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41.
EffectsofPhentolamineonHemorrheologyandHemodynamicsinDogswithAcuteLiverDamageDANZili(但自力);ZHANGWenying(张文英);LIShaobai(李绍白)(In... 相似文献
42.
作者选用SD大鼠进行腹腔内一次性注入百草枯25mg/kg后,在7个不同时间点观察其肺病理组织和超微结构改变。结果显示:百草枯可引起弥漫性毛细血管内皮细胞和肺泡1型上皮细胞为主的整层气一血屏障结构的损害,主要表现为肺泡水肿、出血、透明膜形成和(或)程度不等的肺泡炎,当损伤不能完全修复时则局部终结为纤维化。 相似文献
43.
以肝、脾组织中过氧化脂质(LPO)含量及谷胱甘肽过氧化物酶(GSHL-Px)活性为指标探讨硒的辐射防护效应。实验结果表明:BALB/C纯系雄性小鼠经3Gy ~(60)Co γ射线照射后3天,肝、脾组织LPO生成量比未照射者均显著增多,而GSH-Px活性却都显著降低;但于照射前连续7天每日经口灌胃亚硒酸钠溶液0.2ml(含硒12.5μg)的实验组动物,肝、脾组织LPO含量均明显少于照射对照组,而GSH-Px活性都显著高于照射对照组,结果提示,通过降低LPO含量和增加GSH-Px活性,硒对小鼠可能有辐射防护作用。 相似文献
44.
S Kimel L O Svaasand M Hammer-Wilson V Gottfried S Cheng E Svaasand M W Berns 《Lasers in surgery and medicine》1992,12(4):432-440
The chick chorioallantoic membrane (CAM) model was used to study vascular effects of photodynamic therapy (PDT) and hyperthermia (HPT) and the synergism of these modalities. The CAM is a convenient medium for monitoring the modifications of the vasculature. It is possible to view the CAM and to examine structural changes of individual blood vessels in real time. Moreover, the CAM is a closed system which lends itself to mathematical modeling of the temporal and spatial temperature profile and in which HPT can be performed quantitatively and to a selected depth, using different lasers. A porphyrin-type photosensitizer solution was applied to areas of the CAM, defined by teflon O-rings placed on the surface. Uptake dynamics of the sensitizer into the CAM was determined by analyzing its fluorescence in vivo. The CAM area was irradiated with a dual-wavelength laser system composed of a dye laser at 644 nm (to induce PDT) and a CO2 laser at 10.6 microns (to bring about HPT). Damage to the CAM vasculature, due to combined PDT+HPT, was compared to the outcome of the separate modalities, and a synergistic effect of about 40% was observed. 相似文献
45.
46.
Summary Right brain-damaged patients with left spatial neglect were examined on a tactile maze task. They started to explore the right side of the maze and their search times were longer on the left side. Their performance was the same whether blindfolded or not, which contrasts with the results of other studies and probably reflects differences in task demand. The present results do not support a previous observation that visual neglect can be compensated through the tactile modality. Our patients had markedly longer search times than normal controls in the right as well as the left hemifield, and search times in both hemifields were positively correlated. The outcome of the maze test in this context may therefore depend to a large extent on impaired topo graphical processing. 相似文献
47.
铅是一种对全身组织有广泛亲和力的毒物,作用的基点是体内一些生物大分子(蛋白质、脂类、核酸),进而使大分子受损,影响到细胞功能. 相似文献
48.
小鼠持续性脑缺血后NMDA受体亚单位表达的变化 总被引:7,自引:1,他引:6
目的:研究小鼠持续性脑缺血后不同脑区NMDA受体亚单位表达的变化及其与病理损伤之间的联系。方法:采用大脑中动脉阻断法制作小鼠持续性脑缺血模型,取缺血后不同时间的皮层、海马、皮层下脑组织,用免疫印迹技术测定NMDA受体亚单位ζ1和ε1及ε2蛋白的含量。同时作冰冻切片和苏木素伊红染色,计算相应脑区神经元密度。结果:NMDA受体ζ1和ε1及ε2亚单位表达的改变发生于缺血后5h内,皮层下3个亚单位表达均明显增加,海马则各亚单位表达变化不一。脑梗塞灶和相关脑区神经元密度显著减小均出现于缺血后5h,相关脑区神经元死亡严重程度依次为皮层下组织和海马CA1区及大脑颞叶皮层Ⅲ-Ⅳ层。结论:小鼠持续性脑缺血,缺血侧脑组织NMDA受体亚单位ζ1和ε1及ε2表达的变化发生在明显的病理损害之前,表达变化程度因脑区不同,与相关脑区神经元损害的程度相应。 相似文献
49.
Summary The devastating neuropathological changes wrought by the intrathecal administration of vincristine are reported, with a detailed account of the widespread lesions in the brain and spinal cord, found in post-mortem light- and electron-microscope studies. 相似文献
50.
Summary
The compartment syndrome (cs) is characterized by an increased tissue pressure in a limited space. Pathophysiologically, it
is a multifactorial disease that is potentially induced by an initial trauma and develops according to the existence of cofactors.
Cofactors are, for instance, the circulation of the patient and the initial treatment of the impending cs. In particular,
the microcirculation is altered with endothelial destruction, development of a capillary leak, protein loss from intravasal
space and the development of an interstitial and intracellular third space. An impaired drainage of the lymphatic and venous
system causes a venous infarction. An arterial infarction results if the tissue pressure exceeds the arteriolar pressure.
An accompanying ischemia reperfusion mechanism increases the trauma load. In disadvantageous cases, the patients are in danger
of developing a multi-organ deficiency syndrome (MODS) by an uncontrolled inflammatory reaction, by intravasal volume loss
and by a myonephropathic systemic reaction. Clinically, the patients suffer a disproportionate amount of pain, followed by
neurological signs. Especially in noncompliant patients, tissue pressure measurement is useful. Resuscitation of the circulation
as well as splitting of casts is important. In case of a manifest cs, dermatofasciotomy has to be performed as an emergency
operation. Even if cs is diagnosed early and fasciotomy is carried out early, the development of sequellae cannot be avoided
in every single case.
相似文献