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81.
Topical 5% alpha lipoic acid (ALA) has shown efficacy in treatment of photo-damaged skin. The aim of this work was to evaluate the potential of poloxamer (P407) gel as a vehicle for the novel lipid base particulate system (cubosome dispersions) of ALA. Cubosome dispersions were formulated by two different approaches, emulsification of glyceryl monoolein (GMO) and poloxamer (P407) in water followed by ultrasonication, and the dilution method using a hydrotrope. Three different concentrations of GMO were used to formulate the cubosome dispersions using the first method, 5% (D1), 10% (D2) and 15% w/w (D3). In the second technique an isotropic liquid was produced by combining GMO with ethanol, and this isotropic liquid was then diluted with a P407 solution (D4). The dispersions were characterized by zeta potential, light scattering techniques, optical and transmission electron microscopy, encapsulation efficiency and in vitro drug release. Results showed that D4 was not a uniform dispersion and that D1, D2 and D3 were uniform dispersions, in which by increasing the GMO content in the dispersion, the size of the cubosomes decreased, zeta potential became more negative, encapsulation efficiency increased up to 86.48% and the drug release rate was slower. P407 gels were prepared using the cold method. Two concentrations of P407 gel were fabricated, 20 and 30% w/w. P407 gels were loaded with either ALA or dispersions containing ALA cubosomes. P407 gels were characterized by critical gelation temperature, rheological measurements and in vitro drug release studies. Results suggested that by increasing P407 concentration, the gelation temperature decreases and viscosity increases. Drug release in both cases was found to follow the Higuchi square root model. Gel loaded with ALA cubosomes provided a significantly lower release rate than the gel loaded with the un-encapsulated ALA. A double blinded placebo controlled clinical study was conducted, aiming to evaluate the efficacy as an anti-wrinkle agent and volunteer’s satisfaction upon application of topical 30% P407 gel loaded with ALA cubosomes. Results indicated reduction in facial lines, almost complete resolution of fine lines in the periorbital region and upper lip area and overall improvement in skin color and texture in most volunteers. There were no instances of irritation, peeling or other apparent adverse side effects.  相似文献   
82.
目的 了解汕尾市育龄人群中α、β地中海贫血基因型的分布情况.方法 采用整群抽样方法选择2013年1月1日至2013年12月31日各地区部分住院分娩和引产的孕产妇、配偶共计1200例作为研究对象,分别进行α-地中海贫血和β-地中海贫血调查.结果 在1200份血液标本中共计检测出6种α-地中海贫血基因型,共计62例,63个等位基因,α-地中海贫血基因携带率为5.25%(63/1200).其基因型构成比:-a3.7/aa 31个,占总数的49.21%;-aSEA/aa 18个,占总数的28.57%;-a4.2/aa 7个,占总数的11.11%;-aTHAI/aa 2个,占总数的3.17%;--SEA/--SEA 3个,占总数的4.76%;--aCSa/aa2个,占总数的3.17%.有13例患者检测出携带β-地中海贫血基因,β-地中海贫血基因携带率为1.08%.基因类型共有5种,其构成比:IVS-2-654(C→T)和-28(A→G)各23.08%,CD41/42(-TCTT)30.77%,CD17(A→T)15.38%,βECD26(C→A)7.69%.结论 汕尾市区α-地中海贫血基因携带率和β-地中海贫血基因携带率从整个省份来讲相对较低,但分析自身数据来看携带率还是较高,主要发生在遗传背景较复杂的地区,并主要以本地人群为主.  相似文献   
83.
Introduction and objectivesOptimal treatment of hepatocellular carcinoma (HCC) involving portal vein tumor thrombus (PVTT) remains controversial.Materials and methodsA total of 627 HCC patients with PVTT after initial treatment with one of the following at Affiliated Tumor Hospital of Guangxi Medical University: liver resection (LR, n = 225), transarterial chemoembolization (TACE, n = 298) or sorafenib (n = 104) were recruited and randomly divided into the training cohort (n = 314) and internal validation cohort (n = 313). Survival analysis were repeated after stratifying patients by Cheng PVTT type.ResultsResection led to significantly higher OS than the other two treatments among patients with type I or II PVTT. TACE worked significantly better than the other two treatments for patients with type III. All three treatments were associated with similar OS among patients with type IV. These findings were supported by the internal validation cohort.ConclusionsOur results suggest that the optimal treatment for HCC involving PVTT depends on the type of PVTT. LR may be more appropriate for type I or II PVTT; TACE, for type III Sorafenib may be more appropriate than invasive treatments for patients with type IV PVTT.  相似文献   
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目的探讨足月新生儿肝母细胞瘤(HB)的CT特征。方法回顾性分析2015年1月至2019年1月在湖南省儿童医院经手术病理证实的7例新生儿肝母细胞瘤的临床资料及腹部CT表现特点,重点观察肿块的位置、大小、形态、密度及动态增强特征。结果7例HB患儿CT表现为肝内单发性肿块,其中累及肝Ⅵ段2例、肝Ⅶ段2例、肝Ⅴ+Ⅵ段1例、肝Ⅱ+Ⅲ段1例、肝Ⅳa+Ⅴ+Ⅷ段1例。肿瘤最大径为2.9~10.2 cm,中位数为4.7 cm;类球形4例,不规则分叶状且突向肝外生长3例;边界清晰6例,边界模糊1例;瘤内坏死囊变4例,钙化1例,小片状出血5例;7例肿瘤均呈不均匀强化,动脉期肿瘤中心及边缘出现多发结节状、条片状明显强化;门静脉期及延迟期强化呈进行性区域扩展、充填,呈多发条索状及"岛屿样"强化,且以边缘强化明显,坏死囊变区无强化;1例肿瘤侵犯门静脉及肝门区胆管,并肝内胆管扩张;3例腹腔干水平以下腹主动脉管径变细。病理诊断示肝母细胞瘤上皮胎儿型6例,混合型1例。结论新生儿HB的主要CT表现为可伴有不同程度坏死、出血及钙化的类球形或分叶状肿块,增强扫描呈进行性区域扩展的不均匀明显强化。  相似文献   
87.
BackgroundLow plasma level of alpha1-antitrypsin (AAT) is an established risk factor for early-onset chronic obstructive lung disease (COPD). However, less attention is given to the levels of AAT in the general population.MethodsThis is a part of a multicentre, population-based study conducted at 11 sites throughout Spain. Plasma levels of AAT were available for 837 persons with a mean (SD) age of 58.05 (11.3) years: 328-smokers, 272-ex-smokers and 237 non-smokers. Out of 837, 303 (36.2%) had a diagnosis of COPD, 222 (26.5%) had respiratory symptoms but no COPD, and 312 (37.3%) were healthy controls.ResultsIn the whole cohort, the mean level of plasma AAT was 1.51 (0.47) g/L. Levels were higher in COPD patients [1.55 (0.45) g/L] and individuals with respiratory symptoms [1.57 (0.47) g/L] than in controls [1.43 (0.47) g/L], p < 0.001, a finding which persisted after correction for age and CRP. Plasma AAT levels were negatively associated with FEV1/FVC ratio, after adjustment for age, sex, smoking status, CRP, TNFα, fibrinogen and albumin. The risk for COPD was significantly associated with higher AAT levels in univariate and multivariate models, with odds ratios of 1.8 and 1.5, respectively. In the univariate and multivariate models smoking status, gender, and CRP levels were also associated with COPD probability, demonstrating that they act independently.ConclusionIncreased circulating levels of AAT, similarly to CRP and other markers of systemic inflammation, is an important feature of COPD. Our results highlight a complex interrelationship between levels of AAT and health of respiratory system.  相似文献   
88.
This study investigated the stability and state-related characteristics of electroencephalographic (EEG) deviances in attention-deficit/hyperactivity disorder (ADHD). Three minutes resting EEG with eyes closed and eyes open were compared between 21 children with ADHD and 29 typically developing children. Across resting conditions, children with ADHD exhibited divergent topographic distribution for theta, alpha and beta power compared to typically developing children. In addition, less alpha and theta suppression to eye opening was found in children with ADHD, but only in those without comorbid ODD/CD. Findings of the present study refer to a consistent divergence in topographic distribution in ADHD across resting state conditions, yet demonstrate that state-related factors and comorbidity may also contribute to resting EEG deviances in ADHD. The state-related findings are in accord with several theoretical accounts emphasizing the role of contextual and state factors defining deficits in ADHD.  相似文献   
89.
Cap myopathy is a rare congenital myopathy characterized by the presence of caps within muscle fibres and caused by mutations in ACTA1, TPM2 or TPM3. Thus far, only three cases with TPM3-related cap myopathy have been described. Here, we report on the first autosomal dominant family with cap myopathy in three-generations, caused by a novel heterozygous mutation in the alpha-tropomyosin-slow-encoding gene (TPM3; exon 4; c.445C>A; p.Leu149Ile). The three patients experienced first symptoms of muscle weakness in childhood and followed a slowly progressive course. They presented generalized hypotrophy and mild muscle weakness, elongated face, high arched palate, micrognathia, scoliosis and respiratory involvement. Intrafamilial variability of skeletal deformities, respiratory involvement and mild cardiac abnormalities was noted. Muscle MRI revealed a recognizable pattern of fatty muscle infiltration and masseter muscle hypertrophy. Subsarcolemmal caps were present in 6–10% of the fibres and immunoreactive with anti-tropomyosin antibodies. We conclude that the MRI-pattern of muscle involvement and the presence of masseter muscle hypertrophy in cap myopathy may guide molecular genetic diagnosis towards a mutation in TPM3. Regular respiratory examinations are important, even if patients have no anamnestic clues. We compare our findings to all cases of cap myopathy with identified mutations (n = 11), thus far reported in the literature.  相似文献   
90.
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