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A great deal of controversy surrounds the question of the effectiveness of treatment of breast carcinoma, particularly radical surgical procedures in early cases.The results of simple mastectomy followed by radiotherapy are compared with those of radical surgery in two series of cases, in Edinburgh and at the Mayo Clinic, respectively; despite the many variables involved in such a comparison, the figures are of interest because of their similarity.Endocrine therapy in metastasizing breast cancer has profoundly altered malignant growth in some cases. Hypophysectomy is gaining favor and appears to be superseding adrenalectomy. 相似文献
45.
Preoperative glucocorticoids decrease pulmonary hypertension in piglets after cardiopulmonary bypass and circulatory arrest 总被引:3,自引:0,他引:3
Pearl JM Schwartz SM Nelson DP Wagner CJ Lyons JM Bauer SM Duffy JY 《The Annals of thoracic surgery》2004,77(3):994-1000
BACKGROUND: Glucocorticoids during cardiopulmonary bypass benefit pediatric patients undergoing repair of congenital heart defects and are routine therapy, but underlying mechanisms have not been fully examined. The hypothesis was that glucocorticoids could improve cardiopulmonary recovery after cardiopulmonary bypass and deep hypothermic circulatory arrest. METHODS: Crossbred piglets (5 to 7 kg) were cooled with cardiopulmonary bypass, followed by 120-min deep hypothermic circulatory arrest. Animals were then warmed to 38 degrees C, removed from bypass, and maintained for 120 min. Methylprednisolone (60 mg/kg) was administered in the cardiopulmonary bypass pump prime (intraoperative glucocorticoids) or 6 hours before bypass (30 mg/kg) in addition to the intraoperative dose (30 mg/kg; preoperative and intraoperative glucocorticoids). Controls (no glucocorticoids) received saline. RESULTS: Pulmonary vascular resistance in controls increased from a baseline of 152 +/- 40 to 364 +/- 29 dynes. s/cm(5) at 2 hours of recovery (p < 0.001). Intraoperative glucocorticoids did not alleviate the increase in pulmonary vascular resistance (301 +/- 55 dynes. s/cm(5) at 2 hours of recovery, p < 0.001). However, animals receiving pre and intraoperative glucocorticoids had no increase in pulmonary vascular resistance (155 +/- 54 dynes. s/cm(5)). Plasma endothelin-1 in controls increased from 1.3 +/- 0.2 at baseline to 9.9 +/- 2.0 pg/mL at 2 hours recovery (p < 0.01), whereas glucocorticoid-treated animals had lower endothelin-1 levels (4.5 +/- 2.1 pg/ml, preoperative and intraoperative glucocorticoids; 4.9 +/- 1.7 pg/mL, intraoperative glucocorticoids) at the end of recovery (p < 0.05). Intracellular adhesion molecule-1 in lung tissue was lower in animals receiving pre and intraoperative glucocorticoids (p < 0.05). Myeloperoxidase activity was elevated in control lungs at 2 hours of recovery compared with glucocorticoid-treated groups (p < 0.05). Inhibitor kappaBalpha, the inhibitor of nuclear factor-kappaB, was higher in lungs of animals receiving glucocorticoids compared with controls (p < 0.05). CONCLUSIONS: Glucocorticoids prevented pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest, which was associated with reduced plasma endothelin-1. Glucocorticoids also reduced pulmonary intercellular adhesion molecule-1 and myeloperoxidase activity. Inhibition of nuclear factor-kappaB, along with reduced neutrophil activation, contributed to glucocorticoid alleviation of pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest. 相似文献
46.
Sildenafil citrate alleviates pulmonary hypertension after hypoxia and reoxygenation with cardiopulmonary bypass 总被引:3,自引:0,他引:3
Lyons JM Duffy JY Wagner CJ Pearl JM 《Journal of the American College of Surgeons》2004,199(4):607-614
BACKGROUND: Sudden reoxygenation of hypoxic neonates undergoing cardiac operation exacerbates the systemic inflammatory response to cardiopulmonary bypass secondary to reoxygenation injury, worsening cardiopulmonary dysfunction. Reports suggest sildenafil decreases pulmonary hypertension and may affect myocardial function. Sildenafil's efficacy for treating postbypass cardiopulmonary dysfunction remains unknown. STUDY DESIGN: Fourteen neonatal piglets (5 to 7 kg) underwent 90 minutes of hypoxia, 60 minutes of reoxygenation with cardiopulmonary bypass, and 120 minutes of recovery. Six animals received 50 mg oral sildenafil and eight received saline at hypoxia. Data are presented as mean +/- SD. RESULTS: Sildenafil prevented the high pulmonary vascular resistance observed in controls (controls baseline 81 +/- 37 dynes. s/cm(5) versus recovery 230 +/- 93 dynes. s/cm(5), p = 0.004; sildenafil baseline 38 +/- 17 dynes. s/cm(5) versus recovery 101 +/- 60 dynes. s/cm(5), p = 0.003). Despite lower pulmonary vascular resistance after sildenafil, arterial endothelin-1 (ET-1) was increased in both groups (control baseline 1.3 +/- 0.5 pg/mL versus recovery 4.5 +/- 3.7 pg/mL, p = 0.01; sildenafil baseline 1.3 +/- 0.3 pg/mL versus recovery 9.8 +/- 4.9 pg/mL, p = 0.003). Intravenous nitric oxide (NO) levels were preserved after sildenafil treatment (sildenafil baseline 340 +/- 77 nM versus recovery 394 +/- 85 nM). IV NO levels in controls were decreased when compared with baseline (control baseline 364 +/- 83 nM versus recovery 257 +/- 97 nM, p = 0.028). Although levels of exhaled NO decreased in both groups, the sildenafil-treated animals had higher levels of exhaled NO when compared with controls at the end of recovery (0.6 +/- 0.4 parts per billion versus 1.8 +/- 0.9 parts per billion, respectively, p = 0.029). CONCLUSIONS: Sildenafil alleviated pulmonary hypertension after reoxygenation with cardiopulmonary bypass. Despite increased ET-1 levels, pulmonary vascular resistance was lower with sildenafil treatment, suggesting sildenafil's effect on the pulmonary vasculature is capable of countering vasoconstriction by ET-1. Further study into the role of sildenafil in perioperative therapy and its interactions with ET-1 are warranted. 相似文献
47.
Mahmud T Lyons MC Naudie DD Macdonald SJ McCalden RW 《Clinical orthopaedics and related research》2012,470(10):2730-2736
Background
Periprosthetic joint infection has been the leading cause of failure following TKA surgery. The gold standard for infection control has been a two-staged revision TKA. There have been few reports on mid- to long-term survivorship, functional outcomes, and fate of patients with a failed two-stage revision TKA. 相似文献48.
The present research moved beyond focusing on negative dispositions to investigate the influence of positive aspects of personality, namely extraversion and openness, on stress responses including appraisals, affect and task performance. Challenge appraisals occur when stressor demands are deemed commensurate with coping resources, whereas threat appraisals occur when demands are believed to outweigh coping resources. We examined the unique influence of personality on stress responses and the mediating role of appraisals. Personality was assessed, and then participants (N = 152) were exposed to a validated math stressor. We found unique effects on stress responses for neuroticism (high threat and negative affect and low positive affect), extraversion (high positive and low negative affect) and openness (high positive and low negative effect and better performance). Mediation analyses revealed that neuroticism indirectly worsened performance, through threat appraisals, and that openness indirectly increased positive affect through lower threat. These findings highlight the importance of investigating multiple aspects of personality on stress responses and provide an avenue through which stress responses can be changed—appraisals. Only by more broad investigations can interventions be tailored appropriately for different individuals to foster stress resilience. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
49.
A 55-year-old woman had recurrent bouts of low substernal and epigastric pain radiating into the interscapular region. A hepatobiliary scan initially showed what was believed to be a dilated common bile duct and nonvisualization of the gallbladder. A delayed image obtained after having the patient move about revealed the presence of a filled gallbladder and normal common bile duct. The combination of recurrent pain with this scintigraphic picture may be representative of a floating gallbladder or an incomplete torsion with spontaneous detorsion. This case is presented to describe the scintigraphic appearance of a mobile gallbladder that may be prone to volvulus and to emphasize the importance of obtaining decubitus or oblique views at the end of a hepatobiliary study in selected cases of unusual findings. 相似文献
50.
Inhibition of Repair of Radiation-induced DNA Damage by Thermal Shock in Chinese Hamster Ovary Cells
R.L. Warters B.W. Lyons J. Axtell-Bartlett 《International journal of radiation biology》2013,89(3):505-517
SummaryThe effect of exposure to elevated temperatures (41–45°C) on the repair of radiation-induced DNA strand breaks was measured in monolayer cultured Chinese hamster ovary (CHO) cells. Prior exposure of cells to temperatures between 43 and 45°C resulted in significant decreases in the rate of repair of DNA damage. Exposure to 45°C for 15 min slowed the rate of DNA repair to 0·17 of the control repair rate. The To for inactivation of DNA repair was observed to be 34, 13 and 6 min at 43, 44 and 45°C, respectively. Stepdown-heating (45°C for 15 min followed by repair at 41°C) resulted in greater inhibition of DNA repair (0·11 of the control rate) than was observed after acute heating alone. Repair at 41°C was observed to proceed in unheated cells at a faster rate than at 37°C. An Arrhenius analysis of the inactivation kinetics of DNA repair between 43 and 45°C indicated an activation energy of 140 kcal mol?1 of protein for the inhibition of DNA repair. In general, the results were inconsistent with either a retardation of the DNA repair rate or an increase in unrepaired DNA lesions being responsible for heat-induced radiosensitization. 相似文献