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101.
S. Ryan Greysen Travis Wassermann Perry Payne Fitzhugh Mullan 《Journal of general internal medicine》2009,24(12):1322-1326
INTRODUCTION
Most residents have limited education or exposure to health policy during residency. 相似文献102.
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
103.
An unusual case of colitis 总被引:1,自引:0,他引:1
104.
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep. 相似文献
105.
Laurich VM Trbovich AM O'Neill FH Houk CP Sluss PM Payne AH Donahoe PK Teixeira J 《Endocrinology》2002,143(9):3351-3360
Müllerian inhibiting substance (MIS) is produced by fetal Sertoli cells and causes regression of the Müllerian duct in male fetuses shortly after commitment of the bipotential embryonic gonad to testes differentiation. MIS is also produced by the Sertoli cells and granulosa cells of the adult gonads where it plays an important role in regulating steroidogenesis. We have previously shown that MIS can dramatically reduce testosterone synthesis in Leydig cells by inhibiting the expression of cytochrome P450 17alpha-hydroxylase/C(17-20) lyase (Cyp17) mRNA in vitro and in vivo. To characterize the signal transduction pathway used by MIS to control expression of endogenous Cyp17 in a mouse Leydig cell line, we demonstrate that MIS inhibits both LH- and cAMP-induced expression of Cyp17 at concentrations as low as 3.5 nM and for as long as 18 h. The induction of steroidogenic acute regulatory protein (StAR) mRNA by cAMP, however, was slightly increased by addition of MIS. Protein kinase A (PKA) inhibition with H-89 blocked Cyp17 mRNA induction, suggesting that MIS interferes with the PKA signal transduction pathway. Inhibition of Cyp17 induction was not seen with added U0126, and wortmannin inhibited the induction incompletely. In addition, phosphorylation of the cAMP responsive element binding protein (CREB) was not detected following 50 micro M cAMP exposure, a concentration sufficient for Cyp17 mRNA induction. Moreover, CREB phosphorylation, which was observed with addition of 500 micro M cAMP, was not inhibited by coincubation with MIS. Taken together, these results suggest that cAMP induces expression of Cyp17 by a PKA-mediated mechanism and that this induction, which is inhibited by MIS signal transduction, does not require CREB activity, and is distinct from that used to induce steroidogenic acute regulatory protein expression. 相似文献
106.
Soderberg KA Payne GW Sato A Medzhitov R Segal SS Iwasaki A 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(45):16315-16320
The adaptive immune system relies on rare cognate lymphocytes to detect pathogen-derived antigens. Na?ve lymphocytes recirculate through secondary lymphoid organs in search of cognate antigen. Here, we show that the na?ve-lymphocyte recirculation pattern is controlled at the level of innate immune recognition, independent of antigen-specific stimulation. We demonstrate that inflammation-induced lymphocyte recruitment to the lymph node is mediated by the remodeling of the primary feed arteriole, and that its physiological role is to increase the efficiency of screening for rare antigen-specific lymphocytes. Our data reveal a mechanism of innate control of adaptive immunity: by increasing the pool of na?ve lymphocytes for detection of foreign antigens via regulation of vascular input to the local lymph node. 相似文献
107.
Case finding and referral model for emergency department elders: a randomized clinical trial 总被引:8,自引:0,他引:8
Mion LC Palmer RM Meldon SW Bass DM Singer ME Payne SM Lewicki LJ Drew BL Connor JT Campbell JW Emerman C 《Annals of emergency medicine》2003,41(1):57-68
STUDY OBJECTIVE: Elderly emergency department patients have complex medical needs and limited social support. A transitional model of care adapted from hospitals was tested for its effectiveness in the ED in reducing subsequent service use. METHODS: A randomized clinical trial was conducted at 2 urban, academically affiliated hospitals. Participants were 650 community-residing individuals 65 years or older who were discharged home after an ED visit. Main outcomes were service use rates, defined as repeat ED visits, hospitalizations, or nursing home admissions, and health care costs at 30 and 120 days. Intervention consisted of comprehensive geriatric assessment in the ED by an advanced practice nurse and subsequent referral to a community or social agency, primary care provider, and/or geriatric clinic for unmet health, social, and medical needs. Control group participants received usual and customary ED care. RESULTS: The intervention had no effect on overall service use rates at 30 or 120 days. However, the intervention was effective in lowering nursing home admissions at 30 days (0.7% versus 3%; odds ratio 0.21; 95% confidence interval [CI] 0.05 to 0.99) and in increasing patient satisfaction with ED discharge care (3.41 versus 3.03; mean difference 0.37; 95% CI 0.13 to 0.62). The intervention was more effective for high-risk than low-risk elders. CONCLUSION: An ED-based transitional model of care reduced subsequent nursing home admissions but did not decrease overall service use for older ED patients. Further studies are needed to determine the best models of care for this setting and for at-risk patients. 相似文献
108.
The regulation of cholesterol side-chain cleavage enzyme (P450scc) was investigated in MA-10 tumor Leydig cells. We recently demonstrated that the constitutive and cAMP-stimulated expression of P450scc in normal mouse Leydig cells is negatively regulated by glucocorticoids. We now report that glucocorticoids have the opposite effect in MA-10 cells causing a 1.7-fold increase in the rate of P450scc synthesis and a 2.1-fold increase in the amount of P450scc mRNA. Treatment of MA-10 cells with 10 microM 8-bromo-cAMP (8-Br-cAMP) (cAMP) resulted in a 1.7-fold increase in P450scc synthesis and a 3-fold increase in P450scc mRNA. Combined treatment with dexamethasone and cAMP resulted in additive increases in synthesis (2.8-fold) and mRNA (5.3-fold). Increases in de novo synthesis and mRNA levels were reflected by modest increases in the amount of immunoreactive P450scc enzyme protein. Dexamethasone-mediated stimulation in synthesis and accumulation of P450scc mRNA were blocked by the antiglucocorticoid RU-486. Cycloheximide blocked both cAMP- and dexamethasone-induced increases but had no effect on constitutive levels of P450scc mRNA. Treatment of MA-10 cells with 10 microM 8-Br-cAMP had no effect on cell morphology and stimulated progesterone accumulation to a minor degree. Treatment of MA-10 cells with 1 mM 8-Br-cAMP resulted in cell rounding and loss of cells from culture dishes. The results of this study demonstrate that: 1) dexamethasone increases P450scc de novo synthesis and mRNA levels in MA-10 tumor Leydig cells, opposite to the effect in normal Leydig cells; 2) dexamethasone- and cAMP-stimulated increases occur via distinct mechanisms; 3) and synthesis of protein factor(s) is required to mediate the action of both dexamethasone and cAMP. 相似文献
109.
Susana Gavidia‐Payne Bianca Denny Kate Davis Andrew Francis Merv Jackson 《Clinical Psychologist》2015,19(3):111-121
The substantial focus of resilience research on childhood well‐being has resulted in limited knowledge regarding other aspects of resilience in families, such as that of parents. Informed by literature in childhood and family resilience, in this review, we progress conceptual understanding by focusing on parental resilience. The definition of parental resilience, as the capacity of parents to deliver a competent and quality level of parenting to children despite the presence of risk factors, is offered here as a worthwhile framework through which to explore variables thought to contribute to resilience among parents. A conceptual model is proposed whereby parental psychological well‐being and self‐efficacy, family functioning, and social connectedness are specifically addressed, with each posited as playing an important role in parents’ ability to deliver high‐quality parenting. In addition to these factors, how parents accommodate adversity and find meaning in their everyday lives within their families is hypothesised to be an important process in understanding parental resilience. 相似文献
110.