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991.
992.
993.
Aims:

The treatment of long-standing dislocation of the temporomandibular joint is broadly classified into open reduction and closed reduction. The current study presents a case of long-standing dislocation of the temporomandibular joint treated 3 years after dislocation. In this study, the authors evaluated the long-term outcome of conservative reduction by lever action of chronic bilateral mandibular condyle dislocation.

Methodology:

Manual repositioning of temporomandibular joint dislocation lasting for 3 years in a 31-year-old woman was attempted without success; therefore, conservative reduction by lever action was carried out because the patient declined treatment under general anesthesia.

Results:

The treatment was discontinued after 6 days because of the subluxation of the retaining tooth. The retainer was changed from tooth to screw for intermaxillary fixation, and treatment was reinstituted. Fifteen days later, reduction was achieved and retention was started and continued for 2 months. The outcome was good, with no recurrent dislocation within 24 months of the treatment.

Conclusions:

Conservative reduction by lever action, involving minimally invasive treatment and little dysfunction, should be considered an optional conservative treatment.  相似文献   

994.
Zirconia‐based dental restorations are becoming used more commonly. However, limited attention has been given to the difficulties experienced, concerning cutting, in removing the restorations when needed. The aim of the present study was to compare the cutting efficiency of diamond burs, operated using an electric high‐speed dental handpiece, on zirconia (Zir) with those on lithium disilicate glass–ceramic (LD) and leucite glass–ceramic (L). In addition, evaluation of the cutting efficiency of diamond burs on Zir of different thicknesses was performed. Specimens of Zir were prepared with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm, and specimens of LD and L were prepared with a thickness of 1.0 mm. Cutting tests were performed using diamond burs with super coarse (SC) and coarse (C) grains. The handpiece was operated at 150,000 rpm with a cutting force of 0.9 N. The results demonstrated that cutting of Zir took about 1.5‐ and 7‐fold longer than cutting of LD and L, respectively. The SC grains showed significantly higher cutting efficiency on Zir than the C grains. However, when the thickness of Zir increased, the cutting depth was significantly decreased. As it is suggested that cutting of zirconia is time consuming, this should be taken into consideration in advance when working with zirconia restorations.  相似文献   
995.
We studied the changes in urinary bicarbonate, urinary pH and some physical parameters such as minute ventilation (VE), oxygen consumption (VO2), respiratory carbon dioxide (VCO2), heart rate, blood pressure, and blood lactate, before and after the submaximal exercise. Six male subjects aged 28-33 years were involved in the study. They performed the incremental exercise test using a bicycle ergometer until exhaustion. Levels of VE, VO2, VCO2, heart rate, and blood pressure increased continuously with an increase in cycling intensity. These parameters markedly decreased and reached the baseline levels within 5-10 minutes after the termination of exercise. According to an increase in cycling intensity, blood lactate increased continuously during exercise, but after termination of exercise the return of lactate to the baseline level was markedly retarded. Urinary bicarbonate and pH were within the range of those at 0 time (baseline levels) from the beginning until 30 minutes after the exercise. However, they began to increase abruptly about 30 minutes after the exercise, and continued to increase extensively for 2 hours thereafter. Such marked increase in urinary bicarbonate and pH seemed to be correlated with the aerobic metabolism of lactate in the muscles, liver, and kidney, finally producing CO2. It was also suggested that the measurement of urinary bicarbonate and pH may be useful for the estimation of physiological changes in the body after submaximal incremental cycling exercise loading.  相似文献   
996.
Melanoma is the most lethal skin cancer. Most deaths from melanoma result from metastases. Semaphorins have been shown to inhibit neuronal and endothelial cell migration, but the effects of semaphorins on tumor metastasis have not been documented. We found that semaphorin 3F (SEMA3F) was markedly downregulated in highly metastatic human cell lines in vitro and in vivo, which suggested that it may be a metastasis inhibitor. Metastatic human melanoma cells were transfected with SEMA3F and implanted into mice; the resultant tumors did not metastasize. Rather, the primary tumors resembled benign nevi characterized by large areas of apoptosis, diminished vascularity, inhibition of hyperplasia in overlying epidermal cells, and encapsulated tumor borders delineated by thick layers of fibroblasts and collagen matrix. This phenotype is in stark contrast to highly invasive, vascular mock-transfected tumors. In vitro, tumor cells expressing SEMA3F had a diminished capacity to adhere and migrate on fibronectin. Consistent with semaphorin-mediated chemorepulsion of neurons, tumor cells expressing SEMA3F were chemorepulsive for vascular and lymphatic endothelial cells expressing neuropilin-2 (NRP2), a novel mechanism for a tumor angiogenesis inhibitor. The repulsive activity was abrogated by NRP2 RNA interference. Together these results indicate that SEMA3F is a potent metastasis inhibitor that targets both tumor and stromal cells and raise the possibility of SEMA3F having therapeutic potential.  相似文献   
997.
We present a very rare case of rectal cancer in a patient with situs inversus totalis (SIT), which is a complete transposition of the thoracic and abdominal viscera. A woman in her 60s visited a local hospital reporting bloody stool and was diagnosed with upper rectal cancer and SIT. We made careful preoperative preparations for the congenital anomaly, and robotic-assisted high anterior resection with D3 lymph node dissection was performed. Although we adopted an unusual six-port placement, the operation was performed safely and efficiently without any adverse events. The patient recovered uneventfully. The pathological specimen was classified as pT3N2bM0 with negative resection margins. Robotic-assisted surgery is advantageous for rectal cancer treatment even when anatomical abnormalities make the surgical procedure more difficult.  相似文献   
998.
目的观察葡萄糖耐量(OGTT)前1天高脂低碳水化合物撮入(热量相同但碳水化合物撮入减少,脂肪撮入增加)对健康成人糖耐量的影响,从而进一步确定是否OGTT前1天高脂低碳水化合物(HF)撮入导致糖耐量减低(IGT)的误诊。方法30例男性健康成人随机分为两组(HF组和对照组)进行交叉试验;分别于OGTT前1天早、中、晚餐时撮入热量相同的HF或对照配餐;次日清晨行75g OGTT;分别测定血糖、胰岛素、游离脂肪酸、甘油三酯厦胆固醇浓度;2次OGTT间隔1周。结果OGTT前1天HF使糖负荷后30、60、120分钟血糖分别升高33%、51%厦42%,胰岛素分泌指数(△I/△G)降低50%,空腹血浆游离脂肪酸(FFA)浓度上升100%,使30%健康成人被误诊为IGT。结论即使总热量撮入相同,OGTT前1天HF引起健康成人空腹血浆游离脂肪酸水平升高,抑制早期胰岛素分泌,引起糖负荷后血糖的升高,导致IGT的误诊。  相似文献   
999.
AIM: The many studies into the relation between cigarette smoking and the risk of ovarian cancer have produced inconsistent results. Here we investigated this relation using data from the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, initiated in 1988. METHODS: A self-administered questionnaire on smoking habits and other risk factors for cancer was completed by 34 639 Japanese women. After 7.6 years of follow up, 39 cases of ovarian cancer were available for analyses. Cox proportional-hazards models were used to compute relative risks (RR) and to adjust for confounders. RESULTS: Relative to those who had never smoked, the RR of ovarian cancer were 1.63 (95% confidence interval [CI] = 0.21-12.50) for former smokers and 2.27 (95% CI = 0.85-6.08) for current smokers. Among current smokers, the RR were 1.48 (95% CI = 0.20-10.92), 5.56 (95% CI = 1.68-19.06), and 1.86 (95% CI = 0.25-14.30) among women who smoked <10, 10-19, and at least 20 pack-years ([number of cigarettes smoked per day/20] x number of years subject has smoked), respectively, relative to those who had never smoked. A test for trend was statistically significant (P = 0.044). CONCLUSIONS: These data indicate that cigarette smoking increases the risk of developing ovarian cancer in the Japanese population.  相似文献   
1000.
This report presents a case of pulmonary tuberculosis with atypical histopathological manifestations in an immunocompetent patient. A 37-year-old Japanese man was admitted due to multiple small nodules on chest computed tomography (CT). He was diagnosed with pulmonary tuberculosis following a culture of acid-fast bacterium from suction sputum specimens obtained by bronchoscopy. The histopathological findings from video-assisted thoracoscopy revealed small, sporadically organized, and fibrotic lesions with infiltration of eosinophils, plasma cells, and lymphocytes. The administration of antitubercular drugs eliminated the abnormal shadows on chest CT. Extreme care must be taken in the diagnosis of a patient with inexplicable histopathological findings.  相似文献   
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