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Although the Davila-Sierra mitral valve prosthesis was removed from the market nearly a decade ago, a number of patients still have this valve in place. We recently studied the echocardiographic features of a malfunctioning Davila-Sierra mitral valve prosthesis. Abnormalities that suggested improper functioning of the prosthesis included a markedly delayed poppet opening and an early diastolic hump believed to represent motion of the mitral annulus. Previously described echocardiographic indications of dys-function were not observed in our patient. We report the first known echocardiographic evaluation of a Davila-Sierra prosthesis. 相似文献
63.
Wijayanti Nastiti Gazali Faris Muhammad Supriyati Endah Hakim Mohamad Saifudin Arguni Eggi Daniwijaya Marselinus Edwin Widyanto Nuryastuti Titik Nuhamunada Matin Nabilla Rahma Haryana Sofia Mubarika Wibawa Tri 《International microbiology》2022,25(3):531-540
International Microbiology - Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new virus responsible for the COVID-19 pandemic. The emergence of the new SARS-CoV-2 has been... 相似文献
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Hoang Vu Phan Quoc Viet Nguyen Quang Tri Truong Tien Van Truong Hoon Cheol Park Nam Seo Goo Doyoung Byun Min Jun Kim 《仿生工程学报(英文版)》2012,9(4):391-401
We briefly summarized how to design and fabricate an insect-mimicking flapping-wing system and demonstrate how to implement inherent pitching stability for stable vertical takeoff.The effect of relative locations of the Center of Gravity (CG) and the mean Aerodynamic Center (AC) on vertical flight was theoretically examined through static force balance consideration.We conducted a series of vertical takeoff tests in which the location of the mean AC was determined using an unsteady Blade Element Theory (BET) previously developed by the authors.Sequential images were captured during the takeoff tests using a high-speed camera.The results demonstrated that inherent pitching stability for vertical takeoff can be achieved by controlling the relative position between the CG and the mean AC of the flapping system. 相似文献
66.
Comparative proteomics of Cannabis sativa plant tissues. 总被引:4,自引:0,他引:4
Tri J Raharjo Ivy Widjaja Sittiruk Roytrakul Robert Verpoorte 《Journal of biomolecular techniques》2004,15(2):97-106
Comparative proteomics of leaves, flowers, and glands of Cannabis sativa have been used to identify specific tissue-expressed proteins. These tissues have significantly different levels of cannabinoids. Cannabinoids accumulate primarily in the glands but can also be found in flowers and leaves. Proteins extracted from glands, flowers, and leaves were separated using two-dimensional gel electrophoresis. Over 800 protein spots were reproducibly resolved in the two-dimensional gels from leaves and flowers. The patterns of the gels were different and little correlation among the proteins could be observed. Some proteins that were only expressed in flowers were chosen for identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and peptide mass fingerprint database searching. Flower and gland proteomes were also compared, with the finding that less then half of the proteins expressed in flowers were also expressed in glands. Some selected gland protein spots were identified: F1D9.26-unknown prot. (Arabidopsis thaliana), phospholipase D beta 1 isoform 1a (Gossypium hirsutum), and PG1 (Hordeum vulgare). Western blotting was employed to identify a polyketide synthase, an enzyme believed to be involved in cannabinoid biosynthesis, resulting in detection of a single protein. 相似文献
67.
Three‐dimensional microscale modelling of CO2 transport and light propagation in tomato leaves enlightens photosynthesis 下载免费PDF全文
Quang Tri Ho Herman N. C. Berghuijs Rodrigo Watté Pieter Verboven Els Herremans Xinyou Yin Moges A. Retta Ben Aernouts Wouter Saeys Lukas Helfen Graham D. Farquhar Paul C. Struik Bart M. Nicolaï 《Plant, cell & environment》2016,39(1):50-61
We present a combined three‐dimensional (3‐D) model of light propagation, CO2 diffusion and photosynthesis in tomato (Solanum lycopersicum L.) leaves. The model incorporates a geometrical representation of the actual leaf microstructure that we obtained with synchrotron radiation X‐ray laminography, and was evaluated using measurements of gas exchange and leaf optical properties. The combination of the 3‐D microstructure of leaf tissue and chloroplast movement induced by changes in light intensity affects the simulated CO2 transport within the leaf. The model predicts extensive reassimilation of CO2 produced by respiration and photorespiration. Simulations also suggest that carbonic anhydrase could enhance photosynthesis at low CO2 levels but had little impact on photosynthesis at high CO2 levels. The model confirms that scaling of photosynthetic capacity with absorbed light would improve efficiency of CO2 fixation in the leaf, especially at low light intensity. 相似文献
68.
Woodruff MA Rath SN Susanto E Haupt LM Hutmacher DW Nurcombe V Cool SM 《Journal of molecular histology》2007,38(5):425-433
This paper explores the potential therapeutic role of the naturally occurring sugar heparan sulfate (HS) for the augmentation
of bone repair. Scaffolds comprising fibrin glue loaded with 5 μg of embryonically derived HS were assessed, firstly as a
release-reservoir, and secondly as a scaffold to stimulate bone regeneration in a critical size rat cranial defect. We show
HS-loaded scaffolds have a uniform distribution of HS, which was readily released with a typical burst phase, quickly followed
by a prolonged delivery lasting several days. Importantly, the released HS contributed to improved wound healing over a 3-month
period as determined by microcomputed tomography (μCT) scanning, histology, histomorphometry, and PCR for osteogenic markers.
In all cases, only minimal healing was observed after 1 and 3 months in the absence of HS. In contrast, marked healing was
observed by 3 months following HS treatment, with nearly full closure of the defect site. PCR analysis showed significant
increases in the gene expression of the osteogenic markers Runx2, alkaline phosphatase, and osteopontin in the heparin sulfate
group compared with controls. These results further emphasize the important role HS plays in augmenting wound healing, and
its successful delivery in a hydrogel provides a novel alternative to autologous bone graft and growth factor-based therapies.
Maria Ann Woodruff and Subha Narayan Rath contributed equally to this work. 相似文献
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The Vietnam Initiative on Zoonotic Infections (VIZIONS): A Strategic Approach to Studying Emerging Zoonotic Infectious Diseases 总被引:1,自引:0,他引:1
Maia A. Rabaa Ngo Tri Tue Tran My Phuc Juan Carrique-Mas Karen Saylors Matthew Cotten Juliet E. Bryant Ho Dang Trung Nghia Nguyen Van Cuong Hong Anh Pham Alessandra Berto Voong Vinh Phat Tran Thi Ngoc Dung Long Hoang Bao Ngo Thi Hoa Heiman Wertheim Behzad Nadjm Corina Monagin H. Rogier van Doorn Motiur Rahman My Phan Vu Tra James I. Campbell Maciej F. Boni Pham Thi Thanh Tam Lia van der Hoek Peter Simmonds Andrew Rambaut Tran Khanh Toan Nguyen Van Vinh Chau Tran Tinh Hien Nathan Wolfe Jeremy J. Farrar Guy Thwaites Paul Kellam Mark E. J. Woolhouse Stephen Baker 《EcoHealth》2015,12(4):726-735