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31.
Objective To construct a eukaryotic expression system with pcDNA3-PfCSP/Hela for the Circ umsporozoite protein (CSP) gene of Plasmodium falciparum (P.falciparum), t o observe the immune responses in BALB/c mice induced by the expressed proteins .Methods The recombinant plasmid pcDNA3-PfCSP was transformed into the Hela cell line. The expressed protein was isolated and analyzed by using SDS-PAGE and used for immunization of BALB/c mice by subcutaneous, intravenous, and intraperitone al adminstration.Enzyme-linked immunosorbent assay(ELISA), Dot-ELISA, Wester n blot, T lymphocyte proliferation test, natural killer cell(NKC) activity assay , and CD4(+) and CD8(+) T cell detection were used for observation of humoral an d cellular immune responses.Results Immune sera strongly reacted with the expressed protein, antibody titer was up to 1∶6400 as detected by ELISA.Western blot analysis revealed a specific b and at 38.3 Kda.When the spleen cells of normal and immunized BALB/c mice we re specifically stimulated with expressed protein, the optical densities were 0 .12±0.03 and 0.34±0.04, respectively.The latter were significantly highe r than the former (P<0.01).We used the MTT colorimetric assay to measure NKC activity of mice spleen.The results showed that the NKC activity of immuni zed BALB/c mice was remarkably higher than that of the controls (P<0.05). CD4(+) and CD8(+) T cells were detected by using monoclonal antibody immunofluor escence methods.The results showed that the percentage of CD4(+) and CD8(+) T cells of immunized group were significantly higher than that of control group ( P<0.05).Conclusions The humoral and cell-mediated immune responses and elevated NKC activity to pr oducts made with a eukaryotic expression system could be specifically detected i n BALB/c mice.These findings indicate that the expressed protein could enhance the immune function in mice. 相似文献
32.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
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Lesions of the glenoid labrum can be associated with and cause shoulder instability and symptomatology by (1) allowing the shoulder to dislocate recurrently (anatomical instability); (2) allowing the shoulder to subluxate (anatomical instability); and (3) allowing the shoulder to click, catch, and lock secondary to partially attached fragments becoming interposed between the articular surfaces (functional instability). The latter two clinical entities are usually associated with "lesser" labral damage and diagnosis can be difficult. Six illustrative cases are presented and salient diagnostic and therapeutic points are discussed. The glenohumeral axillary arthrotomogram is presented as a sensitive diagnostic test for detecting labral lesions. 相似文献
35.
Sugar JA Kleinman A Heggenhougen K 《Health transition review : the cultural, social, and behavioural determinants of health》1991,1(2):211-220
Emphasis on the decline in mortality related to infectious disease, the improvement in child survival and the extension in longevity creates an optimistic view of the effects on health of social change. In contrast, attention to behavioural and social problems apparently stemming from current global social transformations leads to a more negative assessment. Specific historical processes shape local worlds of experience so as to yield complex patterns of social change with multiple outcomes. Study should be directed at the specific mediating social and moral processes that yield negative mental-health outcomes in order to develop international mental-health policy to guide prevention, and to control the dangerously destructive effects of specific social transformations, planned as well as unplanned. 相似文献
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E. Bruckheimer Z.R. Bulbul J.C. Love C.S. Kleinman W.E. Hellenbrand 《Pediatric cardiology》1998,19(5):428-430
Three patients with patent ductus arteriosus and moderate aortic stenosis had a marked reduction in aortic valve gradient
following transcatheter ductal occlusion. The hemodynamic effects of an aortopulmonary shunt on the severity of left ventricular
outflow obstruction and the implications on intervention are discussed. 相似文献
39.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg
TPA) protocols were found to be under multigenic control. Eighty- one N2
mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were
either solidly resistant (no papillomas) or highly susceptible (> or = 7
papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite
markers to check for associations with susceptible and resistant
phenotypes. A locus on Chr 5 (Skts4) was found to control the
susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to
papilloma formation. In addition, higher than expected linkage scores were
seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is
required to establish whether genes determining papilloma formation are
located in these regions of the genome. In general, no evidence was seen
for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in
17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.
相似文献
40.
PURPOSE: We tested the effect of molecular weight and amino acid composition (aspartate versus glutamate) in model peptides on calcium oxalate dihydrate (COD) formation to understand how known urinary inhibitor proteins might control spontaneous crystallization. MATERIALS AND METHODS: Supersaturated solutions of CaCl2 and Na2C2O4 in HEPES buffered saline solution were prepared at various calcium (Ca) to oxalate (Ox) ratios, but constant supersaturation, in the presence of protein inhibitors (polyaspartic acid molecular weight series or polyglutamic acid). The resulting crystals were collected and evaluated with optical microscopy. RESULTS: With no added inhibitors, the crystal size increased with Ca to Ox ratio, while the number of crystals decreased. With protein inhibitors at equivalent mass concentrations, intermediate molecular weight proteins produced a greater proportion of COD in Ca rich conditions than did either extreme. In Ox rich conditions, the proportion of COD was directly related to protein molecular weight. However, at equivalent molar concentrations, the proportion of COD produced was directly related to molecular weight under all conditions. Larger protein concentrations were required to produce COD at high Ox conditions, in proportion to the increased number of crystals produced. Polyglutamic acid had a much weaker effect on crystal structure, but it changed the COM morphology. CONCLUSIONS: The results suggest that a discrete number of protein molecules per crystal were required to direct crystallization toward COD, and that a characteristic size of polypeptide chain can be defined. The charge of the side group was not the sole determinant of this effect, as polyglutamic and polyaspartic acids behaved differently. Calcium oxalate crystal nucleation rates appeared to increase with Ox content. 相似文献