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901.
A single and simple procedure for the determination of both carbendazim and imazalil is described. The proposed analytical methodology is based on a liquid-liquid extraction with ethyl acetate and further analysis with HPLC-UV in the case of carbendazim, and GC-nitrogen-phosphorus detection in the case of imazalil. Detection levels have been 0.01 mg/kg for carbendazim and 0.005 mg/kg for imazalil. Recoveries have been no less than 77% for carbendazim and 92% for imazalil. The method has been validated with fortified samples at different concentration levels. Different confirmation criteria have been studied and applied in routine analysis. The analytical procedure proposed has been applied to the analysis of 200 fruit samples belonging to the Residue Monitoring of Hygiene Food Program 1995 of the Spanish Ministry of Health, which has been performed in our laboratory. The results obtained have confirmed the viability of the method in routine analysis for these pesticides. A first evaluation of the presence of residues of both fungicides in fruits produced in Spain has been made.  相似文献   
902.
PURPOSE: A new method of palliation of malignant obstructive jaundice is presented. METHODS AND MATERIALS: Twelve patients with carcinoma of the extrahepatic bile ducts (EHBD-five patients) or pancreatic head (PH-seven patients) received radiation therapy between 1988 and 1991. Percutaneous transhepatic biliary drainage was performed in four EHBD patients and an endoprosthesis was placed during endoscopic retrograde cholangiopancreatography (ERCP) in the other eight patients. All 12 received intraluminal brachytherapy (ILBT): 20-50 Gy calculated at 1 cm from the Iridium-192 (192Ir) wire. In four PH patients the source was placed in the duct of Wirsung; in the other eight patients ILBT was performed via the common bile duct. Five of the seven PH patients and one of the five EHBD patients received External Beam Radiation Therapy (EBRT): 26-50 Gy, alone or with concomitant 5-Fluorouracil (5-FU). RESULTS: Cholangitis occurred in six patients. Three PH patients treated with EBRT+ILBT developed gastrointestinal toxicities. With a minimum follow-up of 18 months, median survival times were 14 months (EHBD) and 11.5 months (PH); one of the seven PH patients is alive (29 months) and two of the EHBD patients are alive (18 and 43 months). All patients had satisfactory control of jaundice. CONCLUSIONS: The results in the EHBD patients suggest that the addition of ILBT after biliary drainage prolongs survival. Further experience is necessary to determine whether ILBT in the common bile duct and/or in the duct of Wirsung may be, in PH patients, an alternative boost technique to Interstitial Brachy-therapy (IBT) or Intraoperative Electron Beam Radiation Therapy (IOEBRT).  相似文献   
903.
904.
The authors describe the use of the ESR technique during the past 20 years. There are many examples of the application of the technique in different investigations. The authors propose the new way of training medical students to apply it.  相似文献   
905.
906.
Two groups of captive macaques (M. fascicularis) were studied at the Primatological Laboratory, Kassel University, Germany. One group (D) included the animals born to high-ranking mothers, another (H) comprised those whose mothers were low-ranking. The first group was a despotic community in which conflicts occurred mainly between single individuals, and the male leader was the controlling animal. The second group was an egalitarian community split into two mutually hostile subgroups; the conflicts were less severe, and the male leader could control only his own subgroup.  相似文献   
907.
American media are the most violent in the world, and American society is now paying a high price in terms of real life violence. Research has confirmed that mass media violence contributes to aggressive behavior, fear, and desensitization of violence. Television, movies, music videos, computer/video games are pervasive media and represent important influences on children and adolescents. Portraying rewards and punishments and showing the consequences of violence are probably the two most essential contextual factors for viewers as they interpret the meaning of what they are viewing on television. Public health efforts have emphasized public education, media literacy campaign for children and parents, and an increased use of technology to prevent access to certain harmful medial materials.  相似文献   
908.
909.
BACKGROUND: Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by local or diffuse wall motion abnormalities in the right ventricle (RV), associated with recurrent ventricular tachycardia (VT) of RV origin. Brain natriuretic peptide (BNP) was first isolated from a porcine brain extract. In humans, BNP is expressed predominantly in the ventricles of failing hearts, and its expression has been observed primarily in myocytes in the interstitial fibrous area in dilated cardiomyopathy. We hypothesized that BNP is increasingly secreted from the residual myocytes within the atrophic tissue in patients with ARVD. METHODS AND RESULTS: Plasma BNP levels were measured in 17 patients with ARVD, 12 patients with idiopathic RV outflow tract tachycardia (RVOT), and 120 control subjects. We performed cardiac catheterization, RV endomyocardial biopsy, electron- beam CT, and biventricular endomyocardial mapping in the ARVD patients. There was a significant increase in plasma BNP levels in the ARVD patients compared with the RVOT patients and control subjects (61.4+/-59.6 pg/mL versus 8.3+/-5. 5 pg/mL and 9.3+/-5.8 pg/mL; P<0.0001, respectively). The plasma BNP levels had no correlation with any of the hemodynamic data, but they had a significant correlation with the RV ejection fraction (r=-0. 588, P=0.025) and with the fractionated-area scores (r=0.705, P=0. 005). Light microscopic immunohistochemistry showed strong BNP immunoreactivity in residual myocytes with fibrofatty replacement. CONCLUSIONS: These results suggest that plasma BNP levels were not increased in RVOT patients but were increased in ARVD patients, and that the increased BNP levels indicate the severity of both the RV dysfunction and the arrhythmogenic substrate.  相似文献   
910.
PURPOSE: A shortage of organs for transplantation has forced surgeons to optimize the use of marginal organs, such as kidneys with arterial disease. We present a retrospective study of the outcome of donors with renal artery disease and recipients of kidneys from living related and unrelated donors. MATERIALS AND METHODS: Kidneys with vascular abnormalities from healthy living donors were grafted into 11 recipients. These kidney transplants comprised 1.8% of those performed at our institution. The vascular abnormalities were aneurysms in 3 cases, atherosclerotic lesions in 4 and fibromuscular dysplasia in 4. After nephrectomy all abnormalities were corrected under hypothermic conditions during bench surgery except in 3 cases of ostial atherosclerotic plaque, which was left in the donors. The renal artery was anastomosed to the external iliac artery in 5 cases and to the internal iliac artery in 6. The ureter was reimplanted using an extravesical technique. RESULTS: All patients had immediate diuresis and no delayed post-transplant graft dysfunction was observed. One patient died of an unrelated cause and 3 had post-transplant graft function loss due to acute vasculopathy in 1, post-diarrhea with acute arterial thrombosis in 1 and recurrence of the hemolytic-uremic syndrome in 1. All remaining patients are well with median serum creatinine of 1.4 mg./dl. (normal 0.4 to 1.4). All donors are well and normotensive with normal renal function. CONCLUSIONS: The use of kidneys with arterial disease from living donors with unilateral disease is safe. Complete informed consent regarding the risks and benefits by donor and recipient is mandatory.  相似文献   
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