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991.
992.
The Miconia genus, a plant widely used for medicine, occurs in tropical America and its extracts and isolated compounds have demonstrated antibiotic, antitumoral, analgesic and antimalarial activities. However, no study concerning its genotoxicity has been conducted and it is necessary to determine its potential mutagenic effects to develop products and chemicals from these extracts. This study assessed the cytotoxicity, mutagenicity and the protective effects of methanolic extracts from Miconia species on Chinese hamster lung fibroblast cell cultures (V79). The cytotoxicity was evaluated using a clonogenic assay. Cultures exposed to the extract of Miconia albicans up to a concentration of 30 μg/mL, M. cabucu up to 40 μg/mL, M. albicans up to 40 μg/mL and M. stenostachya up to 60 μg/mL exhibited a cytotoxic effect on the cells. The clonogenic assay used three non-cytotoxic concentrations (5, 10 and 20 μg/mL) to evaluate mutagenicity and antimutagenicity of the extracts. Cultures were treated with these three extract concentrations (mutagenicity test) or the extract associated with doxorubicin (DXR) (antimutagenicity test) in three protocols (pre-, simultaneous and post-treatments). Distilled water and DXR were used as negative and positive controls, respectively. In the micronucleus (MN) test, a significant reduction was observed in MN frequency in cultures treated with DXR and extracts compared to those receiving only DXR; a significant reduction was also observed for the presence of mutagenicity in all treatments. This study confirmed the safe use of Miconia extracts at the concentrations tested and reinforced the therapeutic properties previously described for Miconia species by showing their protective effects on doxorubicin-induced mutagenicity.  相似文献   
993.
We report on a patient with rare anaphylaxis after ingestion of raw bell pepper. A complex cluster of sensitization including grass and birch pointed out a possible pollen-associated food allergy. We suggest that the severe reaction is due to cross-reactivity towards Bet v 1. Western blot showed binding of the patient’s serum to an 11 kDa protein, which has not been described yet and might be a new allergenic structure of the bell pepper plant or a fragment of the Bet v 1-homologous bell pepper protein.  相似文献   
994.
BACKGROUND: A case of basal cell carcinoma (BCC) developing in the repair scar of a cleft lip is presented. OBJECTIVE: Primary BCCs arising in surgical scars are very rare and no known reported cases exist of a BCC developing in a surgically repaired cleft lip scar. METHODS: A 69-year-old white man presented with a 5 mm primary BCC on his upper lip at the site of his cleft lip repair scar. The diagnosis was made by a tangential biopsy that showed an ulcerated BCC. RESULTS: Review of the medical literature indicates that a scar may be an independent risk factor for developing BCC. CONCLUSION: BCC may rarely arise in a cleft lip repair scar.  相似文献   
995.
Members of the Nod-like receptor (NLR) family recognize intracellular pathogens and recruit a variety of effector molecules, including pro-caspases and kinases, which in turn are implicated in cytokine processing and NF-κB activation.  相似文献   
996.
Circulatory arrest in accidental hypothermia is a special challenge for the emergency physician, starting with the difficulty of diagnosis because of bradycardia and hypotonia. Extracorporal circulation is the standard method of rewarming in deep hypothermia with circulatory arrest. When not available, conservative rewarming with forced air, warmed infusions and ventilator gas, dialysis, peritoneal and pleural lavage are alternatives that have been successful. These conservative methods are also effective in cases of hypothermia with sustained perfusion although there is no accordance about the optimal method of rewarming these patients. In hospital the decision whom to take on extracorporal circulation or to terminate resuscitative efforts must remain individualized. Elevated serum potassium levels and prolonged activated clotted time indicate patients in whom deleterious hypoxia has preceded the protective effects of hypothermia. A submersion time of victims in icewater up to 66 min has been survived. In asystolic avalanche victims, a time of >45 min in absence of an air pocket is a good triage criteria for preclinical declaration of death.  相似文献   
997.
998.
999.
PURPOSE: To assess the diagnostic accuracy of mammography, ultrasound, and magnetic resonance imaging (MRI) of the breast in the surveillance of women at high risk for breast cancer. EXPERIMENTAL DESIGN: In this prospective comparison study, women at high risk for breast cancer were offered annual surveillance examinations, consisting of mammography, ultrasound, and MRI, at a single tertiary care breast center. The sensitivity and specificity of each modality was based on the histopathologic evaluation of suspicious findings from all modalities plus the detected interval cancers. RESULTS: Three hundred and twenty-seven women underwent 672 complete imaging rounds. Of a total of 28 detected cancers, 14 were detected by mammography, 12 by ultrasound, and 24 by MRI, which resulted in sensitivities of 50%, 42.9%, and 85.7%, respectively (P < 0.01). MRI detected not only significantly more invasive but also significantly more preinvasive cancers (ductal carcinoma in situ). Mammography, ultrasound, and MRI led to 25, 26, and 101 false-positive findings, which resulted in specificities of 98%, 98%, and 92%, respectively (P < 0.05). Thirty-five (35%) of these false-positive findings were atypical ductal hyperplasias, lesions considered to be of premalignant character. Nine (26%) of those were detected by mammography, 2 (6%) with ultrasound, and 32 (91%) with MRI (P < 0.01). CONCLUSION: Our results show that MRI of the breast improves the detection of invasive cancers, preinvasive cancers, and premalignant lesions in a high-risk population and should therefore become an integral part of breast cancer surveillance in these patients.  相似文献   
1000.
BACKGROUND: Combinations of gemcitabine-oxaliplatin, gemcitabine-5-fluorouracil (5-FU) and 5-FU-oxaliplatin have synergistic activity and nonoverlapping adverse effect profiles. This trial assessed efficacy and safety of the triple combination gemcitabine-oxaliplatin and infusional 5-FU in patients with locally advanced (n=11) or metastatic (n=32) pancreatic adenocarcinoma. PATIENTS AND METHODS: A total of 43 eligible patients were treated with intravenous infusions of gemcitabine (900 mg/m2 over 30 min), followed by oxaliplatin (65 mg/m2 over 2 h) and 5-FU (1500 mg/m2 over 24 h) on days 1 and 8 of a 21-day cycle. RESULTS: Among all 43 patients, the tumor response rate was 19% [95% confidence interval 7% to 30%]. Nine patients were nonassessable for response because they did not complete the first two cycles of chemotherapy due to rapid disease progression, early death or treatment refusal. One patient was lost to follow-up. Median time to progression and overall survival were 5.7 and 7.5 months. Principal grade III/IV toxic effects were leucopenia in 11 (2%), thrombocytopenia in 13 (2%), nausea in 13 (0%), anorexia 16 (7%) and sensory neuropathy in 18 (0%) of patients. Unexpected cardiotoxicity was observed in this trial. CONCLUSION: Response rates and survival of the three-drug combination compare favorably with single-agent gemcitabine, but do not exceed results for doublets.  相似文献   
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