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91.
Vassilios?P.?Kozobolis Emmanouil?V.?ChristodoulakisEmail author Irene?I.?Naoumidi Charalambos?S.?Siganos Efstathios?T.?Detorakis loannis?G.?Pallikaris 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(6):478-483
Background Tear secretion and tear film stability seem to be influenced by pseudoexfoliation syndrome (PEX). Histopathological evaluation of conjunctival goblet cells in PEX patients might explain the influence on tear film stability.Methods In a prospective, cross-sectional study, 40 eyes of 40 patients with PEX (study group) had measurement of Schirmer test with anesthesia and break-up time prior to cataract surgery. At the end of an uneventful operation, a 1×1.5 mm sample of conjunctival tissue was obtained and light and electron microscopy were performed. Results were compared with a control group. Histology evaluation was masked. Primary outcome measures included Schirmer test with anesthesia, break-up time, goblet cell density and morphological character of conjunctiva and conjunctival goblet cells.Results Both Schirmer test and break-up time values were significantly lower (P=0.01 and P=0.001) in the PEX patients (mean 10.6 mm and 8.6 s respectively) than in the control group (13.4 mm and 12.3 s respectively). The number of goblet cells in patients with PEX compared with the control group showed no statistically significant difference (P=0.66). Use of trichrome stain revealed significant differences in the staining properties of goblet cells between patients with PEX and controls. On electron microscopy, typical pseudoexfoliation filaments were found in the connective tissue of conjunctiva of PEX patients. Remarkable changes of mucin pockets in the study group were also noticed; they had extremely irregular distribution, various forms of size and appearance and even complete collapse.Conclusion Pseudoexfoliation seems to alter basic features of goblet cell morphology, thus affecting tear film stability. Further studies are necessary to determine the exact mechanism. 相似文献
92.
Anastasiadis PG Kotini A Anninos P Adamopoulos A Sigalas J Koutlaki N 《Prenatal diagnosis》2003,23(5):405-409
OBJECTIVE: We studied how chaotic and periodic heart rate dynamics differ between normal fetuses (n = 19) and intrauterine growth restricted fetuses (n = 11) at 34 to 37 weeks of gestation. We quantified the chaotic dynamics of each heart rate time series obtained by fetal magnetocardiography (FMCG) using correlation dimension. METHODS: The FMCG was recorded digitally by a single-channel biomagnetometer in an electrically shielded room of low magnetic noise. The position of the fetal heart was determined using ultrasonography. RESULTS: The correlation dimension was significantly lower in IUGR than in normal fetuses (p < 0.001, t-test). The periodic dynamics were also obtained by FMCG and measured by power spectrum. The low-frequency components and therefore the periodicity of the low-frequency range were significantly higher in IUGR than in normal fetuses (p < 0.001, t-test). CONCLUSIONS: The analysis of FMCG recordings may offer important perspectives to understand significant features of the heart function of the fetuses. This technique improves the recognition of IUGR fetuses over healthy ones and may help improve perinatal morbidity and mortality. 相似文献
93.
Correlation between biomagnetic and Doppler findings of umbilical artery in fetal growth restriction
Kotini A Avgidou K Koutlaki N Sigalas J Anninos P Anastasiadis P 《Prenatal diagnosis》2003,23(4):325-330
OBJECTIVE: To assess the value of biomagnetic recordings of the umbilical artery over Doppler ultrasound screening in order to predict complications of impaired uteroplacental blood flow in fetuses with intrauterine growth restriction (IUGR). METHODS: Our study population included 11 IUGR preeclamptic (34-37-weeks gestation; birth weight 1969 +/- 129 g) and 19 normal pregnancies (34-37-weeks gestation; birth weight 3195 +/- 229 g). Umbilical artery Doppler ultrasound waveform measurements were expressed in terms of pulsatility index (PI). Biomagnetic signals (waveforms) recorded from the IUGR umbilical artery were expressed in terms of magnetic power spectral amplitudes. RESULTS: In all cases, the frequency band considered was 2 to 7 Hz. The spectral amplitudes were low (mean: 117+/-24 fT/ radical Hz) in most (90.9%) IUGR pregnancies and high (mean: 224+/-37 fT/ radical Hz) in most normal pregnancies (89.5%). There was a statistically significant difference between normal and IUGR pregnancies with respect to spectral amplitudes (p < 0.0001), Doppler PI (p < 0.0005), pH (p < 0.0005) and Apgar score (p < 0.0005). Multiple linear regression analysis revealed an influence of PI, pH and Apgar scores on the biomagnetic values (ANOVA: p < 0.0005). CONCLUSION: Our data imply that biomagnetic values of the umbilical artery flow could prove to be a helpful method for the evaluation of fetal well being especially in pregnancies complicated with preeclampsia and growth restriction. 相似文献
94.
Allogeneic blood transfusion requirements after minimally invasive versus conventional aortic valve replacement: a risk-adjusted analysis 总被引:1,自引:0,他引:1
Stamou SC Kapetanakis EI Lowery R Jablonski KA Frankel TL Corso PJ 《The Annals of thoracic surgery》2003,76(4):1101-1106
BACKGROUND: Aortic valve replacement (AVR) through a partial sternotomy (mini-AVR) has been suggested to significantly reduce postoperative morbidity compared with conventional AVR. This study sought to investigate whether mini-AVR patients require fewer transfusions than patients who had conventional AVR. METHODS: Of 511 patients who had AVR, 56 had mini-AVR and 455 had conventional AVR. A matched-case logistic regression analysis was used to adjust for these imbalances between groups. RESULTS: No patient in the mini-AVR cohort required conversion to a conventional AVR. Cardiopulmonary bypass time was longer in the mini-AVR group compared with the conventional AVR group, with a median of 102 minutes (range, 78 to 119 minutes) versus 75 minutes (range, 61 to 96 minutes; p < 0.01) in the conventional AVR group. A total of 31 patients (55%) in the mini-AVR group and 336 patients (74%) in the conventional sternotomy group required transfusions during their hospital stay (p < 0.01). After adjusting for differences in preoperative risk factors, year of operation, and surgeon, by matching on propensity score, the differences were not statistically significant (odds ratio = 0.84, 95% confidence interval = 0.40 to 1.75, p = 0.63). CONCLUSIONS: Mini-AVR produces better wound cosmesis and less surgical trauma but requires more time to perform. Matched-case analysis failed to show a significant difference in blood transfusion requirements after mini-AVR compared with the conventional AVR approach. 相似文献
95.
96.
Delichas M Psarrakos K Molyvda-Athanassopoulou E Giannoglou G Sioundas A Hatziioannou K Papanastassiou E 《European journal of radiology》2003,48(3):268-273
Medical doctors, who practice interventional cardiology, receive a noticeable radiation dose. In this study, we measured the radiation dose to 9 cardiologists during 144 procedures (72 coronary angiographies and 70 percutaneus translumined coronary angioplasties) in two Greek hospitals. Absorbed doses were measured with TLD placed underneath and over the lead apron at the thyroid protective collar. Based on these measurements, the effective dose was calculated using the Niklason method. In addition, dose area product (DAP) was registered. The effective doses, E, were normalised to the total DAP measured in each procedure, producing the E/DAP index. The mean effective dose values were found to be in the range of 1.2-2.7 microSv while the mean E/DAP values are in the range of 0.010-0.035 microSv/Gycm2. The dependence of dose to the X-ray equipment, the exposure parameters and the technique of the cardiologist were examined. Taking under consideration the laboratories' annual workload, the maximum annual dose was estimated to be 1.9 and 2.8 mSv in the two hospitals. 相似文献
97.
Sofou A Emmanouil J Peutzfeldt A Owall B 《The European journal of prosthodontics and restorative dentistry》2001,9(3-4):117-122
This study evaluated three methods of surface polishing on acrylic denture base materials. Specimens of three commercial heat-cured acrylic resin materials were finished using burs, sandpaper discs and rubber wheels, and polished with polishing soap, paste, or by application of a UV-light-activated resin sealant. The resulting surface roughness was examined by scanning electron microscopy as well as measured by means of a stylus profile Perthometer. Surface roughness was reduced by polishing. Polishing paste and UV-light-activated resin sealant were more, and equally, effective in reducing surface roughness compared to polishing soap. Polishing paste or UV-light-activated resin sealant may be used to create a smoother surface on acrylic dentures. 相似文献
98.
99.
Interferons and their application in the diseases of the lung 总被引:5,自引:0,他引:5
Interferons (IFNs) are a family of cytokine mediators that are critically involved in alerting the cellular immune system to viral infections of host cells. There are three major classes of IFNs, as follows: IFN-alpha; IFN-beta; and IFN-gamma. IFNs are being investigated and applied in various respiratory disorders, including interstitial lung diseases, lung cancer, malignant mesothelioma, malignant pleural effusions, and respiratory infections. Recent promising preliminary results concerning patients with idiopathic pulmonary fibrosis who have been treated with IFN-gamma1b should prompt the performance of further confirmatory well-designed multicenter trials. IFN-gamma is emerging as an important cytokine for use in the treatment of patients with infectious diseases, including multidrug-resistant pulmonary TB. A better understanding of IFN biology, indications, side effect profiles, and toxicity management will aid in optimizing its use in the treatment of patients. The purpose of this article is, therefore, to review the current clinical use of IFNs in the treatment of patients with respiratory diseases. 相似文献
100.
Supramalleolar osteotomy for the treatment of distal tibial angular deformities and arthritis of the ankle joint 总被引:1,自引:0,他引:1
Stamatis ED Cooper PS Myerson MS 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2003,24(10):754-764
In a 5-year period (1996-2001), the authors performed supramalleolar osteotomies for the correction of distal tibial mechanical malalignment of at least 10 degrees with concomitant pain and with or without radiographic evidence of arthritic changes. The method was also applied as an alternative to other common procedures for the treatment of a small group of patients with degenerative changes of the ankle joint without previous traumatic event and with minimal or moderately altered alignment. There were 12 patients (13 feet) with an average follow-up of 33.6 months. All osteotomies healed at an average time of 14 weeks. The average AOFAS score improved from 53.8 to 87 points, the average ankle score in the scale described by Takakura et al. improved from 56.7 to 82, and the average pain score improved from 14.6 to 32.3. In the presence of deformity, the average tibial-ankle surface angles in both the coronal and the sagittal planes were significantly improved. The radiographic degenerative changes in the ankle joint showed no evidence of progression. The choice of technique did not influence the clinical or radiographic outcome or the healing time of the osteotomy. 相似文献