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991.
The Neurokinin 1 Receptor (NK1R), which binds Substance P, is expressed in discrete populations of neurons throughout the nervous system, where it has numerous roles including the modulation of pain and affective behaviors. Here, we report the generation of a NK1R‐CreER knockin allele, in which CreERT2 replaces the coding sequence of the TACR1 gene (encoding NK1R) in order to gain genetic access to these cells. We find that the NK1R‐CreER allele mediates recombination in many regions of the nervous system that are important in pain and anxiety including the amygdala, hypothalamus, frontal cortex, raphe nucleus, and dorsal horn of the spinal cord. Other cell types that are labeled by this allele include amacrine cells in the retina and fibroblasts in the skin. Thus, the NK1R‐CreER mouse line is a valuable new tool for conditional gene manipulation enabling the visualization and manipulation of cells that express NK1R.  相似文献   
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993.

Background  

Molecular sequence data have become the standard in modern day phylogenetics. In particular, several long-standing questions of mammalian evolutionary history have been recently resolved thanks to the use of molecular characters. Yet, most studies have focused on only a handful of standard markers. The availability of an ever increasing number of whole genome sequences is a golden mine for modern systematics. Genomic data now provide the opportunity to select new markers that are potentially relevant for further resolving branches of the mammalian phylogenetic tree at various taxonomic levels.  相似文献   
994.
The adaptive significance of the multiple evolution of bipedalism is surveyed and discussed. Probable modes of origin and the relative advantages of saltatorial and alternating gaits are expressed in terms of foot stability, speed of progression, directional changes, control of momentum and overcoming body inertia. It is suggested that analysis of primate locomotion by high-speed cinematography is a necessary basic step toward correlation of structure with behavior.  相似文献   
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The pathologic findings in 13 cases of staphylococcal disease in New Zealand white rabbits were described. Subcutaneous abscesses and embolic pyemic abscesses in kidney, heart, brain, and lung were found. Conjunctivitis, rhinitis, otitis media, and fibrinous pneumonia also occurred. One rabbit had a valvular endocarditis. Staphylococcus aureus, coagulase-positive, and fermenting mannitol were isolated from the lesions described. Staphylococcal disease was diagnosed in 13 of the 171 (7.6%) rabbits necropsied during a 3-yr period. Disseminated staphylococcal lesions were observed only in rabbits during this time.  相似文献   
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Insect herbivory can strongly influence ecosystem nutrient dynamics, yet the indirect effects of herbivore‐altered litter quality on subsequent decomposition remain poorly understood. The northern tamarisk beetle Diorhabda carinulata was released across several western states as a biological control agent to reduce the extent of the invasive tree Tamarix spp. in highly‐valued riparian ecosystems; however, very little is currently known about the effects of this biocontrol effort on ecosystem nutrient cycling. In this study, we examined alterations to nutrient dynamics resulting from beetle herbivory in a Tamarix‐invaded riparian ecosystem in the Great Basin Desert in northern Nevada, USA, by measuring changes in litter quality and decomposition, as well as changes in litter quantity. Generally, herbivory resulted in improved leaf litter chemical quality, including significantly increased nitrogen (N) and phosphorus (P) concentrations and decreased carbon (C) to nitrogen (C:N), C:P, N:P, and lignin:N ratios. Beetle‐affected litter decomposed 23% faster than control litter, and released 16% more N and 60% more P during six months of decomposition, as compared to control litter. Both litter types showed a net release of N and P during decomposition. In addition, herbivory resulted in significant increases in annual rates of total aboveground litter and leaf litter production of 82% and 71%, respectively, under the Tamarix canopy. Our finding that increased rates of N and P release linked with an increased rate of mass loss during decomposition resulting from herbivore‐induced increases in litter quality provides new support to the nutrient acceleration hypothesis. Moreover, results of this study demonstrate that the introduction of the northern tamarisk beetle as biological control to a Tamarix‐invaded riparian ecosystem has lead to short‐term stimulation of nutrient cycling. Alterations to nutrient dynamics could have implications for future plant community composition, and thus the potential for restoration of Tamarix‐invaded ecosystems.  相似文献   
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