacterial properties. The main objective of the study was to develop the green synthesis and antibacterial activity of curcumin nanoparticles using Curcuma longa. The processing of curcumin nanoparticles was carried out after the collection, identification, and extraction of curcumin. The effect of a sample on the synthesis of nanoparticles, such as curcumin aqueous concentrations (5, 10, and 20 mg/ml) and curcumin nanoparticles (5, 10, and 20 mg/ml), and the antibacterial effect of these nanoparticles on Escherichia coli, Staphylococcus aureusPseudomonas aeruginosa, Klebsiella pneumoniae, and the fungal strain Aspergillus niger. For examining antibacterial and anti-fungal activity disc diffusion method was performed, followed by the zone of inhibition. According to X-ray diffraction and scanning electron microscope analysis, nanoparticles have spherical shapes and size of 42.64 nm. Results showed that a high dose of 20 mg/ml curcumin nanoparticles have more antibacterial activity than curcumin extracts in E. coli as it showed the largest diameter of zone of inhibition as compared to other doses. Other bacterial and fungal strains also showed significant results but E. coli was most prominent. The biosynthesis of curcumin nanoparticles using an aqueous extract of C. longa is a clean, inexpensive, and safe method that has not been used any toxic substance and consequently does not have side effects. Since several pathogenic species have acquired antibiotic resistance, the combination of curcumin with various nanoparticles would be beneficial in the cure of pathogenic diseases.  相似文献   
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Expression of thioredoxin-interacting protein (TxNIP), an endogenous inhibitor of the thiol oxidoreductase thioredoxin, is augmented by high glucose (HG) and promotes oxidative stress. We previously reported that TxNIP-deficient mesangial cells showed protection from HG-induced reactive oxygen species, mitogen-activated protein kinase phosphorylation, and collagen expression. Here, we investigated the potential role of TxNIP in the pathogenesis of diabetic nephropathy (DN) in vivo. Wild-type (WT) control, TxNIP−/−, and TxNIP+/− mice were rendered equally diabetic with low-dose streptozotocin. In contrast to effects in WT mice, diabetes did not increase albuminuria, proteinuria, serum cystatin C, or serum creatinine levels in TxNIP−/− mice. Whereas morphometric studies of kidneys revealed a thickened glomerular basement membrane and effaced podocytes in the diabetic WT mice, these changes were absent in the diabetic TxNIP−/− mice. Immunohistochemical analysis revealed significant increases in the levels of glomerular TGF-β1, collagen IV, and fibrosis only in WT diabetic mice. Additionally, only WT diabetic mice showed significant increases in oxidative stress (nitrotyrosine, urinary 8-hydroxy-2-deoxy-guanosine) and inflammation (IL-1β mRNA, F4/80 immunohistochemistry). Expression levels of Nox4-encoded mRNA and protein increased only in the diabetic WT animals. A significant loss of podocytes, assessed by Wilms’ tumor 1 and nephrin staining and urinary nephrin concentration, was found in diabetic WT but not TxNIP−/− mice. Furthermore, in cultured human podocytes exposed to HG, TxNIP knockdown with siRNA abolished the increased mitochondrial O2 generation and apoptosis. These data indicate that TxNIP has a critical role in the progression of DN and may be a promising therapeutic target.  相似文献   
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Purpose:Osteochondral lesion of talus(OLT)is one of the common causes of ankle pain.This disorder is common in young athletes after ankle injury.There are various therapeutic options.One of the options is mosaic plasticizer.The purpose of this study was to investigate the effect of mosaicplasty on improvement of symptoms of patients with osteochondral lesions of talus.Methods:Nineteen patients with osteochondral lesions of talus participated in this study,who were treated with mosaicplasty.Before and after treatment,pain(visual analogue scale),function(American Orthopaedic Foot and Ankle Society),range of motion and radiographic signs were evaluated.Results:The results of this study showed that mosaicplasty could significantly reduce pain,increase function and improve radiographic symptoms.The range of motion increased after treatment,which was not significant.Conclusion:We can confirm the effect of mosaicplasty on the improvement of patients with osteochondral lesions of the ankle,suggesting it as a treatment option.  相似文献   
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Pulmonary carcinoid tumors occur in both central and peripheral locations, and some differences in clinico-pathological features have long been observed. We investigated a large number of resected carcinoid tumors with the aim to further define the characteristics of tumors from both locations. One hundred sixty-six resected carcinoid tumors of the lung were analyzed for a variety of clinical and pathologic features, including histology subtype, mitotic rate, Ki67 index, necrosis, invasive pattern, architectural pattern, cell morphology, sustentacular cells, neuroendocrine hyperplasia, and orthopedia homeobox protein (OTP) and TTF-1 immunohistochemical expressions. Unsupervised hierarchical cluster analysis suggested three clusters as the best solution using TTF-1 and OTP expression: TTF-1-positive and OTP-positive tumors as cluster 1, TTF-1-positive but OTP-negative as cluster 2, and TTF-1-negative and OTP-negative as cluster 3. Cluster 1 was characterized by peripheral location, presence of spindle cell component, presence of sustentacular cells, female predominance, and strong association with neuroendocrine hyperplasia. Cluster 2 was characterized by central location, polygonal cell morphology, acinar growth pattern in a subset of tumors, and only rare association with neuroendocrine hyperplasia. Cluster 3 consisted of more aggressive tumors with more heterogeneous pathologic features. Tumors showed polygonal cell morphology and acinar growth pattern. Occurrence of neuroendocrine hyperplasia was exceptional. Our study confirmed distinct characteristics of central and peripheral type carcinoid. An important difference was a strong association of the peripheral tumor with neuroendocrine hyperplasia while such an association in central tumors was negligible. The tumor location might be relevant for pathobiology of lung carcinoid tumors.  相似文献   
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In contrast to the conventional radiotherapy/chemoradiotherapy paradigms used in the treatment of majority of cancer types, this review will describe two areas of radiobiology, hyperfractionated and hypofractionated radiation therapy, for cancer treatment focusing on application of novel concepts underlying these treatment modalities. The initial part of the review discusses the phenomenon of hyper-radiation sensitivity (HRS) at lower doses (0.1 to 0.6 Gy), describing the underlying mechanisms and how this could enhance the effects of chemotherapy, particularly, in hyperfractionated settings. The second part examines the radiobiological/physiological mechanisms underlying the effects of high-dose hypofractionated radiation therapy that can be exploited for tumor cure. These include abscopal/bystander effects, activation of immune system, endothelial cell death and effect of hypoxia with re-oxygenation. These biological properties along with targeted dose delivery and distribution to reduce normal tissue toxicity may make high-dose hypofractionation more effective than conventional radiation therapy for treatment of advanced cancers. The novel radiation physics based methods that take into consideration the tumor volume to be irradiated and normal tissue avoidance/tolerance can further improve treatment outcome and post-treatment quality of life. In conclusion, there is enough evidence to further explore novel avenues to exploit biological mechanisms from hyper-fractionation by enhancing the efficacy of chemotherapy and hypo-fractionated radiation therapy that could enhance tumor control and use imaging and technological advances to reduce toxicity.KEYWORDS : Low Doses Fractionated Radiation Therapy (LDFRT), hyper-radiation sensitivity (HRS), induced radiation resistance (IRR), hyperfractionation, chemopotentiation, stereotactic body radiation therapy (SBRT), stereotactic ablative radiosurgery (SARS), stereotactic ablative radiotherapy (SABR), stereotactic radiosurgery (SRS), spatially fractionated GRID radiotherapy (SFGRT), lattice  相似文献   
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The exact risk association of coronavirus disease 2019 (COVID-19) for surgeons is not quantified which may be affected by their risk of exposure and individual factors. The objective of this review is to quantify the risk of COVID-19 among surgeons, and explore whether facemask can minimise the risk of COVID-19 among surgeons. A systematised review was carried out by searching MEDLINE to locate items on severe acute respiratory syndrome coronavirus 2 or COVID-19 in relation to health care workers (HCWs) especially those work in surgical specialities including surgical nurses and intensivists. Additionally, systematic reviews that assessed the effectiveness of facemask against viral respiratory infections, including COVID-19, among HCWs were identified. Data from identified articles were abstracted, synthesised and summarised. Fourteen primary studies that provided data on severe acute respiratory syndrome coronavirus 2 infection or experience among surgeons and 11 systematic reviews that provided evidence of the effectiveness of facemask (and other personal protective equipment) were summarised. Although the risk of COVID-19 could not be quantified precisely among surgeons, about 14% of HCWs including surgeons had COVID-19, there could be variations depending on settings. Facemask was found to be somewhat protective against COVID-19, but the HCWs’ compliance was highly variable ranging from zero to 100%. Echoing surgical societies’ guidelines we continue to recommend facemask use among surgeons to prevent COVID-19.  相似文献   
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Screening for peripheral neuropathy in chemical warfare victims   总被引:1,自引:0,他引:1  
We aimed to assess the prevalence of peripheral neuropathy in chemical warfare victims. We speculated that peripheral neuropathy is a late complication of exposure to chemical warfare agents. Late complications of exposure to chemical warfare agents are not well known and are poorly discussed in the existing literature. Scientific data regarding delayed complications are sparse, but this warrants recognition, especially when the clinician has to treat chemical warfare victims. The hazards of organophosphate pesticides and several toxins, although recognized to some extent, are, however, different from the hazards of chemical warfare agents which are far more serious. In this study, 100 chemical warfare patients, with varying degrees of exposure and an average age of 37.2+/-9.0 years, were examined clinically and studied electrodiagnostically from January 2002 to January 2003. Five of these patients proved to be suffering from axonal neuropathy. This rate was significantly higher than that found in the normal population. Our data indicate that chemical warfare agents may cause peripheral neuropathy in chemical warfare victims. In conclusion, organophosphorous agents used against Iranian troops during the war on Iran correlate with delayed neuropathy in these victims.  相似文献   
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