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61.
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
62.
Angina pectoris and coronary artery disease in severe isolated valvular aortic stenosis 总被引:1,自引:0,他引:1
Silaruks S Clark D Thinkhamrop B Sia B Buxton B Tonkin A 《Heart, lung & circulation》2001,10(1):14-23
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
63.
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
64.
65.
NEED—The effect of dimensional variability of sheet thickness (tolerance) and tool misalignment is poorly understood for the clinching process. Finite element analysis (FEA) is valuable but requires a lot of and is difficult to verify in this situation due to the asymmetrical geometry and nonlinear plasticity. OBJECTIVE—The objective of this work was to determine the effect of thickness tolerance, tool misalignment and sheet placement (top vs. bottom) in the clinching process, by use of analogue modelling with plasticine. METHOD—Experiments used a scaled-up punch and die, with plasticine as the analogue. Thickness tolerances were represented by sheet thicknesses of 11 and 7 mm, 12 and 8 mm, 8 and 12 mm and 13 and 9 mm for upper and lower sheets, respectively. Two types of lubricant were tested between sheets: glycerine and silicone oil. Angular variability was also introduced. Measured parameters were interlock (also called undercut) and neck thickness. Analogue results for deformation were compared with microscopy of metal clinching. FINDINGS—The results reveal that the multiscale analogue model is an efficient tool for studying the effect of dimensional deviation on a clinch joint. Thickness tolerance showed a critical relationship with interlock, namely a reduction to about half that of the nominal, for both maximum and least material conditions. Increased angular misalignment also reduced the interlock. Compared with glycerine, silicone oil tests showed reduced interlock, possibly the result of a lower coefficient of friction. ORIGINALITY—This work demonstrates the usefulness of analogue modelling for exploring process variability in clinching. The results also show that significant effects for sheet placement are ductility, lubricant (friction), thickness of samples and tool misalignment. 相似文献
66.
World Workshop on Oral Medicine VI: a systematic review of medication‐induced salivary gland dysfunction
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A Villa A Wolff N Narayana C Dawes DJ Aframian AM Lynge Pedersen A Vissink A Aliko YW Sia RK Joshi R McGowan SB Jensen AR Kerr J Ekström G Proctor 《Oral diseases》2016,22(5):365-382
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
67.
Michael Heidelberger Richard H. P. Sia Forrest E. Kendall 《The Journal of experimental medicine》1930,52(4):477-483
1. A rapid and simple method is given for the approximate determination of the specifically precipitable protein in Type I antipneumococcus sera. 2. It is shown that a close parallel exists between the specifically precipitable protein and the number of mouse protection units in a wide variety of Type I antipneumococcus sera. 3. Owing to the consistent results obtained and the rapidity, simplicity, and economy of the method, its use is proposed instead of the mouse protection test as a basis for the titration of standard sera and the comparison of others with a standard. 4. A method is given for conveniently preparing highly purified specific polysaccharide of Type I pneumococcus. 相似文献
68.
Richard H. P. Sia Oswald H. Robertson Shutai T. Woo 《The Journal of experimental medicine》1928,48(4):513-532
Employing a method devised for the investigation of natural immunity and experimental pneumococcus infection, a study has been made of the serum immune changes occurring during the course of lobar pneumonia due to Pneumococcus Types I and II and Group IV, in man. It was found that at the time of crisis or lysis the blood serum acquired constantly the property of promoting pneumococcus killing to a relatively marked degree. Other evidences of antipneumococcus reaction—mouse protection, opsonins, and agglutinins—were also demonstrable in the blood at this time. These immune changes appeared in the majority of cases at the beginning of recovery and failed to occur when the disease terminated fatally. The fact that these observations in human cases are practically identical with previous findings in the experimental disease in cats, enhances considerably the significance of the development of serum immune bodies at the time of crisis since in the experimental animal it was possible to show that the acquisition of passive immunity was associated with greatly increased antipneumococcus resistance. 相似文献
69.
Production of immunogenic HIV-1 viruslike particles in stably engineered monkey cell lines. 总被引:3,自引:0,他引:3
J R Haynes S X Cao B Rovinski C Sia O James G A Dekaban M H Klein 《AIDS research and human retroviruses》1991,7(1):17-27
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
70.