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991.
William C. Lemon Richard B. Levine 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,180(6):597-610
During the metamorphosis of Manduca sexta the larval nervous system is reorganized to allow the generation of behaviors that are specific to the pupal and adult stages.
In some instances, metamorphic changes in neurons that persist from the larval stage are segment-specific and lead to expression
of segment-specific behavior in later stages. At the larval-pupal transition, the larval abdominal bending behavior, which
is distributed throughout the abdomen, changes to the pupal gin trap behavior which is restricted to three abdominal segments.
This study suggests that the neural circuit that underlies larval bending undergoes segment specific modifications to produce
the segmentally restricted gin trap behavior. We show, however, that non-gin trap segments go through a developmental change
similar to that seen in gin trap segments. Pupal-specific motor patterns are produced by stimulation of sensory neurons in
abdominal segments that do not have gin traps and cannot produce the gin trap behavior. In particular, sensory stimulation
in non-gin trap pupal segments evokes a motor response that is faster than the larval response and that displays the triphasic
contralateral-ipsilateral-contralateral activity pattern that is typical of the pupal gin trap behavior. Despite the alteration
of reflex activity in all segments, developmental changes in sensory neuron morphology are restricted to those segments that
form gin traps. In non-gin trap segments, persistent sensory neurons do not expand their terminal arbors, as do sensory neurons
in gin trap segments, yet are capable of eliciting gin trap-like motor responses.
Accepted: 10 January 1997 相似文献
992.
993.
A programmed cell death pathway activated in carrot cells cultured at low cell density 总被引:13,自引:5,他引:8
Paul F. McCabe Alex Levine Per-Johan Meijer Nicolas A. Tapon Roger I. Pennell 《The Plant journal : for cell and molecular biology》1997,12(2):267-280
Programmed cell death (PCD) occurs in plants during development and defense, but the processes and mechanisms are not yet defined. Culture of carrot single cells at a cell density of <104 cells ml−1 activates a cell death process involving condensation and shrinkage of the cytoplasm and nucleus and fragmentation of the DNA. Modest abiotic stress treatments also cause cell condensation and shrinkage and the formation of DNA fragments, but the same abiotic stresses at high levels cause rapid necrosis with cell swelling and lysis. The common morphological features of cells dying at low cell density and following modest abiotic stress treatments suggest that these features reveal a PCD pathway in carrot. The addition of a cell-conditioned growth medium allows cells at low cell density to remain alive, demonstrating that cell-derived signal molecules suppress a pathway that is otherwise induced by default. Differences in the morphology of the dead cells suggest that proteolysis during PCD differs in detail in plants and animals; however, these findings show that plants, like animals, can control PCD by social signaling, and imply that the mechanism of PCD in plants and animals may be similar. Consistent with this, manipulation of signal pathway intermediates that regulate PCD in animals shows that Ca2+ and protein phosphorylation events are PCD pathway intermediates in carrot. 相似文献
994.
Louis Levine 《Animal behaviour》1985,33(4):1363-1364
995.
Evolutionary processes and cellular functions underlying divergence in Alexandrium minutum 下载免费PDF全文
996.
Sirui Zhou Amirthagowri Ambalavanan Daniel Rochefort Pingxing Xie Cynthia V. Bourassa Pascale Hince Alexandre Dionne-Laporte Dan Spiegelman Ziv Gan-Or Cathy Mirarchi Vessela Zaharieva Nicolas Dupré Hatasu Kobayashi Toshiaki Hitomi Kouji Harada Akio Koizumi Lan Xiong Patrick A. Dion Guy A. Rouleau 《American journal of human genetics》2016,99(5):1072-1085
997.
The Bacterial and Fungal Diversity of an Aged PAH- and Heavy Metal-Contaminated Soil is Affected by Plant Cover and Edaphic Parameters 总被引:1,自引:0,他引:1
998.
Hal Levine 《Ethnic and racial studies》2016,39(4):574-592
Stimulated by a recent government ban on kosher slaughter (shechita), and a whale stranding involving Ngāti Toa near Wellington, the author compares the quests of Indigenous and minority groups for cultural rights in Aotearoa (New Zealand). Observing Māori and Jews navigating in the contexts of the Treaty of Waitangi and human rights legislation, this paper provides concrete ethnographic examples that highlight how such claims articulate with the political and legal contexts in this Antipodean nation. 相似文献
999.
1000.
Nan Wu Levine Phillip Yuyan Han Kelly McDaniel Tami Annable Tianhao Zhou Heather Francis Shannon Glaser Qiaobing Huang Gianfranco Alpini Fanyin Meng 《Journal of cellular and molecular medicine》2016,20(2):195-203
Diabetes mellitus is one of the most severe endocrine metabolic disorders in the world that has serious medical consequences with substantial impacts on the quality of life. Type 2 diabetes is one of the main causes of diabetic liver diseases with the most common being non‐alcoholic fatty liver disease. Several factors that may explain the mechanisms related to pathological and functional changes of diabetic liver injury include: insulin resistance, oxidative stress and endoplasmic reticulum stress. The realization that these factors are important in hepatocyte damage and lack of donor livers has led to studies concentrating on the role of stem cells (SCs) in the prevention and treatment of liver injury. Possible avenues that the application of SCs may improve liver injury include but are not limited to: the ability to differentiate into pancreatic β‐cells (insulin producing cells), the contribution for hepatocyte regeneration, regulation of lipogenesis, glucogenesis and anti‐inflammatory actions. Once further studies are performed to explore the underlying protective mechanisms of SCs and the advantages and disadvantages of its application, there will be a greater understand of the mechanism and therapeutic potential. In this review, we summarize the findings regarding the role of SCs in diabetic liver diseases. 相似文献