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AIM: To establish the association between lymph node involvement and the response to neoadjuvant therapy in locally advanced rectal cancer.METHODS: Data of 130 patients with mid and low locally advanced rectal adenocarcinoma treated with neoadjuvant chemoradiation followed by radical surgery over a 5-year period were reviewed. Tumor staging was done by endorectal ultrasound and/or magnetic resonance imaging. Tumor response to neoadjuvant therapy was determined by T-downstaging and tumor regression grading (TRG). Pathologic complete response (pCR) is defined as the absence of tumor cells in the surgical specimen (ypT0N0). The varying degrees TRG were classified according to Mandard’s scoring system. The evaluation of the response is based on the comparison between previous clinico-radiological staging and the results of pathological evaluation. χ2 and Spearman’s correlation tests were used for the comparison of variables.RESULTS: Pathologic complete response (pCR, ypT0N0, TRG1) was observed in 19 cases (14.6%), and other 18 (13.8%) had only very few residual malignant cells in the rectal wall (TRG2). T-downstaging was found in 63 (48.5%). Mean lymph node retrieval was 9.4 (range 0-38). In 37 cases (28.5%) more than 12 nodes were identified in the surgical specimen. Preoperative lymph node involvement was seen in 77 patients (59.2%), 71 N1 and 6 N2. Postoperative lymph node involvement was observed in 41 patients (31.5%), 29 N1 and 12 N2, while the remaining 89 were N0 (68.5%). In relation to ypT stage, we found nodal involvement of 9.4% in ypT0-1, 22.2% in ypT2 and 43.7% in ypT3-4. Of the 37 patients considered “responders” to neoadjuvant therapy (TRG1 and 2), there were only 4 N+ (10.8%) and the remainder N0 (89.2%). In the “non responders” group (TRG 3, 4 and 5), 37 cases were N+ (39.8%) and 56 (60.2%) were N0 (P < 0.001).CONCLUSION: Response to neoadjuvant chemoradiation in rectal cancer is associated with lymph node involvement.  相似文献   
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We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range.  相似文献   
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The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase.  相似文献   
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Amikacin levels in serum and tissues were determined in 115 Wistar rats, 70 with normal renal function (NRF) and the remaining 45 with terminal renal impairment (TRI). The results obtained in the animals with NRF show an accumulation of the antibiotic in all the tissues studied as compared with plasma levels, specially in the renal cortex and medulla. In the rats with TRI important alterations in the plasma and tissue kinetics of the antibiotics were observed. The plasma kinetics of amikacin in rats with TRI are characterised by significant alterations in the pharmacokinetic parameters, specially those defining the distribution processes of the antibiotic. In the tissues of the latter, a significant increase in the antibiotic concentration takes place, particularly in the renal cortex. The average half-lives of the antibiotic in the tissues of rats with TRI increase compared with the group of rats with NRF, though the difference are not so significant as in the case of the plasma half-life. The use of a specific kinetic distribution model, with linear and non-linear tissue binding, showed that significant variations occur in the partition coefficient and in the Michaelis-Menten parameters, which characterize the saturable binding of Amikacin to tissue in rats with NRF and TRI.  相似文献   
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This paper reports a test of the efficacy of Familias Unidas, a Hispanic-specific, ecologically focused, parent-centered preventive intervention, in promoting protection against and reducing risk for adolescent behavior problems. Specifically, the intervention was designed to foster parental investment, reduce adolescent behavior problems, and promote adolescent school bonding/academic achievement, all protective factors against drug abuse and delinquency. One-hundred sixty seven Hispanic families of 6th and 7th grade students from three South Florida public schools were stratified by grade within school and randomly assigned to intervention and no-intervention control conditions. Results indicated that Familias Unidas was efficacious in increasing parental investment and decreasing adolescent behavior problems, but that it did not significantly impact adolescent school bonding/academic achievement. Summer-vacation rates of adolescent behavior problems were six times higher in the control condition than in the intervention condition. Furthermore, change in parental investment during the intervention was predictive of subsequent levels of adolescent behavior problems. The findings suggest that Familias Unidas is efficacious in promoting protection and reducing risk for adolescent problem behaviors in poor immigrant Hispanic families.  相似文献   
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Two pregnancies in a patient with a fixed-rate pacemaker are reported. The first pregnancy was uneventful. The second had no maternal complications either. A moderate tachysystolia was detected during the second period. The newborn was delivered with forceps applied under spinal anesthesia. Newborn infant evolution presented no hazards, but umbilical cord analysis revealed a severe acidosis, in spite of a normal scalp analysis 45 min earlier. Epidural anesthesia is recommended for such patients.  相似文献   
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