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1.
鲨鱼软骨血管生成抑制因子的纯化和功能 总被引:25,自引:0,他引:25
以中国东海鲸鲨软骨为原料,通过盐抽提、丙酮分级沉淀、离子交换层折、分子筛层析、高效液相色谱等步骤,获得鲨鱼软骨血管生成抑制因子-I(shark cartilgae angiogenesis inhibitory factor-I,SCAIF-I),对其分子量、抑制血管生成及抑制肿瘤生长活性进行了研究。结果显示SCAIF-I分子量18kD,在细胞和整体水平上显著抑制新血管生成,显著抑制小鼠肿瘤的生长 相似文献
2.
色素上皮衍生因子(pigment epithelium—defived factor,PEDF)是一种具有神经营养保护、抑制新生血管增生和抑制肿瘤生长等作用的多功能蛋白质。体内外试验证明,PEDF通过抑制新生血管生成、诱导肿瘤细胞分化和抑制肿瘤细胞增殖及迁移等多个环节抑制肿瘤的生长,成为治疗肿瘤的候选药物。 相似文献
3.
鲨鱼软骨制剂抑制血管生成的研究 总被引:23,自引:0,他引:23
以鲨鱼软骨为原料,经盐酸胍抽提,丙酮分级沉淀, 超滤等步骤得到鲨鱼软骨制剂(shark cartilage preparation,SCP). 利用整装细胞扫描电镜方法测定SCP对血管内皮细胞骨架系统的影响,体外细胞迁移实验测定它对内皮细胞迁移的抑制效应,及鸡胚绒毛尿囊膜实验测定对血管生成的抑制效应. 结果表明SCP能显著抑制内皮细胞的骨架形成;显著抑制内皮细胞的迁移,并有明显的浓度依赖关系;显著抑制鸡胚绒毛尿囊膜的血管生成. 细胞骨架是细胞分裂增殖及运动迁移的基础,血管内皮细胞的运动迁移又是血管生成的基础,因此SCP的作用机理可能是通过抑制细胞骨架的形成,抑制内皮细胞的运动迁移,从而抑制血管生成. 相似文献
4.
血管抑素是第一个被发现的肿瘤源性血管生成抑制因子,能抑制血管内细胞的增殖和迁移,从而抑制肿瘤的生长。通过一些实验方法能够检测肿瘤患者体内的血管抑素水平。血管抑素在未来的肿瘤治疗、诊断、预后判断和新生血管疾病的治疗中有着广阔的应用前景。 相似文献
5.
血管抑素是第一个被发现的肿瘤源性血管生成抑制因子,能抑制血管内细胞的增殖和迁移,从而抑制肿瘤的生长。通过一些实验方法能够检测肿瘤患者体内的血管抑素水平。血管抑素在未来的肿瘤治疗、诊断、预后判断和新生血管疾病的治疗中有着广阔的应用前景。 相似文献
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刘锦孙立袁胜涛 《现代生物医学进展》2011,11(5):978-981
血管的生成与肿瘤密切相关,抑制肿瘤血管生成可以调节肿瘤的生长。体内存在着内源性的促血管生成因子和抑制因子的平衡,当促血管形成因子增强就会产生新生血管供肿瘤生长,而当抑制因子增强则会抑制肿瘤的生长。本文即对细胞外基质衍生的内源性血管生成抑制因子TSP、内皮他丁、Arresten;Canstatin、Endorepellin、Fibulin、Tumstatin等的特性、应用和作用机制等作一总结。 相似文献
10.
肿瘤生长抑制因子—血管抑素和内皮抑素 总被引:1,自引:0,他引:1
血管生成是肿瘤生长转移过程中的一个关键环节,因此控制血管生成成为抑制肿瘤生长的重要途径之一。目前已发现了许多血管生成抑制因子,尤以血管抑素和内皮抑素最为引人瞩目。综述了两种肿瘤生长抑制因子的发现、分子结构、生物学活性等,尤其侧重于它们抗肿瘤作用的实验研究。血管抑素与内皮抑素的发现与研究为恶性肿瘤的治疗开辟了新的道路。 相似文献
11.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare
these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow
the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human
serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three
reconstituted reference serum samples by comparison with other methods and by the standard addition procedure.
The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision,
and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest
in the environment, the relatively delicate sample handling, and the high cost of the equipment. 相似文献
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Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons. 相似文献
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A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability. 相似文献
14.
G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
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The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid. 相似文献
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Vladimir Zaichick Sofia Zaichick Vasilii Karandashev Sergey Nosenko 《Biological trace element research》2009,129(1-3):107-115
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs. 相似文献
18.
Monovalent Cation Permeation through the Connexin40 Gap Junction Channel : Cs,Rb, K,Na, Li,TEA, TMA,TBA, and Effects of Anions Br,Cl, F,Acetate, Aspartate,Glutamate, and NO3 下载免费PDF全文
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl− (0.19), glutamate− (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius. 相似文献
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Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera.
The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents
and shown to be controlled by three alleles,C
12,C
25, andC
−. A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled
by six codominant alleles (G
10.19.20,G
10.19,G
10.20,G
10,G
19,G
20) and a recessive allele (G
−). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion
probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively.
This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia. 相似文献
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