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排序方式: 共有2136条查询结果,搜索用时 15 毫秒
101.
Ozcan R Kayikcioglu Iryna Falkenstein Linguen Cheng Igor Kozak Laurie La Bree Stanley P Azen Flossie Wong-Staal Nicholas F Paoni William R Freeman 《Journal of ocular pharmacology and therapeutics》2006,22(1):1-9
PURPOSE: The aim of this study was to evaluate the efficacy of hammerhead ribozyme to the proliferating cell nuclear antigen (PCNA-Rz) and 5-fluorouracil (5-FU) in experimental choroidal neovascularization (CNV) model in rats. METHODS: Laser was used to induce CNV in each eye of 44 rats. For angiography studies, injections of either a mixture of PCNA-Rz 10 microg/microL and 5-FU 1.5 microg/microL, versus the same dose of either drug alone versus a control injection of Hanks' Balanced Salt Solution (HBSS) were performed. We also studied this regimen to evaluate scar size and volume. RESULTS: There was significantly less angiographic leakage for the treated eyes compared to the controls by 3.53 grading points (P = 0.0005); CNV leakage was reduced in the combination group compared to 5-FU alone by 1.75 grading units (P = 0.04) and compared to PCNARz by 2.22 grading units (P = 0.07). The scar size and volume were smaller (diameter 354.6 +/- 174.2 microm vs 477.3 +/- 157.0 microm), (thickness 52.7 +/- 43.0 microm versus 79.6 +/- 46.2 microm) with a reduction in scar volume of 44.8%. CONCLUSIONS: Subretinal injection of PCNA-Rz and 5-FU mixture is more effective as treatment of laser-induced CNV, than either drug alone. The majority of the antiangiogenic effect is a result of 5-FU activity with a contribution by the PCNA ribozyme. 相似文献
102.
Igor Kozak Ozcan R Kayikcioglu Lingyun Cheng Iryna Falkenstein Gabriel A Silva Diana X Yu William R Freeman 《Journal of ocular pharmacology and therapeutics》2006,22(5):362-369
PURPOSE: The aim of this study was to investigate the extent if recombinant human hyaluronidase (rhuPH20) can enhance trans-scleral penetration of sub-Tenon's dexamethasone (DM) into the posterior segment of the eye. METHODS: rhuPH20 was purified from conditioned media through a series of ion exchange, hydrophobic interaction, aminophenylboronate, and hydroxyapatite chromatography to greater than 90% purity based upon specific activity. Only the right eye of each rabbit was injected. The first group (n = 16) received an injection of DM and rhuPH20, whereas the second group (n = 16) received DM only. The eyes were enucleated 1, 2, 3, and 6 h after the injection, and the choroid, retina, vitreous, aqueous, and serum were harvested. DM concentration was assessed by mass spectrometry. Histology (n = 2) and immunohistochemistry (n = 2) was performed to detect toxicity and the presence of the rHuPH20, respectively. RESULTS: We observed no histopathologic damage to ocular tissues after sub-Tenon's injection. This enzyme significantly increased DM level in the choroid and the retina 3 h after administration. The rise in levels was transient returning to normal levels by 6 h. CONCLUSIONS: Sub-Tenon's coinjection of rHuPH20 with DM resulted in a general increase in DM levels in ocular tissues and the serum, with significant increase in the choroid and the retina, 3 h after administration. 相似文献
103.
D Uygur S Ki? R Tuncer F S Ozcan S Erkaya 《International journal of gynaecology and obstetrics》2002,78(2):127-130
OBJECTIVES: Our goal was to identify risk factors associated with umbilical cord prolapse and to review the perinatal outcome of cases of cord prolapse. METHODS: During the study years 77 cases were identified retrospectively. Associations between cord prolapse and potential risk factors were evaluated by means of the odds ratio. RESULTS: Of the 77 fetuses with umbilical cord prolapse 9.1% had a fetal weight of < 2500 gas compared with 9.4% for fetuses in control group (P > 0.05). The umbilical cord prolapse occurred in association with vertex presentation 66 times (85.7%), breech presentation nine times (11.7%) and transverse presentation two times (2.6%). The occurrence of breech presentation among the control cases was 2.6%, and that of transverse lie was 1.7% (P < 0.01). Case mothers were 1.6 times more likely to be multiparas compared with the control group (P < 0.01). The perinatal mortality rate was 39/1000. CONCLUSIONS: Our study showed that abnormal fetal presentation and multiparity are associated with an increased risk of umbilical cord prolapse. The association of risk of cord prolapse with low birth weight was statistically insignificant (P > 0.05). We suggest that the cesarean delivery decreased the risk of perinatal mortality among cases of cord prolapse. 相似文献
104.
Massive bilateral inferior concha bullosa. 总被引:2,自引:0,他引:2
105.
K. Murat Ozcan Adin Selcuk Vedat Oruk Yasin Sarikaya Huseyin Dere 《European archives of oto-rhino-laryngology》2008,265(2):185-188
Ethmomaxillary sinus is a variation of the posterior ethmoid cells. It is formed by the extension of the posterior ethmoid
cells into the maxillary sinus and drains into superior nasal meatus. It is incidentally seen on paranasal sinus computerized
tomography (CT) scans. Its prevalence has been reported as 0.7 and 2% in two studies. In this study, paranasal CT scans of
466 patients were investigated for the presence of ethmomaxillary sinus. The patients had paranasal CT with the preliminary
diagnoses of septal deviation, chronic inflammatory paranasal sinus disease and nasal turbinate disorders. The ethmomaxillary
sinus was present in nine of those patients (1.93%). It was septated in one of them. The CTs were further investigated for
other anatomical variations and co-existent mucosal disease of the paranasal sinuses. 相似文献
106.
Sarici SU Alpay F Unay B Ozcan O Gökçay E 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(11):1249-1253
The efficacy and usefulness of two types of phototherapy differing in the source, wavelength and irradiance of the light, conventional phototherapy consisting of special blue light and fiberoptic phototherapy, were compared in a relatively larger series of term newborns with non-haemolytic and more significant hyperbilirubinaemia than those in previous studies. In total, 108 newborns were allocated sequentially to receive either conventional phototherapy consisting of five special blue lamps or fiberoptic phototherapy. The average spectral irradiance measured at the skin surface level of newborns during the study period was significantly greater in the conventional phototherapy group. The special blue lamp of the conventional phototherapy unit had an emission spectrum almost identical to the bilirubin absorption spectrum, whereas the tungsten-halogen lamp of the fiberoptic phototherapy had a broad emission through the blue and green wavelengths (mainly in the green spectrum). Phototherapy was more effective in the conventional phototherapy group; the duration of exposure to phototherapy (h) was significantly shorter, and the overall bilirubin decline rate (as micromol/l/h and %/h) was significantly greater in the conventional phototherapy group. According to the nursing personnel, fiberoptic phototherapy was more comfortable than the conventional phototherapy frame because of the easier accessibility and handling of the infants during phototherapy. They complained of giddiness, nausea, glare, temporary blurring of vision and difficulty in detecting the skin colour changes of newborns with the blue light of the conventional phototherapy unit. Conventional phototherapy consisting of special blue fluorescent lamps with approximately twofold higher irradiance and an emission spectrum almost identical to the bilirubin absorption spectrum is preferable to fiberoptic phototherapy in the standard treatment of term newborns with non-haemolytic hyperbilirubinaemia. 相似文献
107.
We describe an unusual case of coronary artery-left ventricular fistulae associated with apical hypertrophic cardiomyopathy in a 63-year-old man who had a 2-year history of angina pectoris without significant coronary atherosclerosis. It is important to recognize this anomaly as it may be the source of angina in patients without angiographic evidence of major atherosclerotic coronary artery disease. 相似文献
108.
A 42-year-old-woman, with a 2 year history of non-Hodgkin's lymphoma suffered sudden bilateral visual loss. This unusual patient presented with an unifocal choroidal tumor in the superionasal quadrant in both eyes. Fluorescein angiography revealed early and late intense subretinal fluorescence. Cytological examination of the anterior chamber and vitreous tap material revealed abnormal lymphocytes compatible with NHL. Diffuse choroidal infiltration was diagnosed and treated with radiotherapy. Radiotherapy did not provide local control and preservation of the vision. Non-Hodgkin's lymphoma can infiltrate to the choroid and radiotherapy may not be efffective in every case. 相似文献
109.
Bakirel T Keleş O Karataş S Ozcan M Türkmen G Candan A 《Aquatic toxicology (Amsterdam, Netherlands)》2005,71(2):175-181
Linear alkylbenzene sulphonate (LAS) is among the most widely disseminated xenobiotics to enter waste streams and the aquatic environment. In the present investigation, we present a novel approach to evaluate in toxicity of LAS. The effects of sublethal levels (0.2 and 0.4 mg/l) of LAS on non-specific immune system, phagocytosis, respiratory burst and lyzosyme activity, and specific growth rate in the rainbow trout, Oncorhynchus mykiss, during a 54-day exposure were examined by a static bioassay test procedure. The phagocytic activity of leukocytes from fish exposed to 0.4 mg/l LAS statistically decreased compared with the control fish values. No significant reductions were observed in the extra-intracellular respiratory burst and lysozyme activities after exposure to LAS at any of the concentrations tested. The final body weight in fish groups exposed to the LAS were found to be significantly lower than in the control. The specific growth rate results also supported the result above. The results of this study showed sublethal doses (0.2-0.4 mg/l) of LAS caused to statistically insignificant suppression of non-specific immune system mechanisms excluding phagocytosis in fish at laboratory conditions. These doses of LAS may produce potential synergism on immune system when presented with other environmental pollutants. 相似文献