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991.
992.
993.
We describe a rare case of familial Cushing's disease occurring in a 7-year-old boy, and 19 years of follow up. Our patient first presented soon after his maternal aunt had been treated for Cushing's disease. The clinical presentation was made complicated by the development of an intercurrent eating disorder resembling anorexia nervosa. This resulted in marked weight loss, and even though serum and urinary cortisol levels were elevated, many of the clinical stigmata of Cushing's disease were absent. Eating disorders are relatively uncommon in boys, and in this case there was an organic cause for the abnormal behaviour. This case shows, furthermore, that even the obesity of Cushing's disease can be overcome by the combination of diet and exercise.  相似文献   
994.
The squamous odontogenic tumor is a rare odontogenic neoplasm occurring primarily in the anterior maxilla and posterior mandible. The clinical presentation is that of tooth mobility with a semicircular or triangular, well-defined radiolucent area. Histologic features include dense fibrous connective stroma with scattered islands of bland epithelium exhibiting no ameloblastomatous features. Conservative surgical treatment in most cases is sufficient; however, lesions in the maxilla may require more extensive surgical procedures to ensure resolution.  相似文献   
995.
Improvements in both mechanical circulatory support devices and immune therapy promise a wider use of sequential mechanical support as a bridge to orthotopic cardiac transplantation. The intra-aortic balloon pump, the left and right ventricular assist pumps, and the pneumatic artificial heart represent the range of devices capable of keeping a patient alive who is awaiting a donor organ. The major difficulty in using circulatory support devices is infection, which is caused by their required percutaneous tubes. We report here our experiences with mechanical circulatory support devices as a bridge to cardiac transplantation. In a series of 31 consecutive transplant procedures, six patients have required preoperative mechanical circulatory support. The intra-aortic balloon pump was used in two patients for 2 and 14 days, respectively, before transplantation. Both patients are well 10 and 11 months after the transplant procedure. Two patients required the left ventricular assist device for 11 and 21 days and are alive 3 weeks and 8 months, respectively, after transplantation. One patient was supported by the pneumatic artificial heart for 10 days before a donor heart became available but died of septic shock 17 days after transplantation. A second patient received a pneumatic artificial heart 7 days after transplantation when the heart transplant failed. He has been in stable condition for 45 days but is recovering from renal failure. Our early experiences indicate that either partial or total mechanical support as a bridge to transplantation is successful if overwhelming sepsis or renal failure can be avoided.  相似文献   
996.
The effect of ethanol on bone mineral   总被引:2,自引:0,他引:2  
Chronic alcoholics frequently have osteopenia. This usually leads to an increase in long bone fractures. The exact cause of these changes is unknown. They could be caused by a change in the calcium metabolism or a change in the organic phase of bone. To elucidate the exact mechanism by which these changes occur, the following study was done. Forty-six Sprague-Dawley rats were divided into four groups. Two groups received alcohol, and two groups served as control. One set of each group received a fracture to the leg in order to study any change that might occur in the organic phase of bone. Our findings in these animals demonstrated that alcohol causes osteopenia due to a change in calcium metabolism and does not appear to effect the organic phase of bone.  相似文献   
997.
Adult Schistosoma mansoni proteins were fractionated on polyacrylamide slab gels, recovered by electrophoretic elution and used for immunization of Fischer rats. Three antisera recognizing, respectively, 28, 78 and 85 kDa antigens were obtained. The 28 kDa antigen was found among the in vitro translation products from adult worm RNA, and among the 125I-labelled surface antigens of S. mansoni schistosomula. The isoelectric point of the 28 kDa antigen was 6.3-6.5. The 28 kDa antiserum mediated a cytotoxic activity against schistosomula when used in an in vitro assay in the presence of a purified eosinophil cell population.  相似文献   
998.
Evidence for capping of Fcγ receptors on osteoclasts   总被引:1,自引:0,他引:1  
Summary Fc receptors, cell surface structures which bind the Fc portion of immunoglobulins, facilitate endocytosis and mediate triggered enzyme release in the phagocytic cells of the mononuclear phagocyte system (MPS). The osteoclast and the macrophage share many similarities, and it has been suggested that they are both derived from a common MPS precursor cell. Nevertheless, Fcγ receptors, found on both primitive and well-differentiated cells of the mononuclear phagocyte system, have yet to be demonstrated on the osteoclast cell membrane. The aim of the present study was first, to study the distribution of rat endogenous IgG around resorbing bone using immunohistochemistry and the avidin-biotin-peroxidase (ABC) technique; and second, to determine if rat osteoclasts express Fcγ receptors, using a recently described technique based on the ABC method. Observations that endogenous IgG accumulated at osteoclast/bone interfaces, and that Fcγ receptors, expressed by osteoclasts, “capped” in the same area, have important implications regarding the origin of this cell and its mechanisms of bone attachment and resorption.  相似文献   
999.
1000.
In patients with acquired immunodeficiency syndrome (AIDS), mycobacterial diseases are leading opportunistic infections. The reasons for the peculiar propensity for disseminated infection with Mycobacterium avium complex (MAC) remain unclear. We have previously examined, in detail, the ability of monocytes from healthy donors to take up and kill MAC under both nonopsonic and opsonic conditions. We have now evaluated the in vitro ability of peripheral blood monocytes from HIV(+) patients to take up and kill MAC organisms, and have discovered a reduced ability under both nonopsonic and opsonic conditions. This reduction is due to: 1) apparent defect (s) in the phagocytes themselves, and 2) substance (s) in the HIV(+) serum which actively suppresses phagocyte activity.  相似文献   
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