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21.
A synchronization treatment was initiated when each of 1227 heifers (four trials) was tailpainted. The tailpaint was sprayed with an aerosol raddle at the end of the treatment period. The heifers were in herds of 20 to 279 animals. Each herd was observed for estrus at selected post treatment intervals. A heifer was considered to be (or to have been) in estrus when the raddle was rubbed off. In three of the trials, animals which had the raddle removed were inseminated at 48h following the end of the synchronization treatment. The tailpaint of an inseminated animal was scored from 0 (less than 10% of the paint remained) to 5 (more than 90% of the paint remained) and was then reraddled with a second color. The detection-insemination sequence was always repeated at 72 and 96h, and sometimes at 120h. Animals which had been previously inseminated, but then had paint scores reduced by at least 2 units were reinseminated 24h later. Over the four trials, 94.5% of the heifers were detected in estrus through the use of the tailpaint and raddle system. The remaining 67 animals included only 10 (0.8%) which had ovulated without being detected in estrus. The reinsemination rate on consecutive days was 11.3% and was highest among animals that had a tailpaint score of 4 or 5 at 48h. The proportion of animals detected in estrus at selected posttreatment intervals varied with the different synchronization treatments used within one herd, or with the same treatment used in different herds. The combination of tailpaint, raddling, tailpaint scoring and reraddling is a simple sequence which can be effectively used to detect estrus among heifers synchronized in research or commercial herds. 相似文献
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Salas-Prato Milagros Tanguay Jean-Francois Lefebvre Yves Wojciechowicz Don Liem H. Heng Barnes David W. Ouellette Ginette Muller-Eberhard Ursula 《In vitro cellular & developmental biology. Plant》1988,24(5):470-470
In Vitro Cellular &; Developmental Biology - Plant - 相似文献
24.
Binding of [3H] leukotriene C4 and D4 to guinea-pig lung sections was charaterised and binding sites were localized by autoradiography. Both leukotrienes bound to guinea-pig lung sections and membranes with high affinity and with similar charateristics to binding in a membrane preparation. Autoradiography revealed that the distribution of LTC4 and D4 binding sites was markedly different. Smooth muscle and epithelium of central and peripheral airways were densely labelled with [3H]LTC4; vascular smooth muscle and alveolar walls were also labelled. With [3H]LTD4, however, there was no detectable labelling of airways or vessels but subtantial labelling of alveolar walls. This lends futher support that LTC4 and LTD4 binding sites differ and may not be identical with functional receptors. 相似文献
25.
Thomas L. Pazdernik Matthew Layton Stanley R. Nelson Fred E. Samson 《Neurochemical research》1992,17(1):11-21
This overview presents data showing that glucose use increases and that excitatory amino acids (i.e., glutamate, aspartate), taurine and ascorbate increase in the extracellular fluid during seizures. During the cellular hyperactive state taurine appears to serve as an osmoregulator and ascorbate may serve as either an antioxidant or as a pro-oxidant. Finally, a unifying hypothesis is given for seizure-induced brain damage. This unifying hypothesis states that during seizures there is a release of excitatory amino acids which act on glutamatergic receptors, increasing neuronal activity and thereby increasing glucose use. This hyperactivity of cells causes an influx, of calcium (i.e. calcium stress) and water movements (i.e., osmotic stress) into the cells that culminate in brain damage mediated by reactive oxygen species.Special issue dedicated to Dr. Frederick E. Samson 相似文献
26.
A sampler for collection of interstitial water from wetland sediments is described. It differs from other sampling devices because it does not have to be filled with solution to facilitate diffusion, it does not have to be removed from the wetland to collect samples, and it can be used to draw repeated samples over time from identical locations. The device facilitates in situ measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH in wetland sediments. The device has application in ecological investigations of sediment-borne wildlife diseases, studies of benthic invertebrates, measurement of nutrient exchange, and other aspects of wetland ecology. 相似文献
27.
This article examines "wire configuration coding" as used to estimate relative residential AC magnetic field exposure in epidemiological studies--and the need to alter such coding for time or locations other than those in which the code was developed. Effects of different secondary wire practices are particularly examined. 相似文献
28.
Michele Solem Angela Helmrich Paul Collodi David Barnes 《Molecular and cellular biochemistry》1991,100(2):141-149
Summary Human S-protein is a serum glycoprotein that binds and inhibits the activated complement complex, mediates coagulation through interaction with antithrombin III and plasminogen activator inhibitor I, and also functions as a cell adhesion protein through interactions with extracellular matrix and cell plasma membranes. A full length cDNA clone for human S-protein was isolated from a lambda gt11 cDNA library of mRNA from the HepG2 hepatocellular carcinoma cell line using mixed oligonucleotide sequences predicted from the amino-terminal amino acid sequence of human S-protein. The cDNA clone in lambda was subcloned into pUC18 for Southern and Northern blot experiments. Hybridization with radiolabeled human S-protein cDNA revealed a single copy gene encoding S-protein in human and mouse genomic DNA. In addition, the S-protein gene was detected in monkey, rat, dog, cow and rabbit genomic DNA. A 1.7 Kb mRNA for S-protein was detected in RNA from human liver and from the PLC/PRF5 human hepatoma cell line. No S-protein mRNA was detected in mRNA from human lung, placenta, or leukocytes or in total RNA from cultured human embryonal rhabdomyosarcoma (RD cell line) or cultured human fibroblasts from embryonic lung (IMR90 cell line) and neonatal foreskin. A 1.6 Kb mRNA for S-protein was detected in mRNA from mouse liver and brain. No S-protein mRNA was detected in mRNA from mouse skeletal muscle, kidney, heart or testis. 相似文献
29.
30.
Cloning and expression of a cDNA encoding a catalytically active fragment of calf thymus DNA polymerase alpha 总被引:2,自引:0,他引:2
K Foster K Lüthi-Steinmann M Barnes G McMaster E Ferrari K Eliassen N Khan N Brown U Hübscher 《Biochemical and biophysical research communications》1986,140(1):21-27
A calf thymus cDNA expression library was constructed in the EcoRI site of lambda gt11 and probed with an antibody raised against calf thymus DNA polymerase alpha. Three classes of antibody-reactive clones were isolated. The largest class carried a 1.9 kilobase calf cDNA insert and expressed a 165-175 kilodalton beta-galactosidase:calf fusion protein which displayed DNA polymerase activity. The characteristic responses of the polymerase activity to alpha-specific inhibitors and antibodies identified the 1.9 kilobase cDNA as a sequence specifically derived from the structural gene encoding the pol alpha catalytic core. 相似文献