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排序方式: 共有552条查询结果,搜索用时 15 毫秒
1.
姜泊 《南方医科大学学报》2002,22(5):385-387
应用常规内镜技术难以发现大肠平坦型病变和凹陷型病变。近年来染色内镜和放大内镜技术已经发展成熟,在国外已获广泛应用,可以发现大肠微小病变和早期大肠癌。应用腺管开口分型方法可以预测肿瘤病变的组织学类型及肿瘤的浸润深度,据此可确定行内镜下粘膜剥离术或分片粘膜剥离术将肿瘤切除,抑或行外科手术治疗。在当前我国的胃肠内镜医疗界,应广泛开展染色内镜和放大内镜的临床应用,以早期发现大肠病变,提高我国大肠癌的内镜诊治水平。 相似文献
2.
改良上颌平面导板矫正青少年深覆颌的临床观察 总被引:1,自引:0,他引:1
目的观察改良上颌平面导致矫正青少年深覆颌的效果。方法制作上颌平面导板,下颌双侧尖牙与其接触,后牙抬高3.0 mm。分为昼夜戴用导板及仅夜间戴用导板两组,观察疗效。结果深覆颌总矫正率72.2%,昼夜戴用该改良上颌平面导板组的深覆颌矫正率100%。结论改良上颌平面导板制作简单,戴用方便,效果明显。 相似文献
3.
Yasushi Sano Hirohisa Machida Kuang‐I. Fu Hiroaki Ito Takahiro Fujii 《Digestive endoscopy》2004,16(Z1):S93-S96
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. 相似文献
4.
骨膜间质干细胞移植时机的实验和临床研究 总被引:2,自引:2,他引:0
目的 研究骨膜间质干细胞异体移植时机。方法 根据骨缺损内纤维组织生长时间的不同,将从大鼠骨膜分离培养的细胞分别分批植入,在植入的第2、3、4和8周时动态观察其成骨量,即骨小梁体积比;另将幼儿骨膜间质干细胞悬液,移植于26例长管状骨干骨折2周后的缺损内,观察骨折临床愈合的时间。结果 大鼠骨缺损后2周以内移植干细胞其骨小梁体积比大,愈合快,2周以后与对照组比无显著差异;临床应用9个月内病人骨折缺损愈合15例(57.7%),骨不愈合者11例(42.3%)。结论 大鼠骨缺损2周以内移植干细胞其疗效好,大鼠实验和临床上骨缺损2周以后移植骨膜间质干细胞不能明显促进骨缺损愈合。 相似文献
5.
TAKASHI OKI M.D. NOBUO FUKUDA M.D. TOMOTSUGU TABATA M.D. ARATA IUCHI M.D. MASATO TANIMOTO M.D. KAZUYO MANABE M.D. YOSHIMI KAGEJI M.D. MIWA SASAKI M.D. SUSUMU ITO M.D. 《Echocardiography (Mount Kisco, N.Y.)》1995,12(4):351-358
Transesophageal echocardiography was conducted to determine the systolic pattern of the anterior mitral leaflet in patients with flat chest, and to differentiate it from that associated with mitral valve prolapse. The fronto-sagittal index (an index of chest flattening) was determined in 50 subjects using chest radiographs, and was used to classify them into a flat chest group (index < 0.38, n = 28) and a normal chest group (index ≥ 0.38, n = 22). We then used transesophageal echocardiography to examine the anterior leaflet in these subjects. A significant positive correlation was observed between the fronto-sagittal index and the short-to long-axis diameter ratio of the left ventricle in all patients. These parameters, and the left atrial dimension were lower in the flat than the normal chest group. The clear zone area of the anterior leaflet during mid-to late-systole was significantly larger in the flat chest group. However, no intergroup differences existed in the rough zone area of the anterior leaflet or in the middle scallop area of the posterior leaflet. Mitral regurgitation was observed in 20 and 12 subjects in the flat and normal chest groups, respectively. The maximum mitral regurgitant area did not differ between the two groups. The clear zone area of the anterior leaflet increased significantly following inhalation of amyl nitrite in 22 subjects of both groups, but the other areas did not increase. The mitral regurgitant area decreased or disappeared after amyl nitrite at a similar rate in each group. Thus, the decrease in the antero-posterior dimension of the thorax in subjects with flat chest affects the systolic pattern of the clear zone of the anterior leaflet more than that of the rough zone of the anterior leaflet or the posterior leaflet. This systolic pattern in such patients differs from that associated with mitral valve prolapse. 相似文献
6.
A five generation family with type 4 preaxial polydactyly is reported. The 21 affected individuals demonstrated variability in expression without apparent sex influence and penetrance which was complete. The deformities were more severe in the feet than the hands. Anteroposterior flatness of the thumbs was the only manifestation of the trait in the hands of several affected family members. 相似文献
7.
Hologic FD原理浅析及维护 总被引:1,自引:1,他引:1
本文浅析了FD(平板探测器)的成像原理,探讨空间分辨率的计算方法,并对DR的使用环境,日常维护、维修作了介绍。 相似文献
8.
Age‐ and sex‐associated morphological variations of metatarsal torsional patterns in humans
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Masateru Kitashiro Naomichi Ogihara Tetsuro Kokubo Morio Matsumoto Masaya Nakamura Takeo Nagura 《Clinical anatomy (New York, N.Y.)》2017,30(8):1058-1063
It has been demonstrated that the torsional patterns of the metatarsal heads are associated with the presence or absence of the medial longitudinal arch in hominoid feet. The relatively untwisted second metatarsal is unique in humans, but that of the African apes is much more inverted, suggesting that the torsion of the second metatarsal might represent the overall shape and flatness of the foot. Some clinical studies have recently argued that the onset of foot pathologies such as hallux valgus might be related to the torsional pattern of the metatarsals. However, to date, no studies have systematically investigated the morphological variations of the torsional patterns of human metatarsals. In this study, therefore, the aim was to clarify the age‐ and sex‐associated variations in the torsional patterns of human metatarsals using three‐dimensional computed tomography. The torsion angles of the five metatarsals were calculated by defining the dorsopalmar vector of the metatarsal base and the vector corresponding to the rotational axis of the metatarsal head. The present result demonstrated that the second metatarsals of females were significantly more inverted with increasing age. Flat foot is known to be most common in elderly women. Whether there is a cause–effect relationship between second metatarsal torsion and flattening of the medial longitudinal arch has yet to be answered, but this study suggested that torsion of the second metatarsal might possibly be used as an indicator for the early diagnosis of flat foot and associated foot pathologies. Clin. Anat. 30:1058–1063, 2017. © 2017 Wiley Periodicals, Inc. 相似文献
9.
《Journal of cranio-maxillo-facial surgery》2014,42(1):e1-e7
BackgroundThe long-term goal of cleft palate repair is to provide normal maxillary growth and speech capacity. However, most surgical repairs of cleft palate result in areas of bone denudation on lateral aspects of the hard palate. It is widely acknowledged that palatal bone denudation and subsequent scar contracture resulting from cleft palate surgery can inhibit maxillary growth.MethodThis study is designed to investigate the effect of the periosteum on growth patterns of the maxilla. A total of 32 three-week-old Sprague-Dawley rats were randomly divided into a control group and three experimental groups: a mucosa excision group, a mucosa-periosteum excision group and a periosteal graft group. Nine weeks postoperatively the skulls were prepared for study and palatal widths and lengths were determined. The experimental groups were investigated for various histological changes.ResultsThere was no statistically significant difference for the maxillary measurements (palatal width and length) between the mucosa excision group and the periosteal graft group when compared with the control group. However, the mucosa-periosteum excision group compared to the control indicated a statistically significant decrease in the same measurements. There was also a statistically significant difference for the maxillary measurements between the periosteal graft group and the mucosa-periosteum excision group.It was demonstrated histologically that the density of the Sharpey's fibres and periodontal scar tissue showed a slight increase in the mucosa excision group and the periosteal graft group compared with the control group. In the mucosa-periosteum excision group, the density increased significantly as expected.ConclusionsAll of these findings testify that retaining the periosteum or replacement with a periosteum graft after surgery can prevent the inhibition of maxillary growth. 相似文献
10.
Irene Esposito Bj?rn Konukiewitz Anna Melissa Schlitter Günter Kl?ppel 《World journal of gastroenterology : WJG》2014,20(38):13833-13841
Despite major improvements concerning its diagnosis and treatment, pancreatic ductal adenocarcinoma (PDAC) remains an aggressive disease with an extremely poor prognosis. Pathology, as interface discipline between basic and clinical medicine, has substantially contributed to the recent developments and has laid the basis for further progress. The definition and classification of precursor lesions of PDAC and their molecular characterization is a fundamental step for the potential identification of biomarkers and the development of imaging methods for early detection. In addition, by integrating findings in humans with the knowledge acquired through the investigation of transgenic mouse models for PDAC, a new model for pancreatic carcinogenesis has been proposed and partially validated in individuals with genetic predisposition for PDAC. The introduction and validation of a standardized system for pathology reporting based on the axial slicing technique has shown that most pancreatic cancer resections are R1 resections and that this is due to inherent anatomical and biological properties of PDAC. This standardized assessment of prognostic relevant parameters represents the basis for the successful conduction of multicentric studies and for the interpretation of their results. Finally, recent studies have shown that distinct molecular subtypes of PDAC exist and are associated with different prognosis and therapy response. The prospective validation of these results and the integration of molecular analyses in a comprehensive pathology report in the context of individualised cancer therapy represent a major challenge for the future. 相似文献