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We report the case of an enormous right atrial hemangioma in an asymptomatic 42-year-old woman. The diagnosis was made by echocardiogram after the patient was found to have an abnormal EKG during a routine medical exam. The hemangioma is the largest described in English literature. The tumor was surgically resected and the patient did well postoperatively. In this case report, we discuss the discovery of the tumor and treatment of our patient. A brief discussion of cardiac hemangiomas follows.  相似文献   
44.
The larvicidal activity of the juvenile hormone mimic pyriproxyfen was evaluated against the 4th larval instar of Culex pipiens under 5 constant temperatures in the laboratory. Toxicity of this insect compound increased with temperature. The 50% lethal concentrations ranged between 0.00111 ppm at 20 degrees C and 0.00013 ppm at 32 degrees C. A similar trend was observed for the 90% lethal concentrations, which varied from 0.00379 ppm to 0.00024 ppm at the 2 temperatures, respectively. Some effects of the compound were observed on the ultrastructure of the 4th-stage larval integument, where electron micrographs revealed the destruction of procuticle lamellae, formation of cuticular vacuoles, deformed mitochondria, and destruction of nuclear envelopes and the epidermal layer, in addition to an increase in electron-dense lysosomelike bodies.  相似文献   
45.
INTRODUCTION: A simple, rapid, sensitive, and enzyme-free analytical method for estimating scavenging of hydrogen peroxide (H2O2) was developed. METHODS: Peroxyoxalate chemiluminescence (POCL) was measured, using 9,10-diphenylanthracene as fluorophore. RESULTS: The chemiluminescence signal was found to be linear in response to increasing amounts of H2O2 in ethyl acetate/acetonitrile (9:1) (r2 = .9990), within a range of concentrations varying from 9.0 to 72.0 microM. In contrast, acetonitrile was highly unsuitable because of poor linearity (r2 = .3736) and poor signal stability. The linearity of POCL inhibition, as a measure of H2O2 scavenging, was tested employing well-known, lipid-soluble antioxidants, including beta-carotene, butylated hydroxytoluene (BHT) and alpha-tocopherol, and also the more polar flavonol quercetin, and the water-soluble L-ascorbic acid (AA). Under the experimental conditions, the corresponding values of H2O2 scavenging activity (SA(HP)) for quercetin, beta-carotene, alpha-tocopherol, and L-AA were 19.1 +/- 0.4, 70.9 +/- 20.1, 8.4 +/- 0.4, and 44.8 +/- 5.6 x 10(-3) microM(-1) DISCUSSION: The data establish the assay as a method for assessing the H2O2 quenching activity of lipid-soluble antioxidants.  相似文献   
46.
Persons preparing for careers in public health practice need a solid academic grounding in the principles of communicable disease control before arriving on the job. We have developed an introductory course in infectious disease control for the Master of Public Health program in Jerusalem, which includes instruction in the following broad areas: How do micro-organisms spread and cause disease? How do we investigate and control an outbreak? What are the basics of primary prevention by immunization and what can mass immunization accomplish? What is the importance of routine ongoing communicable disease surveillance? What are the essentials of Travel Medicine? How can public health officials provide useful information to a concerned citizenry by intelligent cooperation with the media? How can immunization programs and other programs for infectious disease control be kept current with the help of expert advisory committees? What are the best resources available to the public health practitioner in the area of infectious disease control? Armed with the essentials, the practitioner will have the tools to approach communicable disease problems in an orderly and rational way even in an atmosphere of public and professional ignorance and apprehension.  相似文献   
47.
Putative role of 67 kDa elastin-laminin receptor in tumor invasion   总被引:5,自引:0,他引:5  
Cellular regulatory mechanisms normally maintain a delicate balance between cell proliferation, quiescence and death. The imbalance between these functions resulting from molecular intracellular changes is a key factor in tumorigenesis. Tumor cells detaching from the primary tumor possess a propension for invasion and metastasis formation. These tumor cells can attach, migrate, proliferate and grow in host tissue. The surrounding extracellular matrix (ECM) modulates these functions. It is now widely accepted that cell-matrix interactions play an important role in these processes. Most investigators concentrated their attention on the role of integrins in the above processes. There are, however, only scant data on the role of elastin and its receptors in tumor invasion. Nevertheless, experimental evidence indicates that the 67 kDa elastin-laminin receptor (ELR) subunit plays an important role in tumor invasion by mediating essential tumor cell functions leading to metastases. In this review we will concentrate on the putative role of the 67 kDa ELR subunit in tumor invasion.  相似文献   
48.
Melatonin improves sleep quality of patients with chronic schizophrenia   总被引:3,自引:0,他引:3  
BACKGROUND: Accumulating evidence indicates decreased melatonin levels in patients with schizophrenia. Insomnia, mainly difficulty in falling asleep at night, is commonly reported in this population. Association of insomnia with low or abnormal melatonin rhythms has been repeatedly documented. Melatonin is an endogenous sleep promoter in humans. We hypothesized that insomnia in patients with schizophrenia may be partially due to diminished melatonin output. In this study, we measured melatonin output in patients with chronic schizophrenia and assessed the effects of melatonin replacement on their sleep quality. METHOD: In a randomized, double-blind, cross-over, clinically based trial, 19 patients with DSM-IV schizophrenia who were treated with the normal treatment regimen were given melatonin (2 mg, controlled release) or placebo for 2 treatment periods of 3 weeks each with 1 week washout between treatment periods (7 weeks total). For measuring endogenous melatonin production, urine was collected from each patient every 3 hours between 9:00 p.m. and 9:00 a.m. Actigraphy was performed for 3 consecutive nights at the end of each period. Activity- and rest-derived sleep parameters were compared for the whole population with treatment arm as the intervening variable. A separate analysis was performed for patients subgrouped into high versus low sleep efficiency. RESULTS: All patients had low melatonin output. Melatonin replacement significantly improved rest-derived sleep efficiency compared with placebo (83.5% vs. 78.2%, p = .038) in this population. Improvement of sleep efficiency was significantly greater (p < .0014) in low-efficiency (80% vs. 67%) than high-efficiency sleepers (88% vs. 90%). In addition, during melatonin therapy, tendencies toward shortened sleep latency (by 40 minutes, p < .056) and increased sleep duration (by 45 minutes, p < .078) were observed in low- but not high-efficiency sleepers. CONCLUSION: Melatonin improves sleep efficiency in patients with schizophrenia whose sleep quality is low.  相似文献   
49.
OBJECTIVE: The average per person direct cost of illness of cardiorespiratory disease episodes was estimated based on a prospective study of emergency department visits. METHODS: Economic modelling of health care costs using prospectively collected resource utilization data (9/1/94 to 8/31/95) from hospital emergency department visitors assigned a diagnosis of asthma, chronic obstructive pulmonary disease (COPD), respiratory infections or cardiac conditions. RESULTS: The total direct costs (1997 CDN$) [95% C.I.] per patient were $1,043.55 [$922.65, $1,164.47] for asthma, $1,690.11 [$1,276.92, $2,103.30] for COPD, $676.50 [$574.46, $778.54] for respiratory infections, and $3,318.74 [$2,937.72, $3,699.76] for cardiac conditions. CONCLUSIONS: This study showed that on average, patients diagnosed with a cardiac condition had the highest total direct cost. Hospitalization cost was the largest component of costs for all diagnoses except asthma, for which medications were the single largest component of direct costs.  相似文献   
50.
Rocuronium in the myasthenic patient   总被引:1,自引:0,他引:1  
A. Baraka    S. Haroun-Bizri  N. Kawas    A-M. Hajjar    N. Kawkabani 《Anaesthesia》1995,50(11):1007-1007
  相似文献   
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