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991.
Grainne McAvinchey Fay Maxim Barry Nix Jelena Djordjevic Rognvald Linklater Gabriel Landini 《The Angle orthodontist》2014,84(6):957
Objective:To investigate the perception of facial asymmetry in young adults to identify the amounts of chin asymmetry that can be regarded as normal and may benefit from correction.Materials and Methods:Three-dimensional (3D) images of 56 individuals of mixed ethnicity were obtained and used to produce average 3D images of male and female faces. Distortion was then applied to these average faces using a 3D graphics package to simulate different amounts of chin point asymmetry. Five observer groups (lay individuals, dental students, dental care professionals, dental practitioners, and orthodontists) assessed timed presentations of 3D images, rating them as “normal,” “acceptable,” or “would benefit from correction.” Time-to-event analysis was used to assess the level of chin asymmetry perceived as normal and beneficial for correction for each group.Results:The factors influencing the perception of facial asymmetry were the degree of asymmetry and the observer group. Direction of the asymmetry and gender of the assessed individual did not affect the perception of asymmetry, except in the 4- to 6-mm distortion range. The gender of the observer had no influence on perception. There were statistically significant differences in the amounts of asymmetry that the laypeople and orthodontists considered to be normal (5.6 ± 2.7 mm and 3.6 ± 1.5 mm, respectively; P < .001) and felt would benefit from surgical correction (11.8 ± 4.0 mm and 9.7 ± 3.0 mm, respectively; P = .001).Conclusions:Perception of asymmetry is affected by the amount of asymmetry and the observer group, with orthodontists being more critical. 相似文献
992.
EJ Griffiths R Kampa C Pearce A Sakellariou MC Solan 《Annals of the Royal College of Surgeons of England》2009,91(2):159-160
A case is discussed of the use of medical images from the internet to support claims of injury. There were several inconsistencies in both history and examination even prior to the presentation of the specimen radiograph from the internet. Clinicians are advised to be vigilant, to question histories that do not match with examination findings, to ensure that all radiographs are adequately labelled with patient-specific information and to look for radiographic inconsistencies such as the presence or absence of accessory ossicles. 相似文献
993.
A case report of a rapidly enlarging dermoid cyst over the anterior fontanel is presented. Our presentation demonstrates the
course of rapid enlargement of the tumor with radiological images, which were examined at birth and during the process of
the tumor enlargement. The literature is reviewed with respect to the nature of this tumor, especially to the relationship
of tumor enlargement.
Received: 1 November 1999 相似文献
994.
Pietro Rubegni Niccolò Nami Sara Poggiali Domenico Tataranno M. Fimiani 《Skin research and technology》2009,15(2):148-156
Background/purpose: Because the skin is the only organ completely accessible to visual examination, digital technology has therefore attracted the attention of dermatologists for documenting, monitoring, measuring and classifying morphological manifestations. To describe a digital image management system dedicated to dermatological health care environments and to compare it with other existing softwares for digital image storage.
Methods: We designed a reliable hardware structure that could ensure future scaling, because storage needs tend to grow exponentially. For the software, we chose a client-web server application based on a relational database and with a 'minimalist' user interface.
Results: We developed a software with a ready-made, adaptable index of skin pathologies. It facilitates classification by pathology, patient and visit, with an advanced search option allowing access to all images according to personalised criteria. The software also offers the possibility of comparing two or more digital images (follow-up). The fact that the archives of years of digital photos acquired and saved on PCs can easily be entered in the program distinguishes it from the others in the market. This option is fundamental for accessing all the photos taken in years of practice in the program without entering them one by one. The program is available to any user connected to the local Intranet and the system may directly be available in the future from the Internet.
Conclusions: All clinics and surgeries, especially those that rely on digital images, are obliged to keep up with technological advances. It is therefore hoped that our project will become a model for medical structures intending to rationalise digital and other data according to statutory requirements. 相似文献
Methods: We designed a reliable hardware structure that could ensure future scaling, because storage needs tend to grow exponentially. For the software, we chose a client-web server application based on a relational database and with a 'minimalist' user interface.
Results: We developed a software with a ready-made, adaptable index of skin pathologies. It facilitates classification by pathology, patient and visit, with an advanced search option allowing access to all images according to personalised criteria. The software also offers the possibility of comparing two or more digital images (follow-up). The fact that the archives of years of digital photos acquired and saved on PCs can easily be entered in the program distinguishes it from the others in the market. This option is fundamental for accessing all the photos taken in years of practice in the program without entering them one by one. The program is available to any user connected to the local Intranet and the system may directly be available in the future from the Internet.
Conclusions: All clinics and surgeries, especially those that rely on digital images, are obliged to keep up with technological advances. It is therefore hoped that our project will become a model for medical structures intending to rationalise digital and other data according to statutory requirements. 相似文献
995.
在伽玛刀治疗计划系统中,为了给三维重建提供直观的参考依据,要求准确地对体表、病灶和其他组织进行轮廓提取。针对目前该系统中以手工轮廓提取为主的现状,本文提出一种基于链码的轮廓提取算法对其进行比较改进,并给出断层扫描图像应用本算法的结果。结果表明本算法的使用提高了治疗计划系统中轮廓提取的自动化程度,并能满足精度要求。 相似文献
996.
Aim: The aim of this study was to determine whether color images can be used as mood stimulants. Methods: Color photographs of natural scenery were shown to an experimental group (n = 10), while the same images in black and white were shown to a control group (n = 10). The test subjects were healthy, adult volunteers who were exposed to psychosomatic stress in mental work rather than physical labor. To determine the effects of the color images, the levels of salivary chromogranin A (CgA) and salivary cortisol were measured as biochemical parameters, and the mood adjective score was examined as an emotional parameter before and after showing the subjects the images. The data obtained were statistically compared. Results: In the experimental group, the salivary CgA level decreased significantly after viewing the color images. In the control group, the salivary cortisol level increased significantly after viewing the black and white images. The changes in the salivary CgA and salivary cortisol values in the experimental group were significantly different from the corresponding changes in the control group. In the experimental group, after viewing the color images, the negative mean mood score decreased, and four subjects were shown to have had their mood changed to a more parasympathetically dominant state, as assessed by alterations in three or more of four stress parameters (CgA, cortisol, Multiple Mood Scale negative and positive factors). Conclusion: Color images might potentially change the mood of a viewer to a more parasympathetically dominant state. 相似文献
997.
Perceptual systems can be altered by immersing observers in environments with statistical properties that differ from those naturally encountered. Here we present a novel method for placing observers in naturalistic audio visual environments whose statistics can be manipulated in very targeted ways. We present the results of a case study that used this method. Observers were exposed to an environment where there was a novel statistical relationship between two simple, visual patterns in otherwise natural scenes. Exposure to this altered environment strengthened perceptual interactions between the two patterns. 相似文献
998.
999.
E. Persohn W. Seewald J. Bauer J. Schreiber 《Experimental and toxicologic pathology》2007,58(6):411-418
The purpose of this study was to establish and validate fully automatic measurement of cell proliferation on scanned images of rat cecum and colon. Tissue slides were taken from a 4-week mechanistic study and processed for BrdU immunohistochemistry. Four sections of the cecum and colon per slide were scanned with the Zeiss MIRAX SCAN and transferred to the Definiens eCognition Analyst LS5.0 system for evaluation. Two rule sets for automatic counting of BrdU-positive and negative nuclei from mucosal cells on the image tiles were created by Definiens, one for cecum, one for colon. For validation, manual counting of 16 randomly selected tiles from five different slides of colon and cecum was performed. Negative and positive cell nuclei were counted in each image tile by four different people. Comparison of results from manual counting with the automatic counting showed that the sum as well as single tile data and labeling index (LI) from automatic counting were within the range of manual counting results ±10%. Automatic counting included only cell nuclei within the mucosa whereas muscularis and lymphoid tissue as well as wrinkles from tissue preparation were excluded. In addition, two data sets from automatic counting of the same image tile were compared: (1) data where image tiles with incorrect detection of mucosa were excluded from further calculation of LI and area, and (2) data where no visual check was performed and all measurements were included. Results were very similar for both data sets. The necessity of the manual correction may therefore be doubted. 相似文献
1000.
目的探讨肾柱的声像图特征及超声误诊原因,以减少B超误诊率.方法对120例肾柱肥大的超声图像及检查结果进行回顾性分析.结果随机抽查的120例肾柱肥大患者:年龄〈50岁,约占84%,〉50岁,约占16%,男女性别及左右肾无明显差异,绝大部分位于肾的中极,多数在2 cm以下,一般不超过3 cm.结论肾柱肥大有一定的声像图特征,超声对其正确诊断有重要参考价值. 相似文献