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991.
H Suzuki N D Christofides T E Adrian M Chretien N G Seidah J M Polak S R Bloom 《Regulatory peptides》1985,12(4):289-296
The developmental profile of the concentration of a novel pituitary protein (7B2) was studied immunochemically in the human gastrointestinal tract from 12 weeks of gestation to 4 months after birth and was compared to the distribution in the adult. 7B2-like immunoreactivity (IR-7B2) was detected in all segments studied, but no gross changes were seen through fetal life. At term higher concentrations of IR-7B2 were found in the duodenum and the antrum, which is similar to the distribution of adult man. Gel permeation chromatography revealed that the main peak of 7B2 immunoreactivity in the fetal intestinal extract eluted with a Kav of 0.3. Similar elution profiles were also observed in extracts of human adult intestine. 相似文献
992.
In a recent publication (Plant Molecular Biology 16: 547–565 (1991)) Showalter et al. described the isolation and initial characterization of fifteen extensin and extensin-like tomato cDNAs. These cDNAs were determined to fall into five distinct classes; class I and II clones encoded extensins, class III and V clones encoded glycine-rich proteins (GRPs), and class IV clones encoded a portion of a GRP sequence on one DNA strand and a portion of an extensin sequence on the other DNA strand. In this publication, a more detailed analysis of the expression of these cDNA classes was performed with respect to wounding in various tomato organs, development, kinetics and systemic extent of the wound response, ethylene treatment, abscisic acid (ABA) treatment, and drought stress by using RNA gel blot hybridizations. In general, extensin gene expression was readily detected in stems and roots, but not in leaves. With both class I and II extensin cDNA probes, wound-induced accumulation of mRNA in stems was first detected between 4 and 8 h after wounding with maximal accumulation occurring after 12 h. Moreover, these extensin wound responses were detected locally at the wound site but not systemically. Expression of the class III GRP was largely limited to wounded stem tissue. Initial detection and maximal accumulation of the class III GRP mRNA was similar to the extensins mRNAs; however, this GRP wound response occurred both locally and systemically. Additionally, abscisic acid treatment and drought stress resulted in the marked accumulation of the class III GRP mRNA in tomato stems, but did not alter the expression of the other cDNA classes. In contrast, expression of the class V GRP occurred in stems and roots and to a lesser extent in leaves and decreased in response to wounding over a 24 h time period. The class V GRP wound response was further characterized by an early, transient accumulation of mRNA occurring 2–4 h after wounding in stems and by its local nature. 相似文献
993.
Infusion of somatostatin reduced the symptoms of the early dumping syndrome after oral glucose was given and also reduced the associated tachycardia and rise in packed cell volume. It inhibited the secretion of enteroglucagon, neurotensin, and vasoactive intestinal polypeptide, which are raised in patients with the dumping syndrome and may have an aetiological role. It also prevented the reactive hypoglycaemia of late dumping by inhibiting the release of gastric inhibitory polypeptide and insulin. Somatostatin, possibly through its inhibitory effects on hormonal secretion, may have a role in the management of patients with the early and late dumping syndrome. 相似文献
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997.
Malcolm Parker Lindy Willmott Ben White Gail Williams Colleen Cartwright 《Journal of bioethical inquiry》2018,15(1):101-109
Over several decades, ethics and law have been applied to medical education and practice in a way that reflects the continuation during the twentieth century of the strong distinction between facts and values. We explain the development of applied ethics and applied medical law and report selected results that reflect this applied model from an empirical project examining doctors’ decisions on withdrawing/withholding treatment from patients who lack decision-making capacity. The model is critiqued, and an alternative “constitutive” model is supported on the basis that medicine, medical law, and medical ethics exemplify the inevitable entanglement of facts and values. The model requires that ethics and law be taught across the medical education curriculum and integrated with the basic and clinical sciences and that they be perceived as an integral component of medical evidence and practice. Law, in particular, would rank as equal in normative authority to the relevant clinical scientific “facts” of the case, with graduating doctors having as strong a basic command of each category as the other. The normalization of legal knowledge as part of the clinician’s evidence base to be utilized in practice may provide adequate consolation for clinicians who may initially resent further perceived incursions on their traditional independence and discretion. 相似文献
998.
Hannah H. E. Van Zanten Mario Herrero Ollie Van Hal Elin Röös Adrian Muller Tara Garnett Pierre J. Gerber Christian Schader Imke J. M. De Boer 《Global Change Biology》2018,24(9):4185-4194
The need for more sustainable production and consumption of animal source food (ASF) is central to the achievement of the sustainable development goals: within this context, wise use of land is a core challenge and concern. A key question in feeding the future world is: how much ASF should we eat? We demonstrate that livestock raised under the circular economy concept could provide a significant, nonnegligible part (9–23 g/per capita) of our daily protein needs (~50–60 g/per capita). This livestock then would not consume human‐edible biomass, such as grains, but mainly convert leftovers from arable land and grass resources into valuable food, implying that production of livestock feed is largely decoupled from arable land. The availability of these biomass streams for livestock then determines the boundaries for livestock production and consumption. Under this concept, the competition for land for feed or food would be minimized and compared to no ASF, including some ASF in the human diet could free up about one quarter of global arable land. Our results also demonstrate that restricted growth in consumption of ASF in Africa and Asia would be feasible under these boundary conditions, while reductions in the rest of the world would be necessary to meet land use sustainability criteria. Managing this expansion and contraction of future consumption of ASF is essential for achieving sustainable nutrition security. 相似文献
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1000.
Elizabeth A. Hamman Scott A. McKinley Adrian C. Stier Craig W. Osenberg 《Theoretical Ecology》2018,11(1):111-127
Variation in the density of organisms among habitat patches is often attributed to variation in inherent patch properties. For example, higher quality patches might have higher densities because they attract more colonists or confer better post-colonization survival. However, variation in occupant density can also be driven by landscape configuration if neighboring patches draw potential colonists away from the focal habitat (a phenomenon we call propagule redirection). Here, we develop and analyze a stochastic model to quantify the role of landscape configuration and propagule redirection on occupant density patterns. We model a system with a dispersive larval stage and a sedentary adult stage. The model includes sensing and decision-making in the colonization stage and density-dependent mortality (a proxy for patch quality) in the post-colonization stage. We demonstrate that spatial variation in colonization is retained when the supply of colonists is not too high, post-colonization density-dependent survival is not too strong, and colonization events are not too frequent. Using a reef fish system, we show that the spatial variation produced by propagule redirection is comparable to spatial variation expected when patch quality varies. Thus, variation in density arising from the spatial patterning of otherwise identical habitat can play an important role in shaping long-term spatial patterns of organisms occupying patchy habitats. Propagule redirection is a potentially powerful mechanism by which landscape configuration can drive variation in occupant densities, and may therefore offer new insights into how populations may shift as landscapes change in response to natural and anthropogenic forces. 相似文献