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The reaction of 5-amino-3-(arylamino)-1H-pyrazole-4-carboxamides 1a,b with acetylacetone 2 and arylidenemalononitriles 5a–c yielded the pyrazolo[1,5-a]-pyrimidine derivatives 4a,b and 7a–f respectively. On the other hand, Schiff bases 9a,b and 12a–j were obtained upon treatment of carboxamides 1a,b with isatin 8 and some selected aldehydes 11a–e. The newly synthesized compounds were characterized by analytical and spectroscopic data. Representative examples of the synthesized products 4a,b, 7e, 7f, 9b, 12b–f, 12h, and 12j were screened for their in vitro antitumor activities against different human cancer cell lines and the structure-activity relationship (SAR) was discussed.  相似文献   
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A central venous catheter was inserted in a 37-year-old man. During placement the catheter took a route to the left side of the heart. On CT it appeared the catheter was placed in a persisting left V. cava superior.  相似文献   
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COVID-19 pandemic is spreading around the world becoming thus a serious concern for health, economic and social systems worldwide. In such situation, predicting as accurately as possible the future dynamics of the virus is a challenging problem for scientists and decision-makers. In this paper, four phenomenological epidemic models as well as Suspected-Infected-Recovered (SIR) model are investigated for predicting the cumulative number of infected cases in Saudi Arabia in addition to the probable end-date of the outbreak. The prediction problem is formulated as an optimization framework and solved using a Particle Swarm Optimization (PSO) algorithm. The Generalized Richards Model (GRM) has been found to be the best one in achieving two objectives: first, fitting the collected data (covering 223 days between March 2nd and October 10, 2020) with the lowest mean absolute percentage error (MAPE = 3.2889%), the highest coefficient of determination (R2 = 0.9953) and the lowest root mean squared error (RMSE = 8827); and second, predicting a probable end date found to be around the end of December 2020 with a projected number of 378,299 at the end of the outbreak. The obtained results may help the decision-makers to take suitable decisions related to the pandemic mitigation and containment and provide clear understanding of the virus dynamics in Saudi Arabia.  相似文献   
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We reported a case of patient born in 1967 who has been operated on in 1987 on three years after the beginning of ulcerative colitis which became severe and resistant to the medical treatment. A total colectomy with an ileo-rectal anastomosis had been performed. The pathological diagnosis carried of the specimen was Ulcerative colitis Then a proctectomy, followed by ileo-anal anastomosis, was performed in 1993. After several episodes of pochitis and the appearance of intestinal lesions upstream the ileal pocket, the retained diagnosis was Crohn's colitis. Eight years after the ileo-anal anastomosis, the patient developed an adenocarcinoma in the ileal pocket. He has been operated on in 2002 and he had abdominoperineal resection, radiotherapy and chemotherapy. Re died in January 2003. The death was related to the recurrence of malignancy. Endoscopic controls with biopsies are mandatory doing to follow up dysplasia predictive of degeneration.  相似文献   
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AIMS: The purpose of this study was to assess the safety, efficacy, and long-term results (up to 18 years) of mitral balloon valvuloplasty (MBV) in children in comparison to adults. METHODS: 57 children age < or = 18 years (group A) and 474 adult patients (group B) who underwent successful MBV and were followed up for a mean 8.5 +/- 4.8 (range 1.5-18) years were analyzed. RESULTS: Patients in group A had a lower mitral echocardiographic score (echo score), 7.6 +/- 1.3 vs. 8.1 +/- 1 (P = 0.0005); smaller Doppler mitral valve area (MVA), 0.82 +/- 0.16 cm(2) vs. 0.92 +/- 0.17 cm(2) (P < 0.0001); and higher mitral valve gradient, 15.2 +/- 2.3 mmHg vs. 14.3 +/- 2.1 mmHg (P = 0.0003), than group B. Immediately after MBV, group A had larger MVA whether measured by catheter, 1.99 +/- 0.57 cm(2) vs. 1.8 +/- 0.52 cm(2) (P < 0.001), or by Doppler, 2.0 +/- 0.27 cm(2) vs. 1.97 +/- 0.28 cm(2) (P < 0.01), and similar complication rates, compared to group B. After a mean follow-up of 8.5 +/- 4.8 (range 1.5-18 years), restenosis in group A was 26% vs. 31% for group B (P = 0.41). Echo score > 8 (P = 0.046) was a predictor of restenosis in children and echo score > 8 (P < 0.0001) and previous surgery (P = 0.043) were predictors of restenosis in adults. Actuarial freedom from restenosis at 10, 15, and 18 years for groups A and B were 78%+/- 7%, 64%+/- 9%, and 18%+/- 14% and 77%+/- 2%, 43%+/- 4%, and 17%+/- 4%, respectively (P = 0.26). Event-free survival rates at 10, 15, and 18 years were 87%+/- 6%, 62%+/- 1%, and 20%+/- 2% versus 87%+/- 1%, 51%+/- 4%, and 20%+/- 5% for groups A and B, respectively (P = 0.51). Postprocedure MVA < 2.0 cm(2) (P = 0.043) and previous surgery (P = 0.03) were identified as predictors of events in children. Echo score > 8 (P < 0.0001) and prevalvuloplasty AF (P = 0.03) were identified as predictors of events in adults. CONCLUSION: MBV is safe and effective in children with rheumatic MS. It provides better immediate results than in adults and excellent long-term results that are comparable to those seen in adults.  相似文献   
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