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1.
目的通过硫代乙酰胺(TAA,300mg·kg^-1·d^-1)不同用药时间诱导A型肝性脑病,比较大鼠的行为学、生物化学以及组织学改变,探讨造模最适时间。方法将大鼠分为A、B、C、D四组,其中A组为正常对照组;B、C、Di组用TAA(300mg·kg^-1·d^-1)分别连续灌胃2d、3d、4d,A组用相等量生理盐水灌胃4d。比较各组大鼠行为学变化、脑功能评分、AHE的诱导率和致死率,并分析各组给药结束24h后血氨、ALT、AST、TBIL的差异。结果C、D组比B组大鼠脑功能评分高,差异有统计学意义(P〈0.0083);C、D组比B组诱导率高(P〈0.0083),而D组比B、C组的大鼠致死率高,差异有统计学意义(P〈0.0083);C、D组血氨及ALT、AST、TBIL肝功能指标比B组高,差异有统计学意义(P〈0.0083);C、D组TAA用药后肝组织学观察炎症浸润、坏死、纤维化等损害最明显。结论300mg·kg^-1·d^-1的TAA连续灌胃3d,行为学改变显著.致死率较低.血氨较高.肝功能损害明显.为TAA诱导大鼠急性肝性脑病适宜时间。  相似文献   

2.
目的观察绿茶多酚(GTPs)对帕金森病(PD)小鼠脊髓前角星形胶质细胞过度活化的影响,并探讨其机制。方法将45只C57BL/6J小鼠随机分为3组各15只。模型组及预防组以1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)腹腔注射7d,30mg/(kg·d),但预防组于模型制备前3个月开始GTPs干预,至注射MPTP结束;正常组连续7d腹腔注射同体积生理盐水,饮水中未加入GTPs,余处理方法及时长均与上述两组相同。采用免疫组化法对脊髓进行染色,光镜下观察脊髓胶质原纤维酸性蛋白(GFAP)阳性细胞变化,计数GFAP阳性细胞个数;电镜下观察各组星形胶质细胞变化;比色法检测超氧化物歧化酶(SOD)、丙二醛(MDA)水平。结果3组GFAP阳性细胞形态无明显差异。与正常组及预防组比较,模型组颈膨大、腰膨大GFAP阳性细胞数增加(P均〈0.01)。模型组出现较多活化的星形胶质细胞,增生、肥大,常成群分布,细胞胞体、胞核增大,胞质丰富,其内细胞器增多;预防组及正常组活化的星形胶质细胞较少。与正常组比较,模型组颈膨大、腰膨大SOD水平降低,MDA水平升高;与模型组比较,预防组颈膨大、腰膨大SOD水平升高,MDA水平降低(P均〈0.01)。结论GTPs能缓解PD脊髓前角星形胶质细胞过度活化,其机制可能为降低脊髓前角氧化应激水平。  相似文献   

3.
[目的]观察电针对糖尿病胃轻瘫(DGP)大鼠胃电活动与延髓迷走孤束复合体(VSC)内神经元和星状胶质细胞可塑性变化的影响。[方法]实验大鼠分为空白对照(空白)组、DGP模型(模型)组、模型加电针足三里穴(足三里)组和模型加电针三阴交穴(三阴交)组。模型制备采用腹腔注射5%四氧嘧啶和熟地灌胃诱导的方法。实验3周后记录大鼠的胃电活动,取延髓进行抗Fos蛋白和抗胶质原纤维酸性蛋白(GFAP)的免疫组化染色。[结果]与空白组比较,模型组的胃电平均频率和振幅明显降低。而足三里组和三阴交组的平均频率和振幅较模型组明显升高(P〈O.01,〈0.05);以足三里组升高更明显,与三阴交组比较差异有统计学意义(P〈0.05)。除空白组外,Fos阳性神经元、GFAP阳性星状胶质细胞集中表达于VSC。以模型组的Fos和GFAP表达最高,而足三里组与三阴交组的表达较模型组明显减少,且它们之间差异有统计学意义(P〈0.01)。[结论]针刺可改善糖尿病胃运动功能障碍,延髓VSC内免疫阳性神经元和胶质细胞可能参与了此调节作用。  相似文献   

4.
促红细胞生成素对星形胶质细胞损伤的保护作用   总被引:1,自引:0,他引:1  
目的探讨促红细胞生成素(EPO)对体外培养的星形胶质细胞的作用。方法采用出生3 d内的SD大鼠大脑制成细胞悬液后,在含15%胎牛血清的DMEM培养液中培养,通过摇床和逐渐传代纯化星形胶质细胞,分为正常组、正常E组(正常细胞+EPO 10 U/L)、损伤组(缺氧3 h)、损伤E组(损伤细胞+EPO 10 U/L)。用免疫荧光技术鉴定星形胶质细胞,MTT法检测细胞活性和凋亡情况,PCR技术测定细胞纤维酸性蛋白(GFAP)。结果星形胶质细胞摇床后传至第3代,经鉴定其星形胶质细胞纯度达95%以上;缺营养3 h后部分细胞形态变圆甚至死亡,漂浮在正常细胞表面;正常E组和损伤E组细胞在分别加入EPO 3 d后,损伤E组细胞活性与GFAP表达均明显升高,正常E组则没有明显变化。结论EPO对缺营养损伤的星形胶质细胞有显著的保护作用,而对正常星形胶质细胞无保护作用。  相似文献   

5.
目的探讨血脑屏障破坏程度与癫痫发作之间的关系。方法将62只SD大鼠按饲养时间随机分为空白对照组、模型对照组和甘露醇应用组,通过建立自由落体损伤模型分析外伤性大鼠血脑屏障破坏程度与癫痫发作以及和胶质细胞增生情况的关系。结果甘露醇应用组与模型对照组血脑屏障开放程度比较,差异有统计学意义(P〈0.01);甘露醇应用组与模型对照组癫痫发作的大鼠数量比较,差异无统计学意义(P〉0.05);甘露醇组与模型对照组GFAP阳性细胞数比较差异有统计学意义(P〈0.01)。结论血脑屏障破坏后引起血清白蛋白外渗到脑组织,血清白蛋白通过转化生长因子p受体被胶质细胞摄取引起胶质细胞激活和增生,血脑屏障开放程度越大,胶质细胞增生越明显,激活的星形胶质细胞神经兴奋性增高,最终引发癫痫发作。  相似文献   

6.
胰性脑病是急性胰腺炎的重要并发症,其临床发生率为3%~27%,而死亡率高达40%以上。血脑屏障是中枢神经系统(CNS)的重要保护机制,它能保护大脑免受外周致病因子的攻击。血脑屏障的损伤和通透性升高是多种CNS炎症及病变的前提。胶质纤维酸性蛋白(GFAP)是星形胶质细胞的标志蛋白,由各种原因引起的CNS损伤均可引起星形胶质细胞活化、GFAP表达增加,因此GFAP表达水平可以作为CNS损伤程度的标志。  相似文献   

7.
目的观察羟基红花黄色素A(HSYA)对脑缺血-再灌注大鼠星形胶质细胞活性的影响。方法将健康成年雄性SD大鼠12只随机分为HSYA组和对照组,每组6只。应用线栓法制备大鼠大脑中动脉缺血1.5h再灌注72h模型。成功阻断大脑中动脉血流后,HSYA组于缺血后30min,再灌注即刻,再灌注后24及48h分别经尾静脉注射HSYA,每次2mg/kg。对照组给予同体积的等渗盐水,其余与HSYA组相同。采用免疫组化染色和Western blot检测方法,观察HSYA对脑缺血后缺血半暗带区和核心区星形胶质细胞活化的标志物——胶质纤维酸性蛋白(GFAP)的影响。结果免疫组化染色显示,与对照组比较,HSYA组半暗带区GFAP阳性细胞数目增加,细胞突起增多、粗大,荧光染色强度增加(44±11比107±9),P〈0.05;WesternBlot检测显示,GFAP蛋白水平亦高于对照组[(100%比(127±7)%,P〈0.05]。但免疫组化染色和WesternBlot检测结果显示,HSYA对缺血核心区GFAP阳性细胞荧光染色强度(36.5±5.4比42.0±1.9)、GFAP蛋白水平[100%比(105±13)%]均没有显著影响,均P〉0.05。结论活血化瘀中药HSYA可以增加脑缺血-再灌注大鼠缺血半暗带区星形胶质细胞的活性。  相似文献   

8.
[目的]观察四逆泻心汤(SNXX)对慢性乙酸胃溃疡大鼠溃疡愈合的影响。[方法]SD大鼠40只,随机取10只作空白对照(A)组,行假手术处理,剩余大鼠用乙酸腐蚀法制慢性胃溃疡模型,造模后存活大鼠随机分为模型对照(B)组,SNXX治疗(C)组,雷尼替丁治疗(D)组。治疗3周后,测量溃疡体积、面积;光镜下评价溃疡愈合质量(QOUH),测定血清一氧化氮(NO)、表皮生长因子(EGF)水平。[结果]C组溃疡体积缩小优于B组(P〈0.01)、D组(P〈0.05);D组溃疡面积缩小优于B组(P〈0.01),C组溃疡面积较B组有缩小趋势,但无统计学意义。C组光镜下QOUH优于B、D组;血清NO水平低于B组(P〈0.01)、D组(P〈0.05);血清EGF水平高于A组(P〈0.01)、B组(P〈0.05),较D组有升高趋势,但无统计学意义。[结论]SNXX可促进大鼠慢性乙酸胃溃疡愈合,溃疡体积缩小及QOUH明显优于雷尼替丁,溃疡面积缩小与雷尼替丁的差异无统计学意义,降低NO水平,升高EGF水平可能为其机制之一。  相似文献   

9.
目的:探讨全反式维甲酸( ATRA)对星形胶质细胞清除淀粉样蛋白( Aβ)的影响及其机制。方法原代培养星形胶质细胞,使用Aβ42诱导原代星形胶质细胞凋亡,分别加入0.01、0.1、1、10μmol/L ATRA进行干预。采用MTT法检测细胞存活率,ELISA法检测培养基和细胞内Aβ42含量,Western blot 法检测APOE、BACE1表达变化。结果不同浓度的ATRA对Aβ42诱导的星形胶质细胞凋亡作用不同,其中0.1、1μmol/L可以显著抑制Aβ42诱导的星形胶质细胞凋亡(P<0.05)。细胞外培养基中Aβ含量、细胞内Aβ含量均明显下降(P均<0.01)。实验组APOE表达上调(P<0.01),BACE1表达无明显变化。结论 ATRA可以上调APOE表达,促进星形胶质细胞清除Aβ;低浓度ATRA对星形胶质细胞有保护性作用。  相似文献   

10.
目的探讨阿魏酸钠对大鼠前脑缺血再灌注(I/R)后白质胶质纤维酸性蛋白表达的影响。方法双侧颈总动脉夹闭法制备大鼠前脑I/R模型。雄性Wistar大鼠45只,随机分为假手术组(n=15),I/R组(n=15),I/R阿魏酸钠治疗组(n=15),每组按I/R2、4、6w3个时间点再分为3组(n=5)。模型制备免疫组化法检测I/R后2、4、6w胼胝体、内囊和脑室周围GFAP的表达。结果I/R后胼胝体、内囊和脑室周围GFAP的表达随时间延长逐渐增多,阿魏酸钠治疗组GFAP的表达较假手术组多,较缺血再灌注组减少,6w差异最显著(P〈0.05)。结论大鼠前脑缺血再灌注后白质GFAP表达增多,阿魏酸钠对脑白质缺血性损伤具有保护作用,其机制可能与调节星形胶质细胞活化状态,减轻内皮素对血管损伤有关。  相似文献   

11.
目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤,因其临床表现多样,导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用,拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点,以期有助于提高影像学的诊断准确率和降低漏诊率,尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料,检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例,通过查阅病例的方法,提取出胰岛素瘤的大小和解剖分布等数据,进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例,其中,男45例、女71例,年龄13~76岁,平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布:头颈部46例(39.7%),单发45例、多发1例;体尾部68例(58.6%),单发65例、多发3例;全胰腺多发2例(1.7%)。病变大小特点:最大径0.4~3.4 cm,平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例,≤3 cm 15例,>3 cm 3例。年龄与肿瘤的大小相关,≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm,P<0.05。头颈部的肿瘤大于体尾部的肿瘤,头颈部肿瘤平均大小(1.66±0.63)cm,体尾部(1.42±0.52)cm,P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发;绝大多数单发,但可以全胰腺多发;多数小于1.5 cm,肿瘤的大小与患者年龄和肿瘤的解剖分布相关。  相似文献   

12.
Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.  相似文献   

13.
Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.  相似文献   

14.
BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.  相似文献   

15.
血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。  相似文献   

16.
目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。  相似文献   

17.
氯硝柳胺悬浮剂的毒性评价   总被引:2,自引:2,他引:2  
目的评价氯硝柳胺悬浮剂的毒性,为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg,经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3,该药经口、经皮肤、经呼吸道毒性均属微毒类药物;兔眼用药后,观察期内无不良反应,对眼无刺激性;皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比,氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物,对鱼的毒性低于其乙醇胺盐可湿性粉剂,适合于现场应用。  相似文献   

18.
The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002  相似文献   

19.

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl−1•min−1 (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl−1•min−1 (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.  相似文献   

20.
The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H2-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.  相似文献   

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