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1.
Summary It has been suggested that the immune system might figure prominently in the regulation of forelimb regeneration. However, neither the nature of this influence nor the aspect(s) of regeneration influenced are clearly known. The determination of which components of the immune system are indispensable for regeneration would be a logical first step in attempting to address such questions. This investigation, therefore, examined the effects of removing the spleen, a major lymphoid organ in the newt, upon the progress of regeneration. Splenectomies performed concomitantly with or after forelimb amputation failed to alter the time course of regeneration. Splenectomies, but not sham-splenectomies, performed prior to amputation reduced the time required to achieve successive stages of regeneration under some, but not all conditions, i.e., when performed 10–20 days before amputation, during the late fall and winter. Up until 35 days after amputation, no gross morphological distortions were observed as a result of splenectomy. It was concluded that the spleen is not required for regeneration to occur.Portions of this work constitute part of the thesis submitted by M.E. Fini in partial fulfillment of the requirements for the M.S. degree in Biology at Boston College  相似文献   
2.
The distribution of the extracellular matrix proteins types III pN-collagen and IV collagen, laminin and tenascin was investigated in fetal, infant, and adult human spleens by using immuno-electron microscopy. The presence of type III pN-collagen was assessed by using an antibody against the aminoterminal propeptide of type III procollagen. All the proteins other than type III pN-collagen were found in reticular fibers throughout development. In the white pulp of the fetus aged 16 gestational weeks, only an occasional type III pN-collagen-containing fibril was present, although type III pN-collagen was abundant in the reticular fibers of the red pulp. Conversely, in adults, most of the reticular fibers of the white pulp, but not of the red pulp, were immunoreactive for type III pN-collagen. Ring fibers, the basement membranes of venous sinuses, were well developed in both infant and adult spleens. The first signs of their formation could be seen as a discontinuous basement membrane, which was immunoreactive for type IV collagen, laminin, and tenascin in the fetus aged 20 gestational weeks. Intracytoplasmic immunoreactivity for all the proteins studied was visible in the mesenchymal cells of the fetus aged 16 gestational weeks and in the reticular cells of the older fetuses, which also showed labeling for type IV collagen and laminin in the endothelial cells. The results suggest that proteins of the extracellular matrix are produced by these stationary cells.  相似文献   
3.
The objective of this project was to conduct a feasibility study to determine whether the Brucella abortus S19 vaccine infects and persists in mice and determine whether S19 can be used as a challenge strain for vaccine trial studies. Groups of BALB/c mice were inoculated (intraperitoneally, subcutaneously, intranasally) and euthanized to determine colonization titers in the spleens and lungs. This study showed that S19 does infect and persist in the tissues of mice for 8 weeks and demonstrates that S19 can be used, safely and economically under BSL2 containment, as the challenge strain for future trials to evaluate vaccine efficacy.  相似文献   
4.
目的:探究脾脏保留手术对外伤性脾破裂患者免疫功能的影响。方法:选取2015年8月~2018年9月我院收治的外伤性脾破裂患者83例进行回顾性分析,根据手术方式不同分为两组,对照组(41例)患者给予脾脏切除术,观察组(42例)患者给予脾脏保留手术。比较两组患者的手术时间、术中出血量、下床活动时间、术后1d引流量、抢救成功率及治疗前后CD3~+、CD4~+、CD8~+和Tuftsin因子水平和并发症的发生情况。结果:治疗后,观察组患者的手术时间、术中出血量、术后下床时间和术后1d引流量均显著短于或低于对照组,而救治成功率显著高于对照组(P0.05)。两组患者治疗后的CD3~+、CD4~+和CD4~+/CD8~+水平均较治疗前显著下降,且观察组以上指标均显著高于对照组(P0.05)。对照组治疗后血清Tuftsin因子水平较治疗前显著下降,而观察组血清Tuftsin因子水平较治疗前显著升高,并显著高于对照组(P0.05)。观察组患者的总并发症发生率为7.14%,较对照组(24.39%)显著降低(P0.05)。结论:与脾脏切除术相比,脾脏保留手术可显著改善外伤性脾破裂患者的免疫功能,且手术效果更好,安全性更高。  相似文献   
5.
Study the effect of stachydrine hydrochloride to prostatic hyperplasia in mice which made of the urogenital sinus implantation. KM male mices were selected.The group was given the respective drugs for gavage, the group of BG and MG were given the distilled water which the same amount as the drugs group for 21 consecutive days. The level of DHT, ACP, Non PACP were measured in serum, the average wet weight of the prostate and prostate index were calculated, the expression of bFGF, EGF, IGF-I, TGF-β in prostate tissue were measured, the pathological changes of the prostate, kidney, thymus, spleen were observed by HE staining. Compared with MG, stachydrine hydrochloride high (SHH), medium (SHM) and low (SHL) group could reduced the level of DHT and PACP in serum significantly (P < 0.01); SHM and SHL could increased the express of TGF-β1 significantly (P < 0.05); SHH, SHM, SHL could reduced the express of EGF significantly (P < 0.01); SHM could reduced the express of IGF-Ⅰ significantly (P < 0.01); Compared with MG, SHH, SHM, SHL could reduced the pathological changes of prostate significantly (P < 0.01); FG could reduced the kidney pathological changes significantly (P < 0.01). Stachydrine hydrochloric had no significant effect on the kidney. Stachydrine hydrochloride had the effect of improve thymus, spleen pathological changes. Stachydrine hydrochloride has a good inhibition effect on prostatic hyperplasia model in mices.  相似文献   
6.
Several lectins, present in beans and edible plant products, have immuno-potentiating and anti-tumor activities. We here report the effects of garlic lectin purified from garlic bulbs on the production of cytokines such as interleukin-12 (IL-12) and interferon-γ (IFN-γ) in the mouse. Garlic lectin induced IFN-γ production in spleen cells in a bell-shaped time (24-60 h)- and concentration (0.25-2.0 mg/ml)-dependent manner. The maximal enhancement was observed at 36 h with 0.5 mg/ml of garlic lectin. The stimulatory effect of garlic lectin on IFN-γ production was completely inhibited by both actinomycin D and cycloheximide, an inhibitor of ribosomal protein synthesis and DNA-dependent RNA polymerase, respectively, and was associated with an increase in IFN-γ mRNA level. Garlic lectin also induced IL-12 production in mouse peritoneal macrophages in a concentration (0.25-1.0 mg/ml)- and bell-shaped time (3-24 h)-dependent manner. The lectin increased the phosphorylation of extracellular signal-regulated kinases (ERK) and p38 mitogen-activated protein kinase (p38 MAPK) in macrophages. Furthermore, specific pharmacological inhibitors of ERK kinase (U0126) and p38 MAPK (SB203580) also suppressed the production of IL-12 induced by garlic lectin. The present findings suggest that garlic lectin induces IL-12 production via activation of p38 MAPK and ERK in mouse macrophages, which, in turn, stimulates IFN-γ production through an increase in IFN-γ mRNA in the spleen cells.  相似文献   
7.
目的分析结核急性感染小鼠脾脏和肺脏的组织荷菌量以及病理的动态变化。方法以3×105CFU结核分枝杆菌标准株H37Rv尾静脉途径感染雌性C57BL/6J小鼠,测定感染后1 d、1周、2周、3周、4周、6周和8周肺脏及脾脏组织的荷菌量,脾脏和肺脏组织经HE染色分析病理变化。结果感染动物的脾脏荷菌量在前3周逐步提高,在4~8周脾脏荷菌量维持稳定,肺脏组织在2~8周组织荷菌量逐步升高。病理分析显示动物感染3周后肺脏和脾脏出现肉芽肿,在6~8周病理损伤加重。结论小鼠经尾静脉感染高剂量结核分枝杆菌在8周前表现为急性感染状态,适用于抗结核药物的体内药效学评价。  相似文献   
8.
目的观察脾虚型肠易激综合征(IBS)模型WHBE兔环核苷酸水平的变化。方法取WHBE兔和日本大耳白兔各18只,分别随机分成两组,即正常对照组6只,模型对照组12只,采用湿热应激加灌服番泻叶煎剂的方法造成脾虚证肠易激综合征(tBs)免模型,其中模型对照组造模后处理6只,剩余兔自然恢复10d,观察实验兔的血浆环核苷酸水平的变化。结果与正常对照组比较,WHBE兔模型对照组血浆cAMP和cGMP水平均显著升高(P〈0.05,P〈0.01),且自然恢复10d后血浆cAMP和cGMP水平仍高于正常对照组(P〈O.05,P〈O.01);日本大耳白兔模型对照组造模后及自然恢复10d后血浆cAMP和cGMP水平略有所升高,但差异均不显著(P〉O.05);且模型对照组和自然恢复组cAMP/cGMP比值均略低于正常对照组,但差异不显著(P〉O.05)。结论本实验脾虚证IBS模型兔的血浆环核苷酸水平随阴阳盛衰而变化,具有双重特点:既有阴虚特点,又有阳虚特点,且WHBE兔更适合于脾虚证IBS模型研究理想的实验动物。  相似文献   
9.
肉苁蓉多糖的促淋巴细胞增殖作用   总被引:1,自引:0,他引:1  
目的研究肉苁蓉多糖(CDPS)对小鼠淋巴细胞增殖的影响。方法MTT法检测小鼠脾淋巴细胞的增殖。环磷酰胺(Cy)复制免疫功能低下的动物模型,分别测定正常及免疫低下动物脾脏、胸腺指数。胸腺细胞增殖法测定白细胞介素-2(IL-2)活性。结果CDPS对丝裂原(ConA及LPS)活化淋巴细胞及未活化正常细胞均有明显促增殖作用,并促进淋巴细胞IL-2的分泌。腹腔给药显示CDPS具明显提高正常及免疫低下小鼠的脾指数,对因Cy所致胸腺指数的降低也有显著的对抗作用。结论CDPS可显著促进小鼠脾淋巴细胞增殖,该作用可能与其促IL-2分泌有关。  相似文献   
10.
林名瑞  陈怀宇  文丹  姚洁  李玮 《蛇志》2021,(1):23-27
目的采用Small RNA测序技术检测脓毒症小鼠24 h脾组织microRNA(miRNA)的表达变化,并从非编码基因层面分析脓毒症脾功能损伤的可能机制。方法将30只SPF级健康BALB/C小鼠随机分为对照组和脓毒症组,每组15只。脓毒症组采用LPS 10 mg/kg腹腔注射进行建模,对照组仅予等量生理盐水腹腔注射。两组术毕均行肌肉注射平衡液5 ml/kg,并于术后24 h各组随机取5只小鼠的脾组织提取RNA,采用Small RNA测序技术进行miRNA检测,然后应用生物信息学软件分析脓毒症小鼠脾组织的miRNA表达差异及靶基因预测。结果小鼠建模后24 h,与对照组相比,脓毒症小鼠脾脏组织已知及未知miRNA表达上调数分别为39个、3个,下调数分别为16个、3个。其中已知miRNA表达上、下调倍数最大的前5个基因分别为Rno-miR-217-5p,rno-mir-216a-5p,rnomiR-216b-5p,rno-miR-375-3p,rno-mir-216b-3p。下调倍数前5的miRNA:Rno-miR-138-5p,rno-miR-451a-3p,rno-miR-138-1-3p,rno-miR-202-5p,rno-miR-592。结论LPS诱导脓毒症小鼠可出现miRNA表达量的改变,其上、下调倍数最显著的miRNA可能对预测LPS诱导的脓毒症脾功能损伤有一定指导意义。  相似文献   
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