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报道了豆科Leguminosae昆仑岩黄耆Hedysarum krassnovii B.Fedtsch.在中国的分布。昆仑岩黄耆与近缘种红花岩黄耆H.multijugum Maxim.形态易混淆,但以其小叶3-9×3-7mm;旗瓣倒卵形,顶端凹陷约2mm深;翼瓣狭披针形;龙骨瓣近半圆形或矩圆形;花萼二唇彤;荚果具1-2节荚等性状易于区分。另外,此二种的物候期、生境及地理分布亦有区别。 相似文献
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Alzheimer’s Disease (AD) is characterized by progressive neurodegeneration and cognitive impairment. Synaptic dysfunction is an established early symptom, which correlates strongly with cognitive decline, and is hypothesised to mediate the diverse neuronal network abnormalities observed in AD. However, how synaptic dysfunction contributes to network pathology and cognitive impairment in AD remains elusive. Here, we present a grid-cell-to-place-cell transformation model of long-term CA1 place cell dynamics to interrogate the effect of synaptic loss on network function and environmental representation. Synapse loss modelled after experimental observations in the APP/PS1 mouse model was found to induce firing rate alterations and place cell abnormalities that have previously been observed in AD mouse models, including enlarged place fields and lower across-session stability of place fields. Our results support the hypothesis that synaptic dysfunction underlies cognitive deficits, and demonstrate how impaired environmental representation may arise in the early stages of AD. We further propose that dysfunction of excitatory and inhibitory inputs to CA1 pyramidal cells may cause distinct impairments in place cell function, namely reduced stability and place map resolution. 相似文献
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Soumya Ivaturi Catherine J. Wooten Maikhanh D. Nguyen Gene C. Ness Dayami Lopez 《Biochemical and biophysical research communications》2014
Several findings suggest that the low-density lipoprotein (LDL) receptor may internalize different lipoprotein particles via diverse pathways. Using a combination of discontinuous sucrose gradients and Triton solubilization studies, we demonstrated that the LDL receptor could be located simultaneously in clathrin-coated pits and caveolae in rat and human liver and in human hepatocyte-like C3A cells. Treatment with the cholesterol biosynthesis inhibitor, zaragozic acid A, shifted the distribution of the LDL receptor to clathrin containing fractions, whereas treatment with cholesterol or LDL shifted the receptor distribution towards caveolin-1 containing fractions. The LDL-dependent shift of the LDL receptor to caveolae coincided with a reduction in internalization of Bodipy-LDL. Redistribution within plasma membrane microdomains in response to specific treatments resulting in changes in LDL receptor function represents a novel paradigm that could be exploited in the development of a new class of therapeutic drugs. 相似文献
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Bradley J. Van Sickle Jill Simmons Randon Hall Miranda Raines Kate Ness Anna Spagnoli 《Cytokine》2009,48(3):290-294
Background: A dysregulated growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis is well-recognized in children and adolescents with type 1 diabetes mellitus (T1DM). Decreased IGF-1 levels can also be found in chronic inflammatory diseases, while hyperglycemia promotes inflammatory cytokine production. Therefore, inflammatory cytokines may link poor metabolic control with GH/IGF-1 axis changes. This study examined the relationship between serum inflammatory cytokines and IGF-1 in adolescents (age 13–18) with TIDM in chronic poor (n = 17) or favorable (n = 19) glucose control. Poor control (PC) was defined as 3, consistent HbA1C > 9% during the previous 2 years, while favorable control (FC) was consistent levels of HbA1C < 9%. Results: HbA1C (FC: 7.5 ± 0.6%; PC: 10.5 ± 0.9%, p < 0.001) and interleukin (IL)-8 (FC: 3.7 ± 4.0 pg/ml; PC: 7.4 ± 4.3 pg/ml, p = 0.01) were increased and IGF-1 (FC: 536.5 ± 164.3 ng/ml; PC: 408.9 ± 157.1 ng/ml, p = 0.03) was decreased in patients with poor control compared to patients with favorable control. Moreover, IL-8 was inversely correlated with IGF-1 (r = −0.40, p = 0.03) and positively correlated with HbA1C (r = 0.36, p = 0.03). Conclusions: In adolescents with T1DM and chronic, poor glucose control, increased serum IL-8 is associated with reduced IGF-1 suggesting a pro-inflammatory milieu that may contribute to alterations in the GH/IGF-1 axis. 相似文献
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Donald SA McLeod 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2010,31(1):9-19
This paper provides an overview on the biology, monitoring and management of differentiated thyroid cancer (DTC), with particular attention to issues of relevance to clinical chemistry. The incidence of DTC appears to be increasing and management strategies are evolving as we learn more about its natural history and response to therapy. Clinical chemistry techniques play a central role in these protocols. Technical limitations inherent in current monitoring tools can hamper follow-up, although progress is being made. The molecular basis of DTC is being delineated with the potential to develop new strategies for diagnosis, monitoring and management of this condition. 相似文献
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Cheaters must prosper: reconciling theoretical and empirical perspectives on cheating in mutualism 下载免费PDF全文
Emily I. Jones Michelle E. Afkhami Erol Akçay Judith L. Bronstein Redouan Bshary Megan E. Frederickson Katy D. Heath Jason D. Hoeksema Joshua H. Ness M. Sabrina Pankey Joel L. Sachs Klara Scharnagl Maren L. Friesen 《Ecology letters》2015,18(11):1270-1284
Cheating is a focal concept in the study of mutualism, with the majority of researchers considering cheating to be both prevalent and highly damaging. However, current definitions of cheating do not reliably capture the evolutionary threat that has been a central motivation for the study of cheating. We describe the development of the cheating concept and distill a relative‐fitness‐based definition of cheating that encapsulates the evolutionary threat posed by cheating, i.e. that cheaters will spread and erode the benefits of mutualism. We then describe experiments required to conclude that cheating is occurring and to quantify fitness conflict more generally. Next, we discuss how our definition and methods can generate comparability and integration of theory and experiments, which are currently divided by their respective prioritisations of fitness consequences and traits. To evaluate the current empirical evidence for cheating, we review the literature on several of the best‐studied mutualisms. We find that although there are numerous observations of low‐quality partners, there is currently very little support from fitness data that any of these meet our criteria to be considered cheaters. Finally, we highlight future directions for research on conflict in mutualisms, including novel research avenues opened by a relative‐fitness‐based definition of cheating. 相似文献