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排序方式: 共有436条查询结果,搜索用时 734 毫秒
61.
Hazel Wetzstein S. C. Myers 《The Journal of Horticultural Science and Biotechnology》2013,88(4):747-753
SUMMARYEvaluations were made of the field performance of micropropagated (tissue cultured axillary buds) versus conventionally rooted softwood cuttings of muscadine grape, Vitis rotundifolia Michx. Trunk cross-sectional area did not differ between treatments during three years of field evaluation following planting. There were no differences in leaf area and dry weight or shoot number in the two propagation types; leaf morphology was normal with no apparent juvenile characteristics. Yield components including flower number per shoot and inflorescence, fruit number, total fruit weight and yield efficiency were greater in micropropagated plants during the second year, the first year of cropping; differences diminished and yield components were not different in year three. Performance of tissue cultured plants was therefore as good as, or surpassed, conventionally propagated plants during early vine establishment. 相似文献
62.
Janzen AM Wiles D Myers S Marqués FJ 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(12):1345-1349
A juvenile Cashmere goat was evaluated and treated for generalized pustular and crusting dermatitis. A diagnosis of pemphigus foliaceus was made based on histopathology and immunohistochemistry. Treatment with prednisolone resulted in resolution of the lesions. Despite tapering doses and combination with methylprednisolone for monthly maintenance, the kid was euthanized for poor growth and fiber quality. 相似文献
63.
Snead E Vargo C Myers S 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(10):1129-1134
Glucocorticoid-deficient hypoadrenocorticism (GDH) with immune-mediated-neutropenia (IMN) and -thrombocytopenia (IMT) were diagnosed in a 3-year-old Labrador retriever dog. Glucocorticoid-deficient hypoadrenocorticism is rare and diagnostically challenging as clinical signs and laboratory abnormalities are often nonspecific. Immune-mediated cytopenias and other autoimmune disorders, as part of an autoimmune polyglandular syndrome have been reported with hypoadrenocorticism in humans. This is the first reported case of hypoadrenocorticism and bicytopenia in a dog. 相似文献
64.
Spacil Michael M. Rodgers John H. Castle James W. Murray Gulde Cynthia L. Myers James E. 《Water, air, and soil pollution》2011,220(1-4):301-312
Water, Air, &; Soil Pollution - Effective and reliable treatment is needed to treat selenium (Se) in petroleum refinery effluents to meet water discharge limits established under the Clean Water... 相似文献
65.
Cyclization of the phosphate side chain of adenosine triphosphate: formation of monoadenosine 5'-trimetaphosphate 总被引:1,自引:0,他引:1
Monoadenosine 5'-trimetaphosphate has been prepared from adeno-sine 5'-triphosphate by a carbodiimide-mediated condensation. The molecule was characterized by (3l)P nuclear magnetic resonance, and its (31)P spectrum was simulated through the assumption of a three-phosphorus spin system. The molecule is highly reactive and is rapidly converted to adenosine triphosphate upon contact with water. 相似文献
66.
Mehmet E. Göre Nedim Altın Kevin Myers David E. L. Cooke William E. Fry Göksel Özer 《Plant pathology》2021,70(4):898-911
Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey. 相似文献
67.
Toshiyuki Komori Patricia N. Myers Shigehiro Yamada Tomoaki Kubo Hidemasa Imaseki 《Euphytica》2000,116(2):121-130
Sixty Nicotiana species were examined for tolerance against various osmotica for seed germination and seedling growth in vitro. The species showed a wide variety of tolerance, and based on the results of the in vitro tests, 31 species were selected and further evaluated for salt and drought tolerance in a glasshouse. The degrees of tolerance
of germination among the 57 species toward NaCl were approximately related to those toward mannitol, indicating that the osmolarity
plays a majorrole in seed germination. However, the responses during the seedling growth differed in NaCl and mannitol or
drought, and there was no correlation between salt and drought tolerance. Based on the responses in vitro and in the glasshouse, N. paniculata and N. excelsior were selected as the salt tolerant species, and N. arentsii as the salt sensitive species. The degrees of accumulation of dry matter and of Na+ in the leaves were different in the two tolerant species; during NaCl treatment, N. paniculata and N. arentsii accumulated less dry matter relative to the control plants than N. excelsior, and N. paniculata accumulated more Na+ in its leaves than N. excelsior and N. arentsii. It is assumed that the two salt tolerant species have different mechanisms for tolerance to the salt.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
68.
SJ Glaser T Schulte-Herbruggen M Sieveking O Schedletzky NC Nielsen OW Sorensen C Griesinger 《Science (New York, N.Y.)》1998,280(5362):421-424
Experiments in coherent magnetic resonance, microwave, and optical spectroscopy control quantum-mechanical ensembles by guiding them from initial states toward target states by unitary transformation. Often, the coherences detected as signals are represented by a non-Hermitian operator. Hence, spectroscopic experiments, such as those used in nuclear magnetic resonance, correspond to unitary transformations between operators that in general are not Hermitian. A gradient-based systematic procedure for optimizing these transformations is described that finds the largest projection of a transformed initial operator onto the target operator and, thus, the maximum spectroscopic signal. This method can also be used in applied mathematics and control theory. 相似文献
69.
Are extinctions of marine vertebrates as rare and unlikely as current data indicate? Long-term research surveys on the continental shelf between the Grand Banks of Newfoundland and southern New England reveal that one of the largest skates in the northwest Atlantic, the barndoor skate (Raja laevis), is close to extinction. Forty-five years ago, research surveys on St. Pierre Bank (off southern Newfoundland) recorded barndoor skates in 10% of their tows; in the last 20 years, none has been caught, and this pattern of decline is similar throughout the range of the species. 相似文献
70.
The effects of maturity on grain quality and wet‐milling properties were investigated for two hybrids of corn. Significant differences for hybrid and maturity were observed for all grain quality parameters. Test weight, absolute density, and thousand‐grain weight all increased as the corn matured. Kernel hardness increased and breakage susceptibility varied with increased maturity. Water uptake parameters decreased with maturity of the grain. The starch yield results from wet milling showed that the starch yield increased significantly within each cultivar in the early stages of grain maturity, but there were no significant differences between hybrids. Mathematical models using selected grain quality parameters accurately predicted trends in starch yield for the immature and mature corn samples in this study. 相似文献