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951.
Eleven new indole alkaloids, in addition to the previously reported rhazinal (1), and 14 other known alkaloids, were obtained from the Malayan Kopsia singapurensis, viz., kopsiloscines A-F (2-7), 16-epikopsinine (8), kopsilongine- N-oxide (9), 16-epiakuammiline (10), aspidophylline A (11), and vincophylline (12). The structures of these alkaloids were determined using NMR and MS analyses. Rhazinal (1), rhazinilam (17), and rhazinicine (18) showed appreciable cytotoxicity toward drug-sensitive as well as vincristine-resistant KB cells, while kopsiloscines A (2), B (3), and D (5) and aspidophylline A (11) were found to reverse drug-resistance in drug-resistant KB cells.  相似文献   
952.
PurposeIn this study, we aimed to investigate the possible association between SLC2A1 26177A/G polymorphism and diabetic retinopathy (DR) in Malaysian patients with type 2 diabetes.MethodsGenomic DNA was extracted from 211 Malaysian type 2 diabetic patients (100 without retinopathy [DNR], 111 with retinopathy) and 165 healthy controls. A high resolution melting assay developed in this study was used to detect SLC2A1 26177A/G polymorphism followed by statistical analysis.ResultsA statistically significant difference in 26177 G minor allele frequency between healthy controls (19.7 %) and total patient group (26.1 %) (p < 0.05, Odd ratio = 1.437, 95% Confidence interval = 1.015–2.035) as well as between healthy controls (19.7 %) and DNR patients (27.5%) (p < 0.05, Odd ratio = 1.546, 95% Confidence interval = 1.024–2.336) was shown in this study. However, when compared between DR and DNR patients, there was no significant difference (p > 0.05).ConclusionsThis is the first study which shows that SLC2A1 26177G allele is associated with type 2 diabetes in Malaysian population but not with DR.  相似文献   
953.
Replication-competent, attenuated herpes simplex viruses (HSV) have been demonstrated to be effective oncolytic agents in a variety of malignant tumors. Cytokine gene transfer has also been used as immunomodulatory therapy for cancer. To test the utility of combining these two approaches, two oncolytic HSV vectors (NV1034 and NV1042) were designed to express the murine GM-CSF and murine IL-12 genes, respectively. These cytokine-carrying variants were compared with the analogous non-cytokine-carrying control virus (NV1023) in the treatment of murine SCC VII squamous cell carcinoma. All three viruses demonstrated similar infection efficiency, viral replication, and cytotoxicity in vitro. SCC VII cells infected by NV1034 and NV1042 effectively produced GM-CSF and IL-12, respectively. In an SCC VII subcutaneous flank tumor model in immunocompetent C3H/HeJ mice, intratumoral injection with each virus caused a significant reduction in tumor volume compared with saline injections. The NV1042-treated tumors showed a striking reduction in tumor volume compared with the NV1023- and NV1034-treated tumors. On subsequent rechallenge in the contralateral flank with SCC VII cells, 57% of animals treated with NV1042 failed to develop tumors, in comparison with 14% of animals treated with NV1023 or NV1034, and 0% of naive animals. The increased antitumor efficacy seen with NV1042 in comparison with NV1023 and NV1034 was abrogated by CD4(+) and CD8(+) lymphocyte depletion. NV1042 is a novel, attenuated, oncolytic herpesvirus that effectively expresses IL-12 and elicits a T lymphocyte-mediated antitumor immune response against murine squamous cell carcinoma. Such combined oncolytic and immunomodulatory strategies hold promise in the treatment of cancer.  相似文献   
954.
为提高对废用性骨质疏松与骨折的警惕性,探讨其防治措施,对13 例儿童因 髋关节疾病经手术、石膏固定术后1~9个月,发生废用性骨质疏松和骨折进行了回顾性分析 。结果:13例患儿15个部位发生了废用性骨折,经非手术疗法,配合药物治疗,获骨性愈合 。早期确定废用性骨质疏松的诊断,缩短不必要的肢体固定时间,尽早功能锻练,加强保护 ,避免外伤,配合内科药物疗法对防治本病有重要作用。  相似文献   
955.
In order to investigate the anti-tumor angiogenesis activity with a recombinant Ag43/FGFR1 chimeric protein(AF)vaccine in a mouse H22 hepatoma model,tumor volume and survival rate of the mice were studied at a 3-day interval.Microvessel density(MVD)was detected by immunohistochemistry.The endothelial deposition of autoantibodies within tumor tissues was examined by immunofluorescent staining,and anti-FGFR1 antibody-producing B cells(APBCs)were tested by enzyme-linked immunospot(ELISPOT)assay.Compared with t...  相似文献   
956.
Yim EK  Wan AC  Le Visage C  Liao IC  Leong KW 《Biomaterials》2006,27(36):6111-6122
A biofunctional scaffold was constructed with human mesenchymal stem cells (hMSCs) encapsulated in polyelectrolyte complexation (PEC) fibers. Human MSCs were either encapsulated in PEC fibers and constructed into a fibrous scaffold or seeded on PEC fibrous scaffolds. The proliferation, chondrogenic and osteogenic differentiation of the encapsulated and seeded hMSCs were compared for a culture period of 5.5 weeks. Gene expression and extracellular matrix production showed evidences of chondrogenesis and osteogenesis in the cell-encapsulated scaffolds and cell-seeded scaffolds when the samples were cultured in the chondrogenic and osteogenic differentiation media, respectively. However, better cell proliferation and differentiation were observed on the hMSC-encapsulated scaffolds compared to the hMSC-seeded scaffolds. The study demonstrated that the cell-encapsulated PEC fibers could support proliferation and chondrogenic and osteogenic differentiation of the encapsulated-hMSCs. Together with our previous works, which demonstrated the feasibility of PEC fiber in controlled release of drug, protein and gene delivery, the reported PEC fibrous scaffold system will have the potential in composing a multi-component system for various tissue-engineering applications.  相似文献   
957.
抗hER合成肽单克隆抗体的制备与鉴定   总被引:1,自引:0,他引:1  
王振明 Hong.  T 《免疫学杂志》1997,13(4):263-265
用合成的人雌激素受体(hER)抗原决定簇多肽(氨基酸序列从151~165)与KLH的偶联物为抗原,免疫BALB/C小鼠,经鼠-鼠杂交,ELISA和免疫细胞化学法筛选,有限稀释克隆化,得到一株分泌抗hER合成肽的杂交瘤细胞株(2B12)。用ELISA法测定。该纯化抗体10ng/ml仍与抗原反应,其免疫球蛋白为IgG2a.k。与MCF-7乳腺癌细胞溶解蛋白的Westernblot分析,在分子量67kD  相似文献   
958.
Antismoking mass media campaigns are known to be effective as part of comprehensive tobacco control programs in high-income countries, but such campaigns are relatively new in low- and middle-income countries and there is a need for strong evaluation studies from these regions. This study examines Malaysia's first national antismoking campaign, TAK NAK. The data are from the International Tobacco Control Malaysia Survey, which is an ongoing cohort survey of a nationally representative sample of adult smokers (18 years and older; N = 2,006). The outcome variable was quit intentions of adult smokers, and the authors assessed the extent to which quit intentions may have been strengthened by exposure to the antismoking campaign. The authors also tested whether the impact of the campaign on quit intentions was related to cognitive mechanisms (increasing thoughts about the harm of smoking), affective mechanisms (increasing fear from the campaign), and perceived social norms (increasing perceived social disapproval about smoking). Mediational regression analyses revealed that thoughts about the harm of smoking, fear arousal, and social norms against smoking mediated the relation between TAK NAK impact and quit intentions. Effective campaigns should prompt smokers to engage in both cognitive and affective processes and encourage consideration of social norms about smoking in their society.  相似文献   
959.
目的分析克罗恩病患者超声声像图特征,探讨超声检查评估克罗恩病活动性的价值。方法 2011年8月至2012年8月上海第十人民医院收治的克罗恩病患者25例。其中克罗恩病活动指数(CDAI)评分150分(缓解期)12例,150~450分(活动期)13例。每例患者均行内镜(结肠镜或小肠镜)检查、腹部超声检查。非炎性病变(缓解期)和炎症(活动期)肠段肠壁厚度比较采用两独立样本t检验。以内镜检查结果作为金标准,能量多普勒超声判断克罗恩病活动性与CDAI评分判断克罗恩病活动性的符合率比较采用χ2检验。结果 25例克罗恩病患者经内镜检查判断活动期20例,缓解期5例。所有患者均能获得满意的超声图像。本组超声诊断克罗恩病22例,诊断准确率为88%(22/25)。超声检测非炎性病变(缓解期)肠段肠壁厚度为(2.06±0.62)mm,低于炎症(活动期)肠段肠壁厚度(7.90±2.90)mm,且差异有统计学意义(t=2.53,P0.05)。本组25例克罗恩病患者能量多普勒超声判断缓解期7例,活动期18例。能量多普勒超声判断克罗恩病活动性的符合率为92%(23/25);而根据CDAI评分判断克罗恩病活动性的符合率仅为64%(16/25),低于能量多普勒超声判断克罗恩病活动性的符合率,且差异有统计学意义(χ2=9.39,P0.05)。超声检查发现腹腔脓肿1例,腹腔淋巴结肿大7例,腹腔积液2例。结论超声检查对肠壁厚度、结构层次、回声及肠外并发症的观察具有一定的优势,能准确评估克罗恩病活动性,对克罗恩病的诊治具有指导意义。  相似文献   
960.
目的 :比较非洛地平与依那普利对轻中度原发性高血压的降压疗效和安全性。方法 :72例轻中度原发性高血压患者随机接受非洛地平 (5 m g~ 2 0 mg)和依那普利 (5 mg~ 2 0 mg) (各 36例 )治疗 4周。结果 :非洛地平和依那普利的降压总有效率分别是 94.4%和91.3% (P>0 .0 5 )。结论 :非洛地平对轻中度原发性高血压疗效较好而且安全  相似文献   
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