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221.
Investigation of the wood bark of Guarea guidonia (Meliaceae) led to the isolation of a limonoid (mombasol), a coumarin (scopoletin), and six sesquiterpenes [trans-1(10)-epoxy-4(15)-caryophyllene, 1(10)-epoxy-4,7-humuladiene, viridiflorol, 1(10),4-diepoxy-7-humulene, 3-oxo-10-alloaromadendranol, 1beta-6alpha-dihydroxyeudesm-4(15)ene]. The occurrence of these metabolites in the Guarea genus is reported for the first time. Stigmasterol, sitosterol and its oleate and palmitate esters were also obtained. Some corrections to the previously reported chemical shift assignments of 3-oxo-10-alloaromadendranol ( (13)C-NMR) were made.  相似文献   
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Between August 1989 and November 2003, 33 patients at our center with acquired aplastic anemia underwent bone marrow transplantation (BMT) from HLA-identical sibling donors with cyclophosphamide and in vivo anti-CD52 monoclonal antibodies (MoAb) for conditioning. The median age at BMT was 17 years (range, 4-46 years). Before BMT, 58% were heavily transfused (>50 transfusions), and 42% had previously experienced treatment failure with antithymocyte globulin-based immunosuppressive therapy. Unmanipulated bone marrow was used as the source of stem cells in all patients except 1. Graft-versus-host disease (GVHD) prophylaxis was with cyclosporine alone in 19 (58%) patients; 14 received anti-CD52 MoAb in addition to cyclosporine. The conditioning regimen was well tolerated without significant acute toxicity. Graft failure was seen in 8 patients (primary, n = 4; secondary, n = 4). Of those whose grafts failed, 4 survived long-term (complete autologous recovery, n = 2; rescue with previously stored marrow, n = 1; second allograft, n = 1). The cumulative incidence of graft failure and grade II to IV acute and chronic GVHD was 24%, 14%, and 4%, respectively. None developed extensive chronic GVHD. With a median follow-up of 59 months, the 5-year survival was 81% (95% confidence interval, 68%-96%). No unexpected early or late infectious or noninfectious complications were observed. We conclude that the conditioning regimen containing cyclophosphamide and anti-CD52 MoAb is well tolerated and effective for acquired aplastic anemia with HLA-matched sibling donors. The favorable effect on the incidence and severity of GVHD is noteworthy in this study and warrants further investigation.  相似文献   
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PURPOSE: Response of solid malignancies to therapy is usually determined by serial measurements of tumor size. The purpose of our study was to assess the consistency of measurements performed by readers evaluating lung tumors. MATERIALS AND METHODS: The study group was composed of 33 patients with lung tumors more than 1.5 cm. Bidimensional (BD) and unidimensional (UD) measurements were performed on computed tomography (CT) scans according to the World Health Organization (WHO) criteria and the Response Evaluation Criteria in Solid Tumors (RECIST), respectively. Measurements were performed independently by five thoracic radiologists using printed film and were repeated after 5 to 7 days. Inter- and intraobserver measurement variations were estimated through statistical modeling. RESULTS: There were 40 tumors with an average size of 1.8 to 8.0 cm (mean, 4.1 cm). Analysis of variance showed a significant difference (P <.05) among readers and among the measured nodules for UD and BD measurements. Interobserver misclassification rates were more than intraobserver misclassification rates using either progressive disease or response criteria. The probability of misclassifying a tumor with the WHO criteria or RECIST was greatest with interobserver measurements when criteria for progression (43% BD, 30% UD) were used and lowest with intraobserver measurements when criteria for response (2.5% BD, 3.0% UD) were used. In addition, interobserver misclassification rates were more than intraobserver misclassification rates for both regular and irregular tumors. CONCLUSION: Measurements of lung tumor size on CT scans are often inconsistent and can lead to an incorrect interpretation of tumor response. Consistency can be improved if the same reader performs serial measurements for any one patient.  相似文献   
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Lagarde M  Haines A  Palmer N 《JAMA》2007,298(16):1900-1910
Context  Cash transfers conditional on certain behaviors, intended to provide access to social services, have been introduced in several developing countries. The effectiveness of these strategies in different contexts has not previously been the subject of a systematic review. Objective  To assess the effectiveness of conditional monetary transfers in improving access to and use of health services, as well as improving health outcomes, in low- and middle-income countries. Data Sources  Relevant publications were identified via electronic medical and social science databases from inception to April 2006 (PubMED, EMBASE, POPLINE, CAB Direct, Healthcare Management Information Consortium, WHOLIS (World Health Organization Library Database), African Healthline, International Bibliography of the Social Sciences (IBSS), Eldis, British Library for Development Studies (BLDS), ID21, Journal Storage (Jstor), Inter-Science, ScienceDirect, Internet Documents in Economics Access Service (Research Papers in Economics) (IDEAS[Repec]), Latin American and Caribbean Health Sciences Literature (LILACS), MEDCARIB, Virtual Library in Health (ADOLEC), Pan American Health Organization (PAHO), FRANCIS, The Cochrane Central Register of Controlled Trials, the Database of Abstracts of Reviews of Effectiveness, and the Effective Practice and Organization of Care Group (EPOC) Register. Reference lists of relevant papers and "gray" literature resources were also searched. Study Selection  To be included, a paper had to meet study design criteria (randomized controlled trial, interrupted time series analysis, and controlled before and after study) and include a measure of at least 1 of the following outcomes: health care utilization, health expenditure, or health outcomes. Twenty-eight papers were retrieved for assessment and 10 were included in this review. Data Extraction  Methodological details and outcomes were extracted by 2 reviewers who independently assessed the quality of the papers. Results  Overall, the evidence suggests that conditional cash transfer programs are effective in increasing the use of preventive services and sometimes improving health status. Conclusions  Further research is needed to clarify the cost effectiveness of conditional cash transfer programs and better understand which components play a critical role. The potential success and desirability of such programs in low-income settings, with more limited health system capacity, also deserves more investigation.   相似文献   
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The diagnosis, staging, and response assessment of mesothelioma pose unique challenges to radiologic imaging. No single, conventional imaging approach captures the information necessary to direct all aspects of patient management. Instead, the complexities of this unique disease demand the integration of elements cleverly adapted from different modalities. Imaging-based studies presented at the 8th International Conference of the International Mesothelioma Interest Group (IMIG) in October 2006 sought to further define the current practice and future potential of radiology for the mesothelioma patient. The imaging studies selected through a peer-review process for presentation at the 2006 IMIG Conference were intended to frame this research in the context of the unique imaging challenges presented by mesothelioma while stimulating dialogue on the future resolution of these challenges. This communication conveys the pitfalls and potential of pleural mesothelioma imaging based on work presented at the Conference. From diagnosis to response, PET/CT to molecular bioprobes, volumetric analysis to computerized tumor assessment, imaging promises to provide valuable insight for patients with mesothelioma and the physicians who treat them.  相似文献   
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In the past decades, the regulation of pro-inflammatory cytokine production, including interleukin-8 (IL-8), has been the goal of many targeted therapeutic interventions for Necrotising enterocolitis (NEC), a gastrointestinal disease commonly associated with a very low birth weight in preterm infants. In this study, the ability to regulate the production of IL-8 of the water-soluble non-starch polysaccharide (WS-NSP) from taro corm (Tc-WS-NSP) extracted using a conventional (CE) or improved conventional (ICE) extraction method, of the probiotics Lactobacillus acidophilus, Bifidobacterium breve, and Bifidobacterium infantis, and their synbiotic mixtures were evaluated. The TNF-α stimulated HT-29 cells were incubated with undigested or digested Tc-WS-NSPs (CE or ICE), probiotics, and their synbiotic mixtures with Klebsiella oxytoca, an NEC-positive-associated pathogen. Overall, the synbiotic mixtures of digested Tc-WS-NSP-ICE and high bacterial concentrations of L. acidophilus (5.57 × 109), B. breve (2.7 × 108 CFU/mL), and B. infantis (1.53 × 108) demonstrated higher (42.0%, 45.0%, 43.1%, respectively) ability to downregulate IL-8 compared to the sole use of Tc-WS-NSPs (24.5%), or the probiotics L. acidophilus (32.3%), B. breve (37.8%), or B. infantis (33.1%). The ability demonstrated by the Tc-WS-NSPs, the probiotics, and their synbiotics mixtures to downregulate IL-8 production in the presence of an NEC-positive-associated pathogen may be useful in the development of novel prophylactic agents against NEC.  相似文献   
230.
Baharestani MM  Ratliff CR 《Advances in skin & wound care》2007,20(4):208, 210, 212, 214, 216, 218-208, 210, 212, 214, 216, 220
Acutely ill and immobilized neonates and children are at risk for pressure ulcers, but a paucity of evidence-based research exists on which to base guidelines for clinical practice. Most prevention and treatment protocols for pressure ulcers in the pediatric population are extrapolated from adult practice. Clinical practice guidelines for prevention and treatment of pressure ulcers that specifically address the needs of the pediatric population are needed. The purpose of this article is to highlight the research that is currently available and to identify gaps that need to be addressed so that science-based, age-appropriate prevention and treatment pressure ulcer guidelines can be developed.  相似文献   
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