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41.
The tetrapeptide Acetyl-N-Ser-Asp-Lys-Pro (AcSDKP, Seraspenide; Ipsen- Biotech, Paris, France), an inhibitor of murine spleen colony-forming units reduces the number and the percentage in DNA synthesis of progenitors from human unfractionated bone marrow. To determine whether AcSDKP may directly affect the growth potential of purified progenitors even at the most primitive level, CD34+HLA-DRhigh and CD34++HLA-DRlow cells were highly purified by cell sorting. Then, CD34+ subsets were stimulated in liquid culture with combinations of growth factors (GFs) and AcSDKP was added for 20 hours or 6 days and cells plated in methylcellulose. After a 20-hour incubation, we show that AcSDKP (at 10(-10) mol/L) significantly inhibits the colony formation of both CD34+ subsets. Moreover, when added daily for 6 days, AcSDKP: (1) reduces the proliferation of both CD34+ cell fractions stimulated by 3 or 7 GFs, and (2) decreases the number of progenitors generated from the CD34+HLA-DRhigh and CD34++HLA-DRlow cell fractions. Furthermore, we show for the first time, using both high proliferative potential cell and long-term culture initiating cell assays, that AcSDKP inhibits the most primitive cells contained in the CD34++HLA-DRlow subpopulation. Finally, by using limiting dilution assays we demonstrated that AcSDKP acts directly at a single cell level and that its inhibitory effect is reversible and dose dependent.  相似文献   
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BACKGROUND AND AIMS: The evidence that proton pump inhibitor (PPI) therapy affects symptoms of nonulcer dyspepsia is conflicting. We conducted a systematic review to evaluate whether PPI therapy had any effect in nonulcer dyspepsia and constructed a health economic model to assess the cost-effectiveness of this approach. METHODS: Electronic searches were performed using the Cochrane Controlled Trials Register, MEDLINE, EMBASE, CINAHL, and SIGLE until September 2002. Dyspepsia outcomes were dichotomized into cured/improved versus same/worse. Results were incorporated into a Markov model comparing health service costs and benefits of PPI with antacid therapy over 1 year. RESULTS: Eight trials were identified that compared PPI therapy with placebo in 3293 patients. The relative risk of remaining dyspeptic with PPI therapy versus placebo was .86 (95% confidence interval, .78-.95; P = .003, random-effects model) with a number needed to treat of 9 (95% confidence interval, 5-25). There was statistically significant heterogeneity between trials (heterogeneity chi(2) = 30.05; df = 7; P < .001). The PPI strategy would cost an extra US dollar 278/month free from dyspepsia if the drug cost US dollar 90/month. If a generic price of US dollar 19.99 is used, then a PPI strategy costs an extra US dollar 57/month free from dyspepsia. A third-party payer would be 95% certain that PPI therapy would be cost-effective, provided they were willing to pay US dollar 94/month free from dyspepsia. CONCLUSIONS: PPI therapy may be a cost-effective therapy in nonulcer dyspepsia, provided generic prices are used.  相似文献   
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Patient-centred care (PCC) has emerged as a primary approach to health care. This approach emphasises partnerships in health between patients and healthcare professionals, acknowledges patients’ preferences and values, promotes flexibility in the provision of health care and seeks to move beyond the traditional paternalistic approach to health care. Thus, in addition to the physical aspects of health care, the PCC approach acknowledges a patient's beliefs and values towards wellbeing. One advantage of the PCC approach is its focus on enhanced patient satisfaction; however, recently, concerns have been raised as to the effects of the PCC on the evidence-based care approach, as the two approaches are viewed as mutually exclusive rather than complementary. The paper discusses the concept of PCC and considers its benefits both in relation to patients and health care organisations. It also considers the contribution of nurses to PCC and in the enhancement of service delivery.  相似文献   
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Information related to the clinical characteristics and isolated microbes associated with lung abscesses comparing immunocompromised (IC) to non-immunocompromised (non-IC) patients is limited. A retrospective review for 1984-1996 identified 34 consecutive adult cases of lung abscess (representing 0.2% of all cases of pneumonia), including 10 non-IC and 24 IC patients. Comparison of age, gender, tobacco use, pre-existing pulmonary disease or recognized aspiration risk factors were not significantly different between the two groups. Upper lobe involvement accounted for the majority of cases, although multi-lobe involvement was limited to IC patients. There were no differences in the need for surgical intervention, and mortality was very low for both groups. Anaerobes were the most frequent isolates for non-IC patients (30%), whereas aerobes were the most frequent isolate for IC patients (63%). Importantly, certain organisms were exclusively isolated in the IC group and multiple isolates were obtained only from the IC patients.Thus, comparing non-IC to IC patients, clinical characteristics may be similar whereas important differences may exist in the microbiology associated with lung abscess. These findings have important implications for the clinical management of these patient groups, and support a strategy to aggressively identify microbial agents in abscess material.  相似文献   
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The Latarjet procedure is an operation performed either arthroscopically or open for recurrent anterior shoulder instability, in the setting of glenoid bone loss; with good to excellent functional results. Despite excellent clinical results, the complication rates are reported between 15 and 30 %. Intraoperative complications such as graft malpositioning, neurovascular injury, and graft fracture can all be mitigated with meticulous surgical technique and understanding of the local anatomy. Nonunion and screw breakage are intermediate-term complications that occur in less than 5 % of patients. The long-term complications such as graft osteolysis are still an unsolved problem, and future research is required to understand the etiology and best treatment option. Recurrent instability after the Latarjet procedure can be managed with iliac crest bone graft reconstruction of the anterior glenoid. Shoulder arthritis is another complication reported after the Latarjet procedure, which poses additional challenges to both the surgeon and patient.  相似文献   
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