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61.
中鼻道及其周围结构的解剖学观测   总被引:1,自引:0,他引:1  
目的 探讨临床上经上颌窦口进入上颌窦诊疗的途径。方法 在 40例成人尸体颅矢状切面上 ,对中鼻道、半月裂孔、上颌窦口及其周围结构进行解剖学观测及上颌窦口的探针插入试验。结果 中鼻道、半月裂孔的长度分别为5 6.3 6± 2 .5 8mm、2 1.46± 1.79mm ;40例中 ,2 8侧 (70 .0 0 % )的上颌窦口位于半月裂孔的中 1/3部 ;12侧 (3 0 .0 0 % )的上颌窦口位于半月裂孔的后 1/3部。上颌窦口的形态不一。上颌窦口的前后径为 3 .14± 0 .47mm。上颌窦口距鼻腔底部、鼻小柱的距离分别为 3 0 .41± 2 .85mm、49.5 2± 2 .3 7mm。鼻小柱到上颌窦口与到鼻腔基底面连线的夹角为 40 .2± 3 .7°。 3 7侧 (92 .5 0 % )的上颌窦口能用直径≤ 2 .5mm的探针穿过。结论 经上颌窦自然开口行上颌窦口穿刺是安全、简便和有效的一种诊治方法。  相似文献   
62.
端脑髓突的断面解剖学观测   总被引:12,自引:2,他引:10  
刘丰春 《解剖学杂志》1998,21(3):189-192
目的:通过对端脑髓突支数及其分支的研究,探讨端脑髓突与脑回的对应关系,指导脑回的医学影像学定位。材料与方法:随机采用30个颅脑标本,经CT扫描后锯切出相应断面,结合断面标本及其相应的CT影像表现对端脑髓突进行综合观测。结果:端脑髓突清晰而易于辨认,各髓突对应相应的脑回皮质。端脑髓突的支数在不同端脑层面上明显变化,但侧别差异无显著性意义。结论:只有熟悉端脑髓突的支数及其分支等情况,才能认准端脑髓突,  相似文献   
63.
对11个人心标本沿右心室流入道和流出道各壁长轴纵行切开,再将各壁横切为上、中、下3份,各份按1mm厚度逐层切开,观察其各层肌纤维方向的角度并绘成坐标图。结果表明,右心室流入、流出道游离壁的肌纤维方向由浅入深基本上是渐变的。流入道游离壁的下1/3和流出道的上1/3,浅中层与内层之间可有纤维方向的突变。流入道隔壁的纤维方向从右向左逐渐移行,偶在左、右室内膜面有方向的改变。流出道右室面的中上部有一纤维方向变动较大的层次。对右心室各壁肌纤维方向的排列特或、分层、功能及其临床意义进行了探讨。  相似文献   
64.
Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep. Received: 5 January 1998 / Accepted: 19 March 1998  相似文献   
65.
目的:为带血管神经蒂游离移植股薄肌提供解剖学基础。方法:对64侧成人下肢股薄肌的主要血管支配、神经来源、血管蒂长度和入肌部位等进行解剖学观察。结果:股薄肌的主要血管起于股深动脉占90.63%.神经支配为闭孔神经前支。入肌部位在股薄肌中上1/3交界处前缘深面。结论:股薄肌动脉、静脉、神经的行程较为衡定和集中.肌肉位置表浅,便于切取.是临床上理想的供肌。  相似文献   
66.
小牛胸腰椎解剖、生物力学研究及其临床意义   总被引:5,自引:0,他引:5       下载免费PDF全文
目的 测量小牛胸腰椎相关解剖数据并测试其生物力学性能 ,探讨其作为胸腰椎前路内固定模型的可行性。方法 采集 1周以内的新鲜小牛胸腰椎脊柱标本 2 0具 ,测量椎体及椎间盘的最大横径、矢状径和前部高度。测试屈曲、伸展、侧屈及扭转状态下的载荷 -应变、载荷 -位移关系以及最大载荷时的应力强度及轴向刚度 ,并进行极限力学性能测试。结果 小牛胸腰椎椎体及椎间盘矢径、横径、高度自T10 至L5逐渐递增 ,椎体横径与矢径之比约为 1∶1,其T10 ~L5段椎间盘高度之和与椎体高度比值为 1∶0 .9。小牛胸腰椎载荷 -应变及载荷 -位移关系呈线性变化 ,生理载荷下屈曲、伸展及侧屈状态下的应力强度分别为 (2 .86± 0 .2 4 )N/mm2 ,(2 .17± 0 .2 0 )N/mm2 ,(5 .2 9± 0 .5 0 )N/mm2 。屈曲、伸展、侧屈及扭转状态下的轴向刚度分别为 (37.13± 4 .30 )N/mm ,(35 .38± 4 .2 0 )N/mm ,(34.5 6± 4 .2 0 )N/mm ,(5 1.6 9± 1.6 2 )N/mm。结论 小牛胸腰椎形态及大小可满足前路内固定模型的需要 ,以小牛标本作为体外非破坏性生物力学实验模型具有可行性。  相似文献   
67.
High spectral and spatial resolution (HiSS) MR data were acquired at 1.5 T using echo-planar spectroscopic imaging from patients with suspicious breast lesions. The water resonances in small voxels are inhomogenously broadened and often have distinct components. Images were calculated with intensity proportional to the Fourier components of the water resonance in each voxel at different offsets from the peak frequency. The results demonstrate that in breast the off-peak Fourier component images of water are qualitatively different from those derived from the peak height of the water resonance. These differences most likely reflect underlying anatomy or physiology. In conventional images, the superposition of the various Fourier components of the water signal may cause loss of detail. The synthesis of water Fourier component images from high spectral and spatial resolution data may provide a new form of contrast, and increase sensitivity to subvoxel physiology and anatomy.  相似文献   
68.
腓肠内外侧血管解剖特点及其在小腿创伤修复中的意义   总被引:3,自引:0,他引:3  
目的:为小腿创伤皮瓣移植修复与腓肠内、外侧血管吻合提供解剖学基础。方法:在70侧成人下肢标本上解剖观测了腓肠内、外侧血管的长度、外径、血管神经的毗邻关系及其形态特点。结果:①腓肠内、外侧动脉起于动脉,伴行静脉注入静脉;②动脉起点至入肌段的长度内、外侧分别为4.1±0.7(1.8~6.4)cm、3.7±0.5(2.0~6.5)cm;③肌门处内、外侧动脉的外径分别为2.2±0.1(1.1~3.4)mm、2.0±0.1(0.9~3.1)mm;④肌门处伴行静脉有1~2条,内、外侧静脉外径为2.5±0.3(1.8~4.5)mm,2.3±0.3(1.5~4.1)mm。结论:腓肠内、外侧血管恒定、径粗、较长,是小腿创伤皮瓣移植修复受区可供应用的吻合血管  相似文献   
69.
Objective To study the anastomotic relationships of perforators in each zone of the poste-rior leg and design perforating flaps for clinic. Methods Six fresh cadavers underwent a whole body, intra-arterial injection of a lead oxide and gelatine preparation. The posterior part of leg is divided into upper, mid-die and below equal parts, Observe topography of the perforating branches in every district by layer, and mea-sured their location, diameter, course, branches and anastomosis pattern. Radiographs of tissue specimens were digitally analyzed. Results There were 13 perforators that diameter≥ 0.5 mm, the average external diameter was 0.8 mm. The areas of each perforator supplied was average 38 cm2. Perforators from popliteal artery was identified an area 4 cm wide, around the intersection of two lines, a line drawn between the medial and lateral epicondyles of the femurs, and the midline of posterior leg. The areas of the every perforator sup-plied was 55 cm2. These vessels were large in diameter and create multiple true anastomoses with the perfora-tors from the posterior tibial artery or fibular artery. Perforating branches were small in the below part, a long perforator chain comprised of two to three perforators accompanies the Achilles tendon. Conclusion The perforator flaps deviced by perforators from the posterior leg may be transplanted to the lower limbs and the other part of the body. The perforators located in the middle zone of the leg are larger. Free posterior tibial or peroneal perforator-based flaps are reliable, relatively large, and have thin flaps. The upper and lower zones were the larger donor site for the proximal or distally pedicled perforator flap harvest.  相似文献   
70.
Glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein found in mature astrocytes. Although the exact function of GFAP is poorly understood, it is presumed to stabilize the astrocyte’s cytoskeleton and help in maintaining cell shape. Previous studies from our laboratory have shown that when astrocytes were cocultured with primary Schwann cells (pSCs), astrocytes became hypertrophied and fibrous with intensely positive GFAP staining and segregated Schwann cells (SCs) into pockets. In order to understand the functional role of GFAP in this already established astrocyte-SC coculture model, we generated GFAP-negative cell lines from a GFAP-positive astrocytoma cell line and cocultured both the cell lines with pSCs. Our studies demonstrate that the GFAP-positive cell line put out processes toward the SCs, whereas the GFAP-negative cells did not form processes and the majority of the cells remained round. The most significant and interesting finding of this study, however, is the formation of elaborate processes by SCs when grown in coculture with the astrocytoma cells, unlike SCs cultured alone, which showed their typical bipolar spindle-shaped morphology. The extent of processes did not seem to be dependent on GFAP, since SCs cultured with both the cell lines formed similar processes. This coculture model may be useful in elucidating the factor(s) responsible for the formation of processes by SCs and can be further help in our understanding of the mechanism of morphological transformation of SCs.  相似文献   
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