防酸隔爆式消氢装置的研究

本文根据劳动卫生和环境保护的要求,对电力、邮电、化工等部门用作备用电源的铅蓄电池采取防酸、隔爆、消氢措施,并研制成实用装置,效果较好。文中叙述了该装置的工作原理及主要试验结果。     

Spatial distribution of evoked potentials in the inferior olivary nucleus by stimulation of the visual afferents in the rat

Visual pathways (optic disc, optic nerve and pretectal regions) were electrically stimulated and evoked potentials were explored throughout the inferior olive in the anesthetized rat. Responsive areas were identified as the caudal half of the dorsal cap, nucleus beta and the most caudal region of subnucleus c of the medial accessory olive. No field potentials were identified in the rostral half of the dorsal cap, its ventrolateral outgrowth or the dorsomedial cell column. Contralateral retinal afferents were only effective all over the responsive areas.     

透明帽辅助内镜下食管异物治疗术的疗效分析

目的比较透明帽辅助内镜下食管异物取出术及传统内镜下异物取出术的疗效差异。方法选取96例食管异物嵌顿患者随机分成两组,分别施行透明帽辅助内镜下异物取出术(简称透明帽组)或传统内镜下异物取出术(简称传统组),收集两组患者各项临床资料,同时记录其接受内镜下治疗的成功情况、内镜下操作时间、内镜下视野清晰度以及并发症发生情况等数据并进行统计分析。结果接受透明帽辅助内镜下异物取出术的48例患者,均成功完成异物取出治疗,另外48例接受传统内镜下异物取出患者中有46例成功,另外2例转为透明帽辅助下异物取出后成功(成功率95.83%),两组的成功率比较差异无统计学意义(P0.05);透明帽组的平均内镜下操作时间为(8.29±2.83)min,传统组的平均内镜下操作时间为(10.69±3.19)min,两组比较差异无统计学意义(P0.05);内镜下视野清晰度方面,透明帽组视野清晰度A级45例,B级3例,传统组视野清晰度A级35例,B级11例,C级2例,两组间比较差异有统计学意义(P=0.020);所有96例患者均未出现严重出血、穿孔及死亡等并发症。结论透明帽辅助内镜下食管异物取出术是一种安全有效的内镜下异物治疗方案,其可提供更好的内镜下操作视野,有利于提高手术成功率,值得进一步推广应用。     

透明帽法内镜黏膜切除术与多环黏膜套扎切除术治疗早期食管癌及癌前病变的比较研究

目的比较透明帽法内镜下黏膜切除术（EMR—Cap）与多环黏膜套扎切除术（MBM）治疗早期食管癌及癌前病变的疗效和安全性。方法回顾性分析2008年12月至2009年12月间在中国医学科学院肿瘤医院内镜科接受EMR—CaP治疗的30例（EMR—Cap组）及2010年1月至2011年1月间接受MBM治疗的32例（MBM组）早期食管癌及癌前病变患者的临床资料,比较两种技术的疗效、安全性及费用。结果EMR,Cap组平均病变切除时间和治疗总时间分别为26rain和43min．明显长于MBM组的10min和32min（P=0．036,P=0．038）。切除病变总厚度和黏膜下切除深度两组差异无统计学意义（均P〉0．05）。EMR—Cap组平均治疗费用为（5466±354）元,明显高于MBM组的（4014±368）元（P=0．008）。EMR—Cap组出现术后狭窄1例,MBM组出现术中穿孔1例。术后随访17～42个月,无一例局部复发,EMR—Cap组m现1例淋巴结转移。结论EMR—Cap和MBM均是治疗早期食管癌和癌前病变微创、安全和有效的手段。在保证相同治疗效果的前提下,与EMR—Cap相比,MBM具有操作简单、治疗时间短、治疗成本低的优点,适宜广泛推广和开展。     

Association between abdominal fat distribution and coronary plaque instability in patients with acute coronary syndrome

Background and aimsThis study aimed to assess possible association of detailed abdominal fat profiles with coronary plaque characteristics in patients with acute coronary syndrome (ACS).Methods and resultsIn 60 patients with ACS, culprit arteries were evaluated at 1-mm intervals (length analyzed: 66 ± 28 mm) by grayscale and integrated backscatter intravascular ultrasound (IB-IVUS) before percutaneous coronary intervention. Standard IVUS indexes (as a volume index: volume/length), plaque components (as percent tissue volume) and fibrous cap thickness (FCT) were assessed by IB-IVUS. Plain abdominal computed tomography was performed to evaluate subcutaneous adipose tissue (SAT) area, visceral adipose tissue (VAT) area, and VAT/SAT ratio. While SAT area only correlated with vessel volume (r = 0.27, p = 0.04), VAT area correlated positively with vessel (r = 0.30, p = 0.02) and plaque (r = 0.33, p = 0.01) volumes and negatively with FCT (r = −0.26, p = 0.049), but not with percent plaque volume and plaque tissue components. In contrast, higher VAT/SAT ratio significantly correlated with higher percent lipid (r = 0.34, p = 0.008) and lower percent fibrous (r = −0.34, p = 0.007) volumes with a trend toward larger percent plaque volume (r = 0.19, p = 0.15), as well as thinner FCT (r = −0.53, p < 0.0001). In the multiple regression analysis, higher VAT/SAT ratio was independently associated with higher percent lipid with lower percent fibrous volumes (p = 0.03 for both) and thinner fibrous cap thickness (p = 0.0001).ConclusionCoronary plaque vulnerability, defined as increased lipid content with thinner fibrous cap thickness, appears to be more related to abnormal abdominal fat distribution, or so-called hidden obesity, compared with visceral or subcutaneous fat amount alone in patients with ACS.     

Acid diffusion through rat duodenal mucosal cap

Acid induced duodenal injury occurs immediately following exposure to strong acid but does not worsen despite continuous perfusion with the acid. A thick gelatinous cap is found overlying the duodenum when examined histologically. The purpose of this study was to quantitate the resistance to acid diffusion by native duodenal mucus and the cap material. Rat duodenum was perfused with acid. The mucus from control and acid-perfused animals was harvested and the diffusion coefficient measured. Mucus from the duodenums of anesthetized rats was mixed with bromphenol blue and placed into capillary tubes. The tubes were submersed in 0.15 N HCl at 37°C. The color change from blue to yellow was measured with time as the HCl migrated through the tube. From the distance and time data, the diffusion coefficient could be calculated. Controls of bromphenol blue in water were studied. The diffusion coefficient for HCl in water was 30.1 ± 0.9 × 10^–6 cm²/sec, nearly identical to the standard value reported in the literature. For the duodenal mucus adherent to the epithelial surface, it was 1.1 ± 0.1 × 10^–6 cm²/sec. Following perfusion with 0.15 N HCl, a 279.6 ± 44-m-thick mucus cap formed over the duodenum that had a diffusion coefficient of 1.8 ± .3 × 10^–8 cm²/sec. In response to injury, the duodenum protects against continued damage by producing a mucoid cap that it highly resistant to acid diffusion.     

基牙不同牙周状况下球帽附着体义齿支持组织的应力分析

目的探讨基牙牙周组织不同程度吸收对球帽附着体义齿支持组织VonMises等效应力的影响。方法分别建立基牙牙周组织正常、吸收1／4、吸收1／3、吸收1／2的球帽附着体义齿模型,采用垂直向加载力300N,分析支持组织的VonMises等效应力变化。结果随着基牙牙周组织的吸收基牙应力集中区逐渐扩大,以根尖区扩大较明显,第二前磨牙颈部出现高应力区,最大VonMises等效应力分别为25．6962MPa、27．2047MPa、34．4062MPa、47．3841MPa;牙周膜根尖应力集中区也逐渐扩大;而缺牙区牙槽嵴的应力变化较小。结论基牙牙周组织吸收小于1／3时,支持组织应力逐渐增加,采取相应的措施减小验力,仍可使用球帽附着体义齿修复。吸收1／2时支持组织高应力区应力变化显著,对于此情况不建议采用球帽附着体义齿修复。     

Small neurons in the vestibular nerve root project to the marginal shell of the anteroventral cochlear nucleus in the cat

We injected biotinylated dextran amine (BDA) into marginal shell regions of the anteroventral cochlear nucleus (AVCN) of the cat. These injections led to retrograde labeling of cells including small cells (median soma area = 111 μm², equivalent diameter = 11.9 μm) in the vestibular nerve root (VNR), just ventral to an anterior part of the AVCN. This is an unexpected new finding. The cells were scattered among BDA-labeled fibers and were oriented parallel to the course of the VNR fibers. We suggest that the small neurons of the VNR might serve as second-order vestibular neurons conveying information from vestibular end organs to the cochlear nucleus (CN) and/or act as interneurons between the olivocochlear fibers in the VNR and the CN.