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991.
Using liposomes radiolabelled by the 99mTechnetium-stannous chloride technique we have investigated the effect of surface charge on the stability of the isotope in vitro and in vivo. Dialysis of 99mTc-labelled positive, negative and neutral liposomes, which had been incubated in either saline or normal rat serum showed no significant loss of the isotope from the liposome surface with only 2 per cent of the isotope dialysed. A comparison of gel chromatography with dialysis confirmed that most of the isotope remained attached to the liposome surface, but it did reveal greater loss of the isotope, between 15 and 23 per cent. The liposome clearance rates obtained from 125I-egg phosphatidylcholine (EPC) and 99mTc dual-labelled positive or neutral liposomes were significantly different. The 99mTc marker was cleared five times faster from the positive liposomes and twice as fast from the neutral liposomes as the 125I-EPC integral membrane marker. The 99mTc attached to liposomes with a negative surface charge was stable in vivo and had the same clearance rate from the circulation as the 125I-EPC marker. These results indicate that the commonly used in vitro techniques for assessing liposome radiolabel stability are unsuitable for predicting the stability of the 99mTc in vivo.  相似文献   
992.
The syndrome of Maffucci is characterized by angioma association of the enchondromatose. It is a relatively rare syndrome. The lesions are evolutived. The treatment is surgical. His pronostic is marqued by high percentage of malign degenerescence.  相似文献   
993.
994.
Preliminary data suggest that lactitol (beta-galactoside-sorbitol), a new synthetic non-absorbable disaccharide, has beneficial effects on chronic portal systemic encephalopathy. To compare the efficacy of lactitol vs. lactulose in the treatment of acute portal systemic encephalopathy (PSE), 40 cirrhotic patients with an acute episode of PSE were randomly allocated to one of two groups: group A (20 patients) received lactulose (30 ml/6 h) and group B (20 patients) lactitol (12 g/6 h). These doses were adjusted daily to obtain two bowel movements per day. The duration of treatment was 5 days. Age, sex, hepatic and renal function, precipitating factors and level of PSE measured by clinical examination, EEG and number connection test were similar in the two groups. A complete clinical resolution of PSE occurred in 11 patients in each group. In 5 patients of the lactulose group and in 6 of the lactitol group there was a moderate improvement of PSE during the study. Finally, 4 patients in the lactulose group and 3 in the lactitol group did not respond to treatment. No side effects attributable to therapy were observed in either group. These results indicate that lactitol is as effective as lactulose in the management of patients with cirrhosis and acute PSE.  相似文献   
995.
Successful treatment of an infected vascular graft with gentamicin beads   总被引:1,自引:0,他引:1  
This short report describes the successful healing of an infected axillo-bifemoral graft by the insertion of Gentamicin beads, this technique cannot be recommended for all infected grafts the majority of which will have to be removed and replaced.  相似文献   
996.
The ameloblastoma is a tumor arising predominantly in the mandible from odontogenic epithelium, and is locally invasive. It is rarely malignant; but even when benign, it causes gross local destruction and expansion of tissue. Growth is persistent, and recurrence may occur more than a decade after presumed total resection. Surgical resection should include a reasonable margin of healthy tissue whenever possible. Late patient presentation due to a paucity of symptoms, and insiduous tumor growth patterns render complete removal of the ameloblastoma difficult. Follow-up examinations should span a prolonged period, exceeding 10-15 years.  相似文献   
997.
Fifty-four patients with 65 superficial malignant lesions were treated by local hyperthermia combined with radiation therapy at the National Cancer Center Hospital, Tokyo. Hyperthermia was delivered with an Aloka Model HMS-020 (2450 MHz) or with a horn-type applicator of BSD-1000 (80-90 MHz). Relatively small tumours, those less than 4 cm in thickness, were treated by using 2450 MHz while 80-90 MHz delivered through the horn-type applicator was used for tumours exceeding 5 cm in thickness. The radiation dose was 4 Gy twice a week or 2 Gy five times a week, the total dose being 40-60 Gy. A total of six to 10 hyperthermia treatments ranging from 40 to 60 min each, with the tumour heated to more than 42.5 degrees C, were given twice a week within 1 h following radiation therapy. Complete response was achieved in 16 of the 30 patients (55 per cent) treated with the 2450 MHz microwave, and partial response in seven others (23 per cent). Tumours treated with the BSD-1000 achieved complete response in 10 out of 33 patients (30 per cent) and partial response in nine others (27 per cent). In five out of nine patients classified as partial responders, however, complete disappearance of tumour cells was noted by post-treatment histological examination. Complete plus partial response rates were thus essentially the same with the Aloka HMS-020 and the BSD-1000, though the rate of complete response was apparently higher with the Aloka unit, probably because it was used on smaller tumours.  相似文献   
998.
The effects of bedtime 70 micrograms and twice daily 35 micrograms doses of enprostil on 24-hour intragastric acidity were investigated in nine duodenal ulcer patients in remission. Median nocturnal acidity decreased significantly by 30% with 35 micrograms twice daily, and by 48% with 70 micrograms at bedtime. In a clinical trial using bedtime dosing, 102 duodenal ulcer patients randomly received either ranitidine 300 mg or enprostil 70 micrograms. More ulcers healed after 4 and 8 weeks treatment with ranitidine than with enprostil (76% ranitidine vs 52% enprostil, at 4 weeks p = 0.0065 and 94% vs 68%, respectively at 8 weeks, P = 0.0007). However, 6 months after cessation of treatment there was no material difference in overall outcome. Despite combining mucosal protection with acid inhibition enprostil treatment conferred no advantage over simple acid inhibition.  相似文献   
999.
1000.
In order to examine time trends of the prevalences of HBeAg positives among HBV carriers in Japan, we analysed data on HBeAg of HBsAg positive voluntary blood donors (23,560 males, and 8659 females) at the Osaka Red Cross Blood Centre between January 1977 and March 1984. Age-specific prevalences of HBeAg positives decreased year by year for both sexes, especially for those in their teens and twenties. The prevalences of HBeAg positives decreased with age, but at any given age it was lower for the later than for the earlier birth cohorts. Although reasons for the secular declines are unknown, the findings suggest that the prevalence of HBeAg positives among HBV carriers will continue to decrease in Japan. This, together with the immunization programme implemented this year, may lead to a future reduction in the risk of HBV related liver diseases in Japan.  相似文献   
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