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排序方式: 共有797条查询结果,搜索用时 15 毫秒
11.
Shah P. M. Boulos P. B. Springall R. Vashisht R. Pearce F. L. 《Inflammation research》1994,41(1):C51-C52
The H2-antagonists famotidine and nizatidine produced a dose-dependent inhibition of histamine release from human colonic mucosal and muscle mast cells stimulated with anti-IgE. The IC30 values were in the range 0.5–10 μM and the maximum inhibition approached 50%. The compounds showed similar efficacy against rat peritoneal mast cells but were more potent. The cytoprotectant misoprostol had a striking effect on the human colonic mast cells, producing more than 50% inhibition at concentrations of 0.1–1 nM, but was much less active against the rat cells.
相似文献12.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background. 相似文献
13.
Determination of malondialdehyde-induced DNA damage in human tissues using an immunoslot blot assay 总被引:3,自引:4,他引:3
Leuratti C; Singh R; Lagneau C; Farmer PB; Plastaras JP; Marnett LJ; Shuker DE 《Carcinogenesis》1998,19(11):1919-1924
Malondialdehyde (MDA) is a product of lipid peroxidation and prostaglandin
biosynthesis. It is mutagenic and carcinogenic and the major adduct formed
by reaction with DNA, a highly fluorescent pyrimidopurinone (M1-dG), has
been detected in healthy human liver and leukocyte DNA. Analytical methods
used so far for the detection of M1- dG have not been applied to a large
number of individuals or variety of samples. Often, only a few microg of
DNA from human tissues are available for analysis and a very sensitive
assay is needed in order to detect background levels of M1-dG in very small
amounts of DNA. In this paper, the development of an immunoslot blot (ISB)
assay for the measurement of MI-dG in 1 microg of DNA is described. The
limit of detection of the assay is 2.5 adducts per 10(8) bases. A series of
human samples were analysed and levels of 5.6-9.5 (n = 8) and 3.1-64.3 (n =
42) of M1-dG per 10(8) normal bases were detected in white blood cell and
gastric biopsy DNA, respectively. Results on four human samples were
compared with those obtained using an HPLC/32P-post- labelling (HPLC/PPL)
method previously developed and indicated a high correlation between M1-dG
levels measured by the two assays. The advantages of ISB over other assays
including HPLC/PPL, such as the possibility of analysing 1 microg
DNA/sample and the fact that it is less time-consuming and laborious, means
that it can be more easily used for routine analysis of a large number of
samples in biomonitoring studies.
相似文献
14.
Nicole Fakhoury Sayegh Gessica N. H. A. Heraoui Hassan Younes Lea Nicole Sayegh Christa Boulos Raymond Sayegh 《Nutrients》2022,14(12)
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis. 相似文献
15.
16.
Calligaro KD Toursarkissian B Clagett GP Towne J Hodgson K Moneta G Sidawy AN Cronenwett JL;Clinical Practice Council Society for Vascular Surgery 《Journal of vascular surgery》2008,47(1):1-5
The Clinical Practice Council of the Society for Vascular Surgery (SVS) was charged with providing an updated consensus on guidelines for hospital privileges in vascular and endovascular surgery. One compelling reason to update these recommendations is that vascular surgery as a specialty has continued to evolve with a significant shift towards endovascular therapies. The Society for Vascular Surgery is making the following four recommendations concerning guidelines for hospital privileges for vascular and endovascular surgery. First, anyone applying for new hospital privileges to perform vascular surgery should have completed an Accreditation Council for Graduate Medical-accredited vascular surgery residency and should obtain American Board of Surgery certification in vascular surgery within 3 years of completion of their training. Second, we reaffirm and provide updated recommendations concerning previous established guidelines for peripheral endovascular procedures, thoracic and abdominal aortic endograft replacements, and carotid artery balloon angioplasty and stenting for trainees and already credentialed physicians who are adding these new procedures to their hospital credentials. Third, we endorse the Residency Review Committee for Surgery recommendations regarding open and endovascular cases during vascular residency training. Fourth, we endorse the Inter-societal Commission for Accreditation of Vascular Laboratories (ICAVL) recommendations for noninvasive vascular laboratory interpretations and examinations to become a registered physician in vascular interpretation (RPVI) or a registered vascular technologist (RVT). 相似文献
17.
Maged N. Kamel Boulos James T. Wilson Kevin A. Clauson 《International journal of health geographics》2018,17(1):25
A PubMed query run in June 2018 using the keyword ‘blockchain’ retrieved 40 indexed papers, a reflection of the growing interest in blockchain among the medical and healthcare research and practice communities. Blockchain’s foundations of decentralisation, cryptographic security and immutability make it a strong contender in reshaping the healthcare landscape worldwide. Blockchain solutions are currently being explored for: (1) securing patient and provider identities; (2) managing pharmaceutical and medical device supply chains; (3) clinical research and data monetisation; (4) medical fraud detection; (5) public health surveillance; (6) enabling truly public and open geo-tagged data; (7) powering many Internet of Things-connected autonomous devices, wearables, drones and vehicles, via the distributed peer-to-peer apps they run, to deliver the full vision of smart healthy cities and regions; and (8) blockchain-enabled augmented reality in crisis mapping and recovery scenarios, including mechanisms for validating, crediting and rewarding crowdsourced geo-tagged data, among other emerging use cases. Geospatially-enabled blockchain solutions exist today that use a crypto-spatial coordinate system to add an immutable spatial context that regular blockchains lack. These geospatial blockchains do not just record an entry’s specific time, but also require and validate its associated proof of location, allowing accurate spatiotemporal mapping of physical world events. Blockchain and distributed ledger technology face similar challenges as any other technology threatening to disintermediate legacy processes and commercial interests, namely the challenges of blockchain interoperability, security and privacy, as well as the need to find suitable and sustainable business models of implementation. Nevertheless, we expect blockchain technologies to get increasingly powerful and robust, as they become coupled with artificial intelligence (AI) in various real-word healthcare solutions involving AI-mediated data exchange on blockchains. 相似文献
18.
Local eradication of rat colon cancer with photodynamic therapy: correlation of distribution of photosensitiser with biological effects in normal and tumour tissue. 总被引:1,自引:0,他引:1 下载免费PDF全文
Photodynamic therapy is a photochemical technique for the local destruction of tumours, entailing the interaction of light with an administered photosensitiser to produce a cytotoxic effect. We investigated the tissue distribution of the photosensitiser aluminium sulphonated phthalocyanine (AlSPc) in dimethylhydrazine induced colonic tumours and adjacent normal colon in rats. Forty eight hours after intravenous injection, most tumours contained twice as much AlSPc as normal colon. Tumour size and position in the colon did not affect AlSPc concentration. Microscopic fluorescence localisation of AlSPc showed significant photosensitiser accumulation in tumour stroma, whereas tumour and normal mucosa contained similar amounts. Thus, some normal tissue damage, where malignant cells invade normal areas, would inevitably accompany eradication of tumours. Tumour destruction and healing of colon after tumour eradication were examined histologically. There was sharp demarcation between necrotic areas (tumour or normal) and adjacent tissue and, whether the treated area was tumour or normal, healing occurred by regeneration of normal tissue. Some incompletely eradicated large tumours showed evidence of delayed bleeding. The possibility of selective uptake or preferential retention of the photosensitiser in tumours formed the initial basis for investigation of photodynamic therapy, but it is now clear that this is seldom the most important factor for tumour eradication. Of far greater importance is the nature of the biological effect of photodynamic therapy as necrosis of small tumours involving the full thickness of the bowel wall can be achieved with safe healing by regeneration of normal colon. The maximum depth of necrosis produced was only a few millimetres, so this technique is unlikely to be of value as the primary treatment for large colonic tumours but may prove of value for eradicating small lesions or as adjunctive therapy for eradication of small nests of tumour remaining or recurring in the tumour bed after conventional surgery. 相似文献
19.
Minasian LM; Szatrowski TP; Rosenblum M; Steffens T; Morrison ME; Chapman PB; Williams L; Nathan CF; Houghton AN 《Blood》1994,83(1):56-64
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites. 相似文献
20.
Kushwaha RS Hayne D Vaizey CJ Wrightham E Payne H Boulos PB 《Diseases of the colon and rectum》2003,46(9):1182-1188
INTRODUCTION: The effect of pelvic radiotherapy on anorectal function is not clearly documented and is investigated in this prospective study. METHODS: Thirty-one males (median age, 70 years) with carcinoma of the prostate (n = 28) and bladder (n = 3) completed proctitis/incontinence symptom score questionnaires and anorectal physiology studies before and six weeks after pelvic radiotherapy. At six months after completion of radiotherapy, 25 of these patients were studied again. The results were expressed as medians and ranges and compared by the Mann-Whitney U test (2-tailed). RESULTS: Six weeks and six months after treatment, respectively, the proctitis symptom scores (0 (0-4) vs. 2 (0-7) (P < 0.001) vs. 2 (0-5) (P < 0.001)) and the incontinence symptom scores (0 (0-5) vs. 4 (0-11) (P < 0.001) vs. 3 (0-14) (P < 0.001)) increased. Urgency, frequency of defecation, anorectal pain, incontinence to liquid stool and to flatus, and alteration in lifestyle were significant symptoms after treatment. The following measurements decreased: anal canal resting pressure (83 (35-137) vs. 79 (26-152) (P = NS) vs. 71 (29-97) (P < 0.01) cm H2O), the squeeze increment (152 (51-135) vs. 162 (63-321) (P = NS) vs. 108 (45-296) (P < 0.042) cm H2O), and the maximum tolerated rectal volume (245 (115-450) vs. 194 (112-344) (P < 0.05) vs. 200 (109-350) (P < 0.138) ml). The rectal electrosensory threshold increased (20 (5.4-44) vs. 22 (9-50.5) (P < 0.134) vs. 31.5 (13.6-76) (P < 0.001) mA). CONCLUSIONS: Anorectal symptoms at six weeks after pelvic radiotherapy are related to reduced rectal capacity and compounded at six months by diminished internal and external sphincter function and rectal mucosal sensitivity. 相似文献