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141.
Hybridomas were developed which secreted antibodies to the core and outer capsids of rice dwarf virus (RDV). The reactive proteins of RDV were simply and rapidly analyzed using monoclonal antibody (MoAb)-coupled Affi-Gel 701 beads and SDS polyacrylamide gel electrophoresis and were isolated with a MoAb-coupled Sepharose 4B affinity column.  相似文献   
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BACKGROUND: This clinical study evaluated changes in motor evoked potentials (MEP) elicited by direct cerebral cortical stimulation and evoked spinal cord potentials (ESCPs) elicited by direct spinal cord stimulation during selective intercostal arterial perfusion for thoracoabdominal aortic aneurysm (TAAA) repair. We also determined the efficacy of this perfusion method for prevention of paraplegia. METHODS: Two kinds of ESCPs and MEPs were monitored during the prosthetic replacement step for TAAA surgeries. We performed selective intercostal arterial perfusion from the T7 intercostal artery to the L1 intercostal artery through a small piece of Dacron graft while monitoring spinal cord potentials in five cases of TAAA. RESULTS: The MEP amplitude decreased after clamping the aorta but quickly recovered after selective perfusion of intercostal arteries. Other spinal cord potentials did not change during the reconstruction of intercostal arteries. Postoperative paraplegia or parapalesis did not occur in any of the patients. CONCLUSIONS: Monitoring of MEPs during selective intercostal arterial perfusion was a useful adjunct to prevent postoperative paraplegia in TAAA surgery.  相似文献   
145.
T Saito  T Yamamuro  J Shikata  M Oka  S Tsutsumi 《Spine》1991,16(5):494-502
Postlaminectomy deformities were simulated in the cervical or cervicothoracic spine by the use of a displacement incremental method based on finite-element analysis combined with composite material and spanning element theory. The simulation analyses revealed that the primary cause of postlaminectomy deformity was the resection of one or more spinous processes and/or posterior ligaments (ie, ligamenta flava, supraspinous, and interspinous ligaments). After their removal, the tensile stresses that were preoperatively distributed through the posterior ligaments were transferred to the facets. This led to an imbalance of the stresses on the spinal bodies, causing deformity. The gravitational center of the head determined whether the deformity would develop as a kyphosis or increasing lordosis. As the elastic modulus of the soft tissue composites (eg, end plates, ligaments, and facets) increased, a kyphotic deformity changed gradually from swan-neck deformity, to extreme kyphotic deformity with a large curvature, and finally to a straightening deformity. Progressive kyphotic deformity is found only in children.  相似文献   
146.
Purpose We performed a meta-analysis of randomized controlled trials to determine the optimal timing of laparoscopic cholecystectomy and open cholecystectomy for acute cholecystitis.Methods We retrieved randomized controlled trials (RCTs) that compared early with delayed cholecystectomy for acute cholecystitis by systematically searching Medline and the Cochrane Library for studies published between 1966 and 2003. The outcomes of primary interest were mortality and morbidity.Results The ten trials we analyzed comprised 1 014 subjects; 534 were assigned to the early group and 480 assigned to the delayed group. The combined risk difference of mortality appeared to favor open cholecystectomy in the early period (risk difference, −0.02; 95% confidence interval, −0.44 to −0.00), but no differences were found among laparoscopic procedures or among all procedures. The combined risk difference of morbidity showed no differences between the open and laparoscopic procedures. The combined risk difference of the rate of conversion to open surgery showed no differences in the included laparoscopic studies; however, the combined total hospital stay was significantly shorter in the early group than in the delayed group.Conclusions There is no advantage to delaying cholecystectomy for acute cholecystitis on the basis of outcomes in mortality, morbidity, rate of conversion to open surgery, and mean hospital stay. Thus, early cholecystectomy should be performed for patients with acute cholecystitis.  相似文献   
147.
From 1974-8, 808 postoperative choledochoscopy procedures, conducted by insertion of choledochofiberscope into the biliary tract through the sinus tract after the T-tube had been removed, were carried out in 292 patients at Teikyo University Hospital, Tokyo, Japan. In this series, 104 with retained biliary tract stones were encountered, and complete removal of stones was successfully carried out in 101, using postoperative choledochoscopy. Any failures of removal of retained biliary tract stones were attributed to improper insertion of the T-tube. The T-tube, of at least 18 French calibers should be inserted into the common bile duct at a right angle so as to obviate a tortuous sinus tract. The follow-up study in cases of complete extraction of the retained biliary tract stones showed that this approach is most effective. Recurrent stone with a silk nidus was found in one patient in whom postoperative choledochoscopy had been performed one year previously. Reoperation was carried out in this particular case. All other patients have remained asymptomatic. Finally, we advise routine use of postoperative choledochoscopy as an adjunct to the T-tube cholangiography, in order to prevent the possibility of retained biliary tract stones. Contents of this paper were read before the Annual Meeting of the American Society for Gastrointestinal Endoscopy, Digestive Disease Week '79 on May 22nd, 1979 in New Orleans, U.S.A.  相似文献   
148.
Objective: Gastric cancer (GC) and adenoma (GA) are reported to be related to atrophic gastritis, in which the serum pepsinogen (PG) I level and the PGI/PGII ratio (I/II ratio) are reduced. To verify that the finding of a low PG level increases the risk for GC and GA, we investigated the correlation between low PG levels and the prevalence of GC and GA in individuals.
Methods: The 2,039 subjects (734 Japanese men, mean age 68.5 yr, and 1,305 women, mean age 66.7 yr), selected from among 10,996 local residents who underwent health check-ups based on reductions in their serum PG levels, underwent upper gastrointestinal endoscopy.
Results: Gastrointestinal endoscopy detected 21 GCs and 15 GAs. The prevalence of GC was higher than that in the residents without low serum PG. The percentage of early stage of GC (90%) was significantly higher than that of GC detected in unscreened residents (56.9%). The prevalence of GC in men was closely and significantly correlated with the I/II ratio (  r = 0.935  ,   p = 0.0063  ), whereas there was less correlation with age (  r = 0.842  ,   p = 0.0734  ). The prevalence of GA was also closely and significantly correlated with the I/II ratio in men (  r = 0.881  ,   p = 0.0203  ), but not with age (  r = 0.163  ,   p = 0.7928  ). In women the prevalence of GC (r 5 0.744,   p = 0.090  ) and GA (  r = 0.678  ,   p = 0.1392  ) did not correlate as strongly with the I/II ratio, although the highest prevalence was seen in the group with the lowest I/II ratio.
Conclusion: Our study verified that a low I/II ratio signifies a high risk for GC and GA and that measuring serum PG levels can be used as a screening method for GC and GA.  相似文献   
149.
The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of gemtuzumab ozogamicin (GO) in patients with relapsed and/or refractory CD33-positive acute myeloid leukemia (AML). Patients received 2-h infusions of GO twice with an interval of approximately 14 days. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria Version 2.0. Samples for pharmacokinetics were taken on day 1 and day 8 of the first treatment cycle. The dose was increased stepwise and, in each cohort, patients were treated at the same dose. Forty patients, median age 58 years (range 28–68) were treated; 20 and 20 patients were enrolled to the phase I and II parts, respectively. In the phase I part, dose-limiting toxicities (DLTs) were hepatotoxicities, and the recommended dose was established as 9 mg/m2 given as two intravenous infusions separated by approximately 14 days. The pharmacokinetic study revealed that C max and AUC were equivalent to those of non-Japanese patients. In the phase II part, complete remission was observed in 5 patients, and one patient had complete remission without platelet recovery. Four of these 6 in remission and one in the phase I are long-term survivors (alive for at least 44 months). GO is safe and effective as a single agent among Japanese CD33-positive AML patients. Remission lasted longer in a subset of patients than in non-Japanese patients in earlier studies. Further studies of this agent are warranted to establish standard therapy. S. Furusawa: deceased.  相似文献   
150.
Overproduction of nitric oxide by inducible nitric oxide synthase (iNOS) acts cytotoxically and contributes to inflammation. We explored the roles of iNOS in the pathogenesis of Helicobacter pylori-associated diseases. Using reverse-transcribed PCR, we examined topographical patterns of iNOS mRNA expression in the gastroduodenal mucosa in H. pylori-negative controls and H. pylori-positive patients with duodenal ulcer (DU), gastric ulcer (GU), and ulcer-free gastritis. iNOS expression showed topographical variations among the tested disorders. As compared to controls, DU had a significantly higher expression of iNOS mRNA in the duodenum, GU in the antrum and duodenum, and gastritis in the antrum and corpus. H. pylori eradication yielded a significant reduction of iNOS mRNA in the duodenum of DU and in the antrum of GU. Diverse topographical patterns of H. pylori-induced iNOS expression may contribute to mechanisms by which H. pylori elicits different clinical disorders.  相似文献   
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