A Bayesian approach to subvoxel tissue classification in NMR microscopic images of trabecular bone

NMR microscopy is currently being used as an investigational tool for the evaluation of micromorphometric parameters of trabecular bone as a possible means to assess its strength. Since, typically, the image voxel size is not significantly smaller than individual trabecular elements, partial volume blurring can be a major complication for accurate tissue classification. In this paper, a Bayesian segmentation technique is reported that achieves improved subvoxel tissue classification. Each voxel is subdivided either into eight subvoxels twice the original resolution, or up to four subvoxels along the transaxial direction and the subvoxels optimally classified as either bone or marrow. Based on a statistical model for partial volume blurring, the likelihood for the number of marrow subvoxels in each voxel can be computed on the basis of its measured signal. To resolve the ambiguity of the location of the marrow subvoxels, a Gibbs distribution is introduced to model the interaction between the subvoxels. Neighboring subvoxel pairs with the same tissue label are encouraged, and pairs with distinct labels are penalized. The segmentation is achieved by maximizing the a posteriori probability of the label image using the block ICM (iterative conditional mode) algorithm. The potential of the proposed technique is demonstrated in real and synthetic NMR microscopic images.     

应用单克隆抗体(MoAb)对白血病免疫分型的临床研究

报告了应用单克隆抗体对25例淋巴细胞白血病、5例慢性粒细胞白血病及15例急性非淋巴细胞白血病进行免疫分型并与AB分型作比较,结果提示免疫分型可以弥补FAB分型的不足,它有助于白血病临床诊断、鉴别诊断、指导治疗和判断预后。     

Colonoscopic classification of internal hemorrhoids: Usefulness in endoscopic band ligation

Background:  Bleeding is one of the main symptoms of internal hemorrhoids. However, the conventional Goligher's classification of internal hemorrhoids does not consider the severity of bleeding. We intended to establish a useful method for evaluating internal hemorrhoids using a colonoscope that reflected the severity of the symptoms.
Methods:  Using a colonoscope in the retroflexed and forward viewing position, 104 patients with symptomatic internal hemorrhoids were evaluated based on the criteria of range, form and red color signs (RCS). Range was determined by the circumferential distribution of internal hemorrhoids and scaled from 0 to 4. Form was determined by size and scaled from 0 to 2. The presence of RCS was also evaluated. Symptoms were determined by interview and scaled from 0 to 3. Patients were treated by endoscopic band ligation (EBL) and were examined endoscopically before and 4 weeks after the treatment.
Results:  Before the treatment, range, form and RCS were significantly correlated to bleeding ( P <  0.01), and form was significantly correlated to prolapse ( P <  0.05). The endoscopic classification scores at 4 weeks after EBL improved significantly (range from 3.25 ± 0.05–0.56 ± 0.08 [ P <  0.01] and form from 2.81 ± 0.04–0.56 ± 0.07 P <  0.01).
Conclusion:  The new endoscopic classification of internal hemorrhoids proved to be closely correlated to symptoms, particularly bleeding, and thus highly useful in evaluating the effectiveness of the treatment.     

椎动脉形态学异常对后循环短暂性脑缺血发作症状持续时间的影响

目的 探讨椎动脉形态学异常对后循环TIA症状持续时间的影响。
方法 回顾性分析2015年10月-2018年3月在中国科学院大学重庆仁济医院神经内科完成头颈部DSA
或CTA的后循环TIA住院患者临床资料，根据症状持续时间分为<10 min组、10～59 min组和≥60 mi n组，
比较椎动脉形态异常各亚型在3组间的差异。通过多因素Logistic回归分析明确椎动脉形态异常与后
循环TIA症状持续时间之间的关系。
结果 共纳入237例患者，其中症状持续时间<10 min组109例（45.99%）、10～59 min组71例（29.96%）
和≥60 min组57例（24.05%）。一般临床资料的比较显示，性别、椎动脉和基底动脉狭窄率≥50%
在3组间差异具有统计学意义（P＜0.05）。椎动脉形态异常中，动脉粥样硬化性椎动脉狭窄（狭窄
率1%～99%）在3组间的差异具有统计学意义（P =0.004），而一侧迂曲、双侧迂曲、一侧优势、一
侧优势合并迂曲和起源异常在3组间差异均无统计学意义；多因素Logi sti c回归分析显示椎动脉
狭窄（OR 2.500，95%CI 1.381～4.525，P =0.002）、基底动脉狭窄率≥50%（OR 12.066，95%CI
1.446～100.668，P =0.021）是TI A症状持续时间延长的独立影响因素。
结论 椎动脉狭窄和基底动脉狭窄率≥50%是影响后循环TIA症状持续时间延长的独立影响因素。     

胸椎黄韧带骨化症的CT分型及手术方式选择

目的:探讨胸椎黄韧带骨化症的CT分型及手术治疗方法.方法:1997年1月至2006年12月手术治疗胸椎黄韧带骨化症患者48例102个节段,根据CT表现分为3型,单侧型18个节段,双侧型45个节段,两侧融合型39个节段.单侧型将椎板、关节突内侧和未骨化处磨薄,再把骨化物对侧和头尾侧充分减压使其孤立,用枪状咬钳将关节突内侧磨薄处咬开使其游离,齿镊夹住骨块轻提起由中间向外侧剥离摘除骨块;双侧型将椎板、关节突内侧和未骨化处磨薄,先将骨化物头尾侧充分减压,将中间未骨化黄韧带咬除分隔,使两侧骨化物孤立,再按单侧型手术方法逐块处理;两侧融合型将椎板、关节突内侧和未骨化处磨薄,先将骨化物头尾侧充分减压,从对侧关节突内侧磨薄处咬开使骨化物孤立,再将术侧关节突内侧磨薄处咬开使骨化物游离,齿镊夹住骨块轻提起由对侧向术者侧剥离摘除骨块.术前术后采用改良JOA下肢运动功能评分评价运动功能.结果:全部患者顺利完成手术.手术时间平均2.8h,出血量平均290ml.术后无症状加重病例,1例出现脑脊液漏,经保守治疗后痊愈.40例患者随访5～62个月,平均28个月,JOA下肢运动功能评分术前1.8±1.1分,末次随访时为3.7±0.6分,与术前比较差异有显著性(P<0.01).疗效按JOA评分改善率优32例,良6例,可2例,优良率为95%.结论:对胸椎黄韧带骨化症患者根据CT分型采取不同的手术方式可取得满意的治疗效果.     

内镜活检对胃癌组织学分类术前诊断的价值

目的 探讨内镜活检对胃癌组织学分类术前诊断的价值。方法 术前对141例胃癌患的内镜活检标本分别根据Lauren分类和世界卫生组织（WHO）分类判断组织学分类，并与手术标本结果对照。结果 内镜活检对胃癌Lauren分类术前诊断的准确率为76.6%。对肠型胃癌诊断的敏感性和特异性分别为85.4%和80.6%。而对弥漫型胃癌则分别为82.7%和80.3%，在59例术前诊断为肠型胃癌的病例中，18例（30.5%)在手术标本中呈弥漫性行生长，而在75例术前诊断为弥漫型胃癌的病例中，仅6例（8.0%)术后诊断为肠型胃癌，内镜活检对胃癌WHO分类术前诊断的准确率为87.2%，其中对乳头状/管状腺癌，黏液腺癌和印戒细胞癌的敏感性分别为91.9%。33.3%和66.7%。结论 内镜活检对胃癌组织学分类的术前诊断具有较高的临床应用价值。     

The Hyperplantarflexion Ankle Fracture Variant

Various patterns of ankle fractures that are not accounted for by common classification systems have been the subject of case reports. The first difficulty with these variant patterns is recognizing all associated pathology, followed by the successful application of stable fixation. The purpose of this study was to describe the common morphologic features and ligamentous injuries of a unique variant fracture pattern, as well as the surgical treatment technique and the short-term functional and radiographic outcomes. Of 121 consecutive unstable ankle fractures over a 2-year period, 7 patients were found to have a similar constellation of injuries around the ankle. A vertical shear fracture of the posteromedial tibial rim was the main feature. Six of the 7 also had a fracture of the posterior malleolus. On magnetic resonance imaging, the deltoid and posterior tibiofibular ligaments were intact in all cases. Fractures were treated with open anatomic reduction of the posteromedial and posterior fragments with antiglide plate fixation. All fractures healed at 2 months without loss of reduction, fixation failure, or surgical complications. The average American Academy of Orthopaedic Surgeons lower extremity score was 79 at an average of 8 months' follow-up. The common radiographic and morphologic features associated with this posteromedial fracture indicate that it likely occurs through a common mechanism that involves hyperplantarflexion. The characteristics of this fracture pattern have not been fully described previously, but this ankle fracture variant may occur in up to 6% of cases. Unstable ankle fractures should be evaluated carefully for evidence of posteromedial involvement so appropriate treatment may proceed.     

Neural classifier construction using regularization, pruning and test error estimation

In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems.     

云南省卫生资源配置标准的弹性系数研究

目的　在进行云南省区域分类基础上制定云南省区域卫生资源配置标准标志值后 ,根据云南省各个地区的特点增加不同弹性系数。方法　采用流行病学研究方法 ,收集和分析云南省不同地州市 1990～ 1999年有关人口、社会经济状况及卫生经费的投入、居民健康状况、居民文化、生活水平、少数民族状况、旅游地区、边境线长短及贫困状况等资料。结果　研究结果表明曲靖地区、玉溪市、保山地区增加弹性系数最少 ,分别为 0 67%、 1 5 8%和1 68% ,怒江州、迪庆州和西双版纳州增加弹性系数最多 ,分别为 11 15 %、 10 2 5 %和 9 84 %。其它地区的弹性系数分别为昆明市 5 88% ,昭通地区 2 3 1% ,楚雄州 2 3 0 % ,红河州 7 0 3 % ,文山州 5 5 3 % ,思茅地区 7 4 3 % ,大理州4 94 % ,德宏州 6 78% ,丽江地区 4 3 5 % ,临沧地区 6 13 %。结论　云南省区域卫生配置标准的弹性系数研究为云南省卫生资源区域分类配置标准提供了科学依据 ,不同弹性系数体现了云南省不同地区的卫生资源区域分类配置标准的公平性、合理性及实用性     

血液白细胞图象的计算机自动分割方法研究

本文提出了一套血液白细胞图象的计算机自动分割方法。实际测试表明：该方法稳定可靠且有效。单个白细胞检出成功率达９６％，区域分割吻合率平均达９４％，现已将该方法装入作者研制的白细胞自动分类识别ＬＥＵＫ分析系统的分割模块中。