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71.
The objective of this study was to investigate bacterial resistance trends, infection sites and the relationship between resistance and admittance to the intensive care unit (ICU). A total of 53,316 bacteria identified between 1999 and 2008 were evaluated. Multidrug resistance was characterized when gram-negative bacilli (GNB) presented resistance to two or more classes of antibiotics. Gram-positive cocci (CPC) were assessed for resistance to penicillin, oxacillin and vancomycin. GNB were the most common (66.1%) isolate. There was a 3.7-fold overall increase in multidrug resistant GNB over the study period; Acinetobacter baumanii and Staphylococcus aureus were the most prevalent. Highest increases were recorded for Klebsiella pneumoniae (14.6-fold) and enterococci (73-fold). The resistance rates for GNB and GPC were 36% and 51.7%, respectively. Most multidrug resistant GNB and GPC were recovered from ICU patients (p-value < 0.001). Vancomycin-resistant enterococci were isolated during this decade with an increase of 18.7% by 2008. These data confirm the worldwide trend in multidrug bacterial resistance.  相似文献   
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Background:   The administration of epidural and spinal clonidine has demonstrated an antinociceptive effect in animals and humans. For that reason, its spinal administration has been proposed as an adjuvant in chronic pain management. However, there is limited information about its possible neurotoxic effect after its continuous neuraxial administration.
Method:   Twelve male Wistar rats were randomly divided into two groups. Using an osmotic mini-pump a continuous infusion of intrathecal clonidine, (21.4 micrograms/day, Group A) or saline solution (Group B), was administered for 14 consecutive days. For evaluating the neurological damage a neuropathological analysis of the spinal cord was performed by light microscopy.
Results:   Neurohistopathologic examination of the spinal cord specimens failed to show evidence of neurotoxic damage in either group.
Conclusions:   These findings showed that continuous intrathecal administration of clonidine did not produce evidence of histological neurotoxicity; therefore it is possible that continuous administration of intrathecal clonidine might be a safe option for treatment of chronic intractable pain; however, further investigations are necessary for evaluating diverse doses and periods of time, and to define its possible behavioral effects.  相似文献   
74.
This is the case of a 27 years-old woman with signs and symptoms of severe untreatable congestive heart failure, anemia, gingival mucosa ulcers, photosensitivity and alopecia. The electrocardiographic, echocardiographic, angiographic and hemodynamic data oriented the diagnosis of restrictive cardiomyopathy, mitral insufficiency secondary to mitral prolapse and bi-atrial dilation. The histologic study of the endomyocardial biopsy, performed during catheterization, showed signs of endomyocardial fibrosis, and immunological analysis was compatible with systemic lupus erythematosus. As far as we know, this is the first case of endomyocardial fibrosis (Davies disease) associated with systemic lupus erythematosus published in the medical literature. The etiology of Davies disease remains unrevealed and its association with systemic lupus erythematosus suggest a probable autoimmune origin.  相似文献   
75.
Summary Two-dimensional echocardiography is a useful noninvasive tool for diagnosing intrapericardial tumors as a cause of respiratory distress or abnormal cardiomediastinal shadow on chest x-ray. Early recognition of these tumors within the pericardium is important since surgical removal is often curative. Cardiac cineangiography is unnecessary to delineate further the tumor and should be reserved for those in which associated intracardiac defects are suspected.  相似文献   
76.
Diversity among Lutzomyia longipalpis populations in Venezuela was characterized using 2 methods: larval mouthpart morphology-morphometry and isoenzyme electrophoresis. Analysis of the results suggested the presence of 2 morpho-genotypes. The mentum, maxillary comb, mandibular ventral teeth, and adenylate kinase and hexokinase enzyme-encoding loci suggested that a population from the northwestern Coriano System (Curarigua) is a distinct lineage within the L. longipalpis complex. Three widely separated populations from the Llanos (savanna), Andes, and northcentral Coastal Cordillera showed no significant substructure. These studies provide morphologic markers that are congruent with genetic data and suggest that the morphologic markers may be used to characterize and differentiate populations within this species complex.  相似文献   
77.
OBJECTIVE: To compare the amount of National Institutes of Health (NIH) funding provided to departments of surgery with that provided to other major clinical departments, to examine the relationship between peer-review activity and funding success, and to compare trends in participation in the peer-review process between surgeons and representatives from other clinical departments. SUMMARY BACKGROUND DATA: Surgical research has made enormous contributions to human health. This work is fundamentally dependent on fair and unbiased distribution of extramural research funds from the NIH. To date, no published report has examined the relative distribution of extramural support between departments of surgery and other major clinical departments. METHODS: Data regarding funding trends and peer-review activity were obtained from the NIH and compared between departments of surgery and four nonsurgical departments (medicine, psychiatry, pediatrics, neurology). Award data were examined during 1996 to 2001. Participation trends were examined during 1998 to 2000. RESULTS: Success rates of surgical proposals were significantly lower than nonsurgical proposals. Differentials in success rates were greatest for proposals assigned to the National Cancer Institute, although relative underfunding for surgical research spanned all major institutes. Awards for surgical grants averaged 5% to 27% less than nonsurgical grants). Surgeons exhibited 35% to 65% less peer-review activity relative to nonsurgeons when normalized to grant submission activity. Overall, surgeons participated on sections where they made up a relatively smaller proportion of total review members compared to nonsurgeons. CONCLUSIONS: Surgical grant proposals are less likely to be funded and carry significantly smaller awards compared to nonsurgical proposals. Relatively fewer surgeons participate in the review process, and those who do are more likely to be in the minority within study sections. Multiple strategies are needed to address these trends and level the playing field for surgical research.  相似文献   
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Nephrotic syndrome (NS) is characterized by the presence of proteinuria and hyperlipidemia. However, ingestion of soy protein has a hypolipidemic effect. The present study was designed to determine whether the ingestion of a 20% soy protein diet regulates the expression of hepatic sterol regulatory element binding protein (SREBP)-1, fatty acid synthase (FAS), malic enzyme, beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA) reductase (r) and synthase (s), and LDL receptor (r), and to assess whether soy protein improves lipid and renal abnormalities in rats with chronic NS. Male Wistar rats were injected with vehicle or with puromycin aminonucleoside to induce NS and were fed either 20% casein or soy protein diets for 64 d. NS rats fed 20% soy protein had improved creatinine clearance and reduced proteinuria, hypercholesterolemia, hypertriglyceridemia, as well as VLDL-triglycerides and LDL cholesterol compared with NS rats fed the 20% casein diet. In addition, the soy protein diet decreased the incidence of glomerular sclerosis, and proinflammatory cytokines in kidney. Ingestion of the soy protein diet by control rats reduced the gene expression of SREBP-1, malic enzyme, FAS and increased HMG-CoAr, HMG-CoAs and LDLr. However, NS rats fed either casein or soy protein diets had low insulin concentrations with reductions in SREBP-1, FAS and malic enzyme expression compared with control rats fed the casein diet. NS rats fed the soy diet also had lower HMG-CoAr and LDLr mRNA levels than NS rats fed casein. In conclusion, the beneficial effects of soy protein on lipid metabolism are modulated in part by SREBP-1. However, in NS rats, the benefit may be through a direct effect of this protein on kidney rather than mediated by changes in expression of hepatic lipid metabolism genes.  相似文献   
80.
The interpretation of the huge number of results in schizophrenia research using neuroimaging is uncertain. However, the simultaneous use of complimentary data obtained with these techniques may yield more relevant information in this regard. In this paper we present a series of studies performed by our group in two schizophrenic samples with the use of structural (magnetic resonance imaging, MRI), functional [glucose positron emission tomography (PET) and N-acetyl-aspartate (NAA) magnetic resonance spectrocopy] and neurophysiological techniques (the P300 event-related potential). Transversal and longitudinal measurements were performed.The integrated vision of the results so obtained allows us to propose the hypothesis of a neurodevelopmentally determined state of prefrontal disinihibition, in which the degree of atrophy would directly relate to the metabolic rate. This state would already be present in the first stages of illness and could have neurotoxic consequences in the long term. This would explain the findings of an association between sulcal cerebrospinal fluid (CSF) and illness duration and decreased NAA levels in chronic but not in recent-onset cases. The prefrotnal disinhibition would overstimulate the limbic system and the hippocampus would become overactivated, the metabolic rate at this level being inversely related to P300 amplitude. Clozapine showed a more selective and intense action on that hyperactive metabolic tone than haloperidol.  相似文献   
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