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71.
BACKGROUND: Laparoscopic gastric banding is a minimally invasive bariatric operation that is increasing in popularity at many centers worldwide. Although this procedure is not yet approved in the United States, clinical trials are ongoing. METHODS: We report our results of a 3-year follow-up on 60 patients who underwent the laparoscopic gastric band procedure for the treatment of morbid obesity. The procedure was performed at the Wesley Obesity Clinic in Brisbane, Australia. RESULTS: At follow-up, 51 of the 60 patients (85%) still had the laparoscopic gastric band in place. All of the patients had a lower body weight after undergoing the procedure. The average weight loss was 39 kg (range 2 to 98 kg), representing a loss of 65% of average excess body weight. Twenty-five of 51 patients (49%) regained some weight after their initial loss, but the average amount was only 5 kg. The remaining 26 patients have remained at their lowest body weight recorded after the procedure or are continuing to lose weight. There was no operative mortality. Complications predominantly were caused by band slippage (21%), which has been nearly eliminated in recent practice (1 slip in the last 225 cases). Subsequent modifications in the technique to prevent band slippage included placing the band near the level of the esophagus, with minimal disruption of the posterior gastric attachments and diligent suturing of the band in place. CONCLUSIONS: We conclude that the laparoscopic gastric band is effective in short- and long-term weight loss. The high rate of reoperation for repositioning has been avoided in current practice. 相似文献
72.
Low-dose mifepristone followed by vaginal misoprostol at 48 hours for abortion up to 63 days 总被引:10,自引:0,他引:10
The aim of this study was to compare the effectiveness, side effects, and acceptability of one-third the standard dose of mifepristone, i.e., 200 mg, and vaginal misoprostol 800 microg to induce abortion in subjects < or =56 days pregnant with subjects 57-63 days pregnant. A prospective multicenter trial enrolled healthy women > or =18 years, < or =63 days pregnant, and wanting an abortion. Women received mifepristone 200 mg orally, followed by misoprostol 800 microg vaginally, and returned 1-4 days later for ultrasound evaluation. A second dose of misoprostol was administered, if necessary. Surgical intervention was indicated for continuing pregnancy, excessive bleeding, or persistent products of conception 5 weeks later. Of 1137 subjects, 829 were in the < or =56 days pregnant group and 308 in the 57-63 days pregnant group. In all, 34 subjects had surgical intervention and 16 were lost to follow-up. Complete medical abortions occurred in 97% of subjects < or =56 days pregnant and 96% in the 57-63 days pregnant group. In all, 88% of subjects in the < or =56 days pregnant and 92% in the 57-63 days pregnant group bled within 4 h of using vaginal misoprostol. Comparing subjects < or =56 days pregnant with 57-63 days pregnant, there was less diarrhea (20% vs 29%, p = 0.002) and vomiting (33% vs 44%, p = 0.001), although side effects were acceptable to 82% of subjects in both groups. One subject in the < or =56 day group required a transfusion for delayed excessive bleeding. Although bleeding (p = 0.01) and pain (p = 0.02) were less acceptable in the 57-63 day group, 91% of subjects in both groups reported that the overall procedure was acceptable. In summary, low-dose mifepristone 200 mg and home administration of vaginal misoprostol 800 microg at 48 h were highly effective and acceptable to women < or =63 days pregnant, thereby expanding the number of women who can access a medical abortion. 相似文献
73.
Fayers PM Cuschieri A Fielding J Craven J Uscinska B Freedman LS 《British journal of cancer》2000,82(1):213-219
The UK Medical Research Council (MRC) randomized trial of gastric surgery, ST01, compared conventional (D1) with radical (D2) surgery. Sample size estimation was based upon the consensus opinion of the surgical members of the design team, which suggested that a change in 5-year survival from 20% (D1) to 34% (D2) could be realistic and medically important. On the basis of these survival rates, the sample size for the trial was 400 patients. However, this trial was exceptional in the way that a survey of surgeons' opinions was made at the start of the trial, in 1986, and again before results were analysed but after termination of the trial in 1994. At the initial survey, the three surgeons from the trial steering committee and 23 other surgeons experienced in treating gastric carcinoma were given detailed questionnaires. They were asked about the expected survival rate in the D1 group, anticipated difference in survival from D2 surgery, and what difference would be medically important and influence future treatment of patients. The consensus opinion of those surveyed was that there might be a survival improvement of 9.4%. In 1994, prior to closure of the trial, and before any survival information was disclosed, the survey was repeated with 21 of the original 26 surgeons. At this second survey, the opinion of the trial steering committee was that 9.5% difference was more realistic. This was in accord with the opinion of the larger group, which remained little changed since 1986. The baseline 5-year D1 survival was thought likely to be about 32%, which corresponded closely to the actual survival of recruited patients. Revised sample size calculations suggested that, on the basis of these more recent opinions, between 800 and 1200 patients would have been required. Both surveys assessed the level of treatment benefit that was deemed to be sufficient for causing surgeons to change their practice. This showed that the 13% difference in survival used as the study target was clinically relevant, but also indicated that many clinicians would remain unwilling to change their practice if the difference is only 9.5%. The experience of this carefully designed trial illustrates the problems of designing long-term, randomized trials. It raises interesting questions about the common practice of basing sample size estimates upon the beliefs of a trial design committee that may include a number of enthusiasts for the trial treatment. If their opinion of anticipated effect sizes drives the design of the trial, rather than the opinion of a larger community of experts that includes sceptics as well as enthusiasts, there is likely to be a serious miscalculation of sample size requirements. 相似文献
74.
Smoking: health effects and control (1) 总被引:9,自引:0,他引:9
J E Fielding 《The New England journal of medicine》1985,313(8):491-498
75.
76.
77.
In vitro translation of hypoxanthine/guanine phosphoribosyltransferase mRNA: characterization of a mouse neuroblastoma cell line that has elevated levels of hypoxanthine/guanine phosphoribosyltransferase protein. 总被引:16,自引:6,他引:10 下载免费PDF全文
D W Melton D S Konecki D H Ledbetter J F Hejtmancik C T Caskey 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(11):6977-6980
Antibody specific for the native form of Chinese hamster hypoxanthine/guanine phosphoribosyltransferase (HPRT; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) was used to detect the synthesis of HPRT protein in a rabbit reticulocyte lysate translation system primed with mRNA from Chinese hamster tissues and cultured cells. Electrophoretic analysis of the immunopurified products from the translation of mRNA from wild-type and a series of mutant Chinese hamster cells indicated that HPRT synthesis in vitro qualitatively and quantitatively corresponded to synthesis in vivo. The translation system was used to identify two mRNA sources producing high levels of HPRT protein: Chinese hamster brain and a mouse neuroblastoma HPRT revertant cell line, NBR4. Translation of NBR4 mRNA generated 25-50 times more HPRT protein than mRNA from wild-type cells. The basis for HPRT overproduction is considered in view of an X chromosome alteration found in NBR4 cells. 相似文献
78.
79.
The efficacy of ranitidine (150 mg twice daily) and cimetidine (200 mg three times daily and 400 mg at night) in the short-term healing of duodenal ulcer has been assessed in a randomized controlled trial involving 106 patients. There were 3 drop-outs. Forty-two out of 53 patients (79%) treated with ranitidine had healed ulcers at 4 weeks compared with 37 out of 50 treated with cimetidine (74%). This difference is not significant. At 8 weeks the healing rate for ranitidine (98%) was significantly greater than that for cimetidine (86%) (P less than 0.05). There was no significant difference in healing rates between men and women and between smokers and non-smokers. Side effects were not a problem with either drug. There were no differences of clinical significance between laboratory values in the two treatment groups, although a minor increase in mean creatinine levels occurred in the cimetidine-treated group. 相似文献
80.
Facial bone fractures in children 总被引:2,自引:0,他引:2
M A Fortunato A F Fielding L H Guernsey 《Oral surgery, oral medicine, and oral pathology》1982,53(3):225-230
From the aforementioned study, the following conclusions can be stated: (1) Patients ranged from 2 to 15 years of age, with no one age group being more susceptible to facial fractures. This fact is contrary to previous findings. (2) No true orbital blow-out fractures were found in patients less thn 7 years of age, primarily because of the lack of maxillary sinus development in that age group. The most rapid development of the maxillary sinus occurs between the ages of 7 to 15 years. (3) In patients from 2 to 7 years of age, fractures occurred at an even ratio of boys and girls. From 8 to 15 years of age there was a boy: girl ratio of about 4.5:1. Of the sixty-seven total patients in the study, boys outnumbered girls by a ratio fo 2.4:1. In order, the condyle, orbit, and mandible were the most common fracture sites observed in the study. This fact is in agreement with past studies. There was no predominant site for any age group or sex. While falls were singly responsible for the greatest number of facial fractures, automobile-related trauma accounted for 47.7 percent of facial fractures in children. In the majority of cases multiple mandibular fractures were of the bilateral condylar type. Hospitalization of patients with automobile-related fractures was approximately 3 days longer than that of patients whose fractures occurred from other causes. More than two thirds of the patients in the study had associated trauma-related medical and dental injuries. 相似文献