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Terms used to label types of clinical recommendations and guidance are applied inconsistently and do not reflect the methods used to create each type. Here, the international Pediatric Oncology Supportive Care Guideline Network proposes a lexicon for types of recommendations and guidance documents. A lexicon describing three types of recommendations (clinical practice guideline–derived, good practice statement, and expert opinion statement) and two types of guidance documents (clinical practice guideline and expert opinion) is presented. Consistent use of this lexicon will allow pediatric oncology clinicians to readily appreciate the methods used to create clinical guidance.  相似文献   
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Granular cell tumors (GCTs) are rare soft tissue neoplasms which may be multicentric. The vast majority are benign, however approximately 100 malignant GCTs have been reported, with only 8 originating in the vulva. Malignant GCTs are very aggressive with very poor survival rates. As the diagnosis of malignant GCT carries an extremely poor prognosis, the utilization of EM ensures that the most accurate diagnosis possible can be rendered.  相似文献   
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HIV-specific CD8(+) T cells play a major role in the control of virus during HIV primary infection (PI) but do not completely prevent viral replication. We used IFN-gamma enzyme-linked immunospot assay and intracellular staining to characterize the ex vivo CD8(+) T-cell responses to a large variety of HIV epitopic peptides in 24 subjects with early HIV PI. We observed HIV-specific responses in 71% of subjects. Gag and Nef peptides were more frequently recognized than Env and Pol peptides. The number of peptides recognized was low (median 2, range 0-6). In contrast, a much broader response was observed in 30 asymptomatic subjects with chronic infection: all were responders with a median of 5 peptides recognized (range 1-13). The frequency of HIV-specific CD8(+) T cells among PBMC for a given peptide was of the same order of magnitude in both groups. The proportion of HIV-specific CD8(+)CD28(-) terminally differentiated T cells was much lower in PI than at the chronic stage of infection. The weakness of the immune response during HIV PI could partially account for the failure to control HIV. These findings have potential importance for defining immunotherapeutic strategies and establishing the goals for effective vaccination.  相似文献   
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Trypanosoma cruzi, the protozoan pathogen that causes Chagas' disease, can be found in the blood of infected individuals for their entire life span. This presents a serious challenge in safeguarding blood products. Transmission of T. cruzi from blood products is a frequent occurrence in Latin America, where Chagas' disease is endemic. This study was designed to determine whether T. cruzi could be inactivated in human platelet concentrates and plasma by a photochemical treatment process with long-wavelength UV A light (UVA, 320 to 400 nm) plus the psoralen amotosalen HCl (Cerus Corporation). Units of platelet concentrates (300 ml) and plasma (300 ml) were intentionally contaminated with approximately 10(6) T. cruzi trypomastigotes, the T. cruzi form found in the bloodstream, per ml. The viability of T. cruzi after photochemical inactivation was determined by their ability to replicate in 3T3 fibroblasts. Controls, including treatment with 150 micro M amotosalen or 3 J/cm(2) UVA alone, did not lead to reduction of the viability of T. cruzi in plasma or platelet concentrates. However, treatment with 150 micro M amotosalen plus 3 J/cm(2) UVA inactivated T. cruzi to undetectable levels in plasma and platelet concentrates. This represented a >5.4-log reduction of T. cruzi in platelet concentrates and >5.0-log reduction of T. cruzi in plasma. We conclude that the amotosalen plus UVA photochemical inactivation technology is effective in inactivating high levels of protozoan pathogens, such as T. cruzi, in platelet concentrates and plasma, as has been previously shown for numerous viruses and bacteria.  相似文献   
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OBJECTIVE: To test the hypothesis that a brief, formalized period of additional wheelchair skills training is safe and results in significantly greater improvements in wheelchair skills performance than a standard rehabilitation program. DESIGN: Randomized controlled trial. SETTING: Rehabilitation center. PARTICIPANTS: Thirty-five wheelchair users (20 with musculoskeletal disorders, 15 with neurologic disorders) admitted for initial rehabilitation. Subjects' mean age +/- standard deviation (SD) was 59+/-18.3 years. INTERVENTION: Subjects randomly allocated to the treatment group participated in the Wheelchair Skills Training Program (WSTP), averaging 4.5+/-1.5 training sessions, each 30 minutes long. Subjects in the control group did not receive any wheelchair skills training beyond that given in a typical rehabilitation stay. MAIN OUTCOME MEASURES: Wheelchair Skills Test (WST), version 2.4, before and after training. Changes in total percentage WST score and individual skill scores were examined. RESULTS: There were no adverse incidents. The control group's mean percentage score +/- SD increased from 60.1%+/-14.4% to 64.9%+/-13.3%, an 8% improvement of the posttest relative to the pretest (P=.01). The WSTP group's mean score increased from 64.9%+/-9.4% to 80.9%+/-5.6%, a 25% improvement of the posttest relative to the pretest (P<.000). The WSTP group showed significantly greater improvements than the control group (P<.000). Among the specific skills, significantly greater improvements were seen in the WSTP group for the gravel and high-curb descent skills (P<.001). CONCLUSIONS: The WSTP is safe and practical and has a clinically significant effect on the independent wheeled mobility of new wheelchair users. These findings have implications for the standards of care in rehabilitation programs.  相似文献   
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