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31.
The objective of this study was to investigate the effects of the herbicide 3-amino-1,2,4-triazole (AMT) on the activities of catalase and lactate dehydrogenase (LDH) in blood (plasma and erythrocytes) and eight solid tissues of goldfish, Carassius auratus. Injection of goldfish with AMT (0.5 mg/gww AMT in 0.9% NaCl) resulted in a significant decrease in catalase activity 24 h post-injection in most tissues investigated. In white and red muscle, kidney, heart, liver, brain and erythrocytes the activity of catalase decreased by 61%, 69%, 64%, 48%, 40%, 27% and 26%, respectively, in comparison to the values seen in animals injected with physiological saline (0.9% NaCl). However, the activity of LDH decreased only in red muscle (by 19%) after AMT injection, whereas in plasma it increased by 137%. Protein carbonyl levels, a measure of oxidative damage to proteins, did not change in plasma in goldfish injected with AMT and total hemoglobin levels in AMT-injected fish, although lower compared with uninjected controls, did not differ from values in saline-injected controls. It is proposed that catalase activity in erythrocytes and white muscle might be usefully developed as a potential marker for fish intoxication by aminotriazole and other related herbicides.  相似文献   
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The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing the end of 1 +/- 0.5 million years of massive volcanism in East Greenland, are coeval. The relative age of Danish Ash-17 thus places the PETM onset after the beginning of massive flood basalt volcanism at 56.1 +/- 0.4 million years ago but within error of the estimated continental breakup time of 55.5 +/- 0.3 million years ago, marked by the eruption of mid-ocean ridge basalt-like flows. These correlations support the view that the PETM was triggered by greenhouse gas release during magma interaction with basin-filling carbon-rich sedimentary rocks proximal to the embryonic plate boundary between Greenland and Europe.  相似文献   
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Tepary bean (Phaseolus acutifolius var. latifolius), a potential arid‐land legume crop, was analyzed for total protein, oil, fiber and mineral content. Results indicate the bean would be adequate in these nutrients for a human diet if deficient amino acids in the seed‐protein were complimented.  相似文献   
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The aim of this study was to investigate the course of expression of platelet‐activating factor (PAF), PAF‐receptor (PAF‐R), epidermal growth factor (EGF), EGF‐R, vascular endothelial growth factor (VEGF), VEGF‐R1 and VEGF‐R2 in uterine tissue during canine pregnancy. For this purpose, 20 bitches were ovariohysterectomized at days 10–12 (n = 10), 18–25 (n = 5) and 28–45 (n = 5) days after mating, respectively. The pre‐implantation group was proven pregnant by embryo flushing of the uterus after the operation, the others by sonography. Five embryo negative, that is, non‐pregnant, bitches in diestrus (day 10–12) served as controls. Tissue samples from the uterus (placentation sites and horn width, respectively) were excised and snap‐frozen in liquid nitrogen after embedding in Tissue Tec®. Extraction of mRNA for RT‐PCR was performed with Tri‐Reagent. In the embryos, mRNA from all factors except VEGF was detected. In the course of pregnancy, significantly higher expression of PAF and PAFR as well as VEGF and VEGFR2 during the pre‐implantation stage than in all other stages and a strong upregulation of EGF during implantation were characteristic. The course of EGF was in diametrical opposition to the course of the receptor. These results point towards an increased demand for VEGF, EGF and PAF during the earliest stages of canine pregnancy.  相似文献   
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Organic farming (OF) has significantly increased in importance in recent decades. Disease management in OF is largely based on the maintenance of biological diversity and soil health by balanced crop rotations, including nitrogen‐fixing and cover crops, intercrops, additions of manure and compost and reductions in soil tillage. Most soil‐borne diseases are naturally suppressed, while foliar diseases can sometimes be problematic. Only when a severe disease outbreak is expected are pesticides used that are approved for OF. A detailed overview is given of cultural and biological control measures. Attention is also given to regulated pesticides. We conclude that a systems approach to disease management is required, and that interdisciplinary research is needed to solve lingering disease problems, especially for OF in the tropics. Some of the organic regulations are in need of revision in close collaboration with various stakeholders. © 2015 Society of Chemical Industry  相似文献   
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Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep.  相似文献   
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OBJECTIVES: To identify the prevalence of Borzoi chorioretinopathy in western Canada, characterize lesions with fluorescein angiography, determine if lesions were progressive, clarify the association of progressive retinal atrophy and investigate the etiology. MATERIALS AND METHODS: Serial ophthalmic examination, fundus photography, electroretinography, and fluorescein angiography were used to evaluate Borzoi dogs with lesions of Borzoi chorioretinopathy. Pedigree analysis and test breeding of two affected dogs were completed to determine the heritability of Borzoi chorioretinopathy. RESULTS: One hundred three Borzoi dogs were examined between 1998 and 2003. Focal, peripheral, tapetal, hyper-reflective and pigmented areas consistent with focal retinal degeneration and RPE pigmentation were identified in 12 dogs between 7 months and 7 years of age. Seven males and five female dogs were affected. Ophthalmoscopy and fundus photography over 5 years revealed individual lesions that did not progress or coalesce in 12 affected dogs. Electroretinography of affected and normal Borzoi dogs confirmed that retinal function was similar in normal and affected dogs up to 7 years of age. Fluorescein angiography was performed in three affected dogs and confirmed intact blood-ocular barriers, focal retinal pigment epithelium hypertrophy, and focal absence of choroiocapillaris corresponding to chronic, focal lesions. Pedigree analysis precluded simple dominant, X-linked dominant, or X-linked recessive inheritance. One male dog from the test-bred litter developed bilateral lesions at 14 months of age. Simple recessive, polygenetic, and acquired etiologies of these lesions cannot be ruled out at this time. CONCLUSIONS: Borzoi chorioretinopathy is an acquired condition that initially manifests as focal retinal edema and loss of choriocapillaris and tapetum. With time the retina degenerates becoming hyper-reflective and with RPE hyper-pigmentation and clumping within the borders of the tapetal lesions. Choriocapillaris remains hypofluorescent on fluorescein angiography. Progressive retinal atrophy was excluded as an etiology of multifocal chorioretinopathy in Borzois dogs. This condition is not inherited by simple autosomal dominant or sex-linked modes of inheritance.  相似文献   
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