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1.
S A Mercer H W Colvin R C Backus 《Comparative biochemistry and physiology. A, Comparative physiology》1988,90(3):481-489
1. Sheep rumens were insufflated with nitrogen to 5, 10, 15, and 20 cm water pressure and sustained at each pressure for 10 min. 2. Measurements included rumen motility, reticulorumen myoelectric activity, eructation frequency and volume, changes in tracheal pressure and rumen contraction amplitude. 3. As intra-rumen pressure increased, contractions designated as special secondary contractions appeared. 4. At a pressure of approximately 15 cm water, most of the special secondary contractions became regular secondaries; therefore, the special secondaries were called pro-secondary contractions. 5. Increased intra-rumen pressure was associated with respiratory distress. The recovery phase following, rumen insufflation was accompanied by hyperpnea. 相似文献
2.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
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Andrew P. Degnan Charles M. Conway Richard A. Dalterio Robert Macci Stephen E. Mercer Richard Schartman Cen Xu Gene M. Dubowchik John E. Macor 《Bioorganic & medicinal chemistry letters》2009,19(13):3555-3558
The calcitonin gene-related peptide (CGRP) receptor has been implicated in the pathogenesis of migraine. A class of urethanamide derivatives has been identified as potent inhibitors of the CGRP receptor. Compound 20 was found to be among the most potent (IC50 = 17 pM). It was shown to retain excellent aqueous solubility (>50 mg/mL, pH 7) while dramatically improving solution stability as compared to our previously disclosed development candidate, BMS-694153 (1). 相似文献
6.
The two molecular weight forms of rat phenylalanine hydroxylase are encoded by different messenger RNAs 总被引:1,自引:0,他引:1
Immunoprecipitation of the phenylalanine hydroxylase formed by translation of rat liver RNA in a rabbit reticulocyte cell-free protein synthesis system was used to examine the origin of the molecular weight heterogeneity of the enzyme. Sodium dodecyl sulfate-polyacrylamide electrophoresis of the immunoprecipitated products showed that in most cases a single specifically immunoprecipitated polypeptide was produced which corresponded to the higher molecular weight (H) form of phenylalanine hydroxylase (Mr = 50,000). The identity of the product was confirmed by immunological competition and peptide mapping. RNA from other rats, however, coded for both the H-form and the lower molecular weight (L) form of phenylalanine hydroxylase or for only the L-form. The evidence suggests that the L-form derives from a different mRNA, rather than by proteolysis of the H-form, an interpretation which is supported by the isolation of the lower form of phenylalanine hydroxylase from livers of some rats. 相似文献
7.
A total extract dot blot hybridization procedure for mRNA quantitation in small samples of tissues or cultured cells 总被引:3,自引:0,他引:3
A simple method for the estimation of specific mRNA concentrations in small tissue samples (as little as 1 mg) or cultured cells (lower limit 10(5) cells) is described. Guanidine hydrochloride extracts of whole cells or tissues are applied directly onto nitrocellulose and hybridized with the appropriate nick-translated probe. Loading according to DNA content allows expression of the result as concentration per cell. Hybridizing with a ribosomal RNA probe allows expression of results relative to rRNA and estimation of the RNA/DNA ratio in the sample. We describe the application of this procedure to the measurement of ceruloplasmin mRNA in tissues and cultured hepatocytes. 相似文献
8.
Four free radicals are trapped in methyl alpha-D-mannopyranoside X-irradiated and maintained at 77 K. All four have been identified, with high confidence levels, using ESR and ENDOR spectroscopy. One, an alkoxy radical located at O4, is characterized by a gmax of 2.059, an isotropic beta hydrogen hyperfine coupling (hfc) of 98 MHz, and small interactions due to gamma or delta hydrogens. The second, a secondary dioxyalkyl radical due to loss of hydrogen from C1 is characterized by one beta hfc with an isotropic component of 19.03 MHz. The third, a secondary hydroxyalkyl radical due to loss of hydrogen from C2 is characterized by two nonexchangeable hydrogens with isotropic beta interactions of 22.45 and 6.44 MHz and one exchangeable hydrogen with an isotropic beta interaction of 9.88 MHz. The fourth is a .CH2OR radical that is formed by the net loss of hydrogen from the methyl group. 相似文献
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J A Mercer N Bezodis D DeLion T Zachry M D Rubley 《Journal of electromyography and kinesiology》2006,16(2):198-204
Even though it is well known that electromyography (EMG) characteristics are influenced by electrode placement it is common to use a single pair of sensors per muscle for EMG. This study was designed to determine if the ability to distinguish between contraction conditions was influenced by sensor location. Subjects (n = 10; 27+/-5.3 years; 82+/-13.4 kg; 178+/-7.1 cm) completed six elbow flexor conditions: three isometric contraction intensities (100% maximum effort, 80%, 50%) and three isotonic contraction intensities (heavy weight, 80% and 50% of the weight). Three pairs of electrodes were placed centrally, medially and laterally on the biceps brachii belly in line with the muscle fibers. Isometric contractions were held for 5s, with the middle 3 s analyzed. Isotonic exercises included five repetitions of elbow flexion-extension, with the middle three repetitions analyzed. Average EMG (EMG(AVG)), root mean square EMG (EMG(RMS)) and mean power frequency (MPF) were calculated for each extracted data set. Dependent variables were analyzed using 2 (contraction type) x 3 (intensity) repeated measures ANOVAs per sensor. EMG(AVG) was influenced by the interaction between contraction type and intensity for all sensors (p < 0.05). EMG(RMS) as well as MPF were influenced by the interaction between contraction type and intensity for the lateral and central leads (p < 0.05) but not the medial leads (p > 0.05). Different conclusions could have been reached from the same experiment due to different sensor locations. These differences were primarily related to comparing contraction types (i.e., isotonic vs. isometric). 相似文献
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