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31.
郑巧  张琪 《国际眼科杂志》2019,19(9):1503-1506

共焦显微镜(confocal microscopy, CM)检查作为一种“活体组织学检查”方法,以其实时、无创、快速、高清的特点,在角膜生理、病理研究及疾病诊断、病情评估、随访等方面显示出优越性,已在眼科临床及科研中得到广泛应用。本文将对CM在感染性角膜疾病、变性性角膜疾病及全身疾病所致角膜病变中应用的新进展作一综述。  相似文献   

32.

目的:对比观察5种人工晶状体(IOL)计算公式在角膜屈光术后白内障患者IOL屈光度计算中的准确性。

方法:前瞻性系列病例研究。收集2021-09/2023-03就诊于济南明水眼科医院的既往行角膜屈光手术矫正近视的白内障患者23例34眼,其中准分子角膜切削术(PRK)手术史1例1眼,准分子原位角膜磨镶术(LASIK)术后22例33眼。白内障术前采用IOL Master 700测量眼生物学参数; Pentacam眼前节分析系统测量角膜真实净屈光力(TNP); 眼前节OCT测量净角膜屈光力(NCP)、角膜后表面屈光力、角膜厚度(CCT)。采用Shammas公式、Haigis-L公式、Potvin-Hill Pentacam公式、OCT公式、Barrett True K公式进行IOL度数计算后综合选择合适的IOL度数。术后1 mo在客观验光的基础上行主觉验光获得术后实际屈光状态,根据术后验光结果计算5种公式的屈光预测误差(RPE),其绝对值为屈光绝对误差(RAE),比较RPE与0的差异及不同公式间RPE、RAE的差异,并统计RAE≤0.5 D、≤1.0 D的眼数所占百分比。

结果:5种公式计算所得的RPE与0比较均无差异(均P>0.05)。5种计算公式的RPE、RAE整体无差异(F=0.554,P=0.696; H=4.402,P=0.354); Potvin-Hill Pentacam公式、Barrett True K公式的RAE在≤0.5 D内的眼占比分别为26眼(76%)、24眼(71%),在≤1.0 D内的眼占比均为33眼(97%)。

结论:Barrett True K 公式、Potvin-Hill Pentacam公式在角膜屈光术后白内障患者IOL屈光度计算中表现出较高的预测性。由于此类人群角膜屈光力存在差异,IOL度数计算问题仍需要进一步研究,临床上建议多种公式综合考虑。  相似文献   

33.
AIM: To investigate the clinical features of the ocular surface in patients with different degrees of myopia. METHODS: A cross-sectional study was conducted involving 122 participants with myopia in Beijing Tongren Hospital from February to June, 2023. After completing the Ocular Surface Disease Index (OSDI) score scale, measurements were taken for refraction, biometric parameters and ocular surface parameters. The prevalence, severity and related parameters of the dry eye among different groups based on axial length (AL) were compared. Correlation analysis was performed between ocular surface parameters and refraction/biometric measurement parameters. RESULTS: Statistically significant differences were observed in refractive error, corneal thickness, anterior chamber depth, and subfoveal choroidal thickness among the groups (all P<0.05). With the increase in AL, the incidence and severity of dry eye increased significantly (P<0.05). Moreover, the tear film break-up time (BUT) shortened (P<0.05), and the corneal fluorescein staining (CFS) points increased significantly (P<0.05). OSDI scores were positively correlated with AL and spherical equivalent (SE; both P<0.05); BUT was negatively correlated with AL, SE, and corneal astigmatism (AST; all P<0.05); Schirmer I test (SIT) results were negatively correlated with AL and SE (both P<0.05). CONCLUSION: AL elongation is a risk factor for dry eye onset in myopic participants. The longer the AL, the more severe the dry eye is, with the increased CFS spots and tear film instability. Additionally, SE and AST exhibit negative correlations with dry eye symptom scores and ocular surface parameters.  相似文献   
34.
Porcine epidemic diarrhea (PED), characterized by diarrhea, vomiting, and dehydration, is an acute enteric infectious disease of pigs. The disease is caused by porcine epidemic diarrhea virus (PEDV), which infects the intestinal mucosal surface. Therefore, mucosal immunization through the oral route is an effective method of immunization. Lactic acid bacteria, which are acid resistant and bile-salt resistant and improve mucosal immunity, are ideal carriers for oral vaccines. The S1 glycoprotein of PEDV mediates binding of the virus with cell receptors and induces neutralizing antibodies against the virus. Therefore, we reversely screened the recombinant strain pPG-SD-S1/Δupp ATCC 393 expressing PEDV S1 glycoprotein by Lactobacillus casei deficient in upp genotype (Δupp ATCC 393). Mice were orally immunized three times with the recombinant bacteria that had been identified for expression, and the changes of anti-PEDV IgG and secreted immunoglobulin A levels were observed over 70 days. The results indicated that the antibody levels notably increased after oral administration of recombinant bacteria. The detection of extracellular cytokines on the 42nd day after immunization indicated high levels of humoral and cellular immune responses in mice. The above results demonstrate that pPG-SD-S1/Δupp ATCC 393 has great potential as an oral vaccine against PEDV.  相似文献   
35.
本文选取32个小分子化学成分和9个天然产物化学成分为训练集,利用Dragon软件计算分子描述符,应用WEKA软件中CfsSubsetEval评价方法和BestFirst-D1-N5搜索方法进一步筛选描述符,利用Linear Regression方法建立了分子结构与其血清蛋白结合常数值logK的定量结构-性质相关性模型(相关系数为0.9557)。应用该模型对10个绿原酸类化合物的logK进行预测,结果显示绿原酸的logK预测值为4.51,与文献报道的logK值在4~7范围内基本相符。研究结果为进一步探讨绿原酸与血清蛋白的结合情况提供指导,为研究药物与血清蛋白的结合提供思路。  相似文献   
36.
驳骨煎剂促进骨折愈合的实验研究   总被引:19,自引:6,他引:13  
为探讨驳骨煎剂促进骨折愈合的作用机理。选用体重20-30g的NIH小白鼠120只,雌雄各半,随机分为正常组,给药组、对照组。除正常组外,其它各组均采用定点手法折骨术造成小鼠右下肢胫骨中段闭合性骨折,术后7、14、21、28天分批处死小鼠,处死前48小时,经腹腔注射同一批号0.2ml^45Ca-CaCl2溶液,48小时后,断头取向,并解剖出左右胫骨,测定骨痂生长状况及钙沉 积量的变化。结果显示,给药  相似文献   
37.
乔俭 《河南中医》2010,30(3):234-237
乔振纲老中医认为癌瘤的基本病机为"正虚邪实"。治疗强调整体调理,扶正固本,区分癌瘤不同部位和病程的不同阶段,辨证用药。不能囿于癌灶,不能拘泥一方,更不能不顾体质虚实,一味堆砌解毒抗癌药物。主张轻剂缓图,不能猛浪从事。  相似文献   
38.
39.
目的:评价京尼平交联治疗兔大泡性角膜病变的效果.方法:将已建立大泡性角膜病变动物模型的9只雌性新西兰白兔随机分为3组:治疗组(n=3),对照组(n=3),空白对照组(n=3).其中治疗组:刮除角膜上皮后,应用0.25%的京尼平浸泡实验眼角膜40min(24℃);对照组:刮除角膜上皮后,应用生理盐水浸泡实验眼角膜40min(24℃);空白对照组:不进行任何处理.处理后2wk内进行以下检查:裂隙灯检查、中央角膜厚度(CCT)测量、体质量和应激反应评估、组织学检查和利用原位末端转移酶标记技术(TUNEL法)检测基质层细胞凋亡.结果:与对照组和空白对照组相比,治疗组角膜水肿明显减轻、角膜上皮逐渐修复完整、角膜大泡消失、中央角膜角膜厚度显著下降(P<0.05)、体质量显著增加(P<0.05).治疗组的实验动物活动性较处理前增加,反抗行为减少,攻击性减低.治疗组角膜基质层胶原纤维排列更为紧致、规则,可见蓝色条索状交联产物.治疗组角膜基质层均偶见凋亡细胞,对照组及空白对照组未明显见凋亡细胞.结论:京尼平交联治疗可使兔大泡性角膜病变角膜水肿减轻,疼痛症状缓解,其可能的机制为京尼平交联使角膜基质层胶原纤维排列紧密,从而阻止角膜水肿和大泡的形成.  相似文献   
40.
The first gout attack in a hyperuricaemic patient may be regarded as a nucleation event which is caused by monosodium urate monohydrate (MSUM) deposition in the synovial fluid. The effect of Tailor-Made Inhibition (TMI) may be effective as drugs for the prevention of aberrant nucleation and crystallization. Therefore, the understanding of the underlying mechanisms in inhibiting the MSUM nucleation by TMI has proven to be of great significance. Yet most of the published studies about nucleation inhibition have tended to focus on simpler molecular models with a hydrogen-bonded acceptor and donor, which may be not suitable for the uric acid molecule with multiple hydrogen-bonded acceptors and donors under physiological conditions. Herein, the mechanisms of nucleation inhibition of MSUM were explored in a simulated biological environment (0.15 M Na+ and pH 7.40) in the presence and absence of TMI. And the evidence of nucleation inhibition by TMI in solution and the amorphous form of MSUM was investigated by HNMR, IR, Raman, PXRD, Dynamic light scattering (DLS), induction time measurements, and density functional theory (DFT) calculations. Results showed that the inhibition comes from a combination of kinetic and thermodynamic effects, with an impact of kinetics as the TMI inhibition effects far exceeded what could be accounted for by changes in usual factors of classical nucleation theory. The data demonstrated that the complex between urate and TMI disturbed the formation of two-dimensional sheets of sodion and purine rings parallel to the (011) plane and further impeded the formation of a three-dimensional structure with aromatic stacking interactions in solution. To our knowledge, the nucleation inhibition of TMI is achieved by suppressing interplanar stacking, which is a mechanism proposed for the first time.

Xanthine, a tailor-made inhibitor, could suppress nucleation in the crystallization of gout pathology by blocking the dominant interplanar accumulation in a solution.  相似文献   
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