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BACKGROUND AND METHOD: The role of thrombus formation in the pathogenesis of acute myocardial infarction (AMI) and unstable angina pectoris has been well established. However, comprehensive and systematic studies of the blood coagulation, fibrinolytic, and inhibitory proteins are not available in patients with these conditions. Fourteen patients with AMI, 10 patients with angina pectoris, and 32 normal volunteers were studied. Plasma antigen concentrations and/or activities of high-molecular-weight kininogen (HMWK), fibrinogen, fibronectin, plasminogen, D-dimer, tissue plasminogen activator (t-PA), alpha 2-antiplasmin, alpha 2-macroglobulin, alpha 1-antitrypsin, protein C, total and free protein S, antithrombin III (AT-III), von Willebrand factor (vWF), factors (F) XII, XI, IX, VIII, VII, X, V, II, and XIII, and plasma antiplasmin activity were measured using appropriate functional or immunologic assays. RESULTS: The AMI group showed a significant reduction in F XII activity, F XII activity-to-concentration ratio, and HMWK concentration. In addition, the AMI patients exhibited a significant elevation of plasma F XI activity, F IX concentration, and F IX activity, and vWF, fibrinogen, D-dimer, and t-PA concentrations. This was associated with significant reductions in F V, F II, and AT-III activity-to-concentration ratio. Many of the changes observed in AMI patients were also present in patients with angina pectoris. Furthermore, the latter group exhibited an elevation of F VIII activity, alpha 2-macroglobulin activity, and alpha 1-antitrypsin concentration and a significant reduction of antiplasmin activity despite a normal alpha 2-antiplasmin concentration. CONCLUSIONS: The observed reduction of the plasma F XII activity-to-antigen concentration ratio combined with a reduced HMWK concentration suggests intrinsic pathway activation, while the elevation of the D-dimer concentration indicates thrombin generation and fibrin formation and degradation in the AMI group. The latter changes were also present in patients with angina pectoris. Both AMI and angina groups showed several other abnormalities of the coagulation, fibrinolytic, and inhibitory systems. The results suggest the presence of a prothrombotic state associated with the activation of coagulation and fibrinolytic systems in patients with acute myocardial ischemia or infarction.  相似文献   
675.
Residents of long‐term care facilities have highly complex care needs and quality of care is of international concern. Maintaining resident wellness through proactive assessment and early intervention is key to decreasing the need for acute hospitalization. The Residential Aged Care Integration Program (RACIP) is a quality improvement intervention to support residential aged care staff and includes on‐site support, education, clinical coaching, and care coordination provided by gerontology nurse specialists (GNSs) employed by a large district health board. The effect of the outreach program was evaluated through a randomized comparison of hospitalization 1 year before and after program implementation. The sample included 29 intervention facilities (1,425 residents) and 25 comparison facilities (1,128 residents) receiving usual care. Acute hospitalization rate unexpectedly increased for both groups after program implementation, although the rate of increase was significantly less for the intervention facilities. The hospitalization rate after the intervention increased 59% for the comparison group and 16% for the intervention group (rate ratio (RR) = 0.73, 95% confidence interval (CI) = 0.61–0.86, P < .001). Subgroup analysis showed a significantly lower rate change for those admitted for medical reasons for the intervention group (13% increase) than the comparison group (69% increase) (RR = 0.67, 95% CI = 0.56–0.82, P < .001). Conversely, there was no significant difference in the RR for surgical admissions between the intervention and comparison groups (RR = 1.0, 95% CI = 0.68–1.46, P = .99). The integration of GNS expertise through the RACIP intervention may be one approach to support staff to provide optimal care and potentially improve resident health.  相似文献   
676.
Creating a socially conscious educational environment is an imperative if health care practitioners are to have a significant impact on health inequities. The effects of practitioner bias, prejudice, and discrimination on health and health outcomes have been well documented in the literature. Individuals being trained to provide health care will be entering into an increasingly diverse world and must be equipped with the appropriate knowledge and skills in order to meet the needs of those seeking their care. Cultural competency training in medical education has evolved over the past 15 years since the Institute of Medicine's 2002 report, Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care. As research on the effectiveness of this training has emerged, several authors have called for the integration of antiracism training into the cultural competency curriculum, but few have found effective ways of doing so. This article describes the approach of one midwifery program in order to inform clinical education programs across the spectrum of health care practitioners.  相似文献   
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The Imai rat is a model of spontaneous focal glomerulosclerosis, which leads to heavy proteinuria, hyperlipidemia, hypertension, and progressive renal failure. Treatment with AT1 blockers (ARBs) ameliorates proteinuria, hyperlipidemia, and nephropathy in this model. Progression of renal disease in 5/6 nephrectomized rats is associated with activation of the intrarenal angiotensin system, up-regulation of the oxidative, inflammatory, and fibrogenic pathways, and impaired activity of nuclear factor-erythroid-2-related factor 2 (Nrf2), the master regulator of genes encoding antioxidant molecules. We hypothesized that progressive nephropathy in the Imai rat is accompanied by oxidative stress, inflammation, and impaired Nrf2 activation and that amelioration of nephropathy with AT1 receptor blockade in this model may be associated with the reversal of these abnormalities. Ten-week-old Imai rats were randomized to the ARB-treated (olmesartan, 10 mg/kg/day for 24 weeks) or vehicle-treated groups. Sprague-Dawley rats served as controls. At 34 weeks of age Imai rats showed heavy proteinuria, hypoalbuminemia, hypertension, azotemia, glomerulosclerosis, tubulointerstitial inflammation, increased angiotensin II expressing cell population, up-regulations of AT1 receptor, AT2 receptor, NAD(P)H oxidase, and inflammatory mediators, activation of nuclear factor-κB and reduction of Nrf2 activity and expression of its downstream gene products in the renal cortex. ARB therapy prevented nephropathy, suppressed oxidative stress and inflammation, and restored Nrf2 activation and expression of the antioxidant enzymes. Thus progressive focal glomerulosclerosis in the Imai rats is associated with oxidative stress, inflammation, and impaired Nrf2 activation. These abnormalities are accompanied by activation of intrarenal angiotensin system and can be prevented by ARB administration.  相似文献   
679.

Objective

Identification of key molecular changes occurring during epileptogenesis provides better understanding of epilepsy and helps to develop strategies to modify those changes and thus, block the epileptogenic process. Gap junctional communication is thought to be involved in epileptogenesis. This communication can be affected by changes in expression of gap junctional protein subunits called connexins (Cxs). One of the main brain regions involved in epileptogenesis is the hippocampus in which there is a network of gap junctional communication between different cell types.

Method

Cx36 and Cx43 expressions at both mRNA and protein level were measured in rat hippocampus during epileptogenesis in the kindling model of epilepsy.

Results

Cx36 expression at both mRNA and protein level was upregulated during acquisition of focal seizures but returned to basal level after acquisition of secondarily-generalized seizures. No change in Cx43 gene and protein expression was found during kindling epileptogenesis.

Conclusion

These results further point out the significance of Cx36 as a target to modify epileptogenic process and to develop antiepileptogenic treatments.  相似文献   
680.

Background and Aims

Palliation therapy is the only available therapeutic method for most patients with tumor-induced obstructive jaundice. Metallic stents are now performed percutaneously as an alternative route to the endoscopic approach. It is widely accepted because of its safety, good patency rate, and minimal invasiveness. This study was designed to evaluate the long-term results of metallic self-expandable stent insertion in patients with malignant stenosis of the biliary tree.

Methods

It is a longitudinal study of patients with percutaneously biliary stenting from September 2005 to March 2009. The patients had unresectable malignant biliary obstruction with unsuccessful endoscopic stenting and access. Percutaneous transhepatic cholangiogram performed after adequate local anesthesia, under sonographic or fluoroscopic guidance. Stenting or balloon dilation was performed through the hydrophilic guide wire. Among 50 patients, 45 stents were placed in biliary tree stenosis sites. Patients’ follow-up was during the first, second, third, and then the sixth month after insertion of biliary stents. Stent patency was considered successful in our patients, when there were no lab results or sonographic appearance of biliary tree obstruction.

Results

10(20%) patients’ stent placement treatment failed because of unsuccessful technical procedure. The stenosis of biliary tract was complete and passage of guide wire was not possible through the tumor growth. 6 (15 %) patients with successful stent placements died within one month (mean, 22 days). Total serum bilirubin resolved to below 1.5 mg/dl within 30 days for 36 (90%) patients with successful stent placements. Early complications not leading to death occurred in 28% of cases. The mean survival time for all patients who underwent stent placement was 140 days (16-420days). The mean patency rate for all stents was 147 days.

Conclusions

Percutaneous biliary stenting is a safe procedure with few technical complications and a high success rate of palliation for patients with malignant biliary jaundice. Early complications are mostly managed conservatively and death is mainly due to systemic effects of the malignant disease.  相似文献   
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