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951.
952.
正代谢相关脂肪性肝病(Metabolic-dysfunction-associated fatty liver disease,MAFLD)的明确诊断至今仍需排除过量饮酒等其他原因所导致的慢性肝病~([1])。然而,鉴于对MAFLD发病机制的深入理解及其患病率的不断攀升,诊断该病需要有"肯定性标准"。近来,由22个国家30位专家组成的国际专家小组发布的有关MAFLD新定义的国际专家共识声明,既全面又简便地诊断MAFLD,该标准与饮酒量无关,可应用于任何临床情境~([2])。新的诊断标准基于肝活检组织学或影像学甚至血液生物标志物检查提示存在脂肪肝,同时满足以下三项条件之一:超重/肥胖、2型糖尿病、代谢功能障碍。专家组建议,取消当前有无脂肪性肝炎的二分类法则,建议根据肝脏炎症活动度和肝纤维化程度进行MAFLD炎症程度评估和危险分层管理。该小组还提出了MAFLD相关肝硬化的诊断标准,以及其他原因相关脂肪性肝病的概念框架。最后,新的专家共识还明确了诊断标准与临床研究和临床试验纳入标准的区别。  相似文献   
953.
TRK‐100STP, a sustained‐release preparation of the orally active prostacyclin analogue beraprost sodium, targets renal hypoxia. This study aimed to show the superiority of TRK‐100STP over placebos in patients with chronic kidney disease (with either primary glomerular disease or nephrosclerosis) to determine the recommended dose. CASSIOPEIR (Chronic Renal Failure Asian Study with Oral PGI2 Derivative for Evaluating Improvement of Renal Function) was a randomized, double‐blind, placebo‐controlled study conducted at 160 sites in seven Asia‐Pacific countries and regions. Eligible patients (n = 892) were randomized to TRK‐100STP 120, 240 μg, or placebo for a treatment period of up to 4 years. The primary efficacy endpoint was time to first occurrence of a renal composite: doubling of serum creatinine or occurrence of end‐stage renal disease. No significant differences were observed in composite endpoints between TRK‐100STP and placebo (P = 0.5674). Hazard ratios (95% CI) in the TRK‐100STP 120 and 240 μg vs. placebo groups were 0.98 (0.78, 1.22) and 0.91 (0.72, 1.14), respectively. The overall incidence of adverse events and adverse drug reactions was comparable between treatment arms.  相似文献   
954.
955.
We report a rare case of antisynthase syndrome (ASS) complicated with Kaposi sarcoma, analyze its clinical characteristics, and review the literature on the topic. An 80‐year‐old male patient developed fever, cough, and shortness of breath. Lung high‐resolution computed tomography showed nonspecific interstitial pneumonia in both lungs, and myositis antibody examination showed strongly positive anti‐alanyl tRNA synthase (PL‐12) antibodies. Based on these findings, the patient was diagnosed with ASS. After full‐dose glucocorticoid treatment, the symptoms of fever and cough were relieved, but skin thickening and pigmentation in both feet were observed. We confirmed Kaposi sarcoma through skin pathology and immunohistochemical examination of the bottom of the patient's feet, and the patient was transferred to a cancer hospital for radiotherapy. ASS presents with some skin changes that might lead to misdiagnosis. ASS complicated with Kaposi sarcoma is rare, and to our knowledge, this is the first case reported in China.  相似文献   
956.
BackgroundTranscervical esophagectomy is a less invasive procedure performed within mediastinum. However, the mediastinum offers limited surgical space and the surgery via this route differs from conventional minimally invasive esophagectomy. Therefore, the physiological study of this surgical approach on an animal model would be necessary before the procedure gained more popularity.MethodsWe conducted transcervical minimally invasive esophagectomy on animal model (swine) under CO2 pneumomediastinum. The hemodynamic parameters were monitored using float catheter cannulated via right jugular vein. At different anatomical level (the upper, middle, and lower thoracic part of the animal esophagus), increased artificial pneumomediastinal pressures (0, 4, 8, 12, and 16 mmHg) were consecutively allocated to record the intra-operative changes of blood pressure, cardiac output (CO), central venous pressure (CVP), pulmonary artery pressure (PAP) and extravascular lung water (EVLW). Meanwhile, the surgical field under different pneumomediastinum pressure was recorded and balanced with animals’ hemodynamic changes to determine the optimal pressure for transcervical minimally invasive esophagectomy.ResultsThe animal procedures were accomplished without conversions. During the upper thoracic stage, increased CO2 pressures did not lead to significant changes in hemodynamic parameters including the blood pressure, CO, CVP, PAP or the level of EVLW. During the middle thoracic stage, pneumomediastinum under 4–12 mmHg did not lead to significant changes in hemodynamic parameters. However, pneumomediastinum at 16 mmHg resulted in lower CO (P=0.038) when compared to 0–12 mmHg. During lower thoracic stage, as the pneumomediastinum pressures increased from 0 to 16 mmHg, significant decrease in CO (P=0.022), and increase in CVP (P=0.036) was recorded. In compared to 4 mmHg pneumomediastinum, the surgical field under 8–16 mmHg artificial CO2 pneumomediastinum was suitable for mediastinal manipulation.ConclusionsDuring transcervical minimally invasive esophagectomy on animal model, the mobilization of swine thoracic esophagus with optimal pneumomediastinum pressure 8–12 mmHg is safe and effective based on hemodynamic analysis.  相似文献   
957.
目的检测钠尿肽受体(NPR)在不同年龄小鼠视网膜内的表达,探讨其在视网膜发育过程中的作用。方法收集从受孕16日(E16)到出生90日(P90)小鼠眼球标本共127只,对NPR-A进行免疫荧光检测。结果NPR-A广泛存在于视网膜神经元中,例如,在外核层,NPR-A于P7开始高表达在视锥、视杆细胞内、外突起上,于P14减弱,P30之后持续稳定弱表达;在内核层,从P7开始NPR-A持续弱表达在双极细胞的突起中,而在水平细胞中未见NPR-A表达;在神经节细胞层,NPR-A于E16开始高表达在神经节细胞胞体中,P14明显减弱,而在神经纤维层,即神经节细胞的轴突中,NPR-A从胚胎期至成年持续高表达;在外网状层和内网状层,NPR-A于P14均高表达,但于P30之后逐渐减弱。此外,NPR-A还广泛的存在于Müller细胞的突起中。结论 NPR-A参与了视网膜的发育,可能是小鼠视网膜神经元发育过程中的关键分子,并对Müller细胞的功能活动起着重要的调节作用。  相似文献   
958.
Sixty-two strains of avian infectious bronchitis virus (IBV) were isolated from diseased chickens at different farms in southern China during 2011–2012, and 66.1 % of the isolated strains were associated with typical nephritis. Analysis of the S1 gene sequences amplified from the 62 isolated strains together with 40 reference strains published in Genbank showed nucleotide homologies ranging from 63.5 to 99.9 % and amino acid homologies ranging from 57.9 to 100 %. Phylogenetic analysis revealed that all Chinese IBV strains were clustered into six distinct genetic groups (I–VI). Most of the isolated strains belonged to group I, and the isolation of group V strains was increased compared with an earlier period of surveillance. Current vaccine strains used in China (H120, H52, W93, and Ma5) formed the group Mass which is evolutionarily distant from Chinese isolates. Alignment of S1 amino acid sequences revealed polymorphic and diverse substitutions, insertions, and deletions, and the S1 protein of major pandemic strains contained 540 amino acids with a cleavage site sequence of HRRRR or RRF(L/S)RR. Further analysis showed that recombination events formed a new subgroup. Taken together, these findings suggest that various IBV variants were co-circulating and undergoing genetic evolution in southern China during the observation period. Therefore, long-term continuing surveillance is significantly important for prevention and control of IBV infection.  相似文献   
959.
The rabies virus (RABV) G protein is the primary contributor to the pathogenicity and protective immunity of RABV. In this study, we generated a recombinant rCVS-11-G strain containing two copies of the G protein derived from the pathogenic wild-type (wt) CVS-11 strain and based on its infectious clone. Compared with the wtCVS-11 strain, the rCVS-11-G strain possessed a larger virion and 1.4-fold more G protein, but it exhibited a similar growth property to the rCVS-11 strain, including passaging stability in vitro. qPCR results showed that the two G genes were over-expressed in BHK-21 cells infected with the rCVS-11-G strain. However, the rCVS-11-G strain presented an 80 % lower LD50 than the wtCVS-11 strain when intracranially (i.c.) inoculated in adult mice. Adult mice that were either intracranially (i.c.) or intramuscularly (i.m.) inoculated with rCVS-11-G strain developed more acute neurological symptoms and greater mortality than those inoculated with the wtCVS-11 strain. Furthermore, the rCVS-11-G strain was more easily and rapidly taken up by neuroblastoma cells. These data indicated that the rCVS-11-G strain might have increased neurotropism because of the over-expression of the pathogenic G protein. The inactivated rCVS-11-G strain induced significantly higher levels of virus neutralization antibodies and provided better protection from street rabies virus challenge in mice. Therefore, the rCVS-11-G strain may be a promising inactivated vaccine strain due to its better immunogenicity.  相似文献   
960.
Three strains of porcine epidemic diarrhea virus (PEDV) were isolated from dead or diseased pigs at different swine farms in Guangdong during 2011–2013, and their S genes were sequenced. In the same period, seven PEDV strains were also isolated in Guangdong by other laboratories. The spike sequences of 10 Guangdong isolates were compared with vaccine strains and reference pathogenic isolates using six bioinformatics tools. The results revealed that 10 Guangdong strains, excluding strain GDS03, had distinct characteristics in terms of primary structure, secondary structure, high-specificity N-glycosylation sites, potential phosphorylation sites, and palmitoylation sites. Phylogenetic analysis also confirmed these findings and revealed that all PEDV strains were clustered into three distinct groups. Ten Guangdong strains, not including GDS03, belong to Group 1, whereas four vaccine strains and GDS03 belong to Group 3, which is evolutionarily distant from Group 1. Alignment analysis of the neutralizing region amino acid sequences indicated that the amino acid substitutions of Y/D766S, T549S, and G594S that are present in the Guangdong strains, not including GDS03, were a sign of predominant genetic changes among the isolated strains. GDS03 is closely related to the 83P-5 vaccine strain, which suggests that it might represent re-isolation of the vaccine strain or vaccine variants. Taken together, these results indicate that there have been predominant new strains circulating in Guangdong from 2011 to 2013, and the circulating PEDV strains have a genetic composition that is distant from reference strains, especially the vaccine strains; however, the vaccinations might also provide some level of cross-protection, as there have been no changes in the neutralizing epitopes of SS2 and 2C10. This explains why there have been constant but infrequent outbreaks recently in comparison to late 2010 in which PEDV outbreaks were more frequent and severe. In addition, the USA-Colorado-2013 strain had the same amino acid substitutions in the neutralizing regions as the Guangdong strains except GDS03, which suggests that the information and strategies in this study may play role in PEDV variant research in other countries.  相似文献   
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