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1.
Kinase alterations are increasingly recognised as oncogenic drivers in mesenchymal tumours. Infantile fibrosarcoma and the related renal tumour, congenital mesoblastic nephroma, were among the first solid tumours shown to harbour recurrent tyrosine kinase fusions, with the canonical ETV6::NTRK3 fusion identified more than 20 years ago. Although targeted testing has long been used in diagnosis, the advent of more robust sequencing techniques has driven the discovery of kinase alterations in an array of mesenchymal tumours. As our ability to identify these genetic alterations has improved, as has our recognition and understanding of the tumours that harbour these alterations. Specifically, this study will focus upon mesenchymal tumours harbouring NTRK or other kinase alterations, including tumours with an infantile fibrosarcoma-like appearance, spindle cell tumours resembling lipofibromatosis or peripheral nerve sheath tumours and those occurring in adults with a fibrosarcoma-like appearance. As publications describing the histology of these tumours increase so, too, do the variety kinase alterations reported, now including NTRK1/2/3, RET, MET, RAF1, BRAF, ALK, EGFR and ABL1 fusions or alterations. To date, these tumours appear locally aggressive and rarely metastatic, without a clear link between traditional features used in histological grading (e.g. mitotic activity, necrosis) and outcome. However, most of these tumours are amenable to new targeted therapies, making their recognition of both diagnostic and therapeutic import. The goal of this study is to review the clinicopathological features of tumours with NTRK and other tyrosine kinase alterations, discuss the most common differential diagnoses and provide recommendations for molecular confirmation with associated treatment implications.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To estimate the impact of delayed care during the coronavirus disease 2019 (COVID-19) pandemic on the outcomes of patients with...  相似文献   
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The purpose of the study was to investigate potential associations between tumour necrosis factor (TNF), soluble TNF receptors (sTNF-Rs), immunoglobulin (Ig)G subclasses and development of cytomegalovirus (CMV) disease amongst human immunodeficiency virus (HIV)-1 patients. We enrolled HIV-1 patients with CD4 counts less than 100/μl in a prospective study and followed them over 1 year for development of CMV disease. Concentrations of TNF, sTNF-RI, sTNF-RII and IgG subclass reactivities were measured by ELISA; levels of CMV pp65 antigenaemia were determined as numbers of pp65 expressing cells/100 000 cells and were measured by staining of leucocytes; and HIV-1 RNA loads were measured by polymerase chain reaction (PCR). Eighteen patients studied with CMV disease had higher levels of sTNF-RI than 18 similar patients without CMV disease. Concentrations of sTNF-RI correlated with levels of CMV antigenaemia in blood samples collected before the development of CMV disease. Patients with CMV disease had lower levels of IgG1 reactivities to CMV than patients without CMV disease. We conclude that increased levels of sTNF-RI and decreased IgG1 reactivities are associated with an increased risk of development of CMV disease among HIV-1 patients.  相似文献   
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The radiographic findings in 24 cases of bronchiolitis obliterans with organizing pneumonia and 16 cases of usual interstitial pneumonia were reviewed and compared. Some cases of bronchiolitis obliterans with organizing pneumonia have been mistaken for usual interstitial pneumonia, although the two diseases have distinct pathologic findings. Clinically, the diseases often have different manifestations. Bronchiolitis obliterans with organizing pneumonia has a better prognosis and often responds well to steroids. This study shows that the radiologic findings of bronchiolitis obliterans include alveolar opacities without lung-volume loss. Patients with usual interstitial pneumonia, however, have bilateral diffuse interstitial opacities with occasional honeycomb changes, and there is loss of lung volume in most patients. These findings suggest that the chest radiograph can aid in distinguishing the two diseases.  相似文献   
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Human Tattoo   总被引:2,自引:0,他引:2  
Ultrathin serial sections of human biopsy specimens, taken at 24 hours, 1 month, and 1, 3, and 40 years post-tattooing were examined under the electron microscope. The ink particles found in cells were measured and compared with control ink particles embedded in agar. Freshly tattooed skin showed an inflammatory reaction followed by ultrastructural necrosis. The time of healing, about 1 month from introduction of ink to complete healing, has been divided into three phases: inflammatory reaction and necrosis, formation of basement membrane, and normal epidermis and dermis. Once the skin showed normal ultrastructure, ink particles were found only in dermal fibroblasts.  相似文献   
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Endometriosis in episiotomy scar with anal sphincter involvement   总被引:2,自引:1,他引:1  
A case of endometriosis in an episiotomy scar with involvement of the external anal sphincter is presented. The clinical, operative, and pathologic findings are reported. The question of etiology and treatment is discussed, and the literature is reviewed. Wide excision of the ectopic endometrial tissue with primary reconstruction of the external sphincter was curative, and the functional result was excellent. It is suggested that this treatment policy should be recommended for these cases.  相似文献   
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