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81.
82.
Carcinoma of the large bowel is the second leading cause of cancer mortality in Singapore. Although the great majority of patients are discovered at a stage where resection with curative intent is possible, almost half of the patients afflicted will die of it. The combination of 5-fluorouracil + levamisole used in patients with curatively resected high risk Dukes B2 and all Dukes' C colon cancers has been shown to reduce cancer recurrence rate and improve overall survival. Since 1990 adjuvant chemotherapy has been recommended for this group of patients. This report describes patients treated in Singapore, their toxicities and their outcome. A total of 341 patients were treated between 1990 and 1996. Treatment compliance was 71.8%. Toxicity was moderate with mainly grade 1-2 nausea and vomiting, diarrhoea, stomatitis, alopecia, and neutropenia. There was 1 treatment-related death. Median recurrence-free interval was 81 months and median survival was not reached at 90 months. This regimen is tolerable. Until further randomised reports comparing 5-fluorouracil + levamisole to other combinations are available, this combination chemotherapy is recommended to patients after surgical resection of the high risk Dukes' B2 and Dukes' C colon cancer to reduce cancer recurrence and improve overall survival.  相似文献   
83.
PURPOSE: We compared gastrointestinal toxicity of single vs. fractionated total body irradiation (TBI) administered at dose rates ranging from 0.021 to 0.75 Gy/min in a canine model of marrow transplantation. METHODS AND MATERIALS: Dogs were given otherwise marrow-lethal single or fractionated TBI from dual 60Co sources at total doses ranging from 8-18 Gy and delivered at dose rates of 0.021, 0.05, 0.10, 0.20, 0.40, and 0.75 Gy/min, respectively. They were protected from marrow death by infusion of previously stored autologous marrow cells and they were given intensive supportive care posttransplant. The study endpoint was 10-day mortality from gastrointestinal toxicity. Logistic regression analyses were used to jointly evaluate the effects of dose rate, total dose, and delivery regimen on toxicity. RESULTS AND CONCLUSION: With increasing dose rates, mortality increased for either mode of delivery of TBI. With dose rates through 0.10 Gy/min, mortality among dogs given single vs. fractionated TBI appeared comparable. Beginning at 0.20 Gy/min, fractionation appeared protective for the gastrointestinal tract. Results in dogs given TBI at 0.40 and 0.75 Gy/min, respectively, were comparable, and dose fractionation permitted the administration of considerably higher total doses of TBI than were possible after single doses, an increment that was on the order of 4.00 Gy. The data indicate that the impact of fractionating the total dose at high dose rates differs from the effect of fractionation at low dose rates.  相似文献   
84.
PURPOSE: To systematically review the methodology and use of neuropsychological tests in randomized controlled trials (RCTs) of antiepileptic drugs (AEDs) in patients with epilepsy. METHODS: Trial reports were found by searching Medline 1966-1996 and searching through journals by hand. Inclusion and exclusion criteria were applied, and methodological and neuropsychological test data was extracted by using a proforma. RESULTS: 43 reports met our inclusion criteria, representing 40 RCTs. as three RCTs had generated two reports. Twenty-two were actively controlled, and 18 were placebo-controlled studies. Reporting of basic methods such as randomization method was poor. There has been no uniform approach to the use of neuropsychological tests, and a total of 87 has been used. The Stroop Colour Word Test and the Finger Tapping Test were most commonly used, at 13 times each, but were not used or reported in a uniform manner. CONCLUSIONS: Poor reporting of methods and the use of a plethora of neuropsychological tests create great difficulties for anyone wishing to make sense of currently available data. If we are better to understand the neuropsychological effects of AEDs, a more rational approach is needed, for which recommendations are made.  相似文献   
85.
The portal hypotensive effects of prazosin and DL-028 (chem- ical name: 3-[[4-(2-methoxyphenyl)piperazin-1-yl]methyl]- 2, 3-dihydroimidazo[1,2-c]quinazolin-5(6H)-one(27b)), a synthetic alpha1-adrenoceptor antagonist, were assessed in portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation in Sprague-Dawley rats. Two weeks after ligation, when the hyperdynamic state was stabilized the rats were anesthetized after an overnight fast and cannulated for measuring mean arterial pressure (MAP), portal venous pressure (PVP), cardiac index (CI) and heart rate (HR). Both DL-028 and prazosin (1, 3.3 and 10 microgram/kg) induced dose-dependent decreases of PVP and MAP after intravenous infusion, with effects lasting for longer than 30 min. The maximum percentage reduction of PVP after DL-028 was 10, 10 and 15%, respectively, for the dosages given (1, 3.3 and 10 microgram/kg), and 5, 12 and 25%, respectively, after prazosin. CI was not changed by either drug. HR was not changed by either drug except DL-028 at 10.0 microgram/kg with a bradycardiac effect. Our results showed that both DL-028 and prazosin reduced PVP in portal hypertensive rats.  相似文献   
86.
CHEB [5-(2-cyclohexylidene-ethyl)-5-ethyl barbituric acid] is a potent convulsant barbiturate that causes direct neuronal excitation by an unknown mechanism. We have analyzed the effects of CHEB on the release of endogenous glutamate from rat cerebrocortical synaptosomes using an on-line enzyme-coupled fluorimetric assay. CHEB evoked spontaneous Ca(2+)-dependent glutamate release with an EC50 = 14.2 microM and an Emax = 3.2 mumol/min/mg. The non-convulsant barbiturates pentobarbital and phenobarbital evoked significantly less glutamate release at high concentrations. CHEB (30 microM) increased intrasynaptosomal [Ca2+] by 58 +/- 4 nM (p < 0.01; n = 4) above baseline compared to an increase of 5 +/- 4 nM (NS; n = 4) produced by pentobarbital (30 microM). CHEB-evoked glutamate release was inhibited by pentobarbital, phenobarbital, EGTA, CoCl2/CdCl2 and flunarizine, but not by local anesthetics, tetrodotoxin, nitrendipine or omega-conotoxin GVIA. These results demonstrate that CHEB acts as a potent and effective secretogogue for glutamate by a pre-synaptic mechanism that does not require activation of Na+ channels or of L-type or N-type Ca2+ channels. Stimulation of spontaneous glutamate release may contribute to the convulsant properties of CHEB.  相似文献   
87.
An innovative treatment is described for unstable total hip arthroplasty that uses a large inside diameter acetabular cup and a bipolar femoral head sized to approximate the diameter of the normal hip. Eight consecutive patients with recurrent prosthetic dislocations were treated with this tripolar hip. Joint stability was achieved in all patients, who have an average of 4.2-years' followup (range, 2.6-6.3 years).  相似文献   
88.
We examined the possibility of an association between the bacterial genotype of Escherichia coli O157:H7 and the likelihood of progression to neurological complications in childhood gastroenteritis-associated haemolytic uraemic syndrome (D+HUS). Bacterial stool isolates were available from 51 patients with HUS; 11 of these patients suffered a neurological complication. Bacteria were assessed for plasmid content, verotoxin (Shiga-like toxin) profile, verotoxin 2 subtype, and presence of the eaeA (effacement and attachment) marker. No association of bacterial genotype with central nervous system (CNS) manifestations was observed. Whilst the cause of CNS manifestations may be multifactorial, there is no evidence at present to implicate specific bacterial traits.  相似文献   
89.
90.
FC Wei  HC Chen  CC Chuang  SH Chen 《Canadian Metallurgical Quarterly》1994,93(2):345-51; discussion 352-7
Microsurgical toe transfer is an established method for reconstruction of missing thumbs. However, there is little agreement on which of the various techniques represents the ideal transfer. Basically, selection of technique requires balancing the patient's functional needs, appearance of the reconstructed thumb, and donor-site cosmesis. Based on our experience with 103 toe-to-thumb transfers performed over the past 9 years, this paper attempts to provide guidelines for appropriate selection among the four most commonly employed toe transfer techniques (e.g., second toe, total great toe, great toe wrap-around, trimmed great toe) so that optimal results and patient's acceptance can both be achieved.  相似文献   
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