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101.
Michio Kimura Kayoko Kurosawa-Ohsawa Mikiko Takahashi Masayoshi Koyama Shigeaki Tanaka Tetsuro Matsuishi 《Thrombosis research》1992,67(6):687-696
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C. 相似文献
102.
大鼠肝小肠联合移植模型的建立 总被引:1,自引:0,他引:1
孙晓毅 《中华器官移植杂志》1997,18(4):194-195
本文报告一种封闭群大鼠进行的肝小肠联合移植模型。术中供体肝与小肠整块游离和灌注,分开切取。供肝原位、供肠异位移植于受体大鼠。主要血管用Kamada袖套法吻合,正式实验21次,3天以上存活率为43%。结果表明:减少手术时间和简化操作技术是提高成功率的关键因素和基本原则。 相似文献
103.
A. Saija P. Princi R. De Pasquale G. Costa G. B. De Sarro 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,88(1):151-157
Summary The genetically epileptic-prone rat (GEPR) is a valuable model for the study of gene-linked abnormalities involved in epilepsy. In comparison with normal Sprague-Dawley controls, we found, in GEPRs, a marked depression in local cerebral glucose utilization, widespread throughout the brain. This depression was accompanied by a significant increase of blood-brain barrier permeability and a reduction in regional blood volume. Finally GEPRs showed lower plasma levels of total triiodothyronine than normal controls. One can speculate that alterations in cerebral metabolism and microvascular regulation and thyroid hormone imbalance may be gene-linked factors involved in seizure susceptibility. 相似文献
104.
A. Reinert A. Kaske S. Mense 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(2):174-180
The density of substance P (SP)-, calcitonin gene-related peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-immunoreactive
(ir) nerve endings was quantitatively evaluated in intact and inflamed gastrocnemius-soleus muscle of the rat. In persistently
inflamed muscle (12 days after a single injection of Freund’s adjuvant into the muscle), the density of SP-ir fibres was significantly
increased. CGRP- and VIP-ir fibres displayed an insignificant increase in density. The density of fibres ir for nerve growth
factor (NGF) and for growth-associated protein 43 (GAP-43/B-50), a marker for axonal sprouting, regeneration and synaptic
reorganisation, increased significantly in persistently inflamed muscle. The data are consistent with the established contribution
of NGF on the expression of SP and GAP-43 in afferent neurones under the influence of a persistent inflammation.
Received: 8 September 1997 / Accepted: 12 February 1998 相似文献
105.
Summary The serratus anterior muscle in the rat is supplied by the serratus division of thoracodorsal vessels, in a pattern similar to man [2]. The serratus anterior muscles were transferred to the groin area as a free muscle flap in 17 rats and as a free muscle graft in 13 rats. In the free muscle flap group, the serratus anterior muscles of 8 of 10 rats survived; histological examination showed them to be viable and the vascular anastomoses were patent at the 30th day. In the free muscle graft group, all of the muscle grafts became necrotic. As a result, it is concluded that the microvascular transfer of serratus anterior muscles in rats is a useful small animal model for microsurgical laboratory training of clinical free flap transfers and also for performing pharmacological and biochemical studies in transplanted muscle. 相似文献
106.
Previously, we determined the pattern of stress-induced c-fos mRNA expression throughout the brain in order to gain further insight into the identification of the neural circuits mediating stress-induced regulation of the hypothalamic-pituitary-adrenal axis. In the present study, we determined if rapid effects of increased glucocorticoid levels after stress contribute to changes in c-fos mRNA expression. To this end, stress-induced c-fos expression was characterized in adrenalectomized (ADX) or adrenalectomized and corticosterone replaced (ADX/B) male rats. Animals were sacrificed 30 min post-onset of a 10 min swim stress, and in situ hybridization histochemistry was used to detect c-fos mRNA throughout the brain. The pattern of c-fos induction in the ADX and ADX/B animals was similar to that observed in the sham operated animals. Additionally, densitometric measurements were made to quantify the c-fos response in the paraventricular nucleus of the hypothalamus and the CA1/2 region of the hippocampus. We found that ADX did not alter the magnitude of the c-fos response to stress in these areas, but there was a slight dampening of the response in ADX/B animals. In sum, these results suggest that the pattern of c-fos expression observed 30 min post-stress is independent of stress-induced increases in circulating glucocorticoid concentrations. 相似文献
107.
The sequence of rat hypothalamic pro-thyrotropin releasing hormone, deduced by sequencing of cDNA, in addition to 5 TRH progenitor genitor sequences contains leader, trailer and 4 intervening sequences separated by paired basic amino acid sequences. We have developed radioimmunoassays to synthetic peptides corresponding to portions of these cryptic proTRH sequences and have used these assays to identify and partially characterize proTRH peptides, distinct from TRH, in extracts of rat brain. Two of these peptides correspond closely in size to one intervening sequence and the car☐y-terminal sequence of proTRH. Three other peptides correspond to the intact amino-terminal leader sequence and two peptides formed by a further cleavage of the leader sequence at an internal paired basic amino acid sequence. 相似文献
108.
目的 探讨中药骨康对卵巢切除大鼠骨质疏松症的治疗作用。方法 选择6m龄SD大鼠48只。随机分为假手术模型组(Sham)、手术模型组(OVX)、尼尔雌醇组(E2)、中药骨康组。切除大鼠卵巢3m后。大鼠骨质疏松症模型制备成功,分别给予尼尔雌醇、中药骨康灌胃治疗,并与Sham组和OVX组对照。治疗3m后,体内双荧光标记,取第2腰椎包埋切片。全自动图像分析及松质骨骨形态计量学软件处理。观察中药对骨形态计量学参数的影响。结果 卵巢切除后大鼠骨小梁面积百分数(%Tb.Ar)下降35.84%,骨小梁数量(Tb.N)下降16.60%,骨小梁宽度(Tb.Th)下降25.79%,表明绝经后骨质疏松症动物模型成立。骨康治疗3个月后,与OVX组相比,Oc.N/mm^2下降42.80%,有显著性差异(P〈0.01);%Tb.Ar、Tb.Th、Tb.N和MAR有上升趋势(P〉0.05);15.Sp,%L.Pm、BFR/BS、BFR/TV和Oc.N/mm,BFR/BV有下降趋势(P〉0.05)。结论 中药骨康具有降低骨转换以及促进骨形成和抑制骨吸收的双重作用,说明中药骨康对骨质疏松有明显的治疗作用。 相似文献
109.
压迫及非压迫因素在实验性神经根性疼痛中的作用 总被引:6,自引:0,他引:6
目的:探讨压迫及非压迫因素在实验性椎间盘源性神经根性疼痛中的作用。方法:取大鼠白体脊椎关节突修剪后放置在L5神经根下.造成对L5神经根的直接压迫(压迫组);取大鼠白体尾椎椎间盘组织无压迫下放置在L5神经根表面(非压迫组):同时设立对照组。术后不同时间点测定各组大鼠后足底机械刺激疼痛阈值的变化。结果:压迫组与非压迫组大鼠后足底均产生了一个长时程机械刺激疼痛阈值的降低;与压迫组相比.非压迫组大鼠术后1天就开始出现了疼痛阈值降低(P〈0.05),明显早于压迫组大鼠,并且疼痛阈值降低更加显著:而压迫组大鼠术后1周时才出现明显的疼痛阈值降低(P〈0.05)。对照组大鼠疼痛阈值没有发生明显的改变。结论:尽管压迫和非压迫因素都参与椎间盘源性神经根性疼痛的发生.但二者作用的时间不同+在椎间盘突出的早期阶段非压迫因素可能在疼痛中起着重要的作用:随后压迫因素可能逐渐成为致痛的主因。 相似文献
110.
The cytotoxic effects of propyl gallate (PG), its related gallates and gallic acid have been studied in freshly isolated
rat hepatocytes. Addition of PG (0.5–2.0 mM) to hepatocyte suspension elicited concentration-dependent cell death accompanied
by losses of intracellular ATP, adenine nucleotide pools, glutathione (GSH) and protein thiols. The rapid loss of intracellular
ATP preceded the onset of cell death caused by PG. In the comparative toxic effects of PG and related gallates at concentration
of 1 mM, octyl gallate (OG), dodecyl gallate (DG) and butyl gallate (BG) elicited an abrupt depletion of ATP, followed by
an acute cell death. These gallates were more toxic than PG; the toxic effects of PG were similar to those of methyl gallate
(MG) and ethyl gallate (EG). In mitochondria isolated from rat liver, PG caused a concentration-dependent increase in the
rate of state 4 oxygen consumption, indicating an uncoupling effect. The rate of state 3 oxygen consumption was inhibited
by OG and DG. According to the respiratory control index, the order of impairment potency to mitochondria was OG>BG, DG>PG>EG,
MG>gallic acid. These results indicate that PG and related gallates are toxic to hepatocytes and that the acute cytotoxicity
may be due to mitochondrial dysfunction.
Received: 16 May 1994 / Accepted: 15 August 1994 相似文献