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1.
DDPH[1-(2.6-二甲基苯乙氧基)-2-(3.4二甲氧基苯乙胺基)丙烷盐酸盐]是南京药科大学合成的降压新化合物,也具有降低肺动脉高压和抑制肺动脉平滑肌细胞增殖作用。本实验用细胞培养、免疫细胞化学、图像分析、3H-TdR、细胞周期测定等方法,进一步探讨DDPH对缺氧性肺动脉平滑肌细胞(PASMCS)增殖的抑制机制。结果:缺氧促进肺动脉内皮细胞(PAECs)的PDGF·BB和bFGF两种生长因子的表达(积分光密度OD值)增高。缺氧内皮细胞条件培养液(HECCM)能促进PASMCS的PDGF·BB的OD值增高,bFGF的OD值无明显改变。加药组(HEC-CM+DDPH)的PDGF·BB和bFGF的OD值均显著降低,尤以PDGF·BB的OD值减少最多.提示:DDPH能抑制HECCM引起PASMCS的PDGF·BB和bFGF表达增多和细胞增殖。结果与大鼠实验观察相符。  相似文献   

2.
为研究了我国不同地区不同人群中HDV毒株的感染分子特征,从我国河南,内蒙,北京,四川,广西西藏,新疆,辽宁,上海等地的HDV健康携带者,慢性丁肝病人与重症肝炎病人中筛选获得10余份HDV-RNA阳性血清,经逆转录-多聚酶链反应(RT-PCR)交叉扩增获得HDV抗原编码的cDNA片段并克隆到PGEM-3Zf(-)或PGEM-T载体上,经序列分析研究其基因结构特点,结果表明:中国的HDV毒株基因型元首  相似文献   

3.
中国不同丁型肝炎病毒株抗原编码区基因的cDNA特点分析   总被引:2,自引:0,他引:2  
谭文杰  詹美云 《病毒学报》1996,12(4):307-316
为研究我国不同地区不同人群中丁型肝炎(丁肝)病毒(HDV)毒株感染的分子特征,从我国河南,内蒙,北京,四川,广西,西藏,新疆,辽宁,上海等地的HDV健康携带者,慢性丁肝病人与重症肝病人中,筛选获得10余份HDV-RNA阳性血清,经逆转录-多聚酶链反应(RT-PCR)交叉扩增获得HDV抗原编码区的cDNA片段,并克隆到pGEM-3zf(-)或pGEM-T载体上,经序列分析研究其基因结构特点,结果表明  相似文献   

4.
1 书写方法 :①样本的算术平均数用英文小写 x表示 ,不用大写 X表示 ,也不同Mean或M (中位数仍用M) ;②标准差用英文小写s,不用SD ;③标准误用英文小写s x ,不用SE ,也不用SEM ;④t检验用英文小写t;⑤F检验用英文大写F ;⑥卡方检验用希文小写 χ2 ;⑦相关系数用英文小写r;⑧自由度用希文小写υ (钮 ) ;⑨样本数用英文小写n ;⑩概率用英文大写P ; 以上符号均用斜体。2 统计学处理必须标明检验方法 ,对结论性指标最好给出具体的检验值 ,如t值、χ2 值、Q值等 ,然后列出P值。3 关于“差异”的描述方法 :使用…  相似文献   

5.
基于小波变换的混合二维ECG数据压缩方法   总被引:5,自引:0,他引:5  
提出了一种新的基于小波变换的混合二维心电(electrocardiogram,ECG)数据压缩方法。基于ECG数据的两种相关性,该方法首先将一维ECG信号转化为二维信号序列。然后对二维序列进行了小波变换,并利用改进的编码方法对变换后的系数进行了压缩编码:即先根据不同系数子带的各自特点和系数子带之间的相似性,改进了等级树集合分裂(setpartitioninghierarchicaltrees,SPIHT)算法和矢量量化(vectorquantization,VQ)算法;再利用改进后的SPIHT与VQ相混合的算法对小波变换后的系数进行了编码。利用所提算法与已有具有代表性的基于小波变换的压缩算法和其他二维ECG信号的压缩算法,对MIT/BIH数据库中的心律不齐数据进行了对比压缩实验。结果表明:所提算法适用于各种波形特征的ECG信号,并且在保证压缩质量的前提下,可以获得较大的压缩比。  相似文献   

6.
应用蛋白dotblot技术检测了低氧内皮细胞条件培养液(HECCM)和常氧内皮细胞条件培养液(NECCM)内PDGF相对含量,并利用[3H]-TdR掺入法和流式细胞术观察了HECCM和NECCM及加入特异PDGF抗体对肺动脉平滑肌细胞(PASMC)生长的影响。结果表明,HECCM中的PDGF含量明显高于NECCM;HECCM能明显增强PASMC内DNA合成,促进PASMC从Go/G1期进入S期;当预先加入PDGF-B链抗体时,则会明显地抑制HECCM对PASMC的DNA合成,阻止PASMC从Go/G1期进入S期。结果提示,低氧时PASMC增殖与肺动脉内皮细胞分泌释放PDGF增加有关  相似文献   

7.
小波变换现已成为信号压缩的有力工具,小波压缩称法所基于的“嵌入零树小波”(EEW)编码已发展为心电信号进行综压缩。  相似文献   

8.
采用二维核磁共振技术,并借助一维技术DEPT对新倍半萜香豆素大果阿魏酮的全部^1H-NMR和^13C-NMR信号进行归属。应用X-衍射测定了其结构。  相似文献   

9.
表面电荷突变与胰蛋白酶底物专一性的改造   总被引:1,自引:0,他引:1  
分别利用酶切重组和“3+1”引物PCR定点突变的方法构建了三个胰蛋白酶表面电荷双突变体;R62D+K97E,R62D+K175E和K97E+K175E。对三在E.cloiX90菌中的表达产物进行了动力学测定,分别得到了三种双突变体在两种pH条件下,水解TAME,TLME两种底物的动力学数据。  相似文献   

10.
镉诱导蚯蚓金属硫蛋白的分离纯化及其溶液构象的研究   总被引:2,自引:0,他引:2  
镉诱导蚯蚓匀浆液经热沉淀,乙醇沉淀后,经凝胶过滤SephacryS-200柱层析,得三个镉结合蛋白峰,分子量依次为40,17及9kD。这三个组份再分别经DEAESepharose Fast Flow柱层析,分别得三、三、二个镉结合蛋白峰。根据光谱学特征、巯基含量及氨基酸组成等分析,认为凝胶过滤第二峰为金属硫蛋白(MT),其经DEAE柱层析所得三个峰为MT三个亚型。对蚯蚓MT三个亚型在不同PH条件下  相似文献   

11.
Two-dimensional gel electrophoresis was used to screen spring barley cultivars for differences in seed protein profiles. In parallel, 72 microsatellite (simple sequence repeat (SSR)) markers and 11 malting quality parameters were analysed for each cultivar. Over 60 protein spots displayed cultivar variation, including peroxidases, serpins and proteins with unknown functions. Cultivars were clustered based on the spot variation matrix. Cultivars with superior malting quality grouped together, indicating malting quality to be more closely correlated with seed proteomes than with SSR profiles. Mass spectrometry showed that some spot variations were caused by amino acid differences encoded by single nucleotide polymorphisms (SNPs). Coding SNPs were validated by mass spectrometry, expressed sequence tag and 2D gel data. Coding SNPs can alter function of affected proteins and may thus represent a link between cultivar traits, proteome and genome. Proteome analysis of doubled haploid lines derived from a cross between a malting (Scarlett) and a feed cultivar (Meltan) enabled genetic localisation of protein phenotypes represented by 48 spot variations, involving e.g. peroxidases, serpins, α-amylase/trypsin inhibitors, peroxiredoxin and a small heat shock protein, in relation to markers on the chromosome map. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

12.

Aims/Introduction

The incidence and prevalence of type 2 diabetes mellitus (T2DM) and related macrovascular complications in Korea were estimated using the Health Insurance Review and Assessment (HIRA) database from 2007–2011, which covers the claim data of 97.0% of the Korean population.

Materials and Methods

T2DM, coronary artery disease (CAD), cerebrovascular disease (CVD), and peripheral artery disease (PAD) were defined according to ICD-10 codes. We used the Healthcare Common Procedure Coding System codes provided by HIRA to identify associated procedures or surgeries. When calculating incidence, we excluded cases with preexisting T2DM within two years before the index year. A Poisson distribution was assumed when calculating 95% confidence intervals for prevalence and incidence rates.

Results

The prevalence of T2DM in Korean adults aged 20–89 years was 6.1–6.9% and the annual incidence rates of T2DM ranged from 9.5–9.8/1,000 person-year (PY) during the study period. The incidence rates of T2DM in men and women aged 20–49 years showed decreasing patterns from 2009 to 2011 (P<0.001); by contrast, the incidence in subjects aged 70–79 years showed increased patterns from 2009 to 2011 (P<0.001). The incidence rates of CAD and CVD in patients newly diagnosed with T2DM were 18.84/1,000 PY and 11.32/1,000 PY, respectively, in the year of diagnosis. Among newly diagnosed individuals with T2DM who were undergoing treatment for PAD, 14.6% underwent angioplasty for CAD during the same period.

Conclusions

Our study measured the national incidences of T2DM, CAD, CVD, and PAD, which are of great concern for public health. We also confirmed the relatively higher risk of CAD and CVD newly detected T2DM patients compared to the general population in Korea.  相似文献   

13.
Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, "DNABIT Compress" for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that "DNABIT Compress" algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases.  相似文献   

14.
2型糖尿病(type 2 diabetes mellitus,T2DM)是一种因胰岛素分泌不足或胰岛素抵抗而引起的慢性代谢疾病,T2DM患病人数的快速增长使治疗和预防T2DM成为世界上亟待解决的医学问题。随着微生物组学技术的进步,肠道菌群及其代谢产物与T2DM的研究亦逐渐深入,肠道菌群可能成为治疗和预防T2DM的靶点。肠道菌群及其代谢产物作用于T2DM的潜在机制,主要是参与体内炎症反应、增加肠道短链脂肪酸产量、调节肠道胆汁酸的代谢、调节支链氨基酸的代谢等。目前,治疗T2DM的药物可能会产生一些副作用,而基于肠道菌群干预T2DM的措施相对安全无害。例如,可通过严格控制的特定结构饮食长期摄入或增加益生菌的长期摄取控制血糖,或通过口服可影响肠道菌群生态结构的降糖药物(二甲双胍、阿卡波糖)有效地调控血糖水平。综述基于肠道菌群及其代谢产物诱发T2DM的潜在机制,研讨基于肠道菌群干预T2DM的措施,从肠道菌群的新视角探索治疗T2DM的新方法,为彻底治疗T2DM提供一种新可能。  相似文献   

15.
The aim of this study was to examine the antibacterial activity of raw donkey’s milk (DM) against Salmonella Enteritidis and Salmonella Typhimurium as well as to determine the dependence of this antibacterial activity on calcium, lysozyme and lactoferrin content. Antibacterial assays were conducted in DM artificially contaminated with these Salmonella serotypes and then incubated at 38 °C for 8 hours. Calcium concentration was found to have a strong influence on the antibacterial activity of the contaminated DM samples supplemented with CaCl2 and EDTA. The antibacterial activity of DM against the tested Salmonella strains was observed to be strongly calcium dependent, with the addition of CaCl2 to DM samples improving its antibacterial potential against both pathogens. Salmonella Enteritidis appeared to be less sensitive to the antimicrobial agents in DM than S. Typhimurium. One explanation is the calcium-dependant antibacterial activity of DM is attributable to the calcium-binding ability of its lysozyme. Lysozyme may be the main antibacterial agent, most probably via a nonenzymatic mode of action against tested Salmonella strains.  相似文献   

16.
One approach to correction of diabetes mellitus 2 type (DM2) and its complications is the use of bromocriptine mesylate (BCM), a selective agonist of the dopamine receptor type 2 (DA2R). However, the effectiveness and mechanisms of the action of BCM in the treatment of severe forms of DM2 forms currently not understood. The purpose of this study was to investigate the influence of 4-week treatment of male rats with neonatal DM2 model using BCM (300 mg/kg daily) on their metabolic parameters and on the activity of the adenylyl cyclase signaling system (ACSS) in the hypothalamus. Exposure to BCM restored glucose tolerance and glucose utilization by exogenous insulin, normalized lipid metabolism, and lowered triglycerides and atherogenic cholesterol levels, which are elevated in DM2. In the hypothalamus of diabetic rats treated with BCM, the regulation of ACSS by agonists of melanocortin receptors type 4 (MC4R), DA2R, and serotonin 1B-subtype receptors and expression of the Mc4r gene encoding MC4R were restored. Furthermore, BCM treatment did not influence the insulin levels in the blood and its production by pancreatic β-cells. The data indicate that the use of BCM to correct severe forms of experimental DM2 holds promise and show that the therapeutic potential of this drug is based on its ability to restore signaling systems of the hypothalamus that are sensitive to monoamines and peptides of the melanocortin family, which are responsible for the control of energy metabolism and insulin sensitivity.  相似文献   

17.

Objective

Paraoxonase-1 (PON1), an HDL-C associated enzyme, protects lipoproteins from oxidation. There is evidence that PON1 enzyme activity is reduced in the patients with type 2 diabetes mellitus (T2DM). North-West Indian Punjabis, a distinct ethnic group has high incidence of T2DM. However till date there is no information regarding PON1 enzyme activities and PON1 polymorphisms in T2DM patients of this ethnic group.

Methods

We identified polymorphisms in the coding Q192R, L55M and promoter − 909G/C, − 162A/G, − 108C/T of the PON1 gene by using PCR-RFLP, multiplex PCR and allele specific oligonucleotide PCR assays in 250 T2DM patients and 300 healthy controls. We also assessed paraoxonase (PONase) and arylesterase (AREase) activities of PON1 enzyme.

Results

The serum PONase (114.2 vs. 178.0 nmol/min/ml) and AREase (62.7 vs. 82.5 μmol/min/ml) activities were significantly lower (p < 0.0001) in patients as compared to controls. PONase activity was affected by all the studied PON1 polymorphisms. However, AREase activity was not affected by any of these polymorphisms. Coding Q192R and promoter − 909G/C polymorphisms showed significant differences in genotypic distribution. QR, RR (Q192R) and GC, CC (− 909G/C) genotypes and L-C-A-R-G, L-T-A-R-G, L-T-G-Q-C haplotypes showed significant association with type 2 diabetes. No significant linkage disequilibrium was observed among the five polymorphisms.

Conclusion

Both PONase and AREase activities are lower in patients and this could lead to increased lipid peroxidation and accelerated atherosclerosis in them. PONase activity, but not AREase activity is influenced by PON1 polymorphisms. QR, RR, GC, CC genotypes and L-C-A-R-G, L-T-A-R-G, L-T-G-Q-C haplotypes are commoner in diabetics as compared to controls and may be related to genetic susceptibility to type 2 diabetes.  相似文献   

18.

Introduction

Diabetes mellitus (DM) has the potential to impact the pathogenesis, treatment, and outcome of pancreatic cancer. This study evaluates the impact of DM on pancreatic cancer survival.

Methods

We conducted a retrospective cohort study from the Veterans Affairs (VA) Central Cancer Registry (VACCR) for pancreatic cancer cases between 1995 and 2008. DM and no-DM cases were identified from comorbidity data. Univariate and multivariable analysis was performed. Multiple imputation method was employed to account for missing variables.

Results

Of 8,466 cases of pancreatic cancer DM status was known in 4728 cases that comprised this analysis. Males accounted for 97.7% cases, and 78% were white. Overall survival was 4.2 months in DM group and 3.6 months in the no-DM group. In multivariable analysis, DM had a HR = 0.91 (0.849–0.974). This finding persisted after accounting for missing variables using multiple imputations method with the HR in DM group of 0.93 (0.867–0.997).

Conclusions

Our data suggest DM is associated with a reduction in risk of death in pancreatic cancer. Future studies should be directed towards examining this association, specifically impact of DM medications on cancer outcome.  相似文献   

19.
Copper (Cu) is an important trace element involved in oxidative stress, which is associated with the onset and progression of diabetes mellitus (DM). However, clinical studies comparing plasma or serum Cu levels in patients with DM and in healthy individuals report conflicting findings. Therefore, in this meta-analysis, we analyzed the circulating levels of Cu associated with DM (including type 1 diabetes mellitus [T1DM] and type 2 diabetes mellitus [T2DM]). We searched the articles indexed in PubMed, OVID, and Cochrane databases, published through January 2016 and meeting our predefined criteria. Requisite data were extracted, and a random-effect model or a fixed-effect model was used to conduct the meta-analysis. Fifteen eligible studies involving a total of 1079 DM patients and 561 healthy controls were identified. Overall, the DM patients showed higher Cu levels than the healthy controls (plasma Cu mean difference [MD] = 1.69 μmol/L, p < 0.0001; serum Cu MD = 4.06 μmol/L, p = 0.005; plasma and serum Cu MD = 2.67 μmol/L, p = 0.006). Stratification based on the type of diabetes also indicated higher levels of Cu in the plasma and serum of DM patients than in healthy controls, respectively. Stratification of DM patients associated with and without complications also revealed similar results. This meta-analysis suggests that DM patients carried higher levels of Cu than healthy individuals. However, international cohort studies are needed to corroborate our findings.  相似文献   

20.
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