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1.
The purpose of the present study was (i) to compare secretory responses of prolactin and corticosterone to the acute stress of immobilization in male rats of the Lewis and Long Evans strains and (ii) to compare secretion of the two hormones in rats with fully developed adjuvant arthritis (AA) and their relationship with the intensity of the inflammatory reaction. A short immobilization of 5 min induced equal elevations of both hormones in both strains, but 20-min immobilization produced significantly stronger responses in Long Evans rats than in Lewis rats. AA inhibited prolactin secretion equally in both strains (from 11.6 +/- 1.3 ng/ml to 4.2 +/- 0.6 ng/ml in Lewis rats, p < 0.01, and from 3.7 +/- 0.6 to 2.12 +/- 0.1 ng/ml in Long Evans rats, p < 0.05), but caused a conspiciously larger elevation of corticosterone in the Long Evans than in the Lewis animals (11.5 +/- 1.2 microg/dl in Long Evans rats versus 5.1 +/- 0.5 microg/dl in Lewis rats, p < 0.01) while basal levels were similar. The larger corticosterone response in the Long Evans rats was associated with a stronger inflammatory reaction assessed by hind paw swelling (2.3 +/- 0.1 ml for Long Evans rats versus 1.8 +/- 0.08 ml for Lewis rats, p < 0.01) and plasma levels of nitric oxide (47.5 +/- 5.7 microM for Long Evans rats versus 28.7 +/- 2.5 microM for Lewis rats, p < 0.01) than in the Lewis males with lower corticosterone levels. In conclusion, there are significant, obviously genetically based, differences in the corticosterone responses to both immobilization and AA between the two strains, with the Long Evans rats reacting more strongly than the Lewis rats. The lack of the expected inverse relationship between corticosterone levels and the intensity of the inflammation indicates that the activity of corticosterone is not its primary determinant and that other important factors are involved.  相似文献   
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BackgroundReductions in total hippocampus volume have frequently been reported in MRI studies in major depressive disorder (MDD), but reports of differences in total amygdala volume have been inconsistent. Childhood maltreatment is an important risk factor for MDD in adulthood and may affect the volume of the hippocampus and amygdala. In the present study, we examined associations between the volumes of the amygdala subnuclei and hippocampal subfields and history of childhood maltreatment in participants with MDD.MethodsWe recruited 35 patients who met the DSM-IV criteria for MDD and 35 healthy controls. We acquired MRI data sets on a 4.7 T Varian Inova scanner. We manually delineated the amygdala subnuclei (lateral, basal and accessory basal nuclei, and the cortical and centromedial groups) and hippocampal subfields (cornu ammonis, subiculum and dentate gyrus) using reliable volumetric methods. We assessed childhood maltreatment using the Childhood Trauma Questionnaire in participants with MDD.ResultsIn participants with MDD, a history of childhood maltreatment had significant negative associations with volume in the right amygdala, anterior hippocampus and total cornu ammonis subfield bilaterally. For volumes of the amygdala subnuclei, such effects were limited to the basal, accessory basal and cortical subnuclei in the right hemisphere, but they did not survive correction for multiple comparisons. We did not find significant effects of MDD or antidepressant treatment on volumes of the amygdala subnuclei.LimitationsOur study was a cross-sectional study.ConclusionOur results provide evidence of negative associations between history of childhood maltreatment and volumes of medial temporal lobe structures in participants with MDD. This may help to identify potential mechanisms by which maltreatment leads to clinical impacts.  相似文献   
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Brain Imaging and Behavior - Cognitive impairment is now recognized in a subset of patients with amyotrophic lateral sclerosis (ALS). The objective of the study was to identify group differences...  相似文献   
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Surgery remains the only curative treatment for pancreaticobiliary tumors. These patients typically present in a malnourished state. Various screening tools have been employed to help with preoperative risk stratification. Examples include the subjective global assessment (SGA), malnutrition universal screening tool (MUST), and nutritional risk index (NRI). Adequate studies have not been performed to determine if perioperative interventions, based on nutrition risk assessment, result in less morbidity and mortality. The routine use of gastric decompression with nasogastric sump tubes may be unnecessary following elective pancreatic resections. Instead, placement should be selective and employed on a case-by-case basis. A wide variety of feeding modalities are available, oral nutrition being the most effective. Artificial nutrition may be provided by temporary nasal tube (nasogastric, nasojejunal, or combined nasogastrojejunal tube) or surgically placed tube [gastrostomy (GT), jejunostomy (JT), gastrojejunostomy tubes (GJT)], and intravenously (parenteral nutrition, PN). The optimal tube for enteral feeding cannot be determined based on current data. Each is associated with a specific set of complications. Dual lumen tubes may be useful in the presence of delayed gastric emptying (DGE) as the stomach may be decompressed while feeds are delivered to the jejunum. However, all feeding tubes placed in the small intestine, except direct jejunostomies, commonly dislodge and retroflex into the stomach. Jejunostomies are associated with less frequent, but more serious complications. These include intestinal torsion and bowel necrosis. PN is associated with septic, metabolic, and access-related complications and should be the feeding strategy of last-resort. Enteral feeds are clearly preferred over parental nutrition. A sound understanding of perioperative nutrition may improve patient outcomes. Patients undergoing pancreatic cancer surgery should undergo multidisciplinary nutrition screening and intervention, and the surgical/oncological team should include nutrition professionals in managing these patients in the perioperative period.  相似文献   
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Endothelin-1 (ET-1) is known to have a direct arrhythmogenic effect in the mammalian heart. Diabetes mellitus is accompanied by a series of endothelial and cardiac disfunctions; however, little is known about ET-1-induced direct arrhythmias in diabetes mellitus. Therefore, we infused ET-1 (33 pmol/min) into the left anterior descending coronary artery of 28 mongrel dogs, and measured basic hemodynamic parameters, coronary flow and an electrocardiogram. Diabetes mellitus was induced by alloxan (Group 4) and experiments were carried out 8 weeks later. Metabolically healthy dogs served as controls (Group 2). In a further control group, local hyperglycemia was induced by intracoronary glucose infusion (Group 3). ET-1 infusion induced prolongation of the QT-time and frequency-adjusted QT-time in all groups. Other electrophysiological parameters were comparable between the groups. This was followed by the occurence of ventricular premature beats, coupled extra-beats and later sustained ventricular tachycardia. Most of the experiments were terminated by ventricular fibrillation. The onset of arrhythmias was shorter in diabetic dogs as compared with control and locally hyperglycemic animals (18 +/- 8 minutes versus 24 +/- 8 minutes and 30 +/- 28 minutes, P < 0.05). However, there was no difference in the number of ventricular fibrillations, and the total elapsed time until the termination of the experiments. Therefore, the diabetic heart seems to be more prone to ET-1-induced arrhythmias and this is probably not a result of locally high glucose concentrations.  相似文献   
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Etiprednol dicloacetate (ethyl 17alpha-dichloroacetoxy-11beta-hydroxy-androsta-1,4-diene-3-one-17beta-carboxylate, code-named: BNP-166) has been prepared in a 3-step synthesis from prednisolone as starting material. The primary aim of the present work was to develop HPLC methods for the separation of all the impurities found in experimental pilot plant batches of BNP-166 at concentrations > or = 0.10 area %. Besides BNP-166, a total of 19 compounds, eight of them potential impurities, were involved in the HPLC studies in which several HPLC systems were examined and tested to optimize the separation. Of the parameters influencing chromatographic behaviour column type, the nature and composition of the mobile phase and column temperature were varied, while the pH of the eluent was kept constant at 4.5, a pH value at which stability of the BNP-166 ester bonds was found to be the highest. A comparison of the RRT values obtained allowed some conclusions to be drawn concerning the physico-chemical forces governing separation. The isocratic reversed-phase HPLC system (V02) chosen to be used for various GXP studies on BNP-166 affords baseline separation of nearly all the compounds concerned, and also the quantitation of the drug candidate (BNP-166). By means of this system, it was shown that the target compound prepared by the standardized synthesis method on a pilot plant scale, never contained more than 2-3 impurities with area % values higher than 0.10.  相似文献   
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Antigranulocyte antibodies were studied in patients with systemic lupus erythematosus. The frequency and type of the antibodies were identified with ELISA (Enzyme-Linked Immunosorbent Assay) and MGCT (microgranulocytotoxicity test). To check antibody specificity, a LCT (lymphocytotoxicity test) was used parallel with the above technique. The ELISA proved to be suitable for determining antigranulocyte antibodies. There was a correlation between the serum level of IgG-type antigranulocyte antibodies and granulocytopenia, but the IgM-type antigranulocyte antibodies failed to show a similar correlation. A good parallelism was found between MGCT--a test to be used to determine IgM-type antibodies--and the IgM-type antigranulocyte antibodies determined by ELISA. Of 25 SLE sera, 13 were found positive for antigranulocyte antibodies. LCT was used to examine the presence of HLA antibodies in these sera and 39% of the sera positive for antigranulocyte antibodies appeared to be granulocyte-specific while 61% reacted in the LCT, too.  相似文献   
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