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排序方式: 共有4626条查询结果,搜索用时 15 毫秒
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Mahmoud Omer Hessein Ali Nina Orlovskaya Amelia Ballesteros Vee San Cheong Kari Martyniak Fei Wei Boyce E. Collins Sergey N. Yarmolenko Jackson Asiatico Michael Kinzel Christopher Ngo Jagannathan Sankar Ashley Calder Timothy Gilbertson Teerin Meckmongkol Ranajay Ghosh Melanie Coathup 《Nutrients》2022,14(15)
The influence of diet on the development of osteoporosis is significant and not fully understood. This study investigated the effect of diets of varying lipid profiles and ω-3, ω-6 and ω-9 composition on the structural and mechanical properties of bone. The hypothesis studied was that a diet high in saturated fat would induce osteoporosis and produce an overall increased detrimental bony response when compared with a diet high in unsaturated ω-6, or ω-9. Male C57BL/6J mice were fed either a control diet, 50:50 mix (saturated:unsaturated) high in ω-9 (HFD50:50), a diet high in saturated fat (HSF) or a polyunsaturated fat diet high in ω-6 (PUFA) over an 8-week duration. Tibiae were retrieved and evaluated using DMA, 3-point-bending, histomorphometry, and microCT. Mice fed a HSF diet displayed key features characteristic of osteoporosis. The loss tangent was significantly increased in the HFD50:50 diet group compared with control (p = 0.016) and PUFA-fed animals (p = 0.049). HFD50:50-fed mice presented with an increased viscous component, longer tibiae, increased loss modulus (p = 0.009), and ultimate stress, smaller microcracks (p < 0.001), and increased trabecular width (p = 0.002) compared with control animals. A diet high in ω-9 resulted in an overall superior bone response and further analysis of its role in bone health is warranted. 相似文献
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Ferhat Eyyupkoca Nilnur Eyerci Mehmet Sait Altintas Mehmet Ali Felekoglu Halil Ibrahim Biter Siho Hidayet Serkan Sivri Bekir Demirtas Omer Faruk Ates 《Arquivos brasileiros de cardiologia》2022,119(6):946
Background:Matrix metalloproteinases (MMPs) can affect myocardial extracellular volume (ECV) and its compartments, and this can provide more detailed information about the mechanism of adverse left ventricular (LV) remodeling (AR) after acute myocardial infarction (MI).Objectives:To investigate the role of changes (Δ) in ECV compartments (matrix volume (MVi) and cell volume (CVi)) in the development of AR after MI, and their relationship with MMP-2 expressions.Methods:Ninety-two first MI patients who underwent 3 Tesla cardiovascular magnetic resonance imaging performed 2 weeks (baseline) and 6 months post-MI. We measured T1 mapping with MOLLI sequences. ECV was performed post-gadolinium enhancement. ECV and LV mass were used to calculate MVi and CVi. AR was defined as an increase of ≥ 12% in LV end-diastolic volume in 6 months. MMPs were measured using a bead-based multiplex immunoassay system at first day (baseline) and 2 weeks post-MI. P <0.05 was accepted as statistically significant.Results:Mean ECV and mean MVi baseline levels were higher in AR group compared to without AR group (42.9±6.4 vs 39.3±8.2%, p= 0.037; 65.2±13.7 vs 56.7±14.7 mL/m2, p=0.010; respectively). CVi levels was similar between groups. A positive correlation was found between baseline levels of MMP-2 and baseline levels of ECV (r=0.535, p<0.001) and MVi (r=0.549, p<0.001). Increased ΔMVi levels was independently predictor of AR (OR=1.03, p=0.010). ΔMVi had superior diagnostic performance compared to ΔECV in predicting AR (ΔAUC: 0.215±0.07, p<0.001).Conclusion:High MVi levels are associated with AR, and ΔMVi was independently predictor of AR. This may be associated with MMP-2 release due to increased inflammatory response. 相似文献
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ObjectiveKörner's septum is a dense bony lamina dividing the mastoid cavity into superficial squamous and deeper petrosal portions at the level of antrum. In this study, we aimed at investigating the association of the Körner's septum with the length of the Cog process and the volume of anterior epitympanic recess (AER), using the 3-dimensional reconstruction models based on high resolution computed tomography sections of the temporal bone.MethodsUsing OsiriX software for MacOS (version 3.8.1, Pixmeo), we measured the volumes from three- dimensional models of anterior epitympanic recess. Anterior epitympanic recess volumes and Cog process lengths of the temporal bones with and without Körner's septum were compared.ResultsCog process length was significantly higher, and AER volume was significantly lower in patients with Körner's septum compared to the patients without. (p < 0.001). Additionally, Cog process length was significantly (p = 0.008), negatively, but weakly (rho= ?0.24) correlated with AER volume.ConclusionTemporal bones with Körner's septum had a longer Cog process and a smaller AER. 相似文献
35.
John Taylor Barnard Omer Onur Cakir David Ralph Faysal A Yafi 《The journal of sexual medicine》2021,18(7):1158-1166
BackgroundDuring the last century, surgical management of erectile dysfunction has evolved from an experimental concept to a core treatment modality with widespread use among the men's health community. Over time, innovations in materials, mechanical design elements, device coatings, and surgical technique have provided patients with low-risk, reliable, and reproducible erectile function with high satisfaction rates.AimTo provide a foundation for future innovation by improving understanding of historical penile prosthetics and the rationale behind incremental technological improvements for the contemporary Men's Health physician.MethodsLiterature review was conducted to generate a comprehensive review of historical technological innovations in penile implant surgery. Companies with FDA approved penile prosthetics in use in the United States were contacted for information regarding technological innovations in the past and future devices in development. A separate literature review was performed to identify any significant future device design elements being tested, even in the ex vivo setting, which may have future clinical applications.OutcomesTechnological innovations in penile implant surgery were described.ResultsCurrent options for the prosthetic surgeon include malleable penile prostheses (MPP), self-contained (2-piece) inflatable penile prostheses, and multicomponent (3-piece) inflatable penile prostheses. Current MPPs consist of a synthetic coated solid core which allow for manipulation of the penis for concealability while maintaining sufficient axial rigidity to achieve penetration when desired. Multi-component (3-Piece) IPPs currently include the Coloplast Titan and Boston Scientific/AMS 700 which consist of a fluid reservoir, intrascrotal pump, and intracavernosal cylinders. The devices have undergone numerous design updates to the cylinders, pump, reservoir, tubing, and external coatings to increase reliability and decrease short- and long-term complications.Clinical ImplicationsFuture innovations in penile prosthetic surgery seek to broaden the indications and applicability to the transgender community and improve both safety and functionality for patient and partner.Strengths & LimitationsThe review is limited primarily to penile prosthetics approved for current or historical clinical use in the United States and may not be representative of the global prosthetic environment. Additionally, the research and development of future innovations, particularly those provided by device manufacturers, is likely limited by non-disclosure to maintain a competitive advantage.ConclusionsPenile prosthetic surgery will undoubtedly remain integral to the treatment of erectile dysfunction, and education regarding the current state of technological innovation will empower the prosthetic surgeon and biomedical engineering community to improve contemporary patient care and drive the development of the next generation of implantable penile prosthetics.Barnard JT, Cakir OO, Ralph D, et al. Technological Advances in Penile Implant Surgery. J Sex Med 2021;18:1158–1166. 相似文献
36.
Qianqian Fan Omer Cavus Lize Xiong Yun Xia 《Journal of acupuncture and meridian studies》2018,11(4):124-132
Spinal cord injury (SCI) is one of the most common causes of death and disability worldwide, and it can result in both permanent disability and serial complications in patients. Research shows that patients with SCI complications are often interested in acupuncture for symptomatic relief. Therefore, the issue of physicians advising their patients regarding the use of acupuncture to alleviate SCI complications becomes pertinent. We review and summarize two types of relevant publications: (1) literature concerning acupuncture for SCI and its complications and (2) underlying mechanisms of acupuncture therapy for SCI. Clinical trials and reviews have suggested that acupuncture effectively manages a range of post-SCI complications, including motor and sensory dysfunction, pain, neurogenic bowel and bladder, pressure ulcers, spasticity, and osteoporosis. The effect of acupuncture on post-SCI orthostatic hypotension and sexual dysfunction remains unclear. Decreased oxidative stress, inhibition of inflammation and neuronal apoptosis, regulation of the expression and activity of endogenous biological mediators, and increased regenerative stem cell production are the possible mechanisms of acupuncture therapy for SCI. Although many limitations have been reported in previous studies, given the evidence for the efficacy of acupuncture, we recommend that physicians should support the use of acupuncture therapy for SCI complications. 相似文献
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Mohamed A. Omer M.D. Steven B. Laster M.D. Amit Amin M.D. Michael L. Main M.D. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(7):1092-1094
A 61‐year‐old man presented with unstable angina 16 years after undergoing coronary artery bypass grafting with a left internal mammary artery graft to the left anterior descending coronary artery and a sequential saphenous vein graft (SVG) to the right coronary artery and an obtuse marginal branch. Transthoracic echocardiography (TTE) with a Philips iE33 machine and an S5 transducer revealed a 5.3 cm × 4.6 cm mass with a central echolucent area, surrounded by a peripheral zone of increased echodensity adjacent to, and partially compressing, the right atrium. Contrast echocardiography following an intravenous bolus injection of Definity revealed late appearance of contrast within the mass consistent with a giant SVG aneurysm. Coronary artery bypass graft angiography revealed a giant aneurysm in the SVG proximal to the RCA anastomosis; the distal limb of the graft to the obtuse marginal branch was occluded. Under intravascular ultrasound guidance, a 7‐mm spider filter was placed in the distal graft; then, a 6 mm × 10 cm Viabahn self‐expanding nitinol polyethylene terephthalate‐covered stent was deployed in the SVG with good seal zones proximally and distally. A follow‐up contrast‐enhanced transthoracic echocardiogram 1 day postprocedure revealed partial thrombosis of the aneurysm cavity. Ultrasound contrast did not appear in the aneurysm following intravenous injection, consistent with complete exclusion from the systemic circulation. This is the first report demonstrating feasibility of contrast‐enhanced transthoracic echocardiography for the diagnosis of SVG aneurysm and confirming procedural success by documenting exclusion from the systemic circulation following intervention. 相似文献
40.
Tansu Degirmenci Bulent Gunlusoy Zafer Kozacioglu Murat Arslan Omer Koras Burak Arslan Suleyman Minareci 《The Kaohsiung journal of medical sciences》2014,30(3):153-158
The aim was to compare pneumatic and holmium:yttrium-aluminum-garnet laser in the treatment of impacted ureteral stones with different locations and to identify the risk factors for complications. Between March 2005 and November 2012, a total of 230 patients underwent ureteroscopic lithotripsy for impacted stones. Of the patients, 117 had pneumatic and 113 had laser lithotripsy for the fragmentation of the stones. Treatment outcomes based on evidence of being stone free were evaluated. Preoperative, operative, and postoperative follow-up findings were analyzed and compared. There was a difference between the two groups according to overall stone clearance rate (93.8% vs. 80.3%, p = 0.002). There was no statistically significant difference for distal location between the laser and pneumatic groups (96.8% vs. 91.7%, p = 0.288). For 10 patients with intrarenally migrated stones who were managed with flexible ureterorenoscopy in the same session, laser lithotripsy was more successful than pneumatic for proximal ureteral stone (94.4% vs. 67.9%, p = 0.007). The overall complication rate was 26.1%. There was no statistically significant difference between the two groups (29% vs. 23%, p = 0.296). Multivariate logistic regression analysis revealed that the proximal location was a statistically significant parameter for the occurrence of complications in both groups (p = 0.001 for PL, p = 0.004 for laser). The pneumatic and holmium:yttrium-aluminum-garnet laser lithotripsy are effective in the treatment of distal impacted stones. Both treatments with semirigid ureteroscopy are acceptable for proximal impacted ureteral stones, but holmium laser lithotripsy has an advantage of use with flexible ureteroscope for intrarenally migrated stone. 相似文献