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71.
72.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用.  相似文献   
73.
QuantitativerelationshipbetweenpupillaryreflexfeatureanditsdiopterinretinoscopyXuShang(徐上);JiShangnian(计尚年)(DepartmentofOphth...  相似文献   
74.
98例颅内肿瘤经手术和病理检查证实,其中36例脑瘤伴精神障碍,最常见的精神症状是情感淡漠,情感不稳,遗忘,意识模糊,嗜睡、痴呆。为最常见的部位为额顶部和颞叶部。  相似文献   
75.
PharmacokineticsofintravenouslyadministeredsodiumdichloroacetateinrabbitsGuBin(顾斌);SongLing(宋岭);JiangYongpei(蒋永培);WenAidong(文...  相似文献   
76.
We have previously shown that neuregulin-1 (NRG-1) protects neurons from ischemic brain injury if administered before focal stroke. Here, we examined the therapeutic window and functional recovery after NRG-1 treatment in rats subjected to 90 mins of middle cerebral artery occlusion (MCAO) and 24 h of reperfusion. Neuregulin-1 (2.5 ng/kg bolus, 1.25 ng/kg/min infusion) reduced infarct volume by 89.2%+/-41.9% (mean+/-s.d.; n=8; P<0.01) if administered immediately after the onset of reperfusion. Neuroprotection was also evident if NRG-1 was administered 4 h (66.4%+/-52.6%; n=7; P<0.01) and 12 h (57.0%+/-20.8%; n=8; P<0.01) after reperfusion. Neuregulin-1 administration also resulted in a significant improvement of functional neurologic outcome compared with vehicle-treated animals (32.1%+/-5.7%; n=9; P<0.01). The neuroprotective effect of the single administration of NRG-1 was seen as long as 2 weeks after treatment. Neurons labeled with the neurodegeneration marker dye Fluoro-JadeB were observed after MCAO in the cortex, but the numbers were significantly reduced after NRG-1 treatment. These results indicate that NRG-1 is a potent neuroprotective compound with an extended therapeutic window that has practical therapeutic potential in treating individuals after ischemic brain injury.  相似文献   
77.
Influence of lecithin on mitochondrial DNA and age-related hearing loss.   总被引:3,自引:0,他引:3  
OBJECTIVES: Lecithin is a polyunsaturated phosphatidylcholine (PPC), which are high energy functional and structural elements of all biologic membranes. PPC play a rate-limiting role in the activation of numerous membrane-located enzymes, including superoxide dismutase and glutathione, which are important antioxidants protecting cell membranes from damage by reactive oxygen species (ROS). ROS-induced damage to mitochondrial DNA may lead to reduced mitochondrial function in the cochlea and resultant hearing loss. STUDY DESIGN AND SETTING: The effects of lecithin on aging and age-associated hearing loss were studied in rats by measuring hearing sensitivities using auditory brainstem responses (ABR). In addition, mitochondrial function as a measure of aging was assessed by determining mitochondrial membrane potentials using flow cytometry and by amplifying mitochondrial DNA deletions associated with aging. Harlan-Fischer rats aged 18 to 20 months (n = 14) were divided into 2 groups. The experimental group was supplemented orally for 6 months with lecithin, a purified extract of soybean phospholipid (Nutritional Therapeutics, Allendale, NJ). RESULTS: The data obtained were compared with the control group. ABRs were recorded at 2-month intervals and showed significant preservation of hearing sensitivities in the treated subjects. Flow cytometry revealed significantly higher mitochondrial membrane potentials in the treated subjects, suggesting preserved mitochondrial function. Finally, the common aging mitochondrial DNA deletion (mtDNA(4834)) were amplified from brain and cochlear tissue including stria vascularis and auditory nerve. This specific deletion was found significantly less frequent in all tissues in the treated group compared with the controls. CONCLUSION: These experiments support our hypothesis and provide evidence that lecithin may preserve cochlear mitochondrial function and protect hearing loss associated with aging.  相似文献   
78.
病理性近视眼的研究进展   总被引:5,自引:4,他引:1  
通过复习近年来相关文献,对近视眼发生发展机制与形觉剥夺之间的关系进行综合评述。认为近视眼的发生及眼轴延长与形觉剥夺有一定关系,深入研究其相关机制,对近视眼的早期防治具有重要意义。  相似文献   
79.
内脏高敏感与功能性胃肠病   总被引:3,自引:0,他引:3  
功能性胃肠病(functional gastrointestinal disorders,FGIDs)是指一组以慢性或反复发作的消化道症状就诊,但无明确胃肠黏膜结构改变或生化异常可查的症候群。心理、社会因素可加重FGIDs患者症状,患者可同时伴有躯体症状[1]。其发病机制目前尚不明确,最初该类疾病被认为是胃肠神经官能症,大量的流行病学资料表明,尽管精神压力与患者症状发作有关,但主要还是决定于患者的就医行为。此后,FGIDs发病机制的研究又集中在胃肠动力改变方面,肠易激综合征患者(IBS)、功能性消化不良患者(FD)、非心源性胸痛患者(NCCP)均发现了各种胃肠动力异…  相似文献   
80.
S D Xu 《中华外科杂志》1990,28(10):588-91, 636
108 pigs were shot at the level of lumbar 1 to investigate the changes of spinal cord in relation to the speed of shooting and the trajectory through which the bullet passed. The cord lesions of the specimens could be divided, according to its severity, into 4 grades: (1) transection in 41; (2) complete destruction in 43; both lesion 1&2 resulted in permanent paraplegia; (3) incomplete destruction in 13, those resulted in incomplete paraplegia eventually recovered; (4) mild damage, that was concussion in 11, resumed perfectly. Through a transducer sealed into the spinal canal, the intracanal pressure was recorded: (1) Shooting through spinal canal with a pressure over 5 kg caused cord transection. (2) shooting through canal wall with a pressure of 2.5 to 5; 0 kg caused complete cord destruction. (3) shooting nearby the outer margin of vertebra with a pressure less than 1.0 kg caused mild cord damage. It was found that the speed of bullet, the trajectory with relation to cord and the grade of cord lesion are in agreement with each other. The mutual effects among them would make one think it reasonable to classify cord injury as follows: 1. Injury from bullet through spinal canal or vertebral body usually causes cord transaction; 2. Injury from bullet through canal wall at high speed would make a chance of complete destruction in 94%; at low speed, a chance of either complete or incomplete lesion in 50% each. 3. Injury nearby vertebra, high speed bullet would cause a chance of complete cord lesion in 86%; low speed one would make a chance of incomplete lesion in 1/3 and mild lesion in 2/3.  相似文献   
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