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81.
Orbitofrontal cholesterol granuloma is a rare entity that has a predilection for men in their fourth or fifth decade and occurs almost exclusively within the frontal bone overlying the lacrimal fossa. Surgery by drainage and curettage is virtually curative in all cases and recurrence is very rare. We describe the case of a 77-year-old man with recurrent orbitofrontal cholesterol granuloma 11 years after surgery, presumably due to subtotal curettage. The potential use of an endoscope to aid complete removal of lesion is discussed.  相似文献   
82.
BACKGROUND: Angina pectoris has long been recognised as one of the principal symptoms of severe aortic valve stenosis (AS), even in patients without significant coronary artery disease (CAD). However, controversy exists concerning the prevalence of angina pectoris and associated CAD in such patients. OBJECTIVE: To determine the prevalence of CAD detectable by angiography and its relation to angina pectoris and coronary risk factors in patients with severe AS. PATIENTS AND METHODS: All patients with symptomatic AS who had undergone aortic valve replacement and preoperative cardiac catheterisation at the Austin and Repatriation Medical Centre between 1 January 1986 and 31 May 1996 were retrospectively analysed. Those patients with multiple valve disease, aortic regurgitation of grade 2 or more in severity, or who had had prior coronary artery or valve surgery were excluded from this analysis. RESULTS: A total of 328 consecutive patients with severe AS (242 men and 86 women; mean age 72 years, range 39-84 years) were studied. Significant CAD (reduction in luminal diameter > or = 50%) was found in 162 patients (49.4%). Typical angina was present in 74.7% of these 162 patients but it was also found in 44.6% of the 166 patients without obstructive CAD. Of the patients without angina (n = 133), 30.8% had significant CAD. By multivariate logistic regression, we have identified seven significant predictors for CAD among severe AS patients. Five factors increased risk. Expressed as odds ratio with 95% confidence interval, these included: (i) age in years (1.07; 1.04-1.11, P = 0.001); (ii) male gender (2.09; 1.14-3.80, P = 0.016); (iii) angina pectoris (3.19; 1.89-5.37, P < 0.001); (iv) history of myocardial infarction (2.87; 1.38-5.97, P = 0.005); and (v) peripheral vascular disease (2.28; 1.28-4.05, P = 0.005). Factors associated with decreased likelihood of CAD were serum high density lipoprotein (HDL) cholesterol (0.58; 0.34-0.71, P = 0.002) and peak systolic gradient across the aortic valve (0.97; 0.95-0.99, P = 0.0113). CONCLUSION: Coronary arteriography can probably be omitted for a patient with severe AS if that patient has no symptoms of angina and has no risk factors known to increase its incidence.  相似文献   
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The aim of this paper was to perform a systematic review of the pathogenesis of medication‐induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α‐and β‐adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.  相似文献   
84.
A. T. H. Sia  H. S. Tan  B. L. Sng 《Anaesthesia》2012,67(12):1348-1355
Hypotension occurs in most caesarean sections under spinal anaesthesia, necessitating vasopressor administration. However, the optimal dosing regimen remains unclear. We have developed a novel vasopressor delivery system that automatically administers phenylephrine or ephedrine based on continuous non‐invasive blood pressure monitoring. This prospective cohort study recruited 55 healthy women under standardised spinal anaesthesia with 2.2 ml hyperbaric bupivacaine 0.5%, 15 μg fentanyl and 100 μg morphine. A 50‐μg phenylephrine bolus was given at 1‐min intervals when systolic blood pressure fell below 90% of baseline, and a 4‐mg ephedrine bolus was given when hypotension developed with bradycardia (heart rate <60 beats.min?1). Systolic blood pressure was within 20% of baseline in 88% of all measurements. Six patients (11%) had one or more measurements above 120% of baseline (1% of all measurements), whereas 36 (65%) had at least one reading below 80% of baseline (11% of total measurements). The system maintained systolic blood pressure at a mean (SD) of ?9.1 (7.0)% below baseline, with 5.4 (2.5)% fluctuation. Two patients (4%) experienced pre‐delivery nausea. All 5‐min Apgar scores were 9.  相似文献   
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86.
A proviral fragment from human immunodeficiency virus type 1 (HIV-1) (LAV-1BRU) containing only protein-coding information, was expressed in COS cells using constitutive promoters in transient and stable transfection experiments. The presence of viruslike particles in cell supernatants was verified by Western blot analysis, density gradient centrifugation, and electron microscopy. Transfection of Vero cells with a similar construct employing the human metallothionein promoter led to the isolation of stable cell lines exhibiting inducible viruslike particle expression in response to cadmium chloride treatment. Induction ratios for viruslike particle expression were in excess of 1000-fold with production levels of p24 core antigen as high as 0.6 mg/L per 24 h. HIV-1 viruslike particles were immunogenic in mice, leading to strong envelope and core-specific humoral responses after two immunizations. The development of stable cell lines expressing significant quantities of HIV-1 viruslike particles offers an alternative to the use of live virus vectors for the production and evaluation of particle-based AIDS vaccines.  相似文献   
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Guidelines for international collaborative research   总被引:2,自引:1,他引:1  
OBJECTIVE: As the global village becomes a reality, there is an increasing need to conduct international collaborative studies in family practice. A workshop at the WONCA meeting in Hong Kong used international attendees to produce a set of guidelines for international research. METHODS: At the workshop four completed international projects, each using a different strategy, were presented so that common themes might become apparent. The themes were then discussed and guidelines emerged from the process. RESULTS: Seven guidelines emerged for consideration before embarking on an international collaborative research project in family medicine. The guidelines deal with the characteristics of the research question and the importance of communication. The need for simple, brief methods of data collection, funding and pilot testing were identified. CONCLUSION: The question must be relevant to all participants to maintain interest and measurement tools must be validated to understand the impact of cultural differences in understanding.   相似文献   
90.
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