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141.
Wolfgang Stotz 《Aquaculture International》2000,8(2-3):237-247
The fishery for Argopecten purpuratus in northern Chile, whichcollapsed because of overfishing, has been replaced by aquaculture of thespecies. In 1998, cultures produced 16,474 t, while the highest landings recorded inthe entire history of the fishery was in 1984 (one year after the 1983 ElNiño) with 5275 t. The figures for stock size of the species in the pastand at present, show that the wild stock of scallops today represents notmore than 10–15% of the total stock of the species within Chile, with mostof the individuals being kept in sea farms. Thus it is concluded that thescallop already represents a domestic species and, considering theoccurrence and development of selection practices in sea farms,biodiversity within the species appears to be at risk. With the developmentof culture practices over its entire range, there is little use in trying torecover a wild fishery for this scallop. It is urgent, however, that selectednatural beds be protected in order to preserve genetic diversity. 相似文献
142.
Binding of imidacloprid,thiamethoxam and N‐desmethylthiamethoxam to nicotinic receptors of Myzus persicae: pharmacological profiling using neonicotinoids,natural agonists and antagonists 下载免费PDF全文
143.
Heinz Benkenstein Michael Baumecker Hans Pagel Wolfgang Krüger 《Archives of Agronomy and Soil Science》2013,59(6):523-538
Langjährig unterlassene Kalkung führte bei mineralisch (NPK) und mit Stallmist gedüngtem Boden in den letzten 20 Versuchsjahren zu pH‐Werten von 4,2 bis 3,6. Die Relativerträge nahmen im Vergleich zur mineralischen Volldüngung (NPKCa) ab. Diese Abnahme war von der Pflanzenart abhängig und bei Sommergerste deutlicher als bei Kartoffeln und Mais. Kalkung des mit NPK gedüngten Bodens erhöhte die Erträge bei Mais bereits im ersten Jahr, bei Gerste und Kartoffeln erst nach mehreren Jahren auf das Niveau der Vergleichsvariante. Bei einer Umstellung von Stallmist auf Stallmist + NPKCa glichen sich die Erträge von Mais und Sommergerste im gleichen Jahr, bei Kartoffeln erst nach mehreren Jahren dem langjährig mit Stallmist + NPKCa gedüngten Prüfglied an. Im langjährig ungedüngten Boden fielen pH‐Wert, KDL und PDL in den letzten 20 Versuchsjahren ebenfalls deutlich ab (pH 3,6 bis 4,1; KDL 2,2 bis 5,0 und PDL 3,5 bis 5,5 mg/100 g Boden). In deren Folge und durch N‐Mangel kam es bei Gerste zum Totalausfall und bei Mais nahezu zum Totalausfall. Bei Kartoffeln lag der Ertrag noch bei 15% der Vergleichsvariante NPKCa. Eine Düngung der Mangelparzellen mit NPKCa ließ den pH‐Wert bereits im ersten Jahr, KDL und PDL erst nach mehrmaliger Düngung in den anzustrebenden Bereich ansteigen. Eine Angleichung der Erträge an die Erträge des durchgehend mit NPKCa gedüngten Prüfgliedes dauerte drei bis vier Jahre. 相似文献
144.
145.
Comparative efficacies of oral ketoconazole and terbinafine for reducing Malassezia population sizes on the skin of Basset Hounds 总被引:1,自引:0,他引:1
Guillot J Bensignor E Jankowski F Seewald W Chermette R Steffan J 《Veterinary dermatology》2003,14(3):153-157
The objective of this study was to compare the efficacy of oral ketoconazole and terbinafine for reducing population sizes of Malassezia yeasts on canine skin. Twenty-one Basset Hounds were randomised in three groups of seven according to Malassezia populations. Dogs in the first group were treated by oral administration of ketoconazole (Ketofungol) 200 mg, Janssen-Cilag) at 10 mg x kg-1, every 24 h with food, for 3 weeks. Dogs in the second group were treated by oral administration of terbinafine (Lamisil) 250 mg, Novartis) at 30 mg x kg-1, every 24 h with food, for 3 weeks. The seven remaining dogs were used as controls. Malassezia population sizes were assessed by use of contact plates on four cutaneous sites at days 7, 14 and 21. Both ketoconazole and terbinafine were effective in reducing the baseline levels of Malassezia organisms with no significant difference between the two drugs. In further studies, oral terbinafine should be evaluated for the management of canine cases of Malassezia dermatitis. 相似文献
146.
Meinecke M Wagner R Kovermann P Guiard B Mick DU Hutu DP Voos W Truscott KN Chacinska A Pfanner N Rehling P 《Science (New York, N.Y.)》2006,312(5779):1523-1526
Transport of metabolites across the mitochondrial inner membrane is highly selective, thereby maintaining the electrochemical proton gradient that functions as the main driving force for cellular adenosine triphosphate synthesis. Mitochondria import many preproteins via the presequence translocase of the inner membrane. However, the reconstituted Tim23 protein constitutes a pore remaining mainly in its open form, a state that would be deleterious in organello. We found that the intermembrane space domain of Tim50 induced the Tim23 channel to close. Presequences overcame this effect and activated the channel for translocation. Thus, the hydrophilic cis domain of Tim50 maintains the permeability barrier of mitochondria by closing the translocation pore in a presequence-regulated manner. 相似文献
147.
S Naik N Bouladoux C Wilhelm MJ Molloy R Salcedo W Kastenmuller C Deming M Quinones L Koo S Conlan S Spencer JA Hall A Dzutsev H Kong DJ Campbell G Trinchieri JA Segre Y Belkaid 《Science (New York, N.Y.)》2012,337(6098):1115-1119
Intestinal commensal bacteria induce protective and regulatory responses that maintain host-microbial mutualism. However, the contribution of tissue-resident commensals to immunity and inflammation at other barrier sites has not been addressed. We found that in mice, the skin microbiota have an autonomous role in controlling the local inflammatory milieu and tuning resident T lymphocyte function. Protective immunity to a cutaneous pathogen was found to be critically dependent on the skin microbiota but not the gut microbiota. Furthermore, skin commensals tuned the function of local T cells in a manner dependent on signaling downstream of the interleukin-1 receptor. These findings underscore the importance of the microbiota as a distinctive feature of tissue compartmentalization, and provide insight into mechanisms of immune system regulation by resident commensal niches in health and disease. 相似文献
148.
C Pöhlker KT Wiedemann B Sinha M Shiraiwa SS Gunthe M Smith H Su P Artaxo Q Chen Y Cheng W Elbert MK Gilles AL Kilcoyne RC Moffet M Weigand ST Martin U Pöschl MO Andreae 《Science (New York, N.Y.)》2012,337(6098):1075-1078
The fine particles serving as cloud condensation nuclei in pristine Amazonian rainforest air consist mostly of secondary organic aerosol. Their origin is enigmatic, however, because new particle formation in the atmosphere is not observed. Here, we show that the growth of organic aerosol particles can be initiated by potassium-salt-rich particles emitted by biota in the rainforest. These particles act as seeds for the condensation of low- or semi-volatile organic compounds from the atmospheric gas phase or multiphase oxidation of isoprene and terpenes. Our findings suggest that the primary emission of biogenic salt particles directly influences the number concentration of cloud condensation nuclei and affects the microphysics of cloud formation and precipitation over the rainforest. 相似文献
149.
The decomposition of atmospheric hydrogen in different types of soil was measured. The decomposition of H2 was apparently a first-order reaction. H2 decomposition activity was proportional to the amount of soil with maximum activities at soil water contents of approx. 6–11% (w/w). The activity was lower under anaerobic conditions, but was constant between 1–20% O2. It was destroyed by autoclaving and was partially inactivated by fumigation with NH3, CHC13 or acetone, by u.v. irradiation and by treatment with NaCN or NaN3, indicating that biological processes in the soil were responsible for the observed H2 decomposition. Treatment of soil with toluene or CHCl3 caused only a partial inactivation. Incubation of soil in the presence of streptomycin or actidione reduced H2 decomposition by less than 50%, whereas CO consumption was abolished. The H2 decomposition rates showed H2 saturation curves with apparent Michaelis-Menten kinetics. Cooperative effects were not observed. Vmax was reached at approx. 200 μl1?1. The Km values for H2 were in the range of 30μl 1?1, but increased to higher values, when the soil had been pretreated with high H2 mixing ratios. Apparently, the observed H2 decomposition by soil is not only due to the activity of viable microorganisms, but soil enzymes as well. 相似文献
150.
Price DC Chan CX Yoon HS Yang EC Qiu H Weber AP Schwacke R Gross J Blouin NA Lane C Reyes-Prieto A Durnford DG Neilson JA Lang BF Burger G Steiner JM Löffelhardt W Meuser JE Posewitz MC Ball S Arias MC Henrissat B Coutinho PM Rensing SA Symeonidi A Doddapaneni H Green BR Rajah VD Boore J Bhattacharya D 《Science (New York, N.Y.)》2012,335(6070):843-847