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91.
The study was to determine the effect of preexisting pain on the perception of a painful stimulus. We conducted a cross-section study at an urban ED using convenience sampling. Adult patients who had a 20-g IV catheter placed as part of their ED care were eligible for the study. Patients were excluded for the following reasons: more than one IV attempt, altered mental status, visual impairment, intoxication, or a physical abnormality at the IV site. Patients were asked to indicate on a 10-cm visual analog scale (VAS) the amount of pain they had at baseline immediately before IV placement. They were then asked to indicate on a separate VAS the amount of pain caused by the IV placement. Correlation between baseline pain and pain of the IV was assessed using Pearson's rho. One hundred patients were enrolled in the study. The pain of IV placement did not differ significantly by gender, race, who placed the IV, or the location of the IV. The correlation between baseline pain and pain of the IV placement was poor (rho =.14, confidence interval:-.06-.33). The response to a standardized painful stimulus among ED patients does not correlate highly with the severity of preexisting pain.  相似文献   
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Acute kidney injury (AKI) is a common complication associated with high morbidity and mortality in hospitalized patients. One potential mechanism underlying renal injury is ischaemia/reperfusion injury (IRI), which attributed the organ damage to the inflammatory and oxidative stress responses induced by a period of renal ischaemia and subsequent reperfusion. Therapeutic strategies that aim at minimizing the effect of IRI on the kidneys may prevent AKI and improve clinical outcomes significantly. In this review, we examine the technique of remote ischaemic preconditioning (rIPC), which has been shown by several trials to confer organ protection by applying transient, brief episodes of ischaemia at a distant site before a larger ischaemic insult. We provide an overview of the current clinical evidence regarding the renoprotective effect of rIPC in the key clinical settings of cardiac or vascular surgery, contrast‐induced AKI, pre‐existing chronic kidney disease (CKD) and renal transplantation, and discuss key areas for future research.  相似文献   
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Cytogenetics represents the most valuable predictor for a poor outcome in patients with acute myeloid leukemia (AML), but it encompasses a heterogeneous patient population who might have diverse pathogenesis and clinical courses. In particular, the significance of complex chromosome aberrations within this cohort has seldom been addressed before. We analyzed 48 AML patients with adverse-risk cytogenetics in this study. The complex karyotype (three or more numerical/structural cytogenetic changes; 29 patients) was found to occur more frequently among the elderly than a noncomplex adverse karyotype (19 patients; median age, 71 vs. 48; P = 0.005). The patients' performance status was the sole independent factor determining the complete remission rate among patients receiving standard induction chemotherapy. On survival analysis, two factors independently predicted a longer overall survival: noncomplex karyotypes [vs. complex karyotypes, hazard ratio (HR) 0.434, 95% confidence interval (CI) 0.189-0.994, P = 0.048] and achievement of complete remission [(CR) vs. CR not reached, HR 0.170, 95% CI 0.051-0.572, P = 0.004)]. In conclusion, among AML patients with adverse cytogenetics, complex chromosomal aberrations occurred more frequently among the elderly and predicted a poor outcome. These patients should be considered as a unique entity and be separated from those with a noncomplex adverse cytogenetic change. Exploring the underlying mechanisms of leukemogenesis could improve the therapeutic outcome for this group of patients.  相似文献   
96.
The p53 tumor suppressor is mutated in most human tumors. MDM2, a well-known inhibitor of p53, is overexpressed in a large number of tumors, suggesting that increased levels of MDM2 also contribute to tumorigenesis. A novel p53 inhibitor, MDM4, was more recently identified. The role of MDM4 in cancer development is not well understood. We set out to examine the levels of MDM4 by immunohistochemistry in head and neck squamous carcinomas (HNSC) to ask whether high MDM4 levels could contribute to its development and progression. In addition, MDM2 and p53 levels were examined to identify overlapping expression patterns. MDM4 is present at high levels in 50% of HNSC. In addition, overexpression of MDM2 was detected in 80% of tumors, many of which were also positive for MDM4. A subset of tumors displayed high levels of all 3 proteins. Sequencing of the p53 gene revealed that tumors with positive immunoreactivity for MDM2 or MDM4, some of which also had high levels of p53, did not carry mutations in this gene. Thus, the detection of p53 by immunohistochemistry was not synonymous with the presence of p53 mutations. Expression of both MDM2 and MDM4 in tumors without p53 mutations strongly suggests that MDM2 and MDM4 inhibit the activity of this tumor suppressor in HNSC.  相似文献   
97.
Human lymphocytes derived from the blood of a donor immunized with anthrax vaccine were isolated and enriched for B-cells by Nycoprep density centrifugation. Individual anti-anthrax protective antigen (PA) B-cells were isolated by fluorescence activated cell sorting with fluorescence-labeled recombinant PA (rPA). The RNA from sorted single B-cells was extracted using plant total RNA as the carrier prior to purification by Nanoprep RNA isolation columns and then cDNA was prepared. Donor specific human Fab primer sets were developed based on rapid amplification of 5'-complementary DNA end results. Heavy chain and light chain of human Fab were amplified from the donor single B-cells by PCR. The amplified heavy and light chain were then cloned into the expression vector pASK-IBA2 and expressed in Escherichia coli (E. coli). The chains combined in vivo to form a functional Fab which was then purified as one protein. The human Fab antibodies produced by this technique were functional when tested in Western blots where the rPA was the target as well as in ELISA. This approach allowed us to obtain human Fab that retained the natural heavy and light chain pairing, which is supposed to have a high antigen-binding affinity.  相似文献   
98.

Background

Almost all studies of post-acute care (PAC) focus on older persons, frequently those suffering from chronic health problems. Some research is available on PAC for the pediatric population in general. However, very few studies focus on PAC services for children with special health care needs (SHCN).

Objective

To investigate factors affecting the provision of PAC to children with SHCN.

Methods

Pooled cross-sectional data from Texas Department of State Health Services hospital discharge database from 2011-2014 were analyzed. Publicly available algorithms identified chronic conditions, complex chronic conditions, and the principal problem leading to hospitalization. Analysis involved estimating two logistic regressions, with clustered robust standard errors, concerning the likelihood of receiving PAC and where that PAC was delivered. Models included patient characteristics and conditions, as well as hospital characteristics and location.

Results

Only 5.8 percent of discharges for children with SHCN resulted in the provision of PAC. Two-thirds of PAC was provided in a health care facility (HCF). Severity of illness and the number of complex chronic conditions, though not the number of chronic problems, made PAC more likely. Patient demographics had no effect on PAC decisions. Hospital type and location also affected PAC decision-making.

Conclusions

PAC was provided to relatively few children with SHCN, which raises questions concerning the potential underutilization of PAC for children with SHCN. Also, the provision of most PAC in a HCF (66%) seems at odds with professional judgment and family preferences indicating that health care for children with SHCN is best provided in the home.  相似文献   
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