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71.
Kymionis GD Aslanides IM Siganos CS Pallikaris IG 《Journal of cataract and refractive surgery》2004,30(1):230-233
A 42-year-old man had Intacs (Addition Technology Inc.) implantation for early pellucid marginal degeneration (PMD). Two Intacs segments (0.45 mm thickness) were inserted uneventfully in the fashion typically used for low myopia correction (nasal-temporal). Eleven months after the procedure, the uncorrected visual acuity was 20/200, compared with counting fingers preoperatively, while the best spectacle-corrected visual acuity improved to 20/25 from 20/50. Corneal topographic pattern also improved. Although the results are encouraging, concern still exists regarding the long-term effect of this approach for the management of patients with PMD. 相似文献
72.
Giatromanolaki A Koukourakis MI Kakolyris S Mavroudis D Kouroussis C Mavroudi C Perraki M Sivridis E Georgoulias V 《International journal of cancer. Journal international du cancer》2004,108(4):620-627
The assessment of tumor molecular features in combination with the detection of occult malignant cells may provide important clinical information, beyond the standard staging of breast cancer. Using a nested RT-PCR technique, we assessed prospectively the presence of cytokeratin-19 (CK19) mRNA positive cells in the blood of 100 operated patients with breast cancer before the initiation of adjuvant chemotherapy and local radiotherapy. Tissue samples were prospectively collected and analyzed for estrogen (ER) and progesterone (PgR) receptor, c-erbB-2 overexpression, mutant-p53 and bcl-2 protein accumulation, proliferation index and microvessel density (MVD). CK-19 mRNA-positive cells were detected in the peripheral blood of 33% of patients. Simultaneous display of high intratumoral MVD and of CK-19 mRNA-positive cells, which characterized highly angiogenic and disseminated in the peripheral blood (HAD) disease was noted in 25% of patients. Detection of CK-19 positive cells was significantly associated with increased MVD (p = 0.002). In univariate analysis (median follow-up 30 months) CK19 mRNA detection and MVD were the most significant factors related to a short relapse-free survival (RFS), (p < 0.0001). In multivariate analysis, CK19 positivity, high MVD and c-erbB-2 overexpression were the only significant and independent variables associated with relapse (p = 0.0005, 0.03 and 0.04, respectively). Patients with HAD had an expected relapse rate close to 70% vs. <5% in the remaining patients irrespectively of the used chemotherapy regimen. The simultaneous presence of high MVD and CK19-positive cells in the blood of patients with early breast is linked with poor prognosis, which cannot be improved with standard chemotherapy regimens. 相似文献
73.
74.
In the present study, using the mental chronometry paradigm, we examined the hypothesis that during motor imagery the brain uses a forward internal model of arm inertial properties to predict the motion of the arm in different dynamic states. Seven subjects performed overt and covert arm movements with one (motion around the shoulder joint) and two (motion around both the shoulder and elbow joints) degrees of freedom in the horizontal plane. Arm movements were executed under two loading conditions: without and with an added mass (4kg) attached to the subject's right wrist. Additionally, movements were performed in two different directions, condition which implies changes in the arm inertia due to the inertial anisotropy of the arm. Our analysis was focused on the timing features of overt and covert movements measured by means of an electronic stopwatch. Durations of right-direction arm movements (low inertial resistance) were smaller compared to durations of left-direction arm movements (high inertial resistance). Additionally, loading the arm with an added mass of 4kg significantly changed the dynamics of motion: movements were indeed more prolonged under loaded conditions. In both cases, the duration of simulated movements mirrored that of overtly executed movements. Therefore, neither the inertial anisotropy of the arm nor the addition of an external mass affected the timing correspondence between overt and covert movement execution. These findings suggest that the brain internally represents the inertial properties of the arm and makes use of it both for sensorimotor control and for the generation of motor images. 相似文献
75.
Anastasiou CA Kavouras SA Koutsari C Georgakakis C Skenderi K Beer M Sidossis LS 《International journal of sport nutrition and exercise metabolism》2004,14(6):609-625
This study examined the effect of maltose-containing sports drinks on exercise performance. Ten subjects completed 4 trials. Each trial consisted of a glycogen depletion protocol, followed by a 15-min refueling, after which subjects performed an 1-h performance test while consuming one of the experimental drinks (HGlu, glucose; HMal, maltose; MalMix, sucrose, maltose, and maltodextrin; Plac, placebo). Drinks provided 0.65 g/kg body weight carbohydrates during refueling and 0.2 g/kg every 15 min during the performance test. Although no significant differences were found in performance (HGlu: 67.2 +/- 2.0; HMal: 68.6 +/- 1.7; MalMix: 66.7 +/- 2.0; Plac: 69.4 +/- 3.0 min, P> 0.05), subjects completed the MalMix trial 3.9%; faster than the Plac. Carbohydrate drinks caused comparable plasma glucose values that were significantly higher during refueling and at the end of exercise, compared to Plac. The data suggest that although carbohydrate drinks help to maintain plasma glucose at a higher level, no differences in performance could be detected after glycogen-depleting exercise. 相似文献
76.
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
77.
PURPOSE: To report a case of Parinaud's oculoglandular syndrome (POS) in which, despite the initially negative, a late onset of serologic positive titers was observed. METHODS: Case report. RESULTS: A 65-year-old man was examined for a foreign body in the left eye associated with granulomatous nodule on the palpebral conjuctiva, chemosis and a swollen preauricular lymph node. Despite the initially negative serologic titers to Bartonella henselae, a clinical diagnosis of POS was made and treatment was instituted initially with oral ciprofloxacin (500 mg twice a day). Three weeks later, serologic positive titers were found which confirmed the diagnosis of POS. CONCLUSION: Even though the improvements in diagnostic testing such as indirect immunofluorescence antibody, negative titles could be initially observed, confusing the diagnostic process. Other techniques (such as polymerase chain reaction (PCR) testing) should be also taken into consideration in cases with increased clinical suspicious of B. henselae indections. 相似文献
78.
Papalambros E Sigala F Georgopoulos S Menekakos C Giatromanolaki A Bastounis E Sivridis E 《International journal of molecular medicine》2003,12(6):965-968
Our purpose was to investigate the expression of matrix metalloproteinase (MMP)-2 and -9 in all types of abdominal aortic aneurysms (AAA): symptomatic, asymptomatic, and ruptured. MMP-2 and -9 activity was investigated in surgical samples from the arterior wall of 46 AAA, using a standard immunohistochemical technique. The MMP-9 activity was significantly higher in large AAA (>6 cm), but there was no relation between AAA size and MMP-2 activity. Neither MMP-2 nor MMP-9 were related with AAA rupture, other complications or symptoms. The MMP-9 activity in AAA is a determinant of the aneurysm size, but it is not related to clinical manifestations. 相似文献
79.
80.
Charisios Karanikiotis Michail Daniilidis Nikolaos Karyotis Charalambos Bakogiannis Theofanis Economopoulos Samuel Murray Demetris Papamichael Epaminondas Samantas Angelos Nikolaou Lemonia Skoura Nikolaos Tselis Nikolaos Zamboglou George Fountzilas MD 《Strahlentherapie und Onkologie》2008,184(6):325-331
BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) represents a seldom malignancy in most developed countries. Nevertheless, NPC receives an endemic form in concrete racial entities. The aims of this study were to detect the presence of Epstein-Barr virus DNA (EBV-DNA) in peripheral blood of NPC patients, to molecularly define human leukocyte antigens (HLA) DRB1*, DQA1* and DQB1* allele frequencies, and, finally, to determine whether the genetic predisposition of an individual to NPC depends on the liability to EBV infection. PATIENTS AND METHODS: A total of 101 patients of Hellenic origin and nationality, with histologically proven NPC, participated in this study. EBV-DNA detection was also applied in 66 patients with EBV-related malignancies (Hodgkin's [HL] and non-Hodgkin's lymphoma [NHL]) and infectious mononucleosis (IM), as well as in 80 healthy EBV-seropositive controls. RESULTS: 81% of the NPC patients, 77.8% with HL, 72.2% with NHL, and 66.7% with IM were EBV-DNA positive, whereas the EBV genome was detected only in 15% of the healthy controls. These differences were statistically significant in all cases. Analysis of HLA class II antigens showed decreased frequency of the DRB1*07 (p = 0.003), DQA1*0103 (p = 0.002), and DQA1*0201 (p = 0.003) alleles among NPC patients. A significant association between the HLA-DR/DQ alleles and the presence of EBV-DNA in peripheral whole blood was not established. CONCLUSION: Circulating EBV-DNA and specific HLA class II alleles may predispose to or protect from NPC. However, the results of this study suggest that the genetic predisposition of an individual to NPC is independent of the liability to EBV infection. 相似文献