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Intracranial injections of Angiotensin II (AII) through permanent brain chemodes aimed for the lateral hypothalamic, lateral preoptic, or septal region evoked drinking of tap water from Mongolian gerbils in normal water balance. When lettuce was the only available free water source, AII injections elicited prolonged lettuce-eating responses. l-Norepinephrine injections did not elicit eating of food pellets but, like AII, proved to be a reliable and potent dipsogenic agent. Carbachol, a cholinergic agonist, failed to elicit any ingestive behaviors over a wide dose range. The species-typical foot-thumping behavior of the gerbil was seen during some tests with all drugs utilized. It is suggested that the dipsogenic property of AII across a wide variety of species reflects the nature of a primitive, i.e., phylogenetically old, brain mechanism shared by most mammals to deal with problems of water economy, while the organization and utilization of other central neurochemicals in thirst-related substrates may vary among species.  相似文献   
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This study assesses whether stroke mortality trends have been less favorable among lower than among higher socioeconomic groups. Longitudinal data on mortality by socioeconomic status were obtained for Finland, Norway, Denmark, Sweden, England/Wales, and Turin, Italy. Data covered the entire population or a representative sample. Stroke mortality rates were calculated for the period 1981-1995. Changes in stroke mortality rate ratios were analyzed using Poisson regression and compared with rate ratios in ischemic heat disease mortality. Trends in stroke mortality were generally as favorable among lower as among higher socioeconomic groups, such that socioeconomic disparities in stroke mortality persisted and remained of a similar magnitude in the 1990s as in the 1980s. In Norway, however, occupational disparities in stroke mortality significantly widened, and a nonsignificant increase was observed in some countries. In contrast, disparities in ischemic heart disease mortality widened throughout this period in most populations. Improvements in hypertension prevalence and treatment may have contributed to similar stroke mortality declines in all socioeconomic groups in most countries. Socioeconomic disparities in stroke mortality generally persisted and may have widened in some populations, which fact underlines the need to improve preventive and secondary care for stroke among the lower socioeconomic groups.  相似文献   
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Electronic medical records of a large veterinary practice were used for surveillance of potential space-time clustering of adverse events associated with rabies vaccination in dogs. The study population was 257,564 dogs vaccinated in 169 hospitals in 13 US metropolitan areas during a 24-month period. Using a scan statistic for population rate data, significant space-time clusters were identified involving the Atlanta and Tampa/St. Petersburg areas during a 4-month period. Separate spatial-temporal analyses of these cities using coordinates for individual address coordinates identified one significant patient cluster (P=0.002), associated with a 23.26 km-radius area in Atlanta (20 adverse events in 702 dogs; 2.85%) from November 2002 through February 2003. This percentage of adverse events was significantly increased after adjustment for host-related factors and the number of concurrent vaccinations.  相似文献   
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