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21.
1. The effects of histamine on gastric mucosal blood flow in the presence and absence of gastric acid secretion were studied in the rat. 2. Histamine, in doses greater than those required to stimulate maximal acid secretion, caused a small increase in mucosal blood flow per unit acid output. 3. When acid secretion was inhibited by methyl analogues of prostaglandin E2, histamine reduced arterial blood pressure and gave a dose dependent rise in mucosal blood flow. 4. When acid secretion was inhibited by the histamine H2-receptor antagonists, burimamide and metiamide, histamine still increased mucosal blood flow. 5. The use of H1-receptor antagonists to inhibit the histamine-induced hyperaemia was made difficult by their vasodilator actions. 6. The selective histamine H2-receptor agonist, 4-methyl histamine, had no effect on arterial blood pressure in doses which stimulated acid secretion. The increase in mucosal blood flow which accompanied the stimulation of acid secretion was inhibited by the anti-secretory prostaglandins and H2-receptor antagonists. 7. The selective histamine H1-receptor agonist, 2-pyridyl ethylamine, had no effect on acid output but increased resting mucosal blood flow. 8. These results suggest that histamine H2-receptors, primarily concerned with acid secretion, and H1-receptors concerned with vasodilatation are both present in the rat gastric mucosa.  相似文献   
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Covalently attached, non-leaching biocidal-moieties are being explored as an environmentally friendly option for replacing antimicrobial coatings that release biocides. This review highlights studies on antimicrobial surface treatments and coatings in which the antimicrobial agent is covalently bound (i.e. tethered) to the surface or coating matrix. In addition, test methods for measuring antimicrobial surface activity are reviewed, and a discussion of advantages and disadvantages of the various methods is provided.  相似文献   
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Excretion was studied of catecholamines and diphenilamine (DOPA) in 310 patients with carcinoma of the stomach and large intestine and 43 patients with non-malignant diseases. The oncological patients showed decrease in activity of the mediator link of the sympathoadrenal system (SAS) as well as its reserves but there was no association with sex, age, location or histological structure. Three types of SAS functioning were identified, such as compensation, overstrain and emaciation. Surgical intervention led to activation of the hormonal link and exhaustion of the system's reserves. Two kinds of sympathoadrenal response to stress were described--adequate and inadequate. In the former type, phases of stress remain as they are, unchanged, as are time periods of formation thereof, while under the latter one time periods of the phases formation or formation thereof get disordered.  相似文献   
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Human chorionic gonadotropin (hCG) inhibits the progression of 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary carcinomas. In order to determine whether this phenomenon was mediated by induction of programmed cell death or apoptosis, 45-day-old virgin Sprague-Dawley rats received 8 mg DMBA/100 g body weight; 20 days later they were injected daily with 100 IU hCG for 40 days (DMBA + hCG group). Age-matched untreated, hCG- and DMBA + saline treated rats were used as controls. Tissues were collected at the time of DMBA administration and at 5, 10, 20 and 40 days of hCG injection. RNA from mammary glands, adenocarcinomas and ovaries was probed for transforming growth factors (TGF) alpha and beta, and the apoptotic genes TRPM2, ICE, bcl2, bcl-XL, bcl-XS, p53 and c-myc. The mammary glands of hCG-treated animals with or without DMBA exhibited elevated expression of TRPM2, ICE, bcl-XS, c-myc and p53; and elevation in the apoptotic index. Mammary adenocarcinomas developed in those animals treated with hCG showed an elevation in the expression of p53, c-myc and ICE genes in comparison with the levels detected in the adenocarcinomas developed by the animals treated with DMBA alone. No significant alterations in the expression of any of the genes tested was observed in ovarian RNAs. These results led us to conclude that hCG induces programmed cell death in the mammary gland initiated in the carcinogenic process, that this process is p53 dependent, and is modulated by c-myc expression. Our data also indicate the possibility that a cell death program dependent on the bcl2 family exists, because of the potential involvement of p53, bcl-XS and Bax in apoptosis. This additional mechanism of tumor inhibition makes hCG treatment a useful approach for the prevention and therapy of breast cancer.  相似文献   
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A method is presented for the quantification of haddock in complex food matrices based on real-time PCR. The proportion of haddock muscle tissue to the numbers of a single copy gene has been shown to remain relatively constant, throughout the year and across a number of fishing grounds, using conventional muscle nitrogen content as a comparator. This indicates that quantification of fish, based upon nitrogen content or the numbers of a single copy gene, would return data with a similar degree of accuracy. Thus, a haddock-specific, real-time PCR primer and probe set was designed and optimised, and when used in conjunction with a haddock calibration curve was shown to be able to quantify model samples to within 7% of the true percentage. This is the first report of a real-time assay for the quantification of white fish, which would allow enforcement of the legislation in a complex food matrix containing haddock with other fish species.  相似文献   
28.
The multiple benefits of water reuse have yet to be fully realized in our urban water management systems. One pathway to optimal implementation is to plan for their integration with wider assets in water resource or drainage and wastewater management plans. This paper explores the perspectives of water resource and wastewater management planners. Qualitative data was gathered from a workshop organized by the Chartered Institution for Water and Environmental Management (CIWEM) with 25 participants from England's Water Service Providers (WSPs), regulators (Ofwat and the Environment Agency) and consultants working within the UK water sector. The participants acknowledged that water reuse is relevant to both water resource and drainage and wastewater management planning, but that current regulatory and funding frameworks are constraining effective engagement between water resource and drainage and wastewater management planners by encouraging the development of separate plans. A general consensus of the participants was that it would be beneficial to include water reuse technology within current and future Water Resource Management Plans (WRMPs) and Drainage and Wastewater Management Plans (DWMPs). Participants suggested this could be developed through collaborative working partnerships and support from regulatory and funding frameworks that allow for the growth and development of innovative technologies and nature-based solutions. Participants also highlighted a stronger economic case could be made for water reuse technologies if the approach seeks to capture the wider benefits and not only the ‘best value’ solution. Societal acceptance and the availability of good quality data will be key to the successful adoption of any incentivized water reuse schemes.  相似文献   
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A range of tests of everyday attention is described, based on ecologically plausible activities such as searching maps, looking through telephone directories, and listening to lottery number broadcasts. An age-, sex- and IQ-stratified sample of 154 normal participants was given these tests, along with a number of existing tests of attention. The factor structure revealed by this data set matched well contemporary evidence for a set of functionally independent attentional circuits in the brain, and included factors for sustained attention, selective attention, attentional switching and auditory-verbal working memory. The Test of Everyday Attention (TEA), which was developed and standardized on the basis of these subtests, has three parallel forms, high test-retest reliability, and correlates significantly with existing measures of attention. Furthermore, selected subtests successfully discriminate among a number of brain-impaired groups, including closed head injury versus age-matched controls, minimal versus mild Alzheimer's disease, and progressive supranuclear palsy patients versus age-matched controls.  相似文献   
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