创伤性尿道狭窄术后吻合口形态超声诊断与手术结果的对照

目的 评价创伤性尿道狭窄术后吻合口形态超声诊断的可靠性。方法 对68例创伤性尿道狭窄术后排尿困难者尿道吻合口形态进行超声观察,并与再次手术结果对照。结果 尿道吻合口形态表现共4种,即狭窄疤痕形成（43例）、假道（12例）、尿道活瓣（4例）和狭窄合并关闭不全（9例）。超声形态表现类型和定位诊断均经手术证实。超声对手术吻合口狭窄疤痕长度和深度估测的相关系数γ分别为0．97,0．86,P＜0．01。结论 尿道超声成像是评价尿道狭窄术后吻合口形态可靠的诊断方法,有助于指导术后排尿困难病例的临床正确处理。     

体外培养的新生大鼠成骨细胞形态及功能的时相性变化

目的：探索大鼠成骨细胞（OB）在体外不同时间的形态及功能变化。方法：在为期28天的细胞培养中动态观察了新生大鼠头盖骨OB的活细胞形态变化,并与其皮肤成纤维细胞（FB）的形态变化作了比较,测定了OB中I型原胶原羧基端前肽（PICP）,骨钙素（BGP）和碱性磷酸酶（ALP）的表达量变化。结果：OB与FB在早期散在分布时形态相似,汇合以后两者逐渐出现差异,OB在28天才可用Von Kossa法染到明显钙盐沉着;PICP,BGP分别于初始植入后第7,19天有表达高峰,ALP在12－16天和≥28天有两个表达高峰。结论：体外培养的大鼠OB形态及功能呈动态变化并具有高度趋同性。     

Morphology and spatial arrangement of large retinal ganglion cells projecting to the optic tectum in the perciform fish Pholidapus dybowskii

Using retrograde HRP labeling from the optic nerve (ON) or optic tectum (OT), we have visualized large ganglion cells (LGCs) in wholemounted retinas of the teleost Pholidapus dybowskii and studied their morphology and spatial properties. In all, three LGC types were distinguished. In a previous paper, detailed data were provided on one type, biplexiform cells [Pushchin, I. I., & Kondrashev, S. L. (2003). Biplexiform ganglion cells in the retina of the perciform fish Pholidapus dybowskii revealed by HRP labeling from the optic nerve and optic tectum. Vision Research, 43, 1117-1133]. Here, we present data on the other two confirmed types, alpha(a) and alpha(ab) cells. The types differed in the level of dendrite stratification, dendrite arborization pattern, dendritic field size, and other features, and formed in the retina significantly non-random, spatially independent mosaics. Both types were labeled from the OT, indicating their participation in OT-mediated visual reactions. The comparison of spatial properties of alpha(a) and alpha(ab) mosaics labeled from the ON and OT suggests that the OT is the major or one of the major projection areas of both types. We also describe the morphology of cells resembling alpha(c) cells of other fishes, which were only labeled from the ON. The LGC types presently revealed were similar in their morphology to LGCs found in other teleosts supporting the hypothesis of LGC homology across the teleost lineage.     

微波局部照射小鼠睾丸对睾丸、附睾及精子的形态学影响

微波作为环境污染物,其对人类的危害已逐渐受到人们的重视,尤其生殖细胞,不但对微波敏感,而且在人类遗传学中占有独特的地位。本实验应用2450MHz微波局部照射BALB/c小鼠睾丸,于照后不同时间观察睾丸、附睾和精子的形态学改变。结果表明,微波可引起各级生精细胞以浊肿为主的病理学改变,并存在不均一性、持久性、不同的细胞具有不同的敏感性等特点。精子的形态学改变表现为大头畸形增多(P<0.05～0.01),超微结构观察到了一些光镜下难以发现的畸形学表现。一定量的微波对生殖细胞的影响是明确存在的,故对微波的损害应给予积极的防护。     

活性氧对培养神经元形态及存活率的影响

用黄嘌呤氧化酶一次黄嘌呤系统作用于分散培养的鸡胚神经细胞,观察活性氧对神经元形态及存活率的影响。结果表明,活性氧处理后的神经元突起大量脱落,含“空泡”细胞数目增多,大量神经元死亡。在培养液中加入超氧化物歧化酶可以保护神经元免受活性氧损伤,但加入过氧化氢酶后的效应不显著。提示引起神经元损伤的主要因素是超氧阴离子自由基,过氧化氢的直接效应不明显。     

4 种表面形态种植体对支持组织应力分布的影响

目的：观察４种常见不同形态种植体所支持的下颌覆盖义齿,在牙合力作用下其支持组织——牙槽骨及种植体周围的应力分布状况,从生物力学角度为种植体形态设计提供参考。方法：用三维光弹应力冻结切片法,对光滑圆柱形、光滑圆锥形、螺纹圆柱形、螺纹圆锥形４种不同形态种植体所支持覆盖义齿,在牙合力作用下的应力状况进行应力冻结,并在相应部位进行切片观察,以了解不同情况下其支持组织的应力分布状况。结果：种植体不同的表面形态对支持组织应力分布有较大影响,圆柱形种植体比圆锥形种植体,带螺纹种植体比光滑种植体其牙槽骨及骨界面应力值小。结论：不同表面形态的种植体对种植体骨界面及牙槽骨的应力会产生不同的影响。     

Children and Adults as Language Learners: Rules,Variation, and Maturational Change

Here we overview our recent research investigating children and adults’ learning of rules and variation. In all these studies, our findings are that children and adults differ in how they acquire linguistic patterns that are productive, variable, inconsistently used, or lexically restricted. Some of our studies examine children's learning of natural languages; other studies expose learners to miniature languages and then ask them to produce novel sentences or judge their grammaticality. In every case there are important differences between learners as a function of their ages. Young children learn categorical rules and categorically follow patterns that are widespread in natural languages, even when their linguistic input exemplifies these patterns only probabilistically. In contrast, adult learners reproduce the probabilistic patterns of the input. Older children are in between, producing regular patterns somewhat more often than they appear in the input but also acquiring some probabilistic variation. These results suggest that the outcome of learning is quite different at different ages and that many of the properties of natural languages may be shaped by the behavior of children as they learn their native languages.     

外周血异常红细胞形态学检验与诊断的意义

红细胞形态学检查在临床检验中易被忽视。观察红细胞形态一般以外周血涂片较为可靠。由于各类型血液细胞分析仪尚不具备识别红细胞、白细胞和血小板形态的能力,只能用作健康人血液一般检验的筛查,其结果可为是否需要进一步镜检提供筛检信息,尚不能完全代替显微镜对各类血细胞的识别和分类检查。现从红细胞大小、形态、数量、红细胞内血红蛋白含量改变、自身抗体引起红细胞凝集现象以及红细胞结构异常等几个方面进行总结,主要介绍外周血涂片中成熟红细胞的各种形态特征和临床意义,目的是要重视外周血红细胞形态特点,提高诊断水平。     

脊神经丛MR成像的研究进展

脊神经丛各组成支神经细小,周围结构复杂,脊神经丛的MR成像一直是研究的重点和难点。常用于脊神经丛成像的MRI技术包括多种重T₂WI抑脂序列、扩散张量成像(DTI)、扩散峰度成像(DKI)、计量T₂值的T₂-mapping和三维神经鞘信号增高并背景抑制弛豫增强的快速采集定量成像(3D SHINKEI-Quant)、磁化转移率(MTR)成像等。此外,对比剂成像、显微神经成像等技术还有待进一步发展。对上述MRI技术在脊神经丛中的臂丛及腰骶丛中的应用作一综述。