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101.
Graeme Chandler 《Soil biology & biochemistry》1985,17(3):347-353
Examination of three forest soils from Malaysia using the soil incubation technique suggests that nitrification was not inhibited in these oligotrophic soils. Nitrification rates were between 40 and 750 ngN produced g?1 dry weight soil day?1 of incubation. Addition of phenolic metabolites (tannic acid) and leaf filtrates from hill and lowland forest litter did not significantly inhibit nitrification. Addition of sucrose (1% w/w carbon source) decreased nitrification but not ammonification. 相似文献
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B A Valentine S K Chandler J F Cummings B J Cooper 《American journal of veterinary research》1991,52(1):104-107
Explants were prepared from skeletal muscle tissue from 5 nondystrophic pups and from 5 pups with X-linked muscular dystrophy; pups were 2 to 17 weeks old. A serial reexplant method resulted in optimal cell density with minimal fibroblast growth. Cultures were examined daily by use of phase-contrast microscopy; differentiated (post-fusion) cultures were examined by electron microscopy. Moderate nuclear pleomorphism and cell clustering were observed in cultures of normal and dystrophic muscle cells. Cultures were maintained to 27 days after plating. Minimal myofilament synthesis was observed in multinucleate cells from nondystrophic and dystrophic pups, but spontaneous contraction of myotubes was not observed during this period. Differences in growth, fusion, or differentiation of myogenic cells into multinucleate cells and myotubes were not found between dystrophic and normal muscle. 相似文献
103.
Paradoxical increase in rate of catabolism of low-density lipoproteins after hepatectomy 总被引:5,自引:0,他引:5
It has been suggested that the liver may be a major site for irreversible degradation of low-density lipoprotein (LDL). The disappearance of autologous (125)I-labeled LDL from plasma was compared in intact and in hepatectomized swine. Contrary to expectations, the rate of irreversible removal of LDL from plasma was increased rather then decreased by hepatectomy. These studies suggest that the liver is not a major site for LDL removal. We propose further that the liver (or some function requiring an intact liver) may affect the metabolism of LDL in a manner that prolongs its lifetime in the plasma compartment. 相似文献
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The van der Waals picture focuses on the differing roles of the strong short-ranged repulsive intermolecular forces and the longer ranged attractions in determining the structure and dynamics of dense fluids and solids. According to this physical picture, the attractive interactions help fix the volume of the system, but the arrangements and motions of molecules within that volume are determined primarily by the local packing and steric effects produced by the repulsive forces. This very useful approach, its limitations, and its successful application to a wide variety of static and dynamic phenomena in condensed matter systems are reviewed. 相似文献
107.
B. Niemiec J. Gawor A. Nemec D. Clarke K. McLeod C. Tutt M. Gioso P. V. Steagall M. Chandler G. Morgenegg R. Jouppi K. McLeod 《The Journal of small animal practice》2020,61(7):395-403
Dental, oral, and maxillofacial diseases are some of the most common problems in small animal veterinary practice. These conditions create significant pain as well as localized and potentially systemic infection. As such, the World Small Animal Veterinary Association (WSAVA) believes that un- and under treated oral and dental diseases pose a significant animal welfare concern. Dentistry is an area of veterinary medicine which is still widely ignored and is subject to many myths and misconceptions. Effective teaching of veterinary dentistry in the veterinary school is the key to progression in this field of veterinary medicine, and to the improvement of welfare for all our patients globally. These guidelines were developed to provide veterinarians with the information required to understand best practices for dental therapy and create realistic minimum standards of care. Using the three-tiered continuing education system of WSAVA, the guidelines make global equipment and therapeutic recommendations and highlight the anaesthetic and welfare requirements for small animal patients. This document contains information on common oral and dental pathologies, diagnostic procedures (an easily implementable and repeatable scoring system for dental health, dental radiography and radiology) and treatments (periodontal therapy, extractions). Further, there are sections on anaesthesia and pain management for dental procedures, home dental care, nutritional information, and recommendations on the role of the universities in improving veterinary dentistry. A discussion of the deleterious effects of anaesthesia free dentistry (AFD) is included, as this procedure is ineffective at best and damaging at worst. Throughout the document the negative effects of undiagnosed and/or treated dental disease on the health and well-being of our patients, and how this equates to an animal welfare issue, is discussed. 相似文献
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Munn DH Sharma MD Lee JR Jhaver KG Johnson TS Keskin DB Marshall B Chandler P Antonia SJ Burgess R Slingluff CL Mellor AL 《Science (New York, N.Y.)》2002,297(5588):1867-1870
Antigen-presenting cells (APCs) can induce tolerance or immunity. We describe a subset of human APCs that express indoleamine 2,3-dioxygenase (IDO) and inhibit T cell proliferation in vitro. IDO-positive APCs constituted a discrete subset identified by coexpression of the cell-surface markers CD123 and CCR6. In the dendritic cell (DC) lineage, IDO-mediated suppressor activity was present in fully mature as well as immature CD123+ DCs. IDO+ DCs could also be readily detected in vivo, which suggests that these cells may represent a regulatory subset of APCs in humans. 相似文献