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101.
It has been shown previously that the antero-inferior cortex is subjected to maximal tensile stress during a fall onto the
greater trochanter. We have recently shown that in cases of femoral neck fracture, cortical thinning and porosity is greatest
in the anterior and antero-inferior region of the femoral neck. To investigate whether this is due to increased remodeling,
we have quantified surface-based parameters associated with Haversian remodeling in femoral neck biopsies from women with
intracapsular hip fracture and post-mortem controls. Cryostat sections of chilled biopsies were reacted for either tartrate-resistant
acid phosphatase (TRAP) or alkaline phosphatase (ALP) activity. Proportions of active canals were determined in each quadrant
(inferior, anterior, superior, posterior) of the femoral neck. The biopsies were then embedded in methacrylate to permit histomorphometry
using Goldner’s and Solochrome sections. In the cases there was no significant increase in the proportion of canals undergoing
remodeling in the cortex as a whole (p = 0.846), but the regional distribution of remodeling was markedly different from that in the controls. In the anterior cortex,
the proportion of canals undergoing remodeling was increased by 56% (p = 0.0087); in contrast there was a relative decrease of 35% in the superior region (p = 0.0047). In the anterior cortex of cases there were 76% and 42% increases in the proportions of eroded (p = 0.019) and osteoid-bearing (p = 0.041) canals, respectively. In the superior region, the decrease in the proportion of remodeling sites was due to a marked
decrease in canals with an osteoid surface (51%; p = 0.0031). Covariance analysis with cortical porosity as the dependent variable showed that porosity was significantly dependent
on the regional distribution of eroded (p = 0.033) but not on the distribution of forming (p = 0.153) canals (R
2adj = 0.51). Cellular levels of TRAP and ALP were significantly elevated in the anterior region of cases compared with the
controls (TRAP 55%, p = 0.006; ALP 36%, p = 0.003). For the posterior and inferior regions there were no marked differences in cellular TRAP and ALP levels compared
with control values. These data show that the increased cortical thinning and increased porosity we have previously observed
in the anterior cortex in cases of hip fracture are associated with increased indices of Haversian remodeling. These findings
are consistent with the hypothesis that, in cases of hip fracture, remodeling imbalance in the anterior cortex is a continuing
process up to the time of fracture and is due to increased osteoclastic cellular activity associated with an osteoblastic
response that is inadequate to prevent bone loss.
Received: 16 November 1998 / Accepted: 17 February 1999 相似文献
102.
Morphological analysis of the cervical spinal canal,dural tube and spinal cord in normal individuals using CT myelography 总被引:3,自引:0,他引:3
To verify the conventional concept of developmental stenosis of the cervical spinal canal, we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of developmental stenosis of the cervical spinal canal was reasonable and acceptable. 相似文献
103.
目的总结了椎管内肠源性囊肿的临床特点、诊断和治疗.方法分析了8例椎管内肠源性囊肿的临床资料,并结合了文献加以分析探讨.结果8例中6例为儿童,男女之比为3:1,囊肿位于颈段3例,胸段例,颈胸交界2例,腰骶段1例.囊肿全切除4例,近全切除1例,部分切除3例,均取得了较好疗效.结论椎管肠源性囊肿是先天性良性病变,早期诊断及手术治疗是最好的选择. 相似文献
104.
目的探讨医用胶在根管治疗术中堵塞根管的密合程度及作用机制。方法应用显微镜、扫描电镜对医用胶根管充填材料和牙胶尖常规充填材料进行对比研究。结果医用胶根管充填材料在根管中质地均匀,根尖孔及根管壁充填密合。结论医用胶可以作为一种新型根管充填材料,应用于临床根管治疗术。 相似文献
105.
上颌磨牙近中颊根第二根管的定位 总被引:1,自引:0,他引:1
目的 通过对 77颗离体牙根管数目的检查 ,对近中颊根第二根管口 (MB2 )与近中颊根管口(MB)腭侧根管口 (P)的相对位置分布的规律进行观察分析 ,为临床治疗提供依据。方法 选择 77颗上颌离体牙 ,其中上颌第一磨牙 35颗 ,上颌第二磨牙 4 2颗 ,截冠后寻找近中颊根及其第二根管 ,并取得上颌恒磨牙根管口间距及根管口连线夹角等数据。结果 上颌第一、二恒磨牙近中颊根存在第二根管的有 36颗 ,占总数的 4 6 .75 % ,其中有1 5颗牙近中颊第二根管钙化不通 ,2 3颗牙近中颊根的第二根管口位于腭侧与近中颊第一根管口连线的近中处 ,近中颊根管口至近中颊第二根管口的距离为 1 .2 8± 0 .35 mm ,腭侧根管口至近中颊根管口的距离为 2 .98± 0 .4 7mm ,近中颊第二根管口至 P- MB线的垂直距离为 0 .6 3± 0 .1 2 mm,P- MB线与 MB- MB2 线的夹角为 2 5 .1 4°± 8.0 3°。结论 在上颌恒磨牙根管治疗时应注意根管系统的变异 ,改进开髓洞形 ,掌握查找近中颊根第二根管方法 ,以免遗漏根管 相似文献
106.
杨荣富 《现代中西医结合杂志》2004,13(13):1687-1688
目的 比较同种异体肾移植手术椎管内阻滞和静吸复合全麻的优缺点。方法 回顾性分析 2 0 0 3年 1— 8月我院器官移植中心所做的同种异体肾移植手术的麻醉 ,对符合条件的 38例患者进行比较。结果 2组间比较ASA分级 ,术中输液量 ,移植肾血流开放前收缩压、舒张压、心率、麻醉并发症 (仅包括硬膜外血肿或心功能衰竭 )和移植肾存活率无显著性差异 ,体质量和ICU停留时间有显著性差异 ,静吸复合全麻组比椎管内阻滞组体质量更重 ,ICU停留时间更长。结论 椎管内阻滞有时不能满足手术要求 ,能满足手术要求的椎管内阻滞 ,手术结束后循环功能较稳定 ,烦躁不安少见 ,手术后恢复较快 ;静吸复合全麻能更好地满足手术要求 ,尤其是体质量较大的患者 ,但在拔出气管导管前后可能引起血流动力学剧烈波动 ,甚至心功能衰竭 ,手术后恢复较慢 相似文献
107.
108.
Computer-aided 3-D reconstruction and measurement of the optic canal and intracanalicular structures
Traumaticopticneuropathyisavision threateningdisorder Autopsiesafterheadtraumahaveshownthattheopticnervesareoftendamagedmostseverelywithintheopticcanal 1 Althoughvariouskindsofmicrosurgicaldecompressionoftheopticcanalhavebeenadvocatedastheeffectivemeth… 相似文献
109.
目的 探索一种疗程短、疗效好、患儿及家长易接受的根管治疗方法.方法 选择需行根管治疗的患儿162例,常规根管清理,试验组用抗生素糊剂充填乳牙根管,对照组用氢氧化钙糊剂,比较两组疗效.结果 经1年随访观察,抗生素组和氢氧化钙组乳牙根管充填成功率差异无显著意义.结论 用抗生素糊剂一次充填乳牙根管疗程短、疗效好,值得临床推广使用. 相似文献
110.
Acquired recto-spinal fistula has been described elsewhere as a rare complication of colorectal malignancy and Crohn's enterocolitis.
We treated a young man who developed a recto-spinal fistula as a result of a high fall injury. The patient presented with
meningeal signs, sepsis and perianal laceration. Computerized axial tomography revealed air in the supersellar cistern. Gastrografin
enema showed that contrast material was leaking from the rectum into the spinal canal. Surgical management included a diverting
sigmoid colostomy, sacral bone curettage and wide presacral drainage. To the best of our knowledge, rectospinal fistula of
traumatic origin has not been previously reported in the English literature.
Received: 7 December 1998; Revised: 10 May 1999; Accepted: 10 May 1999 相似文献