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51.
It is estimated that 1.7% of orthotopic liver transplant recipients will develop abdominal aortic aneurysms (AAAs) after transplantation. It has been observed that these aneurysms expand faster in transplant recipients; therefore, aggressive surveillance for AAAs in transplant recipients is required. Endovascular aneurysm repair is rapidly becoming the standard of care, especially in patients with previous abdominal surgery and other significant comorbidities. This article describes our experience with AAAs in orthotopic liver transplant recipients treated successfully by endovascular stent graft repair.  相似文献   
52.
Effect of photodynamic therapy on blood flow in normal and tumor vessels   总被引:1,自引:0,他引:1  
The aim of this series of experiments was to determine the dynamic blood flow changes that occur in normal and neoplastic tissues during photodynamic therapy. Mice bearing SMT-F tumors and rats with transplanted chondrosarcomas were injected with graded doses of dihematoporphyrin ether. Studies of changes in single-vessel and whole-tumor blood flow were carried out with 630 nm light activation. A helium neon laser Doppler velocimeter was used to stimulate dihematoporphyrin ether, as well as to measure changes in flow velocity in both single-vessel and whole-tumor models. There was a reduction of flow velocity in all vessels and tumors in animals injected with 1 to 40 mg/kg dihematoporphyrin ether intraperitoneally. The extent of flow reduction was related to drug dose administered. Decreases in blood flow began within 10 seconds of light stimulation and were maximal within 5 minutes. Both normal and tumor vessels responded similarly. We conclude that photodynamic therapy leads to significant microcirculatory changes that may be pertinent to the mechanism of tumor necrosis.  相似文献   
53.
54.
Dendritic cells (DCs) are professional antigen-presenting cells that are specialized in the uptake of antigens and their transport from peripheral tissues to the lymphoid organs. Over the last decades, the properties of DCs have been intensely studied and much knowledge has been gained about the role of DCs in various diseases and health conditions where the immune system is involved, particularly in cancer and autoimmune disorders. Emerging clues in autoimmune diseases, suggest that dendritic cell dysregulation might be involved in the development of various autoimmune disorders in both adults and children. However, studies investigating a possible contribution of DCs in autoimmune diseases in the pediatric population alone are scanty. The purpose of this review is to give a general overview of the current literature on the relevance of dendritic cells in the most common autoimmune conditions of childhood.  相似文献   
55.
Intra-articular synovial chondromatosis in the hand is rare but should be considered in the differential diagnosis of a swollen, stiff or painful joint. Other possible diagnoses include osteoarthritis, rheumatoid arthritis, gout, trauma and chronic infection, and unless enchondral ossification of loose bodies is seen the diagnosis of synovial chondromatosis may not be made preoperatively. A 69-year-old man with synovial chondromatosis of the metacarpophalangeal joint is reported. The joint was swollen and tender. He had not sustained trauma and there was no evidence of arthritis, involvement of other joints or infection. Complete synovectomy with removal of all loose bodies was successful and his symptoms resolved. Intra-articular synovial chondromatosis is a benign condition, but spontaneous resolution is the exception and surgical synovectomy remains the most effective treatment.  相似文献   
56.
Corticobasal degeneration (CBD) is an adult–onset, progressive parkinsonian syndrome with strikingly asymmetrical features, and signs and symptoms referable to both cerebral cortex and basal ganglia. Although once considered rare, it is now recognized with increasing frequency during life. Eight patients with clinically diagnosed CBD and 8 age– and sex–matched patients with Parkinson's disease underwent high–field–strength magnetic resonance imaging (MRI) of the brain. MRIs were graded by a blinded neuroradiologist using a semiquantitative (0–3) scale. MRI of patients with CBD revealed significantly greater T2–weighted signal hypointensity in the putamena and globi pallidi, and ventricular enlargement. When specifically sought, asymmetrical cortical atrophy was identified in 5 of 8 CBD patients. Increased T2–weighted lenticular signal hypointensity, ventricular enlargement, and asymmetrical cortical atrophy are supportive MRI findings of CBD.  相似文献   
57.
Predictors of healthy aging in men with high life expectancies.   总被引:5,自引:0,他引:5       下载免费PDF全文
OBJECTIVE: The purpose of this study was to identify risk factors that consistently predict staying healthy in contrast to developing clinical illness and/or physical and mental impairments. METHODS: More than 8000 men of Japanese ancestry were followed for 28 years with repeat examinations and surveillance for deaths and incident clinical illness. Physical and cognitive functions were measured in 1993. Measures of healthy aging included surviving and remaining free of major chronic illnesses and physical and cognitive impairments. RESULTS: Of 6505 healthy men at baseline, 2524 (39%) died prior to the final exam. Of the 3263 available survivors, 41% remained free of major clinical illnesses, 40% remained free of both physical and cognitive impairment, and 19% remained free of both illness and impairment. The most consistent predictors of healthy aging were low blood pressure, low serum glucose, not smoking cigarettes, and not being obese. CONCLUSIONS: Beyond the biological effects of aging, much of the illness and disability in the elderly is related to risk factors present at midlife.  相似文献   
58.
Although sexual assault by workplace personnel is widely viewed as a type of sexual harassment, little is known about whether these overlapping constructs may possess some unique characteristics. This article compares the theoretical antecedents and consequences of sexual assault by workplace personnel and other types of sexual harassment among 22,372 women employed in the U.S. military. Path analysis revealed that low sociocultural and organizational power are associated with an increased likelihood of both types of victimization. Organizational climate and job gender context are directly associated with sexual harassment but are only indirectly associated with sexual assault by workplace personnel. Both types of victimization are associated with a variety of negative outcomes, but the pattern of negative consequences differs.  相似文献   
59.
The ability of a purified major histocompatibility antigen to serve as the target cell antigen for alloreactive CTL (H-2d anti-H-2k) was examined. Tumor cells syngeneic with responding CTL were used as targets following modification with purified alloantigen (H-2Kk). A short incubation of tumor cells with H-2Kk liposomes followed by the addition of polyethylene glycol (PEG) yielded modified tumor cells that were recognized and lysed by CTL. The macrophage-like cell line P388D1 was readily recognized following liposome and PEG modification; apparently because these cells can withstand PEG mediated insertion of H-2Kk and lipid into their membrane. The generation of targets by PEG mediated modification was most efficient using liposomes prepared with an H-2Kk:lipid ratio of about 1:500. H-2Kk containing liposomes prepared with negatively charged phospholipids readily attached to P388D1 cells, however these cells were not targets for CTL unless PEG was added. The specificity of CTL recognition and lysis of liposome modified cells was shown by the reactivity of CTL primed against alloantigens other than H-2Kk and by antibody (anti-H-2Kk) blocking of recognition and lysis. These results demonstrate that purified H-2Kk can serve as the alloantigen for CTL lysis and suggest that the H-2 must be oriented in the target cell lipid bilayer to serve as the alloantigen for CTL mediated target cell lysis.  相似文献   
60.
Chronic rejection is the major threat to both heart and renal allograft survival. We have explored the possibility that some patients with anti-donor HLA antibodies (Ab1) develop specific anti-idiotypic antibodies (Ab2) which suppress the production of Ab1, and subsequently, the progression of chronic rejection. analysis of Ab2 in sera obtained from Ab1 producers showed that 22% of heart and 18% of kidney recipients produced Ab2. The 4- and 5-year actuarial graft survivals in Ab2 producers were 100% and 83%, respectively, compared to 57% in patients who formed Ab1 but not Ab2 (p<0.004). Patients carrying the DR2 alleles, DRB1*1501,*1502 or*1601 were at a lower risk of producing anti-donor HLA antibodies.  相似文献   
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