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Background: Most patients with congestive heart failure (CHF) develop pulmonary venous hypertension, but right ventricular afterload is frequently further elevated by increased pulmonary vascular resistance. To investigate whether inhalation of a vasodilatory phosphodiesterase-3 inhibitor may reverse this potentially detrimental process, the authors studied the effects of inhaled or intravenous milrinone on pulmonary and systemic hemodynamics in a rat model of CHF.

Methods: In male Sprague-Dawley rats, CHF was induced by supracoronary aortic banding, whereas sham-operated rats served as controls. Milrinone was administered as an intravenous infusion (0.2-1 [mu]g [middle dot] kg body weight-1 [middle dot] min-1) or by inhalation (0.2-5 mg/ml), and effects on pulmonary and systemic hemodynamics and lung water content were measured.

Results: In CHF rats, intravenous infusion of milrinone reduced both pulmonary and systemic arterial blood pressure. In contrast, inhalation of milrinone predominantly dilated pulmonary blood vessels, resulting in a reduced pulmonary-to-systemic vascular resistance ratio. Repeated milrinone inhalations in 20-min intervals caused a stable reduction of pulmonary artery pressure. No hemodynamic effects were detected when 0.9% NaCl was administered instead of milrinone or when milrinone was inhaled in sham-operated rats. No indications of potentially adverse effects of milrinone inhalation in CHF, such as left ventricular volume overload, were detected. Moreover, lung edema was significantly reduced by repeated milrinone inhalation.  相似文献   

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Introduction  

Cattle are an important source of allergens in the working area of farmers. Asthma caused by cow allergens is a significant occupational problem. Yet in allergological testing, the results of in vivo and in vitro diagnostic tests are often inconsistent even in cases with clearly cattle-related symptoms.  相似文献   
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Immune defense capacity differs between men and women. Whereas men are more prone to infection and sepsis, women more commonly develop autoimmune diseases. We investigated the difference in cytokine secretion between males and females in response to different immune stimuli. Whole blood from 154 healthy volunteers (age 24 +/- 5.2; 82 females, 72 males) was collected within 2 h on 2 consecutive days. Blood from males produced significantly more tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, and IL-8 than blood from females in response to a high concentration of either lipopolysaccharide (LPS) or lipoteichoic acid (LTA), whereas IL-10 and interferon-gamma (IFN-gamma) secretion did not differ. Normalization of cytokine measurement to individual monocyte counts cancelled these differences for all parameters except TNF-alpha. Stimulation with a lower concentration of LPS (100 pg/mL) produced even stronger differences in cytokine release, which were not cancelled by normalization to the producing cells. The coefficients of variation (CV) of the LPS-induced and LTA-induced cytokine responses were higher in blood from women than men for all parameters and stimuli measured. Thus, the stronger innate immune response of males in comparison to females appears to stem not only from a difference in monocyte counts but also from the steepness of the response curve.  相似文献   
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BACKGROUND: Cannabinoids present neurotoxic and neuroprotective properties in in vitro studies, inconsistent alterations in human neuroimaging studies, neuropsychological deficits, and an increased risk for psychotic episodes. METHODS: Proton magnetic resonance spectroscopy ((1)H-MRS), neuropsychological testing, and hair analysis for cannabinoids was performed in 13 male nontreatment-seeking recreational cannabis users and 13 male control subjects. RESULTS: A significantly diminished N-acetylaspartate/total creatine (NAA/tCr) ratio in the dorsolateral prefrontal cortex (DLPFC) was observed in cannabis users (p = .0003). The NAA/tCr in the putamen/globus pallidum region correlated significantly with cannabidiol (R(2) = .66, p = .004). Results of the Wisconsin Card Sorting test, Trail making Test, and D2 test for attention were influenced by cannabinoids. CONCLUSIONS: Chronic recreational cannabis use is associated with an indication of diminished neuronal and axonal integrity in the DLPFC in this study. As chronic cannabis use is a risk factor for psychosis, these results are interesting because diminished NAA/tCr ratios in the DLPFC and neuropsychological deficits were also reported in schizophrenia. The strong positive correlation of NAA/tCr and cannabidiol in the putamen/globus pallidum is in line with neuroprotective properties of cannabidiol, which were also observed in in vitro model studies of Parkinson's disease.  相似文献   
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Ohne ZusammenfassungBemerkungen zu der Arbeit vonW. Dieter: Über den Zusammenhang zwischen osmotischem Druck, Blutdruck, insbesondere Capillardruck und Augendruck nach neuen experimentellen und klinischen Untersuchungen. Arch. f. Augenheilk.96, 180. 1925.  相似文献   
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