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891.
892.
The present work aimed to determine the safety parameters of two new alkamides, affinin and hexahydroaffinin, with antinociceptive activity. To predict the preliminary acute toxicity, we used the acute and subchronic toxicity (50 mg/kg, orally [po]) in Swiss Webster mice. Genotoxicity assayed via analysis of cell micronuclei of the femoral bone marrow in mice; at the same time, metabolic parameters determined from peripheral blood samples. Furthermore, to discard the neuropharmacological effects, we assessed the ambulatory activity in mice to determine the possible effects in the central nervous system. Finally, we used capsaicin as a positive control of alkamides. According to our results, hexahydroaffinin (LD50 ≥ 5,000 mg/kg, po) is significantly less noxious than affinin (LD50 = 1,442.2 mg/kg, po) or capsaicin (LD50 = 489.9 mg/kg, po). In subchronic administration, we did not observe any changes in hematological or biochemical parameters in any compound analyzed from peripheral blood samples. Finally, the data from the genotoxicity assay showed micronuclei formation in 28%, 5%, and 3% of mice in the capsaicin, affinin, and hexahydroaffinin groups, respectively. With the results obtained in the present investigation, we suggest that affinin and hexahydroaffinin are not only useful candidates for possible new drugs but also safe compounds.  相似文献   
893.
894.
Chalcones are a group of natural products with many recognized biological activities, including antiparasitic activity. Although a lot of chalcones have been synthetized and assayed against parasites, the number of structural features known to be involved in this biological property is small. Thus, in the present study, 21 chalcones were synthesized to determine the effect of substituents in the A and B rings on the activity against Leishmania braziliensis, Trypanosoma cruzi, and Plasmodium falciparum. The compounds were active against L. braziliensis in a structure-dependent manner. Only one compound was very active against T. cruzi, but none of them had a significant antiplasmodial activity. The electron-donating substituents in ring B and the hydrogen bonds at C-2′ with carbonyl affect the antiparasitic activity.  相似文献   
895.
PURPOSETo report the outcomes for 76 patients with penile cancer treated with high-dose-rate brachytherapy (HDR-BT) at a single institution.METHODSSeventy-six patients with penile cancer treated with HDR-BT in our department between October 1998 and September 2018 were analyzed. Seventy underwent interstitial HDR-BT (fractionation dose range of 3–3.5 Gy given twice a day with an interval of at least six hours between the fractions), and six underwent superficial treatment with mold applicators (fractionation dose range of 4–7 Gy given once or twice a week).RESULTSMedian follow-up was 76 months (7–204 months). In the whole group, 22/76 local failures (28.9%) were observed: 14/76 (18.4%) local recurrences and 8/76 (10.5%) cases of persistent disease. Median time to recurrence was 24 months (9–54 months). Inguinal lymph node metastases were observed in 18/76 cases (23.7%). Distant metastases occurred in 12/76 (15.8%) cases. Patients with local recurrence and persistent disease underwent salvage penectomies, except four who refused surgery and underwent a second course of interstitial HDR-BT. Five- and 10-year cause-specific survival were 85.0% and 77.8%, respectively. Local control at 5 and 10 years was 65.6%. Five- and 10-year penile preservation were 69.5% and 66.9%, respectively. There was no G3 or G4 acute toxicity. One urethral stenosis (1.3%) occurred in a patient with a T3 tumor and was treated successfully with dilatation.CONCLUSIONSHDR-BT provides good local control of penile cancer and is a good option for penis preservation therapy and in our experience achieves a penile preservation rate at 10 years of 66.9%.  相似文献   
896.
897.
CardioVascular and Interventional Radiology - Biliary complications after living donor liver transplantation (LDLT) cause severe morbidity and mortality, with biliary anastomotic stricture being...  相似文献   
898.
Journal of Neurology - Determining the cause of acute ischemic stroke is crucial for patient management, particularly for preventing future stroke. In recent years, carotid web (CW), a...  相似文献   
899.
900.
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