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71.
OBJECTIVE: To evaluate the possibility and reliability of the hyoid-sternohyoid graft transfer in the correction of server subglottic laryngotracheal stenosis, and delineate the operation skills and clinical results. METHODS: Seven patients with severe subglottic stenosis underwent laryngotracheal reconstruction using the hyoid grafts with sternohyoid muscle flaps (HG-SHMF). Five of these patients had traumatic subglottic stenosis, one with scar tissue of unknown etiology arising in the subglottic region, another with tracheal narrowing caused by inhalation of hydrochloric acid. RESULTS: All seven patients were successfully decannulated with moderate good voice. The average time from reconstruction to decannulation was 15.4 months. The stent was endoscopically removed with a range of 3 to 22 months; the mean time required for stenting was 9.6 months. Two patients who received additional salvage reconstruction procedures because of graft or stent displacement were extubated with improved voices and satisfactory airway. CONCLUSIONS: The HG-SHMF transfer was a single-stage reconstruction, relatively simple procedure that can restore an adequate airway and a good voice. Patients undergoing laryngotracheal reconstruction with HG-SHMF must have regular, long-term follow-up since graft displacement and recurrent granulation tissue or scar reformation can cause restenosis after an initially successful surgery. This procedure should be used in a large number of patients to further test its reliability.  相似文献   
72.
A commercially available ADAC Pinnacle(3) radiation treatment planning system has been used to model electron beams from a Varian Clinac 2300C/D in the energy range of 6 to 22 MeV. Prior to clinical use, the dosimetric characteristics of the beams have to be modeled accurately. As a first step for beam modeling, a number of dose profile and depth dose measurements were taken at standard source-to-surface distance (SSD) of 100 cm. Dose profiles and depth dose measurements at extended SSDs up to 120 cm are important for ascertaining accuracy of the model, as well as their clinical usefulness in the treatment of some sites (e.g., head-and-neck tumors). Modeled and measured beam data were compared. Over 98% of comparison points (modeled vs. measured) at 100-cm SSD were within 2.5% or 2.5 mm. At 110 cm SSD, over 98% of compared points were within 4% or 4 mm, and at 120-cm SSD, over 98% of compared points were within 5% or 5 mm. Overall, more than 98% of compared points were within 4% or 4 mm. Better models were produced for lower energies (6 to 15 MeV) than higher energies (18 and 22 MeV). For 6, 9, 12, and 15 MeV, 89% of compared points were within 2% or 2 mm. For 18- and 22-MeV electron energies, 75% and 67%, respectively, were within 2% or 2 mm. These results are consistent with the recommendations of AAPM Task Group Report 53.  相似文献   
73.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
74.
Acute exposure to a neurotoxin, 3-nitropropionic acid (3-NPA), in rats results in an increase in total free fatty acid (FFA) concentration in selective brain regions. We investigated the effect of 3-NPA administration on the cerebral concentrations of FFA used as a marker of oxidative stress. Rats (n=3/group) were dosed subcutaneously (s.c.) either with a vehicle (phosphate buffer) or 3-NPA in phosphate buffer at 30 mg/kg body weight. Animals were sacrificed after 1, 2, 3, and 6 h of injection. Brains were then dissected into frontal cortex (FC), caudate nucleus (CN), and hippocampus (HIP). The concentration of total FFA increased from 130 to 300% within 1–2 h after 3-NPA injection in all brain regions when compared with the baseline level obtained from the control rats and taken as 100%. In CN, FFA returned to the baseline level within 3 h of treatment. However, in FC and HIP the concentration of FFA remained significantly elevated above the baseline until 6 h. The released FFA provide a substrate for free radicals formation. The results of this study suggest a role of oxidative stress in the mechanism of 3-NPA toxicity.  相似文献   
75.
用高速离心、分段盐析、亲和层析、超滤和阴离子交换层析法,从牛胎盘中分离纯化出一种肝细胞生长因子。结果表明,此因子的最终得率为0.005mg/g牛胎盘,其分子量约为99000u,它能强烈刺激原代培养大鼠肝细胞的DNA合成。提示利用自制的亲和层析凝胶,通过此提纯流程可以得到一种肝细胞生长因子。  相似文献   
76.
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.  相似文献   
77.
78.
选择性髂内动脉结扎与栓塞对盆腔血供的影响   总被引:5,自引:0,他引:5  
目的:旨在探讨选择性髂内动脉结扎与栓塞两种方法对盆腔血供的影响。方法:将两组犬在膀胱上动脉分支以下之髂内动脉分别行结扎与栓塞,对比观察两组膀胱创面出血、盆腔动脉造影及盆腔脏器组织学变化,以确定其盆腔脏器的血供情况。结果:①结扎组膀胱创面出血明显大于栓塞组;②结扎组髂内动脉侧支循环建立时间明显早于且数目多于栓塞组;③两组盆腔脏器均未见缺血坏死。结论:栓塞组阻断髂内动脉侧支循环的数目多于结扎组,故对盆腔血供的影响大于结扎组。避免髂内动脉阻断范围过广可减少盆腔脏器缺血坏死的机会。  相似文献   
79.
本文结合在工作中遇到的一些实际问题,阐述了妇科专用高频电刀的使用注意事项.  相似文献   
80.
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