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71.
PURPOSE: Selection of appropriate protocols for treatment of superficial esophageal squamous cell carcinoma (SESCC) is dependent on lymph node metastasis status. Therefore, it is important to know whether lymph node metastasis is present before treatment. EXPERIMENTAL DESIGN: In this study, we examined the relation between DNA sequence copy number aberrations detected by comparative genomic hybridization and lymph node metastasis in 26 surgically resected SESCCs (training samples). We then assessed whether the genetic information is predictive for nodal status in biopsy specimens from eight newly enrolled patients with SESCC (blinded samples). RESULTS: Pathological examination revealed that 17 of 26 training samples (65.4%) did not have associated lymph node metastasis. Gains of 8q24 and/or 20q12-qter were observed in 12, including all (nine of nine) with nodal metastasis. Fourteen training samples did not have gain of either 8q24 or 20q12-qter. Of the blinded samples, two showed no gain of 8q24 or 20q12-qter, and as anticipated the postoperative pathological examination revealed no nodal metastasis. The remaining six blinded samples had gains of 8q24 and/or 20q12-qter, and lymph node metastasis was detected by postoperative examination in four of these tumors. CONCLUSIONS: Absence of gains of 8q24 and/or 20q12-qter appears to be associated with absence of lymph node metastasis in patients with SESCC; therefore, less invasive surgery can be chosen.  相似文献   
72.
PURPOSE: To evaluate the prognostic value of vascular endothelial growth factor (VEGF)-D and VEGF receptor (VEGFR)-3 in endometrial carcinoma. EXPERIMENTAL DESIGN: We assessed the levels of immunoreactivity for VEGF-D and VEGFR-3 in 71 endometrial carcinomas, 14 complex atypical endometrial hyperplasias, and 16 normal endometria by immunohistochemistry. RESULTS: VEGF-D was stained in both tumor cells and adjacent stromal cells. VEGFR-3 was stained in both tumor cells and adjacent endothelial cells. Immunoreactivity for VEGF-D in tumor cells and adjacent stromal cells became significantly stronger as lesions progressed from normal endometrium to advanced carcinoma. Similarly, immunoreactivity for VEGFR-3 in tumor cells and adjacent endothelial cells was significantly greater as lesions progressed from normal endometrium to advanced carcinoma. A strong correlation was found between high levels of VEGF-D immunoreactivity in carcinoma cells and VEGFR-3 in both carcinoma cells and adjacent endothelial cells. Similarly, high levels of VEGF-D immunoreactivity in stromal cells were significantly correlated with those of VEGFR-3 in both carcinoma cells and endothelial cells. High levels of VEGF-D in carcinoma cells and stromal cells, as well as those of VEGFR-3 in carcinoma cells and endothelial cells, were significantly related to myometrial invasion and lymph node metastasis. A strong correlation was found between poor survival and high levels of VEGF-D in both carcinoma cells and stromal cells and between poor survival and high levels of VEGFR-3 in carcinoma cells. Moreover, the high levels of VEGF-D in stromal cells and VEGFR-3 in carcinoma cells were independent prognostic factors in endometrial carcinoma. CONCLUSIONS: The presence of VEGF-D and VEGFR-3 in endometrial carcinoma may predict myometrial invasion and lymph node metastasis and may prospectively identify patients who are at increased risk for poor outcome. In addition, VEGF-D and VEGFR-3 may be promising targets for new therapeutic strategies in endometrial carcinoma.  相似文献   
73.
We investigated the effect of hypothermia on the vasodilatory response of pial arterioles to hemorrhagic hypotension. The cranial window technique was combined with microscopic video recording in an experiment involving 20 cats anesthetized with pentobarbital. The animals were randomly assigned to either a normothermic or a hypothermic group (32 degrees C). Mean arterial pressure (MAP) was reduced in stepwise increments of 10 mm Hg (from 100 to 50 mm Hg) by blood withdrawal. The diameter of small (50-100 microm) and large (100-200 microm) pial arterioles was measured. In the normothermic group (n = 9), small and large arterioles dilated at a MAP of 60 and 50 mm Hg, and at a MAP of 70, 60, and 50 mm Hg, respectively, compared with baseline values obtained at a MAP of 100 mm Hg. In contrast, in the hypothermic group (n = 11), vasodilation of either small or large arterioles was absent. The percentage diameter of small and large arterioles (percentage of control) was significantly lower at a MAP of 70, 60, and 50 mm Hg in the hypothermic group than the normothermic group. Our in vivo study demonstrates that hypothermia impairs autoregulatory vasodilation of pial arterioles in response to hemorrhagic hypotension. IMPLICATIONS: Deliberate mild hypothermia has been proposed as a means of providing cerebral protection during neurosurgical procedures. Our results suggest that cerebral blood flow autoregulation in response to hemorrhagic hypotension may be impaired during hypothermic conditions, indicating the importance of maintaining perfusion pressure during hypothermic therapy to prevent cerebral ischemia.  相似文献   
74.
The differences in hemodynamic effects of amrinone, milrinone and olprinone were evaluated in 46 patients for valvular cardiac surgery after cardiopulmonary bypass (CPB). Patients were randomly allocated to three groups; group A with amrinone infusion (17 patients); group M with milrinone infusion (15 patients); and group O with olprinone infusion (14 patients). Each drug was administrated as a single dose into the venous reservoir of the CPB circuit 15 min prior to the end of emergence from CPB, followed by continuous infusion. Hemodynamic parameters were measured at the time of preCPB (C0), just after the end of CPB (C1), one hour after the termination of CPB (C2) and after the chest closure (C3). Catecholamines were used in order of dopamine, norepinephrine and dobutamine. These doses were modulated to maintain the cardiac index > 3.0 l.min-1.m-2 by each anesthesiologist. Hemodynamic parameters (at C0, C1, C2 and C3) and the doses of cathecholamine (at C1, C2 and C3) were compared among the 3 drugs. The systolic blood pressure in group M was significantly higher than that of group A and group O after chest closure. In group M and A, the systolic blood pressure showed a significant increase after CPB. On the other hand, the systolic blood pressure showed no significant change in group O after CPB. Three drugs showed no significant difference in the dosages of catecholamines used.  相似文献   
75.
76.
High expression of SQSTM1/p62 (p62) protein, which functions as a hub for various cellular signaling pathways, has been detected in several human cancers. However, the clinicopathological impact of high p62 expression is largely unknown in epithelial ovarian cancer (EOC). Here, the expression level of p62 in primary EOCs (n=266) was assessed by immunohistochemistry, and its clinical significance was analyzed. Univariate and multivariate analyses were used to determine the impact of p62 expression on overall survival. p62 was expressed in the cytoplasm (Cyto) and/or nucleus (Nuc) in primary EOCs, and an expression subtype (CytoHigh/NucLow), showing high expression in the cytoplasm but low expression in the nucleus, was significantly correlated with serous carcinoma (P<0.001), advanced stage (P=0.005), presence of residual tumor (P<0.001), and low overall survival rate (P=0.013). Furthermore, in serous carcinomas (n=107), the p62 CytoHigh/NucLow subtype was significantly correlated with low overall survival rate (P=0.019) as an independent factor (P=0.044). Thus, our findings suggest that high expression of cytoplasmic p62 may be a novel prognostic biomarker in EOC, particularly in serous carcinoma.  相似文献   
77.
To evaluate the dosimetric impact of respiratory breast motion and daily setup error on whole breast irradiation (WBI) using three irradiation techniques; conventional wedge (CW), field-in-field (FIF) and irregular surface compensator (ISC). WBI was planned for 16 breast cancer patients. The dose indices for evaluated clinical target volume (CTVevl), lung, and body were evaluated. For the anterior-posterior (AP) respiratory motion and setup error of a single fraction, the isocenter was moved according to a sine function, and the dose indices were averaged over one period. Furthermore, the dose indices were weighted according to setup error frequencies that have a normal distribution to model systematic and random setup error for the entire treatment course. In all irradiation techniques, AP movement has a significant impact on dose distribution. CTVevlD95 (the minimum relative dose that covers 95 % volume) and V95 (the relative volume receiving 95 % of the prescribed dose) were observed to significantly decrease from the original ISC plan when simulated for the entire treatment course. In contrast, the D95, V95 and dose homogeneity index did not significantly differ from those of the original plans for FIF and CW. With regard to lung dose, the effect of motion was very similar among all three techniques. The dosimetric impact of AP respiratory breast motion and setup error was largest for the ISC technique, and the second greatest effect was observed with the FIF technique. However, these variations are relatively small.  相似文献   
78.
79.
The aim of this study was to estimate the efficacy of contrast-enhanced ultrasound (CEUS) in detecting postpartum hemorrhage (PPH) after cesarean section. This is the first study of CEUS in obstetric hemorrhage. A total of 37 patients, operated at Nagoya University Hospital, underwent CEUS. We evaluated the findings of CEUS, which were qualitatively defined as positive when pooling or leakage of contrast agent was observed in the uterine cavity, by measuring the amount of bleeding during the first 4 h after cesarean section. The time–intensity curve patterns of leaked contrast agents were also analyzed for quantitative prediction of the amount of blood loss. Significant differences between the excessive hemorrhage (N = 7) and non-excessive hemorrhage groups (N = 30) were noted in the occurrence of positive CEUS (p = 0.011). Additionally, mean postpartum blood loss markedly increased in patients with a positive CEUS (p = 0.002). From a quantitative perspective, the time until leakage of contrast agents was detected correlated with the amount of bleeding, but the other characteristics of the time–intensity curve pattern did not provide valuable information. In conclusion, CEUS, which enables bedside assessment and rapid diagnosis, is a promising strategy for the detection of PPH.  相似文献   
80.
Baculovirus infection of Sf9 cells at high densities, such as during mid- and late exponential phase, often results in a significant reduction of protein yield per cell, compared to the early exponential phase. Nutrient depletion has been considered as a major cause for the decreased protein yield. In this study, we report that the addition of nutrients (glucose, yeastolate ultrafiltrate, and lactalbumin hydrolysate) and small fraction of fresh medium at time of infection restores the expression level of actin and myosin V?CHMM at late exponential phase (11.3?×?106?cells/ml) to that at early exponential phase (1.0?×?106?cells/ml). The relative yields of actin and myosin V?CHMM were approximately equal at both phases (typically 200?mg of actin and 5?mg of myosin V?CHMM per 1010?cells), i.e., the volumetric yield of proteins from the cell culture at late exponential phase was approximately tenfold higher than at early exponential phase. The functionality of the recombinant actin and myosin V?CHMM was confirmed by measuring the rate of actin polymerization, actin-activated ATPase, and the gliding velocity of actin filaments in an in vitro motility assay.  相似文献   
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