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排序方式: 共有4199条查询结果,搜索用时 46 毫秒
51.
Emilie Savoye Camille Legeai Julien Branchereau Samuel Gay Bruno Riou Francois Gaudez Benoit Veber Franck Bruyere Gaelle Cheisson Thomas Kerforne Lionel Badet Olivier Bastien Corinne Antoine and the cDCD National Steering Committee 《American journal of transplantation》2021,21(7):2424-2436
Controlled donation after circulatory death (cDCD) is used for “extended criteria” donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12–1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20–2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31–2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol. 相似文献
52.
Edrophonium administered in divided doses has been reported to accelerate antagonism of neuromuscular blockade, i.e., a "priming" effect. Since measured onset times can be affected by the type of stimulation used, this effect was studied using both train-of-four (TOF) and single twitch (ST) stimulation. During thiopentone-nitrous oxide-enflurane anaesthesia 20 adults were given atracurium 0.5 mg.kg-1. Both ulnar nerves were stimulated with TOF every 12 sec until one per cent recovery of first twitch (T1). At this time, ST stimulation was applied to one arm, selected at random. When the mean value of T1 and ST reached ten per cent of control, edrophonium, 1 mg.kg-1, preceded by atropine was given either as a single dose, or in two doses consisting of 0.2 mg.kg-1 followed by 0.8 mg.kg-1 three minutes later. No statistically significant differences were observed between T1 and ST for the next ten minutes, whether edrophonium had been given in single or divided doses. Giving edrophonium in divided doses did not improve recovery significantly, measured with either T1, ST or train-of-four ratio (T4/T1). Five minutes after the first administration of edrophonium, T1 was (mean +/- SEM) 86 +/- 3 and 86 +/- 2 per cent control in the single and divided dose groups respectively. Corresponding values for ST were 89 +/- 1 and 89 +/- 2 per cent (NS), and for TOF, 49 +/- 3 and 57 +/- 3 per cent (NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
53.
Gudex C Williams A Jourdan M Mason R Maynard J O'Flynn R Rendall M 《Health trends》1990,22(3):103-108
The 'top 22' patient conditions on the general surgical waiting list at Guy's Hospital were rated independently by five general surgeons. Each surgeon estimated the peri-operative mortality rates associated with each treatment; the proportion of patients who failed to benefit; the effect of successful treatment on life expectancy and on the patients' quality of life. the mean values were used to estimate the expected net benefits (in terms of quality-adjusted life-years) from treatment one year earlier than might otherwise have been the case. These benefits were then related to the operating times and length of stay associated with each treatment; this identified which treatments offered the greatest benefit per unit of each constrained resource. Of all conditions examined anal fissures where shown to be the least resource intensive in relation to the benefits generated, whilst varicose veins and epigastric hernias proved otherwise. For the full potential of this approach to be realised it needs to be repeated in other places and in other specialties. It nevertheless offers a more rational basis for interpreting waiting list data than presently exists and by using the short-cut methods is a relatively cheap way of generating much useful data. 相似文献
54.
Cummings KM Kelly J Sciandra R Deloughry T Francois F 《American journal of health promotion : AJHP》1990,4(6):429-434
Abstract This paper presents the results of a follow-up evaluation conducted to assess the impact of a community-wide stop smoking contest conducted in Buffalo, New York in January 1988. The contest challenged smokers to make a pledge to quit jar 30 days to have a chance to win $1,000 cash, a vacation trip, or other prizes. Finalists were randomly selected and chemically tested to verify abstinence. Telephone follow-up interviews were conducted on a sample of 411 contestants six weeks and eight months after the quit date. A total of 2,565 smokers enrolled in the contest. Compared to smokers in the general population, contestants were more likely to be female, white, under age 40, and smoke 25 or more cigarettes daily. Over 90 percent of contestants attempted to stop smoking, 51 percent quit jar the 3D-day contest period, and 32 percent were not smoking after eight months. 相似文献
55.
Martin Kolev Tara Barbour Scott Baver Cedric Francois Pascal Deschatelets 《Immunological reviews》2023,313(1):358-375
C3 is a key complement protein, located at the nexus of all complement activation pathways. Extracellular, tissue, cell-derived, and intracellular C3 plays critical roles in the immune response that is dysregulated in many diseases, making it an attractive therapeutic target. However, challenges such as very high concentration in blood, increased acute expression, and the elevated risk of infections have historically posed significant challenges in the development of C3-targeted therapeutics. This is further complicated because C3 activation fragments and their receptors trigger a complex network of downstream effects; therefore, a clear understanding of these is needed to provide context for a better understanding of the mechanism of action (MoA) of C3 inhibitors, such as pegcetacoplan. Because of C3's differential upstream position to C5 in the complement cascade, there are mechanistic differences between pegcetacoplan and eculizumab that determine their efficacy in patients with paroxysmal nocturnal hemoglobinuria. In this review, we compare the MoA of pegcetacoplan and eculizumab in paroxysmal nocturnal hemoglobinuria and discuss the complement-mediated disease that might be amenable to C3 inhibition. We further discuss the current state and outlook for C3-targeted therapeutics and provide our perspective on which diseases might be the next success stories in the C3 therapeutics journey. 相似文献
56.
Karen B Jourdan Timothy W Evans Nicholas P Curzen Jane A Mitchell 《British journal of pharmacology》1997,120(7):1280-1285
- 8-Iso prostaglandin F2α (8-iso PGF2α) is one of a series of prostanoids formed independently of the cyclo-oxygenase pathway. It has been shown to be upregulated in many conditions of oxidant stress where its formation is induced by free radical-catalysed actions on arachidonic acid. As 8-iso PGF2α is formed in vivo in diseases in which oxidant stress is high such as septic shock, we have assessed the relative potency and efficacy of this compound in pulmonary arteries from control and lipopolysaccharide (LPS)-treated rats.
- Several studies have characterized the contractile actions of 8-iso PGF2α on various smooth muscle preparations, but its potential dilator actions have not been addressed. Thus these studies examined both the contractile and dilator actions of 8-iso PGF2α in rat pulmonary artery rings. The thromboxane mimetic U46619, PGE2 sodium nitroprusside (SNP) and acetyl choline (ACh) were used for comparison. Each prostanoid had to be dissolved in ethanol to a maximum concentration of 1×10−2 M. At high concentrations, ethanol directly contracted pulmonary vessels. We were therefore limited by the actions of the vehicle such that we were unable to add prostanoids at concentrations higher than 1×10−4 M. In some cases this meant that maximum responses were not achieved and in these cases the Emax and pD2 values are apparent estimates.
- The following rank order of potency was obtained from contractile studies; U46619>8-iso PGF2α>PGE2, each prostanoid producing concentration-dependent contractions (10−103×10−4 M, 10−910−4 M, 10−810−4 M, respectively). As has been shown previously for other smooth muscle preparations, the thromboxane receptor (TP) antagonist ICI 192605, (1×10−6, 1×10−5 and 1×10−4 M), inhibited the contractions of 8-iso PGF2α in a concentration-dependent fashion.
- The nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 1×10−4 M), enhanced the contractile function of both 8-iso PGF2α and PGE2, but had no effect on that caused by U46619. Similarly, L-NAME inhibited the dilator function of all agents tested except the exogenous nitric oxide (NO) donor SNP, indicating that PGE2 and 8-iso PGF2α like ACh, act through the release of NO. The specificity of the effects of L-NAME were confirmed in studies with the inactive enantiomer D-NAME (1×10−4 M), which did not affect the contractile or the dilator actions of 8-iso PGF2α. Furthermore, ICI 192605 enhanced the dilator actions of 8-iso PGF2α, suggesting that the dilator component of 8-iso PGF2α was achieved via activation of a non-TP receptor.
- Isoprostanes may modulate vascular tone by a direct action on TP receptors to cause contraction and via a distinct receptor leading to the release of NO to cause dilatation.
57.
The predictive value of basal follicle stimulating and growth hormone levels as determined by immunofluorometry during assisted reproduction 总被引:2,自引:0,他引:2
Carin Huyser Francois Le R. Fourie Johan Pentz Philip Hurter 《Journal of assisted reproduction and genetics》1995,12(4):244-251
Purpose
Our purpose was (a) to investigate relationships of baseline endocrine serum levels with selected assisted reproduction (AR) parameters and (b) to evaluate the clinical applicability of an immunofluorometric assay (IFMA) as an alternative to a radioimmunoassay (RIA).Methods Basal endocrine values (analyzed by RIA—rFSH, rLH, and rE2; analyzed by IFMA—fFSH, fLH, and fGH) were determined for female patients (n = 142) preceding ovarian stimulation for AR.Results Specific AR parameters correlated significantly with RIA- and IFMA-determined FSH levels, although IFMA correlations consistently exceeds that of RIA. Cutoff values of fFSH 11.68 IU/L or rFSH 15.0 IU/L indicated a poor response. The high-basal fFSH group was older (34 vs 31 years; P = 0.0334) and yielded fewer oocytes (2.9 vs 4.6 oocytes; P = 0.0018) than the low-basal fFSH group (<11.68 IU/L). Lower cumulative embryo scores and conception rates were also associated with the high-fFSH group, compared to the low-fFSH group.Conclusions This study confirms the negative impact of elevated basal FSH levels on AR. Basal LH, GH, and E2 levels are, in comparison to baseline FSH levels, unsuitable indices for estimating ovarian responsiveness. IFMA can be regarded as an alternative to RIA in both clinical and research laboratories. 相似文献
58.
Brett A. Trockman Jill Gerspach Roger Dmochowski Francois Haab Phillippe E. Zimmern Gary E. Leach 《The Journal of urology》1996,156(4):1418-1420
Purpose
We reviewed the urodynamic findings and treatment outcomes of a large series of men with primary bladder neck obstruction.Materials and Methods
A retrospective review was done of the presenting symptoms and urodynamic findings of 36 men with primary bladder neck obstruction. Outcomes after treatment with alpha-blockers, transurethral incision of the bladder neck and prostate, or no long-term therapy were determined by chart review and patient survey in the majority of cases.Results
Mean age of the men was 41 years. Patients had significant lower urinary tract symptoms, decreased peak urinary flow rates, elevated post-void residual, markedly elevated peak voiding pressures and poor funneling of the bladder neck during voiding. Although most patients initially chose alpha-blocker therapy, only 30 percent of those beginning alpha-blockers continued them long term, usually due to inadequate symptomatic improvement. A total of 18 men underwent transurethral incision, which resulted in significant improvements in symptom scores, peak urinary flow rates, post-void residual and peak voiding pressures. Patients reported a mean 87 percent overall improvement in symptoms after transurethral incision.Conclusions
Video urodynamics facilitate diagnosis of primary bladder neck obstruction. Transurethral incision is the most effective therapy for primary bladder neck obstruction. 相似文献59.
An immunoassay for the citrus bitter principle, naringin, and related flavonoid-7-O-neohesperidosides is reported. The assay detects ca. 2 ng of naringin and can be used to quantify this compound in the parts per billion (ppb) range in crude grapefruit juice and extracts of other plant tissues. The antiserum used is highly reactive with the 2-rhamnosyl-1-glucopyranose at the C-7 position but not with e.g. the isomeric 6-rhamnosyl-1-glucopyranose moiety and can, thus, be used to identify the stereochemistry of this disaccharide moiety at the C-7 position of flavanoids. The assay involves a directly iodinated naringin-[ (125)I] as immunotracer. 相似文献
60.
THERAPEUTIC OPTIONS: There is a need in the management of non-Hodgkin's lymphoma (NHL) for tumor-targeted therapy. Immunotherapy with monoclonal antibodies can be used to reach this goal. These treatments have however often produced disappointing efficacy and so have not been broadly applicable to patients. MODIFIED MONOCLONAL ANTIBODIES: Technological advances have been used to alter mouse monoclonal antibodies genetically, leading to the development of mouse/human chimeric or humanized antibodies with demonstrated advantages of reduced immunogenicity and enhanced ability to interact with human effector cells. Initial phase I/II trials of monoclonal antibodies for relapse or refractory NHL, especially with chimeric anti-CD20 rituximab, demonstrated encouraging results. FURTHER ASSESSMENT: Randomized trials are now necessary to compare these agents with standard regimens and to determine their optimal use. 相似文献