Periodontal conditions among the middle-aged and the elderly in Hong Kong

Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984.     

Morphological types of ganglion cells in the dog and wolf retina.

The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat.     

Influences of context on early writing development

Research on children's early writing development in the past has focused primarily on product and process. In reviewing the more recent research on early writing development, however, a new focus of context emerges. Occurrences of literacy are now being observed in the home, the school, and the community. With this new emphasis, comes the task of defining context. A definition of context reflects theoretical perspectives, areas of research interests, and types of methodologies employed in conducting research. Therefore, the purpose of this article is to address the following aspects of context: #op1#cp multidiscipline perspectives and definitions of context, #op2#cp contextual shifts observed between the home and the school, #op3#cp contextual factors present when learning how to write, and #op4#cp pedagogical implications for curriculum development.     

Surface behavior of axolemma monolayers: Physico-chemical characterization and use as supported planar membranes for cultured Schwann cells

The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties. © 1993 Wiley-Liss, Inc.     

重组人红细胞生成素治疗肾性贫血的临床分析

目的　观察重组人红细胞生成素 (RhEPO)对肾性贫血的治疗作用。方法　根据使用EPO剂量的不同将 39例慢性肾衰竭并血液透析病人分成 4组 ,观察治疗后 2、4、12个月时与治疗前 (0月 )相比红细胞数 (RBC)、红细胞比积 (Hct)及血红蛋白含量 (Hb)的变化。结果　 2 4例使用EPO10 0 - 15 0IU/ (kg·w) (6 0 0 0IU/w - 90 0 0IU/w) ,治疗后RBC、Hct、Hb较治疗前有显著升高 (P≤ 0 .0 0 1) ;5例使用EPO5 0IU/ (kg·w) (30 0 0IU/w) +间断输血患者 ,其RBC、Hct、Hb升高不显著 ;10例不用EPO而单纯输血患者 ,其RBC、Hct、Hb无明显变化 (P >0 .0 5 )。结论　EPO能较好地纠正肾性贫血 ;单纯输血不能治疗肾性贫血     

铲状电极经尿道前列腺电汽化切割术120例报告

目的：探讨铲状电极经尿道前列腺电汽化切割术中的手术经验及疗效。方法：总结了120例经尿道前列腺电汽化切割手术的治疗资料。结果：术后随访1月～2年，120倒手术患者118例治愈，2例于术后出现急性肾衰，经保守对症治疗痊愈，2例出现压力性尿失禁，经对症治疗好转。结论：铲状电极行前列腺组织的汽化切割，优于滚轮汽化电极或电极弧，术中术后出血少，术中术野清晰，安全可靠。     

子宫内膜增生性病变与子宫内膜癌的超声诊断价值

目的:探讨子宫内膜增生性病变与子宫内膜癌的超声鉴别诊断及内膜癌肌浸程度的估价.方法:采用术前B超、术后大体标本观察测量,对123例子宫内膜病变患者的声像图资料进行分析并与手术后病理结果对照.结果:①子宫内膜病变者子宫三径之和平均值均大于正常值;②58.6%的子宫内膜增生过长病变患者内膜形态以条形、梭形和正常形态回声;35%的Ⅱ期以上子宫内膜癌患者内膜回声以积液为主兼有其它图像类型;③大于50岁患者不同病理类型病变的子宫内膜平均厚度均超过其正常内膜厚度值,但无明显的规律性.小于50岁的患者内膜增厚主要以子宫内膜增生过长病变为主占48%;④通过超声测量子宫内膜厚度判断子宫内膜癌浅肌层和深肌层浸润符合率均为71.4%.结论:超声检查对判断子宫内膜病变病理类型有一定帮助,内膜厚度、内膜形态、回声特点、及内膜与肌层间的关系等,仅提示病变存在的可能性,要鉴别病变的良恶性、肌层浸润深度,须根据上述回声特点进行综合分析.     

高强度超声对犬前列腺组织损伤的实验研究

目的　探讨经尿道高强度超声 (transurethralhighintensityultrasound ,TUHIU)治疗良性前列腺增生症 (benignprostatichyperplasia ,BPH)的有效性和可行性。方法　对犬前列腺进行TUHIU辐照处理 ,辐照后不同时期处死动物以观察其急性、亚急性和慢性期大体及组织病理变化。同时观察辐照前后影像学变化。结果　TUHIU辐照前前列腺部尿道平均最大宽度为 0 66± 0 12 ( x±s)cm ,辐照 3周后前列腺部尿道平均最大宽度为 2 11± 1 0 7cm ,较辐照前显著增宽。辐照后可见靶区内尿道周围腺体发生凝固性坏死 ,3 0～ 60天后坏死组织脱落尿道呈囊腔状。光、电镜下均可见腺上皮及基质细胞发生均匀性凝固性坏死。辐照后经腹B超示前列腺内部出现液性暗区 ,前列腺呈囊性改变。辐照后即刻各犬均出现短暂性尿潴留、尿频、尿线变细 ,1月后恢复正常。结论　TUHIU可破坏前列腺组织 ,明显增加前列腺部尿道宽度。