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BACKGROUND: Whether or not tumor response to chemotherapy-sensitized radiation therapy (CTRT) for head and neck cancer leads to an improved outcome is unknown. METHODS: Forty patients who received preoperative cisplatin plus simultaneous radiotherapy for operable stage III and IV head and neck cancer were reviewed retrospectively regarding clinical demographics, staging, and survival status. RESULTS: Twenty-one (57%) patients had a histologic complete response (HCR) and 16 (43%) had a partial (PR) (9) or clinical complete (7) response (CCR). Tumor response of N1 versus N2-3 nodal disease showed 6 (75%) HCR and 4 (25%). Five-year disease-free survival overall was 82% for HCR versus 38% for PR/CCR (P <0.05). Disease-specific 5-year survival was 100% for HCR versus 27% for PR/CCR (P <0.002). CONCLUSIONS: Histologic complete response to CTRT for head and neck cancer is associated with increased survival and encouraging disease-free status. Response to CTRT is inversely proportional to lymphatic tumor load. 相似文献
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Significant spinal deformity is particularly common in nonambulatory patients with myelodysplasia. Progressive deformity may be caused by congenital anomalies, paralytic collapse, hip contractures, or spinal cord tethering. Existing or projected functional impairment should be the principle indication for treatment. Surgical treatment is complicated by poor soft tissue coverage, associated contractures, lack of sensation, weak bone, and absence of posterior elements. Successful fusion can be achieved by circumferential (anterior and posterior) fusion and current rigid segmental instrumentation. The unique deformities and bony anatomy require individualized techniques to achieve fixation. 相似文献
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LA Smith DE Barker CW Chase LB Somberg WB Brock RP Burns 《Canadian Metallurgical Quarterly》1997,63(12):1102-7; discussion 1107-8
The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved. 相似文献
106.
Significant cleavage by hammerhead ribozymes requires activation by divalent metal ions. Several models have been proposed to account for the influence of metal ions on hammerhead activity. A number of recent papers have presented data that have been interpreted as supporting a one-metal-hydroxide-ion mechanism. In addition, a solvent deuterium isotope effect has been taken as evidence against a proton transfer in the rate-limiting step of the cleavage reaction. We propose that these data are more easily explained by a two-metal-ion mechanism that does not involve a metal hydroxide, but does involve a proton transfer in the rate-limiting step. 相似文献
107.
HP Selker JR Beshansky JL Griffith TP Aufderheide DS Ballin SA Bernard SG Crespo JA Feldman SS Fish WB Gibler DA Kiez RA McNutt AW Moulton JP Ornato PJ Podrid JH Pope DN Salem MR Sayre RH Woolard 《Canadian Metallurgical Quarterly》1998,129(11):845-855
BACKGROUND: Approximately 6 million U.S. patients present to emergency departments annually with symptoms suggesting acute cardiac ischemia. Triage decisions for these patients are important but remain difficult. OBJECTIVE: To test whether computerized prediction of the probability of acute ischemia, used with electrocardiography, improves the accuracy of triage decisions. DESIGN: Controlled clinical trial. SETTING: 10 hospital emergency departments in the midwestern, southeastern, and northeastern United States. PATIENTS: 10689 patients with chest pain or other symptoms suggestive of acute cardiac ischemia. INTERVENTION: The probability of acute ischemia predicted by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), either automatically printed or not printed on patients' electrocardiograms. MEASUREMENTS: Emergency department triage to a coronary care unit (CCU), telemetry unit, ward, or home. Other measurements were the bed capacity of the CCU relative to that of the telemetry unit; training or supervision status of the triaging physician; and patient diagnoses and outcomes based on clinical, electrocardiographic, and creatine kinase data. RESULTS: For patients without cardiac ischemia, in hospitals with high-capacity CCUs and relatively low-capacity cardiac telemetry units, use of ACI-TIPI was associated with a reduction in CCU admissions from 15% to 12%, a change of -16% (95% CI, -30% to 0%), and an increase in emergency department discharges to home from 49% to 52%, a change of 6% (CI, 0% to 14%; overall P=0.09). Across all hospitals, for patients evaluated by unsupervised residents, use of ACI-TIPI was associated with a reduction in CCU admissions from 14% to 10%, a change of -32% (CI, -55% to 3%); a reduction in telemetry unit admissions from 39% to 31%, a change of -20% (CI, -34% to -2%); and an increase in discharges to home from 45% to 56%, a change of 25% (CI, 8% to 45%; overall P=0.008). Among patients with stable angina, in hospitals with high-capacity CCUs, use of ACI-TIPI was associated with a reduction in CCU admissions from 26% to 13%, a change of -50% (CI, -70% to -17%), and an increase in discharges to home from 20% to 22%, a change of 10% (CI, -29% to 71%; overall P=0.02). At hospitals with high-capacity telemetry units, use of ACI-TIPI was associated with a reduction in telemetry unit admissions from 68% to 59%, a change of -14% (CI, -27% to 1%), and an increase in emergency department discharges to home from 10% to 21%, a change of 100% (CI, 22% to 230%; overall P=0.02). Among patients with acute myocardial infarction or unstable angina, use of ACI-TIPI did not change appropriate admission (96%) to the CCU or telemetry unit at hospitals with high-capacity CCUs or telemetry units. CONCLUSIONS: Use of ACI-TIPI was associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. This result varied as expected according to the CCU and cardiac telemetry unit capacities and physician supervision at individual hospitals. Appropriate admission for unstable angina or acute infarction was not affected. If ACI-TIPI is used widely in the United States, its potential incremental impact may be more than 200000 fewer unnecessary hospitalizations and more than 100000 fewer unnecessary CCU admissions. 相似文献
108.
WB van den Berg 《Canadian Metallurgical Quarterly》1998,20(1-2):149-164
Chronic arthritis is characterized by a persistent joint inflammation and concomitant joint destruction. Although the joint swelling is a major clinical problem, destruction of bone and cartilage may occur uncoupled to inflammation and it is of utmost importance to fully understand the elements of the destructive process. TNF and IL-1 are considered master cytokines in the process of human RA, with a claimed cascade of TNF inducing most of the IL-1 production. Studies in experimental models revealed that TNF is indeed a pivotal cytokine in joint swelling, yet IL-1 is the dominant cartilage destructive cytokine and its production may occur independent of TNF. This was found with anti-TNF/IL-1 neutralizing antibodies and the observations were recently backed up with similar data in arthritis models in TNF and IL-1 knockout mice. Apart from the absolute level of IL-1, the destructive potential of an arthritis is determined by the balance with regulatory cytokines and anabolic growth factors. IL-4, IL-6, and IL-10 can promote inflammation and tissue fibrosis, yet cartilage destruction is found to be greatly reduced by these cytokines, linked to a range of pathways which can reduce the IL-1 impact on the articular cartilage. Finally, the presence of anabolic growth factors in the inflamed synovium may have a major impact on net destruction. Endogenous transforming growth factor-beta (TGF-beta) is found in inflamed synovia, but local coadministration of TGF-beta further enhanced the degree of synovitis, yet almost fully prevented cartilage damage, providing another example of a major lack of correlation between inflammatory mass and destructive potential. It is suggested that novel therapy in RA patients should not only focus on reduction of outer signs of joint inflammation, but should also include attempts at reduction of cartilage destruction. 相似文献
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