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991.
RATIONALE AND OBJECTIVES: The purpose of this study was to determine the inpatient cost of routine (ie, without emergent conversion to open repair during the hospital stay) endovascular stent-graft placement in a consecutive series of patients undergoing elective endovascular repair of abdominal aortic aneurysm (AAA) at a single institution. MATERIALS AND METHODS: Inpatient hospital costs of 91 patients who underwent initial elective endovascular repair of AAA were analyzed retrospectively. All patients had participated in clinical trials at the authors' institution during the previous 6 years. Financial data were derived from the hospital's cost-accounting system; additional procedural data were collected from a departmental database and with chart review. Stent-graft and professional costs were excluded. RESULTS: The mean total cost for endovascular repair was $11,842 (standard deviation [SD], $5,127), mean procedure time was 149 minutes (SD, 79 minutes), and mean length of stay was 3.5 days (SD, 2.3 days). Total cost depended on stent-graft type (means, $12,428 [bifurcated] vs $9,622 [tube]; P = .0002) and strongly correlated with procedure time and length of hospital stay (r = 0.78 and 0.66, respectively; P < .0001). Ninety-six percent of total costs for all patients were attributable to the following departments: operating theater (31%), radiology (31%), nursing (22%), and anesthesia (12%). CONCLUSION: Overall costs are greater with bifurcated than with tube stent-grafts. Total procedure-related costs are divided relatively equally between the operating theater, the radiology department, and the combination of the nursing and anesthesia departments.  相似文献   
992.
Recent data demonstrate that dipyridamole-thallium (DTHAL) and sestamibi (DMIBI) are not predictive of adverse perioperative cardiac events in moderate-risk patients (one or more Eagle risk factors) undergoing major elective vascular surgery. Less data are available regarding the ability of DTHAL/DMIBI to predict adverse cardiac events on long term follow-up. We sought to determine whether an abnormal DTHAL/DMIBI is predictive of adverse cardiac events on long-term follow-up in moderate-risk patients undergoing major elective vascular surgery. Patients were enrolled prospectively between June 1997 and June 1999 at West Los Angeles VA and Harbor-UCLA Medical Centers. Adverse cardiac events were defined as congestive heart failure (CHF), myocardial infarction (MI), unstable angina (USA), and ventricular arrhythmias. Follow-up was obtained via clinic visits, telephone calls, and chart review. We studied 75 patients (76% male, 24% female) with a mean age of 65 years. Operative procedures were primarily femorodistal (83%) and aortic (16%). DTHAL/DMIBI results were normal in 35 patients (47%), demonstrated reversible ischemia in 26 (35%), and showed a fixed defect alone in 14 (18%). From the follow-up results of this study we conclude that there is no association between a reversible ischemia or an abnormal (fixed or reversible) DTHAL/DMIBI and adverse cardiac events or mortality on long-term follow-up in moderate-risk patients who have undergone major vascular surgery.  相似文献   
993.

Background

Whether screening mammography programs should include women in their 40s is controversial. In Canada, screening of women aged 40–49 years has not been shown to reduce mortality from breast cancer. Given that screening mammography reduces mean tumour size and that tumour size is inversely associated with survival, the lack of benefit seen with screening is puzzling and suggests a possible adverse effect on mortality of mammography or subsequent treatment (or both) that counterbalances the expected benefit derived from downstaging.

Methods

We followed 50,436 women 40–49 years of age until age 60 for mortality from breast cancer. Of those women, one half had been randomly assigned to annual mammography and one half to no mammography. The impact of mammography on breast cancer mortality was estimated using a left-censored Cox proportional hazards model.

Results

Of 256 deaths from breast cancer recorded in the study cohort, 134 occurred in women allocated to mammography, and 122 occurred in those receiving usual care and not allocated to mammography. The cumulative risk of death from breast cancer to age 60 was 0.53% for women assigned to mammography and 0.48% for women not so assigned. The hazard ratio for breast cancer–specific death associated with 1 or more screening mammograms before age 50 was 1.10 (95% confidence interval: 0.86 to 1.40).

Conclusions

Mammography in women 40–49 years of age is associated with a small but nonsignificant increase in the risk of dying of breast cancer before age 60. Caution should be exercised when recommending mammographic screening to women before age 50.  相似文献   
994.
Abstract

Microvesicles (MVs) released from leukocytes, platelets and endothelial cells are elevated in patients with acute coronary syndrome (ACS). In the present study, we assessed the potential pro-aggregatory properties of MVs obtained from ACS patients. Thus, we divided the patients into two groups based on clopidogrel-responsiveness, i.e. high on-treatment platelet reactivity (HPR; n?=?16), and low or normal on-treatment platelet reactivity (non-HPR; n?=?14), respectively. MVs from patients were obtained by high-speed centrifugation, and the pro-aggregatory effect of MVs added to fresh isolated platelets from healthy subjects were analyzed by 96-well microplate aggregometry. MVs from HPR patients significantly enhanced spontaneous platelet aggregation around two times more than MVs from non-HPR patients. The pro-aggregatory effect of three out of four MV phenotypes correlated to MV-concentrations as determined by flow cytometry. Furthermore, MVs from patients with diabetes mellitus (n?=?9) had a stronger pro-aggregatory effect compared to MVs from those without diabetes (n?=?21; p?=?.025 between groups). In conclusion, MVs from ACS patients with clopidogrel non-responsiveness enhance platelet aggregation, as do MVs from ACS patients with diabetes. Thus, MVs from patients with hyperreactive platelets boost platelet aggregation. Blocking MV-formation may reduce platelet hyperreactivity.  相似文献   
995.
While there are now extensive databases of human genomic sequences from both private and public efforts to catalog human nucleotide variation, there are very few large-scale surveys designed for the purpose of analyzing human population history. Demographic inference from patterns of SNP variation in current large public databases is complicated by ascertainment biases associated with SNP discovery and the ways that populations and regions of the genome are sampled. Here, we present results from a resequencing survey of 40 independent intergenic regions on the autosomes and X chromosome comprising ~210 kb from each of 90 humans from six geographically diverse populations (i.e., a total of ~18.9 Mb). Unlike other public DNA sequence databases, we include multiple indigenous populations that serve as important reservoirs of human genetic diversity, such as the San of Namibia, the Biaka of the Central African Republic, and Melanesians from Papua New Guinea. In fact, only 20% of the SNPs that we find are contained in the HapMap database. We identify several key differences in patterns of variability in our database compared with other large public databases, including higher levels of nucleotide diversity within populations, greater levels of differentiation between populations, and significant differences in the frequency spectrum. Because variants at loci included in this database are less likely to be subject to ascertainment biases or linked to sites under selection, these data will be more useful for accurately reconstructing past changes in size and structure of human populations.  相似文献   
996.
997.
End-of-life care is an essential part of undergraduate nursing education. However, students may not have the opportunity to be exposed to an actual end-of-life situation during clinical rotations. A pilot project was implemented to evaluate the use of forum theatre to teach end-of-life care to undergraduate nursing students. A simulation used live actors, with theatre faculty and students playing the roles of a hospice patient, family members, and nursing students providing end-of-life care. Additional nursing students were participant observers. Using forum theatre methods, students identified important moments that occurred during the simulation and suggested alternative actions for those moments. The simulation was repeated using those alternatives and was evaluated by the students. Group debriefing was provided by nursing faculty with all students. A reflective journal entry was completed by all students. Project outcomes indicated that forum theatre was an effective teaching method for the topic of end-of-life care.  相似文献   
998.
999.
Despite prophylaxis with immunosuppressive agents or a variety of other approaches, many patients suffer from acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation. Although consensus has emerged supporting the use of high-dose methylprednisolone or prednisone for initial treatment of aGVHD, practices differ among centers with respect to the initial glucocorticoid dose, the use of additional immunosuppressive agents, and the approach to withdrawal of treatment after initial improvement. Despite many studies, practices vary considerably with respect to the selection of agents for treatment of glucocorticoid-resistant or refractory GVHD. Investigators and clinicians have recognized the lack of progress and lamented the absence of an accepted standard of care for secondary treatment of aGVHD. The American Society of Blood and Marrow Transplantation has developed recommendations for treatment of aGVHD to be considered by care providers, based on a comprehensive and critical review of published reports. Because the literature provides little basis for a definitive guideline, this review also provides a framework for the interpretation of previous results and the design of future studies.  相似文献   
1000.
The role of the peripheral blood (PB) CD34(+) cell count in predicting the CD34(+) cell yield in hematopoietic progenitor cell apheresis collections is well established. However, sometimes unexpectedly poor CD34(+) cell yields are obtained. To determine the effect, if any, of a range of factors on the ability of the PB CD34(+) count to predict collection CD34(+) cell count, we performed a retrospective analysis on consecutive hematopoietic progenitor cell apheresis collections between 2004 and 2008. Factors investigated included mobilization regimen, PB white blood cell count, body weight, and disease. After exclusion of collections involving apheresis complications, a total of 1,225 PB CD34(+) cell results with corresponding collection CD34(+) cell results from 458 patients were analyzed. Although differences in the median PB CD34(+) cell counts and collection CD34(+) cell counts were seen between mobilized collections with chemotherapy plus granulocyte colony-stimulating factor and those with granulocyte colony-stimulating factor alone, the predictive capability of the PB CD34(+) cell count for the collection CD34(+) cell yield remained similar. Although poorer collection efficiencies were observed in the myelodysplastic syndrome/myeloproliferative disorder diagnostic subgroup, our findings confirm that PB CD34(+) cell analysis remains a powerful and irreplaceable tool for predicting hematopoietic progenitor cell apheresis CD34(+) cell yield.  相似文献   
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