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91.
92.
DR Vlock SP Schantz SG Fisher HE Savage TE Carey GT Wolf 《Canadian Metallurgical Quarterly》1993,11(12):2427-2433
PURPOSE: To evaluate the correlation between the presence and titer of host-derived antibody reactivity, circulating immune complexes, and clinical course and prognosis in patients with squamous cell carcinoma of the head and neck (SCCHN). MATERIALS AND METHODS: Serum samples, obtained from untreated patients with squamous cell carcinoma of the larynx entered onto a multiinstitutional trial, were evaluated for the presence of elevated circulating immune complexes (221 patients) and host-derived antibody directed against two SCCHN cell lines (107 patients). RESULTS: Patients had significantly elevated levels of circulating immune complexes as measured by C1q binding compared with normal controls. Patients with higher levels of circulating immune complexes were less likely to respond to chemotherapy. No correlations were noted between immune complex levels and stage of disease, nodal status, site of disease, recurrence, or survival. Evaluation of native antibody titers for their relationship to clinical correlates showed no statistically significant associations. In sera subjected to immune complex dissociation, patients with moderately or poorly differentiated tumors had significantly higher antibody titers when compared with patients with well-differentiated tumors. Because marked variation in the increase of antibody titers following immune complex dissociation was noted, the ratio of immune complex-dissociated to native antibody titer was examined. Patients with a high ratio had a lower proportion of complete and partial responses to chemotherapy. CONCLUSION: Our results support the conclusion that the formation of tumor-associated immune complexes in patients with SCCHN is associated with a decreased response to chemotherapy. 相似文献
93.
VK Il''in KG Apostolidi VN Filatov VV Ryl''tsev AA Belov TE Ignatiuk 《Canadian Metallurgical Quarterly》1994,134(2):42-43
In December 1991, an outbreak of Streptococcus bovis septicaemia occurred in a Belgian pigeon loft where 25 male and 25 female racing pigeons were housed. The main clinical signs included inability to fly and poor breeding results. None of the female pigeons and only one male pigeon was able to fly. Nine affected pigeons were necropsied. Histologically a tenosynovitis of the tendon of the deep pectoral muscle was observed in most of them and S bovis was isolated from the canalis triosseus or the shoulder joints of five of the nine pigeons. The pigeons were successfully treated with ampicillin administered in the drinking water for seven days. 相似文献
94.
95.
This article reviews pharmacologic approaches to treating acute respiratory distress syndrome (ARDS). The authors discuss the therapeutic effects of ketoconazole, antioxidants, corticosteroids, surfactant, ketanserin, pentoxifylline, bronchodilators, and almitrine in ARDS. Current animal data and proposed mechanics which may foster future pharmacologic therapies are also examined. 相似文献
96.
K Saatvedt H Lindberg OR Geiran S Michelsen T Pedersen E Seem TE Mollnes 《Canadian Metallurgical Quarterly》1996,31(4):596-602
OBJECTIVES: The purpose of the study was to evaluate the clinical and hemodynamic effect of intraoperative extracorporeal ultrafiltration (UF) and its potential in reducing the plasma concentration of circulating cytokines and complement activation products following open heart surgery in children. METHODS: Eighteen children with congenital heart disease were prospectively randomized into a control group (n = 9) and a group who underwent UF (n = 9). Serial plasma samples for measurements of circulating cytokines (interleukin 6 (IL-6), tumor necrosis factor alpha (TNF), and its soluble receptor (sTNF receptor)), and complement factors (C3 activation products (C3a and C3bc) and terminal complement complex (TCC)) were obtained before, during and up to 48 h after cardiopulmonary bypass (CPB). A pulmonary artery thermodilution catheter was introduced preoperatively for hemodynamic monitoring. RESULTS: Postoperative hemodynamics were similar in both groups. Plasma levels of IL-6, sTNF receptors, C3a, C3bc and TCC increased significantly perioperatively (P < 0.01) in both groups. TNF was detected transiently in 16 patients perioperatively and in 4 of the 9 ultrafiltrate samples in concentrations similar to the plasma levels. Complement activating products were not detected in the ultrafiltration samples except for small amounts of C3a in two cases. Compared to the control group the plasma levels of C3a, C3bc and TCC were unaffected by the ultrafiltration procedure. The level of IL-6 and sTNF receptors increased significantly after 15 min of UF but there was no significant difference between the two groups postoperatively. CONCLUSIONS: In this study no clinical or hemodynamic effect was registered after UF. TNF and C3a were occasionally detected in the ultrafiltrate but we were unable to demonstrate reduction of these or any of the other markers tested in the group subjected to ultrafiltration. 相似文献
97.
Idiopathic thrombocytopenic purpura (ITP) is refractory to initial treatment (steroids and splenectomy) in 25 to 30% of patients. These patients have a significant risk of fatal hemorrhage. Two patients with ITP refractory to multiple interventions and severe depression of platelet counts responded to treatment with liposomal doxorubicin with a return of platelet counts to normal. The drug is easily administered and was well tolerated. Use of this drug in refractory ITP merits further study. 相似文献
98.
DM Brienza KC Chung CE Brubaker J Wang TE Karg CT Lin 《Canadian Metallurgical Quarterly》1996,4(2):103-113
Chronic aspiration in the neurologically impaired child is associated with significant medical and social complications. Traditional surgical management has often relied on tracheotomy. This may well fail to control aspiration. The purpose of this retrospective study was to determine which neurologically impaired children would benefit from a laryngotracheal separation (LTS), as opposed to tracheotomy, as the primary surgical procedure to control chronic salivary aspiration. Patient selection was based on neurologic status, verbal communication ability, likelihood of neurologic recovery, and failure of previous treatments to control aspiration. Nineteen neurologically impaired children aged 8-172 months with chronic salivary aspiration underwent LTS. A total of 73.6% of these patients had prior tracheotomies, yet they continued to aspirate. Two early and three late complications were noted. No instances of fistula formation were noted. There were no deaths related to complications of the surgery or persistent aspiration. Follow-up 1-62 months after surgery demonstrated that complete control of the aspiration was achieved in all of these children. Two of the children who had achieved verbal communication prior to the procedure lost this ability. Improved general health and ability to resume oral intake was noted in all patients. This, combined with a decrease in the need of frequent suctioning, was felt by the families of these children to be a major improvement in the quality of life. Laryngotracheal separation appears to be a simple and effective means of controlling chronic aspiration. It should be considered as a primary treatment of aspiration in the properly selected child with neurologic disease. 相似文献
99.
100.
Measurement of rapid renal hemodynamic changes were made for 90 s in pentobarbital-anesthetized dogs following step increases and decreases in renal arterial pressure between 80 and 120 mm Hg. Transient analysis was used to observe time characteristics of the autoregulatory relationships which are obscured in steadystate measurements. Temporal decoupling of blood flow and glomerular filtration rate (GFR) occurred with both step increases and decreases of arterial pressure. Steady-state autoregulation of blood flow was attained in about 30 s, whereas steady-state autoregulation of GFR was not demonstrably attained even 90 s after the arterial pressure maneuver. The temporal decoupling of renal blood flow and GRR supports the concept of transient involvement of proximal tubular dynamics and efferent resistance changes during acute autoregulation of GFR following step changes in arterial pressure. 相似文献