边缘密度

Results: Of 23 mixed parotid tumor, all had well-defined margin and higher density than that of the normal parotid gland, 16 were round or elliptical in shape, the other 7 were lobulated.

结果：23例均表现为边缘清楚的肿块，圆形、卵圆形16例，分叶7例，密度高於腮腺，较均匀14例，不均匀9例。

Results There were 8 angiomyolipomas, 2 leiomyomas, 2 multilocular cystic nephromas, 1 hemangioma and 1 mesoblastic nephroma. Only multilocular cystic nephroma and leiomyoma have special characteristics that can be determined from RCC.

典型的平滑肌瘤和多囊性肾瘤在CT上有可与肾癌鉴别的特征性表现：平滑肌瘤为规则圆形，边界清楚，密度均匀，CT值略高于肾实质，无钙化，弱强化；多囊性肾瘤为边界清楚的包块，可见边缘锐利含多个分隔的肿块，分隔之间为囊腔，囊内容物的CT值与水相似或稍高，而错构瘤、海绵状血管瘤、慢性肾脓肿、中胚层肾瘤在CT上无法与肾癌鉴别。

The structural characteristic of the MNLs is corresponded with the feature of the water masses. The intrusion of the Kuroshio Current into the shelf sea, the turbid Changjiang diluted water mass and the interaction between the coastal current system and the Kuroshio Current shelf branches are responsible for the structural variety of the marine nepheloid layers in the East China Shelf Sea.

雾状层结构特征与以温、盐和密度为特征的海洋水团类型有良好的对应关系，黑潮在东海陆架边缘沿陆坡的爬升及其入侵陆架的支流与较浑浊的黄、东海陆架水体的相互作用，以及浊度较高的长江冲淡水在东海水体上层的存在，是东海雾状层类型复杂多样的主因。

2The difference of conventional X-ray and CT:results showed that CT was better than X-ray in depicting the signs such as density,lobulation,spiculate protuberance,mediastinum lymphaden,X-ray was better than CT in contour and edge of solitary globular lesion of the lung.

X线、CT表现差异：肿块密度、分叶、棘状突起、纵隔淋巴结肿大的观察CT优于胸片，病灶形态、边缘的显示胸片较CT优越。

The features including the marginal sign of cancer, such as lobular sign and spiculated sign, and the contrast-enhanced CT findings of sarcoma, such as rim enhancement and irregular low hypodense areas in the center.

既具有癌块的边缘征象，如分叶、毛刺等周边浸润征象，增强扫描又具有肉瘤的强化表现，如较厚的环状强化、肿块中央常为不规则的密度减低区。

Results Computer-assisted detection is useful to distinguish the malignant from the tumors. The sensitivity and specificity for mass by CAD system were 79.82%、55.20%. the character of mass, such as breast parenchymal density, mass shape, mass margins, mass density, spiculated, have especial affect on the CAD system, which is very similar to the distinguish malignant and benign from the tumors .

肿块密度、毛刺征、肿块形态、肿块边缘以及乳腺的腺体类型等这些影像学特征对CAD的诊断能力均有显著影响，P值均小于0.0001，而且其影响作用强度与肿块影像学征象对单纯肿块性病变的良恶性的诊断上有较好的相似性。

The PSC was a rounded or elliptic mass in the lung. It had rim enhancement and irregular low hypodense areas in the center after contrast-enhanced CT, lobular sign and spiculated sign.

肺内圆形或椭圆形较大肿块，增强扫描肿块呈不规则环状强化，中央显示不规则密度减低区，酷似肉瘤的CT表现，而其边界不甚规则，边缘不光整，有分叶、毛刺等浸润表现时应考虑为肺肉瘤样癌之可能。

Methods （1）310 patients of experimental group were performed with digital cine coronary arteriography,each of vascular edge of both the normal and the strictured segment was marked referring to the diameter of catheter,analysed the percentage of geometic stenosis,density contrast and stenosis length with computer.

（1）实验组310例完成数字电影冠状动脉造影后，以插入的导管管径为参照物，逐一标示正常段和狭窄段血管边缘，经计算机分析计算几何狭窄百分率、视频密度差异百分率和狭窄段长度。

Based on the regional tectonic evolution, combined with the high precision isotopic ages from this paper and other geologists, we have some new acquaintances as follows: 1 There has no Caledonian granite belt distributed in north margin of North China Craton. So, the traditional evolving model of North China Carton, which formed on this idea and the acquaintance about the collision of North China plate and Siberian plate, must be incorrect; 2 The age date show that the earliest magmatic activity began since late-Palaeozoic Permian, which is inconsistent with the previous idea that there were Caledonian and Hercynian active continental margin in the north of North China Craton and in the south Xingkai Massif. 3 the crust and lithosphere were thickened by the subduction and collision of Siberia plate and North China plate during Late Paleozoic. The magma is formed when the crust is heated and melts caused by thickened lithosphere delamination and caused the Asthenosphere upwelling. But only a little basaltic magma erupted, most magma underplate under the bottom of the crust. Thermal energy derived from basaltic magma underplating made the middle and lower crust melt partially and the late Permian-early Triassic granites is formed in large scale.

根据区域构造演化分析，并结合本文及他人高精度同位素年龄，我们对延边花岗岩形成的大地构造环境有了新的认识：1在华北地台北缘并不存在所谓的加里东花岗岩带，因此，建立在此之上的传统的华北地台北缘演化模式及有关西伯利亚板块与华北板块的碰撞拼合的认识也必然是不正确的；2华北地台北缘和兴凯地块南缘不存在加里东期和海西期花岗岩带，表明两地块边缘最早的花岗质岩浆活动始于晚古生代的二叠纪，即不存在传统观点所认为的加里东期或海西期活动陆缘；3晚古生代由于西伯利亚板块与华北板块的俯冲碰撞，致使地壳和岩石圈增厚，导致加厚岩石圈发生拆沉作用，使得软流圈上涌，加热地壳使之熔融形成岩浆，但玄武质岩浆少量喷出地表，大部分底侵于地壳底部，形成下地壳高密度的玄武质底侵层，玄武质岩浆底侵的热能引起中下地壳广泛部分熔融，形成大面积分布的晚二叠世—早三叠世花岗岩。

At the edges of the glass we are actually looking through a denser amount of material.

在玻璃的这些边缘实际上我们看到的是一个密度很高的材质。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。