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81.
82.
Polymorphonuclear leukocyte elastase activity is increased by bacterial lipopolysaccharide: a response inhibited by glucocorticoids 总被引:6,自引:0,他引:6
Human neutrophil elastase is thought to play an important role in connective tissue destruction in diseases such as emphysema and arthritis. In this article, it is demonstrated that the elastase activity of mature human peripheral blood neutrophils can be rapidly increased in vitro by treatment of the cells with lipopolysaccharide from E. coli and that this increase is inhibited by corticosteroid pretreatment of the cells and by inhibitors of protein synthesis. Alterations in intracellular enzyme content of the mature polymorph in response to bacterial products or other stimuli may be important for amplification of the inflammatory response. 相似文献
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84.
The cost of autologous transfusions using semiautomated instruments in 52 orthopedic cases, 75 coronary artery bypass graft (CABG) cases, and 218 aortic aneurysm cases was compared to the cost of equal amounts of homologous blood. While none of the orthopedic cases reached cost equivalence (median cost deficit per case, +97), 31 percent of the CABG cases (median cost deficit per case, +61) and 56 percent of the thoracic aortic aneurysm cases (mean cost surplus per case, +30) did so. In most cases, the major orthopedic and CABG procedures do not reach cost equivalence and might be served better by other means of autologous blood recovery. The more expensive semicontinuous flow devices are more cost-effective for higher-yield cases, such as major aortic aneurysm procedures. 相似文献
85.
Ovarian metastases: computed tomographic appearances 总被引:4,自引:0,他引:4
Computed tomographic scans of 34 patients with ovarian metastases were reviewed to assess the radiographic appearances and to correlate these with the primary neoplasms. Primary neoplasms were located in the colon (20 patients), breast (six), stomach (five), small bowel (one), bladder (one), and Wilms tumor of the kidney (one). The radiographic appearance of the metastatic lesions could be described as predominantly cystic (14 lesions), mixed (12 lesions), or solid (seven lesions). There was one false-negative examination which showed no ovarian enlargement, although neoplastic deposits were found on the ovary at laparotomy. The cystic and mixed lesions tended to be larger in overall diameter than the solid. The metastases from gastric carcinoma appeared solid in four of five cases. The metastases from the other neoplasms had variable appearances simulating primary ovarian carcinoma. 相似文献
86.
A modified zymosan preparation was used to probe the interaction of particulate stimuli with human neutrophils (PMNs). After extraction with alkali and detergent, the zymosan particles retained their ability to be opsonized in serum and to stimulate PMNs. Serum-treated zymosan (STZ) induced dose-dependent superoxide (O2-) production and membrane potential depolarization in the range of 1 to 10 mg/mL of STZ. The rate and extent of secretion of lysozyme and beta-glucuronidase were also dose-dependent in the range of 1 to 10 mg/mL of STZ. Cytochemical studies using nitroblue tetrazolium, however, showed that 92% of PMNs were stimulated to produce O2- at 0.1 mg/mL of STZ. The dose response of O2- production induced by STZ is therefore due to increasing O2- production by individual PMNs and not to the stimulation of more PMNs to produce O2-. Evidence for O2- production was found only in the area of PMN-zymosan contact, suggesting a mechanism for the graded responses of PMNs treated with particulate stimuli. In order to determine the nature of the dose dependence of depolarization (a measure of PMN activation), PMNs equilibrated with the fluorescent probe 3,3'- dipentyloxacarbocyanine were analyzed by flow cytometry. The results demonstrate that STZ induces a dose-dependent depolarization of the membrane potential of individual PMNs. These results also demonstrate that increasing concentrations of STZ can induce increasing PMN responses even when all of the PMNs have been activated. These results are consistent with the hypothesis that receptor-mediated particulate stimulation of PMNs is a phenomenon that results in graded PMN responses. 相似文献
87.
Angiography of upper extremity access fistulas for dialysis 总被引:4,自引:0,他引:4
One-hundred twenty-five cases of upper extremity internal arteriovenous and graft fistulas were reviewed. Clinical problems requiring study were poor fistula flow during dialysis, difficulty in cannulation, diminished graft pulsations, extremity edema or varicosities, the appearance of pulsatile or nonpulsatile masses in the graft or fistula, and distal ischemia. Angiography demonstrated venous occlusion (13 cases), venous stenosis at or near the anastomotic site (32 cases), thrombi within shunts (9 cases), venous aneurysms or pseudoaneurysms related to either proximal obstruction or traumatic dialysis (23 cases), distal venous overdistention due to proximal obstruction or overcirculation (15 cases), and radial artery steal of blood from the distal extremity (15 cases). The causes and predisposing factors leading to the complications are presented along with a discussion of the angiographic techniques that were used. 相似文献
88.
M Reynard C Wertenbaker M Behrens R Lesser H Eggers J Ilson J Mitchell C Bever 《Neurology》1979,29(5):757-758
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90.