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11.
Pyrrole polyamide-2′-deoxyguanosine 5′-phosphate hybrid (Hybrid 4) was synthesized and evaluated in terms of the inhibition of mouse mammary carcinoma FM3A cell growth. Hybrid 4 was found to exhibit dose-dependent inhibition of cell growth.  相似文献   
12.
目的:分析经额底纵裂入路治疗鞍上第三脑室底垂体瘤的疗效,探讨其临床适用性。方法:选择从2011年1月~2013年1月与我院行额底纵裂入路手术治疗的30例鞍上第三脑室底垂体瘤的患者,术中行单侧额或双侧额弧形切口,根据术中所见肿瘤位置,由终板、视神经一颈内动脉等存在的生理间隙处切除肿瘤,观察所有患者的手术疗效。结果:所有患者术中可见肿瘤位于鞍内鞍上,部分或全部突入第三脑室底,其中有6例患者伴有脑积水。术中肿瘤全切23例,次全切5例,大部切除2例,无手术死亡病例。术前25例患者视力减退,术后23例患者视力均获得不同程度改善,仅1例暂无明显变化。术后19例出现电解质紊乱,患者经治疗后均已纠正;12例出现不同程度的尿崩症,给予患者药物治疗后,病情得到缓解。术后随访6个月,23例肿瘤全切患者病灶无复发,另外4例次全切者病灶也无明显变化,仅1例次全切和2例大部切除患者于术后行伽马刀再次治疗。结论:经额底纵裂入路治疗鞍上第三脑室底垂体瘤可以达到视野清晰,直观下进行肿瘤切除,手术效果好,并发症较少,适合临床长期推广应用。  相似文献   
13.
Vitamin B12 is an essential micronutrient synthesized by microorganisms. Mammals including humans have evolved ways for transport and absorption of this vitamin. Deficiency of vitamin B12 (either due to low intake or polymorphism in genes involved in absorption and intracellular transport of this vitamin) has been associated with various complex diseases. Genome-wide association studies have recently identified several common single nucleotide polymorphisms (SNPs) in fucosyl transferase 2 gene (FUT2) to be associated with levels of vitamin B12—the strongest association was with a non-synonymous SNP rs602662 in this gene. In the present study, we attempted to replicate the association of this SNP (rs602662) in an Indian population since a significant proportion has been reported to have low levels of vitamin B12 in this population. A total of 1146 individuals were genotyped for this SNP using a single base extension method and association with levels of vitamin B12 was assessed in these individuals. Regression analysis was performed to analyze the association considering various confounding factors like for age, sex, diet, hypertension, diabetes mellitus and coronary artery disease status. We found that the SNP rs602662 was significantly associated with the levels of vitamin B12 (p value < 0.0001). We also found that individuals adhering to a vegetarian diet with GG (homozygous major genotype) have significantly lower levels of vitamin B12 in these individuals. Thus, our study reveals that vegetarian diet along with polymorphism in the FUT2 gene may contribute significantly to the high prevalence of vitamin B12 deficiency in India.  相似文献   
14.
ERCC4 plays an essential role in the nucleotide excision repair (NER) pathway, which is involved in the removal of a wide variety of DNA lesions. To determine whether the ERCC4 tagging SNPs (tSNPs) are associated with risk of gastric cancer, we conducted a hospital-based case-control study of 350 cases and 468 cancer-free controls. In the logistic regression (LR) analysis, we found a significantly decreased risk of gastric cancer associated with the rs744154 GC/CC genotypes [adjusted odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.42–0.75, false discovery rate (FDR) P = 0.003] compared with the wild-type GG genotype. Haplotype-based association study revealed that the CGC haplotype that containing the rs744154 C allele can decrease the risk of gastric cancer compared with the most common haplotype GGT (adjusted OR = 0.61, 95% CI = 0.46–0.81). Using the multifactor dimensionality reduction (MDR) analysis, we identified that the SNP rs744154 and smoking status were the best two predictive factors for gastric cancer with a testing accuracy of 55.76% and a perfect cross-validation consistency (CVC) of 10 (P = 0.001). Furthermore, the smokers with the rs744154 GC/CC genotypes showed a decreased risk of gastric cancer (adjusted OR = 0.55, 95% CI = 0.35–0.85) compared with the smokers with the GG genotype using multivariate LR analysis. The above findings consistently suggested that genetic variants in the ERCC4 gene may play a protective role in the etiology of gastric cancer, even in the smokers.  相似文献   
15.
Studies focusing on the association of gene methylthioadenosine phosphorylase (MTAP) with the risk of coronary artery disease (CAD) and myocardial infarction (MI) are limited.  相似文献   
16.
Vascular malformations (VMs) are common congenital and neonatal dysmorphogenesis. VMs mostly occur sporadically with a few exceptions of inheritability. Tie2/angiopoietins-2 (Ang-2) and VEGF/KDR pathways are known to be involved in normal and pathogenic angiogenesis. Our study was aimed to test the contribution of these pathway gene variants to VMs. A total of 8 variants were found among 103 VM patients and 142 healthy controls. These variants comprised rs638203, rs639225, rs80338908 and rs80338909 in Tie2 gene, rs1870377 and rs2305949 in KDR gene, rs79337921 and rs34590960 in ANTXR1 gene. Our results indicated that rs638203 (p = 0.029) and rs639225 (p = 0.018) in Tie2 gene were associated with VM. A further bioinformatics analysis suggested the rs638203-G and rs639225-G might cause an abnormal splicing of Tie2 gene into to a defective protein. Our results identified two novel Tie2 gene polymorphisms with genetic susceptibility to VMs, although future functional validation of the two polymorphisms is warranted in the future.  相似文献   
17.
In situ ellipsometry was employed to study adsorption from human palatal saliva (HPalS) in terms of dependence on surface wettability and saliva concentration ( ? 1%). Adsorbed amounts, kinetics, and elutability with buffer and sodium dodecyl sulphate (SDS) were determined. The low-molecular weight protein content of bulk HPalS was also investigated using two-dimensional gel electrophoresis, and this revealed the presence of a large group of proteins < 100 kDa in size. Adsorption to pure (hydrophilic) and methylated (hydrophobized) silica surfaces revealed that the total adsorbed amounts were greater on hydrophobized silica. Below concentrations of 0.5 and 0.25% saliva, adsorption was concentration dependent on hydrophobized and hydrophilic surfaces, respectively. The initial adsorption ( ? 30 min) was faster on hydrophobized surfaces. Addition of SDS removed more material than buffer rinsing on both surfaces. Analysis of the adsorption kinetics indicated that the presence of low-molecular weight proteins plays a role in adsorption from HPalS.  相似文献   
18.
Patterns of reproduction were investigated in some microalgal species of Chlorophyceae (Botryosphaerella sudetica, Neochloris aquatica, Neochloris vigensis, Bracteacoccus minor). Under continuous light, the microalgae reproduced asexually producing autospores. However, appropriate manipulation of external conditions led to a change in the reproduction pattern towards production of zoospores or gametes. Production of zoospores and gametes was inhibited by light; motile cells emerged when microalgae were cultivated in darkness. The period of dark treatment necessary for zoosporogenesis or gametogenesis differed substantially among species that were tested. Sexual reproduction was observed in Neochloris vigensis and Bracteacoccus minor, whose generative life cycle had not been previously reported. The morphology of motile cells, the mode of sexual reproduction, and the efficiency of both the production of motile stages and mating events, were investigated. In order to gain detailed insights into patterns of reproduction, Botryosphaerella sudetica was selected for investigation under different light treatments. Non-actinic red light applied in the early phase of dark cultivation (up to 2 h) suppressed both zoosporogenesis and gametogenesis. However, after a 3-h dark pre-treatment, red light treatment had no effect on zoosporogenesis or gametogenesis. In contrast, non-actinic blue light did not block zoosporogenesis or gametogenesis, regardless of the time of treatment. The possible role of a red-light photoreceptor in zoosporogenesis and gametogenesis is discussed.  相似文献   
19.
小朱兰在广东的首次记录及其意义   总被引:1,自引:0,他引:1  
曾宪锋 《广西植物》2013,(6):798-800
报道了广东省朱兰属1新记录——小朱兰,并论述了它的分类学、区系学意义。  相似文献   
20.
An extract of Ulmus macrocarpa Hance, commonly known as the large-fruited elm, has been prescribed as a traditional medicine. In this study, we aimed to investigate the cellular immune effects of U. macrocarpa stem cortex extracts on cyclophosphamide (CY)-treated splenocytes and mice. A methanol extract showed an improved survival rate of splenocytes after 72?h. The extract was successively partitioned with dichloromethane, ethyl acetate, n-butanol, and water; and the fractions so obtained were also examined for their proliferative activity. Among them, the water fraction of U. macrocarpa showed the highest proliferation of splenocytes and was used throughout the present study. We tested the survival rate of splenocytes through dose-dependent treatment of CY and the suppression of the survival effect by CY was recovered by treatment with the water extract of U. macrocarpa. To determine the mechanism involved, we examined the expression of B-cell lymphoma-extra large (Bcl-xL) anti-apoptotic protein. CY decreased Bcl-xL protein levels in resting splenocyte cultures, whereas splenocytes were exposed to water extracts of U. macrocarpa in the presence of CY; however, elevations in Bcl-xL were observed at 96?h. Mice splenocytes treated with water extract of U. macrocarpa for cellular immunity showed an increase in the activity of the mixed lymphocyte reaction (MLR), cytotoxic T lymphocytes (CTLs), and natural killer (NK) cells. In addition, mice receiving a water extract of U. macrocarpa recovered the CTL, NK, and MLR activities suppressed by CY administration. Consequently, U. macrocarpa improves the cell-mediated immune response and provides an insight on cell-based tonic materials.  相似文献   
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