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81.
Casaclang-Verzosa G Gersh BJ Tsang TS 《Journal of the American College of Cardiology》2008,51(1):1-11
Left atrial (LA) structural and functional remodeling reflects a spectrum of pathophysiological changes that have occurred in response to specific stressors. These changes include alterations at the levels of ionic channels, cellular energy balance, neurohormonal expression, inflammatory response, and physiologic adaptations. There is convincing evidence demonstrating an important pathophysiological association between LA remodeling and atrial fibrillation (AF). Measures that will prevent, attenuate, or halt these processes of LA remodeling may have a major public health impact with respect to the epidemic of AF. In this review, we describe the mechanisms involved in LA remodeling and highlight the existing and potential therapeutic options for its reversal, and implications for AF development. 相似文献
82.
Patrick C.Y. Woo Susanna K.P. Lau Ulrich Wernery Emily Y.M. Wong Alan K.L. Tsang Bobby Johnson Cyril C.Y. Yip Candy C.Y. Lau Saritha Sivakumar Jian-Piao Cai Rachel Y.Y. Fan Kwok-Hung Chan Ringu Mareena Kwok-Yung Yuen 《Emerging infectious diseases》2014,20(4):560-572
In 2013, a novel betacoronavirus was identified in fecal samples from dromedaries in Dubai, United Arab Emirates. Antibodies against the recombinant nucleocapsid protein of the virus, which we named dromedary camel coronavirus (DcCoV) UAE-HKU23, were detected in 52% of 59 dromedary serum samples tested. In an analysis of 3 complete DcCoV UAE-HKU23 genomes, we identified the virus as a betacoronavirus in lineage A1. The DcCoV UAE-HKU23 genome has G+C contents; a general preference for G/C in the third position of codons; a cleavage site for spike protein; and a membrane protein of similar length to that of other betacoronavirus A1 members, to which DcCoV UAE-HKU23 is phylogenetically closely related. Along with this coronavirus, viruses of at least 8 other families have been found to infect camels. Because camels have a close association with humans, continuous surveillance should be conducted to understand the potential for virus emergence in camels and for virus transmission to humans. 相似文献
83.
Patrick C.Y. Woo Susanna K.P. Lau Jade L.L. Teng Alan K. L. Tsang Marina Joseph Emily Y.M. Wong Ying Tang Saritha Sivakumar Jun Xie Ru Bai Renate Wernery Ulrich Wernery Kwok-Yung Yuen 《Emerging infectious diseases》2014,20(6):1044-1048
In a molecular epidemiology study of hepatitis E virus (HEV) in dromedaries in Dubai, United Arab Emirates, HEV was detected in fecal samples from 3 camels. Complete genome sequencing of 2 strains showed >20% overall nucleotide difference to known HEVs. Comparative genomic and phylogenetic analyses revealed a previously unrecognized HEV genotype.Hepatitis E virus (HEV) belongs to the family Hepeviridae and genus Hepevirus. Among humans worldwide, HEV is the most common cause of acute viral hepatitis. The disease is generally self-limiting, but mortality rates are high among pregnant women and young infants. Chronic HEV infection is a problem for immunocompromised patients, such as those who have received a solid organ transplant and those with HIV infection. In addition to humans, HEV has been found in the other mammals: pigs, boar, deer, rodents, ferrets, rabbits, mongoose, bats, cattle, sheep, foxes, minks, and horses (1–3). Among the 4 known HEV genotypes, HEV1 and HEV2 infect only humans; whereas, HEV3 and HEV4 can infect humans, pigs, and other mammals. Human infections with HEV3 and HEV4 have been associated with consumption of raw or undercooked pork or game meat (4). Traditionally, HEV infection is mainly transmitted through water contaminated with infected feces. Since water supplies and sanitary infrastructures have been improved, animals have become a major source of human HEV infection. We detected HEV in fecal samples from dromedary camels in the Middle East. 相似文献
84.
Introduction
Hip fractures remain the most common orthopaedic injury requiring hospital admission. Failed surgery for any cause carries a higher morbidity, mortality, and healthcare-related cost. The aims of this study were to determine risk factors for surgical complications of hip fracture surgery, when they occurred and their effect on mortality.Patients and methods
From a prospectively collected consecutive database of 795 hip fractures admitted between July 2007 and June 2008, all surgical and non-surgical complications were identified as well as re-operation for any cause and mortality in the 4 years since surgery.Results
Fifty-five (6.9%) patients were found to have developed a surgical complication requiring further intervention. Risk factors included younger age, smoking and cannulated screw fixation. Cannulated screw fixation was associated with a 30.9% rate of re-operation. Post-operative medical complication occurred in 21.8%. It was associated with a 78.5% mortality at 4 years with a median time to mortality of 58 days (95% CI 0–120 days).Conclusions
Mechanical failure was the most common reason for cannulated screw re-operation. Hip hemiarthroplasty most commonly failed by infection. Inter-trochanteric and sub-trochanteric fracture fixation had very low failure rates. Post-operative medical complications, but not surgical complications, were associated with a higher mortality rate. 相似文献85.
Frank J. Molnar MSc MDCM Sophiya Benjamin MBBS MD Stacey A. Hawkins BA MA CPG PhD Student Melanie Briscoe OT Sabeen Ehsan MBBS MD MHI 《Journal of the American Geriatrics Society》2020,68(10):2207-2213
Every year, millions of patients worldwide undergo cognitive testing. Unfortunately, new barriers to the use of free open access cognitive screening tools have arisen over time, making accessibility of tools unstable. This article is in follow-up to an editorial discussing alternative cognitive screening tools for those who cannot afford the costs of the Mini-Mental State Examination and Montreal Cognitive Assessment (see www.dementiascreen.ca ). The current article outlines an emerging disruptive “free-to-fee” cycle where free open access cognitive screening tools are integrated into clinical practice and guidelines, where fees are then levied for the use of the tools, resulting in clinicians moving on to other tools. This article provides recommendations on means to break this cycle, including the development of tool kits of valid cognitive screening tools that authors have contracted not to charge for (i.e., have agreed to keep free open access). The PRACTICAL.1 Criteria ( PRACTI cing C linician A ccessibility and L ogistical Criteria Version 1 ) are introduced to help clinicians select from validated cognitive screening tools, considering barriers and facilitators, such as whether the cognitive screening tools are easy to score and free of cost. It is suggested that future systematic reviews embed the PRACTICAL.1 criteria, or refined future versions, as part of the standard of review. Methodological issues, the need for open access training to insure proper use of cognitive screening tools, and the need to anticipate growing ethnolinguistic diversity by developing tools that are less sensitive to educational, cultural, and linguistic bias are discussed in this opinion piece. J Am Geriatr Soc 68:2207–2213, 2020. 相似文献
86.
87.
Peter Tsang Geoffrey J. Gorse Cynthia B. Strout Malcolm Sperling David P. Greenberg Ayca Ozol-Godfrey Carlos DiazGranados Victoria Landolfi 《Vaccine》2014
We conducted a randomized, controlled, multicenter, phase II study to evaluate the immunogenicity and safety of an investigational intradermal (ID) trivalent influenza vaccine (TIV) and a high-dose (HD) intramuscular (IM) TIV in older adults (≥65 years of age). Older adult subjects were immunized with ID vaccine containing either 15 μg hemagglutinin (HA)/strain (n = 636) or 21 μg HA/strain (n = 634), with HD IM vaccine containing 60 μg HA/strain (n = 320), or with standard-dose (SD) IM vaccine (Fluzone®; 15 μg HA/strain; n = 319). For comparison, younger adults (18–49 years of age) were immunized with SD IM vaccine. In older adults, post-vaccination geometric mean titers induced by the ID vaccines were superior to those induced by the SD IM vaccine for the A/H1N1 and A/H3N2 strains and non-inferior for the B strain. Seroconversion rates induced by the ID vaccines were superior to those induced by the SD IM vaccine in older adults for the A/H1N1 and B strains and non-inferior for the A/H3N2 strain. Results did not differ significantly for the two ID vaccine dosages. Post-vaccination geometric mean titers, seroconversion rates, and most seroprotection rates were significantly higher in HD vaccine recipients than in older adult recipients of the SD IM or ID vaccines and, for most measures, were comparable to those of younger adult SD IM vaccine recipients. Injection-site reactions, but not systemic reactions or unsolicited adverse events, were more common with the ID vaccines than with the IM vaccines. No treatment-related serious adverse events were reported. This study demonstrated that: (1) the ID and HD vaccines were well-tolerated and more immunogenic than the SD IM vaccine in older adults; (2) the HD vaccine was more immunogenic than the ID vaccines in older adults; and (3) the HD vaccine in older adults and the SD IM vaccine in younger adults elicited comparable antibody responses (ClinicalTrials.gov identifier no.: NCT00551031). 相似文献
88.
89.
The Chinese version of the General Health Questionnaire (GHQ-30) was administered to 381 parents of preschool mentally handicapped children, along with other instruments that assessed their stress, mental health, coping styles, and care-giving patterns. The GHQ-30 was found to have high internal consistency as a scale and high item-total correlations for most of the items. Factor analysis with a four-factor solution showed that four factors were abstracted from the scale, namely, anxiety, depression, interpersonal dysfunctioning, and inadequate coping. It also was found that the factors extracted could be reproduced reliably in two random subsamples and that the factor structure derived from the present sample corresponds to the previously reported data on the dimensionality of the Chinese GHQ-30. 相似文献
90.
Yunbi Ni Julia Y Tsang Yan Shao Ivan K Poon Fiona Tam Ka-Ho Shea Gary M Tse 《The oncologist》2022,27(4):e313
BackgroundPD-L1 has been used as a biomarker to select patients for treatment of PD-1/PD-L1 inhibitors.Materials and MethodsIn this study, we assessed the clinicopathological features of breast cancers that are associated with PD-L1 expression, as well as its relationship with other immune components and its prognostic significance.ResultsTotally 1752 cases were included in this cohort. PD-L1 expression in tumor-infiltrating immune cells (PD-L1-IC) expression and in tumor cells (PD-L1-TC) expression were identified in 34.2% and 10.1% of cases, respectively, and they showed a positive correlation with higher tumor grade, morphological apocrine features, presence of necrosis, and higher stromal tumor-infiltrating lymphocytes (sTIL). PD-L1-IC and PD-L1-TC expression correlated positively with each other, and both of them were negatively associated with estrogen receptor and progesterone receptor and positively associated with Ki67, HER2, EGFR, p63, and p-cadherin. In survival analysis, PD-L1-IC expression was associated with better disease-free survival (DFS) and breast cancer-specific survival (BCSS) in HER2-overexpressed (HER2-OE) cancers and high–grade luminal B cancers. In triple–negative breast cancers (TNBC) and HER2–OE cancers, compared with sTIL low PD-L1-IC negative cases, sTIL high cases showed significantly better DFS independent of PD-L1-IC status. sTIL low PD-L1-IC positive cases also demonstrated a better DFS in HER2–OE cancers. In high–grade luminal B cancers, sTIL high PD-L1-IC positive cases showed the best BCSS.ConclusionThe data suggested that the combining analysis of sTIL and PD-L1-IC expression refined the prognostication of breast cancer subtypes. Cases with high TIL and PD-LI-IC expression appear to be more immune active. 相似文献