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991.
Messias A Ramos Filho JA Messias K Almeida FP Costa RA Scott IU Gekeler F Jorge R 《Documenta ophthalmologica. Advances in ophthalmology》2012,124(3):225-236
To evaluate changes in electroretinographic (ERG) findings after panretinal photocoagulation (PRP) compared to PRP plus intravitreal
injection of ranibizumab (IVR) in eyes with high-risk proliferative diabetic retinopathy (PDR). Patients with high-risk PDR
and no prior laser treatment were assigned randomly to receive PRP (PRP group; n = 9) or PRP plus IVR (PRPplus group; n = 11). PRP was administered in two sessions (weeks 0 and 2), and IVR was administered at the end of the first laser session
(week 0) in the PRPplus group. Standardized ophthalmic evaluations including (ETDRS) best-corrected visual acuity (BCVA), and fluorescein angiography
to measure area of fluorescein leakage (FLA), were performed at baseline and at weeks 16 (±2), 32 (±2) and 48 (±2). ERG was
measured according to ISCEV standards at baseline and at week 48 (±2). At 48 weeks, 2,400–3,000 laser spots had been placed
in eyes in the PRP group, while only 1,400–1,800 spots had been placed in the PRPplus group. Compared to baseline, there was a statistically significant (P < 0.05) FLA reduction observed at all study visits in both groups, with the reduction observed in the PRPplus group significantly larger than that in the PRP group at week 48. ROD b-wave amplitude was significantly reduced to 46 ± 5 %
(P < 0.05) of baseline in the PRP group and 64 ± 6 % (P < 0.05) in the PRPplus group. This reduction was significantly larger in the PRP group than in the PRPplus group (P = 0.024; t Test). Similar results were observed for the dark-adapted Combined Response (CR) b-wave amplitude, with a reduction at 48 weeks
compared to baseline of 45 ± 4 % in the PRP group and 62 ± 5 % in the PRPplus group; the reduction in CR b-wave amplitude was significantly larger in the PRP group than in the PRPplus group (P = 0.0094). CR a-wave, oscillatory potentials, cone single flash, and 30 Hz flicker responses showed statistically significant
within-group reductions, but no differences in between-group analyses. These results suggest that treating high-risk PDR with
PRP plus IVR is effective for PDR control, and permits the use of less extensive PRP which, in turn, induces less retinal
functional loss, in particular for rod-driven post-receptoral responses, than treatment with PRP alone. 相似文献
992.
FR Zanetti EA Fulco FR Chaves AP da Costa Pinto CE Arieta RP Lira 《Indian journal of ophthalmology》2012,60(4):277-281
Purpose:
To compare the effects of preoperative use of topical anti-inflammatory prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery.Design:
Randomized clinical trial.Materials and Methods:
This single-center, masked, randomized clinical study comprised 140 patients scheduled for cataract surgery. Patients (35 in each group) were randomized to receive placebo, prednisolone acetate, ketorolac tromethamine 0.4% or nepafenac. These eye drops were administered three times daily for the two days prior to surgery. The pupillary diameters were measured by the surgeon using a compass prior to the corneal section and at the end of surgery. The primary outcome was the number of patients with pupil ≥ 6mm at the end of the surgery; the secondary outcome was the number of patients with pupil ≥ 6mm at the beginning of the surgery.Results:
All the patients achieved pupil ≥ 6mm at the beginning of the surgery. The number of patients in the prednisolone (29/35), nepafenac (31/35) and ketorolac (30/35) groups with pupil ≥ 6mm was greater than in the placebo group in the maintenance of intraoperative mydriasis (19/35 – P =0.003). There was no statistical difference among the prednisolone, nepafenac and ketorolac groups in the maintenance of intraoperative mydriasis (P =.791). There were no complications during surgery or related to the preoperative use of the eye drops.Conclusion:
Preoperative use of ketorolac, prednisolone and nepafenac was effective in maintaining intraoperative mydriasis when compared with placebo. 相似文献993.
Fernandez-Gonzalo Rodrigo Nissemark Catarina Åslund Birgitta Tesch Per A Sojka Peter 《Journal of neuroengineering and rehabilitation》2014,11(1):1-10
Myoelectric control has been used for decades to control powered upper limb prostheses. Conventional, amplitude-based control has been employed to control a single prosthesis degree of freedom (DOF) such as closing and opening of the hand. Within the last decade, new and advanced arm and hand prostheses have been constructed that are capable of actuating numerous DOFs. Pattern recognition control has been proposed to control a greater number of DOFs than conventional control, but has traditionally been limited to sequentially controlling DOFs one at a time. However, able-bodied individuals use multiple DOFs simultaneously, and it may be beneficial to provide amputees the ability to perform simultaneous movements. In this study, four amputees who had undergone targeted motor reinnervation (TMR) surgery with previous training using myoelectric prostheses were configured to use three control strategies: 1) conventional amplitude-based myoelectric control, 2) sequential (one-DOF) pattern recognition control, 3) simultaneous pattern recognition control. Simultaneous pattern recognition was enabled by having amputees train each simultaneous movement as a separate motion class. For tasks that required control over just one DOF, sequential pattern recognition based control performed the best with the lowest average completion times, completion rates and length error. For tasks that required control over 2 DOFs, the simultaneous pattern recognition controller performed the best with the lowest average completion times, completion rates and length error compared to the other control strategies. In the two strategies in which users could employ simultaneous movements (conventional and simultaneous pattern recognition), amputees chose to use simultaneous movements 78% of the time with simultaneous pattern recognition and 64% of the time with conventional control for tasks that required two DOF motions to reach the target. These results suggest that when amputees are given the ability to control multiple DOFs simultaneously, they choose to perform tasks that utilize multiple DOFs with simultaneous movements. Additionally, they were able to perform these tasks with higher performance (faster speed, lower length error and higher completion rates) without losing substantial performance in 1 DOF tasks. 相似文献
994.
Joey M. Jabbour Bilal H. Malik Cory Olsovsky Rodrigo Cuenca Shuna Cheng Javier A. Jo Yi-Shing Lisa Cheng John M. Wright Kristen C. Maitland 《Biomedical optics express》2014,5(2):645-652
This paper presents the use and characterization of an electrically focus tunable lens to perform axial scanning in a confocal microscope. Lateral and axial resolution are characterized over a >250 µm axial scan range. Confocal microscopy using optical axial scanning is demonstrated in epithelial tissue and compared to traditional stage scanning. By enabling rapid axial scanning, minimizing motion artifacts, and reducing mechanical complexity, this technique has potential to enhance in vivo three-dimensional imaging in confocal endomicroscopy.OCIS codes: (170.0110) Imaging systems, (170.1790) Confocal microscopy, (170.3880) Medical and biological imaging, (170.3890) Medical optics instrumentation, (170.6900) Three-dimensional microscopy 相似文献
995.
996.
997.
Rodrigo Polaquini Simões Viviane Castello‐Simões Renata Gonçalves Mendes Bruno Archiza Daniel Augusto dos Santos José Carlos Bonjorno Jr Claudio Ricardo de Oliveira Aparecida Maria Catai Ross Arena Audrey Borghi‐Silva 《Clinical physiology and functional imaging》2014,34(2):98-108
The purposes of this study were to determine anaerobic threshold (AT) during discontinuous dynamic and resistive exercise protocols by analysing of heart rate variability (HRV) and blood lactate (BL) in healthy elderly subjects and compare the cardiovascular, metabolic and autonomic variables obtained from these two forms of exercise. Fourteen elderly (70 ± 4 years) apparently healthy males underwent the following tests: (i) incremental ramp test on cycle ergometer, (ii) one repetition maximum (1RM) leg press at 45°, (iii) a discontinuous exercise test on a cycle ergometer (DET‐C) protocol and (iv) a resistance exercise leg press (DET‐L) protocol. Heart rate, blood pressure and BL were obtained during each increment of exercise intensity. No significant differences (P>0·05) were found between methods of AT determination (BL and HRV) nor the relative intensity corresponding to AT (30% of maximum intensity) between the types of exercise (DET‐C and DET‐L). Furthermore, no significant differences (P>0·05) were found between the DET‐C and DET‐L in relation to HRV, however, the DET‐L provided higher values of systolic blood pressure and BL (P<0·05) from the intensity corresponding to AT. We conclude that HRV was effective in determination of AT, and the parasympathetic modulation responses obtained during dynamic and resistive exercise protocols were similar when compared at the same relative intensity. However, DET‐L resulted in higher values of blood pressure and BL at workloads beyond AT. 相似文献
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1000.
Nuevo JA Vilacosta I Parra A Jiménez P Rodrigo JL Puche JJ 《Revista espa?ola de cardiología》2001,54(4):529-531
Ventricular diverticulum are small outpouchings, in the cardiac wall, which are mostly described as a part of malformation syndromes. This finding is infrequent in asymptomatic patients with no pathology in the thoraco abdominal line. The case we present shows a diverticulum in the cardiac apex in a male patient with no cardiological clinic manifestations and with an abnormal electrocardiogram. At present, magnetic resonance is the best diagnostic test, for this kind of malformation, and is also the most reliable in the follow-up of these patients. 相似文献