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41.
[Purpose] This study aimed to determine the effect of delayed visual feedback on the center of pressure and sitting balance in patients with stroke. [Participants and Methods] This was a single-blinded, randomized crossover trial. The duration of each intervention in real-time visual feedback and delayed visual feedback conditions while sitting on the platform was five days. We measured the center of pressure, function in sitting test, and functional independence measure for physiotherapy assessment. [Results] Twenty patients with stroke were included in this study. The delayed visual feedback condition improved the center of pressure for lateral distance, function in sitting test, and functional independence measure. The lateral center of pressure deviation increased significantly after 500 ms of intervention. The function in sitting test evaluated the interaction between pre- and post-training, and these conditions revealed that timing and condition factors contributed to the improvement. Sitting balance training affected the functional independence measure. [Conclusion] Sensory-motor and cognitive learning was facilitated through balance training with delayed visual feedback, and the internal model was updated with the efference copy of error correction. Sensory-motor feedback to visual stimulation can improve postural control, balance, and activities of daily living.  相似文献   
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A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes.  相似文献   
43.
This retrospective study clarified the success rate of endoscopic endodontic surgeries and identified predictors accounting for successful surgeries. In this retrospective study, 242 patients (90 males, 152 females) who underwent endoscopic endodontic surgery at a single general hospital and were diagnosed through follow-up one year later were included. Risk factors were categorized into attributes, general health, anatomy, and surgery. Then, the correlation coefficient was calculated for the success or failure of endodontic surgery for each variable, the odds ratio was calculated for the upper variable, and factors related to the surgical prognosis factor were identified. The success rate of endodontic surgery was 95.3%, showing that it was a highly predictable treatment. The top three correlation coefficients were post, age, and perilesional sclerotic signs. Among them, the presence of posts was the highest, compared with the odds ratio, which was 9.592. This retrospective study revealed the success rate and risk factors accounting for endoscopic endodontic surgeries. Among the selected clinical variables, the presence of posts was the most decisive risk factor determining the success of endodontic surgeries.  相似文献   
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Purpose The aim of this retrospective analysis was to evaluate the accuracy of 10 mm thickness single helical computed tomography (CT) examination for confirming the diagnosis of appendicitis or providing a diagnosis other than appendicitis, including underlying periappendical neoplasms. Materials and methods From April 1, 2001 to March 30, 2005, a total of 272 patients with suspected appendicitis underwent CT examinations. Of the 272 patients, 106 (39%) underwent surgery. Seven CT examinations for seven patients were excluded because of inconsistency of the CT protocol. We therefore reviewed 99 CT images (99 patients) with correlation to surgical-pathological findings to clarify the diagnostic accuracy of CT examinations. We compared the postoperative diagnosis with the preoperative CT report. The final diagnoses were confirmed by macroscopic findings at surgery and pathological evaluations if necessary. Results Of the 99 patients, 87 had acute appendicitis at surgery. The sensitivity, specificity, and accuracy of CT were 98.9%, 75.0%, and 96.0%, respectively. The positive predictive value and negative predictive value were 96.6% and 90.0%, respectively. Among nine patients in the true-negative category, five had colon cancers; and among three patients in the false-positive category, two had cancer of the cecal-appendiceal region as the underlying disease. Conclusion CT examination is useful for patients with suspected appendicitis, but radiologists should be aware of the limitation of thick-sliced single helical CT. They should also be aware of the possibility of other diseases, including coincident abdominal neoplasms and underlying cecal-appendiceal cancer.  相似文献   
48.
OBJECTIVE: To investigate whether preoperative corticosteroid administration plays a role in attenuating postoperative morbidity. SUMMARY BACKGROUND DATA: There is as yet no consensus on the beneficial effects of steroids in alleviating surgical stress. METHODS: A total of 66 patients undergoing surgery for thoracic esophageal cancer were randomly categorized preoperatively into two groups of 33 patients each. One group was administered an intravenous infusion of methylprednisolone (10 mg/kg body weight) 30 minutes before the surgery (MP group), while the other group received a placebo infusion (control group). The primary endpoint was organ system failure during the first 7 days after surgery. Comparisons of surgery-related complications, cytokine responses, and blood counts were also made between the two groups. RESULTS: The percentage of patients in the MP group who had one or more organ system failures was 33%, significantly lower than the corresponding percentage of 61% in the control group. The surgery-related complication rate and long-term survival rate were similar in the two groups. The peak plasma levels of interleukin (IL)-1 receptor antagonist, IL-6, and IL-8 were significantly lower in the MP group than in the control group. Changes in the plasma levels of IL-10 were significantly larger in the MP group. No significant differences in the circulating lymphocyte and neutrophil counts were observed between the groups. CONCLUSIONS: The results suggest that prophylactic administration of corticosteroids is associated with a decrease in postoperative morbidity in patients undergoing invasive surgery. The laboratory data suggest that corticosteroids may attenuate surgical stress-induced inflammatory responses both directly by suppressing the release of proinflammatory cytokines and via inducing IL-10 synthesis.  相似文献   
49.
We established a three-dimensional finite element method (FEM) model of the 4th and 5th vertebrae, using computed tomography (CT) images (2-mm slice thickness) of a healthy 29-year-old man. Because of the lack of specific data regarding the material characteristics of the nucleus pulposus of intervertebral discs, we used intradiscal pressure in the nucleus pulposus to establish the model. We referred to data from Nachemson and from Sato et al. regarding intradiscal pressure and to the methods of Shirazi-Adl for data for other material characteristics (see text for these references). The mid-position model bears a load of 294 N in the vertical direction, while the models of the flexed and extended positions bear loads of 15 N-m. In addition, a degenerative disc model without intradiscal pressure was created for the standing model. The use of these models allowed the investigation of von Mises stress on the vertebral endplates and the annulus fibrosus. We also examined von Mises stress on the facet joint in normal and degenerative disc models. There was increased von Mises stress on the vertebral endplate in the anterior, center portions. von Mises stress on the annulus fibrosus increased in the posterior portion, the entrance to the neural foramen, and the exit of the neural foramen. von Mises stress was greater during flexion in the posterior portion; in particular, increasing to about 1.6 times the level seen with other postures. No changes were observed in von Mises stress on the vertebral endplates or annulus fibrosus in the degenerative disc model, but von Mises stress on the facet joints was about 2.5 times that seen in the normal disc model. Received: June 28, 2001 / Accepted: October 27, 2001  相似文献   
50.
Purpose. To investigate the differences in recovery of postural stability, after obtaining similar intravenous sedation levels with midazolam, in elderly and younger patients undergoing dental surgery. Methods. We studied 15 elderly patients (>65 years) and 15 younger patients (<55 years) after intravenous sedation. Midazolam was carefully titrated over 4–5 min until slow response to verbal commands, ptosis of the eyelid, or slight slurring of speech was obtained. Parameters were postural balance tests and an addition test, as a psychomotor function test. Results. The dose of midazolam in the elderly group (0.045 ± 0.012 mg·kg−1) was 62% of that in the younger group (0.074 ± 0.026 mg·kg−1). In evaluation of the percentile rank of a balance test with a visual feedback system, which contained a dynamic balance element, recovery at 60 min in the elderly group was significantly slower than that in the younger group. However, the recovery times for the balance test and the addition test, at which the significantly changed values were restored to the baseline values, were 120 min and 90 min, respectively, in both groups. Conclusion. In the recovery from sedation, elderly patients had more difficulty in acquiring postural adjustment during movement than in maintaining a standing posture. If the dose is carefully administered, however, even elderly patients might be able to return home 2 h after midazolam administration, as could the younger patients. Received: November 6, 2001 / Accepted: April 22, 2002  相似文献   
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