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101.
ObjectiveTo compare important clinical outcomes between early and delayed initiation of antiretroviral therapy (ART) in adults who had a co-infection of human immunodeficiency virus (HIV) and tuberculosis (TB).MethodsWe performed a systematic search for relevant publications on PubMed, EMBASE, and the International Clinical Trials Registry Platform. We included randomized controlled trials (RCTs) that compared early ART initiation (within four weeks after anti-TB treatment starting) and delayed ART initiation (after eight weeks but less than twelve weeks of anti-TB treatment starting) in the course of TB treatment. Pooled estimates with corresponding 95% confidence interval (95%CI) were calculated with random-effects model. Sensitivity analysis was performed to investigate the stability of pooled estimates.ResultsA meta-analysis was evaluated from six RCTs with 2272 participants. Compared to delayed ART initiation, early ART initiation significantly reduces all-cause mortality in HIV-positive patients with TB [incidence rate ratio (IRR) 0.75, 95%CI 0.59 to 0.95; I2 = 0.00%; p = 0.67], even though there is an increased risk for IRD [IRR 2.29, 95%CI 1.81 to 2.91; I22 = 0.00%; p = 0.56]. Additionally, early ART initiation was not associated with an increased risk for grade 3-4 drug-related adverse events [IRR 0.99, 95%CI 0.83 to 1.18; I2 = 0.00%; p = 0.56].ConclusionsAlthough limited evidence, our results provide support for early ART initiation in the course of anti-TB treatment. However, more well-designed cohort or intervention studies are required to further confirm our findings.  相似文献   
102.
BackgroundSeveral immunosuppressive therapeutic regimens are widely used to treat Graves’ ophthalmopathy (GO), including oral glucocorticoids (OGC), intravenous glucocorticoids (IVGC), retrobulbar injections of glucocorticoids (ROGC) and orbital radiotherapy (OR). The priority among these is unknown. This meta-analysis investigated the efficacy and tolerability of the above regimens.MethodsThe PubMed, EMBASE, and Cochrane Library databases and the Chinese Biomedicine Database were searched up to November 18, 2014. Randomized controlled trials (RCTs) comparing monotherapies (OGC, IVGC, ROGC and OR) in patients with moderate-to-severe active GO were selected. The main efficacy measures were the response rate, the standard mean difference (SMD) in the reduction in the clinical activity score (CAS) and the mean difference (MD) in proptosis from baseline to the end of treatment. The main tolerability measure was the risk ratio (RR) for adverse events. The pooled estimates and 95% confidence intervals (95% CIs) were calculated using the RevMan software, version 5.1.ResultsSeven published RCTs involving 328 participants were included in the present meta-analysis, including IVGC versus OGC (3 trials), ROGC versus OGC (3 trials) and OR versus OGC (1 trial). IVGC was more effective than OGC in response rate (RR = 1.48, 95% CI = 1.18–1.87) and had an obvious CAS reduction (SMD = 0.69, 95% CI = 0.13–1.25). IVGC caused fewer adverse events than OGC. ROGC and OGC had no statistically significant difference in response rate (RR = 1.16, 95% CI = 0.94–1.42). OR also did not differ significantly compared with OGC (RR = 0.93, 95% CI = 0.54–1.60). ROGC and OR had fewer adverse events, such as weight gain, compared with OGC.ConclusionsFor patients with GO in the moderate-to-severe active phase, current evidence gave priority to IVGC, which had a statistically significant advantage over OGC and caused fewer adverse events. ROGC and OR did not provide greater efficacy than OGC, although better tolerability and fewer adverse events were shown.  相似文献   
103.
Cancer stem cells (CSCs) can invade and metastasize by epithelial-to-mesenchymal transition (EMT). However, how they escape immune surveillance is unclear. B7H1 is crucial negative co-stimulatory molecule but little information about whether it works in CSCs. Therefore, we determined the expression of B7H1 and EMT-associated markers in colorectal cancer stem-like cells to investigate a possible immunoevasion way of CSCs. We enriched CD133+ colorectal cancer cells which manifested the CSCs-like properties such as higher levels of other stem cell markers Oct-4 and Sox-2, tumor sphere forming ability and more tumorigenic in NOD/SCID mice. These CD133+ cells possess EMT gene expression profile including higher level of Snail, Twist, vimentin, fibronectin and lower level of E-cadherin. Moreover, CD133+ cells in both cell line and colorectal cancer tissues expressed high level of negative co-stimulate molecule B7H1. Furthermore, some B7H1+ cancer cells also showed the characteristic of EMT, indicating EMT cells could escape immune attack during metastasis. B7H1 expression and EMT phenotypes on CSCs indicates a possible immunoevasion way.  相似文献   
104.
105.
Climate and human-driven changes play an important role in regional droughts. Northwest Yunnan Province is a key region for biodiversity conservation in China, and it has experienced severe droughts since the beginning of this century; however, the extent of the contributions from climate and human-driven changes remains unclear. We calculated the ecosystem evapotranspiration (ET) and water yield (WY) of northwest Yunnan Province, China from 2001 to 2013 using meteorological and remote sensing observation data and a Surface Energy Balance System (SEBS) model. Multivariate regression analyses were used to differentiate the contribution of climate and vegetation coverage to ET. The results showed that the annual average vegetation coverage significantly increased over time with a mean of 0.69 in spite of the precipitation fluctuation. Afforestation/reforestation and other management efforts attributed to vegetation coverage increase in NW Yunnan. Both ET and WY considerably fluctuated with the climate factors, which ranged from 623.29 mm to 893.8 mm and –51.88 mm to 384.40 mm over the time period. Spatially, ET in the southeast of NW Yunnan (mainly in Lijiang) increased significantly, which was in line with the spatial trend of vegetation coverage. Multivariate linear regression analysis indicated that climatic factors accounted for 85.18% of the ET variation, while vegetation coverage explained 14.82%. On the other hand, precipitation accounted for 67.5% of the WY. We conclude that the continuous droughts in northwest Yunnan were primarily climatically driven; however, man-made land cover and vegetation changes also increased the vulnerability of local populations to drought. Because of the high proportion of the water yield consumed for subsistence and poor infrastructure for water management, local populations have been highly vulnerable to climate drought conditions. We suggest that conservation of native vegetation and development of water-conserving agricultural practices should be implemented as adaptive strategies to mitigate climate change.  相似文献   
106.

Background

The receptor for advanced glycation endproducts (RAGE) is an oncogenic multidisciplinary trans-membranous receptor, which is overexpressed in multiple human cancers. Recently, it has been shown that RAGE is also involved in carcinogenesis and tumor invasion. In this study, we investigated the expression levels and prognostic value of RAGE in primary gastric cancers (GC).

Methods

We investigated RAGE expression in primary GC and paired normal gastric tissue by real-time quantitative RT-PCR (n = 30) and Western blotting analysis (n = 30). Additionally, we performed immunohistochemistry on 180 paraffin-embedded GC specimens, 69 matched normal specimens.

Results

RAGE was overexpressed in GC compared with the adjacent noncancerous tissues (P<0.001), and higher RAGE expression significantly correlated with the histological grade (P = 0.002), nodal status(P = 0.025), metastasis status(P = 0.002), and American Joint Committee on Cancer stage (P = 0.020). Furthermore, upregulation of RAGE expression is an independent prognostic factor in multivariate analysis using the Cox regression model (P = 0.001).

Conclusions

RAGE Overexpression may be a useful marker to predict GC progression and poor prognosis.  相似文献   
107.
108.

Background  

Application of superparamagnetic iron oxide nanoparticles (SPIOs) as the contrast agent has improved the quality of magnetic resonance (MR) imaging. Low efficiency of loading the commercially available iron oxide nanoparticles into cells and the cytotoxicity of previously formulated complexes limit their usage as the image probe. Here, we formulated new cationic lipid nanoparticles containing SPIOs feasible for in vivo imaging.  相似文献   
109.
东北虎种群的时空动态及其原因分析   总被引:4,自引:0,他引:4  
作者通过对广泛的历史资料的综合分析, 研究了东北虎(Panthera tigris altaica)种群在近一个多世纪以来的时空动态及其原因, 并从景观生态学和可持续性科学的角度对东北虎的保护提出了建议。东北虎是俄罗斯远东、中国东北、蒙古东部以及朝鲜的关键种。近百年以来的多种人为干扰因素使该种群从一个世纪前的近3,000只的历史最高纪录减少到目前约500只的低水平。现存种群主要分布在俄罗斯远东地区Sikhote山脉的一个大生境区域和两个靠近中俄边境孤立的小生境斑块, 少数个体零星分布在中国境内几个小而孤立的生境斑块中。威胁东北虎种群生存的两个最主要因素是捕猎、生境丧失和破碎化。此外, 食物匮乏、战争等因素也对东北虎的生存和繁衍有一定程度的影响。我们建议建立长期监测平台; 禁止盗猎并限制在东北虎潜在栖息地采伐、狩猎以及修筑道路等人类活动; 建立相互连通的保护区域, 特别是建立中国与俄罗斯间跨国界的生态廊道。这些保护措施应该以景观生态学和可持续性科学为指导, 实现空间资源的合理配置和土地利用格局的优化, 同时考虑东北虎种群的生存和当地经济、社会发展的需求, 从而促进实现区域可持续发展的最终目标。  相似文献   
110.
Asialoglycoprotein receptors (ASGP-R) are well known to exist on the mammalian liver, situate on the surface of hepatocyte membrane. Quantitative imaging of asialoglycoprotein receptors could estimate the function of the liver. 99mTc labeled galactosyl-neoglycoalbumin (NGA) and diethylenetriaminepentaacetic acid galactosyl human serum albumin (GSA) have been developed for SPECT imaging and clinical used in Japan. In this study, we labeled the NGA with 18F to get a novel PET tracer [18F]FNGA and evaluated its hepatic-targeting efficacy and pharmacokinetics. Methods: NGA was labeled with 18F by conjugation with N-succinimidyl-4-18F-fluorobenzoate ([18F]SFB) under a slightly basic condition. The in vivo metabolic stability of [18F]FNGA was determined. Ex vivo biodistribution of [18F]FNGA and blocking experiment was investigated in normal mice. MicroPET images were acquired in rat with and without block at 5 min and 15 min after injection of the radiotracer (3.7 MBq/rat), respectively. Results: Starting with 18F Kryptofix 2.2.2./K2CO3 solution, the total reaction time for [18F]FNGA is about 150 min. Typical decay-corrected radiochemical yield is about 8–10%. After rapid purified with HiTrap desalting column, the radiochemical purity of [18F]FNGA was more than 99% determined by radio-HPLC. [18F]FNGA was metabolized to produce [18F]FB-Lys in urine at 30 min. Ex vivo biodistribution in mice showed that the liver accumulated 79.18 ± 7.17% and 13.85 ± 3.10% of the injected dose per gram at 5 and 30 min after injection, respectively. In addition, the hepatic uptake of [18F]FNGA was blocked by pre-injecting free NGA as blocking agent (18.55 ± 2.63%ID/g at 5 min pi), indicating the specific binding to ASGP receptor. MicroPET study obtained quality images of rat at 5 and 15 min post-injection. Conclusion: The novel ASGP receptor tracer [18F]FNGA was synthesized with high radiochemical yield. The promising biological properties of [18F]FNGA afford potential applications for assessment of hepatocyte function in the future. It may provide quantitative information and better resolution which particularly help to the liver surgery.  相似文献   
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