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1.
The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO2/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency.  相似文献   
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Purpose  Congenital clasped thumb is a deformity that is associated with heterogeneous congenital anomalies and it has been addressed in many congenital syndromes. The aim of this study was to diagnose and evaluate cases of clasped thumb as regards the associated congenital anomalies and syndromes, and evaluation of the results of treatment of such cases. Methods  A prospective study on 40 patients with 73 clasped thumbs was done. All the patients’ data regarding their personal, family, pregnancy and developmental histories were recorded. All the patients were exposed to thorough clinical and radiological examination and genetic assessment. The cases were classified using the Tsuyuguchi et al. (J Hand Surg [Am] 10:613–618, 1985) classification into three types. Conservative treatment was adopted in ten hands, and surgical treatment was performed for 28 hands in 17 patients, with an average follow-up of 26 months. Results  Positive consanguinity was recorded in 57.5% of cases. Associated anomalies were recorded in 77.5% of cases. Type I was the most common one, followed by type III and then type II. Conservative treatment is effective in type I cases when presented early, and all patients were satisfied with the results of surgical treatment. Conclusions  We reported associated anomalies which are to our knowledge have not mentioned before in the literature which include; congenital blindness, radial deviation of the index finger and ventricular septal defect. We found that 68% of the patients had associated syndromes, and this has not been mentioned before. In this study, we found that there were no difference between type II and type III clasped thumb as regards the pathological findings, severity, the operative procedures, the treatment protocol and the operative results. Properly planned treatment gives satisfactory results.  相似文献   
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The clinical, biochemical and pathological features of 31 patients with thyroid carcinoma managed at Hospital Universiti Sains Málaysia, Kubang Kerian from 1985 to 1989 were analyzed. There were 25 females and 6 males. The types of carcinoma were: papillary-17 cases; follicular-10 cases; medullary-2 cases and anaplastic-2 cases. For papillary carcinoma the mean age of the patients was 52.9 years. For follicular carcinoma the mean age was 48.3 years, for medullary carcinoma, 48.5 years and for anaplastic, 74.5 years. All patients had pre-existing goitre except for 2 and most presented with advanced disease. The mean duration of symptoms for papillary carcinoma was 3.7 years, follicular carcinoma 1.6 years, medullary carcinoma 13.5 years and anaplastic carcinoma 6 months. 12 patients presented with goitre of increasing size; 9 had compression symptoms; 4 presented with cervical lymph node enlargement and 6 presented with bony pains of whom 2 had paraplegia. None of the patients were ever thyrotoxic or hypothyroid. Treatment in general was unsatisfactory because of patients' non-acceptance of surgery and/or radioactive iodine.  相似文献   
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One case of a cervical osteoid osteoma is presented and compared with infrequent similar cases from the literature. The authors recall the diagnosis difficulties, facing a long standing not explained neck pain due to poor neurological and current radiological informations. The interest of the bone scintigraphy, CT scan and M.R.I. are emphasized. Like in other cases, the pain disappeared after surgical removal of the tumor. The eventually associated scoliosis often rectify too.  相似文献   
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BACKGROUND: Hypertension is a potential risk factor for allograft coronary vasculopathy. We evaluated the efficacy of angiotensin-converting enzyme (ACE) inhibitors and calcium antagonists, and their combined use, on the development of coronary vasculopathy in hypertensive heart transplant recipients. METHODS: Eighty-two heart transplant recipients underwent serial intravascular ultrasound (IVUS) analysis at baseline (within 1 month) and at 1 year after transplantation and were evaluated for the development of coronary vasculopathy. Patients were divided into 4 groups. Nineteen normotensive recipients received no treatment, control (Group A). Hypertensive patients were treated with either ACE inhibitors (Group B, n = 37), calcium antagonists (Group C, n = 16), or both (Group D, n = 10). RESULTS: We found a significant reduction in IVUS indices of coronary vasculopathy in heart transplant recipients who used a combination of an ACE inhibitor and a calcium antagonist compared with recipients who used either drug alone (p < 0.05). This synergistic efficacy was independent of the baseline indices evaluated in a multivariate regression analysis model and was noted despite comparable mean arterial pressure among the 3 hypertensive groups at 1 year, thus suggesting the presence of a synergistic anti-proliferative effect beyond the anti-hypertensive efficacy. CONCLUSIONS: The combined use of an ACE inhibitor and a calcium antagonist is more effective than the individual use of either drug alone on the development of coronary vasculopathy in cardiac transplant recipients. Large randomized clinical trials are warranted to evaluate such a synergistic efficacy.  相似文献   
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BACKGROUND: A cascade of inflammatory reactions characterize acute vascular rejection after heart transplantation. This study was undertaken to test the hypothesis that acute vascular rejection is associated with up-regulation of vitronectin receptor (alphavbeta3), increased expression of tissue factor, and activation of the extracellular matrix metalloproteinase induction system. METHODS: Acute vascular rejection developed in 14 heart transplant recipients within 2 weeks of transplantation, confirmed by immunofluorescence (AVR group). We compared these patients with 10 transplant recipients who had no evidence of acute vascular rejection or peritransplant ischemic injury (control group). We evaluated endomyocardial biopsy specimens for alphavbeta3, tissue factor, and extracellular matrix metalloproteinase inducer (EMMPRIN). RESULTS: Compared with the control group, the AVR group demonstrated evidence of significantly increased expression of alphavbeta3 (1.9-fold, p < 0.001), tissue factor (1.8-fold, p < 0.001), and EMMPRIN (1.5-fold, p < 0.001). All patients in the AVR group received plasmapheresis; 11 of 14 patients had evidence of ischemic necrosis on biopsy specimens, and 3 of 14 patients experienced hemodynamic compromise and graft dysfunction and died within 3 weeks of transplant. Another patient died at 10 months after transplant. CONCLUSIONS: Acute vascular rejection is associated with up-regulation of alphavbeta3, tissue factor, and activation of the matrix metalloproteinase induction system, which may contribute to the lethal morbidity associated with this disease.  相似文献   
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Our objectives were to devise a cytologic grading system and determine whether it would predict survival of patients with solid-type pancreatic adenocarcinoma. We evaluated 116 consecutive patients from July 2000 to November 2002; they were followed up until September 2003. We scored the following features on rapid Romanowsky-stained endoscopic ultrasound-guided fine-needle aspiration smears: cell group architecture, single cells, nuclear grade, mucus, bizarre cells, and necrosis. A cytologic grade (low vs high) was assigned. The Kaplan-Meier estimate of 6-month survival was 76% (SE, 7%) for patients with low-grade tumors vs 50% (SE, 6%) for patients with high-grade carcinoma. The median survival for patients with low-grade vs high-grade tumors was 1 year vs 6 months, respectively (chi2 = 4.45; P = .035). Cox proportional hazards regression showed tumor stage, cancer-specific treatment, and cytologic grade to be independent predictors of survival (P = .001). No other factors (age, mass location, placement of stent, presence of concomitant chronic pancreatitis, race, sex) predicted survival. We devised a grading system that independently predicted survival in patients with pancreatic adenocarcinoma.  相似文献   
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