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Falls in older people can be caused by underlying cardiovascular disorders, either because of balance instability in persons with background gait and balance disorders, or because of amnesia for loss of consciousness during unwitnessed syncope. Pertinent investigations include a detailed history, 12-lead electrocardiography, lying and standing blood pressure, carotid sinus massage (CSM), head-up tilt, cardiac electrophysiological tests, and ambulatory blood pressure and heart rate monitoring, which includes external and internal cardiac monitoring. The presence of structural heart disease predicts an underlying cardiac cause. Conversely, the absence of either indicates that neurally mediated etiology is likely. CSM and tilt-table testing should be considered in patients with unexplained and recurrent falls. Holter monitoring over 24 hours has a low diagnostic yield. Early use of an implantable loop recorder may be more cost-effective. A dedicated investigation unit increases the likelihood of achieving positive diagnoses and significantly reduces hospital stay and health expenditure. 相似文献
133.
Alan H. Lockwood Kathryn E. Peek Marc Berridge Linda Bogue Eddy Yap 《Metabolic brain disease》1987,2(1):47-60
We developed a double-isotope autoradiographic method for the simultaneous measurement of the local cerebral metabolic rate for glucose (1CMRG) and index of regional acid-base status (rABI) in single brain slices using [2-14C]deoxy-D-glucose (DG) and 5,5-dimethyl-[2-14C]oxazolidine-2,4, dione (DMO). After iv isotope administration, paper chromatography separates plasma DMO from DG activity using a methanol-methylene chloride solvent system. Initial tissue autoradiograms depict regional DMO plus DG and DG metabolite distribution. After 14 days in a well-ventilated hood, 97.5 ±0.5% of all DMO is lost from tissue sections by sublimation, and a second autoradiogram depicts DG plus DG metabolite distribution. Retention of brain lipids does not alter beta-particle self-absorption, avoiding problems associated with isotope extraction with solvents. Autoradiograms are digitized and converted to isotope-content images. The second autoradiogram is used for lCMRG computation. After subtracting the second regional isotope-content value from the first, the DMO content is obtained and used to compute rABI. Application of this method to normal animals yields expected values for lCMRG and rABI. This method is amenable to whole-slice digitization and creation of functional images of lCMRG and ABI followed by pixel-by-pixel correlations of the two variables, making this a potentially valuable tool for the investigation of the relationships between glucose metabolism and brain acid-base balance. 相似文献
134.
Association of Mycoplasma genitalium with nongonococcal urethritis in heterosexual men 总被引:10,自引:0,他引:10
Totten PA Schwartz MA Sjöström KE Kenny GE Handsfield HH Weiss JB Whittington WL 《The Journal of infectious diseases》2001,183(2):269-276
Chlamydia trachomatis and Neisseria gonorrhoeae are universally acknowledged as urethral pathogens, yet the etiology in the majority of cases of urethritis is unclear. Our case-control study assessed the association of Mycoplasma genitalium, Ureaplasma urealyticum, and other potential pathogens with acute nongonococcal urethritis (NGU) in heterosexual men presenting to an urban sexually transmitted diseases clinic. M. genitalium was detected in 27 (22%) of 121 NGU case patients and in 5 (4%) of 117 control subjects (P<.01). Although C. trachomatis was detected in 36 (30%) of 121 NGU case patients and in 4 (3%) of 117 control subjects (P<.01), only 3 men with NGU were infected with both C. trachomatis and M. genitalium. U. urealyticum was not associated with NGU. By multivariate analyses, controlling for age, race, history of prior urethritis, and chlamydial infection, M. genitalium was associated with a 6.5-fold increased risk of urethritis (95% confidence interval, 2.1-19.5), which supports a role of this organism in the etiology of NGU. 相似文献
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INTRODUCTION: Reveal is a patient activated implantable loop recorder device with an 18 month battery life now available to assist in the diagnosis of suspected syncope or arrhythmias. We present our experience using this device in older subjects referred to a dedicated falls and syncope clinic in whom usual clinical assessment had not satisfactorily identified an attributable diagnosis but where we still suspected a cardiovascular cause for syncope or falls. METHODS AND RESULTS: during the past 3 years 15 subjects (mean age 73 years, range 61-89 years) had Reveal implanted for symptoms of syncope alone (n=6; 40%) and unexplained falls (n=3; 20%) or symptoms of syncope and unexplained falls (n=6; 40%). Symptom duration was long (mean 48 months; range 4-200 months). Subjects had experienced significant morbidity, 6 subjects (40%) required A&E attendance or hospital admission and 4 (27%) experienced a fracture. Despite extensive and repeated investigations, which included 12-lead ECG, echocardiogram, 24-h ambulatory heart rate monitor, 24-h ambulatory blood pressure monitor, orthostatic blood pressure measurement, supine and erect carotid sinus massage, electroencephalogram, and passive and GTN head up tilt testing, the attributable diagnosis remained unexplained. Of the 15 subjects, 7 have activated the device at 4 (range 0-14) months after implantation. Bradycardia was identified in 3 and ventricular tachycardia in 1 subject. Two subjects did not activate the device during the 18 months it was in-situ. Four people had problems with device activation. This is comparable to rates noted using Reveal in younger subjects. CONCLUSION: Reveal offers additional diagnostic yield in complex elderly subjects with suspected cardiovascular causes of syncope or unexplained falls which have not been previously satisfactorily diagnosed despite extensive investigations. 相似文献
138.
Noor H. A. Suaini Evelyn Xiu-Ling Loo Rachel L. Peters Gaik Chin Yap Katrina J. Allen Hugo Van Bever David J. Martino Anne Eng Neo Goh Shyamali C. Dharmage Marjorelee T. Colega Mary Foong Fong Chong Anne-Louise Ponsonby Kok Hian Tan Mimi L. K. Tang Keith M. Godfrey Bee Wah Lee Lynette Pei-Chi Shek Jennifer J. Koplin Elizabeth Huiwen Tham 《Allergy》2021,76(10):3171-3182
139.
S. Beaumont N. Bhatia L. McDowell T. Fua M. McCullough A. Celentano T. Yap 《The British journal of oral & maxillofacial surgery》2021,59(5):511-523
This systematic review aimed to examine whether the incidence of osteonecrosis differed between patients who have dental extractions before or after radiotherapy (RT). The reported incidence of osteoradionecrosis (ORN) of the jaws following RT to the head and neck varies widely in the literature. Currently, for patients with head and neck cancer there are no universally accepted guidelines on the optimal timing of dental surgery relative to RT to minimise incident ORN. A literature review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) criteria. A search of PubMed, EMBASE, Evidence-Based Medicine, and Web of Science databases targeted literature published up to and including 10 April 2020. Two independent reviewers assessed studies for eligibility against inclusion criteria. An assessment of bias was conducted for each of the included studies and relevant data extracted. A meta-analysis was undertaken using the statistical methods described. Twenty-four of 708 studies were included. They were heterogeneous and included a wide variation of RT methods, head and neck malignancies, and comorbidities. While some concluded that the incidence of ORN was dependent on the timing of dental extractions in relation to RT, with regard to the risk of its development, others reported additional factors such as age, comorbidities, extent of surgical resection, and dose and field of radiation, as more important predictors than timing. In many there was consistent lack of detail around the timing of dental procedures in relation to the delivery of RT. From 21 studies including 36,294 patients, of whom 14,389 had extractions before RT, the pooled incidence of ORN was 5.5% (95% CI: 2.1% to 10.1%). Significant heterogeneity was found in Cochran’s Q-test (p < 0.001) and Higgins I2 = 98.0%. From 21 studies including 37,805 patients, of whom 6030 had extractions after RT, the pooled incidence of ORN was 5.3% (95% CI: 2.9% to 8.2%). Significant heterogeneity was found in Cochran’s Q-test (p < 0.001) and Higgins I2 = 80.0%. There was no statistically significant difference between these two groups (random-effects model Q=0.12, p=0.73). Large, longitudinal studies with a priori-specified methods are needed to identify, recruit, and prospectively follow patients with head and neck cancer for the onset of ORN after dental surgery. This will allow clinical guidelines to be established to assist clinicians to plan treatment when extractions are indicated in patients undergoing RT to the head and neck. 相似文献
140.
Leong Dephne Jack Xin de Souza Nurun Nisa Sultana Rehena Yap Adrian Ujin 《Clinical oral investigations》2020,24(1):465-473
Clinical Oral Investigations - Systematic review analyzing the treatment outcomes of cracked teeth that received endodontic treatment is unavailable. The purpose of this study was to examine the... 相似文献