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101.
Wei Bu Gregory M. Hayes Hui Liu Lorraine Gemmell David O. Schmeling Pierce Radecki Fiona Aguilar Peter D. Burbelo Jennifer Woo Henry H. Balfour Jr. Jeffrey I. Cohen 《Clinical and Vaccine Immunology : CVI》2016,23(4):363-369
Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. 相似文献
102.
Yelda Tayyareci M.D. Selen Yurdakul M.D. Gulsah Tayyareci M.D. Yilmaz Nisanci F.E.S.C. Berrin Umman M.D. Zehra Buğra M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(10):1211-1218
Aim: In diabetes mellitus (DM) patients, left ventricular dysfunction is widely evaluated and established by conventional diagnostic methods, whereas right ventricular (RV) function is not as sufficiently evaluated. The aim of this study is to assess the preclinical effects of DM on RV function by using novel Tissue Doppler Imaging (TDI)‐derived indices. Methods: The study included 96 patients with type II DM [60 with DM only and 36 patients with coexisting DM and hypertension (DMHT)] and 40 healthy controls. Conventional parameters and TDI‐derived systolic velocities of tricuspid annulus [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), RV Tei index] were measured. Results: TDI‐derived RV IVA was significantly lower in both DM and DMHT patients compared to controls indicating subclinical impairment in RV systolic function in the study patients (P = 0,0001). However RV IVA was similar in DM and DMHT subgroup supporting RV systolic impairment in DM was independent from HT. In correlation analysis, RV IVA was significantly correlated with the existence of diabetic nephropathy (r =?0,38; P = 0,003), retinopathy (r =?0,35; P = 0,006), insulin resistance (r =?0,52; P = 0,0001). Conclusions: Diabetes is associated with subclinical RV systolic dysfunction, regardless of coexisting hypertension. Tissue Doppler‐derived IVA; is a novel, non‐invasive parameter which may be used in early detection of RV systolic dysfunction in patients with DM. (Echocardiography 2010;27:1211‐1218) 相似文献
103.
BACKGROUND & AIMS: beta-Catenin, a key component of the Wnt pathway, plays an important role in unregulated liver growth in liver tumors, in regulated growth during liver regeneration, and in ex vivo embryonic liver cultures. METHODS: We used developing livers from several stages of gestational development to examine beta-catenin expression, protein-protein interactions, localization, and regulation in prenatal and postnatal livers. RESULTS: Microarray, Northern, and protein analyses showed peak expression of beta-catenin during early liver development at Embryonic day 10 (E10)-E12, followed by a decrease and a complete loss of normal beta-catenin (97-kilodalton species) after E16 through the remaining prenatal period. At the early stages, beta-catenin localized to the cytoplasm and nuclei of resident cells in addition to its normal membranous localization, which was seen at all later stages and in adult liver. Decreases in beta-catenin levels at E14 onward coincided with its decreased gene expression and increased degradation, as seen by an increase in serine 45/threonine 41-phosphorylated beta-catenin and its other negative regulators, such as axin, adenomatous polyposis coli gene product (APC), and glycogen synthase kinase-3 beta. Finally, we showed an intact association of E-cadherin and beta-catenin despite the loss of beta-catenin at E16-E18, owing to the presence of membrane-associated smaller-molecular-weight beta-catenin species. CONCLUSIONS: We also identified a stage-specific expression and regulation of beta-catenin during liver development that might be crucial for physiological liver development. Nuclear and cytoplasmic beta-catenin corresponded to cell proliferation in liver development. Finally, a smaller-molecular-weight species of beta-catenin might be maintaining normal interactions at the membrane. 相似文献
104.
105.
Tao Su Robert A. Spicer Fei-Xiang Wu Alexander Farnsworth Jian Huang Cdric Del Rio Tao Deng Lin Ding Wei-Yu-Dong Deng Yong-Jiang Huang Alice Hughes Lin-Bo Jia Jian-Hua Jin Shu-Feng Li Shui-Qing Liang Jia Liu Xiao-Yan Liu Sarah Sherlock Teresa Spicer Gaurav Srivastava He Tang Paul Valdes Teng-Xiang Wang Mike Widdowson Meng-Xiao Wu Yao-Wu Xing Cong-Li Xu Jian Yang Cong Zhang Shi-Tao Zhang Xin-Wen Zhang Fan Zhao Zhe-Kun Zhou 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):32989
Tibet’s ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to ∼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This “Shangri-La”–like ecosystem experienced monsoon seasonality with a mean annual temperature of ∼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.The Tibetan Plateau, once thought of as entirely the product of the India–Eurasia collision, is known to have had significant complex relief before the arrival of India early in the Paleogene (1–3). This large region, spanning ∼2.5 million km2, is an amalgam of tectonic terranes that impacted Asia long before India’s arrival (4, 5), with each accretion contributing orographic heterogeneity that likely impacted climate in complex ways. During the Paleogene, the Tibetan landscape comprised a high (>4 km) Gangdese mountain range along the southern margin of the Lhasa terrane (2), against which the Himalaya would later rise (6), and a Tanghula upland on the more northerly Qiangtang terrane (7). Separating the Lhasa and Qiangtang blocks is the east–west trending Banggong-Nujiang Suture (BNS), which today hosts several sedimentary basins (e.g., Bangor, Nyima, and Lunpola) where >4 km of Cenozoic sediments have accumulated (8). Although these sediments record the climatic and biotic evolution of central Tibet, their remoteness means fossil collections have been hitherto limited. Recently, we discovered a highly diverse fossil assemblage in the Bangor Basin. These fossils characterize a luxuriant seasonally wet and warm Shangri-La forest that once occupied a deep central Tibetan valley along the BNS, and provide a unique opportunity for understanding the evolutionary history of Asian biodiversity, as well as for quantifying the paleoenvironment of central Tibet.*Details of the topographic evolution of Tibet are still unclear despite decades of investigation (4, 5). Isotopic compositions of carbonates recovered from sediments in some parts of central Tibet have been interpreted in terms of high (>4 km) Paleogene elevations and aridity (9, 10), but those same successions have yielded isolated mammal (11), fish (12), plant (13–18), and biomarker remains (19) more indicative of a low (≤3-km) humid environment, but how low is poorly quantified. Given the complex assembly of Tibet, it is difficult to explain how a plateau might have formed so early and then remained as a surface of low relief during subsequent compression from India (20). Recent evidence from a climate model-mediated interpretation of palm fossils constrains the BNS elevation to below 2.3 km in the Late Paleogene (16), but more precise paleoelevation estimates are required. Further fossil discoveries, especially from earlier in the BNS sedimentary records, would document better the evolution of the Tibetan biota, as well as informing our understanding of the elevation and climate in an area that now occupies the center of the Tibetan Plateau.Our work shows that the BNS hosted a diverse subtropical ecosystem at ∼47 Ma, and this means the area must have been both low and humid. The diversity of the fossil flora allows us to 1) document floristic links to other parts of the Northern Hemisphere, 2) characterize the prevailing paleoclimate, and 3) quantify the elevation at which the vegetation grew. We propose that the “high and dry” central Tibet inferred from some isotope paleoaltimetry (9, 10) reflects a “phantom” elevated paleosurface (20) because fractionation over the bounding mountains allowed only isotopically light moist air to enter the valley, giving a false indication of a high elevation (21). 相似文献
106.
Jiang ZX Peng WJ Li WT Tang F Liu SY Qu XD Wang JH Lu HF 《World journal of gastroenterology : WJG》2008,14(38):5893-5899
AIM: To explore the diffusion gradient b-factor that optimizes both apparent diffusion coefficient (ADC) measurement and contrast-to-noise (CNR) for assessing tumor response to transarterial chemoembolization (TACE) in a rabbit model. METHODS: Twelve New Zealand white rabbits bearing VX2 tumors in the liver were treated with TACE. Diffusion-weighted imaging (DWI) with various b values was performed using the same protocol before and 3 d after treatment with TACE. ADC values and CNR of each tumor pre- and post-treatment with different b factors were analyzed. Correlation between ADC values and extent of necrosis in histological specimens was analyzed by a Pearson's correlation test.RESULTS: The quality of diffusion-weighted images diminished as the b value increased. A substantial decrease in the mean lesion-to-liver CNR was observed on both pre- and post-treatment DW images, the largest difference in CNR pre- and post-treatment was manifested at a b value of 1000 s/mm^2 (P = 0.036 ). The effect of therapy on diffusion early after treatment was shown by a significant increase in ADCs (P = 0.007), especially with large b factors (≥ 600 s/mm^2). The mean percentage of necrotic cells present within the tumor was 76.3%-97.5%. A significant positive correlation was found between ADC values and the extent of necrosis with all b values except for b200, a higher relative coefficient between ADC values and percentage of necrosis was found on DWI with bl000 and b2000 (P = 0.002 and 0.006, respectively). CONCLUSION: An increasing b value of up to 600 s/mm^2 would increase ADC contrast pre- and post-treatment, but decrease image quality. Taking into account both CNR and ADC measurement, diffusion-weighted imaging obtained with a b value of 1000 s/mm^2 is recommended for monitoring early hepatic tumor response to TACE. 相似文献
107.
目的:建立同时测定扑麻滴鼻液中盐酸麻黄碱和马来酸氯苯那敏含量的HPLC方法。方法:采用:PurospherSTAR RP18色谱柱(150 mm×4.6 mm,5μm),以磷酸盐缓冲液(p H 3.0±0.1)-乙腈(82∶18)为流动相,流速为1.0 ml·min-1,在210nm波长处同时检测盐酸麻黄碱和马来酸氯苯那敏,柱温35℃,进样量20μl。结果:盐酸麻黄碱和马来酸氯苯那敏分别在19.81~118.85μg·ml-1和6.21~37.25μg·ml-1浓度范围内线性关系良好,r分别为0.999 6和0.999 8。平均回收率分别为100.39%(RSD=0.69%,n=9)和100.11%(RSD=0.60%,n=9)。结论:该方法快速简便、重复性、准确性好,可用于该制剂中盐酸麻黄碱和马来酸氯苯那敏的含量测定。 相似文献
108.
Xu Yang Zhaoting Bu Maoqin He Yue Lin Yuting Jiang Da Chen Kaibing Liu Jun Zhou 《Medicine》2021,100(3)
This study aimed to compare the effectiveness and safety of reduced-port laparoscopic surgery (RPLS) and conventional multi-port laparoscopic (CMPLS) surgery in the treatment of gastric diseases.The PubMed, Embase, Cochrane Library, Web of Science, and Chinese Biomedical Literature databases were systematically searched for randomized controlled trials, cohort studies, and case control studies on the use of RPLS vs conventional multi-port laparoscopic surgery in treating gastric diseases from their inception until March 10, 2019. The evaluated outcomes were the operative time, blood loss, length of hospital stay, number of dissected lymph nodes, postoperative complications, and conversions. All of these were compared using Stata software version 12.0.A total of 18 studies were included, which involved 2938 patients. In studies referring to the comparison between RPLS and CMPLS in treating gastric diseases, the former showed significantly inferior in terms of operative time (P = .011) and number of dissected lymph nodes (P = .031); but superior results in terms of the estimated blood loss (P = .000) and length of hospital stay (P = .001) than the latter did; however, the rates of postoperative complications (P = .830) and conversions (P = .102) were not statistically significant between the 2 groups.RPLS and CMPLS showed comparable effectiveness and safety in the treatment of gastric diseases in our meta-analysis. Based on the current evidence, we believe that RPLS is an efficacious surgical alternative to CMPLS in the management of gastric diseases because of the shorter hospital stay and reduced blood loss. However, large-scale, well-designed, multicenter studies are needed to further confirm the results of this study. 相似文献
109.
Metabolic Brain Disease - Sepsis-associated encephalopathy (SAE) is a severe complication of sepsis. It has been reported that miR-25-3p is closely related to the development of sepsis. However,... 相似文献
110.
Chen Congying Bu Lingling Liu Huan Rang Yifeng Huang Huiying Xiao Xueman Ou Genghua Liu Chunhong 《Metabolic brain disease》2022,37(5):1451-1463
Metabolic Brain Disease - 1,4-butanediol (1,4-BD) is a known γ-hydroxybutyric acid (GHB) precursor which affects the nervous system after ingestion, leading to uncontrolled behavioral... 相似文献