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71.
Interferon alpha (IFN-alpha) can be effective therapy for patients with chronic kidney disease who have chronic hepatitis C (HCV). However, acute allograft rejection has been reported in association with IFN-alpha following kidney transplantation, and therefore IFN therapy is recommended prior to, rather than after, kidney transplantation whenever feasible. The special case of repeat allograft recipients who contract HCV after the first transplantation presents special difficulties. This report features the case of a repeat allograft recipient who presented with neutropenic fevers after 5 months of pegylated IFN-alpha therapy, initiated 6 months following the functional loss of his third graft and the reinitiation of hemodialysis (HD). Physical exam, radiographic and laboratory findings led to allograft nephrectomy. The pathologic findings supported a diagnosis of acute-on-chronic rejection. This represents a rare case of IFN-alpha induced rejection following allograft failure and return to HD in a repeat allograft recipient. It also calls attention to the need for a high index of suspicion for the development of allograft rejection, which may require allograft nephrectomy even after allograft 'failure'.  相似文献   
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73.
A patient with hepatitis C virus (HCV) infection was diagnosed with cutaneous, pulmonary and hepatic sarcoidosis following interferon alpha therapy. There are only a few cases of sarcoidosis associated with this treatment. This is the first case who not only developed sarcoidosis, but also autoimmune hypothyroidism and thrombocytopenia during interferon alpha therapy due to the immunomodulatory effects of the drug.  相似文献   
74.
Antibody-mediated rejection of human cardiac transplants is correlated with C4d deposits and macrophage infiltrates in capillaries of endomyocardial biopsies. We produced an antibody to rat C4d to study C4d deposition and clearance in Lewis rats that were sensitized with a blood transfusion from DA rats 7, 14 or 21 days before cardiac transplantation. Cyclosporin A (CsA) immunosuppression was initiated after transplantation at a dose that inhibited graft rejection, antibody production and C4d deposition in unsensitized recipients. Blood transfusion elicited high levels of circulating IgG alloantibodies, predominantly of the complement-activating IgG2b subclass, that peaked 14 days after transplantation. At this time, macrophages accumulated in capillaries, and C4d deposits were diffuse and intense on arteries, capillaries and veins. Grafts that survived 90 days in sensitized recipients still had deposits of C4d that were associated with increased interstitial fibrosis and vasculopathy in arteries. Clearance of C4d was determined by retransplanting DA cardiac allografts from Lewis recipients back to DA recipients. C4d deposits were decreased to minimal levels within 5 days after retransplantation. Thus, C4d deposition is not limited to the capillaries, but extends throughout the arterial tree, and despite formation of a covalent bond, C4d is cleared within days.  相似文献   
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76.
对HCV血清标记阳性的静脉内毒瘤者进行半年和15个月随访,并调查影响转归的部分因素。结果显示,静脉内毒瘾者抗-HCV自然转阴率分别为11.0/和33.3%。单因素和多因素分析均提示转阴率以婚姻状况良好的已婚者较离婚者高、人均年收入高者较低者高,说明婚姻状况和人们的经济水平对毒瘾者抗-HCV转阴有一定的影响。  相似文献   
77.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
78.
Behcet's disease (BD) is characterized by recurrent oral aphthae, skin lesions, eye lesions, and genital ulceration. To determine the pathogenesis of BD, we performed histological and immunohistochemical studies of these mucocutaneous lesions, an assay of neutrophil activity, and HLA typing. Dense dermal or subcutaneous infiltrations of polymorphonuclear cells (PMN) without leukocytoclastic vasculitis were found in 28 of 57 lesions. Immunohistochemically, deposits of C3 on the vessels were found in 12 of 31 lesions. Deposits of immunoglobulin were not found except for one of IgM. C3 deposits and PMN infiltrations were significantly related (p<0.05). PMN activity by polarization was enhanced; however, the results did not show a significant relationship with the PMN infiltrations or the C3 deposits. The incidence of HLA-B51 was significantly high in BD, but no significant relationship was found between HLA-B51 and the results of other examinations. These results suggest that the pathogenesis of BD lesions differs from that of collagen diseases and that C3 deposits on the vessels may play an important role in the development of mucocutaneous lesions where PMN have mainly infiltrated.  相似文献   
79.
Our new finding of de novo synthesis and secretion of C3 by both murine peritoneal macrophages and polymorphonuclear leukocytes (PMN) was confirmed by the incorporation of [35S]methionine into C3 molecules and their complete inhibition by cycloheximide. The methods of secretion of C3 from these two types of cells were compared by examining the C3 contents in their culture supernatants. Completely different modes of secretion were observed, i.e. although macrophages synthesize and secrete C3 constitutively, PMN has a mechanism to store the already synthesized C3 in the cell and secrete it in response to stimuli. Protein kinase C (PKC) activators, e.g. 12-O-tetradecanoyl-phorbol 13-acetate, dioctanoyl glycerol, and mezerein, as well as calcium ionophore A23187 stimulate the secretion of C3 from PMN. These results suggest the involvement of PKC and the calmodulin pathway. A very sensitive method for measuring C3 activity was developed which enabled us to show for the first time that C3 secreted by PMN had opsonizing activity and that particles cultured with PMN were phagocytosed effectively.  相似文献   
80.
本文采用热变性温度法和液相复性速率法对—轻型特征及血清学反应相似米克戴德军团菌(Lm)的菌株进行了测定,结果表明该菌与标准Lm(C DC株)的DNA G Cmol%相差3.45%,与标准Lm(C DC株)的DNA同源性达81.99%,根据伯杰细菌鉴定手册(1984),可判定该菌株与标准Lm(C DC株)为遗传型一致的类群,即从遗传学角度证明该菌为Lm。  相似文献   
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