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951.
952.
高度近视LASIK治疗中角膜瓣厚度的探讨   总被引:8,自引:0,他引:8  
贺瑞  余顺 《眼视光学杂志》2003,5(3):138-140
目的:探讨高度近视LASIK治疗中角膜瓣厚度问题。方法:142例(283眼)屈光度-9.00~-12.00 D的近视患者用日本NIDEK MK-2000全自动微型板层角膜切割刀切开角膜瓣,厚度71~184μm,激光切削方式一致。将角膜瓣厚度≤110μm分为Ⅰ组,72例(144眼);角膜瓣厚度>110μm分为Ⅱ组,70例(139眼)。对术前、术后屈光度、视力以 及剩余角膜基质床厚度进行比较。结果:术前平均角膜厚度:Ⅰ组为(531.76±30.28)μm(469~575μm),Ⅱ组为(550.66±24.45)μm(506~584μm),两者有明显差异(P<0.05)。术后剩余角膜基质床厚度:Ⅰ组为(333.01±3.30)μm(273~452μm),Ⅱ组为(309.71±31.41)μm(254~368μm),两者有明显差异(P<0.05)。术前屈光度两组分别为(-10.61±1.01)D及(-10.13±0.73)D,两组间无明显差异(P>0.05),术后7 d时分别为(+1.05±1.38)D及(+1.32±1.70)D,两组间也无明显差异(P>0.05),而术后3m Ⅰ组为(-0.13±0.94)D,Ⅱ组为(-1.06±0.96)D,两组有明显的差异(P<0.01)。术前、术后不论UCVA还是BCVA,两组无明显差异(P>0.05)。结论:治疗高度近视时70~110μm的角膜瓣的制作是合理的,并不影响术后视力,对防止术后屈光回退是有效的,对一个有经验的医生来说是可以很好完成的。  相似文献   
953.
观察329块(男193,女136)国人成年跟骨的距关节面形态。其中A型出现率,男为45.08±3.58%,女为41.18±4.22%;B型出现率男为53.89±3.59%,女为58.82±4.22%;C型仅男性出现2例,占1.04±0.73%。成套标本中,距关节面左右对称的,男性90例中有81例,占90.00±3.16%;女性67例中有59例,占88.06±3.96%。经统计学处理,侧别间及性别间均无明显差异。文内结合观察结果提出自己的分型标准及类型,并与以往资料进行了比较。  相似文献   
954.
Abstract. A single dose of rabbit antithymocyte globulin (ATG) was given as the sole immunosuppressive therapy in a model of strong MHC barrier rat heart allotransplantation. PVG/c hearts transplanted to Wistar/Kyoto (WKy) rats resulted in long-term surviving (LTS) grafts and cell-mediated lympholysis (CML) unresponsiveness in 50% of the animals. The effects of ATG treatment on the peripheral blood lymphocyte subsets were studied by flow cytometry. The absolute T-lymphocyte levels decreased to less than 5% and were normalized after 2 weeks. CD8-positive cells were normalized within 1 week, whereas CD4-and CD5-positive cells remained low. Rats with LTS grafts had low levels of all T-lymphocyte markers, especially the CD4-and CD5-positive cells. Rats rejecting their grafts showed an eightfold increase in levels of CD8-and CD5-positive lymphocytes and a twofold increase in levels of CD4-expressing lymphocytes. It is concluded that ATG treatment causes the immediate elimination of large lymphoid populations as well as long-lasting immunomodulation detectable in peripheral blood.  相似文献   
955.
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization.  相似文献   
956.
The effect of iontophoretically applied cholecystokinin (CCK) on neurons of the neostriatum was studied in rats anaesthetized with urethane. The most frequently observed effect of the sulphated octapeptide (CCK-8S) on striatal neurons was excitation. Spontaneously active neurons responded more often to CCK-8S than quiescent cells. Silent, primarily non-responsive neurons could often be stimulated with CCK-8S using glutamate to induce an ongoing discharge. Thus, 45.8% of the 177 neurons studied changed their discharge rate by more than 30%. Certain CCK receptor antagonists could prevent the effect of CCK-8S, fully or at least partly, in the majority of CCK-responsive neurons. The data suggest that cholecystokinin modulates the firing of active neostriatal neurons via the CCKA or the CCKB receptor type. Furthermore, we compared neuronal responses to glutamate with those recorded during concomitant administration of CCK-8S in order to study the interaction of both transmitters, which may be colocalized in striatal afferents. CCK-8S mainly enhanced the excitatory effect of glutamate on striatal neurons, but in several neurons the response to glutamate was reduced. The CCKB receptor antagonist could prevent CCK-8S from increasing the glutamate-induced activation.  相似文献   
957.
This paper describes and discusses issues concerned with therole of the nurse in health promotion work. It represents thefirst phase of a research project designed to explore this role,and presents the evolving philosophical framework for the study.The study is taking place currently in the United Kingdom andhas been made possible by the (first) award of a Post DoctoralNursing Research Fellowship to the project director. Against the backdrop of the World Health Organization's ‘Healthfor All by the year 2000’ (WHO HFA 2000) movement therehave been repeated calls for nurses to be the leaders in healthpromotion. Policy makers and educators have responded to thesecalls by claiming a central role for nursing and putting healthpromotion high on policy and training agendas. Very little attention,however, has been devoted to exploring the legitimacy and developmentof this role in nursing. Generally, nurses seem enthusiasticabout health promotion, and sure that they have a role to play.What is less certain is what this role is. The study seeks toclarify this by exploring policy, behaviour, and attitudes.Policy provides the framework for practice, and operates ata number of levels. In this early paper we review the literatureto explore policy and practice from international to grassrootslevels. We also make some initial observation derived from ourpilot work.  相似文献   
958.
对150名有机磷农药作业工人进行了心电图检查,结果表明,有机磷农药作业工人心电图异常发生率极显著高于对照组(P<0.001)。主要改变为窦性心动过缓,窦性心律不齐,ST—T异常,说明心电图与异常接触有机磷衣药有关,应加强防护措施。  相似文献   
959.
Lung function, smoking, age and mortality data in 158 adult severe alpha1-antitrypsin deficient, PiZZ individuals, followed from 1963 to 1982 were analyzed. Low initial FEV1 value was significantly associated with increased mortality (p < 0.005). A 3 yr mortality rate of 40% was found in individuals whose initial FEV1 values were less than 30% of that predicted. In contrast, the corresponding 3-yr mortality among those whose initial FEV1 values were between 30 and 65% of that predicted was only 7%. Smokers were found to have significantly lower FEV1 levels (p = 0.008) and higher mortality (p < 0.005) than non-smokers. The difference between current and ex-smokers in mortality and FEV1 level were not statistically significant (p = 0.9 and p>0.25, respectively). Cross-sectional analysis of the initial FEV1 values indicated a significant decline (p < 0.005) of FEV1 with increasing age. This decline was greater among smokers than non-smokers. Longitudinal analysis of FEV1 rates of decline in 80 cases with follow-up FEV1 measurements failed to detect any significant differences between smokers and non-smokers, but was performed late in the disease process. The application of these results to the planning of studies on replacement therapy, smoking intervention strategy and longitudinal follow-up is discussed.  相似文献   
960.
运用文献计量分分析法对本刊1992-1995年16期所刊文章作了分析。结果:致突变的文章较多;每篇文章作者平均3.94人,大多集中在高等院校及科研机构,地区分布较广,高产作家尚少;平均引文8.22篇,引文以中、英文期刊为主;文献半衰期为中文4.16年,英文6.93年;有8种核心期刊;自引率较高。与创刊后的前12期(1989-1992)相比:一次性文献比重明显增加,致畸文章比重增加,高产作家相对增多,英文引文增加,英文半衰期缩短近二年半,提示刊物水平有提高趋势。  相似文献   
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