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Rising demand for single-donor platelet components–from random donors, to maintain platelet inventories, or from HLA-compatible donors, to support alloimmune platelet-refractory patients–necessitated increasing the size of a community plateletpheresis donor registry. This study compares two strategies for recruiting whole-blood donors into a plateletpheresis program. The whole-blood donors who were asked to participate in this study had recently joined an unrelated bone marrow donor registry and had been HLA-typed as part of that process. An in-person recruitment strategy, which was time-intensive for the apheresis donor coordinator, served as the standard. A by-mail strategy involved the mailing of recruitment materials to marrow-donor registry participants. Marrow-donor registry participants were approached about apheresis participation after they had indicated an interest in the plateletpheresis program by returning a tear-off section of an informational brochure that was sent to them along with their marrow- donor registry materials. A total of 852 marrow-donor registry participants were randomly assigned to one of two recruitment strategies, and the recruitment rates were the same (46%) for both methods. In addition, levels of apheresis participation and attrition rates of donors recruited by either strategy were comparable. Thus, the simple strategy of mailing information about a plateletpheresis program is a very cost-effective method of recruiting donors. 相似文献
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Sodium taurolithocholate and sodium taurocholenate were infused intravenously into rats and hamsters. Each bile acid salt was given alone or in combination with varying amounts of a primary bile salt, either sodium taurocholate or sodium taurochenodeoxycholate. Bile flow, total bile acid salt excretion, and the excretion of sodium taurolithocholate were quantitatively determined. In addition, mannitol excretion in bile was determined at various flow rates.Sodium taurolithocholate was found to be rapidly excreted in bile in concentrations greater than its aqueous solubility. When the endogenous excretion rate of bile salt or the infusion of primary bile salt was less than the molar amount of administered sodium taurolithocholate, cholestasis always occurred. Increasing molar amounts of primary bile salt prevented cholestasis and enhanced the excretion rate of sodium taurolithocholate.Infusion of sodium taurocholenate, a nonhemolytic bile salt, caused an effect on bile flow and bile acid salt excretion qualitatively similar to sodium taurolithocholate.The induction of cholestasis can be attributed to the physical properties of these poorly water soluble bile salts. The reduction in bile flow could not be shown to be related to water reabsorption from the biliary tree since there was no increase in mannitol concentration in bile during cholestasis. Reduction in bile flow may be related to obstruction of segments of the biliary tree by precipitates of sodium taurolithocholate and possibly to a decrease in water entry into the biliary tree during infusion of this bile acid salt. 相似文献
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Hugh A. Gemmell DC EdDa Brad M. Hayes DCb 《Journal of manipulative and physiological therapeutics》2001,24(9):556-559
BACKGROUND: Satisfaction with care is one of the variables that can be used in determining the results of medical care. Patient satisfaction surveys allow managed care plans to determine how well their providers meet certain standards. OBJECTIVE: To determine the level of satisfaction with chiropractic care in a random sample of patients seen by physician members of a chiropractic independent physicians' association. DESIGN: A visit-specific questionnaire was mailed to a random sample of 150 patients from health insurance claims filed in the first two months of 2000. RESULTS: The rate of return was 44%. Various aspects of chiropractic care were given a rating of "excellent" by the following percentage of respondents: Length of time to get an appointment (84.9%); convenience of the office (57.7%); access to the office by telephone (77.3%); length of wait at the office (75.7%); time spent with the provider (74.3%); explanation of what was done during the visit (72.8%); technical skills of the chiropractor (83.3%); and the personal manner of the chiropractor (92.4%). The visit overall was rated as excellent by 83.3% of responders, and 95.5% stated they would definitely recommend the provider to others. CONCLUSION: The study demonstrated a high satisfaction rate among managed-care patients. 相似文献
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Changes in classic and alternative pathways of bile acid synthesis in chronic liver disease 总被引:1,自引:1,他引:1
Crosignani A Del Puppo M Longo M De Fabiani E Caruso D Zuin M Podda M Javitt NB Kienle MG 《Clinica chimica acta; international journal of clinical chemistry》2007,382(1-2):82-88
BACKGROUND: Cholesterol elimination occurs through bile acid synthesis that starts within the liver from 7alpha-hydroxylation or in extrahepatic tissues from 27-hydroxylation. This study was aimed at investigating in vivo these two pathways in patients with chronic liver disease. METHODS: Serum concentrations of 7alpha- and 27-hydroxycholesterol were measured in 54 patients (29 with primary biliary cirrhosis and 25 with chronic hepatitis C) and 18 controls. The rate of oxysterol plasma appearance was calculated after intravenous infusions of deuterated 7alpha- and 27-hydroxycholesterol in patients (n=8) and control subjects (n=8) who gave consent. The expression of sterol 27-hydroxylase was evaluated in macrophages isolated from 20 subjects. RESULTS: In patients with liver disease, the rate of plasma appearance of 7alpha-hydroxycholesterol was significantly reduced (1.44+/-0.96 vs. 2.75+/-1.43 mg/hour, p=0.03), the degree of reduction being related with the severity of the disease (p=0.01) whereas that of 27-hydroxycholesterol was unaffected. The rate of plasma appearance of 27-hydroxycholesterol was significantly related to its serum concentrations (r=0.54, p=0.03) and to its release from cultured macrophages ( r=0.85, p=0.03). CONCLUSIONS: In liver disease 7alpha-hydroxylation of cholesterol seems to be impaired while 27-hydroxylation is unaffected. Serum concentrations of 27-hydroxycholesterol are useful to obtain information on the activity of this alternative pathway. 相似文献
89.
Simon Dagenais DC PhD Darren M. Roffey PhD Eugene K. Wai MD MSc Scott Haldeman DC MD PhD Jaime Caro MD MSc 《The spine journal》2009,9(11):944-957
Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison. 相似文献
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