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《Journal of anatomy》2017,231(2):260-274
The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10 weeks of development. Human embryos (5–10 weeks of development) were visualized using Amira 3D® reconstruction and Cinema 4D® remodelling software. Vertebral bodies were identifiable as loose mesenchymal structures between the dense mesenchymal intervertebral discs up to 6 weeks and then differentiated into cartilaginous structures in the 7th week. In this week, the dense mesenchymal neural processes also differentiated into cartilaginous structures. Transverse processes became identifiable at 6 weeks. The growth rate of all vertebral bodies was exponential and similar between 6 and 10 weeks, whereas the intervertebral discs hardly increased in size between 6 and 8 weeks and then followed vertebral growth between 8 and 10 weeks. The neural processes extended dorsolaterally (6th week), dorsally (7th week) and finally dorsomedially (8th and 9th weeks) to fuse at the midthoracic level at 9 weeks. From there, fusion extended cranially and caudally in the 10th week. Closure of the foramen magnum required the development of the supraoccipital bone as a craniomedial extension of the exoccipitals (neural processes of occipital vertebra 4), whereas a growth burst of sacral vertebra 1 delayed closure until 15 weeks. Both the cranial‐ and caudal‐most vertebral bodies fused to form the basioccipital (occipital vertebrae 1–4) and sacrum (sacral vertebrae 1–5). In the sacrum, fusion of its so‐called alar processes preceded that of the bodies by at least 6 weeks. In conclusion, the highly ordered and substantial changes in shape of the vertebral bodies leading to the formation of the vertebral canal make the development of the spine an excellent, continuous staging system for the (human) embryo between 6 and 10 weeks of development.  相似文献   
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Background

To compare the predictive effect of the Masaoka-Koga staging system and the International Association for the Study of Lung Cancer (IASLC)/the International Thymic Malignancies Interest Group (ITMIG) proposal for the new TNM staging on prognosis of thymic malignancies using the Chinese Alliance for Research in Thymomas (ChART) retrospective database.

Methods

From 1992 to 2012, 2,370 patients in ChART database were retrospectively reviewed. Of these, 1,198 patients with complete information on TNM stage, Masaoka-Koga stage, and survival were used for analysis. Cumulative incidence of recurrence (CIR) was assessed in R0 patients. Overall survival (OS) was evaluated both in an R0 resected cohort, as well as in all patients (any R status). CIR and OS were first analyzed according to the Masaoka-Koga staging system. Then, they were compared using the new TNM staging proposal.

Results

Based on Masaoka-Koga staging system, significant difference was detected in CIR among all stages. However, no survival difference was revealed between stage I and II, or between stage II and III. Stage IV carried the highest risk of recurrence and worst survival. According to the new TNM staging proposal, CIR in T1a was significantly lower comparing to all other T categories (P<0.05) and there is a significant difference in OS between T1a and T1b (P=0.004). T4 had the worst OS comparing to all other T categories. CIR and OS were significantly worse in N (+) than in N0 patients. Significant difference in CIR and OS was detected between M0 and M1b, but not between M0 and M1a. OS was almost always statistically different when comparison was made between stages I–IIIa and stages IIIb–IVb. However, no statistical difference could be detected among stages IIIb to IVb.

Conclusions

Compared with Masaoka-Koga staging, the IASLC/ITMIG TNM staging proposal not only describes the extent of tumor invasion but also provides information on lymphatic involvement and tumor dissemination. Further study using prospectively recorded information on the proposed TNM categories would be helpful to better grouping thymic tumors for predicting prognosis and guiding clinical management.  相似文献   
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目的:研究MRI在T3、T4期直肠癌术前新辅助治疗疗效评估中的应用价值。方法:选择本院2013年1月-2015年1月收治的40例经病理证实为T3、T4期直肠癌患者为研究对象,回顾性分析其术前新辅助治疗前后的MRI资料。结果:术前新辅助治疗前肿瘤≤5 cm的患者为13例,5 cm的患者为27例;40例患者的DWI均表现为高信号,而ADC均表现为降低;16例处于T3期,24例处于T4期。经过治疗后肿瘤1.0 cm有9例,1.0~3.0 cm有11例,3.0~5.0 cm有15例,≥5.0 cm有5例;40例患者均表现为DWI的低信号,ADC信号升高。T1期4例,T2期22例,T3期10例,T4期4例。术后的病理分期为:T1期5例,T2期21例,T3期10例,T4a期1例,T4b期3例。结论:MRI可以对直肠癌T3、T4期患者术前新辅助治疗前后肿瘤大小和分期给出良好的判定。  相似文献   
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目的探讨根治性前列腺癌病理分期及p T2病理亚分期的意义。方法回顾性分析根治性前列腺癌30例,观察肿瘤累及范围、前列腺外及精囊腺侵犯情况,依据2002/2010年TNM分期系统对其行病理分期。结果 30例术前临床评估为局限性前列腺癌,前列腺癌根治术后病理分期:p T2期15例,p T3a期10例,p T3b期5例。p T2期肿瘤中2例为p T2a,13例为p T2c,占p T2期肿瘤的86.7%,无p T2b期肿瘤。结论根治性前列腺癌术后病理分期更加直观和准确,更能够反映肿瘤真实的状态,对预后的评估更有价值,而2002/2010年TNM分期系统对于p T2期肿瘤的亚分期,仅依据肿瘤累及腺叶的范围划分并不完善,需进一步加以改善。  相似文献   
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Purpose: To further evaluate fluorine 18 fluoro-deoxyglucose positron emission tomography (FDG PET) in the staging of ocular adnexal lymphoproliferative disease (OALD).

Methods: Retrospective and prospective case series with review of clinical and imaging records including computed tomography (CT), FDG PET (±PET/CT) and/or magnetic resonance imaging (MRI).

Results: Thirty-four patients had FDG PET and CT scans at initial staging. Eleven were retrospectively reviewed and 23 were prospectively enrolled. Of 34 patients, 17 (50%) had primary disease, 17 (50%) had secondary and of these, 13 patients (38%) had OALD as their initial manifestation. Sixteen patients had active systemic disease in conjunction with their orbital disease. Systemic disease was demonstrated by FDG PET (± CT) in 15 of 16 (94%) patients and 11 of 16 (69%) patients with CT. FDG PET found orbital disease in 27 of 34 patients (79%) versus 33 of 34 patients with orbital CT (97%). Four of 16 patients in which FDG-PET detected systemic disease where CT did not were upstaged and their management changed significantly in 5 cases.

Conclusions: This study reaffirms FDG PET as an important part of initial staging. Our study suggests FDG PET detects systemic disease more reliably than CT alone and results in significant changes in management. Our findings suggest FDG PET detection for local OALD is less sensitive than CT. MRI is helpful in augmenting other imaging modalities in further identifying disease. Given the prevalence of simultaneous systemic presentations of OALD, FDG PET in this regard is especially important and highlights the need for coordinated multidisciplinary care.  相似文献   

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