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11.

Purpose

The current study was undertaken to investigate whether glaucoma affects the sleep quality and whether there is any difference between patients with primary glaucoma (primary open angle glaucoma, POAG and primary angle-closure glaucoma, PACG) and healthy subjects, using a validated self-rated questionnaire, the Pittsburgh Sleep Quality Index (PSQI).

Methods

The sleep quality of patients with POAG and PACG was tested against normal controls. Subjects were divided into three sub-groups according to age. Differences in the frequency of sleep disturbances (PSQI score >7) were assessed. The differences of sleep quality within the three groups and within the POAG group depending on the patients’ intraocular pressure (IOP) and impairment of visual field (VF) were also studied.

Results

92 POAG patients, 48 PACG patients and 199 controls were included. Sleep quality declined with age in control and POAG group (tendency chi-square, P<0.05). The prevalence of sleep disturbances was higher in POAG and PACG group than in the control group, the differences were statistically significant. The prevalence of sleep disturbances was higher in patients with PACG, compared to POAG patients in the age interval of 61–80. In POAG group, the ratio of patients with sleep disorders increased with augmented impairment of VF, but the differences were not statistically significant (χ2-test, P>0.05). No significant differences were found in POAG group between patients with a highest IOP in daytime and at nighttime (χ2-test, P>0.05).

Conclusions

The prevalence of sleep disorders was higher in patients with POAG and PACG than in controls. PACG patients seemed to have a more serious problem of sleep disorders than POAG patients between 61 to 80 years old. No correlation was found between the prevalence of sleep disorders and impairment of VF or the time when POAG patients showed a highest IOP.  相似文献   
12.

Purpose

To explore ocular changes in healthy people after exercise.

Methods

Twenty five volunteers underwent exercise for 15 minutes on a treadmill. Measurements of choroidal thickness, intraocular pressure (IOP), ocular biometry, and blood pressure were taken before and after exercise. Enhanced Depth Imaging optical coherence tomography (EDI-OCT) was used to measure choroidal thickness at the fovea. Intraocular pressure (IOP) was measured by Goldmann applanation tonometry. Ocular biometric measures were collected using A scan ultrasound. Blood pressure was measured concurrently with the acquisition of the scans.

Results

Twenty five volunteers (25 eyes) with a mean age of 25.44±3.25 years were measured. There was a significant increase in systolic and diastolic pressure after exercise (P<0.05). The IOP showed a significant decrease after exercise (P<0.05). However there was no significant difference in the mean choroidal thickness, ocular axial length, anterior chamber depth, lens thickness, or vitreous length before and after exercise measurements (P>0.05).

Conclusion

There was a significant decrease in IOP from exercise without a change in choroidal thickness and ocular biometric measures. IOP and choroidal thickness were not correlated, suggesting that the IOP decrease from exercise is not due to changes in choridal thickness.  相似文献   
13.
通过测定亚热带马尾松和杉木树干韧皮部水溶性糖δ13C值的连日变化,及其对天气变化过程的响应,研究δ13C值对短期天气变化动态的响应特征。结果显示,春季马尾松和杉木树干韧皮部水溶性糖δ13C日均值分别介于-26.81‰到-26.49‰之间,以及-29.26‰到-27.47‰之间,平均值分别为(-26.58±0.12)‰和(-28.67±0.65)‰。进一步分析表明,马尾松树干韧皮部水溶性糖δ13C值与取样之前第4天的太阳辐射、水气压亏缺、相对湿度和空气温度显著相关(P≤0.05),杉木树干韧皮部水溶性糖δ13C值取样之前第3天的太阳辐射、水气压亏缺和相对湿度显著相关(P≤0.05),但与空气温度的相关性不显著(P≤0.05)。在所测定的环境因子中,太阳辐射是影响马尾松和杉木树干韧皮部水溶性糖δ13C值的首要因素。当天降水事件可能导致马尾松和杉木树干韧皮部水溶性糖δ13C值连日变化出现异常波动。马尾松和杉木韧皮部水溶性糖δ13C值可以敏感记录短期天气变化动态。  相似文献   
14.
福建长汀重建植被马尾松与木荷光合特性比较   总被引:5,自引:0,他引:5  
黄儒珠  李机密  郑怀舟  王健  周延锋 《生态学报》2009,29(11):6120-6130
比较了福建长汀水土流失区重建植被措施治理后,2个不同恢复程度生境中的马尾松(Pinus massoniana)与木荷(Schima superba)光合特性季节变化及日进程,结果表明:(1)马尾松净光合速率(Pn)具有明显的季节变化特征,其中恢复程度较低生境(样地Ⅰ)马尾松Pn最大值出现在秋季,恢复程度较高生境(样地Ⅱ)马尾松Pn春季最大,秋季次之;样地Ⅱ马尾松Pn日均值冬季显著低于样地Ⅰ(P<0.05),春季极显著高于样地Ⅰ(P<0.01),反映出样地Ⅱ马尾松抵御低温胁迫的能力强于样地Ⅰ马尾松.(2)样地Ⅰ和样地Ⅱ木荷Pn季节变化趋势一致,最大值均出现在夏季,且样地Ⅱ木荷Pn高于样地Ⅰ;此外,样地Ⅱ木荷Pn秋季仍维持在较高水平.说明重建植被措施治理后,木荷在恢复程度较高生境中生长良好.(3)根据气孔导度、胞间CO2浓度和气孔限制值的变化方向判断,夏季和秋季样地Ⅰ马尾松与木荷Pn主要受气孔因素影响,8:00后呈缓慢下降趋势,显示在长期较为恶劣的生境条件下,马尾松与木荷已形成一种趋同的生理生态适应机制,即通过气孔调节限制蒸腾失水,但这种适应是以降低光合速率为代价的,这也是样地Ⅰ马尾松与木荷生长缓慢的一个重要原因.(4)同一生境,木荷Pn与蒸腾速率(Tr)均明显高于马尾松,尤其样地Ⅱ2树种间的差异更显著,表明重建植被措施实施后,生态恢复程度较高生境中,木荷生长、竞争优势强于马尾松.  相似文献   
15.

Key message

Compared with annual tree-ring cellulose δ 18 O, intra-annual cellulose δ 18 O has potential to reconstruct precipitation with higher resolution and stronger signal intensity.

Abstract

Annual tree-ring cellulose oxygen isotope values (δ18O) of Fokienia hodginsii provide a promising proxy of monsoon-season precipitation in Southeast China. Measuring intra-annual cellulose δ18O values may reveal the seasonal variability of precipitation and the associated climate influences. Here, we examine intra-annual variation of cellulose δ18O values in Fokienia hodginsii and Cryptomeria fortune from Fujian Province, Southeast China. Both species exhibited considerable intra-annual variations in cellulose δ18O (range ~6 ‰) with a consistent pattern of enriched values near the annual ring boundary and depleted values in the central portion of the ring. Seasonal patterns in the tree-ring δ18O values generally followed changes in precipitation δ18O values. Compared with annual tree-ring cellulose δ18O, intra-annual cellulose δ18O has potential to reconstruct precipitation with higher resolution and stronger signal intensity. July tree-ring cellulose δ18O is significantly correlated (r = ?0.58, p < 0.05) with July precipitation, and June–August tree-ring cellulose δ18O and annual tree-ring cellulose δ18O, respectively, explain 52 and 41 % of the actual variance of April–August precipitation. In addition, May–October cellulose δ18O values during El Niño years are higher than in La Niña years, and April to October rainfall is lower in El Niño years than in La Niña years. Combining the significant correlations between inter-annual cellulose δ18O values and sea surface temperatures in the central tropical Pacific, our results support the hypothesis that El Niño–Southern Oscillation affects tree-ring cellulose δ18O in Southeast China by modulating seasonal precipitation.
  相似文献   
16.
In this study, hypoproliferation and defects of effectors and cytokines in CD4+ and CD8+ T-cells via ICOS costimulation were found in active SLE patients, relative to normal individuals and RA patient controls. Exogenous IL-2 can partially reverse those defects. In addition, low level of ERK phosphorylation in ICOS-mediated signaling pathway was discovered in lupus CD4+ and CD8+ T-cells. When blocked with ERK-specific chemical inhibitor PD98059, cell proliferation and IL-2 production via ICOS costimulation from both CD4+ and CD8+ T-cells will be severely inhibited. These findings confirmed the dysfunction of both CD4+ and CD8+ T-cells after ICOS costimulation in lupus patients and most importantly pointed out that impairment of ERK activation might be one of the critical factors involved in ICOS-mediated IL-2 and T-cell hypoproliferation in active SLE.  相似文献   
17.
18.
基于资源等价分析法的海洋溢油生物资源损害评估   总被引:1,自引:0,他引:1  
李京梅  侯怀洲  姚海燕  王晓玲 《生态学报》2014,34(13):3762-3770
评估海洋溢油造成的生物资源损害,对我国目前迫切需要制定的海洋生态补偿政策以及生态修复计划具有重要的现实意义。针对我国2011年渤海蓬莱19-3油田溢油事故,评估生物资源受损程度,利用资源等价分析法计算修复工程规模。结果表明,底栖生物和非底栖生物(包括浮游幼虫幼体、鱼卵、仔稚鱼等)的受损程度分别为30%和71.4%,受损面积分别为1600 km2和6400 km2。若以修建海洋生态保护区作为补偿修复工程,在修复期为20 a、贴现率为3%条件下,修复工程规模应为1059km2,才能补偿溢油造成的底栖和非底栖生物资源损失。其结论可以作为海洋管理部门进行溢油生物资源损害评估和生态修复管理的技术依据。  相似文献   
19.

Background and Purpose

Wilson’s disease (WD), also known as hepatoleticular degeneration (HLD), is a rare autosomal recessive genetic disorder of copper metabolism, which causes copper to accumulate in body tissues. In this study, rats fed with copper-laden diet are used to render the clinical manifestations of WD, and their copper toxicity-induced organ lesions are studied. To investigate metabolic behaviors of ‘decoppering’ process, penicillamine (PA) was used for treating copper-laden rats as this chelating agent could eliminate excess copper through the urine. To date, there has been limited metabolomics study on WD, while metabolic impacts of copper accumulation and PA administration have yet to be established.

Materials and Methods

A combination of 1HNMR spectroscopy and multivariate statistical analysis was applied to examine the metabolic profiles of the urine and blood serum samples collected from the copper-laden rat model of WD with PA treatment.

Results

Copper accumulation in the copper-laden rats is associated with increased lactate, creatinine, valine and leucine, as well as decreased levels of glucose and taurine in the blood serum. There were also significant changes in p-hydroxyphenylacetate (p-HPA), creatinine, alpha-ketoglutarate (α-KG), dimethylamine, N-acetylglutamate (NAG), N-acetylglycoprotein (NAC) in the urine of these rats. Notably, the changes in p-HPA, glucose, lactate, taurine, valine, leucine, and NAG were found reversed following PA treatment. Nevertheless, there were no changes for dimethylamine, α-KG, and NAC as a result of the treatment. Compared with the controls, the concentrations of hippurate, formate, alanine, and lactate were changed when PA was applied and this is probably due to its side effect. A tool named SMPDB (Small Molecule Pathway Database) is introduced to identify the metabolic pathway influenced by the copper-laden diet.

Conclusion

The study has shown the potential application of NMR-based metabolomic analysis in providing further insights into the molecular mechanism underlying disorder due to WD.  相似文献   
20.
To determine the interdependence of intracranial pressure (ICP) and intraocular pressure (IOP) and how it affects optic nerve pressures, eight normal dogs were examined using pressure-sensing probes implanted into the left ventricle, lumbar cistern, optic nerve subarachnoid space in the left eye, and anterior chamber in the left eye. This allowed ICP, lumbar cistern pressure (LCP), optic nerve subarachnoid space pressure (ONSP) and IOP to be simultaneously recorded. After establishing baseline pressure levels, pressure changes that resulted from lowering ICP (via shunting cerebrospinal fluid (CSF) from the ventricle) were recorded. At baseline, all examined pressures were different (ICP<LCP<ONSP), but correlated (P>0.001). As ICP was lowered during CSF shunting, IOP also dropped in a parallel time course so that the trans-lamina cribrosa gradient (TLPG) remained stable (ICP-IOP dependent zone). However, once ICP fell below a critical breakpoint, ICP and IOP became uncoupled and TLPG changed as ICP declined (ICP-IOP independent zone). The optic nerve pressure gradient (ONPG) and trans-optic nerve pressure gradient (TOPG) increased linearly as ICP decreased through both the ICP-IOP dependent and independent zones. We conclude that ICP and IOP are coupled in a specific pressure range, but when ICP drops below a critical point, IOP and ICP become uncoupled and TLPG increases. When ICP drops, a rise in the ONPG and TOPG creates more pressure and reduces CSF flow around the optic nerve. This change may play a role in the development and progression of various ophthalmic and neurological diseases, including glaucoma.  相似文献   
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