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31.
Adrian Baranchuk Marwan M. Refaat Kristen K. Patton Mina K. Chung Kousik Krishnan Valentina Kutyifa Gaurav Upadhyay John D. Fisher Dhanunjaya R. Lakkireddy 《Journal of the American College of Cardiology》2018,71(11):1284-1288
Medical devices have been targets of hacking for over a decade, and this cybersecurity issue has affected many types of medical devices. Lately, the potential for hacking of cardiac devices (pacemakers and defibrillators) claimed the attention of the media, patients, and health care providers. This is a burgeoning problem that our newly electronically connected world faces. In this paper from the Electrophysiology Section Council, we briefly discuss various aspects of this relatively new threat in light of recent incidents involving the potential for hacking of cardiac devices. We explore the possible risks for the patients and the effect of device reconfiguration in an attempt to thwart cybersecurity threats. We provide an outline of what can be done to improve cybersecurity from the standpoint of the manufacturer, government, professional societies, physician, and patient. 相似文献
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Koichi Hiraoka Kyudo Igawa Mina Kashiwagi Chisato Nakahara Yuki Oshima Yu Takakura 《Laterality》2018,23(1):51-66
The objective of the present study was to investigate whether the stop and go processes of the motor response are asymmetrical and whether the asymmetries are dependent on handedness and the response selection process that is engaged. Both right-handed and left-handed participants abducted either the left or right index finger in response to an imperative cue in the choice reaction time (choice RT) or the simple RT task. A stop cue was presented after the imperative cue with a probability of .25. When the stop cue was presented, the participants withheld the prepared response. On the choice RT task, left-handed participants had significantly shorter RT and stop signal reaction time (SSRT) with the left versus the right hand, whereas right-handers showed no difference between hands on either measure. In the simple RT task, the RT and SSRT were not significantly different between the groups or the response sides. These results indicate that both the stop and go processes of the prepared left-hand response are completed earlier than those of the right-hand response in left-handed individuals when the stimulus-response process involves a response selection process. 相似文献
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Robert R. Young Chad M. Thompson Harshini R. Dinesdurage Reem H. Elbekai Mina Suh Annette C. Rohr Deborah M. Proctor 《Environmental and molecular mutagenesis》2015,56(7):629-636
The Big Blue® (BB) in vivo mutation assay uses transgenic rodents to measure treatment‐induced mutations in virtually any tissue. The BB assay can be conducted in rats or mice and is ideal for investigating tissue‐specific mutagenic mode of action of tumor induction. Some tissues such as oral mucosa have not been thoroughly studied. Due to the small quantity and cartilaginous nature of oral cavity tissues, development of special prosection and DNA isolation methods was required to permit robust analysis of mutations in these tissues. Improved surgical methods permitted collection of adequate and reproducible quantities of tissue (~45 mg gingiva/buccal and ~30 mg gingiva/palate). Optimized DNA isolation methods included use of liquid nitrogen pulverization, homogenization, nuclei pelleting, digestion, and phenol/chloroform extraction, to yield sufficient quantities of DNA from these tissues. In preliminary optimization work, mutant frequency (MF) in tongue and gingiva was increased in rats exposed to the promutagen, benzo[a]pyrene, and the direct mutagen, N‐ethyl‐N‐nitrosourea. The oral cavity carcinogen, 4‐nitroquinoline‐1‐oxide (4‐NQO; 10 ppm in drinking water; 28 days), was qualified as a positive control for mutagenesis in oral tissues since it caused significant increases in cII MFs in gingiva/palate (50.2‐fold) and gingiva/buccal tissues (21.3‐fold), but not in liver or bone marrow (0.9‐ and 1.4‐fold, respectively). These results are consistent with the observation that 4‐NQO primarily induces tumors in oral cavity. Results also demonstrate the utility of the BB rat mutation assay and optimized methods for investigation of oral cavity mutagenicity, and by extension, analysis of other small and cartilaginous tissues. Environ. Mol. Mutagen. 56:629–636, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Steven R. Passmore Michael G. Johnson Saleh M. Aloraini Stephan Cooper Mina Aziz Cheryl M. Glazebrook 《Journal of manipulative and physiological therapeutics》2019,42(1):23-33
ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial.MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained.ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed.ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance. 相似文献
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Mei L. Tan Peng Shao Anna M. Friedhuber Mallory van Moorst Mina Elahy Sivanjah Indumathy Dave E. Dunstan Yongzhong Wei Crispin R. Dass 《Biomaterials》2014
Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management. 相似文献
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Robert C. Schutt John Bibawy Mina Elnemr Amy L. Lehnert David Putney Anusha S. Thomas Colin M. Barker Craig M. Pratt 《Methodist DeBakey Cardiovascular Journal》2014,10(3):193-197
The identification of ST-segment elevation on the electrocardiogram is an integral part of decision making in patients who present with suspected ischemia. Unfortunately, ST-segment elevation is nonspecific and may be caused by noncardiac causes such as electrolyte abnormalities. We present a case of ST-segment elevation secondary to hypercalcemia in a patient with metastatic cancer. 相似文献