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1.
This study sought to assess sediment contamination by trace metals (cadmium, chromium, cobalt, copper, manganese, nickel, lead and zinc), to localize contaminated sites and to identify environmental risk for aquatic organisms in Wadis of Kebir Rhumel basin in the Northeast of Algeria. Water and surficial sediments (0-5 cm) were sampled in winter, spring, summer and autumn from 37 sites along permanent Wadis of the Kebir Rhumel basin. Sediment trace metal contents were measured by Flame Atomic Absorption Spectroscopy. Trace metals median concentrations in sediments followed a decreasing order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Extreme values (dry weights) of the trace metals are as follows: 0.6-3.4 microg/g for Cd, 10-216 microg/g for Cr, 9-446 microg/g for Cu, 3-20 microg/g for Co, 105-576 microg/g for Mn, 10-46 microg/g for Ni, 11-167 microg/g for Pb, and 38-641 microg/g for Zn. According to world natural concentrations, all sediments collected were considered as contaminated by one or more elements. Comparing measured concentrations with American guidelines (Threshold Effect Level: TEL and Probable Effect Level: PEL) showed that biological effects could be occasionally observed for cadmium, chromium, lead and nickel levels but frequently observed for copper and zinc levels. Sediment quality was shown to be excellent for cobalt and manganese but medium to bad for cadmium, chromium, copper, lead, nickel and zinc regardless of sites.  相似文献   
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The objectives of this study are to use different approaches to assess the current pollution status in the wadis of the Kebir Rhumel basin. First, sediment trace metal contents were measured by flame atomic absorption spectroscopy. Then, sediment quality was assessed on the basis of contamination assessment indexes such as: Geoaccumulation Index (Igeo), Contamination factor (C(f)), Contamination degree (C(d)), Sediment Pollution Index (SPI) and SEQ guidelines (Consensus Sediment Quality Guidelines). In addition, several toxicity tests (Daphnia magna mobility inhibition acute test-48 h, Aliivibrio fischeri luminescence inhibition acute test - 15/30 mn and Pseudokirchneriella subcapitata growth inhibition chronic test - 72 h) were conducted to assess sediment pore water ecotoxicity. Trace metal concentrations followed the order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Indexes used indicate varying degrees of sediment quality. Igeo, C(f), C(d) and SPI reveal a polymetallic contamination dominated by two or more elements in which Cd, Cu and Pb are of greatest concern. SEQ guidelines showed that biological effects on fauna would likely be observed occasionally and/or frequently for Cd, Cr, Cu, Pb and Zn contents. Test organisms exposed to sediment pore water showed that the algal P. subcapitata test was more sensitive than the D. magna and A. fischeri tests. Hence, algal growth inhibition proved to be the most sensitive response to contaminants present in sediment extracts but a significant relationship with trace metal contents was not demonstrated.  相似文献   
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OBJECTIVE: To determine the independent biologic effects of 17 alpha-dihydroequilin sulfate. DESIGN: Prospective randomized study. SETTING: University of Southern California Medical Center. PATIENTS(S): Twenty-one postmenopausal women, mean age 50 +/- 2 (+/-SEM) years, and mean body mass index 27 +/- 2. INTERVENTION(S): Women were randomized to receive daily oral doses of either 1.25 mg of estrone sulfate (E1S), 0.2 mg of 17 alpha-dihydroequilin sulfate, or a combination. Three blood and urine samples were obtained before and after 30 and 90 days of treatment. RESULT(S): After 30 and 90 days of treatment, E1S alone increased sex hormone-binding globulin (SHBG) levels significantly, 19.7% +/- 6.0% and 61.3% +/- 13.0%, whereas 17 alpha-dihydroequilin sulfate reduced SHBG levels, 20.8% +/- 68% and 12.4% +/- 7.5%, respectively. Nevertheless, the combination of E1S and 17 alpha-dihydroequilin sulfate significantly increased SHBG levels, 103% +/- 27.9% and 98.2% +/- 19.1%, compared with baseline at 30 and 90 days. Fewer changes were evident with corticosteroid-binding globulin (CBG). After 90 days of treatment, CBG levels significantly increased 30.9% +/- 5.5% with E1S, decreased by 7.2% +/- 5.0% with 17 alpha-dihydroequilin sulfate, and, with the combination, significantly increased by 10.5% +/- 2.4% compared with baseline. Changes in lipids and lipoproteins were more variable. However, high-density-lipoprotein cholesterol increased significantly with E1S at 30 and 90 days compared with baseline, 96.5% +/- 39% and 91.5% +/- 22.6%, and with the combination increased 66.4% +/- 13.3% and 79.2% +/- 24.4%, respectively. Fewer changes were evident with 17 alpha-dihydroequilin sulfate alone, decreasing 4.4% +/- 22% and 2.6% +/- 21.3%. Urinary ratios of bone collagen equivalents-creatinine and calcium-creatinine decreased in all three groups. However, the combination group resulted in a significantly greater percentage decrease in bone collagen equivalents-creatinine than with E1S alone. CONCLUSIONS(S): 17 alpha-Dihydroequilin sulfate could modify some of the first-pass effects of conjugated equine estrogens and act synergistically with other conjugated equine estrogens to reduce bone resorption.  相似文献   
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PURPOSE: Our purpose was to determine the utility of functional MR imaging in conjunction with a word-generation paradigm in the assessment of language lateralization. METHODS: Functional MR imaging and Wada testing for language lateralization was performed in patients with complex partial seizures during the performance of word-generation tasks. A language lateralization quotient was calculated from the number of activated pixels in the right and left hemispheres. A language laterality score was derived from the Wada results as the percentage of correct responses during right internal carotid artery injection minus the percentage of correct responses during left internal carotid injection. A correlation coefficient between the functional MR imaging results and the Wada language laterality scores was calculated. RESULTS: In 13 patients, hemispheric dominance based on Wada testing was confirmed by functional MR imaging during silent word generation. The Wada laterality scores varied from 100 to -100 and the functional MR imaging scores varied from 100 to -10. The language lateralization scores determined by functional MR imaging correlated significantly with the language lateralization scores derived from Wada testing. CONCLUSION: Functional MR imaging performed during word generation is an accurate method for lateralizing language function in patients with complex partial epilepsy.  相似文献   
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AIM: To study the effect of nimodipine (Nim) on ischemic cerebral damage. METHODS: The four-vessel occlusion method was performed on rats. Monoamines were measured by fluorospectrophotometry. RESULTS: Intraperitoneal injection of Nim 0.75 and 1.5 mg.kg-1 quickened the recovery of EEG changes to 19 +/- 3 and 17 +/- 4 min (P < 0.01), respectively. Nim reduced the decreases of monoamines (NE, DA, 5-HT, and 5-HIAA) contents after 30-min cerebral ischemia and 1-h reperfusion. CONCLUSION: Nim protects the brain from ischemic damage.  相似文献   
8.
Persistent sciatic is a vascular malformation resulting in the embryo from the preferential growth of the ischiatic posterior axis remaining atrophic. We report here two cases of unilateral, complete and incompleted, persistent sciatic arteries, complicated by buttock aneurysm.  相似文献   
9.
Tumor lysis syndrome (TLS) is a critical illness with few treatment options. This report describes the clinical course of a patient with non-Hodgkin's lymphoma, who developed TLS and required renal replacement therapy. Institution of the standard therapeutic approach, intermittent hemodialysis, was not possible because of persistent hypotension. Instead, the patient was treated with a short course of continuous arteriovenous hemofiltration (CAVH) and conventional continuous arteriovenous hemodialysis (CAVHD) with dialysate flow rate of 1 L/h), which resulted in effective control of serum uric acid, potassium, urea nitrogen, phosphorus, and extracellular fluid volume. This case is in distinction to a previous report of TLS treatment with CAVHD using 4 L/h dialysate flow rate. We conclude that continuous renal replacement therapies with standard dialysate flow rates and replacement volumes should be considered for the treatment of TLS, particulary if the syndrome is accompanied by hypotension.  相似文献   
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