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51.
Ocular toxicity of intravitreal clarithromycin.   总被引:5,自引:0,他引:5  
OBJECTIVE: To investigate the ocular toxicity and clearance of intravitreal clarithromycin lactobionate (Klaricid) and to determine the highest nontoxic dose. MATERIALS AND METHODS: To evaluate toxicity, 24 New Zealand white rabbits were divided into six groups (four rabbits each). Rabbits were examined preoperatively and electroretinography (ERG) was performed. The left eyes of the animals served as controls and received intravitreal injection of 0.1 mL sterile water. Klaricid (0.1 mL) was injected into the midvitreous cavity of the right eyes at concentrations of 25 microg, 250 microg, 500 microg, 1.0 mg, 2.0 mg, and 4.0 mg/0.1 mL. The animals were followed up to 15 days postinjection by clinical examination and ERG. The animals were killed and the eyes were enucleated and processed for light microscopy. Ten New Zealand rabbits were used for the vitreous clearance study as drug test rabbits and two additional rabbits were used to generate control retina and vitreous. The highest nontoxic dose (1 mg) was injected into the vitreous and the concentration of clarithromycin in the vitreous was determined using high-performance liquid chromatography at various time intervals after injection. RESULTS: Cataract occurred after intravitreal doses of 2.0 and 4.0 mg. Electroretinography showed decreasing b-wave amplitude with both dark- and light-adapted stimulus in the 4.0-mg group; it was normal in other groups. Histopathologic sections showed localized retinal necrosis and disorganization with the 2.0 and 4.0 mg dosage. No histologic changes were found in the other groups. The half-life of intravitreal clarithromycin was found to be 2 hours. No metabolites of clarithromycin were observed in the vitreous samples. CONCLUSION: Intravitreal clarithromycin lactobionate is nontoxic to rabbit eyes up to a dose of 1.0 mg. Because of its broad-spectrum antibiotic effect and appropriate half-life in the vitreous, it may be a good choice for intravitreal treatment of susceptible organisms.  相似文献   
52.
PURPOSE: To evaluate the effectiveness of laser-assisted subepithelial keratectomy (LASEK) to treat residual refractive errors after laser in situ keratomileusis (LASIK). SETTINGS: Isik Eye Clinic, Ankara, Turkey. METHODS: This retrospective study included 24 eyes of 15 patients who had retreatment by LASEK for residual refractive errors after myopic LASIK. All patients had examinations that included slitlamp biomicroscopy, subjective and cycloplegic refractions, uncorrected visual acuity (UCVA), best corrected visual acuity, corneal topography, and pachymetry preoperatively and postoperatively. Postoperative examinations were performed at 1 week and 1, 3, and 6 months. RESULTS: The patient cohort comprised 9 men and 6 women. The median spherical equivalent (SE) of attempted correction for retreatment with LASEK was -1.25 diopters (D). The median follow-up after LASEK was 11.5 months (range 6 to 16 months). At the end of the follow-up, the median SE of the refractive error was -0.38 D. The median UCVA increased from 20/45 before LASEK to 20/25 at the last follow-up visit, which was statistically significant (P<.001). After LASEK, significant postoperative haze developed in 5 eyes. In all 5 eyes, the estimated ablation depth was more than 40 mum and the SE of attempted correction was -2.00 D or greater. CONCLUSIONS: Laser-assisted subepithelial keratectomy retreatment in eyes with myopic regression after LASIK resulted in a significant improvement in UCVA that was comparable to the improvement after flap lifting. An SE of attempted correction greater than -2.00 D was associated with a significant rate of haze.  相似文献   
53.
ObjectiveThe aim of this study was to determine the epidemiologic characteristics of, and the treatments used for, recurrent herpes labialis (RHL) in health students.MethodsA cross-sectional study was conducted with the participation of 333 nursing and midwifery students. Data on the sociodemographic characteristics of the participants, their history of RHL, and the treatments were collected by means of a standard self-reported questionnaire form.ResultsThe point prevalence of RHL was 3.9%, the annual prevalence was 44.7%, and the lifetime prevalence was 52.5%. These prevalences were not related to the participants' place of residence, level of income, school, gender, marital status, or smoking status (p > 0.05). RHL was frequently seen on the right side of the lower lip (17.9%). One third of the students who experienced RHL stated that they had applied treatment to the lesion. However, only 20.1% stated that they had used antiviral therapy. Treatment was recommended by a physician for only 16.1% of the subjects.ConclusionsThe prevalence of RHL was high among the health students, who were considered to represent young adults. Although they were students in a school of health, they lacked knowledge about RHL.  相似文献   
54.
PURPOSE: To compare the ocular hypotensive efficacy and safety of topical bimatoprost and timolol-dorzolamide combination in patients with primary open-angle glaucoma (POAG) or ocular hypertension during 6 months of treatment. METHODS: A sample of 65 patients with a diagnosis of POAG or ocular hypertension were randomized to receive either bimatoprost 0.03% once daily or timolol-dorzolamide combination twice daily. Study visits occurred at baseline and after 2 weeks and 1, 3 and 6 months of therapy. Intraocular pressure (IOP) measurements were performed at 12.00 hours at all study visits and also at 08.00 hours and 16.00 hours at baseline and 6-month visits. At each visit, local and systemic side-effects that occurred during the treatment period were recorded. Student's t-test was used to compare the differences between IOP values. RESULTS: Differences in IOP between the bimatoprost and timolol-dorzolamide groups were statistically insignificant at all study visits (p > 0.05). In the bimatoprost-treated group, the IOP reduction was 6.2 +/- 1.8 mmHg, whereas it was 6.5 +/- 2.3 mmHg in the timolol-dorzolamide group after 6 months of treatment. The difference was not statistically significant (p = 0.48). CONCLUSIONS: The IOP-lowering efficacies of bimatoprost and timolol-dorzolamide combination were similar over a 6-month follow-up. Both bimatoprost and the timolol-dorzolamide combination were well tolerated. Bimatoprost can be used as a longterm monotherapy agent in the treatment of POAG and ocular hypertension.  相似文献   
55.
PURPOSE: To evaluate the rate of apoptosis in orbital fibroadipose tissue in Graves' ophthalmopathy (GO) patients and investigate its associations with disease characteristics. METHODS: Orbital tissue samples were obtained during decompression surgery from 25 GO patients. Disease activity was evaluated using the Clinical Activity Score, while the clinical features of GO were evaluated using the Total Eye Score (TES). Tissue samples of 12 patients without any thyroid or autoimmune disease were studied as controls. The rate of apoptosis was evaluated with a terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling (TUNEL) assay, and ultrastructural features of apoptosis were evaluated with electron microscopy. RESULTS: The rate of apoptosis in orbital fibroadipose tissue was significantly higher in GO cases than in the control group (p < 0.001) and significantly correlated with TES (r: 0.545; p = 0.005). The rate of apoptosis was 7.9% +/- 6.5%, and 22.0% +/- 7.8% in type 1 and type 2 cases, respectively (p = 0.001). The rate of apoptosis was 21.6% +/- 7.5% in eyes showing dysthyroid optic neuropathy (DON) and 6.7% +/- 5.4% in eyes without DON (p = 0.005). CONCLUSIONS: The rate of apoptosis was high in the orbital fibroadipose tissue of GO cases and was related to the clinical features of the disease.  相似文献   
56.
OBJECTIVE: To evaluate the correlation between adenoidal-nasopharyngeal ratio (AN ratio) and tympanogram in children. STUDY DESIGN: A prospective clinical study from June 2002 to May 2003. METHOD: A total of 64 children, aged 6-9 years who presented with nasal obstruction, snoring, mouth breathing, and hyponasal speech were examined and AN ratio was calculated by using the lateral neck radiograms and compared with the tympanometric values. The relationship between AN ratio and middle-ear pressure was evaluated, regarding the AN ratio of 0.71. The chi-square test was used to analyze the correlation between AN ratio and middle ear pressures and Wilcoxon test was used to compare the changes between the mean AN ratio values, and mean middle ear pressures (including A and C type tympanograms) before and after medical therapy. RESULTS: Middle-ear effusions and C type tympanograms in impedance audiometry were both related to eustachian tube dysfunction resulting from enlargement of the adenoids with AN ratios higher than 0.71. Middle ear pressures were found lower in children with AN ratio greater than 0.71 than in children AN ratio less than 0.71 and the difference was highly significant (p<0.001). Although medical treatment of large adenoids was rather effective to shrink the adenoid tissue (p<0.001), it did not cause a statistically significant change in tympanometric values (p>0.05). CONCLUSIONS: Antibiotherapy is effective in reducing adenoid size without signs and symptoms of infection. The reduction of the adenoids in size after 3 weeks of antibiotherapy has an positive effect on recovery of eustachian tube function but is not sufficient in patients with middle ear effusion. Early ventilation tube insertion may be an alternative therapy for the middle ear effusions not improving by 3 weeks medical therapy.  相似文献   
57.
OBJECTIVE: To determine whether Henle's spine could be used as a reliable and multipurpose landmark for the other important structures of the skull base. MATERIALS AND METHODS: Ninety-two specimens from 46 cadaveric adult dry skulls were studied. Two imaginary lines and a triangle were defined: a spinopterygoidal line extending from Henle's spine to the root of the medial pterygoid plate, a bispinal line extending from one Henle's spine to the contralateral one, and a parapetrosal triangle lying between the spinopterygoidal line, the bispinal line and the sagittal midline. The parapetrosal triangle encompasses nearly all the main structures of the skull base, including the petrosal internal carotid artery. RESULTS: Along the spinopterygoidal line the distance from Henle's spine to the spine of the sphenoid was found to be about 3 cm, to the foramen spinosum 3.5 cm, to the posterior and anterior margins of the foramen ovale 4 and 4.5 cm, to the root of the lateral pterygoid plate 5 cm, to the root of the medial pterygoid plate 5.5 cm, and to the vomer 6.5-7 cm. Along the bispinal line, the distance from Henle's spine to the stylomastoid foramen was found to be about 1.5 cm, to the lateral and medial margins of the jugular foramen 2.5 and 3.5 cm, to the external orifice of the hypoglossal canal 4 cm, and to the foramen magnum 5 cm. CONCLUSION: Henle's spine with its superficial and central position can be used to localize important anatomical structures during skull-base surgery.  相似文献   
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59.
Prosthetic valve endocarditis caused by Pseudomonas aeruginosa is refractory to medical treatment alone and early valve replacement is necessary. We describe a 40-year-old patient in whom endocarditis developed in the early postoperative period, and reoperation was not considered feasible. Ciprofloxacin was administered orally in order to suppress bacteremia for 36 months. Long-term oral ciprofloxacin may provide an opportunity in the treatment of prosthetic valve endocarditis caused by Ps. aeruginosa in patients who are unfavorable candidates for reoperation.  相似文献   
60.
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