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Postprandial blood pressure reductions have been observed in frail elderly individuals. This study evaluated blood pressure and heart rate changes in 10 healthy elderly subjects at intervals before and after a morning meal. Subjects did not exhibit significant reductions in systolic blood pressure or increases in heart rate over time, rather, such changes were due to variation within subjects. They did not exhibit significant changes in diastolic blood pressure. Age, health, and meal choice may have influenced results. Further research will determine which groups of elderly are most at risk for postprandial blood pressure reductions and consequently at risk for injury from falls due to dizziness and syncope.  相似文献   

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In dogs, transection of the gastric wall at the level of incisura angularis, followed by end--to--end anastomosis, was made. The electrodes were implanted into the muscle wall of the two stomach segments. Electrical activity of the stomach wall on the 1st postoperative day showed dissociation in the spike activity between the two segments. 10 days later, first signs of sequence in the spike activity of the stomach above and below the anastomosis appeared. Microscopic examination revealed that regenerating nerve fibers formed a bridge over the scar. On the 16th day, groups of spike potentials from the gastric wall above the section propagated also in the stomach region below the anastomosis. Since the 14th day, the microscopic examination revealed newly formed synaptic endings on the ganglionic cells distal to the scar. After the 20th day, all signs of dissociation began to disappear.  相似文献   

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Functional impairment of the vagotomized stomach used as a substitute oesophagus seriously deteriorates the quality of life of patients following oesophageal cancer surgery. We speculated that if the enteric neurons of the reconstructed gastric tube survived functionally, the motility of the gastric tube could be facilitated and the recovery process after operation would improve as a consequence. In the present study we investigated whether direct electrical stimulation was effective for facilitating the motility of the canine vagotomized stomach. Dogs underwent truncal vagotomy by transabdominal approach and, in some cases, arteries to the upper stomach and the oesophagus were also ligated and resected to resemble the blood supply and surgical invasion of the reconstructed gastric tube. Electrical stimulation, a few minutes of positive rectangular current pulses, amplitude 20 V (or 15 mA), duration 0.5 ms and frequency between 0.2 and 7 Hz, was delivered on the greater curvature of the mid corpus. Changes in mechanical contractions were recorded using strain gauge force transducers. Electrical stimulation successfully enhanced the mechanical force of the phasic ring contractions of the vagotomized stomach in a frequency dependent manner. Aboral propagation and periodicity of the contractions, impaired by surgical procedures, were restored during stimulation. These excitatory effects were inhibited by atropine, hexamethonium and tetrodotoxin, suggesting that electrical stimulation acts on intramural cholinergic nerves that have survived functionally. These results suggest that electrical stimulation could be an effective method for improving the motility of the vagotomized stomach.  相似文献   

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The present study investigated the effect of monounsaturated fatty acids (MUFA) on postprandial coagulation factor VII activity. Fifteen healthy male volunteers consumed three meals containing equal amounts (40 g) of fat, but providing different proportions of MUFA (12, 17 and 24% energy) in random order. Fasting and postprandial blood samples were drawn every hour for 9 h. The magnitude of the postprandial triacylglycerolaemic response and the postprandial plasma non-esterified fatty acid (NEFA) concentrations were not significantly different following the three meals. Coagulation factor VII was activated during postprandial triacylglycerolaemia but the area under the curve of postprandial coagulation factor VII activity was not significantly different following the three meals. Regression analysis showed that fasting factor VII activity was the single most important factor affecting postprandial factor VII activity, irrespective of plasma lipid concentrations and meal fat composition. Peak postprandial factor VII activity was attained significantly earlier following the high-MUFA meal compared with the low-MUFA meal (6.33 (SD 2.16)h, 3.60 (SD 1.81)h respectively; P = 0.016). Regression analysis showed that meal MUFA content was the primary determinant of time to peak postprandial factor VII activity. Although the magnitude of postprandial coagulation factor VII activity was not affected by meal MUFA content, peak postprandial factor VII activity occurred earlier and fasting activity levels were quickly restored following the high-MUFA meal. A short-lived increase in factor VII activity may be more beneficial than a prolonged thrombotic response.  相似文献   

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The dynamics of the spontaneous electrical activity of the rostral, dorsal, ventral and caudal claustrum was studied chronically in 12 dogs with biologically significant distinctions in the physiological state of the animals: extinction of orientative reflexes, replacement of the feeding conditions for the acid and defensive situation and elaboration of internal inhibition. The obtained data correlated with the hypothesis on an intermediate position of the claustrum between the cortex and subcortex and permit expressing a suggestion on availability in this nucleus of special representations for different physiological activities, in particular--orientative, feeding, rejecting and defensive. The ventral claustrum seems to take a maximal part in the orientative behaviour, the rostral and caudal claustrum--in the feeding behaviour, and the dorsal and ventral parts of the nucleus--in the rejecting and the defensive behaviour.  相似文献   

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A successful method for screening pupils for scoliosis in a metropolitan public school system is outlined. The incidence of scoliosis increased to greater than 3% in the seventh-grade population. Approximately 15% of the patients with established diagnoses required active management.  相似文献   

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A novel chitinase gene was isolated from Metarhizium anisopliae grown in a medium containing chitin as the sole carbon source. Comparisons of nucleotide sequence of the isolated gene with those of other fungal chitinase genes showed low sequence identity (24.4-36.4%) except for the active site of chitinase. In addition, molecular mass determination of the fused gene product separated on a gel showed that the fused chitinase seems to be about 70 kDa, while the molecular mass calculated from the deduced amino acid sequence can be about 58 kDa. These molecular masses were different from values of 33 kDa for an endochitinase and 110 kDa for an exochitinase (N-acetylglucosaminidase) from M. anisopliae published previously.  相似文献   

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This study examined whether patients with posttraumatic stress disorder (PTSD) related to motor vehicle accidents (MVAs) would show an abnormal pattern of electroencephalographic (EEG) alpha asymmetries, which has been proposed for particular types of anxiety. Patients with PTSD (n = 22) or subsyndromal PTSD (n = 21), traumatized controls without PTSD (non-PTSD with MVA; n = 21), and healthy controls without MVA (n = 23) underwent measurement of EEG activity during baseline and exposure to a neutral, a positive, a negative, and an accident-related picture. Differences in brain asymmetry between groups were observed only during exposure to trauma-related material. PTSD and subsyndromal PTSD patients showed a pattern of enhanced right anterior and posterior activation, whereas non-PTSD with MVA participants showed the opposite pattern. Furthermore, posterior asymmetry in nontraumatized healthy controls varied with gender, with female participants showing a pattern of higher right posterior activation. The results support the hypothesis that symptomatic MVA survivors are characterized by a pattern of right hemisphere activation that is associated with anxious arousal and symptoms of PTSD during processing of trauma-specific information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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An acknowledged weakness of current testing programmes for genotoxic hazard has been the potential insensitivity of the established mouse bone marrow micronucleus test and rat liver unscheduled DNA synthesis (UDS) assays to direct-acting or short-lived mutagens, which may be consumed at the site of initial contact. In such cases, in vivo test systems sampling tissues such as the skin or the stomach would provide valuable data. To test these principles a stomach UDS assay was evaluated using the potent locally active mutagen 1-chloromethylpyrene (1-CMP). Contrary to expectations, no UDS response was observed 16 h following 1-CMP dosage by oral gavage. To confirm the integrity of the 1-CMP used for the stomach UDS assay, a sample of the stored chemical was re-evaluated in vitro and shown to be still strongly positive in the Ames assay and to have alkylating activity at least 15 min after incubation at stomach acid pH. No UDS response was observed when test dose levels were reduced or when earlier sampling times were used. Other genotoxic endpoints were examined in stomach. 32P-Postlabelling analysis revealed high levels of adduct formation in gastric DNA. An assay utilizing electrophoresis of DNA (the comet assay) showed the occurrence of DNA damage following dosing with 1-CMP in vivo. These positive results confirmed that 1-CMP should be regarded as a potential in vivo genotoxin. The failure to detect a UDS response to 1-CMP in stomach was investigated; a strong UDS response was observed in an in vitro hepatocyte UDS assay of 1-CMP indicating that the rat was capable of repairing 1-CMP-derived DNA adducts. Pretreatment of rats with hydroxyurea depressed the level of incorporation of thymidine into DNA both in negative and positive [methyl-N-nitrosoguanidine (MNNG)] controls. The results of these studies indicated that the protease digestion method employed did not selectively or efficiently sample those cells with any UDS response to 1-CMP or MNNG, and the activity seen for the latter was most likely due to the presence of S phase cells within the digests. As a result of the finding that UDS responses were not demonstrated for the potent direct-acting mutagens 1-CMP and MNNG, the protease digestion/scintillation method for stomach UDS does not appear to have general value in a screening programme for locally active genotoxic agents.  相似文献   

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The histologic changes induced by irradiation of the stomachs of dogs were examined one hour to nine months after irradiation. The irradiated area of the stomach progressed to ulcer formation by way of hyperemia and erosion; on the other hand, there were simultaneous signs of recovery. Regenerating epithelium appeared during the first week and migrated from the surface adjacent to the ulcer to the center of the ulcer. Subsequently the muscularis mucosae extended, and then the submucous coat was repaired. Regeneration of the nerve fibers around the muscularis mucosae seemed to reach its maximum three weeks after irradiation. These proliferating nerves degenerated with deepening of the radiation ulcer, but they were unexpectedly radioresistant and protrude from the surface of the ulcer into the necrotic surrounding tissues. It is concluded that the effect of irradiation on the alleviation of the pain of stomach cancer is not due to the degeneration of the nerves but to elimination of the stimulation of nerves on account of the radiation effect on the cancer cells themselves.  相似文献   

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We separated mechanical and electrical activity during ischemia and we assessed the contribution of each of these variables to ischemia induced cellular electrical uncoupling. In two groups of rabbit papillary muscles, mechanical and electrical activity at the onset of ischemia was abolished. We determined how this affected the time of onset of uncoupling. Also, action potential duration (APD80), conduction velocity and extracellular pH were recorded. In the first group, the BDM group, mechanical arrest was achieved with 10 mM BDM (2,3-butanedione monoxime). This had no effect on APD80 and conduction velocity. In the second group, the quiescent group, electrical as well as mechanical arrest was obtained by not stimulating the muscles. The effect of electrical arrest was estimated as the difference between this group and the BDM group. Mechanical arrest delayed uncoupling significantly (control: 14.6 +/- 0.9 (min), mean +/- S.E.M., n = 10; BDM: 19.3 +/- 1.1, n = 10; P < 0.025). Electrical arrest caused an even greater delay (quiescent: 41.6 +/- 4.6, n = 7; P < 0.001 v control and BDM). In the BDM group, these effects were not associated with a difference of APD80 during ischemia, but with a smaller decrease of conduction velocity. Delay of uncoupling correlated with delay of extracellular acidosis. We conclude: (1) mechanical and electrical activity both are significant determinants of ischemia induced uncoupling; (2) delay of uncoupling is associated with delay of extracellular acidosis, indicating a reduced rate of metabolism.  相似文献   

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The cycle of events which leads to an impairment of the immune response in the malnourished child includes poverty, food deprivation and frequent infections. It is of great significance, however, that the marked suppression of the immune response can be repaired reasonably promptly, if the disease commences after the child has attained 1 year of age. Prenatal infection not only generates growth retardation but also a higher maternal to foetal IgG ratio, higher IgM in the neonate and a sustained immune depression. Passive cutaneous anaphylaxis measurements in the baboon skin and specific IgE determinations reveal that the elevated IgE in PEM is due to parasitic infestation and common allergens and has little or no relationship with decreased T-cell function.  相似文献   

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BACKGROUND: Bovine immunoglobulin concentrate (BIC)-Clostridium difficile is prepared from the colostrum of cows immunised against C difficile toxins and contains high concentrations of neutralising IgG antitoxin. AIMS: To determine the proportion of BIC-C difficile which survives passage through the human stomach and small intestine. METHODS: Six volunteers with an end ileostomy took 5 g of BIC-C difficile containing 2.1 g of bovine IgG on four occasions: alone, with an antacid, during treatment with omeprazole, and within enteric coated capsules. RESULTS: When BIC-C difficile was taken alone, a mean (SEM) of 1033 (232) mg of bovine IgG was recovered in the ileal fluid representing 49% of the total ingested dose. Bovine IgG recovery was not significantly increased by antacid (636 (129) mg) or omeprazole (1052 (268) mg). The enteric capsules frequently remained intact or only partially opened in the ileal effluent and free bovine IgG levels were low in this treatment group (89 (101) mg). Bovine IgG recovery was higher in volunteers with shorter (less than two hours) mouth to ileum transit times (68% versus 36%, p<0. 05). Specific bovine IgG against C difficile toxin A was detected in ileal fluid following oral BIC. Toxin neutralising activity was also present and correlated closely with bovine IgG levels (r=0.95, p<0. 001). Conclusion: BIC-C difficile resists digestion in the human upper gastrointestinal tract and specific anti-C difficile toxin A binding and neutralising activity was retained. Passive oral immunotherapy with anti-C difficile BIC may be a useful non-antibiotic approach to the prevention and treatment of C difficile antibiotic associated diarrhoea and colitis.  相似文献   

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To determine the effect of chewing sugar-free gum on caries incidence, the authors conducted a randomized clinical study. A total of 1,402 children in Puerto Rico, in grades 5 through 7 at baseline, completed the study. They were randomized by classroom into a control group or chewing gum group; those in the gum group were instructed to chew sugar-free gum for 20 minutes after each of three meals a day. Clinical and radiographic evaluations were performed at baseline and after two and three years. The results show that all subjects and high-risk subjects, respectively, in the gum group developed 7.9 percent and 11.0 percent fewer decayed, missing or filled surfaces than subjects in the control group. Based on these findings, the authors concluded that chewing sorbitol-based sugar-free gum after eating significantly reduces the incidence of dental caries.  相似文献   

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Non-invasive modalities (ultrasound, computerized tomography, MRI and somatostatin receptor scintigraphy) often fail to localize insulinomas smaller than 1.5 cm in diameter. Recently, regionalization of such occult insulinomas was facilitated by the arterial stimulation and venous sampling (ASVS) technique, using calcium as the insulin secretagogue. However, so far experience with this technique has been limited to a few tertiary referrals centres worldwide. In these case studies we report our experience in three consecutive patients with occult insulinomas. Three consecutive patients (all men 34, 51 and 56 years of age) with insulin-mediated hypoglycaemia were studied. Diagnosis of insulin hypersection was established by the finding of a high amended insulin: blood sugar ratio during fasting. Localization of a pancreatic mass lesion was unsuccessful by ultrasound, CT and/or MRI in all patients. Two patients had negative octreotide scans. In all patients after the infusion of calcium sequentially into the gastroduodenal, splenic and the superior mesenteric arteries, insulin levels rose significantly in right hepatic vein samples giving rise to diagnostic gradients from the splenic artery (in 2 patients) and gastroduodenal artery (in 1 patient), regionalizing insulinomas in the tail and head or neck of the pancreas respectively. The simultaneously obtained angiogram was positive in only 1 patient, in whom it corresponded to the insulin gradient. Regionalization of these occult tumours was subsequently confirmed at laparoscopy in the 2 patients operated. It is concluded, that the arterial stimulation venous sampling technique is an effective method in regionalizing occult insulinomas and should complement invasive angiography whenever the latter procedure is performed.  相似文献   

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