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271.
目的:探讨钒配合物LMc对拓扑异构酶Ⅰ、Ⅱ(Topo-Ⅰ、Topo-Ⅱ)的影响及其抗肿瘤活性。方法:采用DNA松弛实验观察LMC对Topo-Ⅰ、活性的影响并探讨其相关分子作用机制;采用MTT法、流式细胞术在细胞水平观察了IMC的抗肿瘤作用。结果:LMC可明显抑制Topo-Ⅰ活性,对Topo-Ⅱ无明显抑制作用,对多种肿瘤细胞株A549、Hela、BEL-7402具有明显抑制生长的作用,且可将细胞阻断在G2/M期,而对正常细胞株L-02生长无明显影响。结论:钒配合物LMC具有抑制Topo-Ⅰ活性而发挥抗肿瘤的作用。 相似文献
272.
云南大理人工松林中小兽群落与生态因子的关系 总被引:1,自引:0,他引:1
本文比较了云南大理不同年龄的人工松林(5-8年、10-15年、16-20年)中小兽群落的物种多度、多样性和主要小兽的丰富度,研究了小兽与森林栖境因子(乔木的密度、覆盖度和森林底层灌木和草本植物的覆盖度、密度、物种多度)的关系,探讨了小兽群落在中国西南人工森林的演替,以及地表植物和森林覆盖度对小兽群落的影响。研究结果显示,地表植物的物种多度和丰富度随着森林的年龄增长而增大,但是小兽群落的物种多度和多样性随着森林年龄的增长而变小。小兽与森林栖境因子的回归关系显示小兽群落的物种多度和多样性与地表植物(PC1)成负相关关系。小兽群落的优势物种随着森林的年龄有明显的演替。在年龄最小的森林(5-8年)中,大绒鼠(E.miletu)和齐氏姬鼠(A.chevrieri)是优势物种;在10-15年森林齐氏姬鼠(A.chevrieri)和锡金小鼠(M.pahari)是优势物种;在年龄最大的森林(16-20年)中,贝氏树(T.belangeri)和珀氏长吻松鼠(D.pernyi)成为优势物种 相似文献
273.
The method of affinity coelectrophoresis was used to study the binding of
nine representative glycosaminoglycan (GAG)-binding proteins, all thought
to play roles in nervous system development, to GAGs and proteoglycans
isolated from developing rat brain. Binding to heparin and non-neural
heparan and chondroitin sulfates was also measured. All nine
proteins-laminin-1, fibronectin, thrombospondin-1, NCAM, L1, protease
nexin-1, urokinase plasminogen activator, thrombin, and fibroblast growth
factor-2-bound brain heparan sulfate less strongly than heparin, but the
degree of difference in affinity varied considerably. Protease nexin-1
bound brain heparan sulfate only 1.8- fold less tightly than heparin
(Kdvalues of 35 vs. 20 nM, respectively), whereas NCAM and L1 bound heparin
well (Kd approximately 140 nM) but failed to bind detectably to brain
heparan sulfate (Kd>3 microM). Four proteins bound brain chondroitin
sulfate, with affinities equal to or a few fold stronger than the same
proteins displayed toward cartilage chondroitin sulfate. Overall, the
highest affinities were observed with intact heparan sulfate proteoglycans:
laminin-1's affinities for the proteoglycans cerebroglycan (glypican-2),
glypican-1 and syndecan-3 were 300- to 1800-fold stronger than its affinity
for brain heparan sulfate. In contrast, the affinities of fibroblast growth
factor-2 for cerebroglycan and for brain heparan sulfate were similar.
Interestingly, partial proteolysis of cerebroglycan resulted in a >400-
fold loss of laminin affinity. These data support the views that (1)
GAG-binding proteins can be differentially sensitive to variations in GAG
structure, and (2) core proteins can have dramatic, ligand-specific
influences on protein-proteoglycan interactions.
相似文献
274.
275.
Olga Nehir Oztel Seval Korkmaz Erdal Karaoz 《Preparative biochemistry & biotechnology》2020,50(2):156-163
AbstractBackrounds: According to the regulations of the health autorities, cell-based therapy products must be manufactured in good manufacturing production (GMP) facilities, fulfilling the required GMP standards. Products developed under the high quality control (QC) necessarity need to be approved for some QC tests. One of the main residual test is antibiotic test and this test should be validated. The aim of this study is to validate and determine the methods of detection of the antibiotic residue in the final product.Methods: Liquid Chromatography Tandem-Mass Spectrometry (LC-MS/MS) methods were used for the main steps of the production procedure, as well as the final products. Pharmaceutical Grade penicillin G and streptomycin sulfate were used as positive controls.Results: The results suggest that penicillin is broken down during cell culture and streptomycin is eliminated at the first washing step of the final product manufacture. It is shown in this study that LC-MS/MS method is one of the convenient method to test residual anibiotics and can be used to detect the antibiotic residues in cellular therapy products.Discussion: Since the antibiotic residues are eliminated in the final product and also it could be suggested that the methodology we followed is sufficiently safe and final product is pure. 相似文献
276.
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278.
Sukriye Ilkay Guner Savas Guner Erdal Peker Mehmet Fethi Ceylan Ayse Guler Ugur Turktas Barıs Kaki 《The Journal of membrane biology》2013,246(2):115-119
The purpose of this study was to investigate prospectively the effects of swaddling and consanguineous marriage on developmental dysplasia of the hip and associated risk factors. We screened by ultrasound 265 infants using the Graf method. The Pediatrics Department referred all newborn infants with suspected instability or a recognized risk factor to the orthopedic clinic. Risk factors of developmental dysplasia of the hip were searched and noted in these patients. Swaddling and consanguineous marriage were also determined and noted. We observed 164 of 265 infants (61.9 %) who had been swaddled and that 64 of 265 infants’ parents were in a consanguineous marriage (24.2 %). In the statistical analysis that was conducted for swaddling and consanguineous marriage, highly significant differences were found. Our study showed that the rate of developmental dysplasia of the hip is very high, 11.7 %, in our region, eastern Turkey. Also, we commonly see improper swaddling and consanguineous marriage in our region, which affects many infants. 相似文献
279.
Summary A Saudi Arabian family with 3 cases of Laurence-Moon-Biedl syndrome, 2 of whom are presumably identical twins, is presented. Although it is generally accepted that this condition is inherited as an autosomal recessive trait, no conclusive data exist in the literature to support this theory.
Zusammenfassung Wir präsentieren eine saudiarabische Familie, in der 2 Mitglieder vermutlich eineiige Zwillinge sind. In dieser Familie finden sich 3 Fälle von Laurence-Moon-Biedl-Syndrom. Wenngleich allgemein angenommen wird, daß dieser Zustand als autosomales recessives Merkmal vererbt wird, existieren hierfür keine überzeugenden Daten in der Literatur.相似文献
280.