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101.
Consensus statement on the live organ donor   总被引:22,自引:0,他引:22  
The Authors for the Live Organ Donor Consensus Group

JAMA. 2000;284:2919-2926.

Objective  To recommend practice guidelines for transplant physicians, primary care providers, health care planners, and all those who are concerned about the well-being of the live organ donor.

Participants  An executive group representing the National Kidney Foundation, and the American Societies of Transplantation, Transplant Surgeons, and Nephrology formed a steering committee of 12 members to evaluate current practices of living donor transplantation of the kidney, pancreas, liver, intestine, and lung. The steering committee subsequently assembled more than 100 representatives of the transplant community (physicians, nurses, ethicists, psychologists, lawyers, scientists, social workers, transplant recipients, and living donors) at a national conference held June 1-2, 2000, in Kansas City, Mo.

Consensus Process  Attendees participated in 7 assigned work groups. Three were organ specific (lung, liver, and kidney) and 4 were focused on social and ethical concerns (informed consent, donor source, psychosocial issues, and live organ donor registry). Work groups' deliberations were structured by a series of questions developed by the steering committee. Each work group presented its deliberations to an open plenary session of all attendees. This information was stored and shaped into a statement circulated electronically to all attendees for their comments, and finally approved by the steering committee for publication. The term consensus is not meant to convey universal agreement of the participants. The statement identifies issues of controversy; however, the wording of the entire statement is a consensus by approval of all attendees.

Conclusion  The person who gives consent to be a live organ donor should be competent, willing to donate, free from coercion, medically and psychosocially suitable, fully informed of the risks and benefits as a donor, and fully informed of the risks, benefits, and alternative treatment available to the recipient. The benefits to both donor and recipient must outweigh the risks associated with the donation and transplantation of the living donor organ.

  相似文献   

102.
Background and Aims:  Work plays an important role in adults' well-being, irrespective of health status. Vocational rehabilitation can enable people with mental illness to return to open employment. A narrative approach was used to explore how individuals with a mental illness made sense of their work-related experiences.
Methods and Results:  Four Clubhouse members in open employment for at least 6 months completed in-depth, semistructured interviews, from which narratives were created to reveal events, significant persons and actions that assisted these individuals to resume work. Woven into the participants' stories were four 'impelling forces' contributing to a sense-of-self as a worker. These impelling forces were: support from significant others, the personal meaning of work, experiences within the Clubhouse programme, and the ongoing struggle with illness. Implications for occupational therapy practice are discussed.
Conclusion:  The findings of this study urge occupational therapists and others to provide opportunities to provide on-going support to people with a mental illness who seek paid employment.  相似文献   
103.
The short-term safety of mangafodipir trisodium (MnDPDP) injection was studied in 546 adults with known or suspected focal liver lesions. An initial contrast-enhanced computed tomography examination was followed by unenhanced magnetic resonance imaging (MRI), injection of MnDPDP (5 micromol/kg), and enhanced MRI. Adverse events were reported for 23% of the patients; most were mild to moderate in intensity, did not require treatment, and were not drug related. The most commonly reported adverse events were nausea (7%) and headache (4%). The incidence of serious adverse events was low (nine events in six patients) and not drug related. Injection-associated discomfort was reported for 69% of the patients, and the most commonly reported discomforts included heat (49%) and flushing (33%). Changes in laboratory values and vital signs were generally transient, were not clinically significant, and did not require treatment. There were no clinically significant short-term risks from exposure to MnDPDP.  相似文献   
104.
105.
BACKGROUND: The MLL 11q23 translocation arises in utero and is present in 75% of infant leukemias. That MLL+ acute myeloid leukemia (AML) can arise following chemotherapy with DNA topoisomerase II (DNAt2) inhibitors suggests that these substances, which also occur naturally in foods, may contribute toward infant leukemia. We hypothesized that maternal consumption of dietary DNAt2 inhibitors during pregnancy would increase the risk of infant leukemia, particularly AML(MLL+). METHODS: This Children's Oncology Group case-control study consisted of 240 incident cases of infant acute leukemia [AML and acute lymphoblastic leukemia (ALL)] diagnosed during 1996 to 2002 and 255 random digit dialed controls. Maternal diet during pregnancy was determined through a food frequency questionnaire. An index of specific foods identified a priori to contain DNAt2 inhibitors as well as vegetables and fruits were created and analyzed using unconditional logistic regression. RESULTS: There was little evidence of an association between the specific DNAt2 index and leukemia overall and by subtype. An exception was AML(MLL+); odds ratios (95% confidence intervals) comparing the second to fourth quartiles to the first were 1.9 (0.5-7.0), 2.1 (0.6-7.7), and 3.2 (0.9-11.9), respectively (P for trend = 0.10). For the vegetable and fruit index, there were significant or near-significant inverse linear trends for all leukemias combined, ALL(MLL+), and AML(MLL-). CONCLUSION: Overall, maternal consumption of fresh vegetables and fruits during pregnancy was associated with a decreased risk of infant leukemia, particularly MLL+. However, for AML(MLL+) cases, maternal consumption of specific DNAt2 inhibitors seemed to increase risk. Although based on small numbers, these data provide some support for distinct etiologic pathways in infant leukemia.  相似文献   
106.
PURPOSE: To investigate the gefitinib, fluorouracil (FU), leucovorin, and oxaliplatin regimen (IFOX) in previously treated patients with metastatic colorectal cancer. PATIENTS AND METHODS: Eligible patients had stage IV colorectal adenocarcinoma and had demonstrated progression or intolerance to a prior chemotherapy regimen not including oxaliplatin. Each cycle consisted of 14 days. Cycle 1 consisted of oxaliplatin 85 mg/m2 intravenously (IV) during 2 hours on day 1, hours 0 to 2; leucovorin 200 mg/m2 IV on days 1 and 2, hours 0 to 2; FU 400 mg/m2 IV push on days 1 and 2; and FU 600 mg/m2 IV on days 1 and 2, hours 2 to 24 (FOLFOX-4). All subsequent cycles consisted of FOLFOX-4 with gefitinib at 500 mg/d administered orally throughout the 14-day cycle. RESULTS: Twenty-seven patients were enrolled onto the study. The median number of prior chemotherapy regimens was two, and 74% of all patients received prior irinotecan. Nine of the 27 patients (33%) and six of the 20 patients (30%) who had prior FU and irinotecan had a partial response by Response Evaluation Criteria in Solid Tumors Group criteria. Median overall survival was 12.0 months. Median event-free survival was 5.4 months. Grade 3 to 4 toxicities included neutropenia (48%), diarrhea (48%), nausea (22%), and vomiting (15%). CONCLUSION: IFOX is an active regimen in patients with previously treated metastatic colorectal adenocarcinoma, demonstrating higher response rates than those reported with FOLFOX-4 alone in a similar patient population.  相似文献   
107.
PURPOSE: To ascertain parents' and physicians' assessments of quality of end-of-life care for children with cancer and to determine factors associated with high-quality care as perceived by parents and physicians. METHODS: A survey was conducted between 1997 and 2001 of 144 parents of children who received treatment at the Dana-Farber Cancer Institute and Children's Hospital (Boston, MA) or Children's Hospitals and Clinics of St Paul and Minneapolis, MN, between 1990 and 1999 (65% of those located and eligible) and 52 pediatric oncologists. RESULTS: In multivariable models, higher parent ratings of physician care were associated with physicians giving clear information about what to expect in the end-of-life period (odds ratio [OR] = 19.90, P = .02), communicating with care and sensitivity (OR = 7.67, P < .01), communicating directly with the child when appropriate (OR = 11.18, P < .01), and preparing the parent for circumstances surrounding the child's death (OR = 4.84, P = .03). Parent reports of the child's pain and suffering were not significant correlates of parental ratings of care (P = .93 and .35, respectively). Oncologists' ratings of care were inversely associated with the parent's report of the child's experience of pain (OR = 0.15, P = .01) and more than 10 hospital days in the last month of life (OR = 0.24, P < .01). Parent-rated communication factors were not correlates of oncologist-rated care. No association was found between parent and physician care ratings (P = .88). CONCLUSION: For parents of children who die of cancer, doctor-patient communication is the principal determinant of high-quality physician care. In contrast, physicians' care ratings depend on biomedical rather than relational aspects of care.  相似文献   
108.
BackgroundChildren with pharmacoresistant epilepsy usually receive ketogenic diet (KD) as an inpatient, which makes it an expensive treatment.ObjectiveTo compare the effectiveness, safety, and costs of outpatient versus inpatient initiated KD.DesignRetrospective observational non-inferiority study.Patients/settingPatients (1–18 years of age) who started KD either inpatient or outpatient.Main outcome measuresEffectiveness was defined as ≥50% seizure reduction. Safety was measured by the numbers of emergency visits and complications. Economic impact was analyzed by calculating total costs of treatment.Statistical analysesNon-inferiority of outpatient initiation was tested using 95% confidence intervals of the differences in effectiveness and safety endpoints between groups with non-inferiority margins of 10%. Nonparametric bootstrap techniques were used to derive a 95% confidence interval for the mean difference in total costs between the groups.ResultsHundred and five patients started KD in the period 2001 to 2017: 43 inpatient and 62 outpatient. At three months, the KD was effective in 61% of outpatients versus 63% of inpatients. The KD was considered safe in 36% of the outpatients, as compared to 29% in the inpatients. Outpatient initiation was shown to be non-inferior to inpatient initiation in terms of safety. Total health care costs of outpatient initiation were € 2901, as compared to € 8195 of inpatient initiation per patient (mean difference € 5294, 95% CI; -€ 7653 to -€ 2935).ConclusionsOur study suggests that outpatient KD initiation is no worse than inpatient initiation in terms of effectiveness and safety, while carrying lower health care costs.  相似文献   
109.
PURPOSE: Microsatellite instability (MSI) testing of colorectal cancer tumors is used as a screening tool to identify patients most likely to be mismatch repair (MMR) gene mutation carriers. We wanted to examine which microsatellite markers currently used to detect MSI best predict early-onset colorectal cancer caused by germ-line mutations in MMR genes. EXPERIMENTAL DESIGN: Invasive primary tumors from a population-based sample of 107 cases of colorectal cancer diagnosed before age 45 years and tested for germ-line mutations in MLH1, MSH2, MSH6, and PMS2 and MMR protein expression were screened for MSI using the National Cancer Institute panel and an expanded 10-microsatellite marker panel. RESULTS: The National Cancer Institute five-marker panel system scored 31 (29%) as (NCI)MSI-High, 13 (12%) as (NCI)MSI-Low, and 63 (59%) as (NCI)MS-Stable. The 10-marker panel classified 18 (17%) as (10)MSI-High, 17 (16%) as (10)MSI-Low, and 72 (67%) as (10)MS-Stable. Of the 26 cancers that lacked the expression of at least one MMR gene, 24 (92%) were positive for some level of MSI (using either microsatellite panel). The mononucleotide repeats Bat26, Bat40, and Myb were unstable in all (10)MSI-High cancers and all MLH1 and MSH2 mutation carriers (100% sensitive). Bat40 and Bat25 were unstable in all tumors of MSH6 mutation carriers (100% sensitive). Bat40 was unstable in all MMR gene mutation carriers (100% sensitive). By incorporating seven mononucleotide repeats markers into the 10-marker panel, we were able to distinguish the carriers of MSH6 mutations (all scored (10)MSI-Low) from the MLH1 and MSH2 mutation carriers (all scored (10)MSI-High). CONCLUSIONS: In early-onset colorectal cancer, a microsatellite panel containing a high proportion of mononuclear repeats can distinguish between tumors caused by MLH1 and MSH2 mutations from those caused by MSH6 mutations.  相似文献   
110.
Microbes are found in nearly every habitat and organism on the planet, where they are critical to host health, fitness, and metabolism. In most organisms, few microbes are inherited at birth; instead, acquiring microbiomes generally involves complicated interactions between the environment, hosts, and symbionts. Despite the criticality of microbiome acquisition, we know little about where hosts’ microbes reside when not in or on hosts of interest. Because microbes span a continuum ranging from generalists associating with multiple hosts and habitats to specialists with narrower host ranges, identifying potential sources of microbial diversity that can contribute to the microbiomes of unrelated hosts is a gap in our understanding of microbiome assembly. Microbial dispersal attenuates with distance, so identifying sources and sinks requires data from microbiomes that are contemporary and near enough for potential microbial transmission. Here, we characterize microbiomes across adjacent terrestrial and aquatic hosts and habitats throughout an entire watershed, showing that the most species-poor microbiomes are partial subsets of the most species-rich and that microbiomes of plants and animals are nested within those of their environments. Furthermore, we show that the host and habitat range of a microbe within a single ecosystem predicts its global distribution, a relationship with implications for global microbial assembly processes. Thus, the tendency for microbes to occupy multiple habitats and unrelated hosts enables persistent microbiomes, even when host populations are disjunct. Our whole-watershed census demonstrates how a nested distribution of microbes, following the trophic hierarchies of hosts, can shape microbial acquisition.

Microbial partners metabolize our food, fight off disease, and run the machinery that sustains the air we breathe, water we drink, and soil under our feet. Despite their importance, most host-associated microbes are generally not present at birth and are instead acquired (1). Because microbial symbionts can influence host health and fitness, the processes that determine how different microbiomes assemble within different hosts is a matter of active and urgent inquiry. Microbial ecologists have made great progress in determining how factors such as abiotic conditions (24), host evolution (5, 6), and microbial traits (79) shape environmental microbiomes, but considerably less is known about how surrounding environments or different guilds of host organisms contribute to host-associated microbiome composition. Longitudinal studies show that microbial richness accumulates and community composition changes over time across a wide diversity of hosts and habitats (1), but we know comparatively little about from where these microbes originate. To better understand microbial transmission and its role in community composition, we propose a framework that relies on theory from foodweb and landscape ecology.The concept of a foodweb has had a place in the ecological lexicon since at least the time of Elton (1927; (10)), and others such as Lindeman (11) and Odum (12) significantly expanded upon this notion to include how macroorganisms interact within their environments, in addition to their feeding relationships. The units of study for foodwebs are ecosystems, which are spatially explicit and include all organisms along with their abiotic environments and their interactions within its bounds (13). This definition was born from the efforts of the founders of the Hubbard Brook Ecosystem Study (HBES; 1963), who recognized that a watershed naturally delineates the boundaries of an ecosystem, an idea that parallels the Hawaiian ahupuaʻa concept. Since then, the HBES and its framework have led to numerous milestones in our understanding of processes such as the effects of long-term changes in acidification (14) and ecosystem impacts of global warming (15). Here, we adopt the notion of the watershed as an entire discrete ecosystem to better understand the landscape ecology of microbes. Landscape ecology is a means to understand how spatial processes affect biodiversity (16). In classic landscape ecology theory, the structure (heterogeneity) and fragmentation of habitats (or patches) within a matrix of otherwise inhospitable areas affect species’ dispersal ability and establishment. This ultimately shapes species’ abundance and distributions across the landscape (17). Contemporary landscape ecology theory extends this idea to include the concept of a landscape continuum, where continuous environmental variables, as opposed to discrete habitat patches surrounded by a matrix, better describe species’ distributions. Connecting these concepts, foodwebs are embedded in landscapes, and watersheds constitute a useful unit of measure to better understand their interactions.To expand concepts from foodweb and landscape ecology to be inclusive of microbes, we must first consider the following: a landscape for microbes can be both structural (e.g., different land covers or hydrology) and biotic (e.g., variation in the distribution of host populations). Also, microbes might better fit a continuous landscape model rather than a patch model if their distributions are not governed merely by the presence of a compatible host or habitat, but rather, if they exist among multiple hosts across a gradient of environmental conditions. This requires microbes to be generalists to some degree and/or a matrix that is at least partially hospitable (18). These considerations are important because while microbial transmission among related hosts is one obvious means of microbiome assembly, this model, in and of itself, is insufficient to sustain microbiomes (defined here as communities of bacteria and archaea) across a dynamic landscape. For example, many plants and animals are either sparse, seasonal, or ephemeral, requiring that their symbiotic microbes be capable of residing, at times, in alternate nearby hosts or environments. This potential for a microbe to persist in, and disperse among, hosts of different kingdoms and guilds, or even between liquid and land, is a trait with the potential to add an additional dimension to microbiome assembly theory (19). Where, then, might a host’s microbes reside when not inside that host? In addition, what factors might predict microbiome distributions among potentially interacting hosts and environments?Variability in matrix suitability and host specialization may result in differing microbial communities reflected in one of three nonmutually exclusive patterns, each of which leaves a diagnostic imprint on microbiome structure. If any host or environment has an equal likelihood of harboring microbes that are present in any other host or environment, we might expect host–microbe interaction networks that are randomly structured. Alternatively, if microbes are more likely to co-occur among related hosts or guilds, we might expect these to contain unique and specific consortia of microbes (modules) that are not found elsewhere in the interaction network. Finally, host–microbe interactions might be best characterized as stratified, resulting in a network topology in which microbial diversity is nested such that taxa-poor microbiomes are subsets of those that are taxa-rich. In this scenario, nonhost environmental matrices (e.g., soil, sediment, water) serve as reservoirs of broad microbial diversity that is subsequently, and hierarchically, partitioned into simpler microbiomes. While this concept is fairly intuitive, there are actually few, if any, studies that demonstrate transmission among environmental microbiomes and multiple hosts at ecosystem scales. Instead, many of the insights gleaned into assembly processes of microbiomes are owed to studies of single hosts, tractable model systems, or global syntheses (20). We address this gap by sampling microbiomes from aquatic, marine, and terrestrial foodwebs within a single watershed to examine the dynamics of sources and sinks of microbial diversity.Here, we present a microbial census of a model ecosystem metacommunity in which continental-scale environmental heterogeneity is recapitulated within a comparatively small watershed. Because of this, we can surmise the distribution limits of microbiomes across land, stream, and sea, a feat that would not be plausible in most other landscapes of similar size or environmental variability. From ridge to reef, our compact watershed spans a roughly 3.5 m rainfall differential, ∼27 times that encountered along the Mississippi, the largest watershed in continental North America. Also, our model ecosystem is located on the most isolated archipelago on the planet, making exogenous microbial inputs infrequent, if not unlikely. Furthermore, owing to parallels in environmental heterogeneity and foodweb structure across this compact watershed compared to others, our findings are potentially relevant for highly connected ecosystems that span substantially larger geographic areas.For example, a long-standing question in biogeography is the relationship between organisms’ local distributions and those at larger scales. Many factors influence the distributions of microbes, including their physiology, size, population density, and dispersal abilities (2123). A common assumption is that niche breadth should also predict the range size of an organism, since the ability to survive in broader environments, and to use a greater array of resources, should indicate the ability to occupy more habitats that occur over greater distances (24, 25). This is an important component of source and sink dynamics, because it suggests that local occupancy should predict global distributions. This relationship is seldom tested empirically, however, because small areas rarely contain, or are sampled for, broad climatic variability and host diversity. In the absence of phenotypic, genomic, or even well-resolved taxonomic information about the majority of the earth’s microbial biodiversity, geographic range is one of the few traits that can be directly inferred from short environmental DNA sequence reads. By examining our ecosystem-wide microbiome census within the context of the global survey of the Earth Microbiome Project (26), we assess the relationship between global and local microbial distributions.  相似文献   
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