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91.
以体外培养的猪主动脉内皮细胞(EC)为模型研究Ilopost对EC抗血栓功能的影响。用放免法、发色底物法测定培养液中6-酮-PGF1α(6-keto-PGF1α),血栓素B2(TXB2)含量,纤溶酶原激活物(PA),纤溶酶原激活物抑制物(PAI)活性及EC环磷酸腺苷(cAMP)含量。结果表明:Iloprost中以使EC生成6-keto-PGF1α,cAMP含量显著增多,TXB2含量显著减少,并使P 相似文献
92.
Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
Elevated blood pressure is an important risk factor for renal-, cerebro-
and cardiovascular diseases. We used an efficient discordant sib-pair
ascertainment scheme to investigate the impact of the distal end of the
long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing
genes for the alpha1B and beta2 adrenergic receptors and the dopamine
receptor type 1A on variation of systolic blood pressure in young
Caucasians. We measured eight highly polymorphic markers spanning this
positional candidate gene-rich region in 427 individuals from 55
three-generation pedigrees containing 69 discordant sibling pairs, and
calculated multipoint identity by descent (MIBD) probabilities. The results
of genetic linkage and association tests indicate that the region between
markers D5S2093 and D5S462 is significantly linked to one or more
polymorphic genes influencing interindividual variation in systolic blood
pressure levels. Since the alpha1B adrenergic receptor and dopamine
receptor type 1A genes are located close to these markers, these data
suggest that genetic variation in one or both of these G protein-coupled
receptors, which participate in the control of vascular tone, plays an
important role in influencing interindividual variation in systolic blood
pressure levels.
相似文献
93.
Yuning Xiong Kathleen A Donovan Michael P Kline Michael K Gornet Laurie L Moon-Tasson Martha Q Lacy Angela Dispenzieri Morie A Gertz Philip R Greipp John A Lust 《Journal of interferon & cytokine research》2006,26(2):83-95
Interleukin-1beta (IL-1beta) is abnormally expressed by the plasma cells obtained from myeloma patients, and it is a potent inducer of the important myeloma growth factor, IL-6. We investigated whether levels of IL-1beta biologic activity might distinguish different groups of patients with smoldering multiple myeloma (SMM). We measured the ability of IL-6 production by bone marrow stromal cells to serve as a surrogate marker for IL-1beta biologic activity. Using this IL-1beta bioassay, we found that it is sensitive at < 1 pg/ml of recombinant IL-1beta and that IL-1beta biologic activity is detectable with either mature or pro-IL-1beta-transduced myeloma cell lines. Patients with active myeloma induced quantitatively higher levels of stromal cell IL-6 production when compared with those with monoclonal gammopathy of undetermined significance (MGUS). The bioassay distinguished two groups of SMM patients, those who were high producers, similar to patients with active MM, and those who were low producers, comparable to MGUS patients. IL-1 antagonists inhibited the paracrine IL-6 production by > or = 90% in the majority of patients with an elevated IL-6 level. Based on such studies, it may be possible to predict patients that will progress to active MM and to delay or prevent this progression with IL-1 antagonists. 相似文献
94.
95.
氧离子注入增强人工关节软骨材料-UHMWPE的耐磨性 总被引:10,自引:0,他引:10
熊党生 《生物医学工程学杂志》2003,20(4):583-585,596
用高能离子注入机对超高分子量聚乙烯 (U HMWPE)进行了 O+注入改性 ,注入能量为 4 5 0 ke V和 10 0ke V,剂量分别为 1× 10 1 5/cm2 ,5× 10 1 5/cm2和 1× 10 1 6 /cm2。以 Si3N4 球为上销样 ,UHMWPE为下盘样组成摩擦副 ,在销盘摩擦试验机上评价它们在干摩擦和蒸馏水润滑条件下的磨损性能。结果表明 ,几种注入工艺均增强了UHMWPE的耐磨性 ,但提高了其摩擦系数 ,其中以能量为 4 5 0 Ke V,剂量为 5× 10 1 5/cm2的注入样品耐磨性最好。未注入 U HMWPE的磨损主要表现为黏着、塑性变形和犁沟 ,注入 U HMWPE的磨损主要为表面硬化层疲劳裂纹的萌生、扩展、剥落及磨粒磨损 相似文献
96.
In recent reports we described novel hybridization patterns (HP) corresponding to 22 potentially new HLA-B locus alleles in a panel of 547 subjects studied by PCR-SSOP. Three of them correspond to new subtypes of B35. To confirm the hybridization results we have isolated DNA from PBL and performed PCR, DNA cloning and nucleotide sequencing. One of the alleles, locally called B-3505v was found in three individuals: two Hispanic, one Caucasoid. It differs from B*3505 by 3 nucleotide substitutions that lead to changes in residues 94 (Ile > Thr), 95 (Ile > Leu) and 103 (Val > Leu). B-3505v differs from B*3501 in residues 97 and 103. Another allele called B-3508v, was found in 7 individuals, (6 of 122 Toba Indians, 1 of 18 Pilaga Indians). It differs from B*3509 in two silent nucleotide substitutions (codons 135 and 138) and in one substitution in residue 156 (Arg > Leu). The new allele has a hybrid sequence between B* 3508 and B*4801. A third subtype, locally called B-3504v, observed in two Hispanic individuals, is identical to B*3512. B*3512 differs from B*3504 by 3 nucleotides and one amino acid. Substitutions in residue 95 contribute to the structure of specificity pocket F, 97 to C and E, and 156 to pockets D and E. Therefore it is possible that some of the new alleles may have different peptide binding profiles. Since differences in residue 156 have been shown to affect allorecognition and mediate GvHD, identification of such variants may have important implications in transplantation and perhaps in studies of immune responses to peptides and pathogens. 相似文献
97.
本文研究绞股蓝总皂甙对血流动力学及缺氧性肺血管收缩反应的影响。14名男性志愿者口服20日后,基础血流动力学指标无显著变化,但HPV显著降低。服药后血小板活化程度,血浆血管紧张素Ⅰ、Ⅱ含量都明显降低。 相似文献
98.
用噬菌体表面展示技术筛选与肝癌细胞系结合的抗体模拟肽 总被引:1,自引:0,他引:1
目的:从噬菌体展示肽库中,筛选可与肝癌细胞特异性结合的抗体模拟肽。方法:通过生物淘选使噬菌体富集。利用ELISA法,鉴定噬菌体单克隆原种的亲和性,并进行统计学分析。通过竞争ELISA,分析筛选所得抗体模拟肽的结合位点,并进一步分析抗体模拟肽的序列组成。结果:随着淘选次数的增加,出现噬菌体的富集。ELISA的结果显示,相对于正常肝细胞,筛选所得环状7肽对肝癌细胞系SMMC7721和BEL7402均有良好的结合活性(P<0.05),且与SMMC7721细胞的结合活性明显优于与BEL7402细胞的亲和性(P<0.05)。在α=0.01的水平上,7肽单克隆噬菌体原种可明显与scFv竞争结合SMMC7721细胞(0.005
相似文献
99.
100.