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1.
Between the mean daily density of 28 kHz atmospherics and the onset of epileptic fits there is a highly significant correlation coefficient (r) of 0.30; there is a negative coefficient of –0.20 between the fits and the mean daily density of 10 kHz atmospherics. The onset of heart infarction is correlated with 28 kHz atmospherics (r=0.15). Furthermore, we have discovered that sudden deafness is also correlated with certain configurations of atmospherics. In this paper we report the following correlation coefficients between the inflammatory reaction of rats to a carrageenan injection (rci) into a hind paw and the mean daily pulse rate of atmospherics of the same day:r=0.49 for the 8 kHz atmospherics (P<0.02) andr=0.44 for the 10 kHz atmospherics (P<0.04). The correlations between rci reaction and other atmospherics (12 and 28 kHz) are smaller and not significant. By the method of multiple linear regression we found a multipleR=0.54 between rci reaction and the 8 and 10 kHz atmospherics (the regression function for the rci reaction is 0.15+0.004×8 kHz+0.002×10 kHz,P<0.05).  相似文献   
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Dance is ubiquitous among humans and has received attention from several disciplines. Ethnographic documentation suggests that dance has a signaling function in social interaction. It can influence mate preferences and facilitate social bonds. Research has provided insights into the proximate mechanisms of dance, individually or when dancing with partners or in groups. Here, we review dance research from an evolutionary perspective. We propose that human dance evolved from ordinary (non-communicative) movements to communicate socially relevant information accurately. The need for accurate social signaling may have accompanied increases in group size and population density. Because of its complexity in production and display, dance may have evolved as a vehicle for expressing social and cultural information. Mating-related qualities and motives may have been the predominant information derived from individual dance movements, whereas group dance offers the opportunity for the exchange of socially relevant content, for coordinating actions among group members, for signaling coalitional strength, and for stabilizing group structures. We conclude that, despite the cultural diversity in dance movements and contexts, the primary communicative functions of dance may be the same across societies.  相似文献   
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Recruitment of the growth factor receptor-bound protein 2 (Grb2) by the plasma membrane-associated adapter protein downstream of kinase 3 (Dok-3) attenuates signals transduced by the B cell antigen receptor (BCR). Here we describe molecular details of Dok-3/Grb2 signal integration and function, showing that the Lyn-dependent activation of the BCR transducer kinase Syk is attenuated by Dok-3/Grb2 in a site-specific manner. This process is associated with the SH3 domain-dependent translocation of Dok-3/Grb2 complexes into BCR microsignalosomes and augmented phosphorylation of the inhibitory Lyn target SH2 domain-containing inositol 5′ phosphatase. Hence, our findings imply that Dok-3/Grb2 modulates the balance between activatory and inhibitory Lyn functions with the aim to adjust BCR signaling efficiency.  相似文献   
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Prostanoids, especially prostaglandin (PG) E(2), are important mediators of uterine relaxation and contractions during gestation and parturition. Inhibitors of PG formation as well as PG analogues are used to modulate uterine tonus. So far, only limited data are available regarding the expression of prostanoid receptors in human pregnant myometrium. In the present study, the expression of the receptors for PGE(2) (EP1, EP2, EP3, EP4), PGF(2alpha) (FP), prostacyclin (IP), and thromboxane A(2) (TP) in human pregnant myometrium was studied by RT-PCR, in situ hybridization and immunohistochemistry. Myometrial tissue was obtained from five women at term and not in labour and from two women who delivered preterm. Tissue specimens were excised from the upper edge of the transverse lower uterine segment incision. In all tissues analysed, EP1, EP2, EP3, EP4, FP, TP and IP receptor mRNA and protein was detected. mRNA expression for PGD(2) (DP) receptor was not detected in the majority of tissue specimens. EP1, EP2, EP4, IP, TP and FP receptor protein was detected on myometrial smooth muscle cells, whereas EP3 receptor protein was only expressed by stromal and endothelial cells. In situ hybridization experiments yielded similar results. The expression of the EP2 receptor mRNA was inversely related to gestational age. We suggest that the contractile effect of PGE(2) at term is probably mediated directly by the EP1 receptor expressed in myometrial smooth muscle cells and indirectly by the EP3 receptor expressed in stromal cells and a decrease in EP2 receptor expression.  相似文献   
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Integrated data of calcareous plankton and benthic foraminifers from the pre-evaporitic interval of Trave section (Central Italy) allowed the reconstruction of surface and bottom-water conditions in the Central Mediterranean during the interval from 7.61 to 6.33 Ma, preceding the Messinian Salinity Crisis.Our data point out a three-step paleoenvironmental evolution. During the first stage (7.61-7.02 Ma) benthic foraminiferal assemblages depict stable, well-oxygenated and ventilated bottom-water conditions, while the surface water records variable temperature and high nutrient conditions, probably associated with strong seasonality. The second stage (7.02-6.70 Ma) points to unfavourable bottom-water condition, triggered by deep-sea stagnation. This is witnessed by a significant decrease in oxygen concentration and biotic diversity, and by the presence of stress-tolerant taxa. A general warming of the surface water and a strongly stratified water column, characterized by an expanded mixed layer, are also recorded.From 6.70 Ma onwards (third stage), a prominent change to more restricted, low-oxygenated, hypersaline conditions at the sea floor is testified by the total disappearance of deep-dwelling planktonic foraminifers and the increasing abundance of stress-tolerant species. Calcareous plankton reflects high instability of the surface water in terms of nutrients, temperature and salinity. During this stage the environmental deterioration reaches intermediate depths in the water column.The initial change toward a step-wise isolation of the Central Mediterranean bottom-waters is probably related to a general warming, responsible for a first slowing-down of the vertical circulation, favouring stratification of surface and intermediate waters and stagnation of bottom-waters. This warming is related to the restricted connection between the Mediterranean Sea and the Atlantic Ocean, which occurred since 7.146 Ma.In the Trave section, the isolation of bottom-waters most likely occurred at the same time as in other Mediterranean sections. However, due to the presence of a hiatus it cannot be excluded that it occurred with a delay of ~ 100 kyr, probably related to the shallower paleodepth of the basin.  相似文献   
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Dipyrone is a common antipyretic drug and the most popular non-opioid analgesic in many countries. In spite of its long and widespread use, molecular details of its fate in the body are not fully known. We administered dipyrone orally to mice. Two unknown metabolites were found, viz. the arachidonoyl amides of the known major dipyrone metabolites, 4-methylaminoantipyrine (2) and 4-aminoantipyrine (3). They were identified by ESI-LC-MS/MS after extraction from the CNS, and comparison with reference substances prepared synthetically. The arachidonoyl amides were positively tested for cannabis receptor binding (CB(1) and CB(2)) and cyclooxygenase inhibition (COX-1 and COX-2 in tissues and as isolated enzymes), suggesting that the endogenous cannabinoid system may play a role in the effects of dipyrone against pain.  相似文献   
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Phosphoenolpyruvate carboxylase (PEPC) was purified from leaves of four species of Alternanthera differing in their photosynthetic carbon metabolism: Alternanthera sessilis (C3), A. pungens (C4), A. ficoides and A. tenella (C3-C4 intermediates or C3-C4). The activity and properties of PEPC were examined at limiting (0.05 mM) or saturating (10 mM) bicarbonate concentrations. The Vmax as well as Km values (for Mg2+ or PEP) of PEPC from A. ficoides and A. tenella (C3-C4 intermediates) were in between those of C3 (A. sessilis) and C4 species (A. pungens). Similarly, the sensitivity of PEPC to malate (an inhibitor) or G-6-P (an activator) of A. ficoides and A. tenella (C3-C4) was also of intermediate status between those of C3 and C4 species of A. sessilis and A. pungens, respectively. In all the four species, the maximal activity (Vmax), affinity for PEP (Km), and the sensitivity to malate (KI) or G-6-P (KA) of PEPC were higher at 10 mM bicarbonate than at 0.05 mM bicarbonate. Again, the sensitivity to bicarbonate of PEPC from C3-C4 intermediates was in between those of C3- and C4-species. Thus the characteristics of PEPC of C3-C4 intermediate species of Alternanthera are intermediate between C3- and C4-type, in both their kinetic and regulatory properties. Bicarbonate could be an important modulator of PEPC, particularly in C4 plants. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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