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71.
Cognitive decline in aging is a pressing issue associated with significant healthcare costs and deterioration in quality of life. Previously, we reported the successful use of a novel brain-computer interface (BCI) training system in improving symptoms of attention deficit hyperactivity disorder. Here, we examine the feasibility of the BCI system with a new game that incorporates memory training in improving memory and attention in a pilot sample of healthy elderly. This study investigates the safety, usability and acceptability of our BCI system to elderly, and obtains an efficacy estimate to warrant a phase III trial. Thirty-one healthy elderly were randomized into intervention (n = 15) and waitlist control arms (n = 16). Intervention consisted of an 8-week training comprising 24 half-hour sessions. A usability and acceptability questionnaire was administered at the end of training. Safety was investigated by querying users about adverse events after every session. Efficacy of the system was measured by the change of total score from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) before and after training. Feedback on the usability and acceptability questionnaire was positive. No adverse events were reported for all participants across all sessions. Though the median difference in the RBANS change scores between arms was not statistically significant, an effect size of 0.6SD was obtained, which reflects potential clinical utility according to Simon’s randomized phase II trial design. Pooled data from both arms also showed that the median change in total scores pre and post-training was statistically significant (Mdn = 4.0; p<0.001). Specifically, there were significant improvements in immediate memory (p = 0.038), visuospatial/constructional (p = 0.014), attention (p = 0.039), and delayed memory (p<0.001) scores. Our BCI-based system shows promise in improving memory and attention in healthy elderly, and appears to be safe, user-friendly and acceptable to senior users. Given the efficacy signal, a phase III trial is warranted.

Trial Registration

ClinicalTrials.gov NCT01661894  相似文献   
72.
73.
In order to understand the genetic diversity of wild Ussurian pears in China, chloroplast DNA (cpDNA) of 186 wild accessions from 12 populations in Inner Mongolia, Heilongjiang and Jilin Provinces and 51 Chinese and European pear cultivars including Pyrus ussuriensis, Pyrus pyrifolia, Pyrus bretschneideri, Pyrus sinkiangensis and Pyrus communis were investigated. Each accession was classified into one of three types (types A, B and C) based on two large deletions in the hypervariable regions between the accD–psaI and rps16–trnQ genes. Thirty haplotypes were identified by 32 mutations including 17 gaps (in/dels) and 15 base changes. Haplotype network analysis revealed that wild Chinese Ussurian pears could be grouped into subgroup I of type A. A haplotype, Hcp3, in subgroup I detected in Heilongjiang and Jilin Provinces was considered to be a divergent centre in Chinese Ussurian pears. However, the genetic diversity of wild accessions revealed by the two hypervariable regions was quite low. In particular, 98 % of wild Ussurian accessions in Inner Mongolia shared an identical haplotype Hcp1 and are, therefore, monomorphic. In comparison, Chinese pear cultivars were more divergent. These results suggest that the cpDNAs from wild Ussurian pears in Inner Mongolia have specifically differentiated compared to those from pears of other areas. The number of wild Ussurian pears has been decreasing because of desertification and land development, therefore conservation is needed.  相似文献   
74.
潘太健  马瑞  曹春来  黄亮  赵腾  肖拥军 《生物磁学》2013,(24):4634-4637
摘要目的:建立一条新的毕赤酵母表达乙肝表面抗原(HepatitisBantigen,HBsAg)柱层析纯化方法,保持HBsAg结构完整性和提高免疫原性。方法:毕赤酵母发酵料液经过菌体破碎、聚乙二醇沉淀、疏水层析、超滤和凝胶分子筛精纯,收集HBsAg合格样品液适当稀释后加入铝佐荆吸附,制成乙肝疫苗半成品免疫BALB/c小鼠。结果:纯化产物经SDS-PAGE银染鉴定得单一条带,分子量在23kD左右,凝胶成像软件分析纯度超过95%;该纯化方法得到的HBsAg颗粒电镜观察得平均直径为22nm病毒样颗粒,结构较均一完整;自制疫苗免疫小鼠后,其血清抗体水平高于葛兰素史克生产的Engerix—B(安在时),存在显著性差异(P〈0.05)。结论:通过该方法纯化的HBsAg结构完整性良好,疫苗免疫效果优于酵母表达的Engerix—B,纯化路径简单高效,易于放大用于工业化生产。  相似文献   
75.
Optical magnetic responses were demonstrated in subwavelength Ag–MgF2–Ag grating structures for transverse magnetic-polarized light. The subwavelength Ag–MgF2–Ag grating structures were fabricated using e-beam lithography followed by a lift-off process. By fixing the Ag–MgF2–Ag strip dimension, the effect of the stripe width on the magnetic resonances was compared for two different grating pitches. With further reduced grating pitch, we pushed the optical magnetic resonances to near UV (deep blue). Numerical simulations confirmed our experimental observations and were in good agreement with the experimental results.  相似文献   
76.

Objective

To analyze whether urine output and urinalysis results are predictive of survival and neurologic outcomes in patients with non-traumatic out-of-hospital cardiac arrest (OHCA).

Methods

Information was obtained from 1,340 patients with non-traumatic OHCA who had achieved a sustained return of spontaneous circulation (ROSC). Factors that were associated with survival in the post-resuscitative period were evaluated. The association between urine output and fluid challenge in the early resuscitative period was analyzed and compared between the survivors and the non-survivors. The results of the initial urinalysis, including the presence of proteinuria and other findings, were used to evaluate the severity of vascular protein leakage and survival. The association between proteinuria and the neurologic outcomes of the survivors was also analyzed. The clinical features of capillary leakage were examined during the post-resuscitative period.

Results

Of the 1,340 patients, 312 survived. A greater urine output was associated with a higher chance of survival. The initial urine output increased in proportion to the amount of fluid that was administered during early resuscitation in the emergency department for the survivors but not for the non-survivors (p<0.05). In the initial urinalysis, proteinuria was strongly associated with survival, and severe proteinuria indicated significantly poorer neurologic outcomes (p<0.05 for both comparisons). Proteinuria was associated with a risk of developing signs of capillary leakage, including body mass index gain and pitting edema (both p<0.001).

Conclusion

The severity of proteinuria during the early post-resuscitative period was predictive of survival.  相似文献   
77.
Ip  Yuen K.  Hiong  Kum C.  Teng  Joey H. Q.  Boo  Mel V.  Choo  Celine Y. L.  Wong  Wai P.  Chew  Shit F. 《Coral reefs (Online)》2020,39(2):451-465
Coral Reefs - Giant clams flourish in nutrient-poor waters of tropical Indo-Pacific because they live in symbiosis with extracellular dinoflagellates (zooxanthellae) and receive photosynthates from...  相似文献   
78.
Heat shock proteins (HSPs) were known as the molecular chaperones, which play a pivotal role in the protein quality control system, ensuring correct folding of proteins, and facilitating the correct refolding of damaged proteins via the transient interaction with their substrate proteins. They also practice in the regulation of cell cycles and are involved in apoptosis. We found that HspB2 was almost completely silent in pancreatic cancer and few studies investigated the role of HspB2 in cancer cells, particularly in pancreatic cancer. Here, we reported that HspB2 effectively inhibited cell proliferation in Panc-1 cells. Specifically, we demonstrated that HspB2 could combine mut-p53 and change the DNA binding site of mutant p53, subsequently upregulated the expression of RPRM, BAI-1, and TSAP6 which were the downstream genes of wt-p53, participate in mediating downstream responses to p53, including inhibiting cell proliferation and angiogenesis. The main aim of this study is to investigate the relationship between HspB2 and p53, and provide a novel treatment strategy for pancreatic cancer.  相似文献   
79.
80.
The intrasubfamilial classification of Microdontinae Rondani (Diptera: Syrphidae) has been a challenge: until recently more than 300 out of more than 400 valid species names were classified in Microdon Meigen. We present phylogenetic analyses of molecular and morphological characters (both separate and combined) of Microdontinae. The morphological dataset contains 174 characters, scored for 189 taxa (9 outgroup), representing all 43 presently recognized genera and several subgenera and species groups. The molecular dataset, representing 90 ingroup species of 28 genera, comprises sequences of five partitions in total from the mitochondrial gene COI and the nuclear ribosomal genes 18S and 28S. We test the sister‐group relationship of Spheginobaccha with the other Microdontinae, attempt to elucidate phylogenetic relationships within the Microdontinae and discuss uncertainties in the classification of Microdontinae. Trees based on molecular characters alone are poorly resolved, but combined data are better resolved. Support for many deeper nodes is low, and placement of such nodes differs between parsimony and Bayesian analyses. However, Spheginobaccha is recovered as highly supported sister group in both. Both analyses agree on the early branching of Mixogaster, Schizoceratomyia, Afromicrodon and Paramicrodon. The taxonomical rank in relation to the other Syrphidae is discussed briefly. An additional analysis based on morphological characters only, including all 189 taxa, used implied weighting. A range of weighting strengths (k‐values) is applied, chosen such that values of character fit of the resulting trees are divided into regular intervals. Results of this analysis are used for discussing the phylogenetic relationships of genera unrepresented in the molecular dataset.  相似文献   
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