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81.
The anatomical and morphological distribution of the G proteins G(o), G(i1) and 2, and Gs alpha-subunits in rat forebrain sections was determined using immunohistochemical techniques. Diffuse G(o) labeling occurred in the neuropil throughout the cortex, superficial layers of the entorhinal cortex, thalamus, several white matter fiber tracts, and hippocampus. G(i1) and 2 immunoreactivity was also located in the neuropil but produced a more fibrous pattern. Fibrous labeling of G(i1) and 2 was observed in the cortex, amygdala, hippocampal subfield CA3, and several white matter fiber tracts. Both G(o) and G(i1) and 2 labeling was present in the pencil fibers within the striatum and lateral geniculate nucleus. Gs labeling, in contrast to G(o) and G(i1) and 2, was generally cytoplasmic. Cytoplasmic Gs labeling was observed in the thalamus, habenula, dentate, geniculate nucleus, hypothalamus, and hippocampus. Intense Gs labeling was observed in the striatum parenchyma, choroid plexus, and infundibular stem. Based on our results, we conclude that the G proteins G(o), G(i1) and 2, and Gs are anatomically distributed differently throughout the brain. The diffuse neuropil labeling of G(o), fibrous neuropil labeling of G(i1) and 2, and cytoplasmic labeling of Gs strongly suggests that the G proteins are also differentially distributed morphologically within a neuron. The differential anatomical and cellular location of G proteins in the CNS may contribute to the coupling specificity between neurotransmitter receptors and G proteins.  相似文献   
82.
Weight of cotton immersed in an aqueous solution (various concentrations of NaOH) was explored as a basis for assessing penetration and sorption of the solute. The overall effects of swelling are indicated. Penetration and sorption phenomena can be identified with supplementary information, but they cannot yet be quantified. This methodology supplements and complements gel filtration as a means of measuring interactions between solutes in aqueous solution and cellulose fibers.  相似文献   
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The boreal forest contains almost half the total carbon pool of world forest ecosystems, and so has a very significant role in global biogeochemical cycles. The flux of greenhouse gases in and out of these forests is influenced strongly by disturbances such as diseases, logging and predominantly fire. It is important to quantify these disturbances to enable the modelling of major greenhouse gases. However, because of the remoteness and vastness of the boreal forest, little data is available on the type, extent, frequency and severity of these disturbances in Siberia. For burnt areas, two of the more responsive wavelengths are the short wave infra-red (SWIR) and the near infra-red (NIR). These produce a vegetation index, the normalised difference SWIR (NDSWIR) capable of detecting retrospective disturbances. Here we combine the NDSWIR from MODIS imagery acquired in the summer of 2003 with thermal anomaly data from 1992 to 2003 to detect and date areas which burnt at some point between 1992 and 2003. The semi-automated method is called SWIR and Thermal ANomalies for Detecting Disturbances (STANDD) and is complemented by an Normalised Difference Vegetation Index (NDVI) differencing method using MODIS 2002 and 2003 imagery to ensure reliable detection of area burnt in the year of image acquisition (i.e. 2003). The area of this study covers approximately 3 million km2 stretching from Lake Baikal in the south to the Laptev Sea in the north, above the Arctic Circle. Landsat ETM+ images were used to validate the shape and areal extent of the burnt areas resulting in an 81% overall accuracy with a kappa coefficient of agreement of 0.63.  相似文献   
86.
High-purity Si3N4 (with 2.5 wt% glassy SiO2) doped with 0 to 450 at.ppm of Ca was prepared as a model system to investigate the effects of grain-boundary segregants on fracture phenomenology at 1400°C. Subcritical crack-growth (SCG) resistance as well as creep resistance was degraded significantly by the presence of a small amount of Ca. The internal friction of the doped materials exhibited the superposition of a grain-boundary relaxation peak and a high-temperature background, and the apparent viscosity of the grain-boundary film was determined from the peak. Based on these experimental data, the fracture mechanism at 1400°C was divided into three regions: "brittle," SCG, and creep failure as a function of both external strain rate and Ca concentration, C Ca. From the investigation of the C Ca dependence of the critical strain rate for the transition from "brittle" to SCG fractures, the SCG phenomenon is suggested to be triggered by small-scale, grain-boundary sliding. The C Ca dependence of "steady-state" creep rate was far from the theoretical dependence of diffusional creep via a solution-precipitation mechanism. The discrepancy was interpreted to be due to the presence of an impurity-insensitive creep component. This component may correspond to the lowest limit of the tensile creep rate in Si3N4 polycrystalline materials containing intergranular glassy-SiO2 film.  相似文献   
87.
Throughout the developed world, community sports clubs are a high-risk setting for alcohol-impaired driving. The Good Sports program accredits community sports clubs to encourage implementation of alcohol-focussed harm-reduction and safe-transport strategies. This study tested for associations between participation in the Good Sports program and reduced rates of drink-driving amongst club members. Multilevel modelling indicated that for each season a club was in the program there was an 8% reduction in the odds of drink-driving. These findings may arise due to clubs with lower rates of alcohol use maintaining longer involvement in the program. However, the findings are also compatible with the intention of the Good Sports program to reduce the risk that club members will drive whilst alcohol impaired.  相似文献   
88.
Direct injection electrospray ionization mass spectrometry (ESI-MS) without prior analyte separation was investigated for the analysis of whole cell suspensions of bacteria. Thirty-six strains of aerobic endospore-forming bacteria, consisting of six Bacillus species and one Brevibacillus species, were studied  相似文献   
89.
Using survey data from 2,000 low-income adult respondents in each of five states, this DataWatch assesses how uninsured, low-income adults differ from low-income adults who have public or private insurance and how Medicaid expansions have affected insurance coverage patterns across states with different eligibility policies. Findings show that the proportion of low-income uninsured adults is two to three times higher in states that have not expanded Medicaid eligibility beyond relatively low welfare levels. Compared with persons who have either Medicaid or private insurance, uninsured persons report more difficulties getting needed care, are less likely to have a regular provider, and rate the care they do receive as lower quality.  相似文献   
90.
Until now, taste was the only primary sensory modality for which the human central nervous system pathways were unknown. We report sensations evoked by stimulation at microampere current levels in the region of the human thalamic nucleus (ventralis caudalis parvocellularis internis) corresponding to the monkey taste relay nucleus. Stimulation in this region during awake neurosurgical procedures evoked special visceral/somatic (taste/pungent smell), general visceral (fullness of a hollow viscus), as well as painful and nonpainful general somatic sensations. General somatic or visceral sensation was evoked by stimulation at 80% of sites where special visceral/somatic sensation was evoked. These results suggest that primate taste relay mediates multiple sensations in addition to taste.  相似文献   
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