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991.
The accuracy of metabolite concentrations measured using in vivo proton (1H) MRS is enhanced following correction for spin–spin (T2) relaxation effects. In addition, metabolite proton T2 relaxation times provide unique information regarding cellular environment and molecular mobility. Echo‐time (TE) averaging 1H MRS involves the collection and averaging of multiple TE steps, which greatly simplifies resulting spectra due to the attenuation of spin‐coupled and macromolecule resonances. Given the simplified spectral appearance and inherent metabolite T2 relaxation information, the aim of the present proof‐of‐concept study was to develop a novel data processing scheme to estimate metabolite T2 relaxation times from TE‐averaged 1H MRS data. Spectral simulations are used to validate the proposed TE‐averaging methods for estimating methyl proton T2 relaxation times for N‐acetyl aspartate, total creatine, and choline‐containing compounds. The utility of the technique and its reproducibility are demonstrated using data obtained in vivo from the posterior‐occipital cortex of 10 healthy control subjects. Compared with standard methods, distinct advantages of this approach include built‐in macromolecule resonance attenuation, in vivo T2 estimates closer to reported values when maximum TE ≈ T2, and the potential for T2 calculation of metabolite resonances otherwise inseparable in standard 1H MRS spectra recorded in vivo. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
992.
目的 观察菊花总黄酮在体外条件下对泪腺上皮细胞中雄激素受体(Androgen Receptor,AR)的调控作用及对下游的核因子κB(Nuclear Factor kappa B,NF-κB)、转化生长因子-β1(transforming growth factor-beta1,TGF-β1)的表达影响。方法 以过氧化氢(H2O2)诱导泪腺上皮细胞凋亡,建立细胞模型,设立无雄激素培养空白对照组、含雄激素培养对照组、无雄激素培养黄酮治疗组。以MTT法摸索含药血清最佳干预加入量;免疫印迹实验(Western Blot)以及实时荧光定量PCR法(Quantitative Real-Time PCR,qPCR)检测泪腺上皮细胞中AR、NF-κB及TGF-β1的表达情况;并应用雄激素受体阻断剂氟他胺进行AR阻断后再次检测上述指标 。结果 MTT法检测后计算得出含药血清干预细胞的最终浓度为13.2%;无雄激素培养黄酮治疗组及含雄激素培养对照组中AR、NF-κB及TGF-β1的表达增强,与空白对照组对比有显著差异(P<0.01);无雄激素培养黄酮治疗组中NF-κB表达量比含雄激素培养对照组表达量低,两者间的差异有统计学意义。氟他胺及含药血清干预后,无雄激素培养黄酮治疗组及含雄激素培养对照组中AR及NF-κB的表达未见提高,无统计学意义。结论 菊花总黄酮对泪腺上皮细胞可能存在拟雄激素效应,从而使AR、NF-κB表达增加,并通过上调TGF-β1的表达,可能起到在泪腺局部的抗炎作用。  相似文献   
993.
994.
针对厨余垃圾特点,设计节水、能耗低、能有效控制异味扩散的餐厨垃圾破碎-真空管道输送系统,并对不同输送方式进行优化研究。  相似文献   
995.
Purpose: RNA helicase p68 plays an important role in organ development and maturation through tuning cell proliferation. However, the character and role of p68 in the whole wound healing process need more study. Methods: First, we characterize expression of p68 in normal rat skin development postnatal. Then, we assayed dynamic change of p68 in rat skin from different stage after injury, and explored the role of p68 in proliferation and migration of three types of wound healing related cells. Results: p68 was down-regulated during skin developmental and maturation process, up-regulated after wound, peaked on day 14 and then significantly decreased. Wound fluid enhanced wound healing related cell proliferation and up-regulated expression of p68. Conversely, reducing p68 expression by RNA interference resulted in significantly slower proliferation and migration. Conclusion: Our results define an important role of RNA helicase p68 in skin wound healing process.  相似文献   
996.
焦虑是帕金森病(PD)患者常见的非运动症状之一,严重影响PD患者的生活质量,给家庭和社会带来很大的负担。但在临床工作中,PD患者的焦虑情绪并未引起足够重视,更难做到正确诊断和治疗。本文从PD患者焦虑的发生机制、临床特征、危险因素、诊断及其治疗进行综述,为PD患者焦虑的诊治提供参考。  相似文献   
997.
Melatonin has demonstrated a potential protective effect in central nervous system. Thus, it is interesting to determine whether pre‐ischemia melatonin administration could protect against cerebral ischemia/reperfusion (IR)‐related injury and the underlying molecular mechanisms. In this study, we revealed that IR injury significantly activated endoplasmic reticulum (ER) stress and autophagy in a middle cerebral artery occlusion mouse model. Pre‐ischemia melatonin treatment was able to attenuate IR‐induced ER stress and autophagy. In addition, with tandem RFP‐GFP‐LC3 adeno‐associated virus, we demonstrated pre‐ischemic melatonin significantly alleviated IR‐induced autophagic flux. Furthermore, we showed that IR induced neuronal apoptosis through ER stress related signalings. Moreover, IR‐induced autophagy was significantly blocked by ER stress inhibitor (4‐PBA), as well as ER‐related signaling inhibitors (PERK inhibitor, GSK; IRE1 inhibitor, 3,5‐dibromosalicylaldehyde). Finally, we revealed that melatonin significantly alleviated cerebral infarction, brain edema, neuronal apoptosis, and neurological deficiency, which were remarkably abolished by tunicamycin (ER stress activator) and rapamycin (autophagy activator), respectively. In summary, our study provides strong evidence that pre‐ischemia melatonin administration significantly protects against cerebral IR injury through inhibiting ER stress‐dependent autophagy. Our findings shed light on the novel preventive and therapeutic strategy of daily administration of melatonin, especially among the population with high risk of cerebral ischemic stroke.  相似文献   
998.
The effects of heat treatment on the antigenicity and potential allergenicity of α-Lactalbumin (α-LA), β-Lactoglobulin (β-LG), α-casein (α-CN), and β-casein (β-CN) in milk protein concentrates (MPCs) were investigated at temperatures in the range of 65–100°C for times from 10 to 30?min. The antigenicity and potential allergenicity of α-LA decreased significantly. The antigenicity of β-LG was sharply increased throughout the heat treatment, while the potential allergenicity decreased significantly only at 85°C and 100°C for 25?min. The antigenicity of α-CN and β-CN showed fluctuated changes, but were all lower than untreated sample. The α-CN potential allergenicity decreased when heated at 65°C and 70°C for 25?min. Compared with untreated sample, the potential allergenicity of β-CN increased sharply after heat treatment. The results showed that different proteins in the MPCs showed different sensitivities under heat treatment.  相似文献   
999.
目的 心肺复苏Utstein评价模式已被许多国家广泛用于心肺复苏评价研究.本文以心肺复苏结果Utstein评价模式设计心肺复苏注册登记表,以评价中国海南海南省人民医院心搏骤停患者流行病学特征、心肺复苏效果与影响因素.方法 应用心肺复苏Utstein模式注册登记表,对海南省人民医院急诊科511例心肺复苏患者进行前瞻性观察研究,评价本组患者心搏骤停流行病学特征及心肺复苏结果.结果 注册登记的511例心肺复苏患者纳入研究.本研究患者以40 ~ 70岁等年龄段心搏骤停发生率较高.既往史中,心血管系统疾病(190例,37.2%)、脑血管疾病(48例,9.4%)及呼吸系统疾病(39例,7.6%)等慢性疾病较为常见.173例(33.9%)为心源性心搏骤停,其中109例(21.3%)为急性心肌梗死.80例(15.7%)患者首次监测心律为心室纤颤.院内心搏骤停患者自主循环恢复率及成活出院率分别为47.0%和13.5%,院外心搏骤停患者为16.7%和4.7%.结论 本研究表明心血管系统疾病、脑血管疾病及呼吸系统疾病为最常见慢性疾病.急性心肌梗死、中风及创伤为最常见心搏骤停病因.院内心搏骤停组自主循环恢复率及成活出院率均高于院外心搏骤停组,两组差异具有统计学意义.  相似文献   
1000.
Background: Sun exposure can cause a range of skin disorders. Skin damage can be prevented by following certain sun‐protection measures. However, the majority of reported studies regarding sun‐exposure knowledge and behavior have involved Caucasian populations. Methods: A self‐administered multiple‐choice questionnaire was administered. The questionnaire consisted of 13 questions aimed at evaluating people's knowledge, awareness, and protection behavior regarding sun exposure, and their knowledge of sunscreens and sunscreen use. Results: A total of 623 volunteers were enrolled, including 238 men (38.2%) and 385 women (61.8%). The percentages of correct answers regarding sun‐exposure knowledge and awareness ranged from 50% to 80%. Overall, 58.8% used sunscreen as a sun‐protection measure in daily life, followed by use of protective clothes (49.3%), sun umbrella (45.4%), sunglasses (45.3%), and hat (42.2%). Fifty‐two percent thought that suntan was harmful or not attractive. The mean sun‐protection factor (SPF) of the sunscreens used was 27.7 ± 9.2 and the mean UVA protection grade (PA) was 2.3 ± 0.6. Conclusions: Knowledge and awareness concerning the harmful effects of sun exposure are widespread among the Chinese population. Sunscreens with high SPF and PA are the most commonly used among Chinese people. Clear sex differences were observed. There is a significant difference in the attitude toward suntan between Chinese and Caucasian populations.  相似文献   
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