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991.
992.
Two new metabolites 5alphaH,7alphaH-eudesman-4alpha,6alpha,11,12-tetraol (1) and 1beta,15-dihydroxy-5alphaH,7alphaH-eudesma-3,11(13)-dien-12,6alpha-olide ( 2) have been isolated from the methanolic extract of Laurus nobilis L. leaves. Their structures were determined through analysis of their one- and two-dimensional NMR spectral data ((1)H- and (13)C-NMR, DEPT, COSY, HMQC, HMBC and ROESY). The relative stereochemistry is proposed on the basis of combined J-based configuration analysis and ROESY data. In addition, three known sesquiterpene lactones santamarine (3), reynosin (4) and costunolide (5) along with blumenol C (6) were isolated and identified by spectral means. The isolated compounds 1 - 6 were found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophages. The most active compound 2 potently inhibited NO (2)(-) release with an IC (50) value of 0.8 microM.  相似文献   
993.
Rationale Many behavioral effects of delta-9-tetrahydrocannabinol (THC), including its discriminative-stimulus effects, are modulated by endogenous opioid systems.Objective To investigate opioid receptor subtypes involved in the discriminative effects of THC.Methods Rats trained to discriminate 3 mg/kg i.p. of THC from vehicle using a two-lever operant drug-discrimination procedure, were tested with compounds that bind preferentially or selectively to either mu-, delta- or kappa-opioid receptors.Results The preferential mu-opioid receptor agonist heroin (0.3–1.0 mg/kg, i.p.), the selective delta-opioid receptor agonist SNC-80 (1–10 mg/kg, i.p.) and the selective kappa-opioid receptor agonist U50488 (1–10 mg/kg, i.p.) did not produce generalization to the discriminative effects of THC when given alone. However, heroin, but not SNC-80 or U50488, significantly shifted the dose–response curve for THC discrimination to the left. Also, the preferential mu-opioid receptor antagonist naltrexone (0.1–1 mg/kg, i.p.), the selective delta-opioid receptor antagonist, naltrindole (1–10 mg/kg, i.p.) and the kappa-opioid receptor antagonist nor-binaltorphimine (n-BNI, 5 mg/kg, s.c.), did not significantly reduce the discriminative effects of the training dose of THC. However, naltrexone, but not naltrindole or n-BNI, significantly shifted the dose–response curve for THC discrimination to the right. Finally, naltrexone, but not naltrindole or n-BNI, blocked the leftward shift in the dose–response curve for THC discrimination produced by heroin.Conclusions mu- but not delta- or kappa-opioid receptors are involved in the discriminative effects of THC. Given the role that mu-opioid receptors play in THCs rewarding effects, the present findings suggest that discriminative-stimulus effects and rewarding effects of THC involve similar neural mechanisms.  相似文献   
994.
BACKGROUND: Current treatment regimens for Waldenstrom macroglobulinemia (WM) are based on the use of oral alkylating agents. Recently, however, other more costly agents have been proposed for the treatment of WM. In the current study, the authors report on results obtained using oral melphalan, cyclophosphamide, and prednisone (MCP) to treat 72 patients with WM, and they compare these results (and the associated costs) with those observed using more aggressive protocols. METHODS: Between July 1973 and April 2002, the authors documented overexpression of the immunoglobulin M paraprotein in 317 consecutive patients. Of these, 100 had newly diagnosed WM, and the 72 who were symptomatic were treated using the MCP protocol. Response rate, overall survival (OS), response duration, freedom from progression (FFP), event-free survival (EFS) duration, toxicity, and cost per course in Euro and U.S. dollars were evaluated for patients receiving this regimen. RESULTS: Seventy-one of 72 patients (99%) were evaluable. Of these patients, 55 (77%) achieved a response; 7 others (10%) experienced disease stabilization, and the remaining 9 (13%) experienced disease progression. After a median follow-up of 72 months (range, 3-195 months), the median durations of EFS, FFP, response, and OS were 47, 55, 64, and 66 months, respectively. No World Health Organization Grade III or IV toxicities were observed, and side effects were limited to transient nausea, emesis, and mild neutropenia. The cost per course of the MCP regimen was $16, similar to that of standard protocols involving chlorambucil and much less than that of more aggressive protocols (price range, $91-11091) proposed for the treatment of WM. CONCLUSIONS: Like chlorambucil-based protocols, the MCP regimen is a cost-effective and safe option for the treatment of patients with WM. Furthermore, the results obtained do not appear to be inferior to those yielded by more expensive, aggressive, and toxic intravenous protocols.  相似文献   
995.
Rigacci L  Carrai V  Nassi L  Alterini R  Longo G  Bernardi F  Bosi A 《Cancer》2005,103(5):970-977
BACKGROUND: The standard treatment for patients with aggressive non-Hodgkin lymphoma (NHL) is cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Since 1989, the authors have used a new chemotherapy regimen with combined carmustine, doxorubicin, etoposide, vincristine, and cyclophosphamide plus mitoxantrone, cytarabine and methotrexate with citrovorum factor called BAVEC-MiMA. The objective of the current study was to explore, after a long follow-up period, the impact of this third-generation regimen for the treatment of aggressive NHL. METHODS: One hundred and one consecutive patients (median age, 41 years) with either B-cell (n=94 patients) or non-B-cell (n=7 patients), aggressive lymphoma were diagnosed and treated between 1989 and 1999 with the BAVEC-MiMA regimen. RESULTS: The complete response rate was 74%, and the overall response rate was 89%. Eleven patients with refractory disease died rapidly after a median period of 5 months. The major toxicity was Grade 4 neutropenia (according to World Health Organization criteria), which was observed in 15 patients (15%). There were four toxicity-related deaths. The overall survival rate was 63% at 9 years. In multivariate analysis, factors that were associated with advantage in overall survival were response to induction therapy, bulky disease, and high score on the International Prognostic Index (IPI). The disease-free survival rate was 77% at 9 years. In multivariate analysis, the IPI was the most important variable for the definition of disease-free survival. CONCLUSIONS: The BAVEC-MiMA regimen was feasible on an outpatient basis, it was tolerated well, and it showed a low toxicity-related mortality. The long follow-up in patients with NHL, which is a rapidly fatal disease, led the authors to observe that, with this regimen, a cure was obtained in > 50% of patients who had low-risk or low-to-intermediate-risk, aggressive NHL.  相似文献   
996.
BACKGROUND: Second primary tumors (SPT) constitute a major threat to the survival of patients with laryngeal carcinoma. However, to the authors' knowledge little is known regarding the risk factors for developing SPTs or about the strategy to be followed to avoid them. METHODS: Eight hundred seventy-six male patients with laryngeal/hypopharyngeal carcinoma enrolled in a population-based, case-control study in 5 centers from South Europe during 1979-1982 were followed up to ascertain the occurrence of SPTs. Standardized incidence ratios were calculated to estimate the risk of SPT occurring in the cohort. Cox proportional hazard models were fitted to estimate the hazard ratio for development of SPTs in relation to use of tobacco smoking, alcohol consumption, and dietary habits before the first primary tumor. RESULTS: One hundred forty-five patients developed an SPT with an annual average rate of 2.1%. An excess risk of developing an SPT of the tongue, mouth, esophagus, and lung was observed. No elevated risks of SPTs were observed in other organs. Alcohol consumption strongly increased the risk of developing an SPT of the upper aerodigestive tract (UADT). Heavy cumulative cigarette smoking increased the risk of developing a lung SPT. A protective effect of high intake of citrus fruit was noticed for SPT in the lung, whereas high butter intake was associated with an increased risk for SPT of the UADT. CONCLUSIONS: Continuous medical surveillance was essential in the UADT and lung to reduce the risk from an SPT after initial laryngeal/hypopahryngeal carcinoma. Alcohol consumption before the first primary tumor was a risk factor for SPT of the UADT. The study suggested a protective role of citrus fruits in the development of a lung SPT.  相似文献   
997.
BACKGROUND: Patients with unresectable biliary tract carcinomas have a very poor prognosis. To improve the efficacy and tolerance of the ECF regimen (epirubicin at a dose of 50 mg/m2, cisplatin at a dose of 60 mg/m2, and 5-fluorouracil [5-FU] at a dose of 200 mg/m2 per day by continuous infusion), the authors designed a novel approach that combined locoregional and systemic chemotherapy with the same agents at the same dosages. METHODS: Thirty consecutive patients with advanced or metastatic biliary tumors were treated with epirubicin at a dose of 50 mg/m2 and cisplatin at a dose of 60 mg/m2 administered as a bolus in the hepatic artery on Day 1, combined with systemic continuous infusion of 5-FU at a dose of 200 mg/m2 per day, from Day 1 to Day 14, every 3 weeks. RESULTS: Tumor sites were the intrahepatic bile ducts in 25 patients and the gallbladder in 5 patients. The overall response rate was 40% (12 of 30 patients), including 1 complete response and 11 partial responses. Stable disease was observed in 12 of 30 patients (40%) and progressive disease in 6 of 30 patients (20%). The median progression-free and overall survival periods were 7.1 and 13.2 months, respectively, and the 1-year and 2-year survival rates were 54% and 20%, respectively. Performance status improved in 9 of 30 patients (30%) and a weight gain of > 7% was observed in 4 of 30 patients (13%). The treatment was well tolerated with minimal hematologic toxicity. The major clinical problem was the deep venous thrombosis related to the central venous catheter, which occurred in 5 patients (17%). CONCLUSIONS: This novel combined locoregional and systemic chemotherapeutic regimen was found to be active and safe for patients with advanced biliary tract carcinoma.  相似文献   
998.
Exposure to PCBs and p,p'-DDE and human sperm chromatin integrity   总被引:2,自引:0,他引:2  
Persistent organochlorine pollutants (POPs) such as polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (p,p'-DDE), the major metabolite of dichlorodiphenyltrichloroethane (DDT), are stable lipophilic compounds widely found in the environment and in the general population. They can enter the food chain, and their negative impact on male reproduction is currently under active scrutiny. To explore the hypothesis that environmental exposure to these compounds is associated with altered sperm chromatin structure integrity in human sperm, we conducted a study of 176 Swedish fishermen (with low and high consumption of fatty fish, a very important exposure source of POPs). We determined serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and p,p'-DDE, and we used the sperm chromatin structure assay (SCSA) to assess sperm DNA/chromatin integrity. When CB-153 serum levels (individual dose range, 39-1,460 ng/g lipid) were categorized into equally sized quintiles, we found an association with the DNA fragmentation index (%DFI). A significantly lower %DFI was found in the lowest CB-153 quintile (< 113 ng/g lipid) compared with the other quintiles; there was a similar tendency, although not statistically significant, between %DFI and p,p'-DDE. These results suggest that POP exposure may have a slight negative impact on human sperm chromatin integrity.  相似文献   
999.
Chromosomal aberrations in lymphocytes of healthy subjects and risk of cancer   总被引:10,自引:0,他引:10  
There is evidence that increased frequency of chromosomal aberration (CA) in peripheral blood lymphocytes is a predictor of cancer, but further data are needed to better characterize CA as marker of cancer risk. From the archives of 15 laboratories we gathered cytogenetic records of 11,834 subjects who were free of cancer at the moment of blood drawing and who underwent cytogenetic examination for preventive purposes in the Czech Republic during 1975-2000. We linked these records to the national cancer registry, revealing a total of 485 cancer cases. Subjects were classified according to the percentiles of CA distribution within each laboratory as low (0-33rd percentile), medium (34-66th percentile), and high (66-100th percentile). Subjects were further classified by occupational exposure and by subclass of CA. We found a significant association between the overall cancer incidence and the presence of chromosome-type aberrations [relative risk (RR) for high vs. low CA level = 1.24; 95% confidence interval (CI), 1.03-1.50] but not chromatid-type aberrations. Stomach cancer showed a strong association with frequency of total CA (RR = 7.79; 95% CI, 1.01-60.0). The predictivity of CA observed in subjects exposed to various classes of carcinogens did not significantly differ from the group of nonexposed subjects. This study contributes to validation of CA as a predictive marker of cancer risk, in particular, of stomach cancer; the association between CA frequency and cancer risk might be limited to chromosome-type aberrations.  相似文献   
1000.
This historic-sociological study aims to analyze the daily challenges faced by army nurses in the Theater of Operations during the Second World War in Italy. The primary sources of investigation consist of three photographs taken during that period as well as testimonies by nine nurses, while literature on the subject is used as a secondary source. The discussion is supported by Pierre Bourdieu's concepts. The results show that these nurses faced the challenges of daily life at war and managed to adapt themselves to the adversities of the camping sites and wards. We infer that their daily life in this scenario not only made them overcome barriers, but also provided them with an opportunity to get to know new cultures and technologies.  相似文献   
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