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Influence of nutrient delivery on gut structure and function. 总被引:1,自引:0,他引:1
L E Bragg J S Thompson L F Rikkers 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):237-243
Food is an important stimulus for the growth of gastrointestinal mucosa. Gut structure is influenced by the route of nutrient administration, dietary composition and the availability of specific nutrients. The alterations in intestinal structure and function that occur when enteral nutrition is withheld suggests that the ingestion of food results in physiologic responses that are responsible for the maintenance of gut mass during the fed state. The mechanism of mucosal suppression that occurs during starvation, stress, and total parenteral nutrition is not completely understood but may involve the absence of luminal substrates, decreased pancreaticobiliary secretions and alterations in the endocrine or paracrine events that normally accompany eating, digestion, and absorption. Enterocytes prefer glutamine and ketone bodies as oxidative fuels, whereas colonocytes utilize short chain fatty acids. Although enteral delivery of nutrients is the preferred route for maintenance of intestinal mass, provision of specific nutrients and hormonal stimulation during parenteral alimentation has been shown to be important in maintaining mucosal structure and function. If not adequately maintained, the intestine becomes susceptible to a variety of injuries which may result in impaired ability to digest and absorb nutrients and loss of mucosal barrier function. 相似文献
64.
Percutaneous drainage access: a simplified coaxial technique 总被引:1,自引:0,他引:1
vanSonnenberg E; Wittich GR; Schiffman HR; Cabrera OA; Willson SA; Quinn SF; Casola G; Hayne LA; Polansky AD 《Radiology》1986,159(1):266-268
We describe an access technique that we have used in 150 nephrostomy and biliary drainage procedures and for access to some abscesses and viscera. The system provides safe coaxial access with a 22-gauge removable hub needle, which then acts as a guide wire and is replaced by an 18-gauge cannula. A major advantage is that only one guide wire is used (0.038-inch) for the entire drainage procedure. No significant complications have occurred to date with this method. 相似文献
65.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献
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D Pathirana A Nast AD Ormerod N Reytan P Saiag CH Smith P Spuls B Rzany 《Journal of the European Academy of Dermatology and Venereology》2010,24(12):1458-1467
Background The development of evidence based guidelines is a demanding and time consuming process. Therefore it is important to share the knowledge and discuss the structure of these guidelines in detail. Objectives To present a method report on the development process of the European evidence based guidelines on the systemic treatment of psoriasis vulgaris with the aim to offer guidance to other guidelines groups with lesser experience and to critically appraise the methodology of the guidelines development process. Methods The guidelines are based on the previously evaluated literature from three European national evidence based guidelines and an additional systematic search and evaluation of new literature. Further steps included a structured consensus conference and a DELPHI procedure to develop the recommendations, as well as several internal and external reviews. All steps were coordinated by the Division of evidence based medicine in cooperation with a group of methodologists. Results A total of 114 studies were included, serving as base for the efficacy chapters of the intervention. The recommendations, based on the efficacy and the level of evidence of the included studies were discussed and finally consented by the guidelines group. After subsequent reviews the guidelines were presented to the European Dermatology Forum, European Academy of Dermatology and Venereology and Union Européenne des Médicins Spécialistes for approval and published in October 2009. Conclusion The development of European evidence based guidelines requires a coordinated structure which can be achieved by the integration of an experienced group of methodologists. Nevertheless further improvements are imaginable and might be considered for an update or other European evidence based guidelines. 相似文献
68.
B A Husaini D E Sherkat R Bragg R Levine J S Emerson C M Mentes V A Cain 《Women & health》2001,34(3):35-51
PURPOSE: This study examines the predictors of breast cancer screening participation in a panel study of African American women over age 40. We examine the effect of depression, age, beliefs and concerns about breast cancer and its risk, communication with social networks regarding screening, marital status, participation in religious organizations, breast cancer family history, and participation in a breast cancer education program. METHODS: Participants were recruited from 30 African American churches, two low-income housing projects, and from a health fair at a historically African American University (N = 364). Participants were interviewed upon recruitment, and three months later. Multinomial logistic regression models are estimated to assess the relative impact of covariates on the odds of getting a mammogram while controlling for other factors. We also assess predicted probabilities of screening at specific levels of covariates. RESULTS: We find that age, marriage, an educational intervention, talking with friends, and believing that early detection can lead to cure had a positive impact on getting a mammogram between T1 and T2. In contrast, depression significantly reduces the odds of getting a mammogram. Family histories of breast cancer and church participation have no effect on rates of mammography net of other factors. 相似文献
69.
AD Cohen†‡§ J Dreiher†‡ Y Shapiro¶ L Vidavsky† DA Vardy‡§ B Davidovici J Meyerovitch† †† ‡‡ 《Journal of the European Academy of Dermatology and Venereology》2008,22(5):585-589
Background Previous reports have shown an association between psoriasis and the metabolic syndrome, but there are only a few studies on the association between psoriasis and diabetes. Objectives To study the association between psoriasis and diabetes. Methods A cross‐sectional study was performed utilizing the database of Clalit Health Services (CHS). Patients who were diagnosed with psoriasis were compared with CHS enrolees without psoriasis regarding the prevalence of diabetes. Patients with diabetes were identified using the CHS chronic diseases registry. Chi‐squared tests were used to compare categorical parameters. Logistic regression models were used for multivariate analyses. Results The study included 16 851 patients with psoriasis and 74 987 subjects without psoriasis (control patients). The proportion of diabetes was significantly higher in patients above 35 years (P < 0.05). The age‐adjusted proportion of diabetes was significantly higher in psoriasis patients as compared to the control group [odds ratio (OR), 1.38, P < 0.05] and was similar in men and women (OR, 1.32, 1.45, respectively). A multivariate logistic regression model showed that psoriasis was significantly associated with diabetes, independently of age and gender (OR, 1.58, P < 0.001). Conclusions Our study supports previous reports of an association between psoriasis and diabetes. Dermatologists taking care of patients with psoriasis should be aware of this association and advise the patients to reduce additional risk factors such as smoking, hypertension or dyslipidemia. 相似文献
70.
D. Cristopher Bragg Rick B. Meeker Barbara A. Duff Robert V. English Mary B. Tompkins 《Brain research》1999,816(2):154
The neurotoxic effects of the feline immunodeficiency virus (FIV) and FIV envelope proteins were measured in primary cultures of feline cortical neurons. Envelope protein from the FIV-PPR strain promoted neuronal swelling and death, whereas envelope protein from the FIV-34TF10 isolate produced intermediate or negligible toxicity. No effect was observed in control cultures treated with envelope protein from the Epstein–Barr virus. A concentration–effect curve showed that FIV-PPR protein produced maximal toxicity at 200 pM protein and decreased toxicity at higher concentrations, which is consistent with previous reports of the HIV-1 surface glycoprotein, gp120. These effects required the presence of low concentrations of glutamate. Using the natural host cells as targets, the effects of envelope protein and infectious virions were directly compared. All of the toxic activity could be attributed to non-infectious interactions between the viral envelope and target cells. Addition of 1 μM tetrodotoxin failed to block the effects of FIV-PPR in the presence of 20 μM glutamate. Toxicity would appear to involve two steps in which the envelope protein first sensitizes neurons through non-synaptic interactions (TTX insensitive) thereby setting the stage for enhanced synaptic activation via glutamate receptors (TTX sensitive). 相似文献