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171.
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing.  相似文献   
172.
Radiolabeled chemotactic peptides have been studied for their applicability to the visualization of infectious and inflammatory foci. Because a radiolabeled leukotriene B4 (LTB4) antagonist allowed visualization of intramuscular E. coli abscesses in rabbits within a few hours after injection, we decided to test the imaging characteristics of this agent in a more clinically relevant model of pulmonary aspergillosis. The pharmacokinetics and imaging characteristics of the 111In-labeled LTB4 antagonist DPC11870 were studied in New Zealand White rabbits with experimental pulmonary aspergillosis infection. The imaging characteristics of 111In-DPC11870 were compared with those of 67Ga-citrate, a radiopharmaceutical commonly used to detect pulmonary infections in patients. METHODS: Pulmonary aspergillosis was induced in the left lung of rabbits by intratracheal inoculation of 1 x 10(8) conidia of Aspergillus fumigatus. Three days after the inoculation, the rabbits received 111In-DPC11870 or 67Ga-citrate intravenously. Images were acquired at several time points up to 24 h after injection. RESULTS: Pulmonary aspergillosis was visualized with both agents. Images acquired after injection of 111In-DPC11870 showed uptake in the pulmonary lesions from 6 h after injection. Because of accumulation at the site of infection and clearance from the background, the images improved with time. Region-of-interest analysis at 24 h after injection revealed infected lung-to-normal lung ratios of 5.0 +/- 1.5 for 111In-DPC11870 and 2.9 +/- 0.6 for 67Ga-citrate. CONCLUSION: The radiolabeled LTB4 antagonist DPC11870 clearly delineated experimentally induced pulmonary aspergillosis in rabbits. Images acquired at 24 h after injection of 111In-DPC11870 were superior to those obtained after injection of 67Ga-citrate.  相似文献   
173.

Objectives  

Recovery opportunities allow employees to recuperate from work and diminish load effects. The aims of this study are to present a scale for measuring recovery opportunities, study its psychometric properties and its relationship with health.  相似文献   
174.
BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium.  相似文献   
175.
OBJECTIVE: To determine whether inhaled corticosteroids should be prescribed to patients with milder forms of asthma and whether markers of airway inflammation should be considered when making therapy decisions. DATA SOURCES: A PubMed search was performed of the English-language literature published in the preceding 10 years (January 1, 1993, through December 31, 2003) concerning epidemiology, pathophysiology, therapy, and prognosis of mild intermittent asthma, with asthma, mild, and intermittent as indexing terms. STUDY SELECTION: All relevant studies including author's expert opinions were selected. RESULTS: Several studies have addressed the question of a possible benefit of maintenance therapy (ie, inhaled steroids) in patients with mild intermittent asthma. Although a diminishing effect on airway inflammation has been widely demonstrated, even in patients with mild disease, the impact of inhaled steroids on the long-term prognosis is much less clear. For patients with mild disease who are long-term inhaled steroid users, alternative therapy strategies, including low-dose inhaled steroids and leukotriene receptor antagonists, have been advocated. CONCLUSIONS: Mild intermittent asthma is a disease characterized not only by infrequent symptoms and normal lung function but also by chronic airway inflammation, possibly resulting in irreversible airflow limitation if left unattended. Therefore, maintenance therapy, such as (low-dose) inhaled steroids or leukotriene receptor antagonists, should be considered in patients with mild disease. Future studies should give more insight into the impact of prolonged anti-inflammatory therapy on the long-term prognosis of mild intermittent asthma patients. Whether results from these studies will justify a more aggressive treatment for these patients remains to be answered.  相似文献   
176.
ContextZD4054 is a specific endothelin A (ETA) receptor antagonist being investigated for the treatment of hormone-resistant prostate cancer (HRPC). ZD4054 binds specifically to the ETA receptor, with no detectable activity at the ETB receptor. In preclinical studies, ZD4054 inhibited endothelin (ET-1)-mediated changes in cellular invasiveness in vitro, and inhibited angiogenesis and growth of tumour xenografts in vivo. Consistent with its specific binding profile, ZD4054 inhibited ETA-receptor-mediated antiapoptotic events while allowing ETB-receptor-mediated proapoptotic signalling.Evidence acquisitionThe preclinical and clinical activity of ZD4054 is reviewed.Evidence synthesisIn the clinical setting, stable levels of circulating ET-1 following single ZD4054 doses up to 240 mg demonstrated the absence of ZD4054 activity at the ETB receptor. ZD4054 is cleared principally via the urine, with a terminal elimination half-life of approximately 8–12 hours and with little accumulation after once-daily oral dosing.In a Phase 2 trial, patients with metastatic HRPC who were pain free or mildly symptomatic for pain were randomized to once-daily oral tablets of ZD4054 10 mg (n = 107), or 15 mg (n = 98), or matched placebo (n = 107). ZD4054 was generally well tolerated in this population, with an adverse effect profile consistent with its known pharmacological activity. The most common adverse effects were headache, peripheral oedema and nasal congestion. At the primary analysis there was no statistically significant difference in time to progression between the ZD4054-treated groups and placebo (hazard ratio [HR]: ZD4054 10 mg, 0.88 [80% CI 0.71, 1.09]; ZD4054 15 mg, 0.83 [0.66, 1.03]). However, a promising signal for prolonged overall survival was observed, which was sustained at a subsequent analysis (HR versus placebo: ZD4054 10 mg, 0.55 [80% CI 0.41, 0.73]; ZD4054 15 mg, 0.65 [0.49, 0.86]).ConclusionsThese results support the strategy of targeting the ETA receptor in prostate cancer, and mandate further investigation of ZD4054 in Phase 3 clinical trials.  相似文献   
177.
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration.  相似文献   
178.
179.
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization.  相似文献   
180.
Trauma und Berufskrankheit - Die Vermeidung gepuderter Latexhandschuhe gilt als wichtige Maßnahme zur Prävention von latexbedingten Haut- und Atemwegsallergien bei Beschäftigten im...  相似文献   
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