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991.
肝钳与肝门阻断的肝损害及其防治的实验研究 总被引:2,自引:0,他引:2
本实验观察不同阻断时刻肝钳与肝门阻断的肝损害以及预防性应用抗氧化剂的缓解作用。结果表明:(1)SGPT、TB在肝钳组的变化比肝门阻断组表现得更为一过性。而肝门阻断给药组的改变要比非给药组的轻微且恢复得快。(2)肝门阻断时,MDA含量显著升高,机体的T-AOC和SOD下降。而给药组可明显减轻上述改变。(3)随着肝门阻断时间的延长,肝组织损害也相应加重,抗氧化剂的给予缓解了肝缺血和再灌注造成的组织损害。肝钳组由于健肝血供未受干扰,因此,不同阻断时刻肝组织学形态与对照组相似无甚改变。结论:(1)肝钳较肝门阻断的肝损害轻,且实用安全。(2)肝门阻断预防性使用抗氧化剂,可明显减轻肝缺血再灌注损害。(3)肝门阻断时经门静脉较外周静脉输注抗氧化剂,其保护作用更直接、明显 相似文献
992.
酞丁安对映体合成及其抗单纯疱疹病毒活性评价 总被引:1,自引:0,他引:1
酞丁安(3-酞酰亚胺-2-氧-正丁醛双缩氨硫脲,TDA)是药物研究所创制的抗病毒新药。为了研究其对映异构体(R),(S)-TDA对病毒活性及毒性是否有差异,并与消旋酞丁安(RS)-TDA的抗病毒活性及毒性进行比较,本文分别用已知构型的(R)-与(S)-丙氨酸为原料,通过缩合等6步反应,得到光学活性的(R)-,(S)-TDA,并与外消旋酞丁安比较其抗病毒活性及毒性。三者的抗单纯疱疹病毒活性与对细胞的毒性差别不大,说明消旋酞丁安临床使用是安全有效的。 相似文献
993.
中西医结合治疗胫腓骨开放性骨折82例 总被引:1,自引:0,他引:1
对82例胫腓骨开放性骨折,采用中西医结合治疗收到良好效果,治疗中主张在彻底清创的基础上使开放性骨折变为闭合性骨折,外固定时要求患者呈坐位,让伤肢自然下垂悬空,利用肢体的垂直重力作用使骨折正确复位,再根据具体情况进行有效的外固定。少用内固定,在用药方面,根据骨折治疗的不同时期采用中西药结合的辨证论治,同时强调早期进行功能锻炼。 相似文献
994.
Select types of supporting cell in the inner ear express aquaporin-4 water channel protein 总被引:14,自引:0,他引:14
Yutaka Takumi Erlend Arnulf Nagelhus Jo Eidet Atsushi Matsubara Shin-ichi Usami Hideichi Shinkawa Søren Nielsen Ole Petter Ottersen 《The European journal of neuroscience》1998,10(12):3584-3595
Aquaporins (AQPs) confer a high water permeability on cell membranes and play important parts in secretory and absorptive epithelia in kidney and other organs. Here we investigate whether AQPs are expressed in the sensory epithelia of the inner ear, where a precise volume regulation is crucial. By use of specific antibodies it was found that the inner ear contains AQP1 and 4 while being devoid of detectable levels of AQP2, 3 or 5. Immunofluorescence and postembedding immunogold labelling revealed a strictly non-epithelial distribution of AQP1, confirming previous data. In contrast, AQP4 protein and mRNA (visualized by in situ hybridization) were concentrated in select types of supporting cell, including Hensen's cells and inner sulcus cells. Immunogold particles signalling AQP4 were confined to the basolateral plasma membrane of Hensen's cells and to the basal plasma membrane of Claudius cells and inner sulcus cells. AQP4 was also found in supporting cells of the vestibular end organs, but was absent from transitional epithelial cells and dark cells. Strong labelling for AQP4 and AQP4-mRNA was associated with the central part of the cochlear and vestibular nerves. Hair cells were consistently unlabelled. Our findings indicate that AQP4 may facilitate osmotically driven water fluxes in the sensory epithelia of the inner ear and thus contribute to the volume and ion homeostasis at these sites. 相似文献
995.
The Effects of Serum from Patients with Acute Liver Failure on the Growth and Metabolism of Hep G2 Cells 总被引:6,自引:0,他引:6
In many bioartificial liver systems currently being designed and evaluated for use in fulminant hepatic failure, direct contact is required between the patient's blood and the liver cells in the device. The efficacy of such devices will be influenced by the interaction of fulminant hepatic failure (FHF) patient serum with the cells. We have found that FHF serum inhibits the growth rate and the synthesis of DNA, RNA, and protein; disturbs glutathione homeostasis; and induces morphological changes in cultured human Hep G2 cells. These interactions should influence the design of bioartificial liver devices based on proliferating cell lines and indicate the requirement to pretreat FHF patient plasma to reduce the toxin load. 相似文献
996.
王昭礼 《中国骨与关节损伤杂志》1993,(3)
本文介绍作者自行设制的多枚螺栓内固定治疗不同类型的新鲜股骨颈骨折76例。经3~12年随访,功能恢复优良率为88.2%,骨不愈合率为6.5%,股骨头缺血坏死率为10.6%。螺栓内固定具有稳定可靠的加压作用,使两骨折端紧密对合、互相嵌插,促进骨折愈合。 相似文献
997.
Effects of hepatoportal osmo-receptive (or sodium-receptive) afferents on neurons within the dorsal motor nucleus of the vagus (DMV) were investigated electrophysiologically in urethane-chloralose anesthetized rats. Responses of 56 spontaneously active neurons to antidromic stimulation of the ventral trunk of the subdiaphragmatic vagus were recorded in the left DMV. Among them, 35 neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve (inhibitory neurons), except two neurons that were slightly excited. Effects of portal infusion of 3.6% NaCl were examined on 26 inhibitory neurons. Sixteen neurons increased their discharge rates and one neuron decreased its discharge rate in response to portal infusion of hypertonic saline. Thirty-five DMV neurons responded to electrical stimulation of the dorsal trunk of the subdiaphragmatic vagus were inhibited by electrical stimulation of the hepatic branch of the vagus. Four neurons were excited by this stimulation. Relatively smaller number of neurons (5 out of 22 inhibitory neurons) increased their discharge rates in response to portal infusion of hypertonic saline. In conclusion, the response of DMV neuron observed in this experiment was characterized by increasing the frequency of spike discharges in response to portal infusion of hypertonic saline. However, these neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve. These results suggest that the hepatoportal osmoreceptive afferents may be conveyed to the DMV via inhibitory synapses. 相似文献
998.
Further study on the vascular basis for the reimplantation of the hand amputated through the palm 总被引:1,自引:0,他引:1
Summary Based on the anatomic data obtained from earlier studies on the vascular anatomy of the hand, the vascular architecture in the palm of the hand was studied on 60 sides of unembalmed adult upper extremities. Each palm was divided into 64 squares by 8 sagittal and 8 transverse sections. The vascular architecture in these squares and the arterial relations between them were observed and measured by angiography, operative microscopic dissection and computerised three-dimensional reconstruction. According to the pattern of the blood-vessels, the amputated palms can be classified into 4 types. The anatomic basis for the vascular anastomosis in each type is defined. There are three key-areas for the blood-supply of the palm and their significance is discussed. Apart from the 4 types of transversely amputated palms, the repair programe of the blood-vessles in 4 types of common obliquely amputated palms are also discussed.
Etude complémentaire de l'anatomie vasculaire de la main pour la réimplantation des amputations transpalmaires
Résumé Sur la base de données anatomiques obtenues lors de précédents travaux sur l'anatomie vasculaire de la main, l'architecture vasculaire palmaire a été étudiée sur 60 extrémités supérieures de cadavres d'adultes, non embaumés. Chaque paume a été divisée en 64 carrés par 8 sections sagittales et 8 sections transversales. L'architecture vasculaire à l'intérieur des carrés et les relations artérielles entre eux ont été étudiées et mesurées par angiographie, dissection au microscope opérateur et reconstruction computérisée en 3D. Les paumes amputées ont été regroupées en 4 types d'après la distribution des vaisseaux sanguins. Les données anatomiques concernant les anastomoses vasculaires sont précisées. Il existe trois zones clés pour l'irrigation de la paume. Leur importance quant à l'irrigation de la main est exposée. Outre la division des paumes amputées transversalement en 4 types, le programme de réparation de vaisseaux dans les 4 types d'amputations obliques communes de la paume et aussi discuté.相似文献
999.
新建废物处理和处置设施的选址是一项综合性很强的工作,涉及自然环境,社会政治和经济、安全和技术等诸多方面,选址的主要目标通过一系列的选址技术的步骤来具体体现。 相似文献
1000.
Human lymphocytes (HL) as well as lymphocytes (RL), hepatocytes (RH), and gastric mucosa cells (GM) of Sprague-Dawley rats were treated in vitro for 1 h with methylmercury chloride (MMC, 0.5–4 μg/ml) and dimethylmercury (DMM, 5–40 μg/ml). The cytotoxicity of the two organic mercury compounds was assessed by dye exclusion, and the extent of induced DNA fragmentation was measured with a single-cell microgel electrophoresis assay. Both MMC and DMM induced DNA damage and cytotoxicity in a dose-related manner in HL, RL, and GM. MMC was more effective in causing a significant increase in median DNA migration than DMM at doses yielding approximately the same degree of cytotoxicity. In rat hepatocytes the MMC-induced DNA damage was, however, lower than in the other cells. An analysis of repair kinetics following exposure to 2 μg/ml MMC was carried out in human lymphocytes obtained from an adult male donor. The bulk of DNA repair occurred 90 min after in vitro exposure, and it was about complete by 120 min following cessation of exposure. Finally, in order to have a basis for extrapolating to the human situation, in vivo studies were performed with Sprague-Dawley rats, also assessing the DNA damage and cytotoxicity in the lymphocytes and gastric mucosa cells. These in vivo results after oral exposure may be directly compared to the in vitro data obtained in the same cells. © 1993 Wiley-Liss, Inc. 相似文献