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991.
Introduction - S-adenosyl-l-methionine (SAMe) is a naturally-occurring substance which is a major source of methyl groups in the brain. Material and methods - We conducted a meta-analysis of the studies on SAMe to assess the efficacy of this compound in the treatment of depression compared with placebo and standard tricyclic antidepressants. Results - Our meta-analysis showed a greater response rate with SAMe when compared with placebo, with a global effect size ranging from 17% to 38% depending on the definition of response, and an antidepressant effect comparable with that of standard tricyclic antidepressants. Conclusion - The efficacy of SAMein treating depressive syndromes and disorders is superior with that of placebo and comparable to that of standard tricyclic antidepressants. Since SAMe is a naturally occurring compound with relatively few side-effects, it is a potentially important treatment for depression.  相似文献   
992.
Mesial temporal sclerosis and volumetric investigations   总被引:2,自引:0,他引:2  
Volumetric MRI data acquisition permits reliable and accurate measurement of mesial temporal lobe structures. In normal subjects, these structures are very symmetric. A high degree of pathological specificity is associated with the finding of even minor volume asymmetries. Definition in this manner allows precise estimation of both absolute and relative volume differences, and precise anatomical localisation of volume loss within the hippocampus. There are good EEG and clinical correlates with the distribution of volume loss defined on MRI studies. Volumetric assessment is fast, reliable, non-invasive, and a relatively inexpensive component of the pre-operative work-up. It is the method of choice when imaging patients with clinical temporal lobe epilepsy undergoing pre-surgical evaluation. The finding of significant hippocampal volume asymmetry in a patient with clinical temporal lobe seizures being evaluated for epilepsy surgery may obviate the need for alternative sophisticated, invasive, or expensive investigative procedures. At our centre, such MRI allows "fast track" cases to proceed to surgery without further invasive investigations, and is likely to have a dramatic effect on pre-operative evaluation in most centres practising epilepsy surgery.  相似文献   
993.
At the Indiana University Medical Center, 99 patients with medically intractable complex partial seizures (MI-CPS) had presurgical evaluation with subsequent anterior temporal lobectomy. The majority of the patients had single photon emission tomography (SPECT) performed interictally as well as during an actual epileptic seizure (ictal scan). Decreased regional cerebral perfusion (rCP) was seen in 54/94 (57%) of the interictal scans corresponding to the eventual site of the surgery. However, ictal scans provided a higher yield; increased rCP in the temporal lobe during an actual seizure was observed in 60/82 (73%) concordant to the side of surgery. SPECT is a useful, noninvasive method of localizing the epilepti-form focus in patients with MI-CPS considered for resective surgery. Both interictal and ictal SPECT need to be performed; combined interictal hypo-perfusion and ictal hyperperfusion in the same focal area are unique to epileptogenic lesions. Ictal SPECT studies can be performed in the majority of patients during the period of continuous video/EEG monitoring with only a little additional effort. Combining the results of functional brain imaging (interictal and ictal SPECT, PET) with clinical semiology of seizures, surface and sphenoidal EEG, magnetic resonance imaging and other non-invasive tests, anterior temporal lobectomy can be recommended in approximately two-thirds of the patients without resorting to potentially dangerous intracranial EEG monitoring.  相似文献   
994.
A community-based case-finding sample of 1824 narcotic abusers in Stockholm County was used to standardize a set of rating scales in order to reflect levels of personality organization (PO), in the spirit of Kernberg's theory. PO is assumed to be a function of the ego's capacity to endure inner and outer stress, which manifests itself in the frequency and depth of regressions and the rate of recovery from them. The principles of a method, Rating Ego Balance, for charting the person's characteristic pattern of regression are presented, and its psychometric properties are described on the basis of item response theory. The scales have satisfactory reliabilities and maximal discrimination at subneurotic levels of PO. They show strong construct validity in relation to Kernberg's theory.  相似文献   
995.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
996.
12只大白鼠空腹灌注大剂量磁处理酒(实验组1、2); 另外18只大白鼠同等条件下灌注非磁处理酒(对照组1、2)及自来水(空白组),对比研究表明,血清胆固醇及清蛋白含量变化无显著差异(P>0.05),而血清葡萄糖含量实验组低于对照组,差异显著(P<0.05),提示,大剂量非磁处理酒可使血糖升高,而磁处理酒对血糖含量无显著影响.  相似文献   
997.
以125Ⅰ-LDL为配体对食管癌、胃癌及其相应的正常组织进行了LDL受体水平的测定,同时分析了各组织中蛋白质、DNA的含量,以探讨食管癌和胃癌发生与LDL代谢之间的关系。结果显示,癌组织和正常组织的LDL受体亲和性差异无显著性,但癌变组织的蛋白质、DNA和LDL受体水平均明显高于相应正常组织。癌细胞需要大量的胆固醇满足其有丝分裂,细胞通过受体升高机制使LDLR增多,以增加对LDL的摄取和利用。  相似文献   
998.
Our new finding of de novo synthesis and secretion of C3 by both murine peritoneal macrophages and polymorphonuclear leukocytes (PMN) was confirmed by the incorporation of [35S]methionine into C3 molecules and their complete inhibition by cycloheximide. The methods of secretion of C3 from these two types of cells were compared by examining the C3 contents in their culture supernatants. Completely different modes of secretion were observed, i.e. although macrophages synthesize and secrete C3 constitutively, PMN has a mechanism to store the already synthesized C3 in the cell and secrete it in response to stimuli. Protein kinase C (PKC) activators, e.g. 12-O-tetradecanoyl-phorbol 13-acetate, dioctanoyl glycerol, and mezerein, as well as calcium ionophore A23187 stimulate the secretion of C3 from PMN. These results suggest the involvement of PKC and the calmodulin pathway. A very sensitive method for measuring C3 activity was developed which enabled us to show for the first time that C3 secreted by PMN had opsonizing activity and that particles cultured with PMN were phagocytosed effectively.  相似文献   
999.
硝酸铋与丙磺舒合用对顺铂肾毒性的防护作用   总被引:1,自引:0,他引:1  
毒性剂量的顺铂(CP30μmol·kg-1ip)可引起血尿素氮(BUN)升高。硝酸铋(BN)5μmol·kg-1于CP前48和24hse,丙磺舒(Pro)700μmol·kg-1于CP前15,1h及CP后5hig,或BN与Pro二者半量合用,按上述给药,均能抑制CP引起的BUN升高,尤以BN+Pro组抑制作用显著。肾脏光镜和电镜标本显示,CP使肾小管受损严重;BN组,Pro组和BN+Pro组均使CP引起的肾小管受损减轻,尤以BN+Pro组减轻明显。BN2.5-20μmol·kg-1剂量依赖性地诱导小鼠肾脏金属硫蛋白合成。Pro可使CP后24b肾铂含量明显降低;Pro或Pro+BN使尿铂累积排出量增加,血浆铂浓度降低。提示PFO防护CP肾毒性与其减少肾铂分布,增加尿铂排出有关。  相似文献   
1000.
Clinical studies have demonstrated that measures of cell-mediated immune function are altered in bereaved persons and depressed patients. This review article focuses on our recent observations of changes in T cell subpopulations and natural killer cytotoxicity in women undergoing adverse life events including conjugal bereavement. A reduction in natural cytotoxicity has also been found in depressed patients. The mechanism by which psychologic states might influence immune function is discussed.  相似文献   
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