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Sana Saqrane Youness Ouahid Issam El Ghazali Brahim Oudra Lahcen Bouarab Francisca F. del Campo 《Toxicon》2009,53(7-8):786-796
The aim of the present study was to investigate the effect of exposure to a microcystin (MC)-containing extract from a cyanobacteria bloom on growth, development, mineral nutrient accumulation, and photosynthetic activity of Triticum durum, Zea mays, Pisum sativum and Lens esculenta cultivars. The MCs in the extract, identified by HPLC and/or mass spectrometry (MS) were: MC-RR, -LR, -YR, -(H4)YR, -WR, and -FR. Plant growth and development was tested along 30 exposure days. After this period, MC-extract caused a clear reduction in plant growth and productivity, as well as deleterious effects on development and Photosystem II activity, measured by Fv/Fm fluorescence. However, the chlorophyll (a + b) content hardly varied, and the accumulation of Na+, K+, Ca2+, P and N was enhanced. All the effects observed were plant species, MC concentration, and exposure-time dependent. Relative accumulation of each MC variant greatly varied among plant species and plant organ. The data obtained supports the idea that the use of surface water containing MCs for crop irrigation can affect both plant yield and quality, and secondly, that MC accumulation in edible plants might pose a potential risk for human and animal health, if the MC intake exceeded the recommended tolerable limits. 相似文献
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Maintenance of gastric pH above 6 with intravenous famotidine in patients with a bleeding duodenal ulcer 总被引:1,自引:0,他引:1
J.-C. DELCHIER I. EL AMINE F. ROUDOT-THORAVAL† L. ELOUAER-BLANC† D. LAMARQUE L. STANESCU 《Alimentary pharmacology & therapeutics》1995,9(2):191-196
Background: The secondary prevention of bleeding from ulcers may be improved if antisecretory drugs are able to maintain a 24-h gastric pH close to neutral. Aim: To evaluate the effect of intravenous famotidine at a conventional dose of 40 mg/day on 24-h intragastric pH in patients with a bleeding duodenal ulcer, and to determine the dose required to maintain gastric pH > 6 by use of a Gastrojet (MIC, Switzerland) device (a pH meter-controlled programmable pump). Methods: Twelve patients (nine men, three women), aged 24–78 years, admitted for a bleeding duodenal ulcer, were studied after active bleeding had stopped for at least 6 h. Gastric pH was recorded for two consecutive 24-h periods, each starting at 16.00 hours. The patients were fasted during these periods and received an infusion of 2.5 L of isotonic glucose. They were given famotidine, as a continuous i.v. infusion of 40 mg during one period, and at a rate determined by the Gastrojet during the other period (in a random sequence), with the aim of maintaining the gastric pH above 6. Results: The 24-h median (interquartile range) pH and the mean (± S.E.M.) percentage of the 24-h period with a gastric pH > 6 were both significantly higher during the Gastrojet period than during the continuous infusion: 6.4 (6.3–6.5) vs. 5.7 (2.7–6.4) (P < 0.01) and 74±5% vs. 44 ± 7% (P < 0.002), respectively. The mean dose of famotidine delivered by the Gastrojet was 172 mg (range: 101–200 mg). The entire available amount of famotidine (200 mg) was delivered in four of the 12 patients. The percentage of time at pH > 6 (mean ± S.E.M.) was significantly higher at night (22.00 to 07.00 hours) than during the rest of the day (88 ± 2 vs. 70 ± 6%; P < 0.005) and the mean quantity of famotidine delivered per hour was significantly lower during the night (6.3 ± 0.8 mg/h vs. 8.4 ± 0.5 mg/h; P < 0.02). Conclusion: We conclude that 40 mg of famotidine delivered as a continuous i.v. infusion is not sufficient to maintain gastric pH > 6 for 24 h in duodenal ulcer patients. Our study with the Gastrojet device shows that it may be possible to achieve this goal by using a much larger dose, preferably delivered during the day. 相似文献
86.
ADEL AL-HUNAYAN HAMDY ABDUL-HALIM ELIJAH O. KEHINDE KHALEEL AL-AWADI EHAB EL BARKY AWNI AL-ATEEQUI 《International journal of urology》2004,11(11):963-968
AIMS: To determine the incidence, mode of presentation, first line of management and composition of non-recurrent urolithiasis in Kuwait. METHODS: Consecutive patients admitted between January 1999 and December 2002 with non-recurrent urolithiasis were prospectively analyzed. RESULTS: The average annual incidence of hospital admission for non-recurrent urolithiasis in Kuwait was 43.44 per 100,000 population, representing men and women (ratio, 9:1) with a median age of 41.91 years. Of the hospital admissions for non-recurrent urolithiasis, 57.2% of cases were acute. Overall, the most predominant symptom was flank pain, while the least common symptom was acute urinary retention. Ureteroscopic stone manipulation was the most common initial treatment modality in the present series, as it was utilized in 43.3% and 37.09% for patients admitted on elective and emergency basis, respectively. Of the calculi available for chemical analysis, 91% contained calcium, 73% contained calcium oxalate, 17% contained mixed calcium and 1% contained calcium phosphate. The composition of the rest of the stones were urate in 7%, struvite in 1% and cystine in 1%. CONCLUSIONS: Urolithiasis is a common disease in the Kuwait region that mainly presents with flank pain. Ureteroscopic calculus removal is the most common modality of treatment. The majority of the calculi seen in Kuwait contained calcium. 相似文献
87.
The treatment of adult male Wistar rats with a LHRH-agonist (lutrelin Wyeth/WY 40972) resulted in severe damage of the seminiferous tubules as well as in remarkable changes of the blood vessels within 24 hours. First striking signs of alterations within the blood vessels were already found 6 hours after the injection of lutrelin: the blood vessels were almost totally filled with leucocytes. Neither the effects on the germinal epithelium nor the effects on the blood vessels were prevented by the simultaneous treatment with 3 mg testosterone propionate (TP). The treatment with indomethacin, however, clearly antagonized both events. The complete inefficiency of TP to overcome the inhibitory effects of lutrelin on the testes does argue against an androgen deficiency as the primary cause. The results obtained with indomethacin strengthen the hypothesis, that the early deleterious effects of LHRH-agonists on the germinal epithelium of the rat are primarily caused by circulatory disturbances in the testes and that prostaglandins may act as mediators. 相似文献
88.
Biological and immunological characterization of ATG and ALG 总被引:3,自引:1,他引:3
Antithymocyte globulin (ATG) and antilymphocyte globulin (ALG) are effective therapies in aplastic anemia; their mechanism of action is undefined. We assayed multiple properties of ATG and ALG to address the biological and immunological bases for differences between ATG and ALG and lot variation. In addition, we studied a lot reported to be inactive in an American clinical trial; however in retrospect, this lot appeared to be active in patients treated in Europe. Immunoprecipitation of thymocyte and lymphocyte membrane proteins with ATG and ALG showed between 14 and 18 major bands on SDS-PAGE, but the patterns for ATG and ALG were not identical. The ability of ATG and ALG to block binding of labeled monoclonal antibodies was assessed using flow cytometry and a radioimmunoassay. In general, there was more lot variation among ALGs than ATGs; however, all ALG lots were more potent blockers of binding of anti-HLA-DR and anti-Leu 1 antibodies than was ATG. Both ALG and ATG effectively blocked binding of anti-Leu 2a, anti- Leu 3a, anti-Leu 4, anti-Leu 5b, and anti-IL 2 receptor abs; neither blocked binding of anti-Leu 7. All preparations were capable of inducing T-cell blastogenesis, although there was considerable lot variation. All lots lysed 60% to 75% T cells in a rabbit complement- mediated cytotoxicity assay, with most having a plateau of activity at 5 to 10 ug/mL. Two lots of ALG, including the lot reported to be clinically inactive, showed less toxicity at suboptimal concentrations and did not plateau even at 80 ug/mL. In total, these results indicate important differences between ATG and ALG in general, more lot variation among ALGs than ATGs and only differences in cytotoxicity between an "inactive" lot of ALG and most, but not all, other active ATG and ALG preparations. 相似文献
89.
Nodular mixed lymphoma: results of a randomized trial failing to confirm prolonged disease-free survival with COPP chemotherapy 总被引:2,自引:0,他引:2
Fifty-two patients with stage III or IV nodular mixed lymphocytic- histiocytic lymphoma (NM) were entered on a prospective randomized trial comparing cyclophosphamide-prednisone (CP) to either COPP (cyclophosphamide, vincristine, procarbazine, prednisone) or BCVP (BCNU, cyclophosphamide, vincristine, prednisone). The COPP regimen utilized in this Eastern Cooperative Oncology Group (ECOG) trial was similar to the four-drug regimen C-MOPP reported by the National Cancer Institute to achieve prolonged relapse-free survival in this histology. No significant differences in complete response rates, response duration, or overall survival were noted among the three regimens. A pattern of continuous late relapse was observed for all three chemotherapy programs. Although 11 of the 18 (61%) COPP patients achieved a complete response, only 3/11 (27%) remain disease-free with a median follow-up of over 3 yr. However, two of these three long-term complete responders have died with no clinical evidence of recurrent disease. The COPP patients received 84% of the calculated ideal doses of cyclophosphamide and 78% of the ideal dosage of procarbazine. Grade 3-4 hematologic toxicity was noted in 22% of the COPP group, 36% with BCVP, and 0% for the CP patients. We were unable to confirm the ability of COPP to achieve durable complete remissions in NM lymphoma. The cyclophosphamide-prednisone combination was equally effective when compared with COPP and BCVP, but produced minimal toxicity. 相似文献
90.
Medhat A. F. SHALABY Suliman M. AL HUMAYED Ahmed M. DEWEDAR Tunis A. EL‐SAEED 《International journal of rheumatic diseases》2008,11(3):311-314
Rosai‐Dorfman disease (RDD) is a rare benign reactive lymphoproliferative disorder characterised by a histopathological pattern with sinus histiocytosis and hemophagocytosis. It usually presents with fever, elevated erythrocyte sedimentation rate, cervical lymphadenopathy, other lymph node and extra‐nodal site involvement. We present the case of a 25‐year‐old female patient with polyarthritis mimicking rheumatoid arthritis (RA). When the para‐aortic lymph node was biopsied, it showed extensive histiocytic proliferation; some clusters of plasma cells, lymphocytes and rare multinucleated cells were seen, suggesting a diagnosis of RDD. There is nothing in the literature regarding the polyarthritic presentation of the disease. To the best of our knowledge, our patient is the first case of RDD presenting with a clinical picture mimicking atypical seronegative RA. 相似文献