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PURPOSE: The purpose of this study was to determine whether amifostine (WR-2721) prevents or ameliorates clinically significant (grade 2 to 4) neurotoxicity associated with cisplatin and 3-hour paclitaxel chemotherapy.Materials and METHODS: The chemotherapy program consisted of intravenous paclitaxel 175 mg/m2 over 3 hours followed by amifostine 740 mg/m2 and cisplatin 75 mg/m2 administered over 90 minutes beginning 15 minutes after amifostine administration. At baseline, before each treatment cycle, and for 3 months after completing chemotherapy, patients were evaluated for evidence of neurotoxicity and other treatment-related adverse effects using three methods: standard clinical evaluation (National Cancer Institute common toxicity criteria [CTC] grading), a neurotoxicity questionnaire to assess symptoms and limitations imposed by peripheral neuropathy, and vibration perception threshold (VPT) testing. RESULTS: Four of 27 assessable patients developed grade 2 to 4 neurotoxicity based on clinical assessments and CTC grading. This number of neuropathic events exceeded the predetermined threshold level for a second stage of accrual and the study was closed. CONCLUSION: Amifostine's level of activity in this trial was insufficient to warrant further study in a phase III trial. Based on the receiver operating characteristic analysis, it would appear that VPT measurements are less sensitive to the development of peripheral neuropathy than the neurotoxicity questionnaire. The questionnaire, referred to as the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity, may be used instead of VPT measurements in future studies of chemotherapy-induced peripheral neuropathy.  相似文献   
73.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
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Alcohol abuse is associated with increases in both the incidence of fractures and complications in fracture healing. The purpose of this study was to determine the dose-dependent effects of ethanol on bone repair in a rat model. Three-month-old male Wistar rats were continuously fed liquid diets containing ethanol as either 36% or 26% of total calories or control diets for 6 weeks. Then, a bone repair model was created in all rats. Bone healing and liver metabolism were evaluated 7 weeks after bone injury. For each dose, there were three ethanol-feeding groups receiving (1) ethanol for 13 weeks, (2) control diet for 13 weeks (pair-fed), and (3) ethanol before bone injury and control diet (pair-fed) after injury. Another group was fed ethanol (36%) before injury and given control diet ad libitum after injury. There were also two nutritional controls consuming control diet and standard rat chow ad libitum for 13 weeks. Abnormal liver metabolism was evident at the higher ethanol dose - increases in cytochrome P4502E1 specific activity (5-fold; P < .01), triglyceride content (4-fold; P < .02), and liver weight (25%; P = .05) - compared with pair-fed controls. The higher dose of ethanol resulted in deficient bone repair when compared with rats receiving ethanol-free control diet by pair-feeding: 26% less (P = .02) rigidity of the repaired bone, 41% less (P = .02) intrinsic stiffness, 24% less intrinsic strength (P = .05), and 14% less (P = .001) ash density of the repair tissue. The reduced food consumption of ethanol-fed rats compared with that in the nutritional controls did not contribute to this deficiency. Furthermore, removal of ethanol (as 36% of calories) from the diet after bone injury completely restored normal bone healing and nearly normalized the liver metabolism. The lower ethanol dose (26% of calories) had a minimal effect on liver metabolism and bone repair. We conclude that ethanol (as 36% of calories) in the rat diet, especially during the postinjury period, was solely responsible for the observed inhibition of bone repair.  相似文献   
75.
Dopamine-replacement strategies form the basis of most symptomatic treatments for Parkinson's disease. However, since long-term dopamine-replacement therapies are characterized by many side effects, most notably dyskinesia, the concept of a nondopaminergic therapy for Parkinson's disease has attracted great interest. To date, it has proved difficult to devise a nondopaminergic therapy with efficacy comparable to that of dopamine replacement. In animal models of Parkinson's disease, loss of striatal dopamine leads to enhanced excitation of striatal NR2B-containing NMDA receptors. This is responsible, in part at least, for generating parkinsonian symptoms. Here we demonstrate that, in the MPTP-lesioned marmoset, monotherapy with the NR2B-selective NMDA receptor antagonist, ifenprodil, administered de novo, has antiparkinsonian effects equivalent to those of l-DOPA (administered as its methyl ester form). In MPTP-lesioned marmosets, median mobility scores, following vehicle-treatment were 12.5/h (range 6-21), compared to 61/h (range 26-121) in normal, non-MPTP-lesioned animals. Following ifenprodil (10 mg/kg) treatment in MPTP-lesioned marmosets, the median mobility score was 66/h (range 34-93), and following l-DOPA (10 mg/kg i.p.) treatment 89/h (range 82-92). The data support the proposal that NR2B-selective NMDA receptor antagonists have potential as a nondopaminergic monotherapy for the treatment of parkinsonian symptoms when given de novo.  相似文献   
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OBJECTIVE: The effectiveness of a community-based case management program at the Veterans Affairs West Los Angeles Healthcare Center in reducing hospital readmission of mentally ill veterans living in privately operated board-and-care homes was evaluated. METHODS: A retrospective cohort design was used. The sample consisted of 321 patients identified by hospital records as living in one of 24 board-and-care homes in the Los Angeles area that were approved by the community residential care program. A total of 214 subjects who received monthly home visits from case managers (program group) were compared with 107 subjects who did not receive monthly home visits (comparison group). The median number of psychiatric bed-days used was calculated for the two years before and after follow-up. The number of days from the start of follow-up to the first psychiatric hospitalization was also calculated. RESULTS: Among subjects in the program group, the median number of psychiatric bed-days used decreased significantly, from 59 days to 50 days. No significant change in the median number was observed for comparison subjects. Comparison subjects were rehospitalized 1.7 times more often than program subjects. Overall, program subjects under age 62 (younger subjects) were rehospitalized 2.5 times more often than older subjects. In the program group, those who had received home visits for more than two years were hospitalized three times more often than those who had received visits for less than two years, and younger subjects were rehospitalized 1.8 times more often than older subjects. CONCLUSIONS: The findings suggest that home visits conducted by case managers in a community residential care program helped reduce psychiatric hospitalization among veteran patients living in privately operated board-and-care homes.  相似文献   
78.
Lexical retrieval during fluent speech production: an fMRI study   总被引:1,自引:0,他引:1  
We investigated the neural correlates of lexical retrieval during fluent speech production using fMRI. Blood oxygenation level dependent (BOLD) contrast was measured while subjects spoke about 7 Rorschach inkblots for 3 min each. Varying degrees of speech rate were elicited during each run. In a within-subject design, the number of words produced was correlated with the BOLD contrast in the two runs in each subject that showed the highest variance of speech output. The rate of articulation was positively correlated with activation in the left superior temporal (BA 22) and supramarginal (BA 39/ 40) gyri. The main negative correlations were in the fusiform gyri bilaterally (BA 19), the posterior cingulate (BA 30) and superior occipital gyrus (BA 19). Lexical retrieval during continuous language production engages areas in the left temporal and inferior parietal cortex. This pattern of activation differs from that evident during the generation of single words (verbal fluency), which is more associated with left prefrontal activation.  相似文献   
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