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81.
Influence of acoustic stress by noise on gastrointestinal motility in dogs   总被引:4,自引:0,他引:4  
The effects of acoustic stress (AS) on gastrointestinal motility and their prevention by previous treatment with naloxone, phentolamine, propranolol, muscimol, and diazepam were investigated in intact and vagotomized fasted dogs fitted with chronically implanted strain gauges on the antrum at 10 cm from pylorus and on the jejunum at 70 and 140 cm from the pylorus. These effects were compared to those produced by intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Beginning 40–50 min after the occurrence of a gastric migrating motor complex (MMC), a 1-hr hearing of prerecorded intense music through earpieces (<100 dB) delayed the occurrence of the next gastric MMC observed after 2.8±1.2 hr, while jejunal MMC were still present at a normal frequency. During AS, heart rate and plasma cortisol were significantly increased by 32.7 and 215%, respectively, 10–15 min after the beginning of hearing. The AS-induced lengthening of the gastric MMC cycle as well as cortisol increase were abolished after previous administration of diazepam (0.5 mg/kg intramuscular) or muscimol (10 g/kg intravenous), while they were still present after naloxone (0.1 mg/kg intravenous), phentolamine (0.2 mg/kg intravenous), or propranolol (0.1 mg/kg intravenous). CRF administered intracerebroventricularly (100 ng/kg) also delayed the occurrence of gastric MMC without affecting jejunal motility, and this effect was not antagonized by previous treatment with diazepam or muscimol. Both the effects of AS and CRF were abolished after bilateral thoracic vagotomy. These results suggest that the selective inhibition of gastric motility induced by noise in dog is due to the CNS release of CRF which affects, in turn, the vagal output to the stomach. The suppressive action of diazepam or GABA agonist on noise-induced gastric hypomotility may be related to blockade of the AS-induced CRF release.  相似文献   
82.
ObjectivesThe efficacy of thrombolytic therapy with tissue plasminogen activator (tPA) is highly time dependent. Although clinical guidelines do not recommend written informed consent as it may cause treatment delays, local policy can supersede and require it. From 2014 to 2017, three out of five public hospitals in Singapore changed from written to verbal consent at different time points. We aimed to examine the association of hospital policy changes regarding informed consent on door-to-needle (DTN) times.Materials and MethodsUsing data from the Singapore Stroke Registry and surveys of local practice, we analyzed data of 915 acute ischemic stroke patients treated with tPA within 3 hours in all public hospitals between July 2014 to Dec 2017. Patient-level DTN times before and after policy changes were examined while adjusting for clinical characteristics, within-hospital clustering, and trends over time.ResultsPatient characteristics and stroke severity were similar before and after the policy changes. Overall, the median DTN times decreased from 68 to 53 minutes after the policy changes. After risk adjustment, changing from written to verbal informed consent was associated with a 5.6 minutes reduction (95% CI 1.1-10.0) in DTN times. After the policy changed, the percentage of patients with DTN ≤60 minutes and ≤45 minutes increased from 35.6% to 66.1% (adjusted OR 1.75; 95% CI 1.12-2.74) and 9.3% to 36.0% (adjusted OR 2.42; 95% CI 1.37-4.25), respectively.ConclusionChanging from written to verbal consent is associated with significant improvement in the timeliness of tPA administration in acute ischemic stroke.  相似文献   
83.
84.
S K Lam  G B Ong 《Gut》1980,21(6):528-532
Integrated postprandial serum gastrin levels were studied in a prospective series of 144 Chinese patients with duodenal ulcer in relation to sex, total body weight, age of onset and duration of ulcer symptoms, blood group status, and positivity for familial dyspepsia. Postprandial gastrin was unrelated to sex, total body weight, duration of symptoms, and blood group status. Patients whose onset age was in the first two decades (early onset group) had significantly higher postprandial gastrin than those with onset age in the 4th and 6th decades (P less than 0.01). This was found to be associated with the presence in the early onset group (n = 35) of a high proportion of patients with positive family history of ulcer dyspepsia (n = 24), in whom postprandial gastrin was significantly higher than those without such history (P less than 0.01). These results suggest that early onset patients who are positive for family history of ulcer dyspepsia segregate to form one subgroup of duodenal ulcer. They also offer a clue that familial hypergastrinaemia may be one marker for familial duodenal ulcer.  相似文献   
85.
Background Carbohydrate antigen 19.9 (CA19.9), a tumor marker for malignancies of the hepatobiliary tract and pancreas, has frequently been shown to be deranged in a number of non-malignant conditions that are associated with jaundice. This study aims to demonstrate the correlation between CA19.9 and serum bilirubin concentration in patients with benign conditions and to determine the frequency of a false-positive increase in CA19.9 in patients being investigated for potential HPB malignancies. Methods This is a retrospective review of 83 consecutive patients presenting with an abnormal CA19.9 and radiological or clinical features suggestive of HPB malignancy subsequently shown to have benign disease. All patients were thoroughly investigated and followed up until the diagnosis of malignancy could be safely excluded. Results Serum bilirubin, sodium, lymphocyte count, neutrophil:lymphocyte ratio (NLR), β-human chorionic gonadotrophin (HCG), and age were found to correlate with CA19.9 by Pearson’s correlation (P = 0.001, P = 0.006, P = 0.006, P < 0.001, P = 0.012, and P = 0.049, respectively). In multivariate regression analysis, bilirubin was identified as an independent variable that may predict CA19.9 level (P = 0.028). Conclusion CA19.9 level is significantly influenced by serum bilirubin and elevated levels have been observed in patients with non-malignant HPB conditions. Adjusting CA19.9 according to bilirubin levels is likely to improve the specificity of this antigen in the differential diagnosis of benign and malignant HPB diseases and its reliability in the monitoring of disease response to chemotherapy.  相似文献   
86.
We studied polymyxin B resistance in 10 pairs of clinical Acinetobacter baumannii isolates, two of which had developed polymyxin B resistance in vivo. All polymyxin B-resistant isolates had lower growth rates than and substitution mutations in the lpx or pmrB gene compared to their parent isolates. There were significant differences in terms of antibiotic susceptibility and genetic determinants of resistance in A. baumannii isolates that had developed polymyxin B resistance in vivo compared to isolates that had developed polymyxin B resistance in vitro.  相似文献   
87.
88.
ObjectiveTo determine the incidence of stillbirth in women who have regular ante-natal ultrasound compared to those that have infrequent scans in a low risk population.ResultsOur study included 23,519 ‘low-risk’ deliveries spanning 2007-2011. This included 2,088 (9%) patients who had frequent ultrasound surveillance and delivery at term and 21,431 (91%) patients who did not. The overall stillbirth rate was 0.34% and 0.20% respectively which was not statistically different (p=0.31).ConclusionThere is no difference in the rate of stillbirth between patients who have more frequent ante-natal ultrasound surveillance compared with those who do not in a low risk population.  相似文献   
89.
Renal impairment is an important predictor of mortality after percutaneous coronary intervention and may increase the restenosis rate. However, the relation between restenosis and the risk of death in patients who have renal impairment remains unclear. We evaluated the incidences of repeat revascularization and mortality in patients who had renal impairment and those who did not and who received sirolimus-eluting stents or bare stents. A total of 1,080 consecutive patients treated for 1 year had available data to calculate baseline creatinine clearance. Patients received bare stents (first 6 months, n = 543) or sirolimus-eluting stents (last 6 months, n = 537) and were grouped according to the presence or absence of renal impairment (creatinine clearance <60 ml/min). Patients who had renal impairment had a higher mortality rate at 1 year (7.6% vs 2.5%, hazard ratio 3.14, 95% confidence interval 1.68 to 5.88, p <0.01), with no differences in mortality between patients who received bare stents and those who received sirolimus-eluting stents (hazard ratio 0.91, 95% confidence interval 0.49 to 1.68, p = 0.8). The incidence of target vessel revascularization decreased significantly in patients who were treated with sirolimus-eluting stents and did not have renal impairment (hazard ratio 0.59, 95% confidence interval 0.39 to 0.90, p = 0.01) and in those who had decreased renal function (hazard ratio 0.37, 95% confidence interval 0.15 to 0.90, p = 0.03). Thus, sirolimus-eluting stents compared with conventional stents decreased clinical restenosis in patients who had renal impairment. However, this benefit was not paralleled by a decrease in the risk of death in this population. It seems unlikely that restenosis could be a contributing factor that influenced the increased mortality of patients who had impaired renal function.  相似文献   
90.
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