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61.
E. Guerrero-Lindner M. Castro J. M. MuÑoz M. P. Arruebo M.D. Murillo L. Buéno† & M.A. plaza 《Neurogastroenterology and motility》2003,15(3):307-316
Cytokines are involved in fever and other symptoms of the acute phase response induced by endotoxins. The aim of this work was to study the involvement of central tumour necrosis factor-alpha (TNF-alpha) in the changes induced by lipopolysaccharide (LPS) on gastrointestinal (GI) motility in sheep. Body temperature and myoelectric activity of the antrum, duodenum and jejunum was recorded continuously. Intravenous (i.v.) administration of LPS (0.1 micro g kg-1)-induced hyperthermia, decreased gastrointestinal myoelectric activity and increased the frequency of the migrating motor complex (MMC). These effects started 40-50 min after LPS and lasted for 6-7 h. TNF-alpha (50 and 100 ng kg-1) mimicked these effects when injected intracerebroventricularly (i.c.v.) but not i.v. Pretreatment with soluble recombinant TNF receptor (TNFR:Fc, 10 micro g kg-1, i.c.v.) abolished the TNF-induced actions and reduced those evoked by LPS. Furthermore, the effects induced by either LPS or TNF were suppressed by prior i.c.v. injection of indomethacin (100 micro g kg-1). In contrast, the i.v. injections of TNFR:Fc or indomethacin were ineffective. Our data suggest that LPS disturbs GI motility in sheep through a central pathway that involves TNF-alpha and prostaglandins sequentially. 相似文献
62.
63.
Summary Throughout history, different etiologies have been suggested for torus palatinus. In more recent years, however, torus palatinus has been attributed to heredity; a case which confirms this is presented. The relevant literature is reviewed. 相似文献
64.
Carl Andrew Castro John B. Hogan Kimberly A. Benson Christina W. Shehata Michael R. Landauer 《Pharmacology, biochemistry, and behavior》1995,50(4):521-526
Experimental drugs and compounds that do not easily dissolve in water or saline are frequently combined with vehicles like solvents, detergents, or vegetable oils. Yet very little has been reported on the behavioral effects of vehicles. In this study, we assessed the effects of a vegetable oil (emulphor-620), two detergents (Tween-20 and Tween-80), and two solvents [dimethyl sulphoxide (DMSO) and ethanol] on the locomotor activity in CD2F1 male mice. Locomotor activity was monitored for 12 h after vehicle administration (IP). The concentrations for each vehicle were expressed as percent of vehicle in saline (v/v). Emulphor-620 did not affect locomotor activity at any concentration tested (2%, 4%, 8%, 16%, and 32%). Tween-20 significantly decreased locomotor activity at a concentration of 16% and Tween-80 at 32%. DMSO significantly decreased locomotor activity at concentrations of 32% and 64%. In contrast, ethanol produced a biphasic behavioral response: increased activity at a concentration of 16% and decreased activity at a concentration of 32%. These results will facilitate the selection and concentration of vehicles to be used in combination with experimental drugs or test agents. 相似文献
65.
Flavia Nogueira Edinaldo Castro E. Silva Wolfgang Junk 《International journal of environmental health research》1997,7(3):181-192
The Pocone gold minings are situated in the Bento Gomes River Basin, at the border of the Pantanal of Mato Grosso. Gold-bearing quartz veins are removed from the subsoils, milled with water, centrifuged and the heavier fraction is subsequently mixed with mercury for gold separation. The gold mining activities caused a very intensive landscape change, threatening many environmental processes like sediment control and storage and recycling capacity of mercury. Cold Vapor Atomic Fluorescence System (CVAFS) was used to determinate total mercury in water, suspended material and sediments from Bento Gomes River, sampled monthly for 1 year. Apart from the fact that mercury concentrations are low in water and bottom sediments, they are slightly higher in relation to background levels measured in the area. The concentration in suspended material is also lower than other rivers with gold mining activities, but the floodplains of the Bento Gomes River act as mercury sinks. Therefore, the discharge of mercury into the Pantanal floodplain should be avoided, in spite of actual contamination of the system being very low. 相似文献
66.
67.
E. A. Rosenbaum A. Caballero de Castro L. Gauna A. M. Pechen de D'Angelo 《Archives of environmental contamination and toxicology》1988,17(6):831-835
The exposure of newly fertilized amphibian embryos to malathion (44 mg/L) produces 67% mortality on the fifth day of exposure. Clinical signs of intoxication are evident on the fourth day. A variety of biochemical parameters, such as enzyme activity, lipid and protein content, was examined in control and malathion-treated embryos. The activity of acetyl, butyrylcholinesterase and aliesterase are quickly inhibited. An interference with cellular protein synthesis and redistribution is possible. A slight increase in total phospholipids is evident after 24 hr of exposure. 相似文献
68.
P. A. Gómez R. D. Lobato J. J. Rivas A. Cabrera R. Sarabia S. Castro M. Castañeda J. M. Cañizal 《Acta neurochirurgica》1989,101(1-2):35-41
Summary The authors review the literature on subarachnoid haemorrhage of unknown aetiology (SAHUE) and analyze a personal series of 212 patients diagnosed as SAHUE. These patients represent 30% of all cases of primary SAH admitted over a 14.5 year period.The age, sex, antecedents and initial clinical presentation of patients with SAHUE were indistinguishable from those of patients with subarachnoid haemorrhage due to ruptured aneurysm (SAHRA). However, the present series of SAHUE compare favourably with both a personal and a previously reported series of SAHRA insofar as clinical grade on admission (94% of patients in grades I–II of Botterell), presence of blood on CT (51%), vasospasm (5%), ischaemic deficits (3.3%), persistent hydrocephalus (3.5%), rebleeding (6%) and fatal result (3.9%) are concerned.The amount of blood on CT scan in our patients with SAHUE was associated with a significantly higher incidence of brain ischaemia and hydrocephalus but did not correlate with the Botterell grade on admission or final outcome, which were good in the majority of cases regardless of the presence or not of visible cisternal haemorrhage. The results of the present series confirm that the final prognosis of patients with primary SAH showing normal four-vessel cerebral angiography is essentially favourable. 相似文献
69.
M R González Delgado D R López Castro A M Longa Monteagudo 《Revista cubana de enfermería》1989,5(1-2):77-84
Evolution of the newborn infant weighing 1,000-1,499 g, was studied in 1986 in the "Mariana Grajales" Gynecologic and Obstetric Teaching Provincial Hospital, Department of Neonatology, Santa Clara. Data was obtained from the clinical histories of the newborns and of their mothers. A control group was selected in order to analyze and compare the causes of low birthweight, and as causes of it were determined age and height, and as associated diseases, urinary sepsis, anemia and toxemia of pregnancy. Premature rupture of membranes was significant. Half of the infants of the group under study was severe and moderately depressed. At the somatic evolution was observed a trend to increment and a high coefficient of correlation within the three variables under study. Main nursing actions offered fit up to the attention of these neonates. 相似文献
70.
Measurement of radiation isocenter is a fundamental part of commissioning and quality assurance (QA) for a linear accelerator (linac). In this work we present an automated procedure for the analysis of the stars-shots employed in the radiation isocenter determination. Once the star-shot film has been developed and digitized, the resulting image is analyzed by scanning concentric circles centered around the intersection of the lasers that had been previously marked on the film. The center and the radius of the minimum circle intersecting the central rays are determined with an accuracy and precision better than 1% of the pixel size. The procedure is applied to the position and size determination of the radiation isocenter by means of the analysis of star-shots, placed in different planes with respect to the gantry, couch and collimator rotation axes. 相似文献