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331.
Disseminated encephalitozoonosis was diagnosed in 2 sibling, juvenile, cotton-top tamarins (Saguinus oedipus) and 3 sibling, neonatal, emperor tamarins (S. imperator) by use of histologic examination, histochemical analysis, electron microscopy, and polymerase chain reaction (PCR) analysis with nucleotide sequencing. All tamarins were captive born at zoos in North America and died with no premonitory signs of disease. The main pathologic findings were myocarditis (4/5), hepatitis (3/5), interstitial pneumonia (3/5), skeletal myositis (3/5), meningoencephalitis (2/5), adrenalitis (2/5), tubulointerstitial nephritis (1/5), myelitis (1/5), sympathetic ganglioneuritis (1/5), and retinitis (1/5). Central nervous system lesions were the most prominent findings in cotton-top tamarins. The inflammation was predominantly lymphocytic and suppurative in cotton-top tamarins, whereas emperor tamarins had granulomatous or lymphoplasmacytic lesions. Intralesional periodic acid-Schiff-, gram-, or acid-fast (or all 3)-positive, oval-to-elliptical shaped organisms were found in 1 cotton-top and the 3 emperor tamarins. By electron microscopy, these organisms were consistent with microsporidia of the genus Encephalitozoon. E. cuniculi genotype III was detected by PCR analysis and sequencing in paraffin-embedded brain, lung, and bone marrow specimens from the cotton-top tamarins. Although PCR results were negative for one of the emperor tamarins, their dam was seropositive for E. cuniculi by ELISA and Western blot immunodetection. These findings and recent reports of encephalitozoonosis in tamarins in Europe suggest that E. cuniculi infection may be an emerging disease in callitrichids, causing high neonatal and juvenile mortality in some colonies. The death of 2 less than 1-day-old emperor tamarins from a seropositive dam supports the likelihood of vertical transmission in some of the cases reported here.  相似文献   
332.
377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. 73 fertile isolates were tested with SCAR markers of 13 pairs of primers. Preliminary results showed that the geographic distribution of M. grisea existed among isolates collected from the same location as well as different locations and the genetic relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M. grisea was explored in the field as well.  相似文献   
333.
beta-Casein was quantified in milk and cheese, using an optical immunosensor, based on surface plasmon resonance (SPR) measurement. The assay consists of a two-step sandwich strategy, with two anti-beta-casein antibodies directed against each extremity of the casein. This strategy permits only native beta-casein to be quantified and not its degradation products. The calibration curve was obtained with a reference milk powder of known beta-casein concentration. The analysis time per sample was less than 10 minutes. The antibody-coated surface could be used for more than 250 determinations. The detection limit was established at 85 ng x mL(-)(1) and the intra- and inter-assay variation coefficients were 2.6 and 6.2% respectively. The method was applied to raw milk to quantify intact beta-casein, with no pretreatment of the sample. A second application was realized with cheese, to follow the proteolysis of beta-casein during ripening.  相似文献   
334.
A simple tank system, using artificial aeration to supply oxygen and incoming water to dilute metabolic by-products and other wastes, was tested. Blue tilapia, Oreochromis aureus, were grown under a wide range of loads, 7–31 kg liter−1 min−1, and densities, 19–77 kg fish m−3 culture unit. Average yield ranged from 6–10 kg m−3 culture unit per month. Approximately 14–20 m3 of water was used for each kilogram of fish produced.  相似文献   
335.
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem‐based perspective, using objective and evidence‐based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long‐term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem‐based management and governance, sustainable fisheries and healthy ecosystems go together.  相似文献   
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