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81.
墨旱莲乙酸乙酯总提物对T淋巴细胞功能的调节 总被引:6,自引:0,他引:6
目的 观察墨旱莲乙酸乙酯总提物(EAEEP)对T淋巴细胞介导的细胞免疫的影响。方法 采用正常小鼠及腹腔注射环磷酰胺造成免疫功能低下小鼠模型,观察EAEEP对外周血CD4^ ,CD8^ T淋巴细胞亚群比例、迟发性超敏反应(DTH)、ComA刺激的淋巴细胞平殖反应的影响。结果 EAEEP显著抑制正常小鼠的细胞免疫功能(正常组CD4^ T淋巴细胞比例为40.13%,EAEEP大剂量组降至30.87%),而对于免疫功能低下模型鼠可显著促进细胞免疫功能(使免疫抑制组CD4^ T淋巴细胞比例由34.87%升至40.80%)。结论 墨旱莲乙酸乙酯总提物对T淋巴细胞介导的细胞免疫具有一定的免疫调节作用。 相似文献
82.
目的 :检测周围神经损伤后免疫系统的变化。方法 :用 MTT法检测了坐骨神经损伤 1 ,2 ,5,7和 1 4d的大鼠脾细胞 NK活性及淋巴细胞转化功能 ,并用 PEG沉淀法检测了大鼠血清中循环免疫复合物 (CIC)的含量。结果 :坐骨神经损伤后 7和 1 4d大鼠脾细胞的自发转化率较对照组 (同样手术应激但无坐骨神经损伤 )略有增高 ;循环免疫复合物的含量术后 7d明显增高 ,1 4d时增加明显 ;而 NK活性则无明显变化 ,后期变化如何尚待进一步研究。结论 :周围神经损伤后 ,机体发生了免疫变化。 相似文献
83.
目的探讨残胃贲门癌手术切除,消化道重建的方法。方法总结1989年8月至1999年12月12例残胃贲门癌切除、空肠“9”字袢代胃及幽门重建术的治疗经验。结果无手术死亡,无倾倒综合征,无返流性食管炎。钡剂在“9”字环内有循环,下方重建凼门处有钡荆停留。全组均随访,随访时间最长4年3个月,最短4个月。其中1年内死亡2例,1~2年死亡4例,2~3年死亡2例,另4例生活良好。结论术后并发症少,有抗返流作用,利于营养支持,病人生活质量较高。 相似文献
84.
Heinz D. Osiewacz 《Current genetics》1994,26(1):87-90
A shuttle cosmid vector, pANsCos1, has been constructed for Escherichia coli and filamentous fungi. This vector contains two cos sequences separated by a single XbaI restriction site. pANsCos1 allows the efficient construction of representative genomic libraries from as little as 15–20 g of genomic DNA. Due to the presence of a functional hygromycin B phosphotransferase gene (hph) transformation of fungal protoplasts with pANsCos1, or derivatives of it, results in the formation of hygromycin B-resistant transformants. The T7 and T3 RNA polymerase promoter sequences flanking the cloning site, in combination with two adjacent NotI sites facilitate genomic walking and the rapid construction of restriction maps of cloned inserts.Dedicated to Professor Dr. K. Esser on the occasion of his 70th birthday 相似文献
85.
M. Di Rocco F. Callea B. Pollice M. Faraci F. Campiani C. Borrone 《European journal of pediatrics》1995,154(10):835-839
We report on five patients from three families with neurogenic arthrogryposis, cholestasis and tubular renal dysfunction. Despite a similar clinical picture the liver histology showed a broad pathological spectrum, ranging from pigment storage to parenchymal giant cell transformation and ductopenia. The findings are compared with those of other cases from the literature in search of a correct nosology of the syndrome characterized by arthrogryposis, renal and liver disease.Conclusion We propose to consider the picture of arthrogryposis, renal tubular dysfunction and cholestasis as a single syndrome. 相似文献
86.
R. J. Gouka J. G. M. Hessing H. Stam W. Musters C. A. M. J. J. van den Hondel 《Current genetics》1995,27(6):536-540
A homologous gene transfer system for Aspergillus awamori for site-specific integration is described, based on two components. First, a defined A. awamori pyrG mutant strain constructed by a selection strategy for gene-replacement in fungi. Second, a vector with a homologous pyrG selection marker containing a defined mutation at a site different from that of the mutations in the pyrG gene of the defined mutant strain. Defined mutation in the A. awamori pyrG gene, isolated from a genomic library by heterologous hybridisation with the A. niger pyrG gene as a probe, were introduced by specifically altering sequences at restriction sites in the coding region of the gene. After transformation of the A. awamori wild-type strain with vectors containing these mutated pyrG genes, and selection for 5-fluoro-orotic acid resistance (5-FOAR), on the average 60% of the 5-FOAR colonies originated from replacement of the wild-type pyrG gene by the mutated pyrG allele. After transformation of a mutant strain, carrying a mutation near the 5 end of the pyrG gene with vectors containing a mutation near the 3 end of the pyrG gene, 35% of the resulting transformants contained one copy of the vector at the pyrG locus. 相似文献
87.
O. Popanda G. Fox H. W. Thielmann 《Journal of molecular medicine (Berlin, Germany)》1995,73(5):259-268
To investigate whether DNA replication in malignant cells deviates from that of normal cells we compared DNA polymerases , , and from normal rat liver to the enzymes from fast-growing (malignant) Novikoff hepatoma cells. DNA polymerases were purified 300-fold by three chromatographic steps. Characterization included measurement of physicochemical constants (including sedimentation coefficients, diffusion coefficients, calculation of relative molecular masses), quantitation of catalytic activities using specific DNA primer templates (K
m values) and inhibitors (K
i values), and identification of polypeptides which are strongly associated with DNA polymerases. Comparison of physicochemical and catalytic properties of DNA polymerases from both sources revealed similarities but also some important differences. DNA primase associated with DNA polymerase , and 3–5 exonuclease accompanying DNA polymerases and had similar activities. In contrast, the DNA-binding domain of DNA polymerases and from hepatoma cells was altered since K
m values, determined with the specific primer templates gapped calf thymus DNA and poly(dA·dT), were higher. Furthermore, sedimentation and diffusion coefficients, Stokes' radii, and frictional coefficient ratios of DNA polymerases and from malignant cells significantly deviated. In addition, when the dNTP-binding sites were probed with specific inhibitors (aphidicolin, butylphenyl-dGTP, carbonyldiphosphonate, and dideoxy-TTP), significantly lower K
i values were obtained for the polymerases from Novikoff cells indicating lower affinity of the dNTP binding site to deoxyribonucleoside 5-triphosphates. Altered catalytic and molecular properties are possibly a consequence of malignant transformation. It is to be expected that similar changes occur in DNA polymerases of other tumors. In particular, diminished affinity to primer templates and weakened nucleotide binding leads to lowered specificity of nucleotide selection in the base-pairing process and is therefore likely to cause an enhanced mutation rate during malignant progression.Abbreviations
PCNA 3
Proliferating-cell nuclear antigen
This paper is dedicated to Prof. Dr. R. Neidlein on the occasion of his 65th birthday. 相似文献
88.
本实验采用环磷酰胺(CY)制造免疫功能低下小鼠的动物模型,研究当归补血汤组成药物的不同比例配伍,对机体免疫功能调节作用的影响。实验过程中将当归、黄芪分别配制成1∶1(A方)、1∶5(B方)、5∶1(C方)的不同比例中药方剂,对小鼠施以灌胃,并设对照组,以WBC总数、T淋巴细胞转化率及胸腺细胞超微结构变化作为检测指标。结果表明:三组不同比例配伍的方剂,对小鼠机体免疫功能均有调节作用。三组之间比较,提高WBC总数以A方效果最明显;三个方剂均有促进淋巴细胞转化的作用,但转化率三者之间无明显差异;保护胸腺细胞作用以B方效果最好。应用:当归补血汤对机体免疫功能有明显调节作用,但不同比例配伍,对机体免疫功能调节作用各有所侧重 相似文献
89.
AIMS: The blastic variant of mantle cell lymphoma (MCL-BV) may develop through histological transformation of mantle cell lymphoma (MCL). However, the clonal link between the tumour cells of MCL and transformed MCL-BV has not been established at the genetic level. To investigate this link longitudinal molecular genetic studies have been performed in two cases of MCL that showed morphological transformation to MCL-BV. METHODS AND RESULTS: Polymerase chain reaction (PCR) and nucleotide sequence analyses of the complementary determining region 3 (CDR) of the immunoglobulin (Ig) heavy chain (H) gene were performed to identify clone-specific rearrangements. In both cases, nucleotide sequence analysis revealed common clone-specific IgH gene rearrangements in MCL and subsequent MCL-BV. CONCLUSIONS: These results provide genetic evidence for the common clonal origin of MCL and subsequently developed MCL-BV. 相似文献
90.
Hartmut F. Hildebrand Anne-Marie Decaestecker Fatima-Zohra Arrouijal Robert Martinez 《Archives of toxicology》1991,65(4):324-329
The uptake, the biological transformation and the interaction with cellular constituents of Ni3S2 and NiS have been studied in vitro and in vivo on rat lymphocytes. NiS crystals are phagocytized in vitro and no structural degradation is observed within the first 3 days of exposure. Energy dispersive spectrometry (EDS) reveals a slight dissolution characterized by the loss of sulfur. Ni3S2 is degraded in the extracellular space to minute particles (50–100 nm) covering the cell membrane. Smaller intracellular particles (10–30 nm) are found selectively bound to mitochondria, endoplasmic reticulum, Golgi vesicles, nuclear membranes, and the euchromatinic part of nuclei. EDS analyses reveal that the particles bound to cell membranes and euchromatin no longer contain sulfur but phosphorus and nickel as inorganic compounds. This observation suggests the formation of a Ni/P complex with the phosphate groups either of membranous phospholipids or of nuclear RNA or DNA. A similar uptake and transformation process of Ni3S2 is observed on lymphocytes after in vivo incubation. This leads us to consider lymphocytes as target cells, as compared with other cell types where the Ni3S2 uptake occurs only partially. The present findings show a difference of uptake and biological transformation between Ni3S2 and NiS. The identical results obtained after in vitro and in vivo bioassays enhance the in vitro experiments, at least for this cell type. 相似文献