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71.
In this study, the ability of algae to treat a wood-based pulp and paper industry wastewater was investigated. Tests were performed in batch reactors seeded with a mixed culture of algae. Under different lighting and initial wastewater strength conditions, changes in COD, AOX and color contents of reactors were followed with time. Algae were found to remove up to 58% of COD, 84% of color and 80% of AOX from pulp and paper industry wastewaters. No remarkable differences were observed in COD and color when light intensity and wastewater strength were changed, while AOX removals were strongly affected. Algal species identification studies revealed that some green algae (Chlorella) and diatom species were dominant in the treatment. The study also showed that algae grew mixotrophically, while the main mechanism of color and organics removal from pulping effluents was partly metabolism and partly metabolic conversion of colored and chlorinated molecules to non-colored and non-chlorinated molecules. Adsorption onto algal biomass was not so effective.  相似文献   
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Background

In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery.

Methods

From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization.

Results

Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 ± 5.8% vs. 40.5 ± 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 ± 1.4 vs. 12.1 ± 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillation

Conclusion

Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore ≥ 10 and left ventricular function ≤ 30%.  相似文献   
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OBJECTIVE: To assess the diagnostic value of fine needle aspiration cytology (FNAC) in ovarian lesions. STUDY DESIGN: Sixty-two fine needle aspirations of varied ovarian masses were performed between January 2000 and February 2003. Aspiration material was obtained from fresh tissues at the time of frozen section before dissection of the specimens. The slides were evaluated by a pathologist who was blinded to the gross findings and histopathologic diagnosis. RESULTS: A total of 62.9% of cases were assessed as malignant and 30.6% as benign. Two false positive and 2 false negative cases occurred. In our series the overall sensitivity and specificity were 95.1% and 90.4%, respectively. Seven benign and 15 malignant lesions could be subclassified specifically. CONCLUSION: We studied excised specimens, but since ovarian masses are reachable by laparoscopically and ultrasonographically guided aspiration, FNAC can be used for diagnoses of these lesions. If a multidisciplinary approach can be carried out in patients with ovarian lesions, cytopathologic interpretation can provide optimum benefits.  相似文献   
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The aquaporin-4 (AQP4) water channel has been proposed to play a role in gastric acid secretion. Immunocytochemistry using anti-AQP4 antibodies showed strong AQP4 protein expression at the basolateral membrane of gastric parietal cells in wild-type (+/+) mice. AQP4 involvement in gastric acid secretion was studied using transgenic null (-/-) mice deficient in AQP4 protein. -/- Mice had grossly normal growth and appearance and showed no differences in gastric morphology by light microscopy. Gastric acid secretion was measured in anesthetized mice in which the stomach was luminally perfused (0. 3 ml/min) with 0.9% NaCl containing [(14)C]polyethylene glycol ([(14)C]PEG) as a volume marker. Collected effluent was assayed for titratable acid content and [(14)C]PEG radioactivity. After 45-min baseline perfusion, acid secretion was stimulated by pentagastrin (200 microg. kg(-1). h(-1) iv) for 1 h or histamine (0.23 mg/kg iv) + intraluminal carbachol (20 mg/l). Baseline gastric acid secretion (means +/- SE, n = 25) was 0.06 +/- 0.03 and 0.03 +/- 0.02 microeq/15 min in +/+ and -/- mice, respectively. Pentagastrin-stimulated acid secretion was 0.59 +/- 0.14 and 0.70 +/- 0.15 microeq/15 min in +/+ and -/- mice, respectively. Histamine plus carbachol-stimulated acid secretion was 7.0 +/- 1.9 and 8.0 +/- 1.8 microeq/15 min in +/+ and -/- mice, respectively. In addition, AQP4 deletion did not affect gastric fluid secretion, gastric pH, or fasting serum gastrin concentrations. These results provide direct evidence against a role of AQP4 in gastric acid secretion.  相似文献   
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The inhibition of the two transmembrane, tumor-associated isozymes of carbonic anhydrase (CA, EC 4.2.1.1) of human origin, hCA IX and XII, with a library of aromatic and heteroaromatic sulfonamides has been investigated. Most of them were sulfanilamide, homosulfanilamide, and 4-aminoethyl-benzenesulfonamide derivatives, to which tails that should induce diverse physico-chemical properties have been attached at the amino moiety, whereas several of these compounds were derived from metanilamide, benzene-1,3-disulfonamide or the 1,3,4-thiadiazole/thiadiazoline-2-sulfonamides. The tails were of the alkyl/aryl-carboxamido/sulfonamido-, ureido or thioureido type. Against hCA IX the investigated compounds showed inhibition constants in the range of 3-294 nM, whereas against hCA XII in the range of 1.9-348 nM, respectively. The best hCA IX inhibitors were ureas/thioureas incorporating 4-aminoethyl-benzenesulfonamide and metanilamide moieties. The best hCA XII inhibitors were 1,3,4-thiadiazole/thiadiazoline-2-sulfonamides incorporating 5-acylamido or 5-arylsulfonylamido moieties. These compounds also inhibited appreciably the cytosolic isozymes hCA I and II, but some selectivity for the transmembrane, tumor-associated isozymes was observed for some of them, which is an encouraging result for the design of novel therapies targeting hypoxic tumors, in which these carbonic anhydrases are highly overexpressed.  相似文献   
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The present study was designed to determine the role of topical treatment with curcumin (Cur) on burn wound healing in rats. The Wistar-albino rats were randomly allotted into one of three experimental groups: 4th, 8th and 12th day (post burn) and all groups include subgroups which Burn and Burn + Cur. Each group contains 12 animals. Burn wounds were made on the back of rat and Cur was administered topically. At the end of the study, all animals were sacrificed and the wound tissues removed for analyse to biochemical and histopathological changes. There was a significant increase in the hydroxyproline levels in the skin of the Cur groups. Cur treated wounds were found to heal much faster as indicated by improved rates of inflammatory cells, collagen deposition, angiogenesis, granulation tissue formation and epithelialization which were also confirmed by histopathological and biochemical examinations. Our data also indicate that there is a rise in the expression of proliferating cell nuclear antigen in skin tissues of Cur-treated rats in the Burn group. The results clearly substantiate the beneficial effects of the topical application of Cur in the acceleration of wound healing.  相似文献   
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