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31.
谷氨酸脱羧酶抑制剂L-苹果酸对小鼠学习记忆的影响   总被引:5,自引:0,他引:5  
周红宇  郑国统  张士善 《药学学报》1996,31(12):897-900
跳台法和Y迷宫法试验表明,小鼠po L-苹果酸600mg·kg-1连续5d后对记忆的获得、巩固和再现均有明显的改善作用,并能促进空间辨别学习能力;L-苹果酸改善记忆的作用能被NMDA受体拮抗剂氯胺酮所拮抗。脑内游离氨基酸测定显示,L-苹果酸可明显降低小鼠脑内GABA水平,提高Glu/GABA比值。实验结果表明,脑内GABA水平下降,Glu/GABA比值升高对学习记忆有正性调节作用。  相似文献   
32.
The remarkable susceptibility of the inner ear of the patas monkey (Erythrocebus patas) to the ototoxic action of dihydrostreptomycin (DHSM) (and streptomycin (SM)) is well established in this paper and affords a rare example of a species-specific reaction to a restricted class of compounds within the aminoglycoside group of antibiotics. In a series of experiments, behavioral and morphological observations together provided the following profile of DHSM ototoxicity in the patas monkey: Sudden onset of hearing loss beginning after 7-9 weeks of treatment; Substantial, though often partial, hearing impairment beginning at the high frequencies and progressing with or without continued treatment to the low frequencies; In the inner ear, a corresponding and selective loss of nerve fibers and of outer hair cells, relative to inner hair cells, beginning in the base of the cochlea and proceeding toward the apex; Continued and progressive loss of hearing for several months after cessation of drug treatment; and Non-auditory effects in some animals on the kidney and vestibular system. Results from control experiments confirmed this special relationship between the patas monkey and DHSM: Other nonhuman primates (macaques and vervet monkeys) were essentially unaffected by DHSM; The patas showed no equivalent sensitivity to other aminoglycosides such as kanamycin or to other forms of ototraumatic insult such as intense noise.  相似文献   
33.
Infant visual acuities have been a difficult measurement to obtain for a number of reasons. This study evaluates the clinical usefulness of the Infant Vision Tester, a new preferential-looking instrument. Twenty-eight infants from age 2 months to 22 months were followed on a bi-monthly basis and their visual acuities were measured. It was found that the practicing optometrist can predict approximate visual acuities and progression of acuity improvement from one age group to another. A number of helpful suggestions for proper testing environment are also suggested by the investigator.  相似文献   
34.

Background  

Chromosome 22q11.2 deletion syndrome is one of the most common genetic causes of cognitive impairment and developmental disability yet little is known about the neural bases of those challenges. Here we expand upon our previous neurocognitive studies by specifically investigating the hypothesis that changes in neural connectivity relate to cognitive impairment in children with the disorder.  相似文献   
35.
Dopaminergic treatment in dementia with Lewy bodies (DLB) requires balancing risk of worsened psychosis and potential motor benefit. We assessed the effects of increased dopaminergic medication on psychosis and motor function in DLB. We studied 19 subjects fulfilling probable DLB Consensus criteria before and after increased dopaminergic medications. Standard clinical measures included: Thought Disorder score from the Unified Parkinson's disease Rating Scale (UPDRS) Part I, total motor score (UPDRS Part III), and Hoehn–Yahr (H&Y) stage. Motor benefit defined as >10% improvement over baseline UPDRS Part III score, occurred in only one‐third of subjects. In this group, worsened hallucinations or psychosis developed in one‐third. Considering motor benefit without exacerbation of psychosis as our aim, only 4 DLB subjects (22%) achieved this goal. Our results suggest that dopaminergic medications have limited benefit in DLB because of the low likelihood of motor improvement and the risk of psychosis exacerbation. © 2008 Movement Disorder Society  相似文献   
36.
Apathy is a common condition in Parkinson's disease (PD) and is generally defined as a lack of motivation. It is associated with more severe cognitive dysfunction and a decrease in activities of daily living (ADL) performance. Anhedonia, the inability to experience pleasure, can be a symptom of both depressive and apathetic syndromes. The Movement Disorder Society (MDS) commissioned a task force to assess the clinimetric properties of apathy and anhedonia scales in PD patients. A systematic literature review was conducted to identify scales that have either been validated or used in PD patients. Apathy scales identified for review include the Apathy Evaluation Scale (AES), the Apathy Scale (AS), the Apathy Inventory (AI), and the Lille Apathy Rating Scale (LARS). In addition, item 4 (motivation/initiative) of the Unified Parkinson's Disease Rating Scale (UPDRS) and item 7 (apathy) of the Neuropsychiatric Inventory (NPI) were included. Anhedonia scales identified for review were the Snaith‐Hamilton Pleasure Scale (SHAPS) and the Chapman scales for physical and social anhedonia. Only the AS is classified as “recommended” to assess apathy in PD. Although item 4 of the UPDRS also meets the criteria to be classified as recommended, it should be considered for screening only because of the obvious limitations of a single item construct. For the assessment of anhedonia, only the SHAPS meets the criteria of “Suggested.” Information on the validity of apathy and anhedonia scales is limited because of the lack of consensus on diagnostic criteria for these conditions. © 2008 Movement Disorder Society  相似文献   
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