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981.
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Background:Optimizing the approach to and consent of potential organ donors maximizes patient autonomy and the availability of organs for transplants. We set out to identify modifiable factors associated with donation consent.Methods:We conducted a retrospective cohort study of consecutive adults (≥ 18 yr) referred for organ donation in Ontario between April 2013 and June 2019. We analyzed patient clinical data and demographics, data on substitute decision-makers and characteristics of the donation consent approach. Study outcomes were consent for organ donation and approach rate. We evaluated independent associations between consent and approach-and system-level factors.Results:We identified 34 837 referrals for organ donation, of which 6548 (18.8%) substitute decision-makers were approached for consent. Of these, 3927 (60.0% of approaches) consented for organ donation and 1883 (48.0% of consents) patients proceeded to be organ donors. The most common reason substitute decision-makers were not approached for consent in a case with donation potential was a late referral by the health care team (45.2%). Modifiable factors independently associated with consent included a telephone approach for consent (adjusted odds ratio [OR] 0.46, 95% confidence interval [CI] 0.35–0.58) and a collaborative approach by a physician and donation coordinator (adjusted OR 1.26, 95% CI 1.01–1.59).Interpretation:Consent for organ donation was associated with several modifiable factors. Organizations should target interventions to ensure timely referrals to organ donation organizations, increase in-person consent approaches and increase physician participation in the approach process.

Many people die on transplant waiting lists because the demand for organs outstrips supply. Almost 4500 people are on organ transplant waiting lists in Canada. Despite public support for organ donation across Canada,1 donation rates vary between 8.8 and 21.2 donors per million population, 2 and a substantial pool of potential donors is not being realized. 2,3 The identification, referral and approach of potential donors can be facilitated by policy, legislation and best practices, 3,4 although the efficacy of interventions is variable across jurisdictions.5,6 Some comprehensive interventions to increase donor numbers have not changed consent rates,7 suggesting that the consent approach process may be a target for improvement.Substitute decision-makers play an important role in the organ donation process, even in jurisdictions with donation consent registries or opt-out consent systems. Substitute decision-makers are almost always asked permission for organ donation, even when there is a registered donation consent,8 and their consent rates vary widely.9 Substitute decision-makers faced with consent decisions often do so in emotionally charged circumstances, and many do not know the explicit wishes of the patient.10 Given this context, the process of obtaining consent and the supports provided may have a substantial impact on the decision. Practices have been identified that improve consent rates from substitute decision-makers,11 and these are routinely performed by large, high-performing organ donation organizations. Several epidemiological studies have identified nonmodifiable factors associated with donation consent (e.g., race, age, socioeconomic status and education).1215 The persistent variability in consent rates suggests that other modifiable factors may influence a substitute decision-maker’s decision to consent.We aimed to identify modifiable approach-and system-level factors that were associated with positive consent for organ donation in Ontario, Canada.  相似文献   
984.
Thaparocleidus wallagonius is a monogenean parasite and a fish-borne pathogen with a worldwide distribution. The genome for Thaparocleidus wallagonius is known. Therefore, it is of interest to report the DNA motif analysis data in the 18S rDNA of Thaparocleidus wallagonius collected from the fish Wallago attu in India. This data forms a framework for an in-depth analysis of the parasite biology and development, immune evasion strategies, virulence and long-term survival within the definitive host.  相似文献   
985.
Radioligand therapies have opened new treatment avenues for cancer patients. They offer precise tumor targeting with a favorable efficacy-to-toxicity profile. Specifically, the kidneys, once regarded as the critical organ for radiation toxicity, also show excellent tolerance to radiation doses as high as 50–60 Gy in selected cases. However, the number of nephrons that form the structural and functional units of the kidney is determined before birth and is fixed. Thus, loss of nephrons secondary to any injury may lead to an irreversible decline in renal function over time. Our primary understanding of radiation-induced nephropathy is derived from the effects of external beam radiation on the renal tissue. With the growing adoption of radionuclide therapies, considerable evidence has been gained with regard to the occurrence of renal toxicity and its associated risk factors. In this review, we discuss the radionuclide therapies associated with the risk of nephrotoxicity, the present understanding of the factors and mechanisms that contribute to renal injury, and the current and potential methods for preventing, identifying, and managing nephrotoxicity, specifically acute onset nephropathies.  相似文献   
986.
Toxin–antitoxin (TA) systems are proposed to play crucial roles in bacterial growth under stress conditions such as phage infection. The type III TA systems consist of a protein toxin whose activity is inhibited by a noncoding RNA antitoxin. The toxin is an endoribonuclease, while the antitoxin consists of multiple repeats of RNA. The toxin assembles with the individual antitoxin repeats into a cyclic complex in which the antitoxin forms a pseudoknot structure. While structure and functions of some type III TA systems are characterized, the complex assembly process is not well understood. Using bioinformatics analysis, we have identified type III TA systems belonging to the ToxIN family across different Escherichia coli strains and found them to be clustered into at least five distinct clusters. Furthermore, we report a 2.097 Å resolution crystal structure of the first E. coli ToxIN complex that revealed the overall assembly of the protein-RNA complex. Isothermal titration calorimetry experiments showed that toxin forms a high-affinity complex with antitoxin RNA resulting from two independent (5′ and 3′ sides of RNA) RNA binding sites on the protein. These results further our understanding of the assembly of type III TA complexes in bacteria.  相似文献   
987.
988.
989.
The cells of the ovarian transmitting tissue of Lilium regaleare papilla shaped and form and epithelium on the placenta.Their ultrastructural organization and differentiation from1 d before to 7 d after anthesis is presented. These placentacells are typical transfer cells with a prominent secretionzone similar to that known from stylar canal cells. After anthesisthe secretion zone continues to grow by addition of vesiclefrom the numerous dictyosomes. Maximum depth of this zone isreached by day 4 after anthesis. The outer surface of the cellwall is distinctly rugged on cell maturation and the outermostlayer is corroded. The ER system undergoes transition from asmooth to a granular condition. Before anthesis there is a centralvacuole which at anthesis is reduced to a system of small vauoles.These are supplemented by autophagic vacuoles formed from theER. Such vacuoles are found near the secretion zone and mayalso fuse with the plasmalemma. The cuticle is sloughed andsecretion commences before anthesis. Accumulations of vesiclesfound in the nucleus and occasional connections between suchvesicles and the inner membrane of the nuclear envelope indicatethe presence of a nuclear network. Protein crystals are presentin the cytoplasm and the nucleus. The starch grains in the plastidsare digested after anthesis, but new ones are formed by days6 and 7.Copyright 1995, 1999 Academic Press Lilium regale, transmitting tissue, placenta, secretion, nuclear reticulum, transfer cells  相似文献   
990.
Abstract The utilization of urea was studied in the cyanobacterium Anabaena doliolum . The uptake of urea was unaltered in the presence of ammonium. The cells receiving ATP exogenously showed an induced level of urea-uptake as compared with the control cells. Urease inhibitor acetohydroxamic acid and hydroxyurea as well as glutamate analogue, MSO, did not affect the uptake of urea. These results suggest: (1) urea and ammonia have different uptake sites, (2) urea-uptake is an energy dependent process, and (3) during short-term experiments, urea uptake is not linked with the enzyme urease or the ammonium assimilating enzyme glutamine synthetase.  相似文献   
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