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1.
本文对 Eofletcheria minima Lin et Chow 分类位置重新修订,把该生物以动物界珊瑚动物门类中转移到植物界红藻门类里,并定名为 pseudoeofletcheria minima(Lin et Chow)Comb.nov.;同时认为生物化石分类的鉴定质量,对古生态的研究程度所做出的质量有重要的影响,同样古生态学的研究亦有助于重新去思索和确定一些生物化石的分类归属位置。  相似文献   
2.
目的 探讨颈椎间盘病变的CT平扫诊断与临床的价值。材料与方法,对80例颈椎间盘病变的CT表现按节段,类型,程度进行分析。结果:外伤是导致椎间盘病变的主要因素;颈椎间盘膨出和脱出均较少见,以突出为主;单节段发生较少,多节段发生常见,以C5/6,C4/T,C6/7多见;突出程度多在2-5mm之间。结论:CT检查能显示颈椎间盘病变的节段,类型以及与脊髓和神经根的关系,为临床制定治疗方案提供影像学依据。  相似文献   
3.
赤缸Dasyatis akajei(Muller&henle)隶属于软骨鱼纲,下孔总目,鲼形目,魟科,魟属,常栖息于底质为泥沙的深潭中。赤魟肉性昧甘、咸平,有补气之功效。用其熬油,主治小儿疳积。尾刺研末入药,对治疗胃癌、食道癌、肺癌、乳腺炎、咽喉炎、疟疾、牙痛、魟鱼尾刺刺伤均有一定疗效。赤魟尾刺含有多种毒素,有重要药理作用。涂洪斌等克隆出编码赤魟肿瘤抑制因子IPL的全长cDNA序列,并报道了赤魟亲环素A的融合表达、纯化及活性特征。  相似文献   
4.
本文报道157例经CT诊断的颈椎间盘突出,4例经手术证实。CT特征表现为:①颈椎间盘后缘局限性软组织块影疝入椎管出;②椎管与硬脊膜间脂肪间隙消失;③硬膜囊受压后移或压迫神经根管。  相似文献   
5.
本文报告200例经CT诊断的腰椎间盘病变其中10例经手术证实。本组CT诊断的准确率为90%。CT主要表现有:①椎管与硬膜囊之间的脂肪层消失;②腰椎间盘后缘局限性软组织块突入椎管;③硬膜囊和/或神经根受压;④突出髓核的滑移;⑤椎间盘突出部分钙化或骨化。另外,还可显示黄韧带肥厚、椎管或侧隐窝狭窄以及真空征等。  相似文献   
6.
本文探讨引起腰神经通道异常的原因和CT影像特征。本文采取的材料和方法为回顾性分析89例下腰部腰神经通道异常病例,包括85例退行性病变和4例造先天性的病例。结果是CT明确显示各种异常原因,如椎间盘突出,软骨结节,骨质增生,小关节突异常,黄韧带肥厚,椎板畸形等。从而得出CT诊断这类异常是极其有效的检查手段。  相似文献   
7.
目的:本文探讨了CT对腰椎小关节综合征的诊断价值,材料和方法:搜集100例腰椎小关节综合征,男70例,女30例,回顾性分析了CT表现,结果:CT表现,腰椎小关节骨质增生肥大骨赘形成,腰椎小关节间隙狭窄侧隐窝狭窄,关节面骨质硬化边缘骨质缺损表面毛糙,腰椎小关节不对称,部分病例出现小关节半脱位及关节腔真空征,腰椎小关节角增大。结论:CT可充分显示腰椎小关节的解剖及病理改变,为腰椎小关节综合征诊断提供可靠的影像学根据。  相似文献   
8.
Close range photogrammetry has been recognised as an essential tool for the capture of high-accuracy spatial data for medical applications, in particular work involving dynamic human body parts such as limbs. Offline and online photogrammetric systems are readily available for a number of common applications. However, off-the-shelf systems are not always appropriate because of project site conditions. To achieve high measurement accuracy in a field environment, a modified field camera calibration technique was introduced. The technique is particularly important where each camera is limited to one captured image during calibration, as the camera and the calibration testfield are in fixed positions. In this paper a custom-built imaging system designed for the study of the human spine in an outdoor environment is introduced. The discussion addresses: (1) imaging system design; (2) modified field calibration techniques; and (3) a case study on human spines. Two field camera calibration techniques were evaluated, both of which improved the accuracy of the prototype system, the use of a detachable target board offering the best results. This modified camera calibration procedure has improved the 3D measurement accuracy from 1·25 ± 0·3 mm to 0·43 ± 0·1 mm. The improvement is at a level achievable in the laboratory. The technique is considered to provide accurate and reliable anthropometric landmark measurement at low cost. This was evaluated in a clinical setting where diurnal changes in spine length and contour were measured in a cohort of 30 university students. The capability of the technique to measure sagittal and frontal angular changes provides a novel way of examining changes in spine shape.  相似文献   
9.
文中详细描述了云南东部地区早寒武世关山动物群中的典型分子Tuzoia sinensis Pan,对其形态特征做出了补充,通过与相关种的比较与讨论,对其鉴定方法做出了进一步探讨,并基于对壳体表面网格密度的研究推测了T.sinensis的俯视形态图。研究发现:T.sinensis的侧脊上分布有一系列锥状突起,这些突起的表面具有与壳体表面相同的网状纹饰,这提示Tuzoia侧脊上的基部宽大的三角形刺(frills)即由这种锥状突起侧压保存而形成;研究还发现:T.sinensis的三角形刺较其它种更为发达,其壳体在保存过程中易产生形变,但多而发达的三角形刺受后期改造影响较小,因而建议可以将其作为T.sinensis的典型鉴定特征之一而区别于其它种。  相似文献   
10.
This study investigates the effect of different Mediterranean habitats on spine and gonad colouring and gonadal index in the purple sea urchin Paracentrotus lividus (Echinodermata: Echinoidea). Specimens were collected in winter 2012 in Posidonia oceanica meadows and rocky bottom areas at two sites in Southern Sardinia (Italy, Tyrrhenian Sea). Colorimetric analyses of spines and gonads were conducted with a digital colorimeter using CIELAB colour spaces, which defines the colour in terms of three coordinate values: lightness (L*), redness (a*) and yellowness (b*). Lightness and redness of the spines differed significantly between habitats, whereas colour spaces of the gonads did not. A careful analysis of the gonad index showed it to be significantly affected by habitat, registering higher values in rocky bottom locations. In conclusion, it seems that habitat does affect spine colour but not gonad colour. Spine colour seems to be site‐dependent, whereas the gonad index depends solely on the habitat.  相似文献   
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