Real-time automatic extraction of lumen region and boundary from endoscopic images

A new approach to the automatic extraction of the lumen region and its boundary for gastrointestinal (GI) endoscopic images is presented. First, a quasi region of interest, the darker regions of the image, is segmented using a region splitting scheme termed progressive thresholding. The centre of mass of this segmented region acts as a seed for further processing. Then the lumen region is obtained using a region growing technique called the integrated neighbourhood search (INS). A new quad structure based technique is introduced to enhance the INS speed significantly. A back projection algorithm is suggested to optimise the search for pixels belonging to the lumen region and boundary. A boundary-thinning algorithm is also proposed to remove the redundant pixels from the lumen boundary and to generate a connected single pixel width boundary. The proposed approach does not need a priori knowledge about the image characteristics. The experimental results indicate that the proposed technique enhances the speed of conventional INS by 45.5% to 28.6% based on the lumen size varying from 22,709 pixels to 4947 pixels. The main advantage of the proposed technique is its high-speed response that facilitates real-time analysis of endoscopic images.     

大鼠终纹床核向结合臂旁核的投射 Ⅲ.神经降压肽、促肾上腺皮质激素释放因子肽能通路研究

用荧光金逆行束路追踪结合免疫荧光双标记技术及HRP逆行束路追踪结合免疫细胞化学双标记技术证明,在大鼠终纹床核投射至结合臂旁核的神经元中,位于前外侧区卵圆核及其腹侧邻近区中的部分为神经降压肽及促肾上腺皮质激素释放因子免疫反应阳性,双标记细胞分别约占这个部位逆行标记细胞总数的40％及20％;在前腹侧区的梭形核及大细胞核中,部分为促肾上腺皮质激素释放因子免疫反应阳性。     

Postsynaptic fibers reaching the dorsal column nuclei in the rat

Postsynaptic fibers reaching the dorsal column nuclei were investigated in rat by means of retrograde transport of wheat germ agglutinin-horseradish peroxidase conjugate. Each nucleus received only ipsilateral afferents with most of the labeled cells forming a band which covered the mediolateral extent of the dorsal horn in an area that resembled lamina IV in the cat. The labeling excluded the reticular extension of the neck of the dorsal horn. Lumbosacral afferents were restricted to the gracilis nucleus and cervicothoracic afferents to the cuneatus nucleus. Cervical and anterior lumbar levels showed additional projections coming from their most medial parts. The organization of this second-order pathway in rat is similar to that in cat and monkey.     

Retrograde migration of glove powder in the human female genital tract

BACKGROUND: This study in humans was undertaken to evaluate earlier results from animal research showing a retrograde migration of glove powder from the vagina into the intra-abdominal cavity. METHODS: One study group was gynaecologically examined with powdered gloves the day before an abdominal hysterectomy and another group 4 days pre-operatively. There were two control groups similarly examined with powder-free gloves. Cell smears were taken from the peritoneal fluid and during the operation further smears were taken from the Fallopian tubes, uterine cavity and cervical canal. RESULTS: Statistically significant differences were found for large starch particles at all locations between the study and control groups examined 1 day pre-operatively. Considering small starch particles, there were significant differences in cervix (P < 0.001), uterus (P < 0.01) and the Fallopian tubes (P < 0.01). The combined results also show significant differences between both large and small starch particles in cervix, uterus and the Fallopian tubes. There were also differences between the study and control groups examined 4 days pre-operatively, but these were not statistically significant except for small and large starch particles in uterus (P < 0.01, P < 0.05) and cervix (P < 0.05, P < 0.05). CONCLUSIONS: This study has pointed out a retrograde migration of starch also in humans after a gynaecological examination with powdered gloves. Consequently, powder or any other potentially harmful substance that can migrate from the vagina should be avoided.     

肝外胆管梗阻病变MSCT曲面重建胆管成像与MRCP的比较研究

目的比较多层螺旋CT（MSCT）曲面重建（CPR）胆管成像与磁共振胰胆管成像（MRCP）对肝外胆管梗阻病变的诊断价值。方法66例经B超检查提示有肝外胆管梗阻病变的患者，采用单次激发快速自旋回波（SSFSE）序列，行MRCP检查，同期采用10mm层厚层距，使用血管对比剂，行MSCT增强扫描，将门静脉期图像采用2．5mm层厚、1．25mm层距重建，获得轴面源像（ASI），数据传输至图像工作站，作CPR胆管成像。比较CPR胆管成像、MRCP对肝外胆管梗阻病变的定位、定性诊断价值。结果CPR胆管成像、MRCP成功率为100％；CPR胆管成像、MRCP均对肝外胆管梗阻部位做出明确诊断，定位诊断率为100％；CPR胆管成像、MRCP定性诊断率分别为95．5％和80．9％。结论CPR胆管成像、MRCP对肝外胆管梗阻病变均能明确定位，CPR胆管成像定性诊断率明显高于MRCP，CPR胆管成像显示胆管及其周围病变与扩张胆管的关系更直观。     

依赖性膜磷脂结合蛋白AnnexinⅡ对大鼠脊髓横断损伤的修复作用

目的在体内实验中观察钙依赖性膜磷脂结合蛋白AnnexinⅡ对大鼠脊髓损伤以及神经干细胞移植的作用。方法在成年大鼠全横断脊髓损伤的局部微量注射AnnexinⅡ，观察其对损伤的脊髓神经细胞存活、神经纤维生长和损伤后的功能恢复的影响，以及对联合移植的胚胎神经干细胞移植后存活和迁移的影响。结果在动物脊髓横断损伤6周，神经干细胞移植4周后，损伤局部微量注射AnnexinⅡ＋NSC移植组实验动物的运动评分结果较空白对照组和单独进行NSC移植组都有明显增高（JP〈0．01），脊髓损伤处的空洞面积也较上述两组显著减小（P〈0．01）；注射AnnexinⅡ＋NSC组损伤节段以上荧光金标记神经细胞数目较空白对照组明显增多（P〈0．01）。结论AnnexinⅡ蛋白可能具有减小局部损伤空洞面积，保护损伤的神经元和神经纤维并防止其走向变性和死亡的效应，并对神经干细胞的移植效应有一定的促进和协同作用，使脊髓损伤大鼠的功能得到一定程度的恢复。     

Fluorescent retrograde triple labeling of brainstem reticular neurons

The present study was aimed at the anatomical identification in the rat of neurons of the lower brainstem reticular formation which give off axonal branches ascending bilaterally to more rostral structures and descending unilaterally to the spinal cord. Three fluorescent tracers were injected in one and the same animal. Fast Blue was injected in the midbrain tegmentum, in the termination areas and fiber bundles of the ascending reticular efferents; Evans blue was injected in the midbrain tegmentum on the other side; either Nuclear Yellow or Diamidino Yellow was injected in the white and gray matter of the upper cervical cord. All three populations of single-labeled cells, as well as double labeled either from the midbrain injections or from the ipsilateral injections in the mesencephalon and spinal cord, were intermingled in the medial reticular formation. Very few cells double labeled from the contralateral mesencephalon and ipsilateral spinal cord were also seen. However, the main finding of the present study was the visualization of triple-labeled cells. The latter were mainly located ipsilaterally to the injections in the spinal cord. The present results indicate that reticular cells give off divergent multiple branches descending to the ipsilateral spinal cord and ascending bilaterally to rostral centers.     

逆行带锁髓内钉治疗股骨远端骨折的应用解剖

目的:为带锁髓内钉治疗股骨远端骨折提供形态学基础。方法:①选用30例成人干燥股骨测量股骨内外侧髁、内外上髁、髁间窝有关数据进行统计分析。②20侧下肢标本解剖观测膝降动脉及隐神经髌下支的分支、分支等及两者的关系。结果:髁间窝呈U型占35%,V型占65%,此窝最宽处横径:左侧(1.98±0.36)cm, 右侧(2.06±0.29) cm;内侧髁后关节面宽,左侧(2.21±0.23) cm,右侧(2.34±0.29) cm;内、外上髁的距离,左侧(7.30±0.60)cm,右侧(7.43±0.57)cm。膝降动脉髌下支和隐神经髌下支呈紧密的伴行关系。隐神经在缝匠肌中下1/3交界点穿出,有上、下两支分布到膝关节前外侧皮肤。结论:术中注意这些解剖位置特点,避免损伤神经和血管,减少手术出血,防止并发症。     

Ionic requirements for in vitro retrograde axonal transport of acetylcholinesterase

The ionic requirements for retrograde axonal transport of acetylcholinesterase were studied in vitro in desheathed spinal nerves of the bullfrog; the accumulation of enzyme activity distal to a ligature served to evaluate the status of retrograde transport. After an 18 h incubation in control medium, the 2 mm segment of nerve immediately distal to the ligature contained approximately twice as much acetylcholinesterase activity as other more distal segment. Accumulation of acetylcholinesterase distal to the ligature was reduced during incubation in Ca2+-free medium plus 1 mM EGTA; retrograde transport was not diminished by the substitution of sucrose for the NaCl of the medium. In comparison with ionic requirements for orthograde fast axonal transport of protein, retrograde transport of acetylcholinesterase thus appears to share a Ca2+ requirement, but not a requirement for NaCl.     

Dysphagia lusoria: proposal of a new treatment

Summary Recent observation of one patient suffering from dysphagia lusoria has suggested critical review of treatment of the symptomatic aberrant right subclavian artery. Surgical correction of such an anomaly is difficult and may produce serious complications, and is not always successful. Endoscopic dilatation of the oesophageal stricture, even though it might only produce temporary relief of dysphagia, represents a valid therapeutical alternative because of its favourable cost/benefit ratio, low incidence of complications and patient acceptability.