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971.
目的 研究虹膜夹型有晶状体眼人工晶状体(iris-claw phakic intraocular lens,ICPIOL)植人术后对比敏感度(contrastsensitivity,CS)的变化。方法 2005年5月至12月于温州医学院附属眼视光医院和中山大学中山眼科中心接受ICPIOL(Verisyse,美国AMO公司)植入术的高度近视眼患者12例(23只眼),分别在术前、术后1、3、6个月采用CS测试灯箱(CSV-1000型,美国Vector Vision公司)检查暗视状态下无/有眩光时的对比敏感度函数(contrast sensitivity function,CSF)。结果 术后1、3、6个月等效球镜度数分别为(-0.60±0.77)D,(-0.48±0.77)D,(-0.34±0.53)D,与术前(-15.53D±3.65D)差异均有显著统计学意义(P均〈0.001),最佳矫正视力(IogMAR)分别为0.064-0.12,0.02±0.09,-0.003±0.08,与术前(0.21±0.12)差异均有显著统计学意义(P均〈0.001)。术后各空间频率的CS与术前比较有增高趋势。术后3个月6、12、18周/度的CS在无眩光时和有眩光时均明显提高(P均〈0.01),开始接近正常范围。术后3、6个月在各空间频率上CS差异均无统计学意义(P均〉0.05)。结论 ICPIOL植入术矫治高度近视眼可以使CSF恢复到接近正常范围,显著改善视功能,是一种适用于高度乃至超高度近视眼的可供选择的屈光手术。 相似文献
972.
Zhang Deli Chen Shulan 《宁夏医科大学学报》1987,(2)
Sinoatrial node electrogram (SNE) was recorded successfully in recent years, using transvenous electrode catheter. Via SNE and intratrialelectrogram (IEG), one could measure sinoatrial conduction time(SACT) directly, observe sinoatrial node (SN) potential changes in cadiac cycles, diagnose some sinus arrhythmias which couldn't be confirmed by surface ECG. All these could offer accurate evidence for differential diagnosis of sick sinus syndrome (SSS). The authors recommend a modified method for the location of the electrode catheter, by which one can increase success rate of obtaining stable SNE. Using this method, the authors recorded SNE in 10 cases with SSS successfully. 相似文献
973.
冠状动脉造影术,使冠心病的诊断、治疗水平明显提高。但床上排尿困难是术后常见的护理问题,采用常规的方法,效果不佳,常需导尿术解决,既增加了患者的痛苦,又增加了护理工作量。我科2003年3月~2006年10月采取开塞露肛注刺激直肠诱发排便-排尿反射,较好地解决了床上排尿困难的问题。并与常规诱导排尿的方法进行了比较,现报告如下。临床资料对象选择冠状动脉造影术后排尿困难者60例,其中男性42例,女性18例,年龄20~78岁,平均53岁,随机分为对照组和观察组各30例,两组年龄、性别差异无显著性,具有可比性。方法(1)观察组:给予开塞露肛注排便以诱导… 相似文献
974.
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
975.
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
976.
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
977.
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
978.
Homeostasisof11ematopoiesisiscontrollednotoillybytheproliferationanddifferentiationofcells,butalsobycelldeath.Inadditiontolossofcontrolofcellproliferation,disruptionofapoptosis--inducedf[lnctionalsocontributestotumordevelopment.Althoughdiversesignalscaninduceapoptosisinawidevarietyofcelltypes,anumberofevolutionarilyconservedgenesregulateafinalcommoncelldeathpathway,thatisconservedinmanyspeciesfromwormstohumansll].Thehcf--2proto--oncogeneisoneofthecrucialapoptosisantagonizinggenes.Highlevelofhc… 相似文献
979.
980.
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