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Baik-Ho Kim Ju-Hwan Lee Soon-Jin Hwang 《Bulletin of environmental contamination and toxicology》2013,90(2):216-221
The removal or mitigation of cyanobacterial bloom and cyanotoxins is a necessity to ensure safe drinking water and recreational water. As a feasible agent to control cyanobacterial bloom, a novel plant-mineral composite (PMC) was developed and optimized through laboratory and field testing over the past 3 years. Based on previous studies, we treated cyanobacterial bloom water (mainly Microcystis and Synechocystis) with 0.05 mg/L PMC at the small eutrophic reservoir; 2 h later, we collected samples and analyzed them in the laboratory. The intra-cellular (c-MC) and dissolved microcystin-LR (d-MC) were measured using an ELISA method. The PMC exhibited a remarkable removal of both c-MC (47.3 %) and d-MC (95.8 %) within 2 days. In addition, notable decreases (on average, 78 % of the control) in the chlorophyll-a, suspended solids, total phosphorus and biochemical oxygen demand values, in zooplankton and in the phytoplankton density (83.9 %) were verified after 48 h. These results indicate that the PMC is more effective in controlling d-MC than c-MC, suggesting a possible method to mitigate such hazardous chemicals as agrochemicals and endocrine disrupters in aquatic ecosystems. 相似文献
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Eun-Ok Im Young Ko Hyenam Hwang Wonshik Chee 《Health care for women international》2013,34(6):575-592
Our purpose in this study was to identify differences in menopausal symptom management among four major ethnic groups in the United States. This was a secondary analysis of the qualitative data from a larger Internet-based study. We analyzed data from 90 middle-aged women in the United States using thematic analysis. We extracted four themes during the data analysis process: (a) “seeking formal or informal advice,” (b) “medication as the first or final choice,” (c) “symptom-specific or holistic,” and (d) “avoiding or pursuing specific foods.” Health care providers need to develop menopausal symptom management programs while considering ethnic differences in menopausal symptom management. 相似文献
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Evidence for active synapse formation or altered postsynaptic metabolism in visual cortex of rats reared in complex environments. 总被引:1,自引:2,他引:1 下载免费PDF全文
W T Greenough H M Hwang C Gorman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(13):4549-4552
Animals placed in complex environments develop greater numbers of visual cortex synapses per neuron than animals housed in standard cages. Increased numbers of synapses could theoretically arise from (i) active formation of new synapses, or (ii) selective stabilization of constitutively produced synapses. The postsynaptic location of polyribosomal aggregates appears to be an indicator of newly forming synapses. In developmental synaptogenesis and adult reactive (to injury) synaptogenesis, polyribosomes are more frequently found at spine synapses and are more likely to appear in the spine head and stem. In the visual cortex of rats from complex environments, there was a greater frequency of spine synapses associated with polyribosomes, relative to rats from individual or group cages. Furthermore, a greater percentage of these spines had polyribosomes in the head and stem region. This suggests that synapses in this region may be actively induced by neural activity arising from the complex environment experience. 相似文献
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The dramatic increase in the incidence of ductal carcinoma in situ (DCIS) of the breast has made it imperative for all clinicians to develop a better understanding of this disease. Although this preinvasive form of breast cancer is not life-threatening, treatment options may include mastectomy, breast-conserving surgery, radiotherapy, or tamoxifen. Current treatment modalities may be overly aggressive because many cases of DCIS may not recur or progress to invasive cancer. Until we are better able to identify those patients at low risk for progression, it is unlikely that current treatment will change. The adequate understanding of risk assessment is fundamental to the treatment planning for DCIS, and physicians are encouraged to include patients in the decision-making process. 相似文献
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Objective : This study evaluated whether a significant reduction in unnecessary appendectomies is possible by performing diagnostic laparoscopy before appendectomy in female patients of child-bearing age, leaving behind the normal-looking appendix. Materials and methods : Sixty-one consecutive female patients between the ages of 15 and 45 years with clinical diagnosis of acute appendicitis were studied prospectively. Diagnostic laparoscopy was performed to detect whether the appendix was inflamed. The appendix was then removed and the result of laparoscopic diagnosis was matched with histological diagnosis. Results : Ten out of the 42 laparoscopically diagnosed appendicitis cases had normal appendices on histological examination. Six out of the 19 laparoscopically diagnosed normal appendices had histological evidence of appendicitis. The sensitivity of laparoscopy was 84% and the specificity was 56.5%. Conclusions : Discrepancies existed between laparoscopic appearance and histological examination in acute appendicitis. The appendices of all those with clinically suspected appendicitis should be removed and sent for histological confirmation. 相似文献