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71.
Identification of new CRF51_01B in Singapore using full genome analysis of three HIV type 1 isolates
Ng OT Eyzaguirre LM Carr JK Chew KK Lin L Chua A Leo YS Redd AD Quinn TC Laeyendecker O 《AIDS research and human retroviruses》2012,28(5):527-530
A recent HIV-1 molecular epidemiology survey in Singapore identified a novel CRF01_AE/B recombinant form, which accounted for 13 (11.9%) of 109 patient samples. Peripheral blood mononuclear cell DNA from three of these 13 patients was used to generate near full-length sequences to characterize the novel CRF01_AE/B recombinant form. The three isolates had a recombinant structure composed of CRF01_AE and subtype B, and shared identical breakpoints. As the three patients were not epidemiologically linked, this recombinant form has been designated CRF51_01B. Identification of the novel recombinant forms indicates ongoing active HIV-1 transmission in Singapore. 相似文献
72.
目的 评估莫雷西嗪治疗阵发性心房颤动(房颤)患者的有效性和不良反应以及其对房颤负荷的影响.方法 入选阵发性房颤患者212例,给莫雷西嗪单药干预,并随访观察治疗1、6、12个月后房颤的再发情况、负荷量和不良反应.结果 服用莫雷西嗪1、6、12个月房颤再发率仅34%、32%、35%;用药前与用药后1、6、12个月平均心率,最大心率和最小心率均无明显变化,房颤负荷均有明显下降,并未见死亡和恶性室性心律失常.结论 莫雷西嗪可以作为预防、治疗阵发性房颤发作的选择药物之一. 相似文献
73.
Paper-based sensing platforms hold promise in human physiological health monitoring, soft robots, and indoor environment monitoring, owing to their cost effectiveness, flexibility, disposability, and biodegradability. However, most of the existing paper-based sensors require complex fabrication procedures which are also associated with high-cost. Herein, we report a simple yet effective manufacturing process of paper-based carbonaceous sensors based on a laser direct writing (LDW) method. Specifically, carbonaceous pressure, temperature, and humidity sensors on cardboard are developed for human physiological signal monitoring and indoor environment monitoring. Due to the external force induced compaction of the layered carbon flakes, the LDW pressure sensor array has a sensitivity of ∼−0.563 kPa−1, a broad sensing range (0.009–50 kPa), and a high mechanical durability (over 11 000 cycles), all of which are promising for human health monitoring. The LDW-temperature and humidity devices have sensitivities of −0.002/°C and 36.75 fF per %RH, respectively. A prototype is developed using cardboard integrated with temperature and humidity sensors, which not only serves as an ornament to decorate homes but also works as a sensor platform for indoor environment monitoring. Systematic investigation of the LDW manufacturing process, sensing mechanisms, and sensor design and evaluation illustrates the key aspects of carbonaceous sensors.Carbonaceous sensors on cardboard can be used for human health and indoor environment monitoring. 相似文献
74.
Maggie KM Ma Desmond YH Yap Terence PS Yip Sing Leung Lui Wai Kei Lo 《Nephrology (Carlton, Vic.)》2013,18(5):365-368
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture. 相似文献
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78.
Loading rates during walking in adolescents with type II osteonecrosis secondary to pelvic osteotomy 下载免费PDF全文
Ting‐Ming Wang Kuan‐Wen Wu Ching‐Ru Chen Shih‐Wun Hong Tung‐Wu Lu Ken N. Kuo Shier‐Chieg Huang 《Journal of orthopaedic research》2016,34(12):2199-2206
Although Pemberton osteotomy has shown a high success rate even in older children, the occurrence of osteonecrosis (ON) remains one of the most severe complications, leading to premature osteoarthritis. Patients with type II ON are characterized by a valgus deformity of the proximal femur with altered musculoskeletal conditions, affecting the ability to attenuate or sustain the impulsive loading from the ground reaction force. It remains unclear whether these conditions also predispose these patients to harmful impulsive loadings. This study aimed to bridge the gap by measuring the loading rates in the lower limbs during level walking in adolescents who were treated during their infancy for unilateral developmental dysplasia of the hip by a pelvic osteotomy, with or without having developed type II ON. Patients with type II ON were found to display increased loading rates, not only at both the affected and unaffected hip, but also at other joints of the affected limb during level walking when compared to patients without ON changes (p < 0.05). These results suggest that patients with type II ON may be at a higher risk of developing premature hip osteoarthritis that is closely related to abnormal loading rates during gait. It is suggested that regular monitoring of joint loading rates in patients with type II ON is necessary for early identification of damaging loadings, and that early intervention aimed at reducing these loadings should be considered. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2199–2206, 2016. 相似文献
79.
Analysis of the action of euxanthone, a plant-derived compound that stimulates neurite outgrowth 总被引:1,自引:0,他引:1
We have investigated the neurite growth-stimulating properties of euxanthone, a xanthone derivative isolated from the Chinese medicinal plant Polygala caudata. Euxanthone was shown to exert a marked stimulatory action on neurite outgrowth from chick embryo dorsal root ganglia explanted in collagen gels, in the absence of added neurotrophins. It was also shown to promote cell survival in explanted chick embryo ganglia, and to stimulate neurite outgrowth from isolated adult rat primary sensory neurons in vitro. The further finding that euxanthone stimulates neurite outgrowth from explants of chick embryo retina and ventral spinal cord suggests an action on signaling pathways downstream of neuronal receptors for specific neurotrophic factors. Consistent with this, euxanthone did not promote neurite outgrowth from non-transfected PC12 cells, or from PC12 cells transfected with TrkB or TrkC, under conditions in which these cells extended neurites in response to, respectively, the neurotrophins nerve growth factor, brain-derived neurotrophic factor and neurotrophin 3. Western blot analysis of euxanthone-stimulated dorsal root ganglion explants showed that expression of phospho-mitogen-activated protein (MAP) kinase was up-regulated after 1 h of euxanthone-treatment. Inhibition of the MAP kinase pathway using PD98059, a specific inhibitor of MAP kinase kinase, blocked all euxanthone-stimulated neurite outgrowth. However, analysis of phospho-Akt expression indicated that the phosphatidylinositol-3 kinase-Akt pathway, another major signaling pathway engaged by neurotrophins, is not significantly activated by euxanthone. These results suggest that euxanthone promotes neurite outgrowth by selectively activating the MAP kinase pathway. 相似文献
80.
Kuan Chen Junbin He Zhimin Hu Wei Song Liyan Yu Kai Li 《Journal of Asian natural products research》2018,20(7):615-623
AbstractGlycosylation is an effective approach to improve the druggability of natural products by increasing their water solubility. In this work, we report the glycosylation of oleanane-type triterpenoids by a recombinant microbial glycosyltransferase YjiC1. A preliminary screening test indicated YjiC1 exhibited robust capabilities for O-glycosylation of triterpenoids, based on LC/MS analysis. Among the products, two new compounds (2a and 3a), together with a known one (1a), were isolated and characterized. These products exhibited improved water solubility, and 3a showed moderate anti-HIV activities at 100 μM. This reaction provides a facile and efficient approach to synthesize the glucosides of triterpenoids. 相似文献