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21.
Pulmonary endothelium: a dynamic interface 总被引:2,自引:0,他引:2
Appreciation of the cell biology of endothelial cells has contributed greatly to understanding of endothelium as a tissue. Endothelium can no longer be considered simply as an inert barrier with fixed permeabilities, nor as an unreactive expanse of non-thrombogenic surface. Pulmonary endothelium is now recognized to be a tissue composed of metabolically active, functionally responsive cells, that interact with circulating substrates and formed elements in ways that regulate the composition of systemic arterial blood, affect target organ functions, and contribute to thrombosis, hemostasis and immune reactions. Much impetus for the new appreciation of endothelial cell structures and functions has been derived from the ability to isolate and culture pulmonary endothelial cells. Improvements in culture conditions and the growing awareness that biochemical, ultrastructural, as well as physical (fluid mechanical), considerations must be taken into account should pave the way for greater understanding of the role of the endothelium in health and disease. 相似文献
22.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
23.
Association of Hypoalbuminemia on the First Postoperative Day and Complications Following Esophagectomy 总被引:1,自引:0,他引:1
Aoife M. Ryan Aine Hearty Ruth S. Prichard Aileen Cunningham Suzanne P. Rowley John V. Reynolds 《Journal of gastrointestinal surgery》2007,11(10):1355-1360
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma
and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute
albumin level on the first postoperative day was of value in predicting in-hospital complications.
Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and
2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included
in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression
analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level.
Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative
complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22
vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications
(odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and
a return to ICU.
Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative
risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes. 相似文献
24.
25.
The incidence of neural tube defects in a rural area of the west of Ireland from 1974 to 1985 was 2.96 per 1000. The prevalence was unchanged during the 11 years. When compared with a control group there was no increased incidence of anaemia in mothers of affected infants. 相似文献
26.
M R Garcia N D Ryan H Rabinovitch P Ambrosini J Twomey S Iyengar H Novacenko B Nelson J Puig-Antich 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(3):398-406
In an effort to evaluate whether differences exist in the hypothalamic-pituitary-thyroid axis of depressed children, a thyrotropin releasing hormone (TRH) stimulation test was administered to 55 prepubertal subjects who were divided into three groups matched for age and sex: a depressed group (endogenous N = 15, nonendogenous N = 15), a psychiatric nondepressed control group (N = 16), and a normal control group (N = 9). Each subject was tested at two dosages of TRH, 2 micrograms/kg and 7 micrograms/kg. Increasing age and female sex were positively correlated with a greater thyroid stimulating hormone (TSH) response. TSH response to TRH was examined with subjects reclassified by severe suicidal ideation, severe aggression, and parental history of alcoholism. Results of this study are contrasted with the adult psychiatric literature. 相似文献
27.
Richard A. Hill Terri Esterowitz Julie Ryan Lih-Huei L. Liaw J. Stuart Nelson Hideko Yashiro Tatiana Krasieva Michael W. Berns 《Lasers in surgery and medicine》1995,17(2):166-171
Background and Objective: To investigate Photofrin® (PII) and CASPc for photodynamic therapy (PDT) of the ciliary body in rabbits. Study Design/Materials and Methods: PII (10 mg/kg) or CASPc (1 mg/kg) was given by ear vein. Pharmacokinetics were studied in frozen sections by fluorescence microscopy (CCD camera based low light detection system with digital image processing) at 1 and 24 h (8 rabbits;16 eyes). Laser light was delivered (argon pumped dye laser;630 and 675 nm;8 rabbits;16 eyes) by contact fiberoptic. To compensate for iris attenuation, irradiance was 125 mW/cm2 (20, 40, 80, or 160 J/cm2). Controls (4 rabbits;8 eyes) received laser light without photochemicals (OD) and for comparison, continuous wave Nd:YAG laser by fiberoptic (0.8–1.2J;OS). Results: Localization studies showed intravascular distribution with some selective ciliary body distribution at 24 h (PII > CASPc). Rabbits treated with PII or CASPc exhibited variable amounts of gross ciliary body edema, infarction, and necrosis by 24–48 h. This response was not seen in PDT control tissues;damage was seen in the iris and ciliary body, with partial vacuolization of the pigment epithelium. Conclusion: PDT may offer a more selective approach to ciliary body destruction. A small but significant thermal effect was seen during PDT from melanin photon uptake with damage to iris and ciliary body. Thermal damage and potential interaction with ocular visual pigments may limit use of these photochemicals and wavelengths for PDT of the ciliary body © 1995 Wiley-Liss, Inc. 相似文献
28.
Paul D. Sarvela Christine E. Cronk Fred R. Isberner 《The Journal of school health》1997,67(9):372-375
ABSTRACT: This paper compares rural and urban youth cigarette-smoking behavior using the Monitoring the Future data set, a national, probability-based, multi-stage sample design. Cigarette smoking was examined by region, race, and gender over time. Results indicated that rural White males smoked more ofen (30-day prevalence of 34%) than any other group. Urban Black males smoked the least (10%). Urban White females smoked more (30-day prevalence of 33%) than urban Black females (7%). In general, rural and urban Whites reported smoking at significantly higher rates than rural and urban Blacks. Smoking rates declined steadily for both rural and urban Black females and urban Black males over the study period. These data document distinctive patterns of tobacco use among the nation's youth, which can be used by program planners for specific targeted interventions. 相似文献
29.
V G Matassa F J Brown P R Bernstein H S Shapiro T P Maduskuie L A Cronk E P Vacek Y K Yee D W Snyder R D Krell 《Journal of medicinal chemistry》1990,33(9):2621-2629
The dissociation constants (KB) at the LTD4 receptor on guinea pig trachea of a series of monocyclic and bicyclic cyclopentylurethane and cyclopentylacetamide N-arylsulfonyl amides have been measured. The KB was found to be remarkably tolerant of changes in the electronic constitution and lipophilicity of the bicyclic ring system (template). Thus, N-[4[[6-[[(cyclopentyloxy)carbonyl]amino]benzimidazol-1- yl]methyl]-3-methoxybenzoyl]benzenesulfonamide (11a) and N-[4-[[5-[[(cyclopentyloxy)carbonyl]amino]benzo[b]thien-3- yl]methyl]-3-methoxybenzoyl]benzene-sulfonamide (25a) had closely similar affinities (pKB, 9.20 and 9.31, respectively; LTE4 as agonist). It has been shown that the hetero-ring of the template need not be aromatic in order to achieve high affinity, since indoline 31 and 2,3-dihydrobenz-1,4-oxazines 37a-c had pKBs greater than 9. Further, it has been shown that an o-aminophenone (see 42 and Figure 3) can function as a template; the template in 42 [see iii] is bicyclic by virtue of the presence of an intramolecular hydrogen bond. In contrast, when the template is a phenyl ring (48), receptor affinity is markedly reduced. These findings support the notion that central bicyclic ring system in this family of peptidoleukotriene antagonists is a molecular feature which helps to preorganize the acylamino and acidic chains and thereby facilitate the molecular recognition event. 相似文献
30.
Joyce J. Fitzpatrick Sheila Ryan DeWitt Baldwin Roger Bulger Jean Johnson-Pawlson Christopher McLaughlin Maureen Kelley Leopold Selketr Bernardine Lacey Charlene Hanson Robin Harvan Patricia Hinton Walker David Sluyter Mary Joan Ladden Neal Vanselow 《Journal of Midwifery & Women's Health》1998,43(1):61-65
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible. 相似文献