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111.
The ability of bombesin (BN)-like peptides to stimulate phosphatidylinositol turnover in rat brain slices was investigated. BN (1 μM) significantly stimulated inositol-1-phosphate (IP1) but not inositol-4,5-biphosphate (IP2) or inositol-1,4,5-trisphosphate (IP3) production using frontal cortex slices in the presence of LiCl (7.5 mM); BN had no effect on cAMP or cGMP levels. BN and the structurally-related gastrin releasing peptide (GRP) elevated IP1 levels in a dose-dependent manner. Similarly, nanomolar concentrations of the GRP fragment (Ac-GRP20–27) significantly elevated IP1 levels, whereas micromolar concentrations of the inactive GRP1–16 did not. BN significantly elevated IP1 levels in those brain regions enriched in BN receptors such as the olfactory bulb, hippocampus, striatum, thalamus and frontal cortex, whereas IP1 levels were not significantly increased in areas which have a low density of BN receptors such as the cerebellum, medulla/pons and midbrain. These data suggest that CNS BN receptors may utilize phosphatidylinositol as a second messenger. 相似文献
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Dr. agr. Chandra Bhushan Prasad Mishra Prof. Dr. agr. habil. Lothar Behr 《Archives Of Phytopathology And Plant Protection》2013,46(6):373-376
Abstract In Anbetracht der weitreichenden Bedeutung des VIII. Internationalen Pflanzenschutzkongresses, der in der Zeit vom 22. bis 26. August 1975 in Moskau stattfand, hält es die Redaktion für erforderlich, die anläßlich des Kongresses verabschiedete Resolution im Wortlaut wiederzugeben. 相似文献
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Michael A. Huffman Raveendra Kumara Yoshi Kawamoto Prasad M. Jayaweera Massimo Bardi Charmalie A. D. Nahallage 《American journal of primatology》2020,82(3):e23113
Allen's rule (1877) predicts ecogeographical anatomical variation in appendage proportions as a function of body temperature regulation. This phenomenon has been tested in a variety of animal species. In macaques, relative tail length (RTL) is one of the most frequently measured appendages to test Allen's rule. These studies have relied on museum specimens or the invasive and time-consuming capturing of free-ranging individuals. To augment sample size and lessen these logistical limitations, we designed and validated a novel noninvasive technique using digitalized photographs processed using LibreCAD, an open-source 2D-computer-aided design (CAD) application. This was used to generate pixelated measurements to calculate an RTL equivalent, the Tail to Trunk Index (TTI) = (tail [tail base to anterior tip] pixel count/trunk [neck to tail base] pixel count). The TTI of 259 adult free-ranging toque macaques (Macaca sinica) from 36 locations between 7 and 2,087 m above sea level (m.a.s.l.) was used in the analysis. Samples were collected from all three putative subspecies (M. s. sinica, aurifrons, and opisthomelas), at locations representing all altitudinal climatic zones where they are naturally distributed. These data were used to test whether toque macaque tail length variation across elevation follows Allen's rule, predicting that RTL decreases with increasing elevation and lower temperature. Our results strongly supported this prediction. There was also a statistically significant, negative correlation between elevation and annual average temperature. The best predictor for the TTI index was elevation. Significant subspecies differences in RTL are linked in part to their ecological and altitudinal niche separation, but overall the variation is seen as the species' adaptation to climate. The method developed for the quick morphometric assessment of relative body proportions, applicable for use on unhabituated free-ranging animals, widens the range of materials available for research studying morphological characteristics and their evolution in primates. 相似文献
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Narasimsetti Srinivasa Rao Megala Rajesh Kumcham Prasad Gutturu Rajasekhara Reddy B. Deva Prasad Raju S. Dhanapandian 《Luminescence》2020,35(5):721-727
Sm3+ ions doped strontium lithium lead borate glasses (SLLB:Sm) were prepared using a conventional melt‐quenching technique. The glasses were analyzed using X‐ray diffractometry and Fourier transform infrared spectroscopy, optical absorption, fluorescence spectral analysis, and fluorescence lifetime decay. The Judd–Ofelt (J–O) parameters and radiative parameters of the SLLB:Sm10 glass (1.0 mol% Sm3+ ion‐doped glass) were calculated using J–O theory. From the emission spectra, among all the synthesized glass, SLLB:Sm10 glass had the highest emission intensity for 4G5/2→6H11/2 transition (610 nm). Emission parameters, such as stimulated emission cross‐section and optical gain bandwidth, were calculated. For all concentrations of Sm3+ ions, the decay profile showed an exponential nature and decreased when the Sm3+ ion concentration was increased due to a concentration quenching effect. This result suggests that the synthesized SLLB:Sm10 glass could be used for application in high‐density optical memory devices. 相似文献
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