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The present study was performed in order to investigate the possible association of the -418 G/C polymorphism in the tissue inhibitor of metalloproteinase-2 (TIMP-2) gene, which affects its expression, with the risk of developing oral cancer. PCR-based restriction analysis was performed in DNA samples from 158 patients with oral squamous cell carcinoma (OSCC) and 168 healthy controls of equivalent sex, age and ethnicity (Greeks and Germans). Statistical analyses were performed with Fisher's exact test and the calculation of odds ratios with a 95% confidence interval (CI). The frequency of the low C allele expression was ten times greater in the patients than the controls (31% vs 2.7%, respectively; P<0.001). The C/C and G/C genotypes were associated with an increased risk of developing OSCC (P<0.001, OR=40.88, 95% CI=2.24-744.40, and P<0.001, OR=21.31, 95%=9.82-46.21, respectively). The same pattern of significant differences with the controls was also observed in the subgroups of patients in regard to the initial or advanced stages of oral cancer, family history of any type of cancer or thrombosis, and smoking habits or alcohol abuse. These findings are consistent with the reduced levels of TIMP-2 in the presence of the low expression C allele, which are insufficient to inhibit the matrix metalloproteinase-driven degradation of the extracellular matrix (leading to cancer invasion) and mitogen-driven neoangiogenesis (leading to tumor growth and metastasis). In conclusion, the studied TIMP-2 polymorphism is strongly associated with an increased risk of OSCC in Europeans carrying the low C allele expression. These results indicate that this polymorphism could serve as a genetic marker for the susceptibility of cancer in the oral cavity.  相似文献   
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Angiogenesis seems to contribute to tumor growth and the development of metastases. There may be an association between the vascular density of individual tumors and their prognosis. In the present survey we studied 53 cases of renal cell carcinoma investigating possible relationship between histologic grade and microvessel density (MVD) measured by an image analysis system. According to our results MVD was significantly associated with the histologic grade, higher grades being accompanied with a higher MVD. Further studies are needed to investigate a possible connection of MVD with the prognostic role of grade in RCCs.  相似文献   
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The association between endogenous LH concentrations during ovarian stimulation in a gonadotrophin-releasing hormone (GnRH) antagonist protocol and pregnancy likelihood was examined in a large combined analysis of individualized patient data obtained after treatment with recombinant FSH and a GnRH antagonist prior to IVF/intracytoplasmic sperm injection. Data from 1764 patients from six randomized controlled trials were pooled for retrospective analysis. Ongoing pregnancy and miscarriage rates for patients stratified by LH percentiles were assessed. Patients in the lowest LH quartile (< P25) were younger with a higher predicted ovarian reserve and response compared with patients in the highest quartile (> P75). With adjustment for identified predictive factors of pregnancy, estimated odds ratios (95% confidence interval) for ongoing pregnancy for LH categories < P25 versus ≥ P25, > P75 versus ≤ P75 and < P25 versus > P75 were 0.96 (0.75-1.22), 1.13 (0.88-1.45) and 0.89 (0.66-1.21) on stimulation day 8, and 0.96 (0.76-1.21), 1.03 (0.82-1.30) and 0.95 (0.72-1.26) on the day of human chorionic gonadotrophin, respectively. No significant differences in pregnancy or miscarriage rates between the LH categories were observed. Endogenous LH concentrations have no association with the likelihood of ongoing pregnancy in women undergoing ovarian stimulation using a recombinant FSH/GnRH antagonist protocol.  相似文献   
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Background  The decision to proceed to simple underwater seal drainage or apply active suction to the underwater seal after lung resection is mostly based on surgeon preference. The purpose of this study was to test whether routine application of active suction is necessary after lobectomy. Patients and methods  This was a prospective randomized controlled trial conducted in the Patras University Hospital. Ninety-one patients who underwent lobectomy or bilobectomy for lung cancer and met the eligibility criteria were enrolled. Group I included 47 patients and group II had 44 patients. The two groups were comparable. At the end of surgical procedure patients were randomly assigned to receive −15 to −20 cm H2O active suction applied to the underwater seal drainage (group I) or simple underwater seal drainage (group II). The primary end point was the time elapsed between placement and removal of drains. Results  No statistically significant differences were observed between the two groups in terms of time elapsed between the removal of chest drains, mortality, morbidity, adequacy of drainage system, and postoperative hospital stay. Suction applied to the underwater seal to re-expand the lung succeeded in 3 of 10 cases of persistent pneumothorax in group II. Discontinuing suction in 7 patients with persistent air leak in group I resulted in leak resolution in 4 patients. Conclusions  Routine application of active drain suction to the underwater seal is not necessary after lobectomy. However, it could be useful in persistent pneumothorax with sufficient air entry in the lung and clear airways. It is of no help in persistent air leaks when the lung is expanded.  相似文献   
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Abstract   Background: Aortic arch surgery is impossible without the temporary interruption of brain perfusion and therefore is associated with high incidence of neurologic injury. The deep hypothermic circulatory arrest (HCA), in combination with antegrade or retrograde cerebral perfusion (RCP), is a well-established method of brain protection in aortic arch surgery. In this retrospective study, we compare the two methods of brain perfusion. Materials and Methods: From 1998 to 2006, 48 consecutive patients were urgently operated for acute type A aortic dissection and underwent arch replacement under deep hypothermic circulatory arrest (DHCA). All distal anastomoses were performed with open aorta, and the arch was replaced totally in 15 cases and partially in the remaining 33 cases. Our patient cohort is divided into those protected with antegrade cerebral perfusion (ACP) (group A, n = 23) and those protected with RCP (group B, n = 25). Results: No significant difference was found between groups A and B with respect to cardiopulmonary bypass-time, brain-ischemia time, cerebral-perfusion time, permanent neurologic dysfunction, and mortality. The incidence of temporary neurologic dysfunction was 16.0% for group A and 43.50% for group B (p = 0.04). The mean extubation time was 3.39 ± 1.40 days for group A and 4.96 ± 1.83 days for group B (p = 0.0018). The mean ICU-stay was 4.4 ± 2.3 days for group A and 6.9 ± 2.84 days for group B (p = 0.0017). The hospital-stay was 14.38 ± 4.06 days for group A and 19.65 ± 6.91 days for group B (p = 0.0026). Conclusion: The antegrade perfusion seems to be related with significantly lower incidence of temporary neurological complications, earlier extubation, shorter ICU-stay, and hospitalization, and hence lower total cost.  相似文献   
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The aim of this study was to examine the reproducibility of the new indicator test for sudomotor function (Neuropad) in type 2 diabetic patients. The study included 142 type 2 diabetic patients (70 men) with a mean age of 67.3 +/- 7.6 years and a mean diabetes duration of 14.2 +/- 6.3 years. Sudomotor function was assessed by means of colour change in the indicator test. Each patient was examined twice. Moreover, inter-observer variability was assessed in 60 patients (35 patients with sudomotor dysfunction, 25 patients without sudomotor dysfunction). In the right foot, a highly significant (r = 0.91, p = 0.001) correlation was observed between time until complete colour change of the test on the first (910.7 +/- 431.6 seconds) and second examination (935.8 +/- 440.1 seconds). In the left foot, a highly significant (r = 0.89, p = 0.001) correlation was observed between time until complete colour change of the test on the first (911.6 +/- 430.3 seconds) and second examination (940.5 +/- 441.2 seconds). Reproducibility was excellent both in patients with sudomotor dysfunction (p = 0.001) and in those without sudomotor dysfunction (p = 0.001). Agreement in diagnosis of sudomotor dysfunction between the two examinations was 98 %. Inter-observer reproducibility was excellent (p = 0.001), both in patients with sudomotor dysfunction and in those without sudomotor dysfunction. Intra- and interobserver Coefficient of Variance ranged between 4.1 % and 5.1 %. CONCLUSIONS: These results indicate that reproducibility of the new indicator test for sudomotor function is excellent in type 2 diabetic patients with or without sudomotor impairment.  相似文献   
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