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101.
BACKGROUND: Electron beam tomography (EBT) is a noninvasive technique that allows the study of the entire coronary artery tree during a brief imaging session without the injection of any contrast media. Atherosclerosis is identified vicariously through the visualization of coronary calcific deposits. Quantitative assessments of calcium burden, such as calcium volume scores, have been shown to be a useful means to assess treatment-related changes in the extent of atherosclerotic plaques. Historically, the elderly female population has received less medical recognition regarding the risk and severity of coronary heart disease (CHD). METHODS: In the BELLES (Beyond Endorsed Lipid Lowering with EBT Scanning) trial, the presence of asymptomatic CHD in 600 postmenopausal women will be assessed by EBT. In this 1-year, multicenter, randomized, double-blind, parallel-group study, aggressive lipid-lowering treatment will be compared with moderate lipid-lowering treatment in postmenopausal women with hypercholesterolemia. The hypothesis we will test is that aggressive lipid-lowering therapy with 80 mg/d atorvastatin can produce greater reductions in atherosclerotic plaque burden as assessed by volumetric calcium scores than a moderate treatment with 40 mg/d pravastatin. The primary outcome measure will be the percent change from baseline in total CVS determined by EBT at 12 months. CONCLUSIONS: The results of the BELLES trial will help assess the actual incidence of CHD in postmenopausal women and the relative ability of two different lipid-lowering therapies to halt its progression.  相似文献   
102.
103.
Patient satisfaction is an important outcome measure independent of other outcomes. Its measurement is important to assess the effectiveness of a programme and to gain insight into the patients'' perception of the programme. In this study conducted in a large rehabilitation centre it was found that majority of patients express satisfaction with care inspite of perceived discomfort. Various demographic factors, severity or duration of the disability or the level of rehabilitation do not influence patient satisfaction. Patients express more concern with aspects such as delay in issue of the prosthesis, or hotel component of the hospital services. Patients did not appear too concerned about the level of information provided. Patient satisfaction is an individual reaction to the overall care process and is influenced by the initial expectation level of the patient. Emotional response of the patient appears to be more important determinant of patient satisfaction than the cognitive evaluation. Periodical assessment of patient satisfaction should be an important component of any programme evaluation exercise.KEY WORDS: Amputation, Patient satisfaction, Programme evaluation, Prosthesis, Quality of care, Rehabilitation  相似文献   
104.
Two cases of epidermal cyst of the breast, a rare benign condition, were detected during a 3-year period in a mammographic screening programme, from 57 954 screening examinations. It is not uncommon for epidermal cysts to be initially misdiagnosed. The mammographic, ultrasound and histological features are presented. It is recommended that these lesions be resected because they possibly have malignant potential.  相似文献   
105.
Serial liver enzyme and bilirubin concentrations were measured in 100 patients undergoing total parenteral nutrition. Between the eighth and tenth days, serum glutamic-pyruvic transaminase levels rose to 5.4 times pretotal parenteral nutrition levels; serum glutamic-oxalacetic transaminase, 2.8 times; bilirubin, 2.3 times, and lactic dehydrogenase, 1.5 times. These elevations were transient, lasting four to ten days. Biopsies of the liver taken during maximal elevations demonstrated marked periportal fatty change. A second elevation of serum glutamic-pyruvic transaminase, serum glutamic-oxalacetic transaminase, alkaline phosphatase and lactic dehydrogenase occurred in one-third to one-half of those patients receiving total parenteral nutrition for longer than a 20 day period. These elevations were more prolonged, and no biopsies were taken. Amino acid solutions contain conversion products of tryptophan, an amino acid that is unstable in the presence of the preservative sodium bisulfite which is added to all commercially available protein solutions. Infusion of these products into rats, either alone or as part of total parenteral nutrition solutions, resulted in periportal fatty change of the livers identical to that seen in our patients receiving total parenteral nutrition. A toxic effect of tryptophan conversion products in total parenteral nutrition solutions is proposed.  相似文献   
106.
Spinocerebellar ataxia type-3 or Machado-Joseph disease (SCA3/MJD) is a member of the CAG/polyglutamine repeat disease family. In this family of disorders, a normally polymorphic CAG repeat becomes expanded, resulting in expression of an expanded polyglutamine domain in the disease gene product. Experimental models of polyglutamine disease implicate the nucleus in pathogenesis; however, the link between intranuclear expression of expanded polyglutamine and neuronal dysfunction remains unclear. Here we demonstrate that ataxin-3, the disease protein in SCA3/MJD, adopts a unique conformation when expressed within the nucleus of transfected cells. The monoclonal antibody 1C2 is known preferentially to bind expanded polyglutamine, but we find that it also binds a fragment of ataxin-3 containing a normal glutamine repeat. In addition, expression of ataxin-3 within the nucleus exposes the glutamine domain of the full-length non-pathological protein, allowing it to bind the monoclonal antibody 1C2. Fractionation and immunochemical experiments indicate that this novel conformation of intranuclear ataxin-3 is not due to proteolysis, suggesting instead that association with nuclear protein(s) alters the structure of full-length ataxin-3 which exposes the polyglutamine domain. This conformationally altered ataxin-3 is bound to the nuclear matrix. The pathological form of ataxin-3 with an expanded polyglutamine domain also associates with the nuclear matrix. These data suggest that an early event in the pathogenesis of SCA3/MJD may be an altered conformation of ataxin-3 within the nucleus that exposes the polyglutamine domain.  相似文献   
107.
Rosenbaum  RC; Johnston  GS 《Radiology》1986,160(1):91-94
The authors studied 54 patients with multisystem trauma, including blunt chest injury, using combined dynamic first-pass and electrocardiographically (ECG) gated radionuclide ventriculography (RNV) to evaluate for posttraumatic myocardial dysfunction. Twenty-six of 54 (48%) patients had abnormalities of ventricular wall motion. The ventricular dysfunction was confined to the right ventricle in 92% of cases. In general, abnormalities consisted of right ventricular dilatation and diffuse hypokinesia, although in seven cases there were localized wall-motion abnormalities. The right ventricular ejection fraction of those patients with wall-motion abnormalities was significantly lower than those with normal studies. Left ventricular ejection fraction did not differ significantly between these groups. ECG changes were not associated with the cardiac dysfunction demonstrated scintigraphically, nor was there a relationship between the number or type of extrathoracic or thoracic injuries demonstrated by RNV. Follow-up studies obtained in 15 cases showed a significant overall improvement in cardiac function by 3 weeks after injury. Combined first-pass and ECG-gated RNV is useful for the identification and follow-up of patients with posttraumatic cardiac dysfunction.  相似文献   
108.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.  相似文献   
109.
The nicotine-derived nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most potent lung carcinogens in rodents. Several epidemiologic studies indicated that the development of lung cancer in smokers is influenced by the type and amount of dietary polyunsaturated fatty acids. A high corn oil diet has been shown to increase lung tumor volume and to decrease tumor latency in rats treated with NNK. In this study, we investigated the effects of dietary polyunsaturated fatty acids in the form of corn oil or fish oil on lung proteomes in F344 rats treated with or without NNK. The fish oil diet contained 17% fish oil and 3% corn oil, and the corn oil diet contained 20% corn oil. Rats were sacrificed after 3 months, and lungs were excised. Whole lung tissue proteins were separated by two-dimensional liquid chromatography, and differentially expressed proteins were identified by trypsin digestion and tandem mass spectrometry. Apolipoprotein A-I and Clara cell 17-kDa protein were overexpressed in the lungs of rats fed corn oil diet, compared with fish oil diet. NNK further enhanced their expression in rats fed corn oil diet; this effect was not observed in animals fed fish oil diet. The results suggest that the elevated levels of apolipoprotein A-I and Clara cell 17-kDa protein may be involved in the development of NNK-induced lung cancer in rats fed a high corn oil diet. Therefore, we propose that both proteins may serve as potential biomarkers in future molecular epidemiologic and clinical chemoprevention intervention studies.  相似文献   
110.
OBJECTIVES: To develop a gas chromatographic assay for the analysis of difluoroethane, a volatile substance, in blood and to determine assay characteristics including linearity, limit of quantitation, precision, and specificity. SETTING: Referral toxicology laboratory RESULTS: Difluoroethane, a colorless, odorless, highly flammable gas used as a refrigerant blend component and aerosol propellant, may be abused via inhalation. A headspace gas chromatographic procedure for the identification and quantitation of difluoroethane in blood is presented. A methanolic stock standard prepared from pure gaseous difluoroethane was used to prepare whole blood calibrators. Quantitation of difluoroethane was performed using a six-point calibration curve and an internal standard of 1-propanol. The assay is linear from 0 to 115 mg/L including a low calibrator at 4 mg/L, the limit of quantitation. Within-run coefficients of variation at mean concentrations of 13.8 mg/L and 38.5 mg/L were 5.8% and 6.8% respectively. Between-run coefficients of variation at mean concentrations of 15.9 mg/L and 45.7 mg/L were 13.4% and 9.8% respectively. Several volatile substances were tested as potential interfering compounds with propane having a retention time identical to that of difluoroethane. CONCLUSIONS: This method requires minimal sample preparation, is rapid and reproducible, can be modified for the quantitation of other volatiles, and could be automated using an automatic sampler/injector system.  相似文献   
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