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51.
目的:研究健血升白冲剂对小鼠血液系统的影响。方法:以骨髓细胞计数,白细胞计数和血象为指标,观察健血升白冲剂对正常小鼠和化学及放射损伤小鼠的影响。结果:健血升白冲剂明显增加正常小鼠白细胞计数(P<001),显著改善环磷酰胺诱导小鼠白细胞和骨髓细胞的减少作用(分别为P<005,P<001),并能显著增加60Co放射损伤小鼠骨髓细胞(P<001)和白细胞(P<001)。结论:健血升白冲剂对化学及放射损伤小鼠血液系统有明显的保护及改善作用。是一个有开发价值的药物。 相似文献
52.
The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice. 相似文献
53.
Monolayer cultures of normal human bone cells contain multiple subpopulations of alkaline phosphatase positive cells 总被引:5,自引:0,他引:5
Toshikatsu Matsuyama K. -H. William Lau Jon E. Wergedal 《Calcified tissue international》1990,47(5):276-283
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures
contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative
cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical
method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method,
human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We
defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and
intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values
at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations,
were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels
in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the
intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and
IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with
the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated
with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation.
In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least
two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population. 相似文献
54.
Data on 232 members of a single pedigree, descended from two pairs of original parents, were made available to the participants of Genetic Analysis Workshop 8 (GAW8). In addition to information concerning age and sex, measurements for 10 quantitative traits and genotypes at 22 polymorphic marker loci were also provided for a subset of 193 of these family members. © 1993 Wiley-Liss, Inc. 相似文献
55.
Fumihiko Iwaku 《Journal of bone and mineral metabolism》1989,7(1):7-11
The three dimensional vascular microarchitecture of mercox resin on the lateral surface of parietal bone in Wistar strain
adult male rats (b. w. 260–350 g.) was studied in relation to bone formation by SEM observation of corrosion casts.
The microarchitecture was a single layer of network composed of precapillary artery, capillary and postcapillary vein, which
were serpigious, sometimes joined with the vein from the vascular foramen of bone. The meshes of this network, which were
irregular and varied in size, existed apart from the bone surface.
According to the report of Iwaku and Ozawa (1986), it was reported that the vascular microarchitecture of the bone surface
was very changable during the process of bone remodeling and this network, which was shown on the flat bone surface in this
study, was very similar to one in the resting phase and/or the period in which the bone formation further advanced.
From these facts and the morphological features of the bone surface observed here by SEM, it is suggested that this vascular
network was closely related with the resting stage and/or the period in which bone formation further advanced in bone remodeling. 相似文献
56.
目的 :研究老年人不同疾病时骨密度 (BMD)的分布情况。方法 :用DXADAS 6 0 0EX型骨密度仪对183例老年患者进行左侧远程桡骨加尺骨BMD检测。结果 :内分泌疾病组、消化道疾病组和其它疾病组的患病率分别为 72 7% ,2 0 6 %和 31 4 %。T值比较 :三组差异明显 (P <0 0 0 1)。累积骨丢失率 (ABLR)比较 :前一组明显高于后两组病人 (P <0 0 1)。BMD比较中 ,内分泌和其它疾病组明显低于消化道疾病组 (P <0 0 0 1)。相关分析显示 ,内分泌和消化道疾病组的年龄变化与BMD呈正相关 (r =0 5 19P <0 0 0 1和r =0 5 89P <0 0 0 1) ,内分泌疾病组和其它疾病组的体重变化与BMD呈正相关 (r=0 918P <0 0 0 1和r =0 338P <0 0 0 1)。结论 :老年人骨质疏松 (OP)患病率以内分泌疾病组最高 ,消化道疾病组较低 ;随年龄和体重增加 ,BMD降低加重。 相似文献
57.
目的:了解温州地区人群不同年龄组骨质疏松患病率及同年龄组男女骨质疏松患病的差异,强调早期预防治疗老年人及绝经期妇女骨质疏松的重要性,方法:应用单能量X线(SXA)骨密度仪测量246例正常人的右跟骨骨密度,结果:男性大于60岁组较小于60岁组骨密度(BMD)降低明显(P<0.05);女性50岁以上组与小于50岁组相比,BMD下降差异有极显性(P<0.01);各年龄组男女相比,男性BMD明显高于女性(P<0.05)。结论:女性骨质疏松症的发病大多以绝经后为主,雌激素在维持骨量方面具有重要的作用。SXA检测的跟骨含95%小梁骨,能较好地确定骨质疏松的风险水平,且其具有价廉、简便,快捷,较准确等特点,故不失为一种较好的临床筛查手段。 相似文献
58.
Platelet factor 4 ( PF4) is a negativehematopoietic factor.It can inhibit the prolifera-tion of endothelial cells and hematopoietic stem/progenitor cells,particularly megakaryoryocyticcells,reversibly[1] ,inhibit DNA synthesis,blockcell cycle progression during S phase and reducethe sensibility of normal hematopoietic stem/pro-genitor cells,but not some cancer or leukemia celllines,to cytotoxic drugs and ionizing radia-tion[2 - 3] ,and it also can cause a population in-crease of the stem cel… 相似文献
59.
目的 探讨齿槽裂修复治疗的目的、方法以及治疗时机的选择。方法 查阅1950年至2006年有关齿槽裂修复的文献,归纳文献中报道的不同方法,并评价其各自的优缺点。结果 齿槽裂修复的主要目的:关闭口鼻瘘;建立稳定、连续的上颌骨牙弓;为牙齿萌出提供基础;为上唇和鼻底提供稳定支架。主要治疗方法:植骨术;牵引成骨技术;组织工程骨和生长因子应用;引导骨再生技术。患者最佳的手术治疗时机是9~11岁时混合牙列期。结论 在9~11岁混合牙列期手术,以髂骨松质骨为移植材料被认为是修复齿槽裂的主要手段。牵引成骨技术、组织工程技术和引导骨再生技术,将是齿槽裂修复的新方向。 相似文献
60.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献