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951.
作者应用免疫荧光技术,对实验性免疫反应性中耳炎模型进行了研究。结果显示:实验动物早期出现前庭功能紊乱;免疫荧光分布于中耳粘膜和前庭囊壁上皮下、耳蜗血管纹和基底膜近蜗轴处;免疫荧光强度测定蜗底多、蜗顶少。 相似文献
952.
The workplace is an important setting for health promotion and provides an ideal opportunity for shaping healthy eating patterns in occupational groups for whom inequalities have been identified (DHSS, 1980). Workplace food/health policies provide an intermediate and pragmatic step towards achieving the dietary targets set out in the Government's white paper Health of the Nation and the most recent COMA report (DoH, 1991,1992). Food/health policies have been widely adopted in the NHS (Gibson & Kallevik, 1990) and preliminary research suggests that they are an effective means of intervention (Wallis & Poulter, 1988; Frost et al., 1991). Industry has been slower to link food and health promotion to a policy making process. Surveys imply that action on healthy eating in companies often originates in the occupational health department and is based on individualistic approaches with little energy being put into preventive activities which would originate in the canteen (Mclnerney & Cooper, 1989; Poulter, 1990). Policies provide a means of balancing the environmental and educational paradigms of health promotion. If food/health policies are to grow in the private sector then industry has to be convinced that the benefits Justify the costs. Some philanthropic employers are motivated by interests other than financial gain, but others are commercially led. There is little hard evidence to demonstrate that any type of employer-sponsored healthy eating initiative provides a favourable return for investment. It has been ‘guesstimates’ and extrapolation from other situations which have provided the justification for UK companies to allocate any resources towards addressing food/health issues. In April 1990 the National Grid Company adopted a comprehensive food/health policy. This paper draws on the experiences in developing and implementing the policy document to discuss the issues around evaluative activity in a commercial setting. Views are expressed on the feasibility of measurement and the value of the informaton collected. One aim of the future should be to research this under-examined area to establish a solid body of information. This would raise the level of debate from one which is currently based on anecdotal evidence to a sounder scientific footing and, therefore, ensure the future growth of such policies in the corporate sector. 相似文献
953.
Critchley Hilary O.D.; Bailey Deborah A.; Au Chak L.; Affandi Biran; Rogers Peter A.W. 《Human reproduction (Oxford, England)》1993,8(10):1632-1639
The bleeding problems experienced by users of subdermal levonorgestrelimplants (Norplant) remain unexplained. The aim of the presentstudy was to investigate the oestrogen (ER) and progesteronereceptor (PR) distribution in levonorgestrel-treated endometrialbiopsies from 31 subjects recruited in Jakarta, Indonesia, andto compare the sex steroid receptor immunostaining with thatof endometrium from 58 normally cycling women from Melbourne,Australia. Sex steroid receptor immunoreactivity was additionallycompared with days of exposure to subdermal levonorgestrel,serum oestradiol and progesterone levels and days of bleedingduring a 90-day reference period. An immunohistochemical techniquewith an alkaline phosphatase anti-alkaline phosphatase (APAAP)detection system for use in formalin-fixed paraffin wax embeddedendometrial tissue was employed. Significantly greater meanimmunostaining scores of stromal PR were observed in Norplantcompared with control endometrium at all stages across the cycle.No significant correlations were demonstrated between sex steroidreceptor immunostaining and days of exposure to subdermal levonorgestrel,serum oestradiol or progesterone concentrations or days of bleedingduring a 90-day reference period. Whether the elevated stromalPR immunostaining in Norplant-treated endometrium is a consequenceof increased synthesis or reduced turnover of receptor remainsunclear. As yet it is undetermined whether increased PR immunoreactivitycorresponds to an increase in number of functional PR. 相似文献
954.
Ayala Stabholz Anne A. Nicholas Grenith J. Zimmerman Ulf M. E. Wikesjö 《Journal of clinical periodontology》1998,25(10):794-800
Abstract. 15 adults, each providing 4 non-adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm. volunteered for a randomized, split-mouth, double-blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%). TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post-irrigation mechanical plaque control was supported by 2× daily CHX rinses throughout the 12-week observation interval. Recordings of oral hygiene (PlI), gingival health (GI). bleeding on probing (BoP). probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre-irrigation. and at 1, 2, 4, 6, 8, 10, and 12 weeks post-irrigation. Mean post-irrigation PlI was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre-irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre-irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post-irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre-irrigation for TTC10. CHX and control sites over the 12-week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post-irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a rôle in the management of adult periodontitis. 相似文献
955.
Homeostasisof11ematopoiesisiscontrollednotoillybytheproliferationanddifferentiationofcells,butalsobycelldeath.Inadditiontolossofcontrolofcellproliferation,disruptionofapoptosis--inducedf[lnctionalsocontributestotumordevelopment.Althoughdiversesignalscaninduceapoptosisinawidevarietyofcelltypes,anumberofevolutionarilyconservedgenesregulateafinalcommoncelldeathpathway,thatisconservedinmanyspeciesfromwormstohumansll].Thehcf--2proto--oncogeneisoneofthecrucialapoptosisantagonizinggenes.Highlevelofhc… 相似文献
956.
957.
Studies in rats in vivo and in isolated hepatocytes from the same species and strain of animal in vitro with the hepatotoxicant hydrazine have shown that despite measuring the same parameters in each system, the effects do not always show a quantitative or qualitative correlation. For example depletion of glutathione and ATP occurred in both systems but required a much higher concentration of hydrazine in vitro. The effects on triglyceride levels, citrulline synthesis and taurine levels in vivo were not observed in vitro and the inhibition of urea synthesis and cytotoxicity in vitro were not observed in vivo.Inhibition of protein synthesis proved to be the marker which showed the best correlation, occurring at a similar hydrazine concentration in vitro and in vivo although not to the same extent.The situation with other toxicants is variable, in some cases correlation is good, in others modification of conditions in vitro are required. 相似文献
958.
New insights into the regulation of ICAM-1 gene expression 总被引:2,自引:0,他引:2
959.
三袖套管法大鼠肺移植 总被引:12,自引:2,他引:10
我们将血管套接技术用于大鼠肺移植中。在肉眼下,完成肺动静脉及支气管的吻合。在连续6例手术中,手术平均时间61±4分钟,移植物总缺血时间17±3分钟,手术时间缩短至国外同类手术的1/4,缺血时间缩短至同类手术的1/3。同时手术成功率达到75%(6/8),手术后生存率100%。行对侧肺切除术后,血气分析正常,显示了移植肺良好的气体交换功能 相似文献
960.
乙型肝炎肝内血管病变免疫组织化学观察 总被引:2,自引:0,他引:2
目的 研究乙型肝炎(乙肝)肝内血管病变与肝病变的关系。方法 270例肝活检标本取自住院乙肝患者,选择10例大致正常肝组织作对照。石蜡包埋,4μm切片,除依次作HE、弹力、网状及胶原杂色外另用特异性平滑肌肌动蛋白单克隆抗生进行免疫组织化学标记,结果 正常肝组织α-SMA仅在原有的肝内动、静脉及胆管壁表达。乙肝病变较轻组肝组织α-SMA示阳必表达占75%;乙肝病变较重及肝硬变组肝组织α-SMA示强阳性 相似文献