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81.
应用双光子及单光子吸收测定技术,检测了92名出生3d内的新生儿骨矿质含量,其中巨大儿30名,正常体重儿32名,低出生体重儿30名,其孕龄分别是40.1±0.7、39.1±1.5和37.4±1.2孕周。结果表明,巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是101.6±28.8、85.2±19.8、59.9±27.2g/cm2,巨大儿骨矿质含量最高,正常体重儿次之,低出生体重儿最低,差异有显著性(P<0.01)。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性,相关系数分别是0.943、0.879和0.745(P<0.01)。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性,相关系数分别是0.755、0.596和0.556(P<0.01)。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量,肱骨是确定全身骨矿质含量较好的部位,新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。 相似文献
82.
An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 × 165 × 165 μm3 voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambigous results. 相似文献
83.
颞耳岩锥长轴方向的确定和应用 总被引:3,自引:1,他引:2
农俊彬 《右江民族医学院学报》1998,20(4):541-543
用头颅表面两个标志点确定岩锥长轴方向,指导梅氏(Mayer)位和斯氏(Stenvers)位摄影操作。对120例正常头颅CT图像进行测量,进行统计学处理,确定正常人岩锥长轴前延长线与头颅表面交点的大概位置。结果为:岩锥长轴前延长线交于对侧听眦线外眦后0.82~2.90cm区间,平均值左为1.66cm,右为1.82cm。结论,以平均值的邻值2cm为常数,即对侧听眦线外眦后2cm为岩锥长轴前延长线的前端体表定位标志,与其后端的乳突最突点共同确定岩锥长轴方向。 相似文献
84.
近3年来,用制备的胎骨充填良性骨肿瘤及病样病变术后骨缺损,经观察10例效果良好。胎骨因其自身组织学和生理学特点,具有抗原性小、诱导成骨活性高,利于“爬行各代”等优点。而且来源丰富、采制简单、储存容易、费用低度,是一种良好的植骨材料,特别适于儿童及年老体弱患者自身取骨困难的骨缺损植骨需要。但其为异体骨,有一定免疫原性,抗支撑强度略差,应注意严格无菌操作、消除免疫原性、配合使用内、外固定等措施。 相似文献
85.
I. V. Avdeev V. I. Seledtsov I. V. Prokopenko G. V. Seledtsova V. A. Kozlov 《Bulletin of experimental biology and medicine》1995,120(2):826-828
After separation of normal murine bone marrow cells in a Percoll density gradient cellular fractions with densities of 1.076
and 1.060 g/ml are capable of suppressing thein vitro growth of leukemia cells. The cytostatic activity of these fractions, however, does not surpass the level of antitumor antiproliferative
activity intrinsic to intact bone marrow cells. These cells were found to be capable of joining the splenocytes, thymocytes,
and lymph node cells in effector cytostatic cooperation and thus enhance the final antitumor effect.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N
o
8, pp. 181–183, August, 1995 相似文献
86.
A. Rashid Choudhury Mohamed S. Al Amin Kamal A. Chaudhri Khalaf R. Al Moutaery 《Child's nervous system》1995,11(2):115-117
A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma. 相似文献
87.
Summary
High-resolution computed tomography (HRCT) provides excellent contrast between osseous structures, air and soft tissue in
conjunction with high spatial resolution. Therefore, thin-section HRCT with bone window setting is the method of choice for
the examination of the middle ear structures. The indications are acute and chronic inflammatory changes, cholesteatoma and
tumor, the “postoperative middle ear”, and malformations. In most cases, HRCT enables differentiation between inflammatory
changes, cholesteatoma, and tumor. The excellent depiction of subtle osseous details enables the identification of erosions
of the ossicles or of the bony walls of the mastoid cells, of osseous defects of the tegmen, of the bony labyrinth, and of
the tympanic course of the facial canal. In addition, HRCT enables excellent depiction of reconstructions of the ossicles
or prosthesis of the ossicles. Although HRCT is the first method of choice, magnetic resonance imaging (MRI) may provide additional
information and lead to a more accurate diagnosis in some cases. This is explained by the excellent soft tissue contrast provided
by MRI. In addition, MRI offers the possibility of using various pulse sequences and the administration of IV contrast material.
Therefore, MRI may allow the differentiation between inflammatory changes, cholesteatoma, and tumor in those cases in which
accurate diagnosis cannot be made by HRCT. The differentiation between a meningocele or meningoencephalocele and other entities
such as tumors or cholesteatoma can be established by MRI. Furthermore, MRI can accurately depict cases of labyrinthitis or
of neuritis of the facial nerve or of intracranial disease caused by middle ear processes, while this is not always possible
by HRCT.
In summary, HRCT of the middle ear is the method of choice, but MRI may provide supplementary information in those cases in
which accurate diagnosis cannot be established by HRCT.
相似文献
88.
Masaki Hata Akinori Nango Hisateru Niki Yoshifumi Hayafune Atsushi Kato 《Journal of orthopaedic science》1997,2(1):3-9
To elucidate the growth of the tarsal bones in congenital clubfoot, relative to the growth of these bones in the unaffected feet and compared to growth in the feet of normal volunteers, we used a computed tomography (CT) scanner to measure the volume of all tarsal bones. The subjects of the study were 10 adults (7 men and 3 women) with unilateral congenital clubfoot (average age 20 years and 1 month). As controls, we examined 11 healthy volunteers. We calculated the ratio of the volume of each tarsal bone to the total bone volume and the ratio of the volume of each tarsal bone in clubfoot to the corresponding bone in the unaffected foot. The volume ratio of each tarsal bone was compared between clubfeet and unaffected feet because the differences of each tarsal bone ratio between the normal foot group and unaffected foot group were not significant. In the clubfeet (n=10), the talus and the medial cuneiform bones were smaller than those in the unaffected feet (n=10) but the cuboid bone was larger. The growth of the navicular did not differ from as that in unaffected feet. Our results suggested hypoplasia on the medial side of the foot in adult patients with congenital clubfoot. The 3 patients who had undergone medial release showed particularly marked hypoplasia of the medial side. In congenital clubfoot cases with severe deformities who had undergone wide soft-tissue release operations, there were clear growth suppressions in the talus and the medial cuneiform. We could not determine whether the cause of the growth suppression was the hypoplastic nature of tarsal bones themselves or the surgical obstacles to tarsal bone growth. 相似文献
89.
本文报告了自1985年 ̄1995年间采用带旋髂深血管蒂髂骨瓣移植与加压螺纹钉内固定治疗青壮年囊内型股骨颈骨折26例。随访时间平均5年5个月。结果,26例骨折痊愈,骨折愈合率为100%。骨折愈合时间平均4个月。仅1例骨折愈后后股骨头发生缺血坏死。股骨头缺血坏死率为4%。 相似文献
90.
带血管蒂舟骨瓣移位术的应用解剖 总被引:3,自引:0,他引:3
目的:为治疗距骨骨折提供新术式的解剖学基础.方法:在30侧灌注红色乳胶的成人下肢标本上,对舟骨背侧面形态、血供来源进行观测.结果:舟骨背侧面动脉主要来自内踝前动脉、跗内侧动脉以及足底内侧动脉浅支,分别发3~5支、1~3支和1~2支外径在0.2~1.0mm之间的骨膜支,形成骨膜动脉网.结论:以内踝前血管为蒂,可切取舟骨背侧2.0cm×1.0cm×0.5cm大小的骨瓣,用于距骨颈骨折修复.术式经临床应用证实,手术简便,效果可靠. 相似文献