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131.
Effect of fixation time on measurement of 2''-deoxyribonucleoside 5''-triphosphate pools in the rat embyro. 下载免费PDF全文
Values for the concentrations of deoxyribonucleoside triphosphates in rat embryos on day 12 of gestation, determined by high-pressure liquid chromatography, were artifactually two to three times as high in embryos fixed by cooling in ice/water followed by freezing on solid CO2, in 20s, as in those more rapidly/fixed in liquid N2, in 1 s. 相似文献
132.
M. T. Scott 《Cancer immunology, immunotherapy : CII》1979,6(2):107-112
Summary A CBA mouse fibrosarcoma (M4) growing as a solid tumour was treated with a single high dose (200 mg/kg) of cyclophosphamide (CY) followed by C. parvum (CP) immunotherapy. The optimal time for the administration of both nonspecific (CP IV) and active specific (SC CP-irradiated tumour cell mixtures) immunotherapy after CY was 4 days, compared with 1, 8, or 12 days. Optimal combinations of CY and CP were synergistic in that they provided a stronger antitumour effect than the sum of the individual effects of the two agents. In keeping with the finding that a 4-day interval between CY and CP was better than only 1 day, studies in normal mice show that when CP is given early during the suppressive phase of CY the onset of both specific and nonspecific antitumour effects are delayed. CY increased the susceptibility of mice to the toxic effects of a subsequent high systemic dose of CP. 相似文献
133.
134.
P V Scott 《BMJ (Clinical research ed.)》1979,2(6205):1663-1664
135.
136.
Tj. B. van Wimersma Greidanus P. J. Lowry A. P. Scott Lesley H. Rees D. De Wied 《Hormones and behavior》1975,6(4):319-327
Recently purified melanocyte-stimulating hormones (MSH's) from dogfish pituitary tissue were tested on extinction of a conditioned avoidance response (CAR). Corticotrophin like intermediate lobe peptides (CLIP's) from dogfish and porcine origin were tested for an effect on avoidance extinction as well. All peptides appeared to delay extinction of the CAR.The results suggest that the pituitary contains various peptides which influence adaptive behavior. The observation that MSH is more potent in delaying extinction of the CAR then CLIP leads to the conclusion that the behavioral active sequence of the ACTH molecules is located in the N terminal part rather than in the C terminal part of the polypetide. 相似文献
137.
G L Miller R L Kline J B Scott F J Haddy G J Grega 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,149(3):581-586
The aim of this study was to determine if edema develops in the canine forelimb after relief of prolonged ischemia. Two hours of ischemia was induced either by interrupting brachial artery inflow in collateral-free innervated, naturally and constantly perfused preparations or by applying a pressure cuff in intact preparations. Changes in extravascular fluid volume were inferred from changes in limb weight. Relief of ischemia produced a transient 1.7% increase in weight in the collateral-free, naturally perfused preparation but had no effect on weight in the collateral-free, constantly perfused or intact preparations. Skin lymph flow failed to change significantly and total lymph protein concentration increased only slightly. Thus, relief of 2 hr of ischemia does not produce marked edema or a large increase in microvascular permeability to plasma proteins in the dog forelimb. 相似文献
138.
139.
Christopher G. Laine Harvey M. Scott Angela M. Arenas-Gamboa 《PLoS neglected tropical diseases》2022,16(5)
BackgroundFor decades, human brucellosis has been recognized worldwide as a significant cause of morbidity, yet the annual incidence of this disease remains unknown. We analyzed this frequency, using international reports (2005–2019), identifying information gaps, and distinguishing a possible path forward.Methodology/Principal findingsA novel approach to estimating the incidence of this disease was explored. We utilized annual health data extracted from the World Organization for Animal Health (OIE)–World Animal Health Information System (WAHIS) database, assessing the dataset completeness and representativeness of the data for the world population. Additionally, we assessed the reported country level human brucellosis case counts and the factors that influenced the observed changes over time. Our analysis revealed incomplete and unrepresentative information, preventing the estimation of annual human brucellosis case incidence at the global level. In the OIE-WAHIS database, only 48.4% of the required reports have been submitted as of 2019, with approximately 47.3% of the world population represented. Additionally, geographic regions were disproportionate in completeness, representativeness, and actual reported case counts. Africa and Asia constituted the majority of reported cases, while simultaneously submitting the lowest percentage of reports as well as covering the lowest percentage of their populations within those reports, when compared to the rest of the world.Conclusions/SignificanceThe global annual frequency of human brucellosis cases remains elusive. Furthermore, there exists great heterogeneity in diagnostic, surveillance, and reporting systems worldwide, calling into question the validity of available information. This study reveals that the Neglected Zoonotic Disease priority status for brucellosis should be restored. 相似文献
140.
Felix Molter Armin W. Thomas Scott A. Huettel Hauke R. Heekeren Peter N. C. Mohr 《PLoS computational biology》2022,18(7)
Choices are influenced by gaze allocation during deliberation, so that fixating an alternative longer leads to increased probability of choosing it. Gaze-dependent evidence accumulation provides a parsimonious account of choices, response times and gaze-behaviour in many simple decision scenarios. Here, we test whether this framework can also predict more complex context-dependent patterns of choice in a three-alternative risky choice task, where choices and eye movements were subject to attraction and compromise effects. Choices were best described by a gaze-dependent evidence accumulation model, where subjective values of alternatives are discounted while not fixated. Finally, we performed a systematic search over a large model space, allowing us to evaluate the relative contribution of different forms of gaze-dependence and additional mechanisms previously not considered by gaze-dependent accumulation models. Gaze-dependence remained the most important mechanism, but participants with strong attraction effects employed an additional similarity-dependent inhibition mechanism found in other models of multi-alternative multi-attribute choice. 相似文献