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1.
Hematology and serum biochemistry values are reported for 33 Attwater's prairie chickens (Tympanuchus cupido attwateri) that were captive-reared at the San Antonio Zoo as part of a federal reintroduction program in Texas. Hematologic values include packed cell volume, and total and differential white blood cell counts. The biochemical values include concentrations of serum calcium, total protein, albumin, phosphorus, glucose, uric acid, and cholesterol. Mathematic computation of globulin concentration and albumin: globulin ratios were conducted. Also, determination of the serum activities of creatine kinase and aspartate aminotransferase was done.  相似文献   
2.
本文介绍了社区自然资源管理的5个基本要素:①当地人是自然资源管理的主体,充分赋权于当地人,包括项目决策权、实施参与权、知情监督权、管理维护权、监测评估权;②尊重乡土知识、乡土人才,重视能力建设;③关注农村妇女和弱势群体的参与和能力建设,倡导性别平等及公平的发展观;④在当地村规民约基础上建立社区管理制度和管理组织,促进当地村民的自我管理、自我发展;⑤有偿使用、有偿管理、有偿服务,增强当地村民对项目的拥有感,实现项目的可持续性.  相似文献   
3.
In the Lower Cell of the Heath Steele mine tailings arealocated 50 km north of the city of Miramichi, New Brunswick,Canada, tailings and lime treatment sludge were co-depositedand the effluent occasionally exceeded regulatory dischargelimits for total suspended solids (TSS), especially on verywindy days. A combined field and laboratory investigationwas undertaken during 1998-1999 to identify the cause of thehigh TSS. The methodology included field measurement of windvelocity and sampling of bed tailings, sludge,suspended sediment, and the water cover. The samples werethen subjected to various laboratory examinations using x-raydiffraction, scanning electron microscopy interfacedwith energy dispersion x-ray spectroscopy, critical shearstress measurements, and water chemistry analysis. Thesuspended sediment was found to be composed primarily ofcalcite and metal hydroxides derived from the bed sludge inthe cell. Only a very small amount of tailings (less than5%) was detected in the suspended sediment. The sludge,which covered the tailings in the shallow western section ofthe Lower Cell at depths less than 1 m, was a loose, low-densitymaterial with a low critical shear stress (approximately 0.058 Pa). In shallow water cover (less than 1 m), calculated bed shearstress mobilized by wind-induced waves and return currents exceeded the critical shear on a number of occasions, resultingin resuspension of the sludge and hence high TSS. Although occasional elevated zinc concentrations appeared to follow a similar pattern to high TSS, there was no evidence that thesuspended sludge sediments would release metals into the watercover, due to the high pH of the Lower Cell water cover. Since the tailings did not resuspend significantly, it was clear thatat water cover depth less than 1 m, sludge was eroded instead oftailings, and thus provided a barrier against tailings resuspension. As part of the final closure scheme for the HeathSteele tailings area, sludge and tailings were dredged and relocated from areas where the water cover was < 1 m to deeperwater cover areas to ensure that the effluent met required totalsuspended solids discharge criteria.  相似文献   
4.
Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection.  相似文献   
5.
Pulmonary dysfunction was evaluated in pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV, isolate VR-2332) and compared to clinical and pathological findings. Infected pigs developed fever, reduced appetite, respiratory distress and dullness at 9 days post-inoculation (dpi). Non-invasive pulmonary function tests using impulse oscillometry and rebreathing of test gases (He, CO) revealed peripheral airway obstruction, reduced lung compliance and reduced lung CO-transfer factor. PRRSV-induced pulmonary dysfunction was most marked at 9–18 dpi and was accompanied by a significantly increased respiratory rate and decreased tidal volume. Expiration was affected more than inspiration. On histopathological examination, multifocal areas of interstitial pneumonia (more severe and extensive at 10 dpi than 21 dpi) were identified as a possible structural basis for reduced lung compliance and gas exchange disturbances.  相似文献   
6.
Studies were conducted to evaluate the cell damage caused by exposing human colon carcinoma cells, Caco-2, to hydrogen peroxide at concentrations varying from 0 to 250 microM for 30 min. Evaluation of cell viability, as measured by trypan blue dye exclusion test, showed that the loss of viability was < 5% at concentrations up to 250 microM hydrogen peroxide. Cell membrane damage and DNA damage as measured by the leakage of lactate dehydrogenase and the comet assay, respectively, were significantly high at concentrations >100 microM hydrogen peroxide compared to those of the control. Antioxidant mechanisms in Caco-2 cells were evaluated by measuring catalase, superoxide dismutase, and glutathione peroxidase activities. Catalase activities remained constant in cells treated with 50-250 microM hydrogen peroxide. Superoxide dismutase activity decreased, whereas glutathione peroxidase activity increased in cells treated with H(2)O(2) concentrations of >50 microM. This study showed that with increasing hydrogen peroxide concentration, cell membrane leakage and DNA damage increased, whereas the three antioxidant enzymes responded differently, as shown by mathematical models.  相似文献   
7.
Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion.  相似文献   
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Purpose

The Todos os Santos Bay is the largest bay in Brazil and receives drainage from various watersheds. For more than 450 years, it was the main destination for the domestic and hospital sewage from the city of Salvador, Bahia. With the growing concern regarding the presence of pharmaceutical and personal care products (PPCPs) in the environment, an investigation was undertaken to determine the presence and levels of some commonly used drugs (i.e., atenolol, caffeine, carbamazepine, diazepam, diclofenac, erythromycin, ibuprofen) and personal care products (i.e., galaxolide, tonalide), using sediments as an indicator of their presence in the water column.

Material and methods

Surficial sediment samples from 17 stations located in the intertidal zone of the Todos os Santos Bay and infralittoral zone along the north coast of Salvador were tested for the presence of some PPCPs using LC-MS/MS (for drugs) and GC-MS/MS (for fragrances).

Results and discussion

The PPCPs examined were present in all sediment samples at levels of parts per billion of dry sediment. The highest concentrations were found for the fragrances galaxolide (52.5 ng g?1) and tonalide (27.9 ng g?1), followed by caffeine (23.4 ng g?1) and pharmaceuticals ibuprofen (14.3 ng g?1), atenolol (9.84 ng g?1), carbamazepine (4.81 ng g?1), erythromycin (2.29 ng g?1), diclofenac (1.06 ng g?1), and diazepam (0.71 ng g?1).

Conclusions

Pharmaceuticals were found to be ubiquitous in the sediments of the study areas. The texture of the sediment was an important factor in PPCPs fixation and deposition. The concentrations of all PPCPs had statistically significant positive correlations with the percentage of clay in the sediments.  相似文献   
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