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1.
PURPOSE: To evaluate the role of adjuvant interferon alfa after complete resection of locally extensive renal cell carcinoma. PATIENTS AND METHODS: A total of 283 eligible patients with pT3-4a and/or node-positive disease were randomly assigned after radical nephrectomy and lymphadenectomy to observation or to interferon alfa-NL (Wellferon, Burroughs-Wellcome, Research Park, NC) given daily for 5 days every 3 weeks for up to 12 cycles. Patients were stratified on the basis of pathologic stage. Patients remained on treatment until documented recurrence, excessive toxicity, or patient/physician preference deemed removal appropriate. RESULTS: At median follow-up of 10.4 years, median survival was 7.4 years in the observation arm and 5.1 year in the treatment arm (log-rank P =.09). Median recurrence-free survival was 3.0 years in the observation arm and 2.2 years in the interferon arm (P =.33). Performance status (P =.003), nodal status (N2 v N0, P <.0001), and tumor stage (P =.0002) were significant prognostic factors in multivariate analysis. A proportional hazards model examining the effects of treatment arm and time to recurrence on survival after recurrence among patients who recurred found that random assignment to interferon treatment (P =.009) and shorter time to recurrence (P <.0001) were independent predictors of shorter survival after recurrence. Although no lethal toxicities were observed, severe (grade 4) toxicities including neutropenia, myalgia, fatigue, depression, and other neurologic toxicities occurred in 11.4% of those randomly assigned to interferon treatment. CONCLUSION: Adjuvant treatment with interferon did not contribute to survival or relapse-free survival in this group of patients.  相似文献   
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Opioid receptor binding was evaluated in parahippocampal cortex (PHC) obtained from patients with intractable mesial temporal lobe epilepsy (MTLE) with and without subacute high frequency electrical stimulation (HFS) in this brain area. Mu, delta and nociceptin receptor binding was determined by autoradiography in PHC of five patients (ESAE group) with MTLE history of 14.8 +/- 2.5 years and seizure frequency of 11 +/- 2.9 per month, two of them (40%) with mesial sclerosis. This group demonstrated antiepileptic effects following subacute HFS (130 Hz, 450 micros, 200-400 microA), applied continuously during 16-20 days in PHC. Values were compared with those obtained from patients with severe MTLE (history of 21.7 +/- 2.8 years and seizure frequency of 28.2 +/- 14 per month) in whom electrical stimulation did not induce antiepileptic effects (ESWAE group, n = 4), patients with MTLE in whom no electrical stimulation was applied (MTLE group, n = 4) and autopsy material acquired from subjects without epilepsy (n = 4 obtained from three subjects). Enhanced 3H-DAMGO (MTLE, 755%; ESAE, 375%; ESWAE, 693%), 3H-DPDPE (MTLE, 242%; ESAE, 80%; ESWAE, 346%) and 3H-nociceptin (MTLE, 424%; ESAE, 217%; ESWAE, 451%) binding was detected in the PHC of all epileptic groups. However, tissue obtained from ESAE group demonstrated lower opioid receptor binding (3H-DAMGO, 44.5%, p < 0.05; 3H-DPDPE, 47%, p < 0.05; 3H-nociceptin, 39.3%, p < 0.5) when compared with MTLE group. The present results indicate that a high effectiveness to the antiepileptic effects induced by HFS is associated with reduced opioid peptide binding.  相似文献   
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OBJECTIVE: To explore the effects of electrical stimulation performed by an anode, a cathode or a bipole positioned over the motor cortex for chronic pain management. METHODS: A realistic 3D volume conductor model of the human precentral gyrus (motor cortex) was used to calculate the stimulus-induced electrical field. The subsequent response of neural elements in the precentral gyrus and in the anterior wall and lip of the central sulcus was simulated using compartmental neuron models including the axon, soma and dendritic trunk. RESULTS: While neural elements perpendicular to the electrode surface are preferentially excited by anodal stimulation, cathodal stimulation excites those with a direction component parallel to its surface. When stimulating bipolarly, the excitation of neural elements parallel to the bipole axis is additionally facilitated. The polarity of the contact over the precentral gyrus determines the predominant response. Inclusion of the soma-dendritic model generally reduces the excitation threshold as compared to simple axon model. CONCLUSIONS: Electrode polarity and electrode position over the precentral gyrus and central sulcus have a large and distinct influence on the response of cortical neural elements to stimuli. SIGNIFICANCE: Modeling studies like this can help to identify the effects of electrical stimulation on cortical neural tissue, elucidate mechanisms of action and ultimately to optimize the therapy.  相似文献   
5.
A similar imbalance of globin chain synthesis, with low non-alpha/alpha ratios, was shown in peripheral blood and in bone marrow of compound heterozygotes for both the Hb S and beta zero thalassaemia genes (S/beta zero thalassaemia). Previous purification of whole cell globin obtained from the bone marrow did not change the non-alpha/alpha ratio. The mean non-alpha/alpha ratios were 0.57 +/- 0.13 (means +/- SD) for the peripheral blood of 12 patients, 0.52 +/- 0.10 for five patients using bone marrow globin purified on Sephadex G100, and 0.55 +/- 0.16 for the unfiltered bone marrow globin of five patients. The data show that patients with S/beta zero thalassaemia have a similar beta chain deficiency in reticulocytes and in bone marrow cells, provided whole cell globin is used which avoids the removal of the free alpha chains. The non-alpha/alpha ratios in the peripheral blood of an S/beta zero thalassaemia patient and a beta thalassaemia heterozygote from the same family were compared in seven families and no significant difference was found.  相似文献   
6.
Reno LA  Zago W  Markus RP 《Neuroscience》2004,124(3):647-653
This is a neurochemical study which shows that nicotine acting through alpha7-containing nicotinic acetylcholine receptors promotes the release of [(3)H]-glutamate from rat cerebellar slices. Release evoked by half maximal concentration of nicotine (100 microM) was blocked by alpha-bungarotoxin and in a calcium-free medium, suggesting an effect mediated by an alpha7 receptor. Dihydro-beta-erythroidine and mecamylamine were effective only at very high concentrations, excluding the participation of heteromeric receptors. The effect of nicotine was partially blocked by inhibitors of glutamatergic receptors DL-2-amino-5-phosphonovaleric acid and 6-cyano-7-nitroquinoxaline-2,3-dione, indicating a glutamate-induced glutamate release. Nicotine-evoked response was dependent on activation of tetrodotoxin sensitive sodium channels. Therefore, here we show that glutamate released by stimulation of alpha7-containing nicotinic receptors, located preterminal and/or postsynaptically, evokes a further glutamate release in adult rat cerebellar slices.  相似文献   
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PURPOSE: To assess the efficacy of the marine-derived alkaloid ecteinascidin 743 (ET-743) in patients with soft tissue sarcomas that progressed despite prior conventional chemotherapy and to characterize the pharmacokinetic profiles of ET-743 in this patient population. PATIENTS AND METHODS: Thirty-six previously treated soft tissue sarcoma patients from three institutions received ET-743 as a 24-hour continuous intravenous (IV) infusion at a dose of 1,500 microg/m(2) every 3 weeks. Pharmacokinetic studies were also performed. Patients were restaged every two cycles for response by objective criteria. RESULTS: Objective responses were observed in three patients, with one complete response and two partial responses, for an overall response rate of 8% (95% CI, 2% to 23%). Responses were durable for up to 20 months. Two minor responses (43% and 47% tumor reduction) were observed, for an overall clinical benefit rate of 14%. The predominant toxicities were neutropenia and self-limited transaminitis of grade 3 to 4 severity in 34% and 26% of patients, respectively. The estimated 1-year time to progression and overall survival rates were 9% (95% CI, 3% to 27%) and 53% (95% CI, 39% to 73%), respectively. The maximum observed plasma concentration and total plasma clearance of ET-743 (mean +/- standard deviation), 1.04 +/- 0.48 ng/mL and 35.6 +/- 16.2 L/h/m(2), respectively, were consistent with previously reported values from phase I studies of the drug given as a 24-hour IV infusion. CONCLUSION: ET-743 is a promising new option for the management of several histologic subtypes of sarcoma. Durable objective responses were obtained in a subset of sarcoma patients with disease progression despite prior chemotherapy. Additionally, the relatively high survival rate noted in this series of previously treated patients further justifies development of this agent.  相似文献   
9.
PURPOSE: Understanding the distinctive patterns of treatment-related dysfunction after alternative initial treatments for early prostate cancer (PC) may improve patients' choice of treatment and later help them adjust to its consequences. We characterized the time course of treatment complications while adjusting for potentially confounding pretreatment factors hindering other observational studies. PATIENTS AND METHODS: In a prospective cohort study of 417 men we assessed urinary, bowel, and sexual function from before primary treatment to 24 months after. To control for potential confounding, we measured sociodemographic and PC prognostic factors, medical comorbidity, and pretreatment function commonly affected by PC and its treatment. RESULTS: Patients who underwent external beam radiotherapy (EBRT), radical prostatectomy (RP), and brachytherapy (BT) differed significantly in sociodemographic factors, cancer prognostic factors, and pretreatment symptom status, especially sexual function. Urinary incontinence increased sharply after RP, while bowel problems and urinary irritation/obstruction rose after EBRT and BT. Sexual dysfunction increased in all patients, particularly after radical prostatectomy, and nerve-sparing surgical technique had little apparent benefit. There was no change in urinary function and little change in overall bowel function after 12 months, but the time course of sexual dysfunction varied by treatment and, for bowel function, by symptom. Multiple regression modeling confirmed that treatment influences all 24-month outcomes, but residual confounding persisted. CONCLUSION: Pretreatment function and the primary treatment modality for early stage PC strongly predict the affected organ systems and time course of dysfunction. With this information, patients and their physicians may refine their choice of treatment and better anticipate its consequences.  相似文献   
10.
Hb F levels were determined on samples from 750 normal blood donors. Six individuals (0.8%) had Hb F levels in excess of 1.1%, the upper end of the continuous distribution. Eight individuals at the upper end and 7 individuals at the lower end of the range were selected for family studies. These studies revealed that the control of Hb F levels in adults, as judged by the more sensitive F-cell technique, has a major genetic component. Structural analysis of the Hb F in several cases demonstrated that both G gamma and A gamma chains were present, but in variable proportions. These results are discussed in light of current concepts of adult F-cell production.  相似文献   
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