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Effect of roundup and tordon 202C herbicides on antibody production in mice   总被引:1,自引:0,他引:1  
Female CD-1 mice were exposed to Tordon 202C (2,4-dichlorophenoxyacetic acid [2,4-D] and picloram) or Roundup (glyphosate) in drinking water for 26 d at concentrations ranging from 0 to 0.42% or from 0 to 1.05%, respectively. The mice were inoculated with sheep red blood cells to produce a T-lymphocyte, macrophage dependent antibody response on day 21 of the herbicide exposure period. Tordon 202C dosing reduced weight gain and water consumption at the 0.42% level of exposure. Roundup exposure did not alter weight gain or water consumption. Antibody production was unaffected by Roundup dosing, suggesting that Roundup is unlikely to cause immune dysfunction under normal application conditions. In contrast, all levels of Tordon 202C exposure reduced antibody production by as much as 45%. The immunosuppressive activity of Tordon 202C was associated with levels more than 12 x the normal application level, although it was not determined which component of the formulation was responsible for the immunosuppression effect. The presence of immune alteration subsequent to exposure to Tordon 202C at levels marginally above the normal application levels suggests that chronic exposure to Tordon 202C in the environment has the potential to alter immune function.  相似文献   
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BACKGROUND: Thoracoscopic-assisted pulmonary resection for lung cancer is controversial. The appropriateness of this approach has to be compared with the golden standard of an open resection. METHODS: This study consists of 66 patients with a clinical stage 1 disease. A thoracoscopic exploration was executed in 41 patients. Only in 16 cases was a thoracoscopic resection finally possible. The clinical and pathological TNM classification, the histological types and the surgical procedure are reported. The reasons for conversion are documented. RESULTS: To investigate the appropriateness of the thoracoscopic approach we evaluated only the pathologically proven stage 1 disease in both groups. Postoperative complications, hospital stay and survival are compared. CONCLUSION: Until now we can conclude that there is no adverse effect on survival because of the thoracoscopic approach.  相似文献   
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A fundamental question about human memory is why some experiences are remembered whereas others are forgotten. Brain activation during word encoding was measured using blocked and event-related functional magnetic resonance imaging to examine how neural activation differs for subsequently remembered and subsequently forgotten experiences. Results revealed that the ability to later remember a verbal experience is predicted by the magnitude of activation in left prefrontal and temporal cortices during that experience. These findings provide direct evidence that left prefrontal and temporal regions jointly promote memory formation for verbalizable events.  相似文献   
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PURPOSE: To help establish standards of care for transperineal interstitial permanent prostate brachytherapy (TIPPB) by obtaining data regarding current clinical practice among the most experienced TIPPB brachytherapists in the United States. METHODS AND MATERIALS: The 70 brachytherapists who performed the greatest number of TIPPB cases in 1995 in the U.S. were surveyed. Each received a comprehensive four page questionnaire that included sections on training and experience, patient and isotope selection criteria, manpower, technique, and follow-up. Thirty-five (50%) surveys were ultimately returned after three mailings and follow-up phone calls. The cumulative experience of the 35 respondents represented approximately 45% of the total TIPPB volume in the U.S. for 1995. Respondents included 29 from the private sector and six from academic programs. RESULTS: The median physician experience with TIPPB was reported as 4.9 years. Each performed an average of 73 TIPPB procedures in 1995 (range 40-300). This represented an increase in volume for most (74%) of the respondents. Sixty-three percent of the respondents attended a formal training course, 54% had TIPPB-specific residency training, and 31% had been proctored (16 had received two or more types of training experience). The most commonly reported selection criteria for implant alone was on Gleason score < or = 7, PSA < 15, < or = Stage T2a, and gland size < or = 60 cc, although no clear consensus was found. Fifty-four percent considered a history of TURP to be a relative contraindication, while 34% considered TURP to have no impact on patient selection. Eighty-six percent of respondents combine brachytherapy with external beam radiation in an average of 32% of their patients. Boosts were given with both 125I prescribed to 120 Gy (75%) or 103Pd to 90 Gy (50%). Sixty percent reported using a Mick applicator, 46% prefer using preloaded needles, and (11%) use both techniques. Real-time imaging was usually performed with ultrasound (94%); most included fluoroscopy (60%). Definitions of PSA control varied widely. CONCLUSIONS: TIPPB clinical practice in the U.S. demonstrates similarities in technique, but differences in patient selection and definitions of biochemical control. It is, therefore, incumbent on those beginning TIPPB programs to carefully review the specific practice details of those institutions with a broad experience.  相似文献   
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Prognostic risk stratification to identify perioperative and long-term cardiac risk in selected patients undergoing noncardiac surgery is part of good clinical practice. Exercise variables associated with significant increased risk include poor functional capacity (eg, <4 metabolic equivalents), marked exercise-induced ST segment shift or angina at low workloads, and inability to increase or actually decrease systolic blood pressure with progressive exercise. Approximately 40% of patients tested before peripheral vascular surgery will have an abnormal exercise electrocardiogram (ECG). The predictive value for a perioperative event, ie, death or myocardial infarction, ranges from 5% to 25% for a positive test and 90% to 95% for a negative test. Whereas exercise cardiac imaging is the modality of choice in patients with a noninterpretable exercise ECG, pharmacological stress imaging should be used in the 30% to 50% of patients who require perioperative noninvasive risk stratification and are unable to perform an adequate level of exercise to test cardiac reserve. Myocardial perfusion variables predictive of increased cardiac events include severity of the perfusion defect, number of reversible defects, extent of fixed and reversible defects, increased lung uptake of thallium-201, and marked ST segment changes associated with angina during the test. The reported sensitivity and specificity of dobutamine-induced echocardiographic wall motion abnormalities in patients with peripheral vascular disease is similar to myocardial perfusion scintigraphy, but the confidence limits are wider due to the smaller sample size in these more recent studies. In conclusion, noninvasive cardiac testing should be used selectively in patients undergoing noncardiac surgery; the results provide useful estimates of short- and long-term risk of cardiac events, and the magnitude of abnormal response on noninvasive testing should be used to formulate decisions regarding the need for coronary angiography and subsequent revascularization.  相似文献   
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PURPOSE: To evaluate neutron irradiation alone and with chemotherapy to treat inoperable pancreatic cancer. MATERIALS AND METHODS: Between 1977 and 1994, 173 patients (60 men, 113 women, aged 43-77 years [mean, 59 years]) with unresectable adenocarcinoma of the exocrine pancreas were treated, 106 with neutron irradiation alone and 67 with concomitant chemotherapy (fluorouracil [5-FU]). At follow-up, which was performed at 2-month intervals until death (range, 4-64 months), clinical status was recorded, noting the presence of overt metastasis and the onset of any major complications. Actuarial (Kaplan-Meier) survival tables were computed for both groups. RESULTS: For neutron irradiation alone and neutron irradiation plus chemotherapy, median survival times were 6 months and 9 months, respectively; actuarial survival rates at 3 years were 0 and 7%, respectively; major reactions (grade 3 or higher [scale of the Radiation Therapy Oncology Group and European Organization for Research and Treatment of Cancer]) occurred in 19 (18%) and 17 (25%) patients, respectively; and severe complications (grade 4) occurred in five (5%) and four (6%) patients, respectively. Most deaths were due to metastatic disease rather than to failure of local control. CONCLUSIONS: Neutron irradiation obliterated pancreatic adenocarcinoma at the primary site but has no effect on long-term survival. With more effective concomitant chemotherapy to prevent metastasis, local control of pancreatic cancer with neutron irradiation could lead to increased long-term survival.  相似文献   
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BACKGROUND: The leading cause of death and disability in patients suffering from aneurysmal subarachnoid hemorrhage (SAH) is cerebral vasospasm, a persistent, progressive, and often irreversible constriction of cerebral arteries. A wide array of pathological changes occur in cerebral arteries following SAH, with endothelial injury being the earliest and most consistent one. Since intact endothelium modulates many reflexes that influence vascular tone, damage to them may represent a significant contributor to cerebral vasospasm. METHODS: Changes in local cerebellar blood flow (LCBF) and pathological alterations in major cerebral arteries were studied and compared in rats at various time intervals following SAH. SAH induced by the subarachnoid injection of 0.3 ml of whole blood. Sham rats received a subarachnoid injection of 0.3 ml of isotonic saline. RESULTS: Except for an immediate but transient decrease, LCBF remained unchanged over a 3 day period following saline injection. Likewise, there were no pathological alterations in cerebral arteries of saline-injected rats. In contrast, the subarachnoid injection of whole blood produced significant changes in both LCBF and cerebral arteries. Within 30 minutes post-blood injection, LCBF became significantly decreased and remained so for 4 hours. However, within 24 hours, LCBF had returned to control levels where it remained for 3 days. Endothelial injury was observed in the basilar and middle cerebral arteries from 30 minutes through 4 hours, the same periods in which LCBF was significantly reduced. Within 24 hours, the time period in which LCBF had rebounded to control ranges, cerebral arteries showed no evidence of endothelial damage and resembled control cells. CONCLUSION: The results indicate a direct correlation between changes in LCBF and the structural integrity of endothelial cells in the early stages following SAH. The lack of chronically depressed LCBF (after 1 day) may be related to the quick structural repair of endothelium.  相似文献   
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