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1.
目的探讨豚鼠眼球形觉剥夺后恢复期的生物学参数变化规律。方法普通级2~3周龄豚鼠30只,随机分为两组:①实验组:20只,右眼采用半透明眼罩遮盖进行形觉剥夺4周,随后去遮盖3周,左眼作为自身对照;②正常对照组:10只,双眼不进行任何干预,开放饲养7周。形觉剥夺前、形觉剥夺4周后及去遮盖后第2、6、10、14和21天,测量豚鼠双眼生物学参数:睫状肌麻痹后行带状光检影测量屈光度;A超测量前房深度、晶体厚度和眼轴长度,计算出玻璃体腔长度。结果经过4周形觉剥夺,实验组豚鼠右眼向近视漂移,屈光度为(-2.88±2.30)D,诱导了(-5.50±1.9)D相对近视。去遮盖后,豚鼠右眼重新正视化,屈光度恢复的快速期发生在6 d内,14 d时双眼屈光度差值差异无显著性(t=-2.049,P=0.080),为(-0.18±0.26)D;右眼玻璃体腔长度缩短,14 d时双眼玻璃体腔长度差值差异无显著性(t=1.652,P=0.14),为(0.0234±0.0400)mm;右眼眼轴长度缩短,14 d时双眼眼轴长度差值差差异无显著性(t=1.443,P=0.192),为(0.0183±0.0359)mm。与正常对照组右眼相比,去遮盖6 d,屈光度差异为(-0.48±0.36)D,差异无显著性(t=-1.325,P=0.206),而2 d时玻璃体腔和眼轴长度差异分别为(0.0961±0.0630)mm、(0.0621±0.0386)mm,差异无显著性(t=1.652,P=0.14;t=1.607,P=0.125)。结论 2~3周龄豚鼠去除形觉剥夺后可以重新进行正视化,伴随玻璃体腔和眼轴长度缩短;去遮盖6 d内为眼生物学参数恢复的主要时期。  相似文献   

2.
目的探讨高度选择性M4受体阻滞剂MT3对豚鼠形觉剥夺性近视的抑制作用及其潜在作用机理。方法 3周龄豚鼠随机分为三组:对照组、形觉剥夺组、形觉剥夺+MT3组。实验前后使用带状光检影测量屈光度,A超测量眼生物学参数,RT-PCR检测视网膜和脉络膜中TGF-β2的mRNA相对表达量。结果与对照组右眼相比,形觉剥夺+MT3组豚鼠右眼形成了(-1.44±0.50)D相对近视(右眼-左眼),玻璃体腔和眼轴长度分别延长(0.10±0.02)mm和(0.14±0.07)mm(P=0.001,P0.001,P0.001),但近视量、玻璃体腔和眼轴长度增加量均显著小于单纯形觉剥夺组(P0.001,P0.001,P0.001)。单纯形觉剥夺可引起视网膜和脉络膜TGF-β2的mRNA相对表达量下调(P0.001,P=0.014);而玻璃体腔注射MT3可导致形觉剥夺眼视网膜和脉络膜TGF-β2的mRNA相对表达量上调(P0.001,P0.001)。结论 MT3能抑制豚鼠形觉剥夺性近视的形成,其可能通过上调视网膜和脉络膜中TGF-β2的mRNA水平而发挥作用。  相似文献   

3.
将乙酰胆碱(ACh)注入麻醉家兔脊髓蛛网膜下腔,观察其对心血管活动的影响。结果表明:(1)脊髓蛛网膜下腔注射50~100μg ACh可使血压下降,心率减慢;(2)预先由脊髓蛛网膜下腔注射阿托品,可阻断ACh引起的降压和降心率作用;(3)脊髓蛛网膜下腔注射六甲双铵、酚妥拉明或心得安均不能阻断上述ACh的心血管反应;(4)切断两侧颈部迷走神经,ACh不再使心率减慢,但其降低血压的作用不受到任何影响。 脊髓中ACh水平升高可通过激活胆碱能M-受体引起血压下降和心率减慢。ACh的这种降压作用既没有中枢肾上腺素能受体活动参与,也不是通过迷走神经实现的,可能是由于脊髓交感血管中枢紧张性降低所造成的。  相似文献   

4.
目的:探讨大鼠穹窿下器官(SFO)对外周肾小管钠泵的调节作用及机制。方法:在SFO分别微量注射血管紧张素II(AngII),其中氯沙坦(losartan)组先用AngII的1型受体(AT1)拮抗剂losartan预处理后再注射AngII 放免法检测血清中内源性洋地黄样物质(EDLS)的水平和血浆AngII水平 微分离大鼠肾脏单根近球小管,液闪法测定小管管周膜钠泵活性。结果:①SFO注射AngII后,血清中EDLS在15 min开始升高,约60 min达高峰 ②肾近球小管钠泵活性在SFO注射AngII后30 min和60 min都显著下降 ③用losartan预处理SFO后,再注射AngII,血清EDLS水平升高和小管钠泵活性下降的效应被显著削弱。结论:大鼠SFO注射AngII后,肾近球小管钠泵活性将下降,原因可能与SFO注射AngII后,激动SFO的AT1受体,直接或间接升高血清EDLS水平有关。  相似文献   

5.
目的:探讨I型胶原α1链(collagen I alpha-1,COL1A1)基因和类胰岛素生长因子-1 (insulin-like growth factors-1, IGF-1)基因与中国北方汉族人群高度近视的相关性。方法:收集2011年10月~2017年1月经我院眼科视光学中心诊疗的高度近视眼患者286例(病例组)及正常对照者201例(对照组),病例组按照眼球中轴长度分为A组(眼轴长度≥27 mm)126例和B组(眼轴长度27 mm)160例。用血液基因组DNA提取试剂盒提取受试者外周静脉抗凝血中的基因组DNA,采用多重PCR反应和基因测序得到目标片段COL1A1基因的多态位点rs2075555、rs2075554、rs2269336、rs1107946、rs1007086,IGF-1基因的多态位点rs12423791、rs10860860、rs2946834、rs6214的碱基序列,用卡方检验和Logistic回归分析的方法分析病例组和对照组之间各基因分布的差异。结果:病例组和正常对照组COL1A1基因的单核苷酸多态性位点的基因型频率和等位基因频率均无显著性差异(P0.05)。病例组和正常对照组IGF-1基因的rs12423791位点的基因型频率和等位基因频率有统计学差异(P=0.016),其他3个位点的单核苷酸多态性位点均无显著性差异(P0.05)。病例A组和对照组及A组和B组之间COL1A1基因的5个单核苷酸多态性位点分布均无显著性差异(P0.05),IGF-1基因的rs12423791位点有统计学差异(P=0.033)。结论:胶原类基因COL1A1的多态性与中国北方汉族人群高度近视的发生无显著相关性,IGF-1基因的rs12423791位点的多态性与中国北方汉族人群高度近视的发生有显著相关性。  相似文献   

6.
Pinghui Wei  Guoge Han  Yan Wang 《Proteomics》2023,23(18):2200325
The retinal pigment epithelial (RPE)/choroid complex regulates myopia development, but the precise pathogenesis of myopia remains unclear. We aimed to investigate the changes in RPE/choroid complex metabolism in a form deprivation myopia model after dopamine D2 receptor (D2R) modulation. Guinea pigs were randomly divided into normal (NC), form deprivation myopia (FDM), and FDM treated with dopamine D2R antagonist groups. Differential metabolites were screened using SIMCA-P software and MetaboAnalyst metabolomics analysis tool. Functions of differential metabolites were analyzed using KEGG enrichment pathways. Relative to the NC group, 38 differential metabolites were identified, comprising 29 increased metabolites (including nicotinic acid, cytosine, and glutamate) and 9 decreased metabolites, of which proline exhibited the largest decrease. Pathway analysis revealed regulation of arginine/proline and aspartate/glutamate metabolism. Intravitreal D2R antagonist injection increased proline concentrations and activated arginine/proline and purine metabolism pathways. In sum, D2R antagonists alleviated the myopia trend of refractive biological parameters in form deprivation myopic guinea pigs, suggesting the involvement of dopamine D2R signaling in myopia pathogenesis. The RPE/choroid may provide glutamate to the retina by activating proline metabolism via metabolic coupling with the retina. Dopamine D2R antagonism may modulate proline/arginine metabolic pathways in the RPE/choroid and regulate metabolism, information presentation, and myopia.  相似文献   

7.
Objectives:To investigate whether patients with radiologically positive spondyloarthritis (SpA), suffer from comorbid fibromyalgia (FM), and to explore the impact of FM on the clinical manifestations and blood test results of patients with ankylosing spondylitis (AS).Methods:121 patients with spondyloarthritis (SpA) were enrolled in the study. The body function of the patients was evaluated using the Bath Ankylosing Spondylitis Functional Index (BASFI); the mental health was evaluated using the Hospital Anxiety and Depression Scale (HADS).Results:Out of 121 patients with SpA, 111 patients were with axial spondyloarthritis (axSpA) and 11 patients with FM; 10 patients with peripheral SpA and 1 patient with FM. In axSpA, 107 were radiologically positive axSpA patients, 11 were complicated by FM, and 4 were radiologically negative axSpA (nr-axSpA). Among radiologically positive axSpA, the proportion of female patients in the FM group was higher (63.6%, P<0.05). The ASDAS-C-reactive protein (CRP), ASDAS-erythrocyte sedimentation rate (ESR), BASDAI, BASFI, and HADS-anxiety score, and HADS-depression score of the FM group were all significantly higher than those of the non-FM group.Conclusions:When determining the treatment plan for SpA, the possibility of coexistence of FM should be considered, and adjuvant treatment should be given when necessary.  相似文献   

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10.
In order to meet the demands of myopia prevention, as well as the increasing needs of measurement for refractive and cataract operations in China, a new axial length (AL) measurement system combining an improved Twyman-Green interferometer with digital signal processing has been established. The ALs of 33 eyes of different optical refractive subjects (−8.50 ~ 0.50 D) were measured with the New AL and intraocular lens (IOL) master. The repeatability of measurements with the New AL was assessed using coefficient of variation (CoV) and intra-group correlation coefficient (ICC). Comparison, correlation, linear regression and agreement of AL between devices were analyzed. There was good repeatability (CoV = 0.0617%, ICC = 0.9999) with the New AL and great agreement has been obtained with both devices. These show that the New AL is capable of providing precise AL values over the normal AL range compared to the IOL master, and indicate that the New AL developed can be used for routine clinical AL measurements.  相似文献   

11.
In Bayesian phylogenetics, confidence in evolutionary relationships is expressed as posterior probability--the probability that a tree or clade is true given the data, evolutionary model, and prior assumptions about model parameters. Model parameters, such as branch lengths, are never known in advance; Bayesian methods incorporate this uncertainty by integrating over a range of plausible values given an assumed prior probability distribution for each parameter. Little is known about the effects of integrating over branch length uncertainty on posterior probabilities when different priors are assumed. Here, we show that integrating over uncertainty using a wide range of typical prior assumptions strongly affects posterior probabilities, causing them to deviate from those that would be inferred if branch lengths were known in advance; only when there is no uncertainty to integrate over does the average posterior probability of a group of trees accurately predict the proportion of correct trees in the group. The pattern of branch lengths on the true tree determines whether integrating over uncertainty pushes posterior probabilities upward or downward. The magnitude of the effect depends on the specific prior distributions used and the length of the sequences analyzed. Under realistic conditions, however, even extraordinarily long sequences are not enough to prevent frequent inference of incorrect clades with strong support. We found that across a range of conditions, diffuse priors--either flat or exponential distributions with moderate to large means--provide more reliable inferences than small-mean exponential priors. An empirical Bayes approach that fixes branch lengths at their maximum likelihood estimates yields posterior probabilities that more closely match those that would be inferred if the true branch lengths were known in advance and reduces the rate of strongly supported false inferences compared with fully Bayesian integration.  相似文献   

12.
Summary The location of occupied and unoccupied progesterone receptors (PR) in chick oviduct cells was studied by immuno-electron microscopy with the use of a highly specific polyclonal anti-PR antibody and pre-embedding modifications of the peroxidase-anti-peroxidase-(PAP-) or immunogold-silver methods. Both methods revealed a nuclear localization of the PRs. The location of the PR in the nucleus was studied in detail by means of the immunogold-silver method. The most intense labelling for unoccupied PRs was in the condensed chromatin. After occupation of PRs with progesterone (P), decondensation or dispersion of chromatin was observed. At the same time, the labelling in the border area of condensed and dispersed chromatin, and in the dispersed chromatin, increased. The changes were statistically significant. The results can be explained by conformational changes of the PR-containing chromatin rather than by translocation of PRs from one site to another.  相似文献   

13.
在2009-2010和2010-2011年小麦生长季,设置10、20、40、60、80和100 m 6个畦田长度,研究不同畦长对小麦耗水特性及产量的影响.结果表明: ≤80 m畦长处理下,随畦长的增加,灌水量逐渐增加,灌水量占总耗水量的比例增加,土壤贮水消耗量减少,小麦拔节至开花期的耗水量和生长季总耗水量均减少,开花期0~200 cm各土层土壤含水量增加,土壤供水能力提高,籽粒产量和水分利用效率逐渐提高.与80 m畦长处理相比,<80 m畦长处理的灌水量少,上层土壤含水量低,促使小麦吸收更多的深层贮水,总耗水量增加,不利于节水;而100 m畦长处理的灌水量、土壤贮水消耗量和总耗水量均增加,由于一次性灌水量过多且灌溉水分布不均匀,导致小麦千粒重降低,籽粒产量和水分利用效率显著下降,也不利于节水高产.  相似文献   

14.
不同降雨条件下坡长对喀斯特坡面土壤侵蚀的影响   总被引:3,自引:0,他引:3  
基于2012-2014年对贵州省石桥小流域布设的5个坡长(5、10、15、20、25 m)径流小区的59次侵蚀性降雨条件下的产流产沙数据,分析不同降雨条件下喀斯特裸坡产流产沙与坡长的关系.结果表明:研究区坡面产流量随坡长的增加总体呈先减少后增加再减少的趋势,产沙量随坡长的增加先上升后下降.研究区59次侵蚀性降雨按降雨量...  相似文献   

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