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101.
Radiographic quantification of alveolar bone level changes   总被引:3,自引:0,他引:3  
The "random burst" theory has recently been proposed as an explanation of the pattern of periodontal disease progression. The theory predicts that the progression of bone loss at individual sites is not dependent upon previous bone loss and age. A longitudinal radiographic study was designed to test this hypothesis, and to describe the changes in bone level over 2 years in a group of 180 subjects (18-68 years of age) who were not under systematic periodontal treatment. The results indicated that 94% of the sites did not show significant changes in the alveolar bone level during the observation period. The mean annual bone loss for the total population was 0.11 mm. By regressing longitudinal bone loss upon age, it was shown that the rate of bone loss increased rapidly between 33 and 56 years of age while a different pattern was shown for the age intervals 18-32 and 57-68 years. Also, the rate of bone loss increased with increasing initial bone loss. This was less evident in the oldest age group. It was concluded that the progression of bone loss in the present material is consistent with a "burst" theory. However, the progression did not occur randomly with regard to previous loss of alveolar bone and time.  相似文献   
102.
In a review of cases of fibrous cartilaginous dysplasia of bone, five of fibrocartilaginous lesions were found to be different in clinical behavior and radiographic and morphologic features from the others. We have named these previously undescribed tumors fibrocartilaginous mesenchymomas with low-grade malignancy in the fibrous elements.Dr. Bertoni is a visiting surgical pathologist from the Servizio di Anatomia ed Istologia Patologica, Bologna, Italy  相似文献   
103.
目的 探讨股骨带锁髓内针治疗股骨干骨折的临床应用价值。方法 回顾我院74例带锁钉治疗股骨干骨折的临床资料。结果 74例股骨干骨折术后能早期负重,早期功能锻炼,均骨性愈合,关节功能良好。结论 股骨带锁钉治疗股骨骨折特别是复杂的股骨干骨折疗效满意,且并发症发生率较低,带锁钉的临床应用扩大了普通髓内针的适应证。  相似文献   
104.
105.
Soft tissue aneurysmal bone cysts (STABCs) are extremely rare extraosseous counterpart of aneurysmal bone cyst (ABC), with close resemblance to histo-morphologic characteristics of ABC. Here we would like to report a 13-year-old female patient, who presented with a large mass, occupying the entire left hemithorax. Patient underwent resection of the thoracic mass. On histopathological examination, it was found to be a soft tissue ABC. It is a very rare tumor and until date 28 cases have been reported in English literature, to the best of our knowledge. On review of the literature, we found this to be the first case of STABC reported in thoracic cavity. The objective of this case presentation is to provide information regarding clinical presentation, radiological and pathological features, and course of management for this rare disease. Soft tissue ABCs are a new class of tumors, so more extensive research is required to establish standard guidelines for their diagnosis and management, to yield better prognosis.  相似文献   
106.
107.
Introduction and importanceTrapezium, as a carpal bone positioned at the distal row, is often associated with other wrist injuries such as distal radius fracture. Isolated trapezium fracture, especially in a comminuted form, rarely occurs. There are only six reports of isolated comminuted trapezium fractures in the literature to the best of our knowledge.Case presentationWe present a case with an isolated comminuted trapezium fracture presenting pain in his thenar eminence and thumb motion limitation. He was treated by Open Reduction and Internal Fixation (ORIF) with the K wire pin.Clinical discussionWe searched the published related studies and summarized the signs and symptoms of patients presented with trapezium fracture. The most common presentation of trapezial fracture include pain/tenderness at the base of the first metacarpal bone, pain/tenderness at the snuffbox area and 1st digit motion limitation. The treatment options described in the literature for isolated comminuted trapezium fracture are also presented. Open reduction and fixation with pin is the most common treatment mentioned in the literature. The priority is restoring the scaphotrapezial and trapeziometacarpal joint congruency to save the 1st digit range of motion.ConclusionComminuted trapezial fracture may happen following either low energy (like our patient) or high energy trauma. This paper highlights the fact that even a comminuted trapezium fracture can be easily missed. Regardless of the trauma mechanism (high energy versus low energy trauma), a high index of suspicion and delicate work up would be necessary in order not to miss this type of fracture.  相似文献   
108.
运动对骨骼-肌腱界面愈合组织的影响   总被引:2,自引:0,他引:2  
利用纽西兰兔作体内实验,来分析手术后石膏固定,笼内活动,连续被动性活动三种不同的复健方法对肌腱-骨骼间界面愈合组织的影响。结果显示在术后第15天愈合组织所能承受的最大张力,笼内活动组为0.875kg,石膏固定组为2.014kg,是笼内活动组的231.52%,而连续被动性活动组为2.638kg,是笼内活动组的261.35%。石膏固定组虽有很高的张力,但关节内粘连也较多。  相似文献   
109.
臀上动脉深上支髂骨骺移植的解剖学研究   总被引:16,自引:1,他引:16  
目的 :为带血供的髂骨骺移植提供解剖学依据。方法 :在 40侧经动脉灌注红色乳胶的成人臀部标本以及 2侧儿童标本上 ,观测臀上动脉深上支的行程、分支及滋养支 ;选用 5 0块髋骨 ,观察髂骨嵴前外侧部的滋养孔。结果 :儿童臀上动脉深上支的分支、分布与成人相似 ,位于臀中肌深面和臀小肌上缘 (相当臀前线 ) ,循髂骨嵴弓形向前 ,达髂前上嵴 ,沿途分出平均 (4 .2± 1.1)支外径 0 .5~ 1.1mm的髂嵴支 ,分布髂嵴骨膜 ,并发细小分支进入滋养孔。从髂前上棘至结节区 ,在距髂嵴缘下方 2cm范围内 ,平均有(2 2 .4± 6.7)个滋养孔。结论 :以臀上动脉深上支及其分支为蒂 ,在髂嵴前部可切取带骺骨瓣 ,以修复长管骨骨骺缺损。  相似文献   
110.
Adipose tissue yields adult adipose stem cells (ASCs) in large quantities via less-invasive methods. These cells are of interest owing to their modulating properties and paracrine activities, which can be harnessed in regenerative medicine. Many studies on the use of rat fat tissue in an autologous animal model have been conducted; however, the different locations to obtain stromal vascular fraction of rat fat depots have not been fully characterized. The purpose of the current study was to identify optimal source of ASC from various locations of rat body. Animal experiments in vitro revealed that fat depots from cervical fat are an optimal ASC source. A high ASC yield facilitates subsequent studies on autologous transplantation in rats. The secondary objective was to compare the efficiency of osteoinductive media composition and evaluate of osteogenic potential of ASCs for seeding on scaffolds for bone repair. Scaffolds were assessed in vitro, using rat adipose stem cells and three-dimensional (3D) scaffolds comprising polycaprolactone (PCL) or polycaprolactone covered with tricalcium phosphate (PCL + 5%TCP). Seeded ASCs adhere to the surface and migrate to the scaffolds. Upon staining and determining alkaline phosphatase levels, PCL + 5%TCP scaffolds performed better than PCL scaffolds. Furthermore, growth factors such as BMP2 and FGF2 significantly increased ASC mineralization and induced osteogenesis (p?<?0.05). Our results may help select and develop pre-clinical animal model for confirming the use of ASC, alone or in association with appropriate biomaterials for bone repair.  相似文献   
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