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排序方式: 共有398条查询结果,搜索用时 15 毫秒
31.
Pimenta BV Haddad CF Nascimento LB Cruz CA Pombal JP 《Science (New York, N.Y.)》2005,309(5743):1999; author reply 1999
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A. C. Barbosa A. A. Boischio G. A. East I. Ferrari A. Gonçalves P. R. M. Silva T. M. E. da Cruz 《Water, air, and soil pollution》1995,80(1-4):109-121
Mercury (Hg) contamination of miners, riparian and Indian populations and fish in the Amazon region, due to gold extracting activities, has been studied. Samples of hair, urine, and blood of Indians and prospectors, and hair from riparian fish-eating population and fishes from Madeira river, respectively, were collected and analyzed by Cold Vapor, Atomic Absorption Spectrometry (CV-AAS) techniques. The results obtained showed that the aquatic food chains in the Amazonian ecosystems are contaminated by methylmercury (MeHg), exposing Indians, prospectors and riverines to thr risk of severe health hazard. The highest levels of contamination, based upon hair analysis, were found in riparian of the Madeira river, followed by Cuniã Lake population, Indians (Fresco river) and prospectors, in that order. Blood analysis showed 59% of the samples from Indians and 33% from prospectors with Hg contents above 10 ng mL?1. Analysis of urine, on the other hand, showed 44% of Indians with Hg levels below the detection limit (d.l.), and 30% above 20 ng mL?1, whereas 38% of the prospectors presented Hg concentrations over 20 ng mL?1, and 20% below the d.l. These results prove that prospectors, who hardly ever eat fish but are badly exposed to inorganic Hg vapor, are ocupationally contaminated, while the rest of the populations under survey are exposed to environmental contamination by Hg, through polluted fish ingestion. 相似文献
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de Carvalho Menezes de Almeida Sheylla Foligno Souza-Fabjan Joanna Maria Gonçalves Balaro Mario Felipe Alvarez Bragança Gláucia Mota Pinto Pedro Henrique Nicolau de Almeida José Gabriel Moura Ana Beatriz Bossois da Fonseca Jeferson Ferreira Brandão Felipe Zandonadi 《Tropical animal health and production》2018,50(2):427-432
Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes... 相似文献
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A.G. Becker J.F. Gonçalves L.O. Garcia E.R. Behr F.J.K. Mallmann D.L. Graça B. Baldisserotto 《Fish physiology and biochemistry》2006,32(2):105-112
The levels of various ions (Na+, Cl−, Ca2+, Mg2+, K+) in the fluid phase of the gastrointestinal contents and of the plasma were determined in four teleosts with different feeding habits: traira (Hoplias malabaricus), hassar (Hoplosternum littorale), silver catfish (Rhamdia quelen), and grass carp (Ctenopharyngodon idella). The results showed that most ionic levels in the fluid phase of the gastrointestinal tract seem to be affected by feeding habit and that these levels can be different from those found in the plasma. In practical terms, these results suggest that ionic levels of the gastrointestinal contents should be considered when preparing solutions for studies of intestinal absorption in fishes. 相似文献
36.
Rui A. Gonçalves Tu Do Cam Nguyen Nhu Tri Gonçalo A. Santos Pedro Encarnação Le Thanh Hung 《Aquaculture International》2018,26(3):921-936
Triplicate groups of one hundred Tra catfish (8 g?±?0.2) were fed seven test diets containing increasing levels of AFB1 (0, 50, 100, 250, 500, and 1000 μg AFB1 kg?1). Additionally Mycofix® Secure was added at 1.5% to one diet containing 500 μg AFB1 kg?1. Results showed that Tra catfish are sensitive to AFB1. Reduction in weight gain (P?<?0.05) was observed for fish fed 50 μg AFB1 kg?1 and declined further with increasing levels of AFB1 in the diets. Fish fed diets contaminated with 500 and 1000 μg AFB1 kg?1 showed increased (P?>?0.05) hepatosomatic index (HIS), while an increase in adipose somatic index (ASI) was observed in fish fed 50 μg AFB1 kg?1 and above when compared to the control and Mycofix® diets. After 12 weeks, blood serum analysis revealed higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in fish fed the 50, 100, and 250 μg AFB1 kg?1 suggesting occurrence of liver damage. Disease resistance of fish exposed to Edwardsiella ictaluri was also compromised by the presence of AFB1 in the feed and was directly related to the contamination level. Seven days after Edwardsiella ictaluri exposure, survival rates were 50, 41.7, 31.7, and 8.3% for fish fed control, 50, 100, and 250 μg AFB1 kg?1, respectively. This trial shows that AFB1 at a level of 50 μg AFB1 kg?1 and above can affect fish performance and disease resistance. Application of an effective mycotoxin management in the feed seems to be useful to prevent the negative effects of AFB1. 相似文献
37.
Annette Herz Sherif A. Hassan Esmat Hegazi Feeby N. Nasr Ali A. Youssef W. E. Khafagi Essam Agamy Mohieddine Ksantini Taieb Jardak Basilis E. Mazomenos Maria A. Konstantopoulou Laura Torres Fátima Gonçalves Albino Bento José A. Pereira 《Gesunde Pflanzen》2005,57(5):117-128
Zusammenfassung Traditionelle, extensiv bearbeitete Olivenhaine, aber auch moderne Intensiv-Plantagen mit künstlicher Bewässerung und hohem Einsatz von Düngern bzw. chemischen Pflanzenschutzmitteln kennzeichnen die derzeitigen verschiedenen Anbauformen der Olive im Mittelmeerraum. Schadlepidopteren wie die Olivenmotte (Prays oleae, Lep.: Yponomeutidae) und die Jasminmotte (Palpita unionalis, Lep.: Pyralidae) werden durch regelmässigen Insektizideinsatz bekämpft. Das von der EU geförderte internationale Forschungsprojekt TRIPHELIO zielte auf die Entwicklung insektizidfreier Alternativmethoden durch (1) die Optimierung der pheromongestützten Überwachung und Verwirrtechnik, (2) der Anwendung von Habitatmanagement-Strategien zur Förderung natürlicher Gegenspieler, und (3) dem Einsatz von Trichogramma-Schlupfwespen. Zusätzlich wurden Module für eine optimale Anwendung biotechnischer und biologischer Methoden bezüglich der Phänologie der Schadinsekten und möglicher Nebenwirkungen von Pestiziden erarbeitet. Die intensive Kooperation zwischen Wissenschaftlern und Praktikern aus mehreren Ländern Europas und Nordafrikas erlaubte den Entwurf möglicher Lösungsansätze für verschiedene Anbaubedingungen und klimatische Regionen des Mittelmeerraumes. Die wichtigsten Ergebnisse und Ausblicke für eine zukünftige praktische Umsetzung werden in dieser Veröffentlichung beschrieben. 相似文献
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Roberto dos Santos Trindade Rosana Rodrigues Ant?nio Teixeira do Amaral Júnior Leandro Sim?es Azeredo Gon?alves Rogério Figueiredo Daher Cláudia Pombo Sudré 《Journal of General Plant Pathology》2012,78(3):201-206
Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) is the main bacterial disease of snap bean. The present work aimed to select snap bean genotypes that are resistant to CBB based on three components of resistance: area under the disease progress curve, latent period, and lesion diameter on pods (DL). A completely randomized two-factor factorial design with six replications was used to evaluate leaves and pods of 14 snap bean and three common bean genotypes (PI 207262, BAC-6 and A-794) with high resistance to CBB. Two Xap isolates, 1394-98 and 775-90, were used to inoculate leaves and pods. Data were analyzed using nonparametric statistics. Significant differences were observed among the evaluated genotypes for all of the components of resistance, except for DL. The snap bean UENF 1482 demonstrated good performance in two disease resistance components. For this reason, this genotype can be recommended for use in breeding programs that aim to generate snap bean genotypes resistant to Xanthomonas axonopodis pv. phaseoli. 相似文献
40.
Arrol L Penderis J Garosi L Cripps P Gutierrez-Quintana R Gonçalves R 《The Veterinary record》2012,170(13):335
The aetiology and outcome of dogs with juvenile-onset seizures were investigated. One hundred and thirty-six dogs whose first seizure occurred before the age of one year were investigated. One hundred and two dogs were diagnosed with idiopathic epilepsy (IE), 23 with symptomatic epilepsy (SE), nine with reactive seizures (RS) and two with probable symptomatic epilepsy (pSE). The outcome was known in 114 dogs; 37 per cent died or were euthanased as a consequence of seizures. The mean survival time of this population of dogs was 7.1 years. Factors that were significantly associated with survival outcome included the diagnosis of SE and the number of antiepileptic drugs (AEDs) used before investigation. The use of one AED before investigation and a diagnosis of SE were associated with a negative outcome, whereas receiving no AED medications before referral was associated with a longer survival. For dogs with IE, survival time was shortened if the dog was a border collie or with a history of status epilepticus;receiving no AEDs before referral in the IE group was associated with a positive outcome. Seizure-free status was achieved in 22 per cent of dogs diagnosed with IE. While the survival times were longer than previously reported in canine epilepsy, similar remission rates to those reported in childhood epilepsy, where a 70 per cent remission rate is documented, were not seen in the canine juvenile population. 相似文献