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41.
Summary Racial and sex differences in the level of ending of the spinal cord of the adult have been reported. It is lower in Africans and in females. Since such differences may affect even fetuses and newborns we aimed to study in Northern Turkish neonates. The study was made on 40 full-term newborn still-births (23 male, 17 female). In all cases, the length of the vertebral column, the length of the spinal cord and the body weight were measured and the vertebral level of ending of the spinal cord was noted. It was found that the termination of the spinal cord varied from the first lumbar to the second sacral vertebra, with a mean level between L2 and L3. In female neonates, it was observed that the spinal cord ended at a slightly lower level (0.2 vertebra) than in males. Our findings approximately agreed with those of Barson [2] who studied neonates in England and of Jit and Charnalia [5] in North India. However, we found that the spinal cord ended one and half vertebrae lower in Northern Turkish neonates than in South African and South Indian subjects. The correlations between body-weight and length of the spinal cord, weight and length of the vertebral column, length of the spinal cord and length of vertebral column, length of the vertebral column and level of ending of the cord were statistically highly significant for males, females and both sexes together (p<0.001). The longer the vertebral column, the higher the termination of the spinal cord.
Niveau vertébral de la terminaison de la moelle épinière et sa relation avec la longueur de la colonne vertébrale chez le nouveau-né en Turquie du Nord
Résumé Selon la race et le sexe, les différences de niveau de la terminaison de la moelle épinière ont été rapportées chez l'adulte. Elle est plus basse chez les Africains et chez les femmes. Dès lors il se peut qu'il existe déjà des différences raciales et selon le sexe, chez le foetus et le nouveau-né. Nous nous proposons d'étudier une population de nouveau-nés du Nord de la Turquie. Cette étude est faite à partir de 40 nouveau-nés à terme, décèdes (23 garçons et 17 filles). Chez tous ces nouveau-nés, la longueur de la colonne vertébrale, la longueur de la moelle épinière et le poids ont été mesurés. Le niveau vertébral de la terminaison de la moelle épinière variait entre la première vertèbre lombaire et la deuxième vertèbre sacrée. Le niveau moyen de cette terminaison était situé entre L2 et L3. Chez les filles nouveau-nés, il était observé que la moelle épinière se terminait légèrement plus bas (0,2 vertèbre) que chez les garçons nouveaunés. Nos observations rejoignent celles de Barson [2] qui étudia des nouveaunés d'Angleterre et celles de Jit et Charnalia [5] qui étudièrent des nouveau-nés du Nord de l'Inde. Cependant, nous avons trouvé que la moelle épinière se terminait une vertèbre et demie plus bas chez les nouveau-nés de la Turquie du Nord que chez les nouveau-nés d'Afrique du Sud et d'Inde du Sud. La corrélation entre le poids des spécimens et la longueur de la moelle épinière; le poids et la longueur de la colonne vertébrale, la longueur de la moelle épinière et la longueur de la colonne vertébrale, la longueur de la colonne vertébrale et le niveau vertébral de la terminaison de la moelle épinière parmi les garçons, les filles, et dans les deux sexes, étaient statistiquement très significatifs (p<0.001). Plus la colonne vertébrale était longue, plus haute était située la terminaison de la moelle épinière.
  相似文献   
42.
经椎动脉的小脑淋巴管前淋巴系统   总被引:3,自引:1,他引:3  
王怀经 C-S.  JR 《解剖学报》1990,21(3):226-227
  相似文献   
43.
Summary We describe a case of a vascular mass arising secondary to a postoperative vertebral arteriovenous fistula mimicking recurrent cervical neurofibroma on CT in a patient with neurofibromatosis. Angiography was required for diagnosis. The recurrent tumor resolved following balloon embolization of the fistula.  相似文献   
44.
目的探讨在CT引导下经皮经椎弓根行脊椎肿瘤穿刺活检的价值。方法CT引导下选择最佳穿刺点、穿刺角度及深度并随时调整,以确保整个穿刺过程在病变的椎弓根内及椎体内完成。结果所有病例均未发生穿刺并发症。11例所取组织量可满足病理检查要求。1例取材量不足而未能得出满意诊断结果。结论CT引导下经椎弓根行脊椎肿瘤穿刺活检取材准确,操作安全可靠。  相似文献   
45.
椎弓根定位方法与置钉技术探要   总被引:1,自引:1,他引:0  
目的 通过X线平片分析关节突、横突及椎弓根间的相互关系,探讨上关节突作定位标志的临床价值。方法 常规X线正位片,测量L1~L5横突中轴线TA、两侧上关节突下缘连线AA与椎弓根中心点连线PC间的距离,〈1mm视为重叠。用AA组与上关节突外缘垂线的交点为进钉点,临床手术30例。结果 212例X线片共1060个腰椎,TA、AA与PC的重叠率分别为92.3%和90.2%(P〉0.05)。男女两组间TA(P  相似文献   
46.
The Pax-1 gene has been found to play an important role in the development of the vertebral column. The cervico-occipital transitional zone is a specialized region of the vertebral column, and malformations of this region have frequently been described in humans. The exact embryonic border between head and trunk is a matter of controversy. In order to determine a possible role of Pax-1 in the development of the cervico-occipital transitional zone we studied the expression of this gene in a series of quail embryos and murine fetuses with in situ hybridization and immunohistochemistry. Pax-1 is expressed in all somites of the embryo, including the first five occipital ones. During embryonic days 3–5 the gene is down-regulated in the caudal direction within the first five somites, whereas more caudally Pax-1 is strongly expressed in the cells of the perinotochordal tube. In 5-day-old quail embryos, the cartilaginous anlage of the basioccipital bone has developed and there is no more expression of Pax-1 in this region. The fusion of the dens axis with the body of the axis also coincides with switching off of the Pax-1 gene. More caudally, the gene is continuously expressed in the intervertebral discs of murine embryos and therefore seems to be important for the process of resegmentation. Quail embryos do not possess permanent intervertebral discs. Hyper- or hyposegmentation defects may be explained by an over- or under-expression of Pax-1 during development. We also reinvestigated the border between the head and trunk in chick embryos by performing homotopical grafting experiments of the 5th somite between chick and quail embryos. Grafted quail cells formed mainly the caudal end of the basioccipital bone. They were also located in the cranial half of the ventral atlantic arch, and only a few cells were found in the tip of the dens axis.  相似文献   
47.
目的:探讨含重组人碱性成纤维细胞生长因子(recombinant human basic fibroblast growth factor,rhbFGF)和重组人骨形态发生蛋白-2(recombinant human bone morphogenetic protein-2,rhBMP-2)骨水泥在骨质疏松性腰椎压缩性骨折(osteoporotic vertebral compression fracture,OVCF)患者经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)治疗的应用价值。方法:回顾性分析2018年1月至2021年1月收治的103例行PKP手术治疗的OVCF患者,男40例,女63例;年龄61~78(65.72±3.29)岁。受伤原因:滑倒33例,跌倒42例,提重物受伤28例。根据填充骨水泥不同分为3组:磷酸钙组34例,男14例,女20例,年龄(65.1±3.3)岁,填充磷酸钙骨水泥;rhBMP-2组34例,男12例,女22例,年龄(64.8±3.2)岁,填充含rhBMP-2的骨水泥;rhbFGF+rhBMP-2组35例,男14例,女21例,年龄(65.1±3.6)岁,填充含rhbFGF和rhBMP-2的骨水泥。比较3组Oswestry 功能障碍指数(Oswestry dysfunction index,ODI)、骨密度、椎体前缘丢失高度、伤椎前缘压缩率、疼痛视觉模拟评分(visual simulation score,VAS)及再骨折发生率。结果:所有患者获得12个月随访。3组术后ODI、VAS呈下降(P<0.001),骨密度增高(P<0.001),椎体前缘丢失高度、伤椎前缘压缩率呈先下降后缓慢上升趋势(P<0.001),rhbFGF+rhBMP-2组术后第1、6、12个月ODI、VAS均低于rhBMP-2组和磷酸钙组(P<0.05),术后第6、12个月骨密度大于rhBMP-2组和磷酸钙组(P<0.05)。rhbFGF+rhBMP-2组术后第6、12个月椎体前缘丢失高度、伤椎前缘压缩率均低于rhBMP-2组和磷酸钙组(P<0.05)。3组再骨折发生率比较差异无统计学意义(P>0.05)。结论:含rhbFGF和rhBMP-2骨水泥可更有效地增加OVCF患者骨密度,获得术后满意的临床和放射学效果,显著改善临床症状。  相似文献   
48.
Quantitative ultrasound (QUS) is emerging as a simple, inexpensive and noninvasive method for assessing bone quality and assessing fracture risk. We assessed the usefulness of a contact calcaneal ultrasonometer by studying normal premenopausal women (group I, n= 53), normal postmenopausal women (group II, n= 198), and osteoporotic women without (group III, n= 141) and with vertebral fractures (group IV, n= 53). The osteoporotic subjects had a T-score of the spine or hip neck bone mineral density (BMD) <−2.5 based on the local Chinese peak young mean values. When compared with postmenopausal controls, mean broadband ultrasound attenuation (BUA), speed of sound (SOS), and quantitative ultrasound index (QUI) were 26%, 2.1% and 25% lower in women with vertebral fractures (p all <0.005). The correlation coefficients between QUS parameters and BMD of the spine and hip ranged between 0.4 and 0.5. The ability of the QUS to discriminate between patients groups was determined based on the mean value of normal premenopausal women in group I. The mean T-score for women with fractures was −2.87 ± 1.02 for BUA, −2.54 ± 0.79 for SOS, −3.17 ± 0.70 for QUI, −2.65 ± 0.86 for L2–4 BMD and −2.53 ± 0.66 for hip neck BMD. After adjustment for age and body mass index, the odds ratio of vertebral fracture was 1.71 (95% CI 1.2–2.6) for each 1 SD reduction in BUA, 2.72 (1.3–5.3) for SOS, 2.58 (1.4–4.6) for QUI, 2.33 (1.6–3.3) for L2–4 BMD, 2.09 (1.37–3.20) for femoral neck BMD and 1.88 (1.34–2.92) for total hip BMD. The association between the QUS parameters and vertebral fracture risk persisted even adjustment for BMD. The area under the receiver operating characteristic curve for BUA for vertebral fracture was 0.92, for SOS, QUI, L2–4 BMD and femoral neck BMD was 0.95, and for total hip was 0.91. Received: 7 January 1999 / Accepted: 18 May 1999  相似文献   
49.
Summary Application of paraoxon into the left vertebral artery (8–80 g) or both the left and right vertebral artery (4–8 g) of the anaesthetized cat evoked dose-dependent depressor effects, whereas heart rate was not influenced significantly. Also after systemic administration of paraoxon (150–825 g·kg–1), while peripheral muscarinic receptors were blocked, depressor effects were still observed. Dose-response curves for the depressor response to paraoxon were established. Infusion of low doses of dexetimide via the vertebral artery prevented the hypotensive action of paraoxon. The distribution of this antimuscarinic drug in the brain was investigated. The depressor effect of paraoxon can be attributed to both a decrease in peripheral resistance and cardiac output. Decerebration and midcollicular transection were carried out in order to elucidate the site and mechanism of action. The depressor effect of paraoxon seems to be mediated by a central mechanism of action located within the lower brain stem.It is concluded that stimulation of muscarinic receptors in the pontomedullary region gives rise to the observed changes in haemodynamic parameters. Muscarinic receptors in the hypothalamus seem to be of minor importance for the hypotensive action of paraoxon.  相似文献   
50.
Although retrograde vertebral artery flow was described over 100 years ago, its relationship to symptoms remains unclear. We documented 43 patients who were found by duplex scanning to have reverse flow in the vertebral artery. Of this group, seven patients (16%) were found to have symptoms described as typical for the subclavian steal syndrome. Nearly one-third were asymptomatic. Of the remaining patients, 13 (30%) presented with nonhemispheric symptoms while nine (21%) had hemispheric symptoms. Nine patients had to and fro flow in the vertebral artery. This variant was not found in subclavian steal patients but correlated with nonhemispheric symptoms. During follow-up (mean: 19 months) none of the asymptomatic patients became symptomatic, and there were no strokes or stroke-related deaths. Surgical procedures which restored antegrade vertebral artery flow did not necessarily improve symptoms of posterior circulation ischemia. In some patients improvement in posterior circulation symptoms was noted following carotid endarterectomy. It is concluded that retrograde flow in the vertebral artery is, per se, a benign entity. Accurate selection of surgical candidates remains imprecise. It will require not only identification of vertebrobasilar disease but as yet undefined tests to assure symptoms are due to these stenoses.  相似文献   
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