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排序方式: 共有227条查询结果,搜索用时 15 毫秒
221.
G Gábor F Tóth L Ózsvári Zs Abonyi-Tóth RG Sasser 《Reproduction in domestic animals》2007,42(6):633-636
Over a 25-month period 8118 blood samples were assayed for the presence of the serum pregnancy specific-protein B (PSPB) and progesterone (P4) concentrations on three Hungarian large-scale dairy farms. Pregnancy (n = 4085) was checked by BioPRYN assay at 30-36 days post-insemination (PI). Samples from all cows that tested not pregnant and from cows with an optical density (OD) reading in the BioPRYN test that was between 0% and 30% above the cutoff OD value were tested for serum P4 concentration. According to serum P4 concentration, cows were assigned to three categories: high (>4 ng/ml), medium (2-4 ng/ml) and low (<2 ng/ml) serum progesterone. The authors predicted a presumed (low) or possible (medium) late embryonic loss (LEL) or maintenance of the pregnancy (high). A total of 710 LELs were detected (17.4%) and 31.8% of them were predicted because of a low OD value at 30-36 days after insemination. Lower PSPB serum level significantly refers for LEL (p < 0.0001). The prediction rate for the true embryonic loss was 31.8% when OD cutoff from 0% to + 30% of cutoff was examined while it was 62.5% when the threshold was OD cutoff of 0% to 10% of cutoff. The authors conclude that BioPRYN was useful for prediction of a part of LEL in dairy cows and serum P4 concentration in these cows related to the rate of LEL. 相似文献
222.
Cyanide-free Net-caught Fish for the Marine Aquarium Trade 总被引:1,自引:0,他引:1
Peter J. Rubec Ferdinand Cruz Vaughan Pratt Richard Oellers Brian McCullough Frank Lallo 《Aquarium Sciences and Conservation》2001,3(1-3):37-51
The International Marinelife Alliance (IMA) has been training collectors in the Philippines and Indonesia to use barrier-nets rather than sodium cyanide to capture marine-aquarium fish. Despite the training, collectors have been slow to switch to using nets because they can earn more using cyanide. A new Philippine export company has agreed to pay the collectors more for net-caught fish and to adhere to standards being set by the USA-based Marine Aquarium Council. The IMA is monitoring the collectors and conducting cyanide testing to certify that the fish are net-caught and totally cyanide-free. Clearance certificates now accompany shipments of these marine-aquarium fish being shipped to wholesalers and retailers associated with the American Marine Dealers Association (AMDA) situated in the USA and Canada. AMDA members are being surveyed to assess whether the net-caught fish are more cost competitive compared to cyanide-caught fish for the marine ornamental fish trade because of reduced mortality through the chain from reef to retailer. 相似文献
223.
The tepary bean (Phaseolus acutifolius A. Gray) is a desirable genetic resource for incorporation of improved disease, pest, and stress resistance into common bean (P. vulgaris L.). Reproductive barriers separate the two species and the degree to which tepary genes may be introgressed into the common bean genome has not been well described. Greenhouse studies of gene introgression through recurrent back-crossing to common bean were performed using two first backcross (BC1) and nine second backcross (BC2) populations. The truncate primary leaf characteristic of tepary bean was readily observed but the short primary leaf petiole and narrow bract tepary traits were infrequently observed in both BC1 and BC2 populations. In one BC, population high frequencies of adaxial stomata (characteristic of P. acutifolius) and the presence of a 30 kD cotyledon polypeptide from P. acutifolius were also observed; however, a diapho-rase isozyme from P. acutifolius appeared to be eliminated from BC1 progeny at a high rate whereas 6-phosphogluconate dehydrogenase alleles appeared to be transmitted normally. The expression of tepary primary leaf truncate morphology and bract width were correlated with decreased fertility in one of the two BC1 populations. Given suitable parental genotypes and population sizes it should be possible to transfer genes from P. acutifolius to P. vulgaris, especially in regions of the genome which are not associated with inviability or sterility. It will be difficult to transfer factors from certain regions of the tepary genome which are preferentially eliminated during introgression. 相似文献
224.
Pfanstiel JF Champagne BB Majewsi WA Plusquellic DF Pratt DW 《Science (New York, N.Y.)》1989,245(4919):736-738
Band 1 in the jet-cooled one-photon S(1) <-- S(0) fluorescence excitation spectrum of all-trans-1,4-diphenyl-1,3-butadiene has been rotationally resolved with a molecular beam laser spectrometer. Both the orientation of the optical transition moment and the rotational constants of the two vibronic levels have been measured. The molecule shows no evidence of being significantly distorted from a C(24) geometry when it is low in the vibrational manifolds of either of the two electronic states. 相似文献
225.
226.
Hayward MA Cussen EJ Claridge JB Bieringer M Rosseinsky MJ Kiely CJ Blundell SJ Marshall IM Pratt FL 《Science (New York, N.Y.)》2002,295(5561):1882-1884
We present the synthesis and structural characterization of a transition metal oxide hydride, LaSrCoO3H0.7, which adopts an unprecedented structure in which oxide chains are bridged by hydride anions to form a two-dimensional extended network. The metal centers are strongly coupled by their bonding with both oxide and hydride ligands to produce magnetic ordering at temperatures up to at least 350 kelvin. The synthetic route is sufficiently general to allow the prediction of a new class of transition metal--containing electronic and magnetic materials. 相似文献
227.
RG Cashmore TR Harcourt-Brown PM Freeman ND Jeffery N Granger 《Australian veterinary journal》2009,87(1-2):45-50
Three dogs were referred to The Queen's Veterinary School Hospital at University of Cambridge for chronic behavioural or locomotor disorders associated with pain. All three had been unsuccessfully treated with conventional analgesics, including non-steroidal anti-inflammatory drugs, glucocorticoids and opiate agonists, prior to referral, with minimal or no response. They were investigated by neurological examination plus conventional ancillary diagnostic tests and therapeutic drug trials. Ruling out other causes of pain and applying previously well-described criteria, each case was diagnosed as consistent with neuropathic pain, a poorly recognised condition in domestic dogs. Treatment with the tricyclic antidepressant drug, amitriptyline, or the antiepileptic drug, gabapentin, resulted in either a dramatic improvement or full resolution of clinical signs in all cases. 相似文献