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31.
The gastrointestinal distribution of glycinin in pigs at different growth stages was investigated in this study. Fifteen healthy General No. 1 barrows weaned on the 28th day were randomly assigned to three groups with five replicates: five weanling, five growing and five finishing. All pigs received diets with non-soya bean ingredients in non-experimental periods, while the pigs received diets containing 4% purified glycinin in experimental periods. Binding of anti-glycinin antibody was detected using a labelled streptavidin–peroxidase complex method to determine the gastrointestinal distribution of glycinin. The results indicated that there was a significant difference on the gastrointestinal mucosal distribution of glycinin between pigs of different ages. Glycinin in growers was higher than piglets and lower than finishers (P<0.001). The highest content of glycinin was in the distal jejunum and ileum for piglets, and in distal jejunum for growers and finishers (P<0.05).  相似文献   
32.
目的观察经球囊导管阻断肝动脉高热灌注生理盐水行肝段热凝固CT表现。方法实验猪6头,选用球囊导管阻断肝段动脉血流进行热灌注,导管流出温度设置50~60℃之间。热灌注结束后即刻、14天,行肝动脉DSA检查和肝脏螺旋CT扫描,14天将实验猪全部处死,取出肝脏进行病理检查。结果热灌注后14天,6头实验猪均存活。DSA检查见靶段动脉闭塞,肝组织热灌注区显示充盈缺损。肝脏热灌注区CT影像学表现:热灌注结束后即刻,热灌注区显示大片状低密度改变,无明显强化,边缘显示模糊;热灌注后14天,CT平扫示肝脏热灌注区呈典型楔形低密度改变;CT增强示热灌注区显示"三环征",由内向外分为低密度无增强区、边缘强化带和移行区透明带。病理上取得6个热凝固灶,CT上低密度无增强区、边缘强化带和移行区透明带分别代表病理的凝固性坏死区、炎性充血带和纤维化带。结论增强CT能准确反映经动脉导管肝段介入性热毁损的病理改变,DSA价值有限。  相似文献   
33.
【摘要】目的:建立注射用糜蛋白酶中组胺类物质检查方法。 方法:采用组胺检查法对注射用糜蛋白酶中组胺类物质进行限度检查方法学研究,并与现行猫法进行比较研究。结果:加标回收率86%~117%;豚鼠法方法特异性(真阴性率)100%,灵敏度(真阳性率)70%,猫法方法特异性100%,灵敏度70%;四个实验室室内重复性分别为82%、75%、83%、81%;实验室间重复性为92.9%~96.4%.结论:该方法准确与猫法相当、重复性好,可作为降压物质检查法的替代方法。  相似文献   
34.
The genus Ebolavirus comprises several virus species with zoonotic potential and varying pathogenicity for humans. Ebolaviruses are considered to circulate in wildlife with occasional spillover events into the human population which then often leads to severe disease outbreaks. Several studies indicate a significant role of bats as reservoir hosts in the ebolavirus ecology. However, pigs from the Philippines have been found to be naturally infected with Reston virus (RESTV), an ebolavirus that is thought to only cause asymptomatic infections in humans. The recent report of ebolavirus‐specific antibodies in pigs from Sierra Leone further supports natural infection of pigs with ebolaviruses. However, susceptibility of pigs to highly pathogenic Ebola virus (EBOV) was only shown under experimental settings and evidence for natural infection of pigs with EBOV is currently lacking. Between October and December 2017, we collected 308 serum samples from pigs in Guinea, West Africa, and tested for the presence of ebolavirus‐specific antibodies with different serological assays. Besides reactivity to EBOV nucleoproteins in ELISA and Western blot for 19 (6.2%) and 13 (4.2%) samples, respectively, four sera recognized Sudan virus (SUDV) NP in Western blot. Furthermore, four samples specifically detected EBOV or SUDV glycoprotein (GP) in an indirect immunofluorescence assay under native conditions. Virus neutralization assay based on EBOV (Mayinga isolate) revealed five weakly neutralizing sera. The finding of (cross‐) reactive and weakly neutralizing antibodies suggests the exposure of pigs from Guinea to ebolaviruses or ebola‐like viruses with their pathogenicity as well as their zoonotic potential remaining unknown. Future studies should investigate whether pigs can act as an amplifying host for ebolaviruses and whether there is a risk for spillover events.  相似文献   
35.
Taking blood samples is a common method in biomedical and biological research using guinea pigs. However, most blood sampling techniques are complicated and highly invasive and may therefore not be appropriate for certain research topics concerning stress and reproduction. Thus, a non-invasive method to measure steroid hormones is critically needed. The aim of this study was the biological validation of corresponding enzyme immunoassays for the measurement of fecal cortisol, progesterone, estrogen, and testosterone metabolites in guinea pigs. We examined the effect of subcutaneous injections of ACTH or saline on fecal cortisol metabolites to investigate the suitability of fecal samples to monitor adrenocortical activity. Furthermore, we investigated whether fecal sex steroid metabolites accurately reflected endocrine changes observed in plasma samples during female estrous cycles and male puberty, respectively. In addition, we compared fecal testosterone metabolites of intact males, castrated males, and females to investigate the reliability of fecal samples in discriminating gonadal status of males. Concentrations of fecal cortisol metabolites were significantly increased following ACTH challenge, indicating that adrenocortical activity can be monitored via fecal samples. Secondly, in females, plasma and fecal gonadal steroids were significantly correlated in most subjects. The assay for testosterone metabolites, on the other hand, could not clearly discriminate between test groups. From these findings we conclude that fecal samples can be used for the non-invasive assessment of adrenocortical and female reproductive status in guinea pigs. Testosterone metabolism seems to be more complex and further investigations are needed to establish a more suitable assay.  相似文献   
36.
Pigs single inoculated with Ascaris suum eggs expel the majority of larvae between days 14 and 21 post inoculation (p.i.), but the role of the immune system in expulsion is unclear. To investigate the dynamics of immune responses before, during and after the expulsion of A. suum larvae, pigs inoculated with 10 000 A. suum eggs were sequentially necropsied. Ascaris suum gradually moved distally from days 10-14 p.i. and only a few larvae were left by day 21 p.i. Pronounced increases in mucosal A. suum-specific IgA antibody secreting cells (ASCs) were already found by day 10 p.i. especially in the proximal jejunum, while only small increases in parasite-specific IgM ASCs were observed by day 21 p.i. in both proximal and distal jejunum. No mucosal IgG ASC responses could be detected. Increases in systemic A. suum-specific IgG1, IgM and to a lesser extent IgA antibodies were observed, while IgG2 remained almost unchanged. The levels of eosinophils and mast cells in the small intestinal mucosa did not change throughout infection. The results demonstrate that both systemic and mucosal A. suum-specific effector mechanisms are strongly stimulated in A. suum single infections and indicate that mucosal IgA may be an important mediator in the expulsion of A. suum.  相似文献   
37.
38.
目的:探讨川芎嗪( ligustrazine,LIG)对离体豚鼠气道平滑肌( airway smooth muscle,ASM)的效应及机制。方法取正常豚鼠支气管,制作成气管螺旋条,随机分成LIG组、LIG+普萘洛尔组、LIG+阿托品组、LIG+硝苯地平组、LIG+格列苯脲组、对照组。分别观察ASM在静息张力下以及组胺所致的高张力下,各组不同LIG浓度对ASM的效应并比较各组间ASM舒张率。结果(1) LIG对离体豚鼠ASM静息张力以及组胺所致的高张力均具有舒张作用。(2)离体豚鼠ASM在静息张力下,与LIG组比较,LIG+普萘洛尔组在LIG浓度10-7~10-6.5 mol/L时,舒张作用明显受到拮抗( P <0.05)。 LIG +阿托品组、LIG+格列苯脲组在LIG浓度10-7.5~10-3 mol/L时,舒张作用没有明显差别(P>0.05)。 LIG+硝苯地平组在LIG浓度10-6~10-4 mol/L时,舒张作用明显加强( P<0.05)。(3)离体豚鼠ASM在组胺所致的高张力下,与LIG组比较,LIG+普萘洛尔组在LIG浓度10-6.5~10-5 mol/L时,舒张作用明显受到拮抗( P<0.05);LIG+阿托品组、LIG+格列苯脲组在LIG浓度10-8~10-3 mol/L时,舒张作用没有明显差别( P>0.05);LIG+硝苯地平组在LIG浓度10-6.5~10-5 mol/L时,舒张作用明显加强(P<0.05)。结论 LIG可对离体豚鼠ASM静息张力以及组胺所致的高张力产生明显的舒张作用,其效应的产生可能与竞争性激动β2受体以及抑制Ca2+内流有关,这为临床应用川芎嗪治疗支气管哮喘提供了理论依据。  相似文献   
39.
目的 探讨内皮素拮抗剂对紫外线诱导豚鼠色素沉着的治疗作用.方法 用中波紫外线(UVB)照射豚鼠皮肤制作色素沉着模型.模型制作成功后,模型动物分为空白对照组(生理氯化钠溶液)、内皮素拮抗剂组及熊果苷组(阳性对照).分别于中波紫外线(UVB)照射前、15 d后及30 d后,用Mexameter(R) MX 18检测豚鼠背部皮肤的黑素指数.连续治疗30 d后比较黑素指数、表皮内黑素细胞数目和黑素含量等指标.结果 UVB照射30 d时,豚鼠背部9块UVB照射区域的黑素指数显著高于照射前(P< 0.000 1).外涂1‰内皮素拮抗剂的照射区域30 d后的黑素指数值明显降低,和熊果苷组比较,差异有统计学意义(P< 0.000 1).内皮素拮抗组黑素含量指数1明显低于空白对照组(P<0.05).而3组间黑素含量指数2差异无统计学意义(P> 0.05).结论 外涂内皮素拮抗剂对UVB照射诱导豚鼠的色素沉着有一定治疗作用.  相似文献   
40.
We report the first detection of Senecavirus A (SVA ) in nine of 12 (75%) pigs in Thailand in 2016. The full‐length genome demonstrated that Thai SVA isolates were closely related to the first Canada strain (11‐55910‐3) than the recent strains causing outbreaks in Brazil, the United States and China in 2015–2016.  相似文献   
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