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1.
颅面部的 CT扫描检查主要包括颅脑面部上、下颌骨、中耳、内耳、鼻窦、眼眍、眼球及颞骨茎突等部位的扫描检查 ,上述部位的扫描检查的位置的摆法 ,层面的厚度、间距 ,扫描时间及螺距等参数的选择及扫描后图像的后处理工作对检查结果的诊断至关重要。上述参数任意一个选择不当及  相似文献   
2.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
3.
本实验采用血管铸型扫描电镜,注射明胶卡红组织切片显微镜下观察和注射铅丹乳胶追踪血管来源三种方法对14只健康大白鼠肾上腺血管构筑进行了研究。大白鼠肾上腺动脉发自腹主动脉和肾动脉。它们在行程中发出分支至腺体表面,再次分支穿入囊内,逐级分支至毛细血管。皮质动脉发自囊内血管,它们在皮质中分支分布。球状带的毛细血管与囊的毛细血管相连,毛细血管在球状带围绕细胞团形成网眼状;在束状带呈放射状排列;在网状带吻合增多形成网状。髓质动脉亦发自囊的血管,它们在皮质中不发分支直抵髓质,在髓质分成毛细血管。网状带的毛细血管越向髓质口径越粗,它们在皮髓交界处互相吻合形成更粗的静脉,这些静脉逐级吻合,最后形成一主干——中央静脉,它穿出皮质出现于肾上腺门处。左侧的中央静脉注入在肾静脉,右侧的注入下腔静脉。  相似文献   
4.
Summary Modification of a type of end-to-side anastomosis that has been described before is studied. The recipient artery is occluded for only 3–4 minutes to complete the anastomosis by using only the running suture. The anastomotic site was studied by inspection and Scanning Electron Microscope (SEM) at different times after the operation on 30 rats.  相似文献   
5.
Radiologic evaluation of the skeleton and scanning electron microscopic studies of the teeth were performed on an infant boy with a lethal osteogenesis imperfecta (OI) syndrome who died at 10 mo of pneumonia. The skeletal findings included ribs that were focally expanded by fracture calluses, flat vertebral bodies, and wide limb bones. On fractured tooth surfaces, the enamel and dentin were normal as was the dentin calcification front. Although microscopic abnormalities have been noted in teeth from previously reported infants with lethal OI, a few studies also report infants with normal teeth. These differences in dental findings may indicate heterogeneity in OI lethal in infancy. Results of our study indicate that, until the primary biochemical defects in the OI syndromes are elucidated, examination of teeth from other infants with lethal OI and detailed evaluation of other clinical and skeletal features will aid in delineating heterogeneity and variation in expression in lethal OI.  相似文献   
6.
A rat model has been developed to compare relative morphological changes in the nasal mucosa after exposure to potential membrane permeation enhancers. Scanning electron microscopy was used to characterize gross structural and specific cellular changes following exposure. Micrographs of the rat nasal mucosa were scored in four categories: (1) mucosal surface integrity, (2) ciliary morphology, (3) mucus/extracellular debris, and (4) presence of red blood cells. The order of increasing morphological damage resulting from a 5-min exposure to each surfactant was 0.5% Solulan C-24 0.5% Solulan C-24/0.5% sodium tauro-24,25-dihydrofusidate (STDHF) < 0.5% STDHF < 1.0% STDHF 1.0% Laureth-9 < 1.0% sodium taurodeoxycholate 1.0% sodium deoxycholate. The changes observed in the mucosal morphology after exposure to the various surfactants are in general agreement with data in the literature. This model is able to compare rapidly the relative morphological effects on the mucosal membrane of different nasal formulations.  相似文献   
7.
Spherical isotropic fibre optic light diffusers are used in photodynamic therapy either as a light source or as a light detector. The construction of light diffusers using different materials is described, viz. an optical method involving local polymerization of a dental fissure sealant, which is referred to as the Henderson method, and a second method using plastic or ceramic pre-fabricated spheres. Quality tests necessary for reliable clinical use are presented for the mechanical strength, output power and isotropy. The maximum pull-off force and blow-off output power for the different kinds of diffusers were determined. The calibration procedures are given for measurement of the output power and wavelength of the light emitted by a diffuser and for measurement of the fluence rate by a light-detecting diffuser, using a compact integrating sphere device. With all types of diffusers described, an isotropy can be obtained of better than ± 20% measured over a 320° angle for spheres as small as 1 mm. Larger ceramic diffusers are particularly suitable for delivering high output powers. A 3-mm-diameter ceramic diffuser mounted on a 600-m-core fibre can emit up to 5 W of continuous wave (CW) visible light in air. Diffusers used for light detection can measure the light fluence rate in tissue with 15% accuracy or better if calibration factors are determined for each individual probe.  相似文献   
8.
目的探讨肺炎性假瘤的临床与X线误诊原因;方法依据临床与X线资料分析;结果均有不同程度的呼吸道症状,有14例痰中带血丝。肿块直径小于4cm11例,密度高而均匀,边缘光整,误诊为肺良性肿瘤。肿块直径大于4cm13例,密度不太均,边缘有分叶或有毛刺,误诊为肺癌;结论临床上多无急慢性感染症状,本病与其他占位性病变极相似,缺少特征,对本病缺乏认识是导致误诊的主要原因。肿块邻近胸膜,边缘出现尖角征,动态变化缓慢这3点对提高正确诊断率有独特的价值。  相似文献   
9.
Summary The uptake and localisation of O-(-hy-droxyethyl)-rutosides (HR) in the venous wall was studied in 8 patients undergoing crossectomy for a varicose long saphenous vein. The fluorescence of cross-sections of the vein wall was measured by laser scanning microscopy, based on the autofluorescence of HR. Four patients (treated group) received 2 × 1.5 g HR IV before surgery, and four (untreated patients) served as controls.Uptake of HR into the veins from treated patients was seen, with a mean fluorescence intensity of 80.9 units compared to 49.4 units in the untreated veins. The increase in fluorescence was clearly demarcated on the endothelial side of the vein wall.It is concluded that HR passes into the vascular wall, where it is localised in the endothelial and sub-endothelial areas.  相似文献   
10.
Summary In 11 mongrel dogs both kidneys have been subjected to a 2 h ischaemic period. One kidney was cooled by perfusing the renal artery at 4°C while the contralateral normothermic kidney was clamped for 2 h. Studying the renal blood flow using the Xenon wash out technique, sequential renal scanning and angiography, marked differences between hypo- and normothermic ischaemia kidneys were observed. One or two hours following hypothermic perfusion a marked decrease of blood flow in the first compartment and vasoconstriction was evident, while within this period following normothermic ischaemia an enhanced renal blood flow was observed. After 24 h renal blood flow and renal function tested by 131I-Hippuran clearance returned to normal values. Angiographic studies corresponded to the preoperative findings. In contrast, normothermic ischaemia kidneys showed a decreased renal blood flow, impairment of kidney function in isotope studies and pathological angiographic changes.Supported by Deutsche Forschungsgemeinschaft  相似文献   
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