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31.
目的:研究紧咬、叩齿运动中松动牙牙合力的动态变化特征。方法:选择19例单侧下颌第一磨牙松动的患者,用PVDF动态牙合力仪测量健侧和患侧下颌第一磨牙节律性叩齿和紧咬运动中牙合力动态变化曲线,分析最大牙合力峰值和到达峰值的时间,对两侧的测量结果进行分析。结果:叩齿运动中健侧下颌第一磨牙牙合力峰值平均为25kg,到达峰值的时间为108ms;患侧的分别为21kg和126ms;紧咬运动中健侧下颌第一磨牙牙合力峰值平均为27kg,到达峰值的时间为768ms;患侧的分别为23kg和1023ms;经配对t检验,健侧与患侧的峰值及到达峰值的时间差异均有显著性。结论:牙齿松动导致咀嚼功能降低,牙合力值和牙合力上升的速度均降低。  相似文献   
32.
胃幽门弯曲菌感染对胃癌发生影响的探讨   总被引:1,自引:1,他引:0  
应用Warthin-starry镀银技术检查胃幽门弯曲菌,对中国胃癌高发区及美国胃癌高发区新奥尔良检查了300例具有胃症状的胃粘膜标本。结果发现幽门弯曲菌阳性率为60~62%,并且看到这种细菌的感染与慢性胃炎病变的程度有明显的关系。本文探讨了幽门弯曲菌的感染与胃癌癌前病变的关系。  相似文献   
33.
Modifying potentials of various chemicals on tumor development were investigated in a wide-spectrum organ carcinogenesis model using male F344/DuCrj rats. The animals were treated with N-nitroso-diethylamine (100 mg/kg body weight, ip, single injection at the commencement of the study), N-methyl-N-nitrosourea (20 mg/kg body weight, ip, 4 times during weeks 1 and 2) and N-bis(2-hydroxypropyl)nitrosamine (0.1% in drinking water, during weeks 3 and 4) for multi-organ initiation and then were given one of 14 test chemicals including 6 hepatocarcinogens, 7 non-hepatocarcinogens and 1 non-carcinogen, or basal diet for 16 weeks. All rats were killed at the end of week 20, and the major organs were carefully examined for preneoplastic and neoplastic lesions. Immunohistochemical demonstration of glutathione S -transferase-positivc foci was also used for quantitative assessment of liver preneoplastic lesion development. Modifying effects were shown for 11 out of 14 test agents in the liver, forestomach, glandular stomach, lung, urinary bladder or thyroid, 7 of them targeting more than two organs. This was the first demonstration to our knowledge that cloflbrate possesses enhancing potential for urinary bladder carcinogenesis and an inhibiting effect on thyroid carcinogenesis. Caprolactam showed no effect in any organ, in agreement with its established inactivity. The results indicated that the system could be reliably applied as a medium-term multiple organ bioassay for assessment of the modification potential of test agents in unknown target sites.  相似文献   
34.
白质病变与血管性认知障碍的相关研究   总被引:1,自引:0,他引:1  
目的探讨白质病变与血管性认知障碍及其相关危险因素的关系,为血管性痴呆的预防、早期诊断和治疗提供理论依据。方法选择130例经影像学证实的白质病变患者,经简易智能状态检查量表(MMSE)评估分为认知障碍组和无认知障碍组,分别对白质病变部位和分级进行比较。结果室周病变、室周合并深部白质及弥漫性白质病变与认知障碍相关。结论白质病变对血管性认知障碍的发生有显著影响。  相似文献   
35.
A 50-year-old woman presented with a 5-year history of mild pain in her right knee, which had increased over the last 2 years. A palpable mass over the anterolateral aspect of the knee was obvious and the last 3 months she was experiencing locking episodes with consequent knee effusion. The differential diagnosis was driven between meniscal cyst, pigmented villonodular synovitis, synovial sarcoma, synovial chondromatosis, and aneurysm. After a diagnostic arthroscopy, the lesion was excised by a limited lateral arthrotomy. The pathologic findings revealed a synovial cyst. Intra-articular synovial cysts are uncommon, nonsymptomatic, and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. This lateral meniscus synovial cyst (2.5 × 2.5 cm) was enlarged within the intracondylar notch and produced disabling knee symptoms. The peculiarity of this lesion was the tumor-like appearance: its large size, the progress of symptoms, and the multilobulated, nonhomogenous signal on the MRI scan. One year postoperatively, the patient is asymptomatic and the MRI obtained at 6 months revealed no remnant of the fully excised cyst.  相似文献   
36.
Recent studies show comparable results of arthroscopic shoulder stabilization techniques compared with the gold standard open Bankart reconstruction. Great technical advances and ever-increasing surgeon experience have rendered pathology once deemed an indication for open surgery as treatable by arthroscopic means. With this movement toward a more universal application of all-arthroscopic techniques, we might consider the following question: Is there ever a need to open? To answer this question, we must first consider normal anatomy and then appreciate the contribution of deranged pathoanatomy to recurrent instability in each individual case. The surgeon must then determine whether this is best addressed via an arthroscopic or open technique. Arthroscopy, as compared with open stabilization procedures, holds the potential benefits of decreased morbidity rates, early functional rehabilitation, and improved range of motion. Despite potential advantages, arthroscopic stabilization is clearly contraindicated when a significant pathologic lesion contributing to recurrent instability cannot be adequately addressed as a result of the limitations of current techniques or instrumentation. On the basis of this principle, we believe that sizable glenohumeral bone defects remain the only absolute contraindication to an all-arthroscopic approach. Many complicating issues, such as attenuated capsule, humeral avulsion of the glenohumeral ligament lesions, cases of revision surgery, and collision or contact athletes, exist and warrant close attention. We prefer to think of these situations as “challenges” for which both arthroscopic and open surgery should be considered, rather than as true contraindications to arthroscopic shoulder stabilization. We are, by no means, advocating arthroscopic treatment in all cases of shoulder instability, because this would represent a gross oversimplification of the issues at hand. However, we do acknowledge that the steadfast contraindications to arthroscopic shoulder stabilization are decreasing every day.  相似文献   
37.
38.
Abstract We describe two cases of bizarre parosteal ostechondromatous proliferation (BPOP), commonly known as Nora’s lesion from the author who first described it, arising from the hands of two middle-aged patients. We emphasize the rarity of this lesion and the difficulty in diagnosis, since the histological pattern may mimic that of a malignant sarcoma.  相似文献   
39.
目的探讨肝移植术后缺血型胆道病变的再移植的指征、手术时机的选择及免疫治疗策略。方法回顾性分析我中心自1999年7月至2007年2月10例肝移植术后缺血型胆道病变再移植治疗的病例。供肝植入均采用改良背驮式原位肝移植术,手术当天及第四天给予IL-2受体拮抗剂(舒莱),术中不用激素冲击,术后采用他克莫司(FK506),麦考酚酸酯(MMF)和激素(Pred)的常规三联或FK506和MMF两联免疫抑制治疗方案。结果10例病人中8例术后肝功能恢复良好,顺利痊愈出院,最长已存活42个月。2例死亡,分别于术后34、69 d死于严重的混合感染。术前MELD小于25分的7例患者无一例死亡,术前MELD大于25分的3例患者中2例死亡。结论肝移植术后发生缺血型胆道病变行再次肝移植是有效的治疗方法。术前对患者病情的准确评估,尽可能在MELD评分小于25分时进行再次肝移植治疗,有助于提高再移植的疗效。  相似文献   
40.
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