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291.
Neuroscience and Behavioral Physiology - Olfactory bulbectomy in rodents is widely used as a model of the symptoms of clinical depression and neurodegeneration, including cholinergic. Male C57BL/6...  相似文献   
292.
293.
Aim of the study was comparative assessment of hypotensive, antiischemic efficacy and effect on left ventricular (LV) diastolic function of calcium antagonists, angiotensin converting enzyme inhibitor and blockers of beta-adrenoreceptors. RESULTS: The data obtained evidence that at monotherapy most pronounced lowering of arterial pressure is observed during use of verapamil CR or amlodipine. Therapy with all studied drugs led to significant decrease of number of episodes of ST-segment depressions, their duration and amplitude during 24 hours. Greatest decrease of frequency of episodes of ST-segment depression was observed during therapy with heart rate reducing calcium antagonists. Disturbed LV diastolic function improved under action of calcium antagonists and beta-adrenoblockers did not change during therapy with angiotensin converting enzyme inhibitor. Diminishment of severity of disturbance of diastolic function under influence of pulse slowing calcium antagonists was associated in the first place with augmentation of LV filling in the first phase of diastole, but during therapy with amlodipine and beta-adrenoblockers - with decrease of contribution of systole of the left atrium. beta-adrenoblockers and diltiazem improved LV diastolic function in patients with episodes of painless myocardial ischemia. CONCLUSION: Comparative assessment of hypotensive action of preparations from three groups revealed that greatest lowering of arterial pressure occurred during monotherapy with verapamil SR and amlodipine. The stadied drugs differently affected damage of a target organ - the heart - in patients with AH.  相似文献   
294.

BACKGROUND AND PURPOSE

The P2X7 receptor is implicated in inflammation and pain and is therefore a potential target for therapeutic intervention. Here, the development of a native tissue radioligand binding, localization and ex vivo occupancy assay for centrally penetrant P2X7 receptor antagonists is described.

EXPERIMENTAL APPROACH

Autoradiography studies using the P2X7 antagonist radioligand [3H]-A-804598 were carried out in rat brain and spinal cord. Subsequent in vitro binding and ex vivo occupancy assays were performed using rat cortex homogenate.

KEY RESULTS

P2X7 expression was shown to be widespread throughout the rat brain, and in the grey matter of the spinal cord. In binding assays in rat cortex homogenate, ∼60% specific binding was achieved at equilibrium. In kinetic binding assays, kon and koff values of 0.0021·min−1·nM−1 and 0.0070·min−1 were determined, and the Kd derived from kinetic measurements was consistent with that derived from saturation analysis. Novel P2X7 antagonists inhibited the binding of [3H]-A-804598 to rat cortex P2X7 receptors with Ki values of <40 nM. In an ex vivo occupancy assay, a P2X7 antagonist dosed orally to rats caused a concentration-dependent inhibition of the specific binding of [3H]-A-804598 to rat cortex.

CONCLUSIONS AND IMPLICATIONS

The present study describes the development of an assay that allows localization of P2X7 receptors, the measurement of the binding affinity of P2X7 receptor antagonists in native tissue, and provides a means of determining central P2X7 receptor occupancy. These assays could form an important part of a P2X7 drug discovery programme.  相似文献   
295.
The paper describes a case of hereditary thesaurismosis - galactosemia in neonate infant with mutation of GALT-gene (Q188R/N) and vascular malformation of the internal organs.  相似文献   
296.
目的:观察骨髓间充质干细胞移植治疗急性心肌梗死对血管内皮功能的影响。方法:实验于2005-09/2006-06在唐山工人医院中心实验室完成。①选用清洁级健康近交系SD大鼠40只,随机数字表法分为假手术组、模型对照组、干细胞移植组、细胞培养基组,10只/组。另取1只大鼠用于骨髓间充质干细胞的提取。②大鼠处死后无菌条件下分离股骨和胫骨,剔除肌肉、骨膜,剪一侧骨端,用10mL无血清DMEM低糖培养基冲出骨髓细胞后,收集冲洗液制成单细胞悬液,过滤离心,弃上清液,密度梯度法分离培养骨髓间充质干细胞。待细胞80%贴满培养瓶底时,用乙二胺四乙酸和胰蛋白酶混合消化传代。将4,6-二脒-2-苯基吲哚以50mg/L浓度加入第3代细胞培养基中,制成细胞悬液备用。③术前各组大鼠均行气管插管,建立急性心肌梗死模型,以远端供血区心肌组织颜色苍白、心电图检测Ⅱ导联ST段持续抬高为模型建立成功的标志。假手术组仅开胸予以前降支穿线但不结扎。④造模成功后1~3h,干细胞移植组用微量注射器吸取4,6-二脒-2-苯基吲哚标记好的第3代骨髓间充质干细胞悬液50μL,直接注入梗死区边缘的心肌组织。细胞培养基组按干细胞移植组的方法于相同部位注射等量无血清DMEM低糖培养基(pH值6.9)。⑤造模后4周处死各组大鼠,切取心脏组织,于梗死边缘区心肌组织制作切片,荧光显微镜下观察4,6-二脒-2-苯基吲哚标记的供体细胞。留取2mL全血,离心后抽取血清500μL,酶联免疫吸附法测定血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量。结果:40只大鼠均进入结果分析。①体外培养骨髓间充质干细胞的性状观察:从正常大鼠骨髓中分离培养的原代骨髓间充质干细胞,24~48h贴壁生长,短棒状;7~10d达到80%~90%融合;传至第3代骨髓间充质干细胞分布均匀,呈纺锤形。②各组心脏标本4,6-二脒-2-苯基吲哚标记移植细胞的存活状况:干细胞移植组可见成团及散在的4,6-二脒-2-苯基吲哚标记的阳性细胞,其余3组心脏标本中均未见荧光细胞。③各组大鼠血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量检测:与假手术组比较,模型对照组、细胞培养基组、干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均明显升高(P<0.01或0.05);与模型对照组比较,干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均有所降低[(3.37±0.14),(2.10±0.15)μg/L;(2.64±0.13),(1.74±0.06)μg/L;P均<0.05]。结论:骨髓间充质干细胞移植到实验性大鼠心肌梗死模型后成功存活,能降低血清中增高的细胞间黏附分子1与血管内皮细胞黏附分子1含量,提示骨髓间充质干细胞移植可能通过降低黏附分子的表达来改善血管内皮功能。  相似文献   
297.
A distinctive feature of this review is a critical analysis of methods and results of measurements of the optical properties of tissues in a wide spectral range from deep UV to terahertz waves. Much attention is paid to measurements of the refractive index of biological tissues and liquids, the knowledge of which is necessary for the effective application of many methods of optical imaging and diagnostics. The optical parameters of healthy and pathological tissues are presented, and the reasons for their differences are discussed, which is important for the discrimination of pathologies and the demarcation of their boundaries. When considering the interaction of terahertz radiation with tissues, the concept of an effective medium is discussed, and relaxation models of the effective optical properties of tissues are presented. Attention is drawn to the manifestation of the scattering properties of tissues in the THz range and the problems of measuring the optical properties of tissues in this range are discussed. In conclusion, a method for the dynamic analysis of the optical properties of tissues under optical clearing using an application of immersion agents is presented. The main mechanisms and technologies of optical clearing, as well as examples of the successful application for differentiation of healthy and pathological tissues, are analyzed.  相似文献   
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