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991.

Background

Primary angioplasty has been introduced for the treatment of symptomatic cerebral vasospasm in patients with subarachnoid hemorrhage (SAH). The data regarding the therapeutic benefit of angioplasty in improving patient outcomes are limited, hence its utilization at hospitals remains controversial and currently is not reimbursed by Medicare or major insurance companies.

Methods

We analyzed the data from Nationwide Inpatient Sample (NIS), a nationally representative dataset of all admissions in the United States from 2005 to 2007. We analyzed the prevalence of angioplasty procedure for cerebral vasospasm at the national level. In-hospital mortality, discharge status, length of stay, and cost of hospitalization were compared between hospitals performing angioplasty with those not performing angioplasty in multivariable model, adjusted for patient’s age, utilization of endovascular aneurysm obliteration, and disease severity.

Results

Of the 74,356 estimated patients with nontraumatic SAH, 47% (n = 35,172) were admitted to hospitals that perform angioplasty for cerebral vasospasm and only 1307 patients (3.8%) were treated with angioplasty for vasospasm. In multivariable analysis, after adjustment for patient and hospital characteristics, we found that patients admitted to hospitals performing angioplasty had higher rates of discharge to home without supervision (OR 1.3, 95% CI: 1.1–1.6). There was no difference in in-hospital mortality, length of stay, or cost of hospitalization.

Conclusions

Our analysis suggests that the odds of a patient being discharged to home are better at hospitals performing angioplasty for cerebral vasospasm. Provision of angioplasty may be used as a surrogate marker of model of care in management of patients with SAH.
  相似文献   
992.
993.
994.
A NaI(Tl)-based gamma spectrometer for the analysis of geological materials was calibrated using the IAEA reference materials RGU-1, RGTH-1 and RGK-1. To simulate typical geological samples, two additional standards were prepared from aliquots of the three reference materials. The reproducibility of the instrument calibration factors (CFs) was tested by repeated measurements of the pure IAEA reference materials and the mixed samples in a reproducible counting geometry. The results were analysed using a two-way classification analysis of variance; it was found that the variance in the CFs is significantly higher between standards than it is between measurements. Allowance should be made for this when estimating uncertainties in measurements with the NaI(Tl) spectrometers.  相似文献   
995.
Prostate cancer is the most frequently diagnosed cancer and the second leading cause of death in males in the United States. Using human prostate cancer specimens, the authors have previously shown that elevated expression levels of 12‐lipoxygenase (12‐LOX) occurred more frequently in advanced stage, high‐grade prostate cancer, suggesting that 12‐LOX expression is associated with carcinoma progression and invasion. Previous reports from their group and others have shown that 12‐LOX is a positive modulator of invasion and metastasis; however, the mechanism remains unclear. In this work, a new link between 12‐LOX and the matrix metalloproteinase 9 (MMP9) in prostate cancer angiogenesis is reported. This study demonstrated that overexpression of 12‐LOX in prostate cancer PC‐3 cells resulted in elevated expression of MMP9 mRNA, protein and secretion. Exogenous addition of 12(S)‐hydroxy eicosatetraenoic acid, the sole and stable end product of arachidonic acid metabolism by 12‐LOX, is able to increase MMP9 expression in wild‐type PC‐3 cells. Furthermore, using pharmacological and genetic inhibition approaches, it was found that 12‐LOX activates phosphoinositol 3 kinase (PI3K)/Akt, which results in nuclear factor‐kappa B (NF‐κB)‐driven MMP9 expression, ensuing in enhanced chemoattraction of endothelial cells. Specific inhibitors of 12‐LOX, PI3K or NF‐κB inhibited MMP9 expression in 12‐LOX‐expressing PC‐3 cells and resulted in the blockade of the migratory ability of endothelial cells. In summary, the authors have identified a new pathway by which overexpression of 12‐LOX in prostate cancer cells leads to augmented production of MMP9 via activation of PI3K/Akt/NF‐κB signaling. The role of 12‐LOX‐mediated MMP9 secretion in endothelial cell migration may account for the proangiogenic function of 12‐LOX in prostate cancer.  相似文献   
996.
997.
The Breast and Cervical Cancer Prevention and Treatment Act of 2000 (BCCPTA) allows states the option of extending Medicaid eligibility to women diagnosed with breast or cervical cancer through a large federal screening program that does not include resources for treatment. Using qualitative data from interviews with 22 key informants and other sources, we present an analysis of the history and passage of the BCCPTA as a policy response to a perceived "treatment gap" in a national screening program. The results suggest that organizational policy entrepreneurs-primarily the National Breast Cancer Coalition-constructed an effective problem definition (that the government screening program was "unethical" and "broken") with a viable policy solution (an optional disease-specific Medicaid expansion), and pushed this proposal through a policy window opened by a budget surplus and an election year in which women's health issues had broad bipartisan appeal.  相似文献   
998.

Introduction

Obese patients with acute dyspnea may be prone to misorientation from the emergency department (ED), due to impaired gas exchange evaluation and altered basal respiratory profiles. This study aims to evaluate the prognostic value of arterial blood pH in obese ED patients with acute dyspnea in comparison to non-obese counterparts.

Methods

Single-center observational study of a cohort of 400 consecutive ED patients with acute dyspnea. The primary endpoint was a composite of Intensive Care Unit admission (with critical care needs) or in ED mortality. Predictors of the primary endpoint were assessed using multivariable logistic regression and ROC curve analysis, in obese (BMI?≥?30?kg·m?2) and non-obese patients.

Results

252 patients who had arterial blood gas testing were analyzed including 76 (30%) obese comparable to non-obese in terms of clinical history. 51 patients were admitted to ICU and 2 deceased before admission (20 obese (26%) vs 33 non-obese (19%); p?=?0.17). Factors associated with ICU admission were arterial blood pH (pH?<?7.36 vs pH?≥?7.36) and gender. In multivariate models adjusted for risk factors, pH remained the sole independent predictor in obese patients, with no predictive value in non-obese patients (ROC AUC: 0.74, 95% CI [0.60; 0.87], optimal threshold for pH: 7.36, odds ratio: 10.5 [95% CI 3.18; 34.68]).

Conclusion

Arterial blood pH may selectively predict critical care needs in ED obese patients with acute dyspnea, in comparison to non-obese. A falsely reassuring pH?<?7.36 should be regarded as a marker of severity when assessing acute dyspnea in obese ED patients.  相似文献   
999.
To investigate the pregnancy outcome of the fetuses with trisomy 18, we studied 123 cases of trisomy 18 who were born at our hospital from 1993 to 2009. Among them, 95.9% were diagnosed with trisomy 18 prenatally. Prenatal ultrasound findings showed fetal growth restriction in 77.2%, polyhydramnios in 63.4% and congenital heart defects in 95.1%. For 18 cases, cesarean section (C‐section) was chosen, and for 75 cases, transvaginal delivery was chosen. Premature delivery occurred in 35.5%. Stillbirths occurred in 50 cases (40.7%). Fetal demise before onset of labor occurred in 30 cases and fetal demise during labor occurred in 20 cases which was 26.7% of vaginal deliveries. Among the 73 live‐born infants, the survival rate for 24 h, 1 week, 1 month and 1 year were 63%, 43%, 33% and 3%. The median survival time was 3.5 days. There was no significant difference between the survival time of C‐section and that of vaginal delivery. However, for the births involving breech presentation, the survival time of C‐section was significantly longer than that of vaginal delivery. When the fetus is diagnosed with trisomy 18, the parents have to make many choices. These findings constitute critical information in prenatal counseling to the couples whose fetuses have been found to have trisomy 18, especially when they choose palliative approaches in the perinatal management.  相似文献   
1000.
A new method of chemoembolization with degradable starch microspheres (DSM) was used for patients with malignant hepatic tumors. DSM, 40-45 micron in diameter, which are degraded by serum amylase, temporarily obstruct arterial blood flow at the arteriolar capillary bed. Experimental studies have demonstrated that such occlusion enhances the regional uptake and reduces systemic exposure to simultaneously administered arterial anticancer drugs. Transcatheter chemoembolization with DSM was performed in 14 cases of hepatocellular carcinoma and 8 cases of metastatic liver cancer. Adriamycin or Mitomycin C mixed with DSM was injected into the patients with hepatocellular carcinoma or metastatic liver cancer, respectively, through the proper hepatic artery. The therapeutic effect of this chemoembolization was evaluated by the change in tumor size measured by angiography or computed tomography. In hepatocellular carcinoma, tumor regression of over 50% was observed in 5 of 14 patients. Elevated serum AFP level of more than 200 ng/ml was decreased in all 6 cases. In metastatic liver cancer, tumor regression of over 50% was observed in 4 of 8 cases. Although half of the patients had transient pain within 2 hours, no major side effects such as bone marrow suppression and hepatotoxicity were observed. Our results suggest that chemoembolization with DSM can be effectively used in the treatment of malignant hepatic tumors.  相似文献   
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