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Fatigue is a major complaint among advanced cancer patients. Several instruments are available for measuring fatigue. The EORTC QLQ-C30 is one of the most frequently used health-related quality of life (HRQOL) instruments, and it includes a three-item fatigue subscale. Limited knowledge exists about the validity, performance and sensitivity of EORTC QLQ-C30 fatigue scale as compared with a fatigue-specific instrument. The aim of the present study was to validate the EORTC QLQ-C30 fatigue scale (FA) against the Fatigue Questionnaire (FQ). The FQ is frequently used and was developed to measure fatigue in both cancer and noncancer populations. The FQ measures physical (PF, seven items) and mental fatigue (MF, four items). The study population included two different cohorts: A) patients with advanced metastatic cancer included in a prospective randomized study of palliative radiotherapy (n = 238); B) patients with leukaemia and malignant lymphoma curatively treated with stem-cell transplantation and high-dose chemotherapy (n = 128). The analysis demonstrated that the FA correlated higher with the PF scale (r = 0.67-0.75) as compared with the MF scale (r = 0.49-0.61). The item scale correlations between FA items and the PF scale were consistently higher than between FA items and the MF scale. A factor analysis including all the items within the FA and the FQ identified two factors. All FA items loaded on a PF factor (0.70-0.85). A floor/ ceiling effect, indicating a high number of respondents with lowest, respectively, highest scores was observed more frequently in the FA as compared with the FQ. The PF discriminated better between diagnostic groups with different levels of fatigue than the FA did. In conclusion, the EORTC QLQ-C30 fatigue scale is measuring physical fatigue. A floor/ ceiling effect seems to appear for the EORTC QLQ-C30 fatigue scale. The validity of the EORTC QLQ-C30 fatigue scale is to be questioned for use in palliative care patients. In studies with fatigue as a defined end point, a domain-specific instrument should, therefore, be added.  相似文献   
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Resnik L  Jensen GM 《Physical therapy》2003,83(12):1090-1106
BACKGROUND AND PURPOSE: Theoretical models of physical therapist expertise have been developed through research on physical therapists sampled solely on the basis of years of experience or reputation. Expert clinicians, selected on the basis of their patients' outcomes, have not been previously studied, nor have the patient outcomes of peer-nominated experts been analyzed. The purpose of our study was to describe characteristics of therapists who were classified as expert or average therapists based on the outcomes of their patients. SUBJECTS: Subjects were 6 therapists classified as expert and 6 therapists classified as average through retrospective analysis of an outcomes database. METHODS: The study was guided by grounded theory method, using a multiple case study design. Analysis integrated data from quantitative and qualitative sources and developed a grounded theory. RESULTS: All therapists expressed a commitment to professional growth and an ethic of caring. Therapists classified as expert were not distinguished by years of experience, but they differed in academic and work experience, utilization of colleagues, use of reflection, view of primary role, and pattern of delegation of care to support staff. Therapists classified as expert had a patient-centered approach to care, characterized by collaborative clinical reasoning and promotion of patient empowerment. DISCUSSION AND CONCLUSION: These findings add to the understanding of factors related to patient outcomes and build upon grounded theory for elucidating expert practice in physical therapy.  相似文献   
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Most human tumors overexpress or ectopically express peptide hormone/neurotransmitter receptors, which are being increasingly studied as a means to selectively deliver cytotoxic agents. Although a number of peptide ligand-constructs demonstrate tumor cytotoxicity, the role of specific tumoral receptor interaction in its mediation is unclear. To address this question, we synthesized camptothecin (CPT) bombesin (Bn) analogs, in which CPT was coupled via a novel carbamate linker, L2 [N-(N-methyl-amino-ethyl)-glycine carbamate], that were chemically similar but differed markedly in their potency/affinity for human Bn receptors. We then examined their ability to interact with Bn receptors and cause in vitro and in vivo tumor cytotoxicity. CPT-L2-[D-Tyr(6),beta-Ala(11),D-Phe(13),Nle(14)] Bn (6-14) (BA3) bound with high affinity and had high potency for all three human Bn receptor subtypes, whereas CPT-L2-[D-Tyr(6),beta-Ala(11), D-Phe(13),Nle(14)] Bn (6-14) [D-Phe-CPT-L2-BA3] had >1400-fold lower affinity/potency. (125)I-CPT-L2-BA3 but not (125)I-D-Phe-CPT-L2-BA3 was internalized by Bn receptor subtype-containing cells. CPT-L2-BA3 displayed significantly more cytotoxicity than D-Phe-CPT-L2-BA3 toward NCI-H1299 lung cancer cells in both 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide and clonogenic assays and more potently inhibited H1299 xenograft growth in nude mice. CPT-L2-BA3 was also metabolically more stable than its parent peptide and inhibited growth of a number of other tumor cell lines in vitro and in vivo. These results demonstrate that specific tumoral receptor interaction is important in mediating the ability of peptide ligand-cytotoxic constructs to cause cytotoxicity. Because many tumors overexpress Bn receptors, these results also demonstrate that CPT-L2-BA3 will be a useful agent for delivering receptor-mediated cytotoxicity to many different human tumors.  相似文献   
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An increased prevalence of liver diseases such as hepatitis C and nonalcoholic fatty liver results in an augmented incidence of the most common form of liver cancer, hepatocellular carcinoma (HCC). HCC is most often found in the cirrhotic liver and it can therefore be challenging to rely on anatomical information alone when diagnosing HCC. Valuable information on specific cellular metabolism can be obtained with high sensitivity thanks to an emerging magnetic resonance (MR) technique that uses 13C labeled hyperpolarized molecules. Our interest was to explore potential new high contrast metabolic markers of HCC using hyperpolarized 13C‐MR. This work led to the identification of a class of substrates, low molecular weight ethyl‐esters, which showed high specificity for carboxyl esterases and proved in many cases to possess good properties for signal enhancement. In particular, hyperpolarized [1,3‐13C2]ethyl acetoacetate (EAA) was shown to provide a metabolic fingerprint of HCC. Using this substrate a liver cancer implanted in rats was diagnosed as a consequence of an ~4 times higher metabolic substrate‐to‐product ratio than in the surrounding healthy tissue, (p = 0.009). Unregulated cellular uptake as well as cosubstrate independent enzymatic conversion of EAA, made this substrate highly useful as a hyperpolarized 13C‐MR marker. This could be appreciated by the signal‐to‐noise (SNR) obtained from EAA, which was comparable to the SNR reported in a literature liver cancer study with state‐of‐the‐art hyperpolarized substrate, [1‐13C]pyruvate. Also, the contrast‐to‐noise (CNR) in the EAA based metabolic ratio images was significantly improved compared with the CNR in equivalent images reported using [1‐13C]pyruvate.  相似文献   
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Podoplanin (PDPN) is a unique transmembrane receptor that promotes tumor cell motility. Indeed, PDPN may serve as a chemotherapeutic target for primary and metastatic cancer cells, particularly oral squamous cell carcinoma (OSCC) cells that cause most oral cancers. Here, we studied how a monoclonal antibody (NZ-1) and lectin (MASL) that target PDPN affect human OSCC cell motility and viability. Both reagents inhibited the migration of PDPN expressing OSCC cells at nanomolar concentrations before inhibiting cell viability at micromolar concentrations. In addition, both reagents induced mitochondrial membrane permeability transition to kill OSCC cells that express PDPN by caspase independent nonapoptotic necrosis. Furthermore, MASL displayed a surprisingly robust ability to target PDPN on OSCC cells within minutes of exposure, and significantly inhibited human OSCC dissemination in zebrafish embryos. Moreover, we report that human OSCC cells formed tumors that expressed PDPN in mice, and induced PDPN expression in infiltrating host murine cancer associated fibroblasts. Taken together, these data suggest that antibodies and lectins may be utilized to combat OSCC and other cancers that express PDPN.  相似文献   
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