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正池鹭(Ardeola bacchus)在内蒙古夏季见于呼伦贝尔市、赤峰市克什克腾旗和敖汉旗、呼和浩特市哈素海、包头和鄂尔多斯市黄河沿岸、巴彦淖尔市乌梁素海,但未见繁殖记录的报道。哈素海(E 110°56'~111°01',N 40°34'~40°38')位于大青山南部土默川平原北端,在呼和浩特市区向西70km处的土默特左旗境内,是黄河改道而遗留的椭圆形牛轭湖,属于大黑河水系的外流性淡水湖泊,主要水源来自 相似文献
995.
Aydin Ece Bekir Sami Uyamik Akin IŞcan Pelin Ertan M. Ramazan Yiğitolu 《Biological trace element research》1997,59(1-3):31-39
In order to evaluate serum copper and zinc status in children with iron deficiency anemia (IDA), 60 children with IDA aged
1–14 yr and 64 healthy children as controls aged 1–14 yr were included the study. Serum copper levels were higher in children
with IDA (189 ± 49 (Μg/dL) than those of controls (163 ± 37 Μg/dL) (p = 0.001). Serum zinc levels were lower in the patient group (109 ± 59 Μg/dL) than those of control subjects (135 ± 56 Μg/dL)
(p = 0.017). In addition, there were statistically significant negative correlations between hematological parameters and serum
copper levels in the patient group, but not in controls. No correlation between hematological parameters and serum zinc levels
were found in both patient and control groups, except positive correlation between mean corpuscular volume (MCV) and serum
zinc level in patients.
It was concluded that at the time of managing children with IDA, zinc deficiency must be borne in mind and if necessary treatment
should be initiated with zinc. 相似文献
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997.
Silvia Sorce Mario Nuvolone Annika Keller Jeppe Falsig Ahmet Varol Petra Schwarz Monika Bieri Herbert Budka Adriano Aguzzi 《PLoS pathogens》2014,10(12)
Prion infections cause neurodegeneration, which often goes along with oxidative stress. However, the cellular source of reactive oxygen species (ROS) and their pathogenetic significance are unclear. Here we analyzed the contribution of NOX2, a prominent NADPH oxidase, to prion diseases. We found that NOX2 is markedly upregulated in microglia within affected brain regions of patients with Creutzfeldt-Jakob disease (CJD). Similarly, NOX2 expression was upregulated in prion-inoculated mouse brains and in murine cerebellar organotypic cultured slices (COCS). We then removed microglia from COCS using a ganciclovir-dependent lineage ablation strategy. NOX2 became undetectable in ganciclovir-treated COCS, confirming its microglial origin. Upon challenge with prions, NOX2-deficient mice showed delayed onset of motor deficits and a modest, but significant prolongation of survival. Dihydroethidium assays demonstrated a conspicuous ROS burst at the terminal stage of disease in wild-type mice, but not in NOX2-ablated mice. Interestingly, the improved motor performance in NOX2 deficient mice was already measurable at earlier stages of the disease, between 13 and 16 weeks post-inoculation. We conclude that NOX2 is a major source of ROS in prion diseases and can affect prion pathogenesis. 相似文献
998.
Micellisation process for sodium dodecyl sulphate and sodium cholate in 1∶1 molar ratio was investigated in a combined approach, including several experimental methods and coarse grained molecular dynamics simulation. The critical micelle concentration (cmc) of mixed micelle was determined by spectrofluorimetric and surface tension measurements in the temperature range of 0–50°C and the values obtained agreed with each other within the statistical error of the measurements. In range of 0–25°C the cmc values obtained are temperature independent while cmc values were increased at higher temperature, which can be explained by the intensive motion of the monomers due to increased temperature. The evidence of existing synergistic effect among different constituent units of the micelle is indicated clearly by the interaction parameter (β1,2) calculated from cmc values according to Rubingh. As the results of the conductivity measurements showed the negative surface charges of the SDS-NaCA micelle are not neutralized by counterions. Applying a 10 µs long coarse-grained molecular dynamics simulation for system including 30-30 SDS and CA (with appropriate number of Na+ cations and water molecules) we obtained semi-quantitative agreement with the experimental results. Spontaneous aggregation of the surfactant molecules was obtained and the key steps of the micelle formation are identified: First a stable SDS core was formed and thereafter due to the entering CA molecules the size of the micelle increased and the SDS content decreased. In addition the size distribution and composition as well as the shape and structure of micelles are also discussed. 相似文献
999.
Chiral ligand-exchange enantioseparation of aliphatic and aromatic amino acids was successfully performed using a new open-tubular zwitterionic column with tentacle-type polymer stationary phase. The polymeric stationary phase was prepared using 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl), a new reactive monomer. The preparation procedure of the open-tubular column included silanization, in situ graft polymerization with HPMA-Cl, and l-histidine (l-His) modification. l-His was used as a chiral ligand-exchange selector and copper(II) as a central ion. Successful enantioseparation of six pairs of amino acid enantiomers was achieved with a buffer of 5 mM CuSO4, 20 mM (NH4)2SO4 at pH 3.0. 相似文献
1000.
We evaluated the effects of Ankaferd Blood Stopper (ABS) and routine antibiotic prophylaxis (AP) on early healing of bone defects in diabetic rats. We used 48 rats in the study. Diabetes was induced in 24 rats using streptozotocin; the remaining 24 healthy untreated rats served as controls. Twelve of the diabetic rats and 12 of the healthy rats were treated with AP for 3 days before surgery. Bilateral bone defects were created in the mandible of all animals. ABS was applied to the defects on the left sides of the mandibles, while nothing was applied to the right sides. Animals were sacrificed on days 7 and 14 after operation and examined for histopathology and by stereology. The volume of newly formed bone was significantly less in the diabetic rats on both days 7 and 14. Local administration of ABS significantly increased the mean volume of newly formed bone in both diabetic and nondiabetic rats at days 7 and 14. No significant difference in new bone formation was found between AP and ABS treatment in diabetic rats. Both AP and local administration of ABS have beneficial effects on bone healing in diabetic animals. 相似文献