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81.
We investigated the effects of a long-term thinning experiment on the distribution of above-ground biomass of Douglas-fir(Pseudotsuga menziesii [Mirb.]Franco var. menziesii) in a plantation in southern Italy.Allometric equations were used to estimate biomass and partitioning to stem and crown compartments. Variation in biomass stock estimated with allometric equations were evaluated according to seven thinning treatments: geometric-systematic(1 row every 3), selective(light-moderate-heavy), mixed systematic-selective(1 row every 4, 1 row every 5), unthinned(control). Over the experimental period of 13 years, current annual increments of carbon were lower(3.4 Mg ha~(-1)year~(-1)) in control plots than in treated plots. At age 30, plots subjected to light selective thinning showed higher values of above-ground biomass(249.7 Mg ha~(-1)). The biomass harvested with this treatment was 29.3 Mg ha~(-1), and the mean annual increment of carbon over 13 years was 4.8 Mg ha~(-1). Our results showed that light thinning stimulated increase in carbon stock, with a minimal loss of carbon during the treatment and a current annual increment of carbon higher than in control sub-plots and sub-plots thinned using systematic methods. This treatment yielded least carbon emissions and we affirm it has discrete global warming mitigation potential.  相似文献   
82.
Plant Foods for Human Nutrition - Annona cherimola is a tree belonging to the family Annonacea, whose fruit (cherimoya) is very desirable, but its seeds are considered waste. Present in these seeds...  相似文献   
83.
The apoprotein expression and the catalytic activities of cytochrome P450s involved in the biotransformation of xenobiotics were investigated in horse liver microsomes and compared with those of food producing (cattle, pigs, broiler chicks, and rabbits) and laboratory species (rats). Western blot analysis revealed the presence of proteins immunorelated to rat CYP 1A, CYP 2B, CYP 2E, and CYP 3A subfamilies in hepatic microsomes from horses and from any other examined species. With the exception of the N-demethylation of N-nitrosodimethylamine in broiler chicks, all the recorded interspecies differences were quantitative in nature. Equine preparations proved the most active in the biotransformation of the CYP 1A substrates ethoxy- and methoxyresorufin and the least active in the metabolism of aminopyrine and ethoxycoumarin. On a comparative basis, large differences were observed in the rate of the in vitro metabolism of model substrates between "minor" (rabbits, horses) and "major" food producing species. Taken in due consideration the limitations of the in vitro approach, results from this study reinforce the conclusion that studies on drug efficacy and residue depletion should be performed in each target species.  相似文献   
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85.
From the resinous exudate of leaves of Haplopappus multifolius two new coumarins were isolated and assigned the structures 6-hydroxy-7-(5'-hydroxy-3',7'-dimethylocta-2',6'-dien)-oxycoumarin (1) and 6-hydroxy-7-(7'-hydroxy-3',7'-dimethylocta-2',5'-dien)-oxy coumarin (2).  相似文献   
86.
Cryopreserved equine ocular squamous cell carcinoma (SCC) was inoculated subcutaneously into 15 athymic nude and 15 SCID mice. Xenotransplantation resulted in tumor growth in two athymic nude mice and 1 SCID mouse. Histological appearance and immunohistochemical characterization using cytokeratin 5/6 markers and p53 markers of the tumor grown in mice was in full accord with the original equine tumors. No evidence of metastasis was noted in any mouse. This model may serve as a relevant in vivo model for studying the biology of equine ocular SCC and for the testing of new therapeutic modalities.  相似文献   
87.
Application of organic amendments has been proposed as a strategy for the management of diseases caused by soilborne pathogens. However, inconsistent results seriously hinder their practical use. In this work we use an extensive data set of 2423 studies derived from 252 papers to explore this strategy. First, we assess the capability of a specific organic amendment to control different diseases; second, we investigate the influence of organic matter (OM) decomposition on disease suppressiveness; and third, we search for physical, chemical and biological parameters able to identify suppressive OM. OM was found to be consistently suppressive to different pathogens in only a few studies where a limited number of pathogens were tested. In the majority of studies a material suppressive to a pathogen was ineffective or even conducive to other pathogens, suggesting that OM suppressiveness is often pathogen-specific. OM decomposition in many studies (73%, n = 426) emerged as a crucial process affecting suppressiveness. During decomposition, disease suppression either increased, decreased, was unchanged or showed more complex responses, such as ‘hump-shaped’ dynamics. Peat suppressiveness generally decreased during decomposition, while responses of composts and crop residues were more complex. However, due to the many interactions of contributing factors (OM quality, microbial community composition, pathosystem tested and decomposition time), it was difficult to identify specific predictors of disease suppression. Among the 81 parameters analysed, only some of the 643 correlations showed a consistent relationship with disease suppression. The response of pathogen populations to OM amendments was a reliable feature only for some organic matter types (e.g. crop residues and organic wastes with C-to-N ratio lower than ∼15) and for pathogens with a limited saprophytic ability (e.g., Thielaviopsis basicola and Verticillium dahliae). Instead, population responses of the pathogenic fungi Phytophthora spp., Rhizoctonia solani and Pythium spp. appeared unrelated to disease suppression. Overall, enzymatic and microbiological parameters, rather than chemical ones, were much more informative for predicting suppressiveness. The most useful features were FDA activity, substrate respiration, microbial biomass, total culturable bacteria, fluorescent pseudomonads and Trichoderma populations. We conclude that the integration of different parameters (e.g. FDA hydrolysis and chemical composition by 13C NMR) may be a promising approach for identification of suppressive amendments.  相似文献   
88.
To complete a studyaimed at investigating the pattern of the basal activities of liver xenobioticmetabolizing enzymes in major and minor species intended for meat production, microsomal carboxylesterases and some conjugating enzyme activities were determined and compared in liver preparations from horses, cattle, pigs, rabbits and broiler chicks, using the rat as a reference species. Horses and broiler chicks exhibited a lower microsomal carboxylesterase activity towards indophenyl or p-nitrophenyl acetate than that measured in cattle or pig subfractions. Among food-producing species, the rate of glucuronidation of either 1-naphthol or p-nitrophenol was in the order pigs ∼rabbits > horses >> cattle > broiler chicks. The widest variations were observed in the acetylation capacity towards p-aminobenzoic acid or isoniazid, which in rabbits was 3-fold to 11-fold greater than that displayed by any other examined species; low but measurable activities were found in equine and bovine cytosols. The activity of cytosolic glutathione S-transferase (GST) accepting the general substrate 1-chloro-2,4-dinitrobenzene was significantly higher in rabbits, horses and pigs than in rat, broiler chicks and cattle. Finally, an uneven pattern of activity towards the other tested GST substrates – 3,4-dichloronitrobenzene, ethacrinic acid or 1,2-epoxybutane – was observed, possibly reflecting the species-related expression of different GST classes; in this respect, the conjugative capacity displayed by horses was higher than or comparable to that found in the other food-producing species.  相似文献   
89.
A 10-year-old female spayed Vizsla had intermittent mucoid ocular discharge from the right eye for 7 years. History, clinical findings, imaging studies, and culture and histopathology results confirmed chronic dacryocystitis with granuloma. A dacryocystomaxillorhinostomy was performed to preserve the functional portions of the nasolacrimal system remaining in this patient, as well as to promote healing of the lacrimal sac granuloma and secondary infection. Complete resolution of the clinical abnormalities was achieved, and the dog remains healthy 3 years postoperatively.  相似文献   
90.
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