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31.
Estrous synchronization and establishment of pregnancy in bovine embryo transfer recipients 总被引:1,自引:0,他引:1
Characteristics of donors, embryos, recipients, and transfer procedures were examined for relationships with establishment of pregnancy. Data were from records of 1202 embryos transferred by the professional staff of a large embryo transfer company. Average pregnancy rate was 74.6%. Variables affecting establishment of pregnancy were service sire, embryo quality, stage of estrous cycle in recipient, quadratic effect of synchrony, and transfer quality. Because the direct or indirect effect of sire must be established at conception, these data demonstrate a latent effect of sire on pregnancy. One would expect the highest pregnancy rate among excellent quality embryos transferred with no delays or complications into recipients that had displayed estrus at the same time or prior to the donor yet were relatively early in their estrous cycles. There also was a tendency for pregnancy rate to decrease with advancing maturity of the embryo. 相似文献
32.
An investigation is made into the ways proof planning can enhance the capability of a rule based prover for the theory of integration. The integrals are of the Riemann type and are defined in a way to maximize the theorem proving methods of predicate calculus. Approximately fifty theorems have been proved and several examples are discussed. A major shortcoming was found to be the inability of the system to work with or produce a proof plan. As a result, a planning scheme based on the idea of subgoals or milestones was considered. With user defined plans, there was a substantial increase in performance and capability of the system and, in some cases, proofs which were previously unsuccessful were completed. 相似文献
33.
Subjected research on Ivey's (1971) microcounseling program to a comprehensive meta-analytic review. A multistage sampling procedure resulted in the identification of 81 admissible studies. Glass's (1976) effect size (ES) statistic was used to estimate average effects for each study and across all studies, and the relation between ES and the sampling distribution of several important methodological and substantive characteristics was assessed. The most conservative overall ES statistic fell in the large-effect category. ESs were influenced differentially by the populations from which Ss were drawn and by the type of client the Ss interviewed when data for ratings on dependent measures were acquired. There was some evidence that the dependent measures used in microcounseling research are limited, which led to a conclusion that research on the teaching of more complex skills may be delayed. The microcounseling program has made a contribution to counseling training and may have pointed the way to new training models. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
The extraction of nitrogenous material from Brewers' spent grain (BSG) by solvents (water, sodium chloride solution, aqueous alcohol, acidic and alkaline solutions) commonly used to extract cereal proteins, resulted in the relatively low (0·2 to 8·5%) recovery of the total nitrogen. The recovery of nitrogenous material by the use of aqueous alkaline solutions was increased from 3–4% to 41% when the BSG was subjected to cellulase incubation prior to extraction. Approximately 75% of the nitrogen was solubilized with trifluoracetic acid. Detergent solutions (acid, neutral) solubilized more than 80% of the total nitrogen of the BSG. The low solubility of the nitrogenous constituents by conventional protein solvents could be the result of association between cellulosic material and protein. 相似文献
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Two experiments addressed the issue of whether endorsement of a position by a numerical majority or a minority leads to greater scrutiny of the information presented in a persuasive message. In Exp 1, a counterattitudinal position was endorsed by a majority or a minority and was supported by strong or weak arguments. Argument quality had a larger impact on attitudes with majority than with minority endorsement. In Exp 2, a proattitudinal or a counterattitudinal message was endorsed by a majority or a minority and was supported by strong or weak arguments. When the source and message position were unexpected (i.e., majority-counter and minority-pro messages), argument quality had a larger impact on attitudes than when the source and message position were expected (i.e., majority-pro and minority-counter messages). Thus, either majority or minority endorsement can enhance message scrutiny if the source-position pairing is surprising. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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UR Juergens SC Christiansen DD Stevenson BL Zuraw 《Canadian Metallurgical Quarterly》1995,96(2):148-156
Aspirin-sensitive patients may be desensitized through a graded series of exposures to aspirin. We investigated the underlying mechanism of aspirin desensitization by measuring the release of leukotrienes B4 and C4 from calcium ionophore-stimulated peripheral blood monocytes. Compared with monocytes from normal volunteers (n = 5), monocytes from patients with aspirin-sensitive asthma (n = 10) released increased amounts of thromboxane B2 (1060 +/- 245 pg/ml vs 456 +/- 62 pg/ml), leukotriene B4 (861 +/- 139 pg/ml vs 341 +/- 44 pg/ml), and leukotriene C4 (147 +/- 31 pg/ml vs 56 +/- 6 pg/ml) at baseline. After aspirin desensitization, thromboxane B2 release was almost completely suppressed in both groups. Leukotriene B4 release was significantly decreased in the aspirin-sensitive group (484 +/- 85 pg/ml) but not in the normal subject group (466 +/- 55 pg/ml). The need for prednisone decreased significantly after patients were desensitized to aspirin (10.4 +/- 2.2 mg/day to 1.6 +/- 2.8 mg/day). These results demonstrate that desensitization to aspirin results in decreased monocyte leukotriene B4 release. On the basis of the bronchospastic and inflammatory potential of leukotrienes, the decrease in leukotriene release may contribute to the clinical improvement seen after aspirin desensitization. 相似文献
40.
We employed an anatomically realistic three-dimensional finite-element model to explore several biomechanical variables involved in coring or bone-grafting of a segmentally necrotic femoral head. The mechanical efficacy of several variants of these procedures was indexed in terms of their alteration of the stress:strength ratio in at-risk necrotic cancellous bone. For coring alone, the associated structural compromise was generally modest, provided that the tract did not extend near the subchondral plate. Cortical bone-grafting was potentially of great structural benefit for femoral heads in which the graft penetrated deeply into the superocentral or lateral aspect of the lesion, ideally with abutment against the subchondral plate. By contrast, central or lateral grafts that stopped well short of the subchondral plate were contraindicated biomechanically because they caused marked elevations in stress on the necrotic cancellous bone. Calculated levels of stress were relatively insensitive to variations in the diameter of the graft. 相似文献