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81.
82.
In 2014, the renal allograft biopsy still represents the best available diagnostic ‘gold’ standard to assess reasons for allograft dysfunction. However, it is well recognized that histological lesion observed in the biopsy is of limited diagnostic specificity and that the Banff classification as the international diagnostic standard represents mere expert consensus. Here, we review the role of the renal allograft biopsy in different clinical and diagnostic settings. To increase diagnostic accuracy and to compensate for lack of specificity, the interpretation of biopsy pathology needs to be within the clinical context, primarily defined by time post‐transplantation and patient‐specific risk profile. With this in mind, similar histopathological patterns will lead to different conclusions with regard to diagnosis, disease grading and staging and thus to patient‐specific clinical decision‐making. Consensus generation for such integrated diagnostic approach, preferably including new molecular tools, represents the next challenge to the transplant community on its way to precision medicine in transplantation.  相似文献   
83.
Primary small cell carcinoma of the prostate is extremely rare. Herein reported is a case of primary small cell carcinoma of the prostate with immunohistochemical examination of KIT and platelet‐derived growth factor‐α. The present case is unique in that the small cell carcinoma did not express neuroendocrine antigens. A 68‐year‐old man was found to have high serum prostate‐specific antigen, and biopsy showed malignant small tumor cells fulfilling the small cell carcinoma criteria of the World Health Organization. Immunohistochemically, tumor cells were positive for pan‐cytokeratin, KIT, platelet‐derived growth factor‐α, p53, Ki‐67 labeling = 65%, prostate‐specific antigen and alpha‐methylacyl‐CoA racemase. Tumor cells were negative for vimentin, CD56, synaptophysin, chromogranin and neuron‐specific enolase. Imaging modalities showed multiple metastases, and the patient was treated by chemotherapy. The present report is the fifth with immunohistochemistry of prostatic small cell carcinoma.  相似文献   
84.
目的探讨钙结合蛋白S100A12在小鼠重症急性胰腺炎治疗中的潜在作用。方法采用连续7次腹腔注射雨蛙素50μg/kg(每次间隔1 h)及脂多糖建立小鼠急性胰腺炎模型。将160只SPF级雌性ICR小鼠随机分为对照组(A组,生理盐水)、轻型组(B组,雨蛙素)、重症组(C组,雨蛙素+脂多糖)、干预组(D组,S100A12重组抗体+雨蛙素+脂多糖),每组40只。在首次注射雨蛙素后8 h、12 h和24 h采血,分别检测各时段血清中S100A12、淀粉酶(AMY)、C反应蛋白(CRP)、白介素(IL-1β、IL-6)、肿瘤坏死因子(TNF-α)的含量,观察小鼠胰腺的病理形态并进行评分。结果与C组相比,D组各时段血清中AMY、CRP、IL-1β、IL-6、TNF-α、S100A12含量明显降低(P0.05);与B组相比,D组各时段血清S100A12浓度明显降低(P0.05),胰腺病理形态也有明显改善。结论 S100A12重组抗体能够有效降低小鼠急性胰腺炎的严重程度,S100A12可以作为重症急性胰腺炎治疗的一个有效靶点。  相似文献   
85.
86.
To explore the relationship of peripheral nerve ultrastructure and its associated protein expression in experimental autoimmune neuritis (EAN). EAN was established in Lewis rats using an emulsified mixture of P0 peptide 180-199, Mycobacterium tuberculosis, and incomplete Freund’s adjuvant. Rats immunized with saline solution were used as a control group. Sciatic nerve ultrastructure and immunofluorescence histopathology were measured at the neuromuscular severity peak on day 18 post-induction. Cell-specific protein markers were used for immunofluorescence histopathology staining to characterize sciatic nerve cells: CD3 (T cell), Iba-1 (microglia), S100 (myelin), and neurofilament 200 (axon). The results showed that swelling of the myelin lamellae, vesicular disorganization, separation of the myelin lamellae, and an attenuation or disappearance of the axon were observed by transmission electron microscopy in the EAN group. CD3 and Iba-1 increased significantly in the structures characterized by separation or swelling of the myelin lamellae, and increased slightly in the structures characterized by vesicular of the myelin lamellae, S100 decreased in the structures characterized by vesicular disorganization or separation of the myelin lamellae. And neurofilament 200 decreased in the structures characterized by separation of the myelin lamellae. Furthermore, we found that Iba1 were positive in the myelin sheath, and overlapped with S100, which significantly indicated that Schwann cells played as macrophage-like cells during the disease progression of ENA. Our findings may be a significant supplement for the knowledge of EAN model, and may offer a novel sight on the treatment of Guillain-Barré syndrome.  相似文献   
87.
The extensive use of copper oxide nanoparticles (CuO‐NPs) in various industries and their wide range of applications have led to their accumulation in different ecological niches of the environment. This excess exposure raises the concern about its potential toxic effects on various organisms including humans. However, the hazardous potential of CuO‐NPs in the literature is elusive, and it is essential to study its toxicity in different biological models. Hence, we have conducted single acute dose (2000 mg/kg) and multiple dose subacute (30, 300 and 1000 mg/kg daily for 28 days) oral toxicity studies of CuO‐NPs in female albino Wistar rats following OECD guidelines 420 and 407 respectively. Blood analysis, tissue aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and acetylcholinesterase, superoxide dismutase, catalase, lipid malondialdehyde and reduced glutathione assays, and histopathology of the tissues were carried out. The higher dose treatments of the acute and subacute study caused significant alterations in biochemical and antioxidant parameters of the liver, kidney and brain tissues of the rat. In addition, histopathological evaluation of these three organs of treated rats showed significantly high abnormalities in their histoarchitecture when compared to control rats. We infer from the results that the toxicity observed in the liver, kidney and brain of treated rats could be due to the increased generation of reactive oxygen species by CuO‐NPs.  相似文献   
88.
89.
Melanotic neuroectodermal tumor of infancy is an uncommon neoplasm that normally occurs in the anterior maxilla of children less than 1 year of age. This is a tumor with controversial origin, although neural crest origin is proposed. This case report presents an analysis of histopathological and immunohistochemical findings in this rare tumor.  相似文献   
90.
Contamination of the environment with antimony compounds may affect human health through the persistent exposure to small doses over a long period. Sixty growing male albino rats, weighing 43-57 grams, utilized in this study. The animals were divided into 3 groups; each of 20 rats: animals of group I served as control, animals of group II received 6 mg/kg body weight antimony trisulfide daily for 8 weeks with drinking water, and those of group III received the same dose by the same route for 12 weeks. The Malpighian renal corpuscles showed distortion, destruction and congestion of glomerular tuft, vacuoles in the glomeruli, peritubular haemorrhage, obliteration of Bowman’s space, and thickening with irregularity of Bowman’s membrane. The proximal convoluted tubules demonstrated patchy loss of their brush border, thickening of the basement membrane with loss of its basal infoldings, disarrangement of the mitochondria, pleomorphic vacuoles in the cytoplasm, apical destruction of the cells, apical migration of the nuclei, and absence of microvilli. On the other hand, peri-tubular hemorrhage, apical vacuolation, small atrophic nuclei, swelling of mitochondria, obliteration of the lumina, destruction of cells, and presence of tissue debris in the lumina, were observed in the distal convoluted tubules. The present work demonstrated the hazardous effect of antimony on the renal function as evidenced by the significant increase of the level of blood urea, serum creatinine, and serum sodium and potassium. In conclusion, this study proposed that continuous oral administration of antimony for 8 and 12 weeks has hazardous toxic effect on the structure and function of the kidney in growing albino rat. Based on the results of the present study, it is recommended to avoid the use of any drinking water contaminated with antimony compounds and forbidden its use in infants and children foods.  相似文献   
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