首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 156 毫秒
1.
采用组织切片和免疫组化技术对大口黑鲈的胰腺进行了组织学观察。经H-E染色和G-醛复红染色了的切片显示:大口黑鲈腹腔中10多个肉眼可见的黄白色颗粒物其实是被一层结缔组织和外分泌胰腺包裹着的胰岛结构,其中最大的一个即为主岛;还有许多肉眼不可见的胰岛结构被埋藏于总胆管的管壁中;肝脏中有外分泌胰腺的存在与分布。过氧化物酶标记的链霉卵白素免疫组化切片和图像分析显示:B细胞主要集中胰岛的中央区;A细胞分布于胰岛的全部。本研究的结论为:大口黑鲈的内分泌胰腺主要分布于总胆管周围,外分泌胰腺除了包裹于胰岛之外也分布于肝脏中,胰腺的分布属于弥散型。  相似文献   

2.
Diabetic complications such as neuropathy, retinopathy, and renal and cardiovascular disease continue to pose major health risks for diabetic patients. Consequently, much effort has focused on approaches that could replace conventional insulin therapy and provide more precise regulation of blood glucose levels. The biohybrid perfused artificial pancreas was designed to incorporate islet tissue and a selectively permeable membrane that isolates this tissue from the immune system of the recipient. Biohybrid pancreas devices containing canine islet allografts were implanted in ten pancreatectomized dogs requiring 18 to 32 units of injected insulin daily. These implants resulted in good control of fasting glucose levels in six of these animals without further exogenous insulin for periods of up to 5 months.  相似文献   

3.
Pancreatectomy in the eel causes a slight tendency toward hyperglycemia; total and partial pancreatectomies cause a drop of total serum cholesterol. Thus, complete removal of the islet tissue in this teleost is not followed by diabetes mellitus, and also the endocrine control of the cholesterol-containing serum components seems to differ from that in mammals.  相似文献   

4.
The addition of glucose stimulated release of insulin from the isolated islet tissue of the toadfish incubated in vitro. Reduced nicotinamide-adenine dinucleotide also stimulated insulin release, whereas the oxidized form had no effect. Both oxidized and reduced nicotinamide-adenine dinucleatide phosphate stimulated insulin release, but the reduced form was significantly more effective.  相似文献   

5.
The application of isolated pancreatic islet transplantation for treatment of diabetes mellitus has been hampered by the vulnerability of islet allografts to immunologic rejection. Rat islet allografts that were transplanted into the thymus of recipients treated with a single injection of anti-lymphocyte serum survived indefinitely. A state of donor-specific unresponsiveness was achieved that permitted survival of a second donor strain islet allograft transplanted to an extrathymic site. Maturation of T cell precursors in a thymic microenvironment that is harboring foreign alloantigen may induce the selective unresponsiveness. This model provides an approach for pancreatic islet transplantation and a potential strategy for specific modification of the peripheral immune repertoire.  相似文献   

6.
Insulin biosynthesis: evidence for a precursor   总被引:48,自引:0,他引:48  
Human islet cell tumor tissue and isolated islets of Langerhans from rats incorporated radioactive amino acids in vitro into insulin and a larger acid-alcohol soluble protein which could be separated from insulin by gel filtration. The amino acids were incorporated into the larger protein earlier than into insulin; only after incubation of islets for approximately 30 minutes did radioactivity begin to appear in insulin. The transfer of about 70 percent of the radioactivity of the larger protein to insulin was demonstrated in the absence of new peptide bond synthesis (cycloheximide), or during incubation with unlabeled amino acid (chase). The results indicate that the larger protein is a precursor in the biosynthesis of insulin. The name "proinsulin" is suggested for this protein.  相似文献   

7.
H-2 antigen class: effect on mouse islet allograft rejection   总被引:5,自引:0,他引:5  
Rejection of mouse pancreatic islet allografts occurred in a high percentage of donor recipient combinations identical for H-21-region antigens and differing at H-2K and H-2K + H-2D without I-region disparities. The results suggest that disparities in major histocompatibility complex antigens of class I (H-2K and H-2D) alone are capable of eliciting islet allograft rejection, and that lack of a stimulus from class II (I-region) alloantigens does not ensure permanent islet allograft survival.  相似文献   

8.
9.
成年皖西白鹅母鹅消化腺的形态学观察   总被引:1,自引:0,他引:1  
研究了成年皖西白鹅母鹅消化腺的形态特征。结果表明 :成年皖西白鹅母鹅消化腺由唾液腺、肝脏和胰腺组成。肝脏的组织结构由肝小叶和门管区构成 ,肝小叶由中央静脉、肝细胞管和肝窦组成 ,门管区包括小叶间胆管、小叶间动脉和小叶间静脉 ,还有淋巴组织分布。胰腺包括外分泌部和内分泌部 ,外分泌部由腺泡和导管组成 ,内分泌部为一细胞团 ,即胰岛。  相似文献   

10.
Type 1 diabetes mellitus results from the autoimmune destruction of the beta cells of the pancreatic islets of Langerhans and is recapitulated in the nonobese diabetic strain of mice. In an attempt to rescue islet loss, diabetic mice were made normoglycemic by islet transplantation and immunization with Freund's complete adjuvant along with multiple injections of allogeneic male splenocytes. This treatment allowed for survival of transplanted islets and recovery of endogenous beta cell function in a proportion of mice, but with no evidence for allogeneic splenocyte-derived differentiation of new islet beta cells. Control of the autoimmune disease at a crucial time in diabetogenesis can result in recovery of beta cell function.  相似文献   

11.
12.
Hatchling green iguanas (Iguana iguana) emerge from the ground in small groups in a communal nesting area on a small Panamanian islet and engage in complex social interactions. Iguanas from different clutches often join together before and during departure from the nest site. They also usually move around the islet and migrate from it to the larger adjacent landmass in social groups. These and other observations indicate that the sophistication of saurian social organization and neonate behavior has been underestimated.  相似文献   

13.
Solid tumors depend on angiogenesis for their growth. In a transgenic mouse model of pancreatic islet cell carcinogenesis (RIP1-Tag2), an angiogenic switch occurs in premalignant lesions, and angiogenesis persists during progression to expansive solid tumors and invasive carcinomas. RIP1-Tag2 mice were treated so as to compare the effects of four angiogenesis inhibitors at three distinct stages of disease progression. AGM-1470, angiostatin, BB-94, and endostatin each produced distinct efficacy profiles in trials aimed at preventing the angiogenic switch in premalignant lesions, intervening in the rapid expansion of small tumors, or inducing the regression of large end-stage cancers. Thus, anti-angiogenic drugs may prove most efficacious when they are targeted to specific stages of cancer.  相似文献   

14.
为了研究三氯化铬与大鼠胰岛细胞共培养对胰岛细胞活性与胰岛素分泌水平的影响,并对其影响机制进行探讨,以台盼蓝染色法和MTT法检测胰岛β细胞活性,以不同浓度葡萄糖刺激胰岛素释放评价三氯化铬对胰岛细胞功能的影响,同时以RT-PCR检测胰岛细胞的抗凋亡基因bcl-2的表达。结果发现,随培养液中三氯化铬浓度的增加,胰岛活性随之增加,凋亡率降低,但2.0μmol/L的活性有所降低,凋亡率与对照组没有显著差异(P>0.05)。低糖和高糖浓度环境中试验组与对照组的胰岛素分泌没有显著差异(P<0.05),RT-PCR发现试验组的bcl-2表达显著高于对照组(P<0.05)。2.0μmol/L CrCl3明显降低胰岛细胞的凋亡率,提高其存活率,改善胰岛功能。  相似文献   

15.
Faustman DL  Tran SD  Kodama S  Lodde BM  Szalayova I  Key S  Toth ZE  Mezey E 《Science (New York, N.Y.)》2006,314(5803):1243; author reply 1243
Chong et al., Nishio et al., and Suri et al. (Reports, 24 March 2006, pp. 1774, 1775, and 1778) confirmed that treating nonobese diabetic (NOD) mice with an immune adjuvant and semisyngenic spleen cells can reverse the disease but found that spleen cells did not contribute to the observed recovery of pancreatic islets. We show that islet regeneration predominately originates from endogenous cells but that introduced spleen cells can also contribute to islet recovery.  相似文献   

16.
1993年中国对虾暴发性流行病细菌病原学研究   总被引:13,自引:0,他引:13  
1993年中国对虾发生了暴发性流行病。自病虾体内分离出多株细菌,主要是弧菌属和微球菌属。感染实验表明弧菌毒力强,球菌毒力相对弱。未除菌病虾组织浆悬液组比除菌病虾组织浆悬液组死亡快,证明细菌尤其是弧菌可加速暴发性流行病病虾的死亡,16种不同药物敏感试验结果表明细菌对目前常用抗生素敏感性显降低。  相似文献   

17.
18.
白洋淀分散鸭养殖产生的污染物是导致其水体污染的主要来源之一。依据“减量化、就地处置资源化、养分循环”思路,提出湖心岛分散鸭养殖污染控制模式,主要包括:鸭粪收集系统(收集网、径流和冲洗水收集沟)、鸭粪沼气发酵与利用系统、沼液湿地净化和沼渣利用系统。选择安新县安新镇王家寨村占地5 000 m2养殖1 500只鸭的湖心岛建立综合控制示范工程。2010年4~11月,示范工程在典型降雨日和非降雨日排水的COD、总氮、总磷分别为351 mg/L、74.2 mg/L、7.1 mg/L和214 mg/L、42.1 mg/L、5.3 mg/L,水质符合《畜禽养殖业污染物排放标准》(GB 18596-2001);这是由于源头收集系统收集了陆上活动区40%的鸭粪,同时末端处理系统(沉淀池+人工湿地)对养鸭废水污染物的高效削减。沼气池产生的沼气和剩余的沼液沼渣可以作为能源和肥料加以利用。本文集成湖心岛分散鸭养殖污染控制模式简便、适用,具有推广价值。  相似文献   

19.
目的建立乳腺癌个体化疗体系,减少滥用药物或过度用药给患者带来的副作用,提高化疗药物的有效率.方法分离、培养乳腺癌患者新鲜组织细胞,加入临床常用化疗药物,体外培养一定时间后,按ATP—TCA试剂盒说明书进行细胞ATP含量检测,根据荧光强度计算药物半数致死量及细胞生长增殖抑制率;提取切除的手术标本及癌旁组织RNA,RT—PCR,检测MDR基因表达水平;根据细胞敏感程度及MDR基因水平检测优化对患者的化疗方案.结果142例患者对常见的化疗药物敏感程度各有不同;在这些耐受病例中约有50%-80%病例MDR基因高表达.结论ATP—TCA配合MDR基因水平检测有利于建立个体化化疗体系,提高临床化疗药物的有效性.  相似文献   

20.
白洋淀分散鸭养殖产生的污染物是导致其水体污染的主要来源之一。依据"减量化、就地处置资源化、养分循环"思路,提出湖心岛分散鸭养殖污染控制模式,主要包括:鸭粪收集系统(收集网、径流和冲洗水收集沟)、鸭粪沼气发酵与利用系统、沼液湿地净化和沼渣利用系统。选择安新县安新镇王家寨村占地5 000 m2养殖1 500只鸭的湖心岛建立综合控制示范工程。2010年4~11月,示范工程在典型降雨日和非降雨日排水的COD、总氮、总磷分别为351 mg/L、74.2 mg/L、7.1 mg/L和214 mg/L、42.1 mg/L、5.3 mg/L,水质符合《畜禽养殖业污染物排放标准》(GB 18596-2001);这是由于源头收集系统收集了陆上活动区40%的鸭粪,同时末端处理系统(沉淀池+人工湿地)对养鸭废水污染物的高效削减。沼气池产生的沼气和剩余的沼液沼渣可以作为能源和肥料加以利用。本文集成湖心岛分散鸭养殖污染控制模式简便、适用,具有推广价值。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号