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排序方式: 共有173条查询结果,搜索用时 234 毫秒
91.
Chow GC 《Science (New York, N.Y.)》1987,235(4786):295-299
Before 1978 in China, the economic institutions for agriculture and industry operated essentially under a centrally planned system. The reasons for a change toward a more market-oriented economy and the key elements of economic reform are discussed. Today the major issues being deliberated by the leading economic officials include reform of the price system, the administrative structure of state-owned enterprises, the banking system and macroeconomic control mechanisms, and foreign trade and investment. 相似文献
92.
93.
Eric P. Chow DVM 《Journal of Exotic Pet Medicine》2011,20(3):182-187
Clinical signs associated with otic disease in rabbits (Oryctolagus cuniculus) are very similar to those demonstrated in dogs and cats. The surgical treatment options to resolve diseases involving the rabbit ear are also comparable with those used for canine and feline species. However, there are key anatomic and physiologic differences that must be accounted for to perform proper surgical treatment on a rabbit that has been diagnosed with ear disease. This article describes the diagnostic and treatment options for otitis externa, otitis media, and otitis interna, with an emphasis on surgical procedures and the important distinctive otic features of the rabbit patient. The ventral bulla osteotomy procedure is recommended for management of otitis media in rabbits without otitis externa. In rabbits with pathology in the external ear canal and the middle ear, total ear canal ablation and lateral bulla osteotomy should be performed. This combined procedure will allow the surgeon to address pathology in both sites, with the ultimate goal of resolution of the underlying disease etiology. Lateral ear canal resection is only appropriate in rabbits with otitis externa without otitis media; however, this surgical procedure may not resolve the otitis externa. If this is a concern, a total ear canal ablation should be done because it offers a greater chance of success. 相似文献
94.
A comparison of ultrahigh performance liquid chromatography (UHPLC) with a 2.6 μm core-shell particle column (Kinetex C(18)) and conventional liquid chromatography (LC) with a 3 μm porous particle column (Atlantis dC(18)), coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS), for the determination of 151 pesticides in grains is presented in this study. Pesticides were extracted from grain samples using a procedure known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). Quantification, with an analytical range from 5 to 500 μg/kg, was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated using a designed experiment, that is, the nested design. The UHPLC (Kinetex C(18)) was superior to conventional LC (Atlantis dC(18)) as it yielded a shorter analytical run time, increased method sensitivity, and improved method performance. For UHPLC/ESI-MS/MS (Kinetex C(18)), 90% of the pesticides studied had recoveries between 81 and 110%, 88% of the pesticides had intermediate precision ≤20%, and 84% of the pesticides showed measurement uncertainty ≤40%. As compared to UHPLC/ESI-MS/MS (Kinetex dC(18)), the LC/ESI-MS/MS (Atlantis dC(18)) showed a relatively lower sensitivity, less repeatability, and larger measurement uncertainty. UHPLC/ESI-MS/MS with 2.6 μm core-shell particle column and scheduled MRM proved to be a good choice for quantification or determination of pesticides in grains. 相似文献
95.
Clathrin light chains LCA and LCB are similar, polymorphic, and share repeated heptad motifs 总被引:19,自引:0,他引:19
T Kirchhausen P Scarmato S C Harrison J J Monroe E P Chow R J Mattaliano K L Ramachandran J E Smart A H Ahn J Brosius 《Science (New York, N.Y.)》1987,236(4799):320-324
The clathrin light chains fall into two major classes, LCA and LCB. In an intact clathrin triskelion, one light chain, of either class, is bound to the proximal segment of a heavy chain leg. Analysis of rat brain and liver complementary DNA clones for LCA and LCB shows that the two light chain classes are closely related. There appear to be several members of each class having deletions of varying length aligned at the same position. A set of ten heptad elements, characteristic of alpha-helical coiled coils, is a striking feature of the central part of each derived amino acid sequence. These observations suggest a model in which the alpha-helical segment mediates binding to clathrin heavy chains and the amino- and carboxyl-terminal segments mediate interactions with other proteins. They also suggest an explanation for the observed tissue-dependent size variation for members of each class. 相似文献
96.
97.
P. N. P. Chow 《Crop Protection》1989,8(6):447-450
Broad-spectrum weed control by use of imazamethabenz (AC 222 293) in herbicide combinations was investigated in the greenhouse. Imazamethabenz at rates ranging from 0·1 to 0·4 kg a.i./ha effectively controlled wild oats (Avena fatua L.). Additional control of redroot pigweed (Amaranthus retroflexus L.) was achieved when imazamethabenz, plus octoxynol surfactant, was applied in combination with MCPA (amine or ester) or commercial MCPA mixtures (bromoxynil/MCPA and cyanazine/MCPA). Only inclusion of propanil/MCPA in the combination reduced wild-oat control by imazamethabenz at the lower rate (0·1 kg/ha). Control of green foxtail (Setaria viridis (L.) Beauv.) was also obtained by use of fenoxaprop-ethyl in combination with imazamethabenz (plus octoxynol). Three-way mixtures of imazamethabenz (or plus octoxynol), MCPA alone or mixture, and fenoxaprop-ethyl may provide practical control of grass and broad-leaved weeds in the field. 相似文献
98.
Connors John Patrick Galletti Christopher S. Chow Winston T. L. 《Landscape Ecology》2013,28(2):271-283
Landscape Ecology - The structure of urban environments is known to alter local climate, in part due to changes in land cover. A growing subset of research focuses specifically on the UHI in terms... 相似文献
99.
The surface morphology of the CO2 laser treated grey cotton fabrics was studied which showed a characteristics sponge-like structure on cotton fibres after
treating with CO2 laser irradiation. The laser treatment parameters ranging from 100 to 150 pixel time and 40 to 70 dot per inch (dpi) were
irradiated on the grey cotton fabrics directly and the degree of physical modifications, such as surface morphology, wettability
and fabric strength, were changed accordingly with various laser treatment parameters. The surface morphology, wettability
and tensile strength of cotton fibre treating with laser were evaluated using different instruments, such as Scanning Electron
Microscope (SEM), contact angle meter and tensile strength machine. In spite of creating a sponge-like structure on fibre
surface after treating with laser, the wettability of the samples was highly improved but the tensile strength was decreased. 相似文献
100.
Pig and herd level prevalence of Toxoplasma gondii in Ontario finisher pigs in 2001, 2003, and 2004 下载免费PDF全文
Zvonimir Poljak Catherine E Dewey Robert M Friendship S Wayne Martin Jette Christensen Davor Ojkic John Wu Eva Chow 《Canadian journal of veterinary research》2008,72(4):303-310
The objective of this study was to estimate the apparent and true prevalence of exposure to Toxoplasma gondii in Ontario finisher pigs. During the study period (2001 to 2004), sera from 6048 pigs were tested with a commercial enzyme-linked immunosorbent assay (ELISA); 103 farms were included 1 to 3 times in the study. True prevalence was estimated using a Bayesian approach. Apparent prevalence at the pig level was 1.59% [95% confidence interval (CI): 0.45, 2.99] in 2001, 0.06% (95% CI: 0.00, 0.46) in 2003, and 0.26% (95% CI: 0.00, 0.82) in 2004. Apparent prevalence at the herd-level was 13.7% (95% CI: 7.5, 22.3) in 2001; 1.25% (95% CI: 0.03, 6.77) in 2003, and 3.75% (95% CI: 0.78, 10.6) in 2004. Similarly, posterior Bayesian estimates of true prevalence at the pig level were 1.7% [95% probability interval (PI): 1.2, 2.2] in 2001, 0.2% (95% PI: 0.04, 0.4) in 2003, and 0.3% (95% PI: 0.1, 0.7) in 2004. At the herd level, posterior estimates of prevalence were 11.6% (95% PI: 7.4, 16.8) in 2001, 0% (95% PI: 0.0, 2.5) in 2003, and 1.2% (95% PI: 0.0, 5.0) in 2004 when a herd cut-point > or = 1 was used. Exposure to T. gondii in finishing pig farms in Ontario appears to be infrequent. 相似文献