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991.
The disaccharide trehalose is a key element involved in anhydrobiosis (the capability of surviving almost complete dehydration) in many organisms. Its presence also confers resistance to desiccation and high osmolarity in bacterial and human cells by protecting proteins and membranes from denaturation. The present study used a novel murine dry eye model induced by controlled low-humidity air velocity to determine whether topically applied trehalose could heal ocular surface epithelial disorders caused by ocular surface desiccation. In addition, the efficacy of 87.6 mM trehalose eyedrops was compared with that of 20% serum, the efficacy of which has been well documented. Mice ocular surface epithelial disorders were induced by exposure of murine eyes to continuous controlled low-humidity air velocity in an intelligently controlled environmental system (ICES) for 21 days, which accelerated the tear evaporation. The mice were then randomized into three groups: the control group received PBS (0.01M) treatment; a second group received 87.6 mM trehalose eyedrops treatment; and the third group received mice serum eyedrops treatment. Each treatment was administered as a 10 μl dose every 6 h for 14 days. The resultant changes in corneal barrier function and histopathologic examination of cornea and conjunctiva were analyzed and the level of apoptosis on the ocular surface was assessed using active caspase-3. After 14 days of treatment, the corneal fluorescein staining area, the ruffling and desquamating cells on the apical corneal epithelium, as well as the apoptotic cells on ocular surface epithelium had significantly reduced in eyes treated with trehalose compared with those treated with serum and PBS. In contrast, after 14 days of treatment, improvements in the thickness of the corneal epithelium, the squamous metaplasia in conjunctival epithelium and the number of goblet cells of the conjunctiva were less marked in eyes treated with trehalose compared with serum. These results demonstrated that trehalose could improve the appearance of ocular surface epithelial disorders due to desiccation through suppression of apoptosis. Trehalose produces some of the same responses as serum upon topical application and can maintain corneal health. 相似文献
992.
Shaoyi Chen Coleen M Atkins Chunli L Liu Ofelia F Alonso W Dalton Dietrich Bingren R Hu 《Journal of cerebral blood flow and metabolism》2007,27(5):939-949
In response to traumatic brain injury (TBI), neurons initiate neuroplastic processes through the activation of intracellular signaling pathways. However, the molecular mechanisms underlying neuroplasticity after TBI are poorly understood. To study this, we utilized the fluid-percussion brain injury (FPI) model to investigate alterations in the mammalian target of rapamycin (mTOR) signaling pathways in response to TBI. Mammalian target of rapamycin stimulates mRNA translation through phosphorylation of eukaryotic initiation factor 4E binding protein-1 (4E-BP1), p70 ribosomal S6 kinase (p70S6K), and ribosomal protein S6 (rpS6). These pathways coordinate cell growth and neuroplasticity via dendritic protein synthesis. Rats received sham surgery or moderate parasagittal FPI on the right side of the parietal cortex, followed by 15 mins, 30 mins, 4 h, 24 h, or 72 h of recovery. Using Western blot analysis, we found that mTOR, p70S6K, rpS6, and 4E-BP1 phosphorylation levels were significantly increased in the ipsilateral parietal cortex and hippocampus from 30 mins to 24 h after TBI, whereas total protein levels were unchanged. Using confocal microscopy to localize these changes, we found that rpS6 phosphorylation was increased in the parietal cortex and all subregions of the hippocampus. In accordance with these results, eIF4E, a key, rate-limiting mRNA translation factor, was also phosphorylated by mitogen-activated protein kinase-interacting kinase 1 (Mnk1) 15 mins after TBI. Together, these results suggest that changes in mRNA translation may be one mechanism that neurons use to respond to trauma and may contribute to the neuroplastic changes observed after TBI. 相似文献
993.
目的 探讨磁共振成像各种方法对脑静脉畸形的诊断价值。方法 收集本院6例脑静脉畸形病例,均进行过磁共振T1WI、T2WI扫描,其中部分病例做过DWI、T2FLAIR、MRA、MRV、T1WI增强扫描及DSA。结果 幕上4例,幕下2例,T1WI、T2WI表现:引流静脉均为流空的低信号,深髓静脉为细条状长T1、长T2信号。其中1例DWI引流静脉及深髓静脉区域低信号;1例T2 FLAIR引流静脉流空的低信号,深髓静脉高信号;2例MRA均阴性,但MRV显示深髓静脉汇入引流静脉;2例T1 WI增强扫描:深髓静脉呈轮辐状汇入引流静脉;1例DSA:动脉期阴性,静脉期见典型的“海蛇头”征。结论 磁共振能明确诊断脑静脉畸形,T1WI增强扫描及MRV均较敏感,DSA为诊断脑静脉畸形金标准。 相似文献
994.
目的 探讨经尿道前列腺汽化电切术(transurethral electrovaporization of the prostate,TUVP)电切深度标识的可行性。方法 回顾性分析616例前列腺增生症临床资料,其中310例术前彩超提示合并前列腺钙化,156例合并膀胱结石,23例合并膀胱肿瘤。TUVP操作过程中,观察到合并前列腺结石和机械操作“打滑现象”,停止电切。结果 全组手术时间30~120min,平均75min。术中验证术前彩超提示合并前列腺钙化的310例前列腺钙化为结石,同时发现其余306例均存在结石。1例术中膀胱穿孔,无尿道直肠瘘和尿道电切综合征发生。325例随访3~6个月,平均4.5月,最大尿流率由6.5~8.5ml/s提高到18~22ml/s,残余尿由70~150ml降至0~10ml,国际前列腺症状评分由19~24.5分降至0~7分。138例膀胱结石和23例膀胱肿瘤无复发。结论 前列腺结石和机械操作“打滑现象”作为TUVP的电切深度标识是切实可行的。 相似文献
995.
改良犬原位背驮式肝移植的解剖学观察 总被引:1,自引:0,他引:1
目的观察犬肝脏解剖学特点,探索建立改良的犬同种异体原位背驮式肝移植模型。方法对15只杂交犬的肝脏进行活体和尸体标本的解剖观察。结果犬肝共分7叶,门静脉分左右支进入肝脏,门静脉左支供应约70%肝组织(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ叶),门静脉右支供应约30%肝组织(Ⅵ、Ⅶ叶),分别阻断门静脉左、右支后5 min左右门静脉压力达到峰值,并迅速回复至门静脉正常压力值上限范围内;肝动脉和胆管与门静脉分支伴行进入各肝叶;左肝静脉粗大,可以作为肝静脉重建的流出道,其余3~6支肝静脉可以分别结扎,肝后下腔静脉易于与肝脏分离。结论犬肝的解剖学特点适宜于建立改良的原位背驮式肝移植模型。 相似文献
996.
Lester M. Arguelles Xiaobin Wang Binyan Wang Hakan Demirtas Jianhua Yang Zhiping Li Liuliu Wang Xue Liu Genfu Tang Houxun Xing Xiping Xu 《Archives of osteoporosis》2007,2(1-2):7-20
Introduction This report examines the relationship of body mass index (BMI), percent body fat (%BF), and bone mass in a cohort of male
and female twins recruited from Anhui province, China, ages 6–18 years—577 male pairs (mean age = 11.4) and 478 female pairs
(mean age = 11.6).
Methods Whole body bone mineral content (WBMC) in (g), whole body bone area (WBA) in (cm2), and %BF were measured using DEXA (Lunar Prodigy, USA). Regression analysis of within-pair differences was used to assess
the strength of the association, and the analysis was stratified by gender and age group, where age cut-offs were based on
ages at spermarche or menarche estimated from large population based studies in China. Males were stratified at ages before
14 and age 14–18, and females at ages prior to 12 and age 12–18.
Results Univariately, BMI and %BF were associated with WBMC and WBA in the younger males and females, and in older males; %BF was
significant only in older females. Multivariate models included both BMI and %BF. Among the younger males, age < 14, BMI and
%BF were significantly associated with WBMC and WBA. In the younger females, age < 12, %BF was only significant to WBA. In
the older age group, only BMI was significant to WBMC and WBA in females, but in males, BMI was positively associated, and
%BF was negatively associated with both bone measures.
Discussion These findings show that association between BMI and %BF and bone mass differ across gender and developmental stages, and
%BF appears to be beneficial at younger ages, but detrimental or non-beneficial at older ages of development. 相似文献
997.
998.
Hongning Zhao Xiaoming Wang Junqiang Zhang Deben Yang Xiaoqiong Zhao Xin Liu Hui Huang Jianxiu Hu 《中国神经再生研究》2007,2(11):675-677
BACKGROUND: The examination of sympathetic skin response is an important index for assessing the autonomic nerve function, and patients with myasthenia gravis are always accompanied by dysautonomia. Therefore, it will be important to know whether sympathetic skin response can be used as the index for the clinical evaluation of myasthenia gravis.
OBJECTIVE: To investigate the diagnostic value of sympathetic skin response in the damage of autonomic nerve function of patients with myasthenia gravis.
DESIGN: A case-controlled comparative observation.
SETTING: Department of Neurology and Room of Nerve Electromyogram, the Affiliated Hospital of North Sichuan Medical College.
PARTICIPANTS: Thirty outpatients or inpatients with myasthenia gravis were selected from the Department of Neurology, the Affiliated Hospital of North Sichuan Medical College from May 2006 to May 2007, including 9 males and 21 females, aged 8–72 years with a mean age of (28±5) years old. They were all accorded with the diagnostic standards of myasthenia gravis, accompanied by different severity of autonomic nerve symptoms, including poor skin nutrition, sweating of hands and feet, pyknocardia, persistent hypotension, abdominal pain, constipation, etc. They all had not taken any drug affecting the autonomic nerve function before the examination. Informed consents were obtained from all the patients. Meanwhile, 30 healthy physical examinees were enrolled as the normal control group, including 10 males and 20 females, aged 10–75 years with a mean age of (31±5) years old. Approval was obtained from the hospital ethic committee.
METHODS: After admission, the patients were examined with sympathetic skin response using DANTEC keypoint 2.0 electromyography evoked potential apparatus (Danmark). The changes of the latency and wave amplitude of sympathetic skin response were observed. The subjects in the normal control group were examined with the same methods at physical examination. Abnormality was judged by the disappearance of wave form, latency longer than that in the normal control group by Mean±2.5SD, or wave amplitude lower than the average value in the normal control group by 50%.
MAIN OUTCOME MEASURES: The results of the latency and wave amplitude of sympathetic skin response were compared between the patients with myasthenia gravis and normal controls.
RESULTS: All the 30 patients with myasthenia gravis and 30 healthy physical examinees were involved in the final analysis of results. There were no significant differences between the left and right upper and lower limbs in both the myasthenia gravis group and normal control group (P > 0.05). In the myasthenia gravis group, the abnormal rate of sympathetic skin response was 37% (11/30), the latency was prolonged and the wave amplitude was decreased as compared with those in the normal control group, and there were significant differences (P < 0.01).
CONCLUSION: Sympathetic skin response can be used as an electrophysiological index for judging the damages of autonomic nerve function in patients with myasthenia gravis. 相似文献
999.
Complex segregation analyses of bone mineral density in Chinese 总被引:3,自引:1,他引:2
China has the largest population in the world; approximately 7% of the total population suffers from primary osteoporosis. Osteoporosis is mainly characterized by low bone mineral density (BMD). In the present study, familial correlation and segregation analyses for spine and hip BMDs have been undertaken for the first time in a Chinese sample composed of 401 nuclear families with a total of 1,260 individuals. The results indicate a major gene of additive inheritance for hip BMD, whereas there is no evidence of a major gene influencing spine BMD. Significant familial residual effects are found for both traits, and heritability estimates (±SE) for spine and hip BMDs are 0.807(0.099) and 0.897(0.101), respectively. Sex and age differences in genotype‐specific average BMD are also observed. This study provides the first evidence quantifying the high degree of genetic determination of BMD variation in the Chinese. 相似文献
1000.
电视硬质气管镜治疗大气道良性肿瘤 总被引:4,自引:4,他引:0
目的探讨电视硬质气管镜在大气道良性肿瘤治疗中的价值.方法2002年9月~2005年4月,我院应用电视硬质气管镜治疗大气道良性肿瘤7例,其中气管1例,隆突1例,左主支气管3例,右主支气管2例.手术采用静脉全身麻醉,喷射通气供氧,探查评估气道后,首先冷冻或电凝肿瘤,破坏肿瘤血供,再以活检钳分块取出,蒂部采用冷冻或氩气凝固处理;对于宽蒂肿瘤,内镜下将肿瘤主体清除后中转开胸行气管局部切除吻合术.结果7例手术均顺利,无一例死亡和严重并发症发生.6例气管窄蒂良性肿瘤镜下完整摘除,1例气管膜部宽蒂平滑肌瘤先内镜清除肿瘤主体后中转开胸行气管局部切除.术后病理为错构瘤2例,平滑肌瘤3例,嗜酸性肉芽肿性腺瘤1例,炎症组织1例.7例随访3~36个月,平均17.3月,无肿瘤复发.结论电视硬质气管镜治疗大气道良性肿瘤安全可靠. 相似文献