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排序方式: 共有130条查询结果,搜索用时 15 毫秒
1.
Action of beer and its ingredients on gastric acid secretion and release of gastrin in humans 总被引:3,自引:0,他引:3
The intragastric action of beer and its known ingredients before and after fermentation on gastric acid secretion and release of gastrin was studied in healthy humans. None of 11 tested ingredients of fermented beer (2 x 500 mL, pH 5.5, given either alone or in combination) or hop extract had any significant effect. Finished beer (6 weeks old) and new beer were potent stimuli of acid output, causing 93% and 76% of the incremental maximal acid output in response to pentagastrin (6 micrograms/kg SC), respectively. Before the addition of yeast, preproducts of beer were considerably less potent. Thus, first and finished wort caused only a minor acid response which was 48% and 46% of maximal acid output. Foreign fermentation in first and finished wort is presumably the reason for the stimulatory action because glucose solutions in concentrations (11.5% wt/vol) seen in wort did not stimulate acid secretion. However, glucose solutions to which yeast was added, resulting in fermentation, were as potent stimuli of acid secretion as beer. Lyophilization of beer at pH 11.0 and dialysis (cutoff mol wt, 1000) removed the stimulatory substances. The plasma gastrin responses paralleled the gastric acid response to the different stimulants. It was concluded that (a) the addition of yeast to finished wort and the following alcoholic fermentation are the essential steps for the stimulatory action of beer on gastric acid secretion and release of gastrin; (b) carbohydrate metabolites with a molecular weight of less than 1000 are the acid-stimulatory agents in fermented beer; and (c) gastrin is the mediator of the stimulation of acid secretion because all substances that had a potent acid-stimulatory action also were potent stimuli of gastrin release. 相似文献
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Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed. 相似文献
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Egger B Chai NN Wang L French SW Büchler MW Eysselein VE 《Scandinavian journal of gastroenterology》2001,36(3):276-282
BACKGROUND: Transforming growth factor-alpha (TGF-alpha) is a key mediator of colonic mucosal protection and/or repair mechanisms in orally induced acute dextran sodium sulphate (DSS) colitis. However, it also has been suggested that TGF-alpha may contribute to malignant transformation in the colon. The aim of the studies was to determine whether TGF-alpha is needed for malignant transformation in orally induced chronic DSS colitis using TGF-alpha deficient mice (wa-1) and Balb/c mice, a strain competent in TGF-alpha. METHODS: Chronic colitis was induced by oral administration of DSS (5%) for 7 days followed by drinking water for 10 days in wa-1 and Balb/c mice (n = 20, per group). In the two subsequent cycles (7 days DSS, 10 days water) 3% DSS-water was utilized due to a high mortality in the wa-1 group. Mucosal injury severity was assessed histologically and graded (three grades). A crypt damage score (CDS) reflecting all three grades of mucosal pathology was calculated. Mucosal dysplasia and cancerous lesions were noted. RESULTS: Seven per cent of the entire colonic mucosa was completely destroyed in wa-1 animals compared to 3% in Balb/c mice (P < 0.05). The CDS was 10.2 +/- 0.4 and 4.8 +/- 0.3 in wa-1 and Balb/c mice, respectively (P < 0.05). Fifteen incidences of mucosal dysplasia were found in the 10 surviving wa-1 animals and 31 incidences were found in 20 Balb/c animals. In both groups, one fully developed adenomatous cancerous lesion was present. CONCLUSIONS: The markedly increased severity of mucosal injury in chronic induced DSS colitis in TGF-alpha deficient wa-1 mice compared to Balb/c mice further substantiates that endogenous TGF-alpha is a pivotal mediator of protection and/or healing mechanisms in the colon. The appearance of dysplastic and cancerous lesions in TGF-alpha deficient animals suggests that TGF-alpha per se is not essential for malignant mucosal cell transformation in colitis. 相似文献
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Colin VE Powell 《Journal of paediatrics and child health》2016,52(2):187-191
Acute exacerbations of asthma are very common reasons for a presentation to emergency departments. This paper focuses on defining the high‐risk group, consideration of the concept of phenotypes of acute asthma, the assessment of severe and life‐threatening exacerbations and an emphasis on the management of the more severe end of the exacerbation severity. A number of evidence‐based guidelines exist throughout the world and are all slightly different. This reflects the poor evidence base for some of those recommendations. Thus, a large variation of treatment drugs, doses and regimen are used and clearly not standardised. This paper aims to present a summary of the best evidence and discuss some of these controversies. The most important aspect of treating an exacerbation of acute asthma is to review regularly and assess response to treatment. Severe and life‐threatening episodes should be treated with early use of intravenous treatment in a stepwise manner following the local guidelines. Non‐invasive ventilation and high flow nasal cannulae delivery of oxygen in the emergency department are evolving modalities, but evidence for their use is currently limited. 相似文献
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ELIZABETH MENU GRARD CHAOUAT RADOSLAV KINSKY GENEVIVE DELAGE MILJENCO KAPOVIC M.N. THANG CHRISTIAN JAULIN PHILIPPE KOURILSKY THOMAS G. WEGMANN 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,33(2):200-211
METHOD : It is possible to induce increased fetal resorption in a number of inbred murine matings by injecting Poly (I) Poly (C12U) 3.5 days postconception, a maneuver associated with natural killer-mediated damage to the feto placental unit such as occurs in spontaneous fetal resorptions. RESULTS : We show here that alloimmunization can block this effect. In addition, maternal immune responses induced by alloimmunization against isolated mutant class I or class II, as well as by immunization with class I MHC alloantigens (Kd) transfected L cells are sufficient to restore normal fetal viability. It is not necessary that the maternal immune response be specifically directed against paternal alloantigens fr the fetal protecton to ensue, since the effect occurs in inbred matings when the mother is immunized against unrelated class I or class II alloantigens. As in previous studies conducted in the murine species, not all MHC alloimmunizations are protective. In addition, as control, immunization with a monomorphic class I MHC molecular (37), transfected L cells, sheep red blood cells or hen egg lysozyme is without effect. CONCLUSION : These results indicate that defined MHC antigens can mediate fetal protection from induced fetal resorption, and suggest that one driving force in promoting MHC antigen polymorphism in mammals is their capacity to confer protection from NK mediated fetal demise. 相似文献
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