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131.
OBJECTIVE: To determine prevalence and severity of systemic arterial hypertension and proteinuria in dogs with naturally developing hyperadrenocorticism and to determine whether these abnormalities resolve with adequate management of the disease. DESIGN: Case series and cohort study. ANIMALS: 77 dogs with naturally developing hyper-adrenocorticism examined once; 15 dogs examined before and after treatment. RESULTS: Among dogs examined only once, hypertension was diagnosed in 21 of 26 dogs with untreated pituitary-dependent hyperadrenocorticism (PDH), 17 of 21 with inadequately controlled PDH, 8 of 16 with well-controlled PDH, 10 of 10 with an untreated adrenocortical tumor, and 0 of 4 that had undergone adrenalectomy because of an adrenocortical tumor. Untreated dogs and dogs with inadequately controlled PDH had significantly higher blood pressures than did other dogs. Proteinuria was documented in 12 of 26 dogs with untreated PDH, 5 of 16 with inadequately controlled PDH, 3 of 14 with well-controlled PDH, 5 of 8 with an untreated adrenocortical tumor, and 1 of 3 that had undergone adrenalectomy. Dogs with untreated PDH and dogs with an untreated adrenocortical tumor had higher urine protein/creatinine ratios than did dogs with well-controlled PDH. Among dogs evaluated before and after treatment, blood pressure and urine protein/creatinine ratio did not change in 8 dogs with inadequately controlled hyperadrenocorticism, but decreased in 7 dogs with well-controlled disease. CLINICAL IMPLICATIONS: Results suggest that systemic hypertension and proteinuria are common in dogs with untreated hyperadrenocorticism and that successful treatment of hyperadrenocorticism will result in resolution of these abnormalities in many, but not all, dogs.  相似文献   
132.
Evaluation of the relative efficacy of three screening instruments for depression and anxiety in a group of stroke patients was undertaken as part of the Perth community stroke study. Data are presented on the sensitivity and specificity of the Hospital Anxiety and Depression Scale (HAPS), the Geriatric Depression Scale and the General Health Questionnaire (GHQ) (28-item version) in screening patients 4 months after stroke for depressive and anxiety disorders diagnosed according to DSM-III criteria. The GHQ-28 and GDS but not the HADS depression, were shown to be satisfactory screening instruments for depression, with the GHQ-28 having an overall superiority. The performance of all 3 scales for screening post-stroke anxiety disorders was less satisfactory. The HADS anxiety had the best level of sensitivity, but the specificity and positive predictive values were low and the misclassification rate high.  相似文献   
133.
The ability of histamine H3 receptor ligands to interact with 5-HT3 receptors in NG108-15 cells was studied using the whole cell patch clamp recording technique. Imetit, a histamine H3 receptor agonist, generated inward currents and exhibited weak partial agonist activity at the 5-HT3 receptor (EC50 = 11.8 microM). Imetit-induced currents were slow to desensitize and at a high concentration reduced in size. The histamine H3 receptor antagonists iodophenpropit and thioperamide did not generate inward currents but were able to inhibit 5-hydroxytryptamine (5-HT) responses with an IC50 of 1.57+/-0.3 microM and 13.7+/-3.5 microM, respectively. Thioperamide is probably a non-competitive antagonist which may have more than one binding site on the receptor.  相似文献   
134.
8E5 is a chronically human immunodeficiency virus (HIV)-infected human T cell line, which we have previously shown to be extremely susceptible to hydrogen peroxide (H2O2)-induced apoptosis due to a HIV-associated catalase deficiency. Here we report that HIV gene expression additionally renders 8E5 cells 10-fold more sensitive than either uninfected A3.01 cells or HIV-infected but nonexpressing 8E5L cells to killing by 15-hydroperoxyeicosatetraenoic acid (15-HPETE), as well as several other hydroperoxy fatty acids. Whereas the viability of A3.01 and 8E5L cells was relatively unaffected by exposure to 10 microM 15-HPETE, similarly treated 8E5 cells underwent apoptosis, as demonstrated by morphological changes and the presence of fragmented DNA. The unique susceptibility of 8E5 cells was attributable to their inability to convert 15-HPETE to 15-hydroxy-eicosatetraenoic acid (15-HETE) owing to a marked reduction in glutathione peroxidase activity. Since oxidized lipids have been reported to accumulate in oxidatively stressed, HIV-infected individuals, a HIV-associated glutathione peroxidase deficiency may contribute to the depletion of CD4 T cells that occurs in the acquired immune deficiency syndrome (AIDS).  相似文献   
135.
The aim of this study was to investigate the oxidative phosphorylation and additional adenosinetriphosphate (ATP) production mechanisms in mitochondria isolated from hypertrophied left ventricles of spontaneously hypertensive rats (SHR). Measurements of adenosinediphosphate (ADP)/ ATP and inorganic phosphate (Pi) carrier activities showed a significant reduction of Vmax values thus suggesting a general decrease of ATP supply in the hypertrophied ventricles. Investigation of mitochondrial enzyme activities showed 45% and 90% increases of adenylate-kinase and 80% and 110% increases of creatine-phosphokinase in 5- and 24-week-old SHR, before and after the development of the hypertensive state, respectively. The abnormalities found in SHR at the mitochondrial level suggest a profound rearrangement of energy production mechanisms in this model of left ventricular hypertrophy; whether the defects are determined genetically, and then worsen with the hypertensive state, remains to be determined.  相似文献   
136.
The concept of incremental value in prognosis and outcome of patients with coronary artery disease is important to the field of noninvasive imaging. Because these tests are expensive, they should be held to the standard of demonstrating a statistical improvement over the information provided by clinical assessment and treadmill testing. Responding to the demand for cost-effective applications of myocardial perfusion scintigraphy, a large amount of research has recently been devoted to defining specific patient subsets in which incremental value exists for scintigraphy. Subsets thus far demonstrated to benefit incrementally include those men and women referred for possible coronary artery disease, with known coronary artery disease, and after percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, unstable angina, or recent infarction. Incremental cost savings also apply to these subsets except for patients with normal ECGs at rest and less than 15% likelihood for significant coronary artery disease.  相似文献   
137.
Cytokines play an essential role as mediators of the immune response. They usually function as part of a network of interactive signals that either activate, enhance, or inhibit the ensuing reaction. An important contribution of this cytokine cascade is the induction of an inflammatory response that recruits and activates subsets of leukocytes that function as effector cells in the response to the sensitizing antigen. Proinflammatory cytokines activate endothelial cells (EC) to express adhesion molecules and induce the release of members of the chemokine family, thus focusing and directing the inflammatory response to sites of antigen recognition. However, the vasculature of the central nervous system (CNS) is highly specialized and restricts the access of components of the immune system to the CNS compartment. In this review, we address the question as to whether endothelial cells in the CNS respond differently to specific cytokines known to induce either a proinflammatory effect or a regulatory effect in systemic vascular beds.  相似文献   
138.
335 patients with obliterative diseases of arteries of the low extremities were examined. Results of motor rehabilitation depend on the severity of post-amputation defect of the extremity and functional condition of the stump. The lower is the level of the amputation the higher is the effectiveness of the rehabilitational measures. Ischemia of femoral stump springs up rarely but its course is mare severe than ischemia of the stump of the shin, which is confirmed by the data of clinical examination, investigation of biochemical parameters of the blood and mortality rate. For prophylaxis of ischemia of the stump it is suggested simultaneously with the amputation of the extremity to perform reconstructive procedures on the arteries, aimed at restoration of blood flow through the profound femoral artery. This policy provides the possibility to form a long functional stump of the extremity and to improve results of motor rehabilitation.  相似文献   
139.
Rats experience anorexia and reduction or cessation in growth after being provided a zinc-deficient diet. While zinc deficient, intake levels may be reduced 50% or more compared to control rats. In the present report, diurnal food intake patterns of male Sprague-Dawley rats were measured during zinc deficiency. In Study 1, rats consuming a modified AIN-93 diet were tested during the dark phase using an automated food weighing system. In zinc-deficient animals (Zn-), the onset of the first meal of the dark phase was delayed compared to zinc-adequate rats (Zn+; 106+/-47 vs. 23+/-5 min; p<0.05) and the number of meals consumed during the dark phase was reduced in Zn- vs. Zn+ rats (3.9+/-0.5 vs 7.1+/-0.4; p<0.05). In Study 2, diurnal food intake patterns were tested using a three-choice macronutrient self-selection paradigm of carbohydrate-, protein-, and fat-containing diets made deficient or adequate in zinc (1 or 30 mg Zn/kg diet). Food intake was recorded in the early-, mid-, late-dark period (4 h each) and light period (12 h). Carbohydrate intake was 70% of total intake of both Zn+ and Zn- rats during the first 5 days, but decreased significantly to 50% in the Zn- group during the last 5 days. Fat intake increased significantly in the Zn- group during the last 5 days. This increase was the result of 4 of 15 Zn- rats increasing their intake of fat significantly. Results of this study indicate that zinc status alters dark phase and macronutrient selection patterns by delaying consumption of the initial meal of the dark phase, reducing the average meal number and by changing the dominant macronutrient preference of some Zn- rats.  相似文献   
140.
Experimental systems based on immunization with plasmid DNA or immune-stimulating complexes were used to delineate the requirements for generation of protective immunity against murine leishmaniasis. Vaccination with plasmid DNA encoding the host-protective Leishmania major parasite surface Ag-2 primed for an essentially exclusive Th1 response that protected mice against L. major infection. In contrast, parasite surface Ag-2 in immune-stimulating complexes generated an immune response with mixed Th1-like and Th2-like properties that was not protective despite the activation of large numbers of CD4+ T cells secreting IFN-gamma. These results indicate that a Th1 response is sufficient to protect against cutaneous leishmaniasis, but the induction of a simultaneous Th2 response abrogates the Th1 effector function. DNA vaccines may therefore have an advantage for diseases in which protection depends on the induction of Th1 responses.  相似文献   
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