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61.
Multiple theories have been discussed about the etiopathogenesis of congenital middle ear cholesteatoma (CMEC) and its specific site of origin. The intraoperative identification of the precise location of the keratinous mass is important to guarantee its complete removal, in order to reduce the risk of recurrence. This study proposes the tensor tympani tendon (TTT) as a possible site of origin of CMEC. All CMECs treated between 2013 and 2019 were reviewed. Only Potsic stage I lesions were included. Preoperative radiologic images were compared to intraoperative findings. Three removed TTT were sent for histologic evaluation. Seven patients were included (M:F = 3:4). Preoperative CT images were classified as type A in 2 cases (28.6%) and type B in 5 cases (71.4%). At intraoperative evaluation all CMEC sacs were found pedunculated on the TTT. The histologic examinations confirmed the connection between the cholesteatomatous sac and the TTT. According to the correlation of imaging, intraoperative findings and histology, we proposed that the TTT could be the primary site from which CMEC originates.  相似文献   
62.
63.

Introduction

In our study, the aim was to anatomically and histologically investigate the morphometric structures of the branches involved in the sural nerve and sural nerve formation.

Method

The study was conducted on 46 lower extremities of 23 fetuses which were obtained from Izmir Katip Çelebi University, Atatürk Training and Research Hospital, with ages from 18 and 32 gestational weeks, without any external pathology or anomaly. During the study period, the posterior-side skin dissection of the lower extremity was performed with the aid of a surgical dissection microscope initially, and the structures forming the sural nerve and the sural nerve were exposed and made visible. Afterwards, sections were taken from these structures for morphometric measurements and histological examination.

Results

The mean values and standard deviations of morphometric measurements obtained were determined. Separately, it was determined that there was no statistical difference between right-left sides and genders in morphometric measurements (p > 0.05). The sural nerve was determined to be differentiated into 4 types as A, B, C and D according to the way the nerve branches forming sural nerve join. In addition, differing characteristics pertaining to the sural nerve and branches were determined.

Discussion

We are of the opinion that the data obtained in our study will be of use to neurologists, orthopedists and clinicians engaged in this region during interventional procedures.  相似文献   
64.
丹参与骨碎补注射液防治激素诱发股骨头坏死的实验研究   总被引:9,自引:0,他引:9  
目的探讨丹参和骨碎补对激素性股骨头坏死的防治机理及其交互作用.方法选用家兔50只,随机分成五组:模型组、丹参组、骨碎补组、丹参 骨碎补组、对照组.8周后观察五组家兔血液流变学、脂代谢、股骨头组织学等指标的改变.结果与对照组相比,模型组股骨头疏松,易于凿切,血液粘度和血脂升高,骨小梁变细、稀疏,空骨陷窝率增高,髓腔脂肪细胞增多;而其余各组上述病变有不同程度的减轻,其中以丹参 骨碎补组病理改变最轻.结论①丹参、骨碎补均能预防激素所致的高粘滞血症和高脂血症;②骨碎补能提高血钙血磷,激活成骨细胞,提高股骨头的骨密度,能预防激素性骨质疏松;③两药在预防SANFH方面有协同作用.  相似文献   
65.
BACKGROUND CONTEXT: Partial removal of the nucleus has been shown to decompress herniated discs, relieving pressure on nerve roots and, in some cases, offering relief from disc pain. The nucleoplasty technique builds on earlier surgical approaches that helped validate the strategy of intranuclear tissue removal. Nucleoplasty, a new minimally invasive procedure using patented coblation technology, combines coagulation and ablation for partial removal of the nucleus pulposus to decompress the disc. PURPOSE: To determine if histologic changes of the intervertebral discs and surrounding tissues occur after nucleoplasty. STUDY DESIGN: A light microscopic study of intervertebral disc and adjacent neural tissues after disc decompression by nucleoplasty in pig cadavers. METHODS: Light microscopy was used to examine disc and neural tissues in two pig cadaveric specimens (T12 to sacrum). Nucleoplasty was performed by 1) advancing a radiofrequency wand to a predetermined depth in the disc (ablation), and 2) withdrawing the wand to the starting point (coagulation). Discs and adjacent tissues were removed from treated and nontreated segments, and examined under light microscopy. RESULTS: Histologic examination revealed no evidence of direct mechanical or thermal damage to the surrounding tissues. There was clear evidence of coblation channels with clean coagulation borders of the nucleus pulposus. Normal histologic findings of the annulus and end plate, with normal neural elements of the spinal cord and nerve roots at the level of the procedure, were observed. CONCLUSIONS: The histologic findings of this study suggest that the nucleoplasty achieves volumetric removal of target disc tissue without overt thermal or structural damage to the adjacent tissues. Further studies in live animals will be needed to assess the effects of nucleoplasty on the annulus, end plate and neural tissues under physiologic conditions, including assessment of cell viability.  相似文献   
66.
目的 观察兔异体冻干跟腱重建前交叉韧带(ACL)后移植物Ⅰ型及Ⅲ型胶原的表达.方法 应用兔异体冻干跟腱重建ACL,手术后3、12、26、52周取移植物,行组织学观察,并应用免疫荧光共聚焦技术(CLSM)检测移植物Ⅰ型及Ⅲ型胶原表达的平均荧光值.结果 术后52周,异体移植物组织形态与正常ACL基本一致;正常ACL细胞周围主要表达I型胶原(57.10±5.04),几乎不表达Ⅲ型胶原(6.09±1.34);术后3周,移植物Ⅲ型胶原阳性表达开始增加,12~26周达到高峰,移植后52周仍有Ⅲ型胶原阳性表达(13.17±2.26),与ACL比较差异有统计学意义(P<0.05);术后3周,移植物Ⅰ型阳性表达开始减少,12周后逐渐增加,52周Ⅰ型胶原阳性表达(52.69±2.76)仍与正常ACL比较差异有统计学意义(P<0.01).结论 异体跟腱重建ACL后,重建后移植物组织形态与正常ACL基本一致,但移植物胶原基质组成与正常ACL存在明显差异.  相似文献   
67.
人体肺静脉组织学观察12例   总被引:10,自引:1,他引:10  
目的 研究肺静脉的组织学特性 ,以探讨肺静脉触发性阵发性心房颤动的解剖学基础。方法 通过HE染色、Masson染色和α Smoothmuscleactin的免疫组化 ,对 12例非心脏原因死亡的尸检标本肺静脉进行组织学研究。结果 共分析肺静脉标本 4 7支 ,其中 4 5支肺静脉可见有左心房心肌的延伸 :心肌袖。上肺静脉的心肌袖明显比下肺静脉延伸的距离长 [左上肺静脉 (12 6± 3 6 )mm ,左下肺静脉 (5 7± 3 2 )mm ,P <0 0 5 ;右上肺静脉 (10 2± 4 7)mm ,右下肺静脉 (4 4± 3 0 )mm ,P <0 0 5 ],右下肺静脉口的直径明显小于其余的肺静脉 [分别为 (12 2± 1 8、15 2± 3 1、15 3±1 9、15 0± 1 2 )mm ,P <0 0 5 ]。肺静脉内心肌纤维集合成束 ,走行不规则、方向各异 ,心肌束在肺静脉同一周径上的分布不均一。结论 非心脏原因死亡的人体肺静脉存在心房肌的延伸即心肌袖 ,其心肌纤维分布不均匀 ,走行方向各异 ,可能是产生触发性阵发性心房颤动的解剖学基础。  相似文献   
68.
Yang CG  Yu YC  Chen JJ  Sun J  Guo YB  Luo KX  Zhu YF  Hou JL 《中华内科杂志》2005,44(9):648-651
目的通过大样本横断面回顾性调查,了解HBeAg(-)和HBeAg( )两类慢性乙型肝炎(CHB)患者临床相关因素的异同。方法对1686例CHB患者的住院病历进行回顾性调查,分析HBeAg(-)和HBeAg( )CHB患者ALT、HBV DNA定量、肝组织病理(炎症及纤维化)等指标的组内和组间差异。结果HBeAg(-)CHB628例,占37·3%;HBeAg( )CHB1058例,占62·7%。HBeAg( )组ALT、HBV DNA总体上均高于HBeAg(-)组。HBeAg( )组肝组织炎症及纤维化程度总体上均轻于HBeAg(-)组。结论目前我国CHB病例以HBeAg( )者占多数。无论HBeAg(-)或HBeAg( )CHB,肝炎活动在病毒复制活跃时均重于病毒复制水平较低时。HBeAg(-)CHB肝组织学损害重于HBeAg( )CHB。  相似文献   
69.
长期摄入过量碘大鼠甲状腺的形态学变化   总被引:11,自引:6,他引:11  
目的观察大鼠长期摄入过量碘甲状腺的形态学变化。方法选用Wistar大鼠给予不同剂量的碘化钾,分别于实验3、6、12月时处死观察甲状腺质量、组织学变化、阳性增殖细胞数量等指标。结果低碘组大鼠甲状腺明显肿大,呈小滤泡性增生,阳性增殖细胞显著增多。各高碘组甲状腺虽未发生肿大,但发生了明显的组织学变化,主要表现为胶质蓄积,大滤泡增多,同时存在小滤泡增生;在5倍和10倍高碘(5HI,10HI)组两种变化均可见到,但在50倍和100倍高碘(50HI,100HI)组滤泡增生变得明显,阳性增殖细胞亦明显增多,但不及低碘组。结论长期摄入过量碘使大鼠甲状腺发生了明显组织学变化,但仍不足以形成甲状腺肿大;在50HI和100HI摄入时滤泡增生变得明显,提示甲状腺存在促甲状腺激素(TSH)刺激。  相似文献   
70.
应用石蜡连续切片技术对兴义维蚋成熟幼虫(具鳃斑)消化道的组织学结构进行研究。其消化道由前肠、中肠和后肠等3部分组成。前肠分为咽、食道和前胃,口内侧上方内陷形成一对形状不规则的上唇腺,咽前段存在骨化食窦,食道内陷形成套管样前胃。中肠以4个大型胃盲囊为起点,根据肠壁细胞形态差异分为3个区域。后肠由幽门、回肠和直肠组成,回肠与直肠结构差异明显。4条马氏管从中肠与后肠的分界处分出。纺织腺形态特异。  相似文献   
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