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101.
Idiopathic dilated cardiomyopathy (IDC) is a distinct disease of the myocardium, of unknown etiology. The disease can occur acutely, or evolve in a subacute fashion. IDC is often associated with a substantial impairment of ventricular function, which may recover over time. Although spontaneous recovery of LV function occurs in 20%-45% of newly diagnosed patients, the majority of patients do not do well. IDC has an average 5-year mortality of 20%. Abnormalities of energetics, perfusion, and adrenergic control of the myocardium are markers of the status of LV dysfunction. As the heart fails, changes occur in the production and catabolism of high-energy substrates, the efficiency of mitochondrial oxidative processes, the distribution of resting perfusion and coronary vasodilating capacity and the adrenergic receptor density and function. This article reviews the information provided by metabolic and receptor imaging in patients with IDC, and the role the data may play in patient management.  相似文献   
102.
This study was conducted to examine the oral condition and the salivary and microbiological parameters associated with dental caries in 62 children with cerebral palsy, who came from households of low socioeconomic status (Study Group). This group had mixed (6 to 11 years old) and permanent (11 to 16 years old) dentition. Dental examinations were performed to measure dental caries, plaque index, salivary levels of mutans streptococci and lactobacilli, salivary flow rate, pH of stimulated saliva, and buffer capacity of saliva. A group of 67 non-handicapped children from similar socioeconomic backgrounds also were examined using these parameters (Control Group). Data were analyzed statistically by non-parametric tests and by correlation. The results showed that children with cerebral palsy who had permanent dentitions had a higher mean decayed, missing and filled surfaces index, as well as a higher plaque index for both sexes. Microbiological examination revealed higher levels of mutans streptococci among Study Group subjects with mixed dentition than in the Control Group. Also, lactobacillus counts were higher in the Study Group, regardless of sex or dentition. With respect to salivary flow rate, pH and buffering capacity, lower mean values were obtained for the Study Group.  相似文献   
103.
Increased (intra)renal activity of the renin-angiotensin system may cause a persistent increase in renovascular resistance and intraglomerular pressure in patients with diabetes, thus contributing to the development of diabetic renal damage. The effect of chronic angiotensin II subtype 1 receptor blockade on (intra)renal hemodynamics in patients with type 2 diabetes was examined in a double-blind parallel group study. Patients were treated with 40 mg of olmesartan (n = 19) or placebo (n = 16), and renal hemodynamics were assessed before and after 12 wk of treatment using inulin and para-aminohippurate clearance techniques. Olmesartan significantly reduced 24-h ambulatory systolic and diastolic BP (both P < 0.05). In parallel, effective renal plasma flow increased significantly from 602 +/- 76 to 628 +/- 87 ml/min per 1.73 m(2), whereas filtration fraction and renovascular resistance decreased significantly (all P < 0.05). With placebo treatment, effective renal plasma flow decreased and filtration fraction increased significantly (both P < 0.05). GFR was not affected by both treatments. Active plasma renin concentration increased considerably (P < 0.05) with olmesartan therapy but remained unchanged with placebo treatment. Nitric oxide metabolism (plasma nitrate and nitrite) and asymmetric dimethylarginine blood levels were not affected by olmesartan and placebo therapy. In contrast, plasma 8-isoprostane 15(S)-8-iso-prostaglandin F(2a) concentration, a biochemical marker of oxidative stress, decreased significantly (P < 0.05) with olmesartan treatment. Chronic angiotensin II subtype 1 receptor blockade decreases (intra)renal vascular resistance and increases renal perfusion despite significant BP reduction. In addition, it significantly reduces oxidative stress. These effects of angiotensin II receptor antagonists may contribute to their beneficial long-term renal effects in patients with type 2 diabetes.  相似文献   
104.
Electrophysiological and metabolic activities in brain tissue preparations maintained in vitro may be influenced by the persistent effect of anesthetic drugs utilized during tissue dissection. In order to clarify this issue, we studied elimination kinetics of the barbiturate thiopental from the brain parenchyma in the isolated guinea pig brain maintained in vitro, arterially perfused with a protein-free saline solution [M. de Curtis, G. Biella, C. Buccellati, G. Folco, Simultaneous investigation of the neuronal and vascular compartments in the guinea pig brain isolated in vitro, Brain Res. Protoc. 3 (1998) 21-28]. At the onset of anesthesia induced by a single i.p. injection of 125 mg/kg thiopental, the brain concentration of the drug, measured by high-performance liquid chromatographic assay, was 44.22+/-5.1 mg/L (mean+/-S.E.; n=7). After 30 min of arterial perfusion in vitro with a thiopental-free solution, the cerebral levels of the barbiturate decreased to 2.03+/-0.56 mg/L (n=3), and reached values close to zero within 1 h. No significant changes in thiopental elimination curve were observed when in vitro perfusion rate was either increased or decreased. The study demonstrates that thiopental is rapidly eliminated from the brain tissue with a mono-exponential kinetic. It can be concluded that barbiturate anesthesia utilized during brain dissection is not likely to influence activities recorded from the in vitro isolated brain preparation.  相似文献   
105.
Diabetic nephropathy is the main cause of morbidity and mortality in patients with Type 1 diabetes mellitus. Microalbuminuria has been established as a risk factor for the development and the progression of diabetic renal disease. A strong demand exists for better technologies to provide accurate diabetic nephropathy risk estimates before renal functional or structural disturbances already become established. Here, we present the application of a novel proteomics technology identifying urinary polypeptides and proteins. In this pilot study, we investigated 44 Type 1 diabetic patients with more than 5 years of diabetes duration compared with an age-matched control group. Random spot urine samples were examined utilizing high-resolution capillary electrophoresis (CE), coupled to mass spectrometry (MS). More than 1000 different polypeptides, characterized by their separation time and mass, were found between 800 Da and 66.5 kDa. Mathematical analysis revealed specific clusters of 54 polypeptides only found in Type 1 diabetic patients and an additional 88 polypeptides present or absent in patients with beginning nephropathy defined by the albumin-to-creatinine ratio (ACR; >35 mg/mmol). We observed polypeptide patterns characteristic for healthy controls and diabetic patients and subdivision of patients according to the excretion of polypeptides typical for diabetic nephropathy. Our study revealed that the urinary proteome contains a much greater variety of polypeptides than previously recognized and demonstrated the successful application of a novel high-throughput technology towards the human urinary proteome. Future prospective studies with the application of this technique may enable the earlier and more accurate detection of individuals at high risk to develop diabetic nephropathy.  相似文献   
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109.
BACKGROUND: Coronary care units (CCUs) currently treat a variety of diseases, but little is known about the effectiveness of CCUs on heart conditions other than acute myocardial infarction. OBJECTIVES: The objectives of this study were to evaluate the association between direct admission to CCUs and the risk of inhospital death in patients with heart disease, to investigate factors affecting direct admission to a CCU, and to assess the effect of CCU admission on the use of invasive procedures in patients with arrhythmias. RESEARCH DESIGN: We conducted a retrospective analysis of discharge-abstract data from Lazio, Italy, hospitals. We used logistic regression, propensity score, and instrumental variable analysis to compare inhospital risk of death between patients admitted to CCUs and to ordinary wards in 13 different groups of heart disease. We used linear regression to study the association between the rate of CCU admission and the relative risk of death. RESULTS: The study included 181,049 heart disease admissions, of which 8620 were admitted to CCUs (4.8%). Risk of death was significantly lower in patients admitted directly to CCUs for "acute myocardial infarction" (odds ratio [OR], 0.57), "acute ischemic heart disease" (OR, 0.55), and "other arrhythmias" (OR, 0.56). Mortality ORs were inversely related to the rate of CCU admission. CCU patients with arrhythmias received more invasive procedures (OR, 2.70) than non-CCU patients. CONCLUSION: Direct admission to a CCU is associated with a decrease in mortality for patients with "acute myocardial infarction," "acute heart ischemia," and "other arrhythmias." Patients most likely to benefit from CCU care are preferentially admitted to CCUs. CCUs make larger use of invasive procedures than ordinary wards.  相似文献   
110.
Reflection about the way of distributing public resources in the area of health and the ensuing consequences. The fairness of distributive justice is questioned. We propose a contextual reading of the official figures through interrelations that make it possible to understand the meaning of government figures. AIDS and Diabetes, which have been chosen as paradigms, represent, respectively, the groups of Transmitted Diseases and Non-Transmitted Diseases. The official figures relating to the two diseases are correlated in some precise aspects such as expenses on drugs, prevalence, and evolution of mortality rates. We alert to the remarkable differences in official attention between these two diseases and to the consequences suffered by people affected with Diabetes and other nontransmitted diseases, arising from the insufficiency of public resources allotted for their health care.  相似文献   
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