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61.
Based on the DNA sequences of the junctions between recombinant and cotton genomic DNA of the two genetically modified (GM) cotton varieties, herbicide-tolerance Mon1445 and insect-resistant Mon531, event-specific primers and probes for qualitative and quantitative PCR detection for both GM cotton varieties were designed, and corresponding detection methods were developed. In qualitative PCR detection, the simplex and multiplex PCR detection systems were established and employed to identify Mon1445 and Mon531 from other GM cottons and crops. The limits of detection (LODs) of the simplex PCR were 0.05% for both Mon1445 and Mon531 using 100 ng DNA templates in one reaction, and the LOD of multiplex PCR analysis was 0.1%. For further quantitative detection using TaqMan real-time PCR systems for Mon1445 and Mon531, one plasmid pMD-ECS, used as reference molecule was constructed, which contained the quantitative amplified fragments of Mon1445, Mon531, and cotton endogenous reference gene. The limits of quantification (LOQs) of Mon1445 and Mon531 event-specific PCR systems using plasmid pMD-ECS as reference molecule were 10 copies, and the quantification range was from 0.03 to 100% in 100 ng of the DNA template for one reaction. Thereafter, five mixed cotton samples containing 0, 0.5, 0.9, 3 and 5% Mon1445 or Mon531 were quantified using established real-time PCR systems to evaluate the accuracy and precision of the developed real-time PCR detection systems. The accuracy expressed as bias varied from 1.33 to 8.89% for tested Mon1445 cotton samples, and from 2.67 to 6.80% for Mon531. The precision expressed as relative standard deviations (RSD) were different from 1.13 to 30.00% for Mon1445 cotton, and from 1.27 to 24.68% for Mon531. The range of RSD was similar to other laboratory results (25%). Concluded from above results, we believed that the established event-specific qualitative and quantitative PCR systems for Mon1445 and Mon531 in this study are acceptable and suitable for GM cotton identification and quantification.  相似文献   
62.
高必需氨基酸转基因马铃薯的研究   总被引:8,自引:0,他引:8  
80年代以来,马铃薯遗传转化系统日趋成熟,转基因工程植株已被广泛应用于基础科学研究[1]。作为食物蛋白和能量主要来源的马铃薯,提高其蛋白质含量及质量的遗传工程研究正受到人们的普遍关注[2]。Yang等[2]将旨在改善氨基酸平衡的CAT-HEAAE(氯酶素乙酰转移酶-高含量人体必需氨基酸)融合基因导入马铃薯,获得了Southernblot、Northernblot、Westernblot的证据,但尚缺少氨基酸分析的资料。玉米醇溶蛋白(zein)[3]是一个富含甲硫氨酸的贮存蛋白,它和人工合成的HE…  相似文献   
63.
Scaffold proteins play a crucial role in facilitating signal transduction in eukaryotes by bringing together multiple signaling components. In this study, we performed a systematic analysis of scaffold proteins in signal transduction by integrating protein-protein interaction and kinase-substrate relationship networks. We predicted 212 scaffold proteins that are involved in 605 distinct signaling pathways. The computational prediction was validated using a protein microarray-based approach. The predicted scaffold proteins showed several interesting characteristics, as we expected from the functionality of scaffold proteins. We found that the scaffold proteins are likely to interact with each other, which is consistent with previous finding that scaffold proteins tend to form homodimers and heterodimers. Interestingly, a single scaffold protein can be involved in multiple signaling pathways by interacting with other scaffold protein partners. Furthermore, we propose two possible regulatory mechanisms by which the activity of scaffold proteins is coordinated with their associated pathways through phosphorylation process.  相似文献   
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Objective

To explore the association between quality of life and social support in elderly osteoporosis patients in a Chinese population.

Methods

A total of 214 elderly patients who underwent bone mineral density screening were divided into two groups: elderly patients with primary osteoporosis (case group, n = 112) and normal elderly patients (control group, n = 102). Quality of life and social support were compared between the two groups.

Results

Quality of life and social support were significantly different between the case and control groups. The physical function, role-physical, bodily pain, general health, vitality, social-functioning, role-emotional and mental health scores in case group were significantly lower than those in the control group (P < 0.01). The objective support, subjective support, utilization of support, and total scores in case group were significantly lower than those in the control group (P < 0.01). Quality of life and social support were positively correlated in the case group (r = 0.672, P < 0.01).

Conclusion

Quality of life and social support in elderly patients with osteoporosis in China were poorer than in elderly patients without osteoporosis and were positively correlated. Our findings indicate that increased efforts to improve the social support and quality of life in elderly osteoporosis patients are urgently needed in China. Further longitudinal studies should be conducted to provide more clinical evidence to determine causative factors for the observed association between risk factors and outcomes.  相似文献   
66.
Human rights advocates play a critical role in promoting respect for human rights world-wide, and engage in a broad range of strategies, including documentation of rights violations, monitoring, press work and report-writing, advocacy, and litigation. However, little is known about the impact of human rights work on the mental health of human rights advocates. This study examined the mental health profile of human rights advocates and risk factors associated with their psychological functioning. 346 individuals currently or previously working in the field of human rights completed an internet-based survey regarding trauma exposure, depression, posttraumatic stress disorder (PTSD), resilience and occupational burnout. PTSD was measured with the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) and depression was measured with the Patient History Questionnaire-9 (PHQ-9). These findings revealed that among human rights advocates that completed the survey, 19.4% met criteria for PTSD, 18.8% met criteria for subthreshold PTSD, and 14.7% met criteria for depression. Multiple linear regressions revealed that after controlling for symptoms of depression, PTSD symptom severity was predicted by human rights-related trauma exposure, perfectionism and negative self-appraisals about human rights work. In addition, after controlling for symptoms of PTSD, depressive symptoms were predicted by perfectionism and lower levels of self-efficacy. Survey responses also suggested high levels of resilience: 43% of responders reported minimal symptoms of PTSD. Although survey responses suggest that many human rights workers are resilient, they also suggest that human rights work is associated with elevated rates of PTSD and depression. The field of human rights would benefit from further empirical research, as well as additional education and training programs in the workplace about enhancing resilience in the context of human rights work.  相似文献   
67.
A great deal of experimental evidence has accumulated in the past several decades, suggesting that polysaccharides have wide bioactivities. Cladonia furcata polysaccharide, CFP-2, a water-soluble lichenin with a mean Mr 7.6 x 10(4), was first obtained by 0.25 M NaOH solution extraction, ethanol precipitation, DEAE-cellulose, and Sephadex G-200 column chromatography. Gas chromatography of acid hydrolyzate of CFP-2 suggested that it was composed of D-glucose, D-galactose, and D-mannose in the molar ratios of 8:1:1. Periodate oxidation, Smith degradation, IR, and NMR spectroscopy analysis revealed that CFP-2 had a backbone consisting of alpha-(1-->3) and alpha-(1-->4)-linked D-glucopyranosyl residues substituted at O-6 with beta-(1-->6)-linked D-galactopyranosyl residue and alpha-(1-->6)-linked D-mannopyranosyl residue. CFP-2 was able to reduce viability of cultured HL-60 and K562 cells. The antiproliferative properties of CFP-2 appeared to be attributable to its induction of apoptotic cell death as determined by ultrastructural change, internucleosomal DNA fragmentation, and increased proportion of the subdiploid cell population. To elucidate molecular events in the apoptosis, protein expressions of Bcl-2, Bax, Fas, and FasL were measured by Western blotting using specific antibodies in HL-60 cells. The level of Bcl-2 remained largely unchanged, but the Bax, Fas, and FasL expression showed up-regulation. Moreover, the telomerase activity analyzed by TRAP-ELISA assay in HL-60 cells treated with CFP-2 decreased as compared with the untreated control cells. These results suggest that CFP-2 could have a possible cancer therapeutic potential.  相似文献   
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69.
目的 以hIL 1 β为炎症抗原诱导兔膝关节炎 ,观察评价其关节炎和滑膜炎的临床及病理特点。 方法 对通过逆转录病毒载体 (MFG)导入hIL 1 β基因的HIG 82细胞进行体外培养和筛选 ,之后注入 2 4只新西兰白兔的膝关节腔中 ,以注入异体兔滑膜细胞的 8只兔作对照。观察兔全身情况、膝关节局部及滑液的变化和滑膜炎的病理特点 ;并用RT PCR和ELISA法检测hIL 1 β的表达。 结果 转染的兔滑膜细胞系表达大量hIL 1 βmRNA ,分泌hIL 1 β浓度每毫升达 2~ 1 5ng 1 0 5细胞。关节炎滑膜组织有hIL 1 βmRNA的表达 ,关节腔灌洗液中hIL 1 β的浓度介于 2 0~ 6 0pg ml之间 ,血清中未检测到hIL 1 β。关节炎兔的血沉 (ESR)显著增快 ,是对照组的 1 0~ 1 5倍 ,并有发热、体重下降、厌食等全身表现 ;膝关节肿胀明显 ,直径较对照组增加 2 0 %~ 30 % ,滑液中白细胞数显著增加 ,达1 0 1 0 ~ 1 0 1 2 L ;关节炎的严重程度与注入关节腔的MFG hIL 1 β转染兔滑膜细胞数目成正相关。滑膜组织呈结节样增生 ,病理组织学分析显示 :滑膜细胞明显增生 ,可见栅栏样排列的滑膜细胞 ;滑膜基质增生显著 ,有大量中性粒细胞和淋巴细胞浸润 ,其间可观察到淋巴细胞聚集 ,并有纤维素样坏死和血管新生现象。滑膜炎在注入hIL 1 β 细胞后的  相似文献   
70.
The product of the retinoblastoma susceptibility gene (RB) was overproduced in cultured insect cells using the baculovirus expression system. Upon insertion of the cloned human RB complementary DNA sequence into the viral genome downstream of the promoter of the polyhedrin gene, full-length RB protein with an apparent molecular weight of 110,000 was expressed in the insect cells. This protein was found to be phosphorylated, located in the nuclei of the infected cells, and immunologically indistinguishable from pp110RB of human cells as assayed by several anti-RB antibodies. Following cell disruption and a one-step immunoaffinity chromatographic purification, 6-12 mg of soluble pp110RB with approximately 95% purity were obtained per liter of infected suspension culture. Characterization of the two known biochemical properties of RB protein showed that this purified protein from insect cells behaved similarly to the authentic human pp110RB. First, it bound to DNA, and second, it could form a specific complex with SV40 T antigen in vitro. Prompt translocation of the protein from cytoplasm to nucleus after microinjection further indicated that the purified RB protein may be active. The availability of soluble, intact, and presumably active pp110RB in large quantity represents a significant advance for studying the biochemical and biophysical properties of the RB gene product as well as its potential biological function in cancer suppression.  相似文献   
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