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991.
992.
Goto M Kawakami N Azegami H Matsuyama Y Takeuchi K Sasaoka R 《Spine》2003,28(4):364-70; discussion 371
993.
Yano H Konagai N Maeda M Itoh M Kuwabara A Kudou T Ishimaru S 《Journal of vascular surgery》2003,37(5):1098-1102
Genitourinary anomalies can present a formidable challenge to the vascular surgeon at abdominal aortic reconstruction. We saw a case of crossed renal ectopia without fusion, a rare anomaly, associated with abdominal aortic aneurysm. Because of risk for injury to the kidney during surgery, preoperative evaluation of this anomaly must include computed tomography, angiography, and intravenous pyelography. Preoperative placement of a ureteral catheter may prevent injury to the anomalous ureter. Renal failure of the ectopic kidney during aortic reconstruction can be a serious problem. We used in situ hypothermic perfusion with cold (4 degrees C) Ringer solution for renal protection, and reimplanted the aberrant renal artery. The postoperative course was good, without major complications. The procedure for renal preservation must be selected on the basis of anatomic findings. We review the literature and present the first case of crossed renal ectopia. 相似文献
994.
Tanaka S Akaike T Wu J Fang J Sawa T Ogawa M Beppu T Maeda H 《Journal of drug targeting》2003,11(1):45-52
Improved delivery of macromolecular drugs to solid tumor is known as the enhanced permeability and retention (EPR) effect of macromolecular drugs and lipids. We report here that a prostaglandin I2 (PGI2) analogue induces enhancement of tumor-selective drug delivery, while it decreases tumor blood flow, in a rat tumor model (AH136B). Beraprost sodium (BPS) is an analogue of PGI2 that is more stable than parental PGI2 in vivo (t1/2 for BPS is > 1 h vs. a few seconds for PGI2). Thus, BPS was administered to tumor-bearing rats to examine its effect on tumor vascular permeability as well as tumor blood flow. The amount of extravasation of the Evans blue-albumin complex in tumor tissue increased from two to three times, whereas tumor blood flow decreased almost 70%, in the group treated with BPS at 7 (microg/kg compared with controls. Tissue blood flow of normal organs such as the kidney and the liver did not change to a significant extent. These findings establish a new role for BPS, not only in enhancing macromolecular drug delivery, but also in reducing the blood supply to tumor tissues. 相似文献
995.
PURPOSE: To present a case of occult macular dystrophy accompanying normal-tension glaucoma. DESIGN: Observational case report. METHODS: Visual function and ophthalmoscopic and electroretinographic findings in a 56-year-old man suffering from gradually progressive photophobia and visual dysfunction were followed up over 4 years. RESULTS: Best-corrected visual acuity was below 20/200, and intraocular pressures remained in the low teens in both eyes. A wedge-shaped visual field defect in the right eye, corresponding to the enlarged disk cupping, and a relative central scotoma in the left were detected. Ophthalmoscopy and fluorescein angiography detected no apparent abnormality at the macular region in either eye. Severely attenuated multifocal electroretinographic responses were recorded from only the central areas, with normal full-field responses. CONCLUSION: Clinicians must look for additional pathologic conditions in patients with normal-tension glaucoma who have unexplained central visual dysfunction. 相似文献
996.
Hayashi H Maeda N Ikeda Y Nishida K Watanabe H Tano Y 《American journal of ophthalmology》2003,135(4):559-561
PURPOSE: To report on a simple method to obtain a better view of corneal opacities during excimer laser phototherapeutic keratectomy (PTK). DESIGN: An interventional case report. METHODS: Phototherapeutic keratectomy was performed under sclerotic scattering illumination with a vitrectomy-endoilluminator at the limbus. RESULTS: During conventional PTK with diffuse illumination, the intraoperative observations of corneal opacities are not as good as that with a slit lamp. Conversely, subtle corneal opacities can be easily seen with sclerotic scattering illumination even under a surgical microscope. CONCLUSIONS: The use of sclerotic scattering illumination during PTK is valuable, because it provides a better view of opacified tissues and avoids excessive ablation. 相似文献
997.
Diagnosing dry eye using a blue-free barrier filter 总被引:5,自引:0,他引:5
Koh S Watanabe H Hosohata J Hori Y Hibino S Nishida K Maeda N Tano Y 《American journal of ophthalmology》2003,136(3):513-519
PURPOSE: To investigate the benefit of the blue-free barrier filter (BF filter) in diagnosing dry eye. DESIGN: Nonrandomized clinical comparison. METHODS: Fifty-three eyes with Sj?gren syndrome (n = 42) or keratoconjunctivitis sicca (n = 11) were enrolled. Fluorescein staining was performed in temporal and nasal conjunctiva, and staining was scored with (BF score) and without the filter (FL score) from 0 to 3. Rose bengal staining was also scored (RB score) similarly. RESULTS: With FL scores of 0, 1, or 2, the BF score was significantly higher: 0.85 +/- 0.37 (P =.031), 1.74 +/- 0.65 (P =.001), and 2.65 +/- 0.48 (P =.001), respectively; with a FL score of 3, the BF score was 3 at all sites. The BF score was superior to the FL score in 66.6% of cases when the FL score was 0 and 1 and in 65.2% when the FL score was 2, but not when the FL score was 3. When the RB score was 0, 1, or 2, the BF score was higher: 1.88 +/- 0.92, 1.78 +/- 0.79, and 2.57 +/- 0.50, respectively (P =.001 for all); when the RB score was 3, the BF score was 2.97 +/- 0.16. The BF score was superior to the RB score in 75.5% of cases when the RB score was 0 and 1 and in 57.8% when the FL score was 2, but not in cases with a RB score of 3. CONCLUSIONS: The BF filter detects damaged conjunctival epithelium stained with fluorescein. Using the filter was beneficial in mild-to-moderate cases, not in severe cases. The BF filter allows diagnosis of dry eye even at the initial stage that is undetectable by conventional observation. 相似文献
998.
Myopic choroidal neovascularization: a 10-year follow-up 总被引:14,自引:0,他引:14
Yoshida T Ohno-Matsui K Yasuzumi K Kojima A Shimada N Futagami S Tokoro T Mochizuki M 《Ophthalmology》2003,110(7):1297-1305
PURPOSE: To clarify the long-term visual outcome of choroidal neovascularization (CNV) in eyes with high myopia in Asian patients. DESIGN: We reviewed the medical records of 25 consecutive patients (27 eyes) with myopic CNV who were followed up for at least 10 years after the onset of CNV. Visual acuity was examined 10 years after CNV onset. INTERVENTION: Demographic and clinical data were obtained from the patients' medical records. MAIN OUTCOME MEASURES: Visual acuity readings during the 10 years after CNV onset. RESULTS: At the onset of CNV, 19 eyes (70.4%) had a visual acuity better than 20/200, and six eyes (22.2%) had a visual acuity better than 20/40. Three years after the onset of CNV, 15 eyes (55.5%) retained a visual acuity of better than 20/200. At 5 and 10 years after the onset, however, visual acuity dropped to 20/200 or less in 24 eyes (88.9%) and in 26 eyes (96.3%), respectively. The logarithm of the minimum angle of resolution (logMAR) visual acuity was significantly worse at 5 and 10 years after onset as compared with that at CNV onset. Chorioretinal atrophy developed around the regressed CNV in 26 eyes (96.3%) at 5 and 10 years after the onset of CNV. CONCLUSIONS: Long-term visual outcome of myopic CNV is extremely poor. The visual acuity of almost all of the patients dropped to 20/200 or less within 5 to 10 years after the onset of CNV, secondary to the development of chorioretinal atrophy around the regressed CNV. These findings indicate that active treatments should be recommended to prevent long-term visual impairment in Asian patients with myopic CNV. 相似文献
999.
The purpose of this study was to evaluate the corneal irregular astigmatism following photorefractive keratectomy (PRK) for myopia. The corneal topography of 30 eyes of 26 patients was measured with the TMS-1 videokeratoscope before and 1 month after PRK. Axial dioptric data were decomposed into four components; A0 (Sphericity), C1 x 2 (Asymmetry), C2 x 2 (Regular astigmatism), and C3 (higher-order irregularity) for the central 3 and 6 mm zone by Fourier series harmonic analysis. Post-operative topographies were divided into those with an irregular and those with a homogeneous pattern, and the Fourier components were compared. In the 6 mm zone, A0 was significantly decreased (P < 0.001), and C1 x 2, C2 x 2, and C3 were significantly increased (P = 0.001, 0.005, 0.002, respectively). In the 3 mm zone, A0 decreased (P < 0.001) and C1 x 2 increased (P < 0.001) significantly. C1 x 2 was correlated with the post-operative corrected visual acuity (P < 0.001, r = 0.647). The irregular pattern group had a larger C1 x 2 component (P < 0.001). The treatment displacement was not correlated with any component. In conclusion, irregular topography due to intraoperative drift or asymmetrical wound healing may play a more important role in the post-operative corneal optical property than mild treatment displacement. 相似文献
1000.
Phototransduction in vertebrate photoreceptor cells mediated by rhodopsin is one of the most comprehensively examined G protein-coupled receptor (GPCR) signaling pathways. The signal transduction pathway can be mapped from the initial absorption of light to conformational changes within rhodopsin, through activation of the G protein transducin, and to the ultimate closure of the cation cGMP-gated channels in the plasma membrane. Furthermore, phototransduction has become an intensely studied model system for understanding the desensitizing processes that allow reduced non-linear responses of photoreceptor cells to increasing levels of illumination. Although some general themes appear to occur in GPCR systems, the details of these desensitizing processes are likely to be specific to each of the receptors. These differences are attributed to the fact that each receptor has unique kinetic constraints, amplification levels, tolerance to basal constitutive activity, intracellular internalization and recycling, redundancy of isoforms, and morphologies of the cell of their expression. One of the biochemical processes that are believed to be a common part of this desensitization of the GPCR-mediated cascade is receptor phosphorylation catalyzed by members of a small family of the GPCR kinases. The enzymatic, physiological and genetic aspects of rhodopsin phosphorylation and rhodopsin kinase have been characterized extensively over the last 30 yr. However, new structurally based approaches to examining rhodopsin kinase and rhodopsin phosphorylation are still awaiting further investigations. We present here a summary of the current understanding of rhodopsin phosphorylation and the properties of rhodopsin kinase, along with some expectations of future investigations into these topics. 相似文献