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排序方式: 共有1453条查询结果,搜索用时 31 毫秒
1.
目的:建立侧向发育型肿瘤细胞(LST)株双向电泳技术.方法:提取LST细胞株总蛋白质,采用不同pH范围IPG胶条进行LST细胞株总蛋白质双向电泳,并对实验步骤进行一系列的调整优化.结果:获得了较为清晰的LST细胞株双向电泳图谱,采用pH 3~10线性IPG胶条分离出1356±43个蛋白质斑点;pH 4~7 IPG胶条两种上样量(250μg和150μg)分别分离出了1285±51和989个蛋白质斑点.结论:通过相关条件的调整优化,成功建立了双向电泳技术,为研究LST特殊性生物学行为相关蛋白质奠定了坚实的基础. 相似文献
2.
人大肠癌不同转移潜能细胞株SW620及SW480的差异蛋白质组分析 总被引:2,自引:0,他引:2
3.
Familial homozygous hypercholesterolemia: clinical and cardiovascular features in 18 patients 总被引:2,自引:0,他引:2
G J Brook S Keidar M Boulos E Grenadier A Wiener N Shehada W Markiewicz A Benderli M Aviram 《Clinical cardiology》1989,12(6):333-338
Homozygous familial hypercholesterolemia (HFH) is a very rare autosomal dominant disease characterized by accelerated severe atherosclerosis. We examined 18 patients from 9 families with HFH. The age range was 6-30 years (mean = 16 years). Male to female ratio was equal. All patients had huge, multiple tuberous xanthomas on the skin and tendons. Mean +/- standard deviation of plasma cholesterol, triglycerides, low-density lipoproteins (LDL), and high-density lipoproteins (HDL) cholesterol levels were 608 +/- 89, 122 +/- 39, 550 +/- 88, and 26 +/- 8 mg/dl, respectively. Five patients (28%) had angina pectoris, two sustained a myocardial infarction, and one died at the age of 15 years. Two-dimensional echocardiography demonstrated supravalvular aortic stenosis in 3 of the 13 patients (23%). Coronary arteriography performed in 11 patients demonstrated significant obstruction in 6 patients, 2 each with single-, double-, and triple-vessel disease. Left main stenosis was present in 3 patients (27%). Supravalvular aortic narrowing was demonstrated in 6 patients (54%) and was associated with a gradient in 2 (25 and 35 mmHg, respectively). Segmental contraction abnormalities were detected in 2 of the 11 patients (18%). It is concluded that coronary artery disease is prevalent in patients with HFH and, based on the data presented, we recommend the performance of noninvasive technique, coronary arteriography and supravalvular aortography at an early age to detect and to follow the progression of the disease. 相似文献
4.
Objective To explore the effect of L-canosine in preventing and treating rat cataract induced by sodium selenite. Methods This was an experimental study. Cataract was induced in the rats by sodium selenite. Rats were divided into 3 groups and each group has 3 ones. L-canosine eye drops (50 g/L or 20 g/L) and 0.9% normal saline were respectively instilled to the rat eye for 3 weeks and examined. L-canosine was added to the medium of cultured rat cataract lens at 1.00, 0.10 and 0.01 g/L for 1 week and then examined. Cataract lens were studied by using two-dimensional eletrophoresis. Results One week after instillation of L-canosine, the scores of rat cataract were 2.22±0.65, 2.39±0.98 and 2.83±0.38 in 50 g/L, 20 g/L L-canosine and control groups, respectively. The lesion in 50 g/l, L-canosine group was lighter than that of the control group. There was significant difference between these two groups (P=0.013). On the 2nd and 3rd weeks, there was no difference among these three groups. After 1 week for culturing cataract lens, there was no difference between these three groups. The results of two-dimensional eletrophoresis showed that the protein number was 182 and 161 in the L-carnosine and control groups, respectively. High molecular weight protein decreased and low molecular weight protein increased in L-carnosine group. Conclusions L-carnosine at 50 g/L could restrain the development of early stage rat cataract. L-camosine could modulate the rat lens protein in vitro, but could not affect lens cataract scores. 相似文献
5.
Terry M. Maloney Philip L. Paine Jose Russo 《Breast cancer research and treatment》1989,14(3):337-348
Summary The protein populations of epithelial cells cultured from two neoplastic and five non-neoplastic human breast tissues were resolved and displayed by two-dimensional polyacrylamide gel electrophoresis and silverstaining. With a computer-based image analysis system, we identified eight polypeptides which are present in both of the neoplastic cell lines, but absent from all five of the cultures of non-neoplastic breast cells. The eight polypeptides are not unique to cells cultured from neoplastic breast, because they are also found in cells cultured from non-breast tissues, both neoplastic and non-neoplastic. Two of the eight polypeptides ( Mr 25,000/pI 4.4 and Mr 31,000/pI 5.5) are present in the patterns of whole tissue samples from infiltrating ductal carcinomas and absent in most normal breast tissue. 相似文献
6.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure. 相似文献
7.
8.
目的 建立皮肤角朊细胞与表皮干细胞的双向电泳图谱,并分析二者表达蛋白质的差异,为进一步研究体外调控表皮十细胞的增殖、分化提供线索.方法酶消化法获取单个表皮细胞悬液.Ⅳ型胶原快速贴壁法分选表皮干细胞.利用舣向电泳技术(2-DE)建立两种细胞的蛋白质表达图谱,并用Imagemaster 2D elite 5.0软件分析两种细胞的差异表达蛋一点.结果两种细胞的2-DE蛋白表达谱具有良好的重复性和可比性.皮肤角朊细胞与表皮干细胞的电泳图谱平均蛋白质点数分别为(982 ±18)个和(930 ±15)个,匹配点数为(850±13)个和(798±11)个,匹配率是86.56%和85.81%;两种细胞蛋白质间匹配点数是(886 ±8)个,匹配率是76.98%.找到差异蛋白点11个,其中只在表皮下细胞中表达或高表达的有8个;只在皮肤角朊细胞中表达或高表达的有3个.结论利用双向电泳法得到了分辨率较高儿重复性好的皮肤角朊细胞与表皮干细胞蛋白质组图谱,且二者存在有一定的差异. 相似文献
9.
Mounir Fouad F Mamer O Khayyal M Sauriol F Lesimple A Ruhenstroth-Bauer G 《Medical hypotheses》2004,63(6):1024-1034
We are elaborating on the kinetics and mechanisms of septic rabbit liver to de novo biosynthesize acute-phase response (APR) proteins under in vitro conditions of deepening ischemia in reference to their in vivo prevalence in serum and cerebrospinal fluids (CSF) collected at predetermined times. The significance of the data is interpreted as relevant to grafting cadaveric liver into end-stage liver diseased patients and APR-induced ischemic heart diseases (IHD). Hepatic APR was induced by CCl(4)-intubation, and the administration of cholera toxin (CT) or scorpion venom (SV), or both, to rabbits. Hepatic functional efficiency, in terms of biosynthesis of APR proteins in closed circuit perfusion of the isolated intoxicated liver with oxygenated saline or L-15 media paralleled the two-dimensional immunoelectrophoresis (2D-IEP) spectrum of APR serum proteins at time of liver isolation. We are suggesting: (a) in vitro biosynthesis of plasma proteins by isolated perfused liver is the result of in vivo decoded and retained APR inflammatory signals; and (b) decoded inflammatory signals are expressed not withstanding the perfusate's organic composition. Furthermore, 90 min of ischemic perfusion in saline or L-15 medium precipitated mitochondrial aberrations which resulted in further deterioration of de novo biosynthesis of APR plasma proteins. Regardless of the nature of the inflammatory stimuli, mitochondrial aberrations rendered the perfused organ a biologically inert tissue mass that was incapable of resuming biological function upon perfusion with oxygenated L-15 medium. This is most likely due to ischemia-induced irreversible hepatic necrosis. Thus, in vitro aberrations of mitochondrial function(s) critically limit the capability of the isolated liver to resume its organic function to sustain biosynthesis of de novo plasma proteins. Extrapolation of these results to the surgical management of end-stage liver diseases points to the importance of the status and the handling protocol(s) of the cadaver donor liver prior to successful grafting. We conclude that although histology of a cadaver liver may reveal well-preserved hepatic cellular organelles with at least minimal intra- and intercellular communication required for viable hepatic function, we deem it essential to further define acceptable minimal capabilities to de novo biosynthesize plasma proteins by a cadaver liver as a measure of its functional viability and suitability for transplantation. Ultimately, this measure may improve the success of liver transplants with minimal surgical and drug interventions. 相似文献
10.
The crystal structure and nuclear magnetic resonance (NMR) spectra and assignments of celiprolol, N-[3-acetyl-4[3-[N-t-butylamino-2-hydroxypropoxy]phenyl]-N, N-diethylurea, are reported. Celiprolol crystallizes in the monoclinic space group, P2l/a, with a = 9.081(2), b = 13.800(4), and c = 17.471(5) Å and = 95.04(2)°. Structure was solved by direct methods; structure refinement to R of 0.058. Intermolecular hydrogen-bonding in the crystal is discussed. The 1H, 13C, and two-dimensional (2D) NMR spectra of the hydrochloride have been obtained and definitive signal assignments made. 相似文献