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91.
《Vaccine》2019,37(36):5390-5396
ObjectiveThe purpose of this study was to track and describe the absolute number of vaccine administration errors and corresponding error rates over time and by patient age and vaccine type.MethodsTotal vaccines administered to patients aged 0 through 19 years 364 days from 1/1/2006 through 12/31/2017 at a large academic health system in the Midwest United States with primary, specialty and school-based clinics, and a pediatric hospital were obtained from an electronic medical record. Vaccine administration errors over the same time period for the same patient criteria were analyzed from the health system’s incident reporting system and further compared to the frequency of all incidents reported. Vaccine administration error rates were calculated. Data were analyzed by patient age, vaccine type and year administered.ResultsOf the 1,431,206 vaccine doses given, 552 vaccine administration errors were identified (0.04%). The highest error rates occurred in children aged 2, 3, and 19 years. Vaccine types with the highest error rate were Td, rabies and pneumococcal polysaccharide vaccines. Overall vaccine doses given and errors reported increased over the study period. However, the increase was disproportionate, resulting in an increase in the error rate initially followed by a stabilization at the end of the study period.ConclusionsVaccine administration errors are uncommon. The error rate appears to be stabilizing. Errors are more likely at ages when vaccines are not commonly given, with vaccines that have age-specific dosing and with vaccines that are given less often. This suggests more safety checks are needed for vaccines that are rarely used or given off-schedule, and manufacturers should avoid vaccines with age-specific dosing.  相似文献   
92.
The porcine circovirus type 2 (PCV2) is a swine infectious viral pathogen of great significance in global swine herds. It was recently detected at another Province of South Africa sequel to the first detection of North American‐like strain (PCV2a) at Gauteng about two decades ago, but there is a dearth of information about the genomic features and diversity of the viral strains in circulation within the country and the entire sub‐Saharan Africa region. To date, only one complete genome of the virus from South Africa is available on global data base. This current effort is therefore geared towards the full‐genome characterization of the circulating PCV2 strains in the pigs of Eastern Cape Province. With the use of conventional polymerase chain reaction method, fifteen complete PCV2 genomes were successfully amplified, sequenced and assembled from field samples obtained from non‐vaccinated pigs in the region. Neighbor Joining and Maximum Likelihood phylogenetic analyses of the ORF2 gene and full genomes unanimously showed that most of the assembled genomes (11) belong to genotype PCV2b. Furthermore, three of the characterized sequences formed clade with other reference mutant PCV2b and PCV2b subtype 1C (i.e. PCV2d) strains from the USA, China and South Korea. The last sequence, however, clustered with other reference strains belonging to PCV2 intermediate clade 2 (PCV2‐IM2), recently identified in a global PCV2 strains phylogenetic analysis. This study reports the first complete genome sequences of PCV2b, PCV2d and PCV2‐IM2 in pigs from South Africa, and it gives a possible insight into the genetic characteristics and variability of the viral strains presently in circulation within the country. It further emphasizes the need for more stringent measures in curtailing the introduction and spread of transboundary swine pathogens in the country and entire Southern African region.  相似文献   
93.
The clinical role and potential molecular mechanisms of microRNA-449c-5p (miR-449c-5p) in hepatocellular carcinoma (HCC) tissues remains unclear. Combining multiple bioinformatic tools, we studied the miR-449c-5p expression levels in HCC tissues and explored possible target genes and related signaling pathways. First, miR-449c-5p expression data from microarrays provided by publicly available sources were mined and analyzed using various meta-analysis methods. Next, genes that were downregulated after miR-449c-5p mimic transfection into HCC cells were identified, and in silico methods were used to predict potential target genes. Several bioinformatic assessments were also performed to evaluate the possible signaling pathways of miR-449c-5p in HCC. Five microarrays were included in the current study, including GSE98269, GSE64632, GSE74618, GSE40744 and GSE57555. The standard mean difference was 0.44 (0.07–0.80), and the area under the curve was 0.68 (0.63–0.72), as assessed by meta-analyses, which consistently indicated the upregulation of miR-449c-5p in HCC tissues. A total of 2244 genes were downregulated after miR-449c-5p mimic transfection into an HCC cell line, while 5217 target genes were predicted by in silico methods. The overlap of these two gene pools led to a final group of 428 potential target genes of miR-449c-5p. These 428 potential target genes were primarily enriched in the homologous recombination pathway, which includes DNA Polymerase Delta 3 (POLD3). Data mining with Oncomine and the Human Protein Atlas showed a decreasing trend in POLD3 mRNA and protein levels in HCC tissue samples. This evidence suggests that miR-449c-5p could play an essential role in HCC through various pathways and that POLD3 could be a potential miR-449c-5p target. However, these in silico findings should be validated with further experiments.  相似文献   
94.
Polycystic ovary syndrome (PCOS) is one of the most complex and common reproductive and endocrinologic disorders in the child-bearing age of women. Recently, miR-222 were reported to be associated with the etiology of PCOS. However, the function of miR-222 during the pathogenesis of PCOS remains unclear. In the present study, we aimed to investigate the role of miR-222 in PCOS. Firstly, miR-222 expression was examined by quantitative real-time PCR (qRT-PCR) in PCOS. The effects of miR-222 on proliferation, apoptosis and cell cycle in KGN cells were analyzed by CCK-8 assay and flow cytometry analysis, respectively. In addition, bioinformatics analysis was used to predict the target genes of miR-222, and dual-luciferase reporter assay was applied to verified the interaction between miR-222 and p27 Kip1 in KGN cells. Moreover, the expressions of p27 Kip1 in KGN cells treated with miR-222 mimics or miR-222 inhibitor were evaluated by qRT-PCR and western blot assays. The results showed that the expression of miR-222 was remarkably upregulated in PCOS tissues compared with corresponding normal tissues. In the gain-of-function and loss-of-function assays, we revealed that miR-222 mimics significantly promoted cell proliferation, while miR-222 inhibitor induced cell apoptosis and cell cycle arrested. Furthermore, p27 Kip1 was identified as a target gene of miR-222, and could be negatively regulated by miR-222 mimics in KGN cells. In conclusion, our findings suggested that miR-222 may promote the progression of PCOS by targeting p27 Kip1.  相似文献   
95.
目的总结近年来股骨转子间骨折在稳定性重建方面的概念演化与研究进展。方法查阅国内外相关文献并结合自身经验,从股骨转子间骨折的解剖特点、稳定型骨折与不稳定型骨折分类、稳定性复位与不稳定性复位、术中加压初始稳定与术后滑动二次稳定、内固定术后稳定性评估、早期下地站立负重等方面进行总结分析。结果股骨转子间骨折发生于股骨颈干骺端转换区,具有天然的内翻不稳定倾向。骨折复位质量是影响后续内固定物安放的最重要前提因素。判断骨折复位质量有对线和对位两方面,对线采用 Garden 指数;在对位方面,随着皮质对位理念(正性、中性、负性)的提出,特别强调前内侧皮质的相互砥住支撑(解剖、正性),是获得骨折稳定性复位的关键,而不再强调后内侧小转子骨块的作用。术后影像学的稳定性评分为早期下地站立负重提供了量化指标。但术中的前内侧皮质支撑复位,在术后头颈骨块滑动获得二次稳定的过程中,仍有皮质对位丢失现象,需研究其危险因素和防范措施。结论股骨转子间骨折在取得良好对线的基础上,只要获得了前内侧皮质的相互砥住和支撑,并用内固定器械维持住,就获得了术后稳定性。术后稳定性评分优良者,可以安全地早期下地负重、站立行走活动。  相似文献   
96.
97.
Skin sensitivity is a serious problem for many people, and it can be induced by various factors such as UV irradiation, physical and mental stresses, air pollution, dry air and so on. Skin dryness triggered by UV and dry air is one of the most important causes inducing the development of sensitive skin, and it has been reported that oxidative stress contributes to skin dryness. In this study, we investigated whether treatment with 3‐O‐laurylglyceryl ascorbate (VC‐3LG), which is an amphipathic ascorbic acid derivative, can suppress the development of sensitive skin. The results demonstrate that VC‐3LG restores the expression levels of interleukin‐1α, nerve growth factor and matrix metalloprotease‐9 in the dry skin models of reconstructed human epidermal equivalents (RHEEs) and in H2O2‐treated keratinocytes. In addition, VC‐3LG suppresses the dendrite elongation of nerve cells induced in RHEEs by dry skin conditions and by H2O2 treatment of keratinocytes. Therefore, we consider that treatment of the skin with VC‐3LG is an effective approach to improve the development of sensitive skin.  相似文献   
98.
目的总结组织工程半月板支架材料的研究进展。方法查阅近年来国内外组织工程半月板研究相关文献,对支架材料分类和仿生设计进行总结。结果目前组织工程半月板支架材料可大致分为人工合成聚合物、水凝胶、细胞外基质组分和组织衍生材料 4 类。上述材料具有不同特性,使用单一材料制备的支架具有一定缺陷,因此采用多种材料制备复合支架,以期发挥各种材料优势,是目前研究热点。除了材料选择外,材料加工方式也是研究重点。综合材料选择与加工方式,根据半月板形态结构与力学特点进行仿生设计的组织工程半月板支架具有较大潜力。结论目前组织工程半月板支架材料选择较多,但尚无一种材料能完全模拟天然半月板,有待进一步研究。  相似文献   
99.
miRNAs是一类长度约为20~25个核苷酸,参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员,在多种肿瘤中表达异常,其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此,miR-149有望成为新一类抗肿瘤治疗的靶点。  相似文献   
100.
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