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(上接2012年第3期)
(3)减阻设计方案3评估
第三种设计方案将减阻物放在相邻的两个侧面上.它的响应和设计方案1相同并且当网箱一开始运行时就沉入水中.当水速达到32厘米/秒时停止测试,因为此时可以观察到网箱沉至离水面7.3米一下(满标度),而且速度再增大时将撞击测试槽底部了(图28). 相似文献
3.
When administered by a variety of routes decamethrin (NRDC 161) produced a clearly defined sequence of symptoms in the rat. These involved, progressively, chewing, salivation, pawing, choreoathetosis, tonic seizures, and death. Although animals showing tonic seizures almost invariably died, the choreoathetotic symptoms were largely reversible. Animals maintained adequate blood-gas values and arterial pressure until choreoathetosis was well advanced. Electroencephalograph records showed generalized spike and wave discharges during choreoathetosis and auditory or somatosensory-evoked spike discharges prior to choreoathetosis. Symptoms were partially antagonized by atropine. It is suggested that decamethrin-induced choreoathetosis may provide a useful model for the study of related human disorders. 相似文献
4.
Giorgio Gambino Jeannette Bondaz Ivana Gribaudo 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):397-404
The distribution of some grapevine viruses in flower explants, embryogenic and non-embryogenic calli, single somatic embryos
and plants regenerated from embryogenic cultures was investigated by RT-PCR and ELISA. Immature anthers and ovaries of the
cultivars Grignolino infected by GRSPaV, GLRaV-1 and GVA, Müller-Thurgau infected by GRSPaV and GLRaV-3 and Bosco infected
by GRSPaV were cultivated on media inducing indirect somatic embryogenesis. Viruses were detected both in anthers and ovaries.
Four months after culture initiation 65.6% of tested calli were infected by at least one virus; high percentages of virus
infection were found in calli originating from ovaries. No virus was detected in calli tested 8 months after culture initiation,
as well as in single somatic embryos or in embryo-derived plantlets. Somatic embryogenesis confirmed its effectiveness in
eliminating phloem-limited grapevine viruses. Regeneration of RT-PCR negative plantlets occurred even when at least a sector
of the callus was still infected: the mechanism whereby somatic embryos are freed of some viruses could be related to the
rapid proliferation of embryogenic cells within the callus or to the origin of the embryogenic callus from virus-free cells
within the original explant. 相似文献
5.
A new kaurane diterpene dimer, 15-oxozoapatlin-13alpha-yl-10'alpha,16'alpha-dihydroxy-9'alpha-methyl-20'-nor-kauran-19'-oic acid gamma-lactone-17'-oate (1), together with the known 13-hydroxy-15-oxozoapatlin (2), 10alpha,13alpha,16alpha,17-tetrahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (3), 2alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid (19,10)-lactone (4), 3alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (5), and 1beta,16alpha,17-trihydroxy-ent-kaurane (6) were isolated from the leaves of Parinari campestris and identified on the basis of detailed spectral analysis, including 2D NMR spectrometry and ESI-MS. 相似文献
6.
Mariëlle M.C. Goossens Ad Rijnberk Jan A. Mol Jeannette Wolfswinkel George Voorhout 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(5):361-365
Central diabetes insipidus was diagnosed by vasopressin measurements during hypertonic stimulation in a 9-year-old male giant Schnauzer with polyuria and polydipsia. The impaired release of vasopressin was believed to be caused by a large pituitary tumor, which was visualized by computed tomography. Studies of the function of the anterior lobe and the pars intermedia of the pituitary gland were conducted, and high concentrations of ACTH and α-melanotrophic hormone (α-MSH) were found without concomitant hyperadrenocorticism. Studies of the molecular size of the immunoreactive ACTH in plasma by gel filtration revealed that most of the circulating immunoreactivity was not ACTH but its precursor pro-opiomelanocortin (POMC) and low-molecular-weight POMC-derived peptides. The pituitary tumor of this dog probably originated from melanotrophic cells of the pars intermedia. The sensitivity of the pituitary-adrenocortical system for the suppressive effect of dexamethasone was unaffected. 相似文献
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Jeannette S. Bayuelo-Jiménez Takashi Muraoka Eulogio de la Cruz-Torres Esperanza Quintero-Ponce Lydia C. Paredes-Gutiérrez Mohammad Zaman 《Soil Use and Management》2020,36(2):240-249
Land-use change from forest to agriculture in the volcanic ash-derived soils of Mexico has increased over recent decades. It is likely that land uses and management practices, particularly fertilizer use have affected phosphorus (P) distribution and availability. The objective of this study was to evaluate the effects of land-use types (native forest and maize mono-cropping), and the related P addition, on the forms and distribution of soil P and their isotopic exchangeability. An Andisol, sampled from a cropping site, along with the contiguous area under native forest was treated with 32P-labelled potassium phosphate (KH232PO4). The soil samples were extracted after incubation times of 7, 21, 35 and 49 days. Phosphorus content and 32P recovery in fractions sequentially extracted were assessed for each incubation time. Total soil P was dominated by inorganic fractions (79 to 86%) in both land-use types. Resin-Pi, bicarbonate extractable inorganic P (Bic-Pi) and sodium hydroxide extractable inorganic P (NaOH0.1-Pi) were all raised with P addition. However, the proportion of organic P fraction was reduced under cropped soil. The recovery of 32P in soils with P addition indicates that resin-Pi, Bic-Pi and NaOH0.1-Pi comprised nearly all the exchangeable P. In native soils with no P addition, more than 19% of the 32P was recovered in Bic-Po and NaOH0.1-Po forms. This finding indicates that organic P cycling is crucial when soil Pi reserves are presented in an inadequate amount. Ecologically based management has to be designed for replenishment and succeeding maintenance of soil organic P compounds to increase sustainable agricultural production. 相似文献
9.
McDonald J 《Journal of veterinary medical education》2008,35(2):207-211
The American public is concerned about food safety, and there is a growing realization that we are ill equipped to handle major food-borne illness outbreaks and bioterrorism. Since veterinary medicine plays an important role in assuring the safety of our nation's food supply, we would like to present to veterinary and public health educators a newly emerging resource for food-safety educational materials. This article describes an integrative collaborative approach for the creation and dissemination of engaging food-safety teaching resources for veterinary faculty. This USDA-funded project, Design to Dissemination: Developing Materials and Repository for Integrative Veterinary Food Safety Education, involves expert teachers in diverse fields and from many veterinary schools. The purpose of the project is to create materials that teach students food safety from farm to fork, and it offers teachers clinically relevant teaching resources that are difficult to create or locate. The educational materials are being created as smaller "building blocks" of content, commonly referred to as "learning objects" (LOs), focused on individual learning objectives. These learning objects are placed in the Veterinary Food Safety Education Learning Object Repository, where they are catalogued, stored, and kept accessible and where faculty can search, evaluate, and download teaching materials to use in their courses. In this way the learning objects can be more easily shared and reused or repurposed for other courses and applications. With this article we hope to excite faculty in veterinary schools and public-health programs and encourage them to use the repository and participate in piloting the educational materials. 相似文献