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91.
内皮素性大鼠门静脉高压模型的建立   总被引:1,自引:0,他引:1  
目的: 建立内皮素-1(ET-1)引起门静脉压力升高的动物模型。方法: 正常雄性SD大鼠48只,随机分为生理盐水组、ET-1低剂量组(0.3 μg/kg),ET-1中剂量组(1.0 μg/kg)和ET-1高剂量组(3.0 μg/kg)。生理盐水组大鼠经股静脉注入生理盐水,其余各组大鼠按相应剂量经股静脉注入ET-1溶液,观察门静脉压力和颈动脉压力的变化情况,并筛选出能使门静脉压力升高最适宜的剂量;另取15只大鼠随机分为对照组、ETAR阻断剂(BQ-123)组和ETBR阻断剂(BQ-788)组,实验开始前30 min经各组大鼠股静脉分别注入生理盐水、ETR阻断剂BQ-123(给药剂量为12.5 μg/kg)和BQ-788(给药剂量为15 μg/kg),然后以选定的适宜剂量匀速注入ET-1溶液,观察各组大鼠门静脉压力变化。结果: 不同剂量的ET-1均能使门静脉压力升高,尤以高剂量组最为明显;而提前注入ETR阻断剂之后,再注入ET-1溶液门静脉压力虽然升高,但升高的幅度较小。结论: 成功创建了内皮素性大鼠门静脉高压模型,此模型可用于研究ET-1在PHT发病机制中的作用和药物对PHT时血中ET-1的影响。  相似文献   
92.
INTRODUCTIONAdultRespiratoryDistressSyndrome(ARDS)isanacuteprogressiverespiratoryfailurecausedbymanyreasons.Thetherapeuticactionofthissyndromeisuncertain,becausethemechanismisnotwellknown.Thatis,theprognosisiscritical,themortailityisquiteheigh(50%f)ti--63'Butintherecenttenyears,manyscholarsinourcountryhavehadmuchexperienceintheaspectofusinganisodaminetorescueARDSpatientsandhavedecreasedthemortality(')'Howeveverthescholarsexplaintheprincipleofitindifferentways'Thechangesofmicrovascula…  相似文献   
93.
Proteoglycan-induced arthritis is a murine autoimmune model displaying many similarities to human rheumatoid arthritis and ankylosing spondylitis, as has been documented by clinical, immunological and histopathological studies. Since the onset of arthritis correlates with the serum antibody level to mouse cartilage proteoglycan (PG), it is believed that these autoreactivc antibodies may play crucial roles in the pathological mechanisms of PG-induced arthritis. We have found that fertility in these PG-induced arthritic mice had been reduced but, unlike collagen-induced arthritis, had not been completely lost. Moreover, pregnancy had a beneficial effect upon the clinical symptoms with very little or no influence on scrum antibody levels. Although fertility was retained and arthritic mothers delivered healthy offspring, the birth frequency was significantly less than in non-arthritic age-matched controls. Furthermore, the presence of anti-PG autoantibodies (predominantly IgG1 subclass) transmitted from arthritic mothers to infants transplacentally and by milk during the lactation period did not render these offspring either resistant or more sensitive to subsequent induction of arthritis. Subsequent immunization of infants with ‘arthritogenic’ PG revealed an unaltered susceptibility to arthritis induction.  相似文献   
94.
We studied the effects of local IL-10 application, introduced by a recombinant human type 5 adenovirus vector, in the mouse knee joint during the early phase of CIA. One intra-articular injection with the IL-10-expressing virus (Ad5E1mIL-10) caused substantial over-expression of IL-10 in the mouse knee joint, using virus dosages which did not induce distracting inflammation. High expression of IL-10 was noted for a few days, being maximal at day 1. One intra-articular injection of Ad5E1mIL-10 in the knee joints of collagen type II (CII)-immunized mice, before onset of CIA was noted, reduced the incidence of collagen arthritis in that knee. Of high interest, the protective effect of local IL-10 expression by Ad5E1mIL-10 was not restricted to the knee joint alone. The arthritis incidence in the ipsilateral paw was highly suppressed. In contrast, local IL-10 over-expression was not effective when treatment was started after onset of CIA. Further analysis in the acute streptococcal cell wall-induced arthritis model revealed that local IL-10 over-expression markedly suppressed the production of tumour necrosis factor-alpha (TNF-alpha) and IL-1alpha, but had no significant effect on IL-1beta and IL-12 production in the inflamed synovium. These data indicate that local over-expression of IL-10 in the knee joint of mice regulates the expression of collagen arthritis, probably through down-regulation of TNF-alpha.  相似文献   
95.
The antibody response of rabbits immunized with a total histone mixture containing randomly coiled H1/H5, H2A, H2B, H3 and H4 devoid of DNA was investigated in direct and competitive ELISA. The antisera were tested with isolated histones and chromatin and with a series of overlapping synthetic peptides covering the entire sequences of the four core histones and two peptides of H1. It was found that the New Zealand (NZ) white rabbits immunized with the total histone (TH) mixture complexed with RNA produced IgG antibodies reacting with histones and with a number of histone peptides but not with chromatin. The antisera also contained IgG antibodies which bound components that correspond to common target antigens in autoimmune diseases such as native dsDNA, peptides of Sm-D antigen, ubiquitin, branched peptides of ubiquitinated H2A and poly(ADP-ribose). By competition experiments, it was shown that these antibodies corresponded to non-crossreacting antibody populations. New Zealand rabbits immunized with TH in the absence of RNA or random outbred rabbits immunized with the RNA-complexed histone fraction produced antibodies reacting with histone, chromatin and very few histone peptides, while no activity with non-related antigens was observed. The pattern of reactivity of antisera raised in NZ rabbits with RNA-complexed TH was found to be very similar to that observed in sera of patients with systemic lupus erythematosus while, in contrast, the antibody response was very different in NZ or outbred rabbits immunized with various native nuclear particles and with individual histones. Altered nucleosome particles rather than native nucleosomes may represent the antigenic stimulus giving rise to autoantibodies.  相似文献   
96.
目的:建立能反应自身免疫特点的1型糖尿病动物模型,为进一步研究该病发病机理奠定基础。方法:将16只NOD.Scid小鼠随机分为两组,实验组小鼠腹腔注射发病NOD小鼠脾细胞,对照组注射未发病NOD小鼠脾细胞;每日测定血糖和体重;当出现重度糖尿病临床表现时处死,其余小鼠细胞过继后10周处死,经组织学观察和细胞因子ELISA测定。结果:实验组小鼠发病率为8/8,对照组为0/8;胰岛炎性积分分别为2.5±0.2,0;实验组IL-2、IL-10、IFN-γ水平分别为60.7pg/ml、15.5pg/ml、20.2ng/ml,对照组为2.4pg/ml、17.5pg/ml、3.2ng/ml。结论:在NOD.Scid小鼠体内一次性过继发病NOD小鼠脾细胞后5~10周可成功建立1型糖尿病的小鼠模型。  相似文献   
97.
Sera from eight rhesus monkeys that had been immunized with native bovine type II collagen were tested for antibodies to cyanogen bromide peptides (CB peptides) of type II collagen by Western blotting. The monkeys produced IgG antibodies to a number of different CB peptides, with five out of eight animals producing antibodies to the CB-11 peptide (four arthritic, one non-arthritic). Antibody epitopes on the CB-11 peptide of bovine type II collagen recognized by these sera were investigated by epitope mapping. Peptides (8-mers overlapping by seven amino acids) representing the CB-11 region were synthesised and the sera screened for binding to these peptides to determine areas of high IgG antibody binding to this region of type II collagen. The profiles obtained were not identical, though there were some epitopes that were commonly recognized. Antibodies to one epitope, also present in human type II collagen, were found only in the sera of two animals with the severest arthritis. The technique of epitope mapping has successfully identified a number of epitopes within the CB-11 peptide of type II collagen recognized by antibodies from bovine type II collagen-immunized monkeys. Studies on the relevance of responses to the identified epitopes can now be undertaken.  相似文献   
98.
The kinetics of serum viral responses and acute liver injury were studied during neonatal woodchuck hepatitis virus (WHV) infection in relation to the chronic or resolved outcome. The mean concentrations of serum WHV DNA and surface antigen were significantly higher by week 10 post infection in chronic infections compared to resolving infections, and diverged even further by the time of peak viral load development in serum (week 12). After week 12, these viral markers were detected less frequently with time and at lower concentrations in the resolved outcome. In both outcomes, mean serum activities of hepatic enzymes became increased significantly above baseline by weeks 10-12, peaked at week 14, and normalized by weeks 20-22, thus indicating transient acute liver injury. The increasing liver injury responses were comparable between outcomes at week 12, when serum viral load was markedly higher in the developing chronic infections. This suggested a deficiency in early non-cytolytic control of infection in the chronic outcome. At week 14, liver injury was significantly greater in the resolved outcome and associated with higher mean Fas ligand (FasL) and perforin messenger RNAs (mRNAs) in liver compared to the chronic outcome. This indicated greater immune-mediated killing of infected hepatocytes during resolution. Thus, chronicity as an outcome of neonatal WHV infection develops relatively early during the acute phase of infection due to reduced immune-mediated clearance of infected hepatocytes by both cytolytic and non-cytolytic processes.  相似文献   
99.
Sensitization and exposure to house-dust-mite allergens is an important cause of asthma. Standardized, reliable, and reproducible methods for measuring exposure are essential for the assessment of the relationship between exposure, sensitization, and asthma. This study investigated the variability of the house-dust-mite allergen Der p 1 concentration in reservoir dust collected within whole carpets in living rooms and bedrooms. The carpets of nine bedrooms and 11 living rooms were sampled. Each room was divided into 1 m2 areas measured from wall to wall where the carpet was accessible. Reservoir dust samples were collected by vacuuming each 1 m2 area for 2 min. Der p 1 was assayed by a two-site monoclonal-antibody-based immunometric ELISA. Der p 1 was detectable in the carpets of nine bedrooms and six of the 11 living rooms. Within these 15 rooms, there was a wide range of Der p 1 levels. The smallest range of allergen within single room was 0.9 μg Der p 1/g dust (0.2 and 1.1 ng/g; 5.5-fold difference), and the largest was 149.2 μg Der p 1/g dust (0.8 and 150 μg/g; 192-fold difference). The mean range of allergen levels in the living rooms was 11.5 jig Der p 1/g of dust, and the mean coefficient of variation of these rooms was 80.2%. illustrating the huge variation of mite allergen levels within each room. The variation within bedrooms was also large, with a mean coefficient of variation value of 88.7%. The coefficient of variation was significantly lower around soft furnishings or beds (57%) than in the rest the room (89.3%), with the mean difference being 32% (95% CI 27ndash;63%; P=0.04). In conclusion, this study has shown that there is a great variation of Der p 1 levels between areas within a room. No consistent pattern of distribution of mite allergen within a room was found. Der p 1 levels in areas around soft furnishings and beds varied less than the levels in the rest of room.  相似文献   
100.
目的 :研究不同剂量加味保元汤对束缚应激小鼠非特异性免疫功能的影响。方法 :80只小鼠随机等分为加味保元汤 5g/kg体重、 10g/kg体重、15g/kg体重和应激组 ,用巨噬细胞体内吞噬法 ,测其吞噬率及吞噬指数。结果 :吞噬指数 :10g/kg体重组明显高于 15g/kg体重组 (P <0 0 5 ) ,10g/kg体重组与 5g/kg体重组比较虽P >0 0 5 ,但均值高于 5g/kg体重组 ;吞噬率 :10g/kg体重组最高。结论 :10g/kg体重剂量加味保元汤对束缚应激小鼠非特异性免疫功能保护作用效果最佳。  相似文献   
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