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91.
目的 研究血小板激活因子拮抗剂SRI63-441对大鼠缺血再灌注损伤心肌的保护作用。方法 将实验大鼠分成3组,对照组未行缺血及药物治疗,再灌注组及SRI63—441治疗组结扎大鼠左冠状动脉前降支(LAD)缺血30分钟后,行再灌注10小时,其中治疗组结扎前1分钟给予SRI63—441(1mg/kg),观察大鼠再灌注心律失常,再灌注区心肌组织中丙二醛浓度、超氧化物歧化酶活性的变化。结果 SRI63—441能明显降低再灌注时室性心律失常的严重程度,使缺血30分钟再灌注10小时大鼠的心肌梗塞面积从21.6±3.1%降至12.7±2.5%,心肌组织中脂质过氧化最终产物丙二醛(MDA)含量下降,超氧化物歧化酶(SOD)活性升高。结论SRI63—441用于大鼠心肌缺血再灌注可减少心肌损伤,提示PAF为心肌再灌注损伤的重要介质,而PAF拮抗剂有可能用于心肌缺血再灌注损伤的治疗。 相似文献
92.
目的:观察自体干细胞动员对骨创伤大鼠的免疫功能的保护作用,为战创伤后的免疫抑制及继发性感染、系统性炎症反应等治疗提供依据。方法:挤压折断法复制大鼠双后肢股骨骨折模型,于致伤后0、24、48h连续给模型动物肌肉注射GM—CSF20μg/kg,致伤后72h细胞增殖法检测T、B淋巴细胞活性,ELISA法检测血清IL-1、IL-2、IFN-7、TNF—α浓度,自动系列化分析法检测C3、CA、IgM、IgG浓度,称重法观察脾重与体重的比例变化。结果:股骨骨折模型大鼠致伤后72h,GM—CSF动员骨髓干细胞组大鼠的T、B淋巴细胞活性和血清IFN-γ、IL-2浓度高于对照组(P〈0.01),IL-1、TNF—α浓度低于对照组(P〈0.01),血清C3、CA、IgM、IgG浓度及脾/体重比值高于对照组(P〈0.01)。结论:GM—CSF动员自体干细胞动员对大鼠骨创伤诱导的免疫功能抑制具有保护作用。 相似文献
93.
Objective To investigate the value of statistical parametric mapping 5 (SPM5) and its parameter settings in analysis of PET imaging for epilepsy patients. Methods Seventeen epilepsy patients and seventeen controls were scanned with PET. The datns were analyzed using PET and SPM5 with qualitative and semiquantitative analysis, statistical analysis of the percentage (numbers of agent distribution decreasing in focus to brain) for different parameters combinations, which were value adjustment to contral-p and voxels-k. Results There was decreasing of agent distribution at temporal lobe in epilepsy patients detecting with PET; the T/NT of focus to cerebellum was 1.07±0.24, the T/NT of normal tissue in opposite side to cerebellum was 1.27±0.18, there was a significant difference (t=1.87, P<0.05). Dealing with SPM5, there was more significant decreasing of agent in regions 19, 21, 39 of temporal lobe, regions 7, 19, 31, 40, 47 of parietal lobe and occipital lobe in epilepsy patients. With different value of k, the percentage was (27±22)%, (29±24)%, (32±23)%, (35±27)%, (39±31)%respectively, there was not significant difference (F=0.59, P>0.05) ; for different value of p, the percentage was (42±30) %, (29±25) %, (26±21) % respectively, with a significant difference (F=3.60, P<0.05); there was linear regression in value adjustment to contral-p and the percentage(b=-18.24, t=2.57, P<0.05). Conclusions Semiquantitative analysis by SPM5, the setting of value adjustment to contral-p would affect the results, the smaller of value adjustment to contral-p, the better of the result. SPM5 would be more objective and accurate to locate the focuses. 相似文献
94.
Leo Sher Juan J Carballo Michael F Grunebaum Ainsley K Burke Gil Zalsman Yung-yu Huang J John Mann Maria A Oquendo 《Bipolar disorders》2006,8(5P2):543-550
Objectives: Bipolar disorder is a severe illness that is associated with suicidal behavior. A biological predictor of highly lethal suicide attempts in patients with bipolar disorder would be valuable. We hypothesized that cerebrospinal fluid (CSF) monoamine metabolite levels are related to lethality of suicide attempts in bipolar patients and examined the relation between CSF 5-hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) levels and maximum lethality of suicide attempts at baseline and during a 2-year follow up.
Methods: Twenty-seven bipolar depressed patients participated in the study. Demographic and clinical parameters were examined and recorded. Lumbar punctures were performed and CSF 5-HIAA, HVA, and MHPG were assayed by high-performance liquid chromatography with electrochemical detection. Following discharge, patients were evaluated after 3 months, 1 year, and 2 years. Each follow-up interview included an in-depth assessment of suicidal behavior during the intervening time period.
Results: Six subjects made suicide attempts during the 2-year follow-up. Bipolar patients who attempted suicide during the follow-up period had higher aggression and hostility scale scores compared to bipolar subjects who did not make a suicide attempt during the follow-up period. CSF 5-HIAA, HVA, and MHPG levels were negatively correlated with the maximum lethality of suicide attempts during the 2-year follow-up period.
Conclusions: Our finding is the first observation that CSF monoamine metabolite levels may be predictors of lethality of suicide attempts in patients with bipolar disorder. Further studies are necessary to answer the question whether CSF monoamine metabolite levels are clinically useful biochemical predictors of highly lethal suicide attempts or completed suicides. 相似文献
Methods: Twenty-seven bipolar depressed patients participated in the study. Demographic and clinical parameters were examined and recorded. Lumbar punctures were performed and CSF 5-HIAA, HVA, and MHPG were assayed by high-performance liquid chromatography with electrochemical detection. Following discharge, patients were evaluated after 3 months, 1 year, and 2 years. Each follow-up interview included an in-depth assessment of suicidal behavior during the intervening time period.
Results: Six subjects made suicide attempts during the 2-year follow-up. Bipolar patients who attempted suicide during the follow-up period had higher aggression and hostility scale scores compared to bipolar subjects who did not make a suicide attempt during the follow-up period. CSF 5-HIAA, HVA, and MHPG levels were negatively correlated with the maximum lethality of suicide attempts during the 2-year follow-up period.
Conclusions: Our finding is the first observation that CSF monoamine metabolite levels may be predictors of lethality of suicide attempts in patients with bipolar disorder. Further studies are necessary to answer the question whether CSF monoamine metabolite levels are clinically useful biochemical predictors of highly lethal suicide attempts or completed suicides. 相似文献
95.
The mutational specificity of the syn dihydrodiol epoxide of 5-methylchrysene in the supF gene of the pSP189 vector was examined. Transversion mutations at GC pairs predominated with G → T and G → C changes accounting for 42 and 21% of total base change mutations. The types of mutations found reflect the previously determined chemical preference of this reactive species for reaction with deoxyguanosine residues in DNA. 相似文献
96.
97.
采用薄层扫描法对复脉定冲剂中远志有效成分3,4,5-三甲氧基反式肉桂酸乙酯的含量进行测定。方法简单、快速,结果可靠,可作为该制剂的质控标准。 相似文献
98.
Herman M. van Praag 《European neuropsychopharmacology》1992,2(4):393-404
5-HT disturbances in depression (as exemplified by lowered CSF 5-HIAA) are not syndrome specific but related to components of the depressive syndrome, specifically to increased anxiety and aggression. These 5-HT disturbances are probably core pathogenetic processes not derivative features. I hypothesized that in this subtype of depression, i.e. in “5-HT related depression”, the key psychopathological disturbances are dysregulation of anxiety and aggression, while mood lowering is a “by-product”. Based on this hypothesis it was predicted that agents which ameliorate anxiety and/or aggression via harmonization of 5-HTergic transmission will, in addition, exert overall antidepressant effect in “5-HT related depression”. The study of the relative “weight” of the various psychopathological components of depression is a basic exercise in understanding the nature of that condition and could, as such, greatly facilitate the goal-directed search for new and innovative antidepressants. 相似文献
99.
合成了3-取代苯基-5-取代-1,2,4-(口恶)二唑类化合物50个,经感染棘球蚴的小鼠初筛,部分化合物对棘球蚴有不同程度的作用,化合物13、28和30对棘球蚴的囊重抑制率分别为70、75.6和71.6%,其中化合物13对棘球蚴的生发层有损害作用。 相似文献
100.
O. F. M. SELLEVOLD T. M. BERG K. A. REIN O. W. LEVANG O–J. IVERSEN K. BERGH 《Acta anaesthesiologica Scandinavica》1994,38(4):372-379
A prospective randomized study was performed to investigate the effect of surface coating with covalently endpoint–attached heparin (Carmeda Bio Active Surface) and reduced general heparinization on haematological indices and complement C5 activation. Care was taken to optimize the rheological design of the system using centrifugal pump and a closed system without venting or machine suction. Twenty patients scheduled for aortocoronary bypass grafting (EF > 0.5) participated in the study. Ten patients were randomized to be treated with heparin–coated equipment (CBAS) and reduced i.v. heparin (1.5 mg kg-1) while 10 patients treated with identical but noncoated equipment and full heparinization (3 mg–kg-1) served in a Control group. A vacuum suction was used to collect the blood from the operating field and it was autotransfused at weaning from extracorporeal circulation (ECC). Blood samples were obtained from the venous (precircuit) and arterial (postcircuit) side. We used a new and very specific method for detection of C5a based on monoclonal antibodies. The concentration of C5a was low in both groups during the operation but a significant increase was seen on days 1 and 2. In the Control group there was an increase from 10.2 ngml-1±1.2 to 27.5 ng ml-1 ± 4.8 on day 2 and in the CBAS group from 10.7 ng ml-1 ± 1.2 to 35.6 ng ml-1 ± 11.6 on day 2 (NS between groups). The granulocytes and total leukocyte count increased at the end of ECC and was maintained at the elevated level throughout the study period. The amount of free haemoglobin was high in the autotransfused blood in both groups. The present results confirm the feasibility of reducing general heparin when using heparin–coated systems but the study does not support the superiority of such coating with regard to biocompatibility in short procedures with a Theologically optimized circuit. The potential benefit from reduced heparin and protamine has not been fully evaluated. 相似文献