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101.
102.
目的为研究超急性排斥反应及对策,建立异种胰腺移植模型。方法以豚鼠和大鼠为供受者,用袖套法吻合静脉建立异种全胰十二指肠移植模型。结果共行 42次手术,成功 38例,均有内分泌功能,移植有效率为 100%。结论本模型具有操作简单,冷缺血及腹主动脉阻断时间短,不易形成血栓及吻合口漏等优点,为一较实用的研究异种胰腺移植模型。 相似文献
103.
蛔虫变应原致过敏性鼻炎豚鼠模型建立 总被引:2,自引:0,他引:2
为了建立蛔虫变应原致过敏性鼻炎的实验动物模型,将健康豚鼠30只,随机分为致敏组(n=20)和对照组(n=10)。致敏组经腹腔、四肢皮下注射蛔虫变应原免疫4周后,鼻腔雾化吸入蛔虫变应原;对照组以生理盐水代替变应原。结果致敏组18只出现鼻痒、喷嚏、流清涕等过敏性鼻炎的临床症状(评分〉5分),鼻腔分泌物涂片见大量嗜酸性粒细胞,以及鼻粘膜水肿、粘膜嗜酸性粒细胞和肥大细胞浸润等组织学变化,而对照组无上述变化 相似文献
104.
猪肝样品中铝含量的测定 总被引:2,自引:0,他引:2
任大林 《天津医科大学学报》2000,6(1):24-25
目的介绍用石墨炉原子吸收分光光度法测定猪肝中铝含量的方法.方法样品在聚四氟消解器中消解.采用标准加入法在石墨炉原子吸收光度计上测定铝的含量.结果分析了8份猪肝样品,平均铝含量(4.10±0.17)μg/g,变异系数为4.3%.铝测定的回收率为96.3%±3.28%.用人发标样测定了方法的准确度为(13.1±1.8)μg/g,标准为(13.3±2.3)μg/g.结论这是一种准确、精密、可靠的分析方法.本方法也适用于其他生物组织样品中铝含量的测定. 相似文献
105.
环孢菌素A外用实验研究 总被引:1,自引:0,他引:1
目的 从定性、定时二方面探讨环孢菌素A透皮能力。方法 通过对豚鼠的活体、体外透皮实验及抑制实验测定CYA透皮能力。结果 (1)环孢菌素A在活体透皮实验中,在促渗剂相同的条件下,随CYA浓度增加透皮量增加。(2)环孢菌素A在活体秀皮实验中,在相同的CYA浓度条件下加入促渗剂氮酮透皮量多于加入丙二醇透皮量。(3)环孢菌素A在离体透皮实验中,在促渗剂相同的条件下随CYA浓度增加透过量增加。(4)环孢菌素 相似文献
106.
STR-PCR方法检测贵州小型香猪遗传变异性的研究 总被引:5,自引:0,他引:5
目的 准确分析贵州小型香猪种群遗传变异及近交程度。方法 采用10对短串联重复序列(STR)引物,对贵州小型香猪个体进行PCR检测。结果 在检测到的88个有效等位基因型中,纯合基因型50个,占55.7%。个体平均杂合率为0.4081,位点平均杂合率为0.5562。结论 贵州小型香猪具有一定遗传稳定性,符合封闭群动物遗传学特征。 相似文献
107.
豚鼠至大鼠异种小肠移植超急性排斥的初步观察 总被引:1,自引:0,他引:1
目的 建立袖套法豚鼠至大鼠异种小肠移植模型,初步观察异种小肠移植超急性排斥反应的过程。方法 行异种异位全小肠移植,移植小肠脾性系膜上动脉(腹主动脉)与受体肾以下腹主动脉作端侧吻合,切除受体左肾,移植小肠肠系膜上静脉(门静脉)与受体左肾静脉行袖套吻合;在手术显策镜下观察超急性排斥的大体变化。结果 共实施异种小肠移植40例,成功34例,供受体手术时间平均150min,血管吻合成功率达90%。再灌流后1 相似文献
108.
Elliot Peter J. Bartus Raymond T. Mackic Jasmina B. Zlokovic Berislav V. 《Pharmaceutical research》1997,14(1):80-85
Purpose. The ability of intravenous (i.v.) infusions of the bradykinin agonist, RMP-7, to permeabilize the blood-ocular barriers (BOB) to the antiviral agent ganciclovir was investigated in guinea-pigs.
Methods. Different i.v. dosing regimens included pre-treatment with RMP-7 (0.2 g/kg/min for 5 min) followed by either [3H]-ganciclovir (1 Ci/0.2 ml/min) alone, and/or co-infusion with RMP-7 and [3H]-ganciclovir. At specific times the animals were sacrificed, their eyes removed, and the retina and lens epithelium dissected and analyzed for the amount of radioactivity.
Results. Using the ratio of tissue vs. integrated plasma radioactivity concentration, a two-fold increase in ganciclovir steady-state levels were observed in the retina as well as lens epithelium following RMP-7 pretreatment. Peak uptake effects were achieved with a 4.5 min ganciclovir infusion. Neither longer infusions of ganciclovir alone, nor co-infusions of RMP-7 and ganciclovir further enhanced the uptake effects. Kinetic analysis indicated that RMP-7 increased the rate of ganciclovir entry (K
IN) in studied ocular tissues, while the efflux of drug (K
OUT) was not affected by this treatment. Finally, ganciclovir retina:plasma ratios elevated by RMP-7 pre-treatment, remained higher than control ratios within 60 min following cessation of 4.5 min ganciclovir infusion.
Conclusions. These data offer further evidence that BOB and in particular the blood-retinal barrier can be permeabilized via bradykinin receptor stimulation. As the i.v. infusions of RMP-7 enhanced the retinal uptake of ganciclovir, it is suggested that a combination of RMP-7 and ganciclovir may provide a novel approach for treating cytomegalo-virus retinis. 相似文献
109.
Exogenous insulin-like growth factor II enhances post-infarction regional myocardial function in swine 总被引:1,自引:0,他引:1
BATTLER A.; HASDAI D.; GOLDBERG I.; OHAD D.; DI SEGNI E.; BOR A.; VARDA-BLOOM N.; VERED Z.; KORNOWSKI R.; LAKE M.; NASS D.; SAVION N. 《European heart journal》1995,16(12):1851-1859
OBJECTIVES: Insulin-like growth factor II (IGF-II) promotes cardiac myocytegrowth and contractility in vitro. This study was designed toinvestigate the effect of exogenous IGF-II on regional myocardialfun ction at the area of infarct in the pig. METHODS: Myocardial infarction was induced in 12 female anoesthetizedpigs by affigel blue beads, embolizing microvessels of the leftanterior descending coronary artery distribution. In the experimentalgroup (n=6), IGF-II (0.12 µg. kg1 in two animalsand 0.6 µg. kg1 in four) was incorporated intothe beads and delivered by them to the infarct area. Myocardialfunction was followed echocardiographically, and the excisedheart was analysed immunohistochemically and histopathologically. RESULTS: Myocardial function in injured zones, inversely related to anechocardiographic segmental wall motion score (mean ±SEM), was similar between the two groups at baseline, but at4 weeks post-infarction was significantly (P=0.008) reducedin the control group (0.58± 0.38 vs 3.42 ± 0.84),in contrast to nearly baseline values in the experimental group(0.58 ± 0.33 vs 1.17 ± 0.42, P=0.41). Cardiacperformance in injured segments was sign better after myocardialinjury in the experimental group (P=0.04). Tissue samples fromboth groups (4 weeks post-infarction), stained with haematoxylinand eosin demonstrated pen-infarct myocyte hypertrophy, correspondingto regions selectively stained by an antibody for CD56, whichhighlights growing cardiac myocytes. By image analysis semi-quantification,staining for CD56 was significantly (P=0.04) higher in the peri-infarctregion of the experimental group, as compared with controls(106.5 ± 2.8 vs 92 ± 4.4 gray level units). Microvesselsstained for von-Willebrand factor were similar in nwnber inboth groups (P=0.8), as were mesenchymal cells stained for vimentin(P=0.7). CONCLUSIONS: Exogenous IGF-II, delivered to the infarct area amelioratesregional cardiac function in the pig, perhaps by inducing peri-infarctmyocyte growth. 相似文献
110.
Stefania Meini Paolo Santicioli Carlo Alberto Maggi 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(1):79-86
The guinea-pig ureter was placed in a three-compartment organ bath to enable the application of electrical stimuli or drugs to its renal end (R site), the middle region (M-site) or the bladder end (B-site) while recording mechanical activity at the R- and B-sites. All experiments were performed in ureters pre-exposed to capsaicin (10 M for 15 min) to prevent the release of sensory neuropeptides from afferent nerves. Electrical field stimulation (EFS, 5–25 ms pulse width, 20 V) produced a phasic contraction at the site of stimulation (direct response to EFS) which propagated to the other end of the ureter. Section of the ureter at the M-site abolished the propagated response to EFS; after section, EFS applied at the M-site induced a phasic contraction at both the R-and B-sites. Likewise, the application of KCl at the M-site produced phasic contractions at both the R- and B-sites. Tetrodotoxin (1 M), nifedipine (1 M) or Bay K 8644 (1 M) applied at the M-site had no influence on the direct or propagated responses to EFS; nifedipine (10 M) applied at the M-site abolished the propagated responses without affecting the direct responses to EFS. Bay K 8644 (1 M) applied at the R-site produced a marked enhancement of the direct response (EFS applied at R-site) while having no effect on the amplitude of the propagated response to EFS. Nifedipine (1 M), applied at the R-site, produced a graded, time-dependent, inhibition of the direct response (EFS applied at R-site) and eventually suppressed it; the propagated response was unaffected until suppression of the direct response, when an allor-none blockade of the propagated response was observed. When applied at the B-site (EFS at Rsite), 1 M nifedipine produced a graded, time-dependent, inhibition of the propagated response and eventually suppressed it, without affecting the direct response to EFS. For further pharmacological analysis of drug action on the propagated activity, EFS was applied at the R-site and drugs were applied at the M-site. Human CGRP (CGRP, 0.1 M) or cromakalim (1-3 M) were applied in superfusion at the M-site in the absence or presence of glibenclamide (1 M). Neither drug affected the direct response to EFS; both CGRP and cromakalim produced a reversible suppression of the propagated response. Glibenclamide suppressed the inhibitory activity of 1 M cromakalim and partly antagonized the effect of CGRP; the blockade by glibenclamide was partly overcome by 3 M cromakalim. The present findings are consistent with the idea that propagation of excitation occurs because of the spread of electrical activity between smooth muscle cells of the ureter and that conduction of impulses is independent of local changes in contractility. The present results also demonstrate that CGRP induced a conduction block along the ureter and that this effect involves activation of glibenclamide-sensitive K channels. Therefore, a local release of CGRP in response to pathophysiological stimuli is, in principle, capable of suppressing ureteral peristalsis and antiperistalsis. 相似文献