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Patients who are diagnosed with localized prostate cancer need to make critical treatment decisions that are sensitive to their values and preferences. The role of decision aids in facilitating these decisions is unknown. The authors conducted a systematic review of randomized trials of decision aids for localized prostate cancer. Teams of 2 reviewers independently identified, selected, and abstracted data from 14 eligible trials (n = 3377 men), of which 10 were conducted in North America. Of these, 11 trials compared decision aids with usual care, and 3 trials compared decision aids with other decision aids. Two trials suggested a modest positive impact on decisional regret. Results across studies varied widely for decisional conflict (4 studies), satisfaction with decision (2 studies), and knowledge (2 studies). No impact on treatment choices was observed (6 studies). In conclusion, scant evidence at high risk of bias suggests the variable impact of existing decision aids on a limited set of decisional processes and outcomes. Because current decision aids provide information but do not directly facilitate shared decision making, subsequent efforts would benefit from user‐centered design of decision aids that promote shared decision making. CA Cancer J Clin 2015;65: 239–251. © 2015 American Cancer Society.  相似文献   
133.
Glycopeptide resistance may be either constitutive or transferable (on plasmids or as a transposon), and four phenotypes (van A, B, C, D) have been described to date. Recent data suggest solid media screening protocols appear to be insensitive at detecting low levels of carriage, and up to 40% of colonized patients may be falsely glycopeptide-resistant enterococci (GRE) negative. Managing GRE-colonized or -infected patients using contact precautions appears to be useful in controlling clonal outbreaks, but may be of limited utility once GRE is endemic. Alternate strategies to manage GRE-colonized patients with prolonged carriage and in outpatient or home health settings include using risk-based transmission assessment to limit the logistic and psychosocial difficulties associated with the use of continuous contact precautions. The therapeutic options for treating GRE infection remain limited. Attempts to decolonize GRE-colonized patients with bacitracin appear to be of limited utility.  相似文献   
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Hooberman  AL; Rubin  CM; Barton  KP; Westbrook  CA 《Blood》1989,74(3):1101-1107
The Philadelphia (Ph1) chromosome is an acquired abnormality in the malignant cells of 10% to 25% of patients with acute lymphoblastic leukemia (ALL). Unlike chronic myelogenous leukemia (CML), where the molecular detection of the Ph1 chromosome is relatively straightforward using conventional Southern hybridization analysis, the detection of the Ph1 chromosome in ALL is complicated by the existence of several molecular subtypes, and the fact that translocation breakpoints are dispersed over a large genomic area. To circumvent these difficulties, we investigated pulsed-field gel electrophoresis (PFGE) to determine if this method could be used directly on clinical samples to detect the Ph1 chromosome in ALL. We report that, in a study of seven patients with Ph1-positive ALL, we could easily detect the Ph1 using only a single PFGE analysis, regardless of the Ph1 subtype, and we could confirm that the translocations occur either within or very near the BCR gene in all seven. We conclude that PFGE is a useful technique for the detection of the Ph1 in ALL, which ultimately may find wide applicability in the detection of other chromosomal abnormalities in other malignancies.  相似文献   
136.
Expression of bcl-xL can confer a multidrug resistance phenotype   总被引:14,自引:3,他引:14  
Minn  AJ; Rudin  CM; Boise  LH; Thompson  CB 《Blood》1995,86(5):1903-1910
It has been suggested that genes that regulate apoptotic cell death may play an important role in determining the sensitivity of tumor cells to chemotherapy. We have recently cloned a member of the bcl-2 family, bcl- x. To test whether bcl-XL expression affects the sensitivity of tumor cells to chemotherapy, we have created stable cell lines overexpressing bcl-XL and have tested these cells for resistance to cell death induced by metabolic inhibitors and chemotherapeutic agents. Bcl-XL expression dramatically reduces the cytotoxicity of bleomycin, cisplatin, etoposide, vincristine, hygromycin B, and mycophenolic acid for up to 4 days in culture. Bcl-XL does not prevent cells from undergoing cell cycle arrest in response to these drugs, but rather prevents treated cells from undergoing apoptosis. Cell-cycle analysis on cells treated with the chemotherapeutic agents bleomycin, cisplatin, etoposide, and vincristine, show that the drugs cause growth arrest in different positions within the cell cycle. Bcl-XL expressing cells treated with chemotherapeutic drugs retain their proliferative ability after the drugs are removed. Interestingly, vincristine-treated cells expressing bcl-XL become polyploid after drug removal. These data show that bcl-XL protects cells from a wide variety of apoptotic stimuli, acts in multiple positions within the cell cycle, and confers a multidrug resistance phenotype. The ability of bcl-XL to prevent apoptotic cell death in response to chemotherapy-induced DNA damage and cell-cycle arrest may contribute to the accumulation of chromosomal aberrations within tumors. The expression of bcl-XL in tumor cells is likely to be an important indicator of chemotherapeutic efficacy.  相似文献   
137.
While there is evidence that omeprazole may induce changes in parietal cells, the effect of acid suppression on parietal cells in humans is poorly documented. This study was undertaken to evaluate the effects of omeprazole in human parietal cells over time. The light microscopic morphology of parietal cells in gastric biopsies from 17 patients on omeprazole were compared with those from 13 patients on ranitidine and 20 patients on no acid-lowering medication. Light microscopic and ultrastructural morphology of parietal cells was also evaluated in an additional 14 patients before and after omeprazole administration. Objective measurements of parietal cell height, mass and number were analyzed using analyses of variance. Electron microscopy was used to evaluate parietal cell enlargement. Twenty-five of 31 biopsies from patients on omeprazole, 1 of 13 from patients on ranitidine, and 0 of 20 from patients on neither drug showed parietal cell enlargement. Parietal cell height, mass, and number were increased in omeprazole-treated patients compared with ranitidine-treated patients and those on neither drug, and with the group also evaluated prior to beginning omeprazole treatment. Parietal cell height and mass were increased in patients on omeprazole longer than 12 months compared with biopsies from patients on the drug for less than 12 months. Resin-embedded sections and electron microscopy showed enlarged parietal cells with prominence of cytoplasmic tubulovesicles with sparse secretory canaliculi. Parietal cell hypertrophy and hyperplasia develops in patients on chronic omeprazole therapy; this can be recognized on routine examination of histologic sections. These morphologic changes increase with duration of therapy.  相似文献   
138.
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant.  相似文献   
139.
This study investigated the effect of alcohol consumption and smoking during pregnancy on the fatty acid composition of the infants. A total of 40 very-low-birth-weight (VLBW) infants, weighing between 750 and 1500 g, were enrolled in the study after being hospitalized and ventilated for respiratory distress syndrome (RDS). Maternal and infant demographic information was recorded. Questions regarding maternal smoking (none, < 10 and > or = 10 cigarettes/d) and alcohol consumption (none, occasionally, moderate and severe) were recorded. Erythrocyte membrane (EMB; n = 40) total fatty acid analyses were performed at birth (baseline) and on days 14 and 28 postnatally. During pregnancy, 42% of mothers consumed alcohol and 50% smoked. At birth, infants of mothers who smoked and consumed alcohol during pregnancy, had significantly higher blood docosahexaenoic acid (DHA; p < 0.05) than infants of mothers who abstained from both alcohol and smoking. The consequences of this finding remain unknown.  相似文献   
140.
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