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51.
52.
Renal angiomyolipoma: 6 case reports and literature review 总被引:4,自引:0,他引:4
M J Malone P R Johnson B M Jumper P J Howard T B Hopkins J A Libertino 《The Journal of urology》1986,135(2):349-353
We report 6 cases of renal angiomyolipomas and review the pertinent literature concerning this disease. One case involved the rare association of tuberous sclerosis and pregnancy. Another patient without tuberous sclerosis had renal cell carcinoma and later suffered a contralateral angiomyolipoma. The pathological conditions of renal angiomyolipomas with and without tuberous sclerosis are discussed. Since angiomyolipomas present with multiple clinical similarities to renal cell carcinoma, the primary task for the clinician is to differentiate this hamartoma from carcinoma. The distinguishing characteristics and the clinical management of renal angiomyolipomas are discussed. 相似文献
53.
D. Le Elizabeth Eric R. Powers Jian-Ping Bin Howard Leong-Poi N. Craig Goodman Sanjiv Kaul 《Journal of nuclear cardiology》2007,14(2):207-214
Background The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that
TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.
Methods and Results Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and
their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with
the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not
change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve
increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine
uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a
corresponding reduction in tissue tyrosine hydroxylase activity.
Conclusions We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated
region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely
results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting
patients who would benefit from TMR.
Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled
microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by
Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health
Research and the Heart and Stroke Foundation of Canada. 相似文献
54.
Philip Peng FRCPC Manon Choiniere PhD Dominique Dion MD MSc Howard Intrater FRCPC Sandra LeFort PhD Mary Lynch FRCPC May Ong FRCPC Saifee Rashiq MSc DA FRCPC Gregg Tkachuk PhD Yves Veillette FRCPC 《Journal canadien d'anesthésie》2007,54(12):977-984
PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment. 相似文献
55.
Cora E Lewis Susan K Ewing Brent C Taylor James M Shikany Howard A Fink Kristine E Ensrud Elizabeth Barrett-Connor Steven R Cummings Eric Orwoll 《Journal of bone and mineral research》2007,22(2):211-219
We examined determinants of nonvertebral fracture in elderly men from six U.S. communities followed an average of 4.1 years. Six clinical risk factors predicted fracture risk independent of hip BMD: tricyclic antidepressant use, previous fracture, inability to complete a narrow walk trial, falls in previous year, age > or =80 years, and depressed mood. INTRODUCTION: There are few prospective studies of fracture determinants in men. We examined the associations between a comprehensive set of clinical risk factors and risk of nonspine fracture in older men and whether determinants of fracture risk were independent of total hip BMD. MATERIALS AND METHODS: A total of 5995 men > or =65 years of age were recruited from six communities in the Unites States and followed prospectively for an average of 4.1 years. Baseline assessments of demographic, lifestyle, medical history, functional status, anthropometry, and cognitive, visual, and neuromuscular function were assessed by questionnaire or examination. Triannual mailed questionnaires ascertained incident fracture; reported fractures were adjudicated by physicians using medical records and X-ray reports. Proportional hazards models were used to develop multivariable models, selecting variables and controlling for BMD. RESULTS: Of 5876 men, 4.7% (N = 275) reported an incident nonspine fracture during follow-up (11.46/1000 person-years). Tricyclic antidepressant use (hazard ratio [HR], 2.36; 95% CI, 1.25-4.46), history of fracture at or after age 50 (HR, 2.07; 95% CI, 1.62-2.65), inability to complete a narrow walk trial (HR, 1.70; 95% CI, 1.23-2.34), falls in previous year (HR, 1.59; 95% CI, 1.23-2.05), age > or =80 years (HR, 1.33; 95% CI, 1.01-1.76), depressed mood (HR, 1.72; 95% CI, 1.00-2.95), and decreased total hip BMD (HR, 1.53; 95% CI, 1.34-1.74) were independently related to increased risk. Compared with having none (48.0% of men), having three or more of the clinical risk factors (4.9% of men) increased fracture risk 5-fold, independent of BMD. Having three or more risk factors and being in the lowest tertile of BMD was associated with a 15-fold greater risk than having no risk factors and being in the highest BMD tertile. CONCLUSIONS: Several clinical risk factors were independently associated with nonspine fractures in elderly men. The combination of multiple risk factors and low BMD was a very powerful indicator of fracture risk. 相似文献
56.
57.
Howard Litwin 《European journal of ageing》2007,4(2):71-82
The aim of the inquiry was to examine the social network–mortality association within a wider multivariate context that accounts
for the effects of background framing forces and psychobiological pathways. The inquiry was based upon the Berkman et al.
(2000) conceptual model of the determinants of health. Its main purpose was to identify the salient network correlates of 7-year
all cause mortality among Jewish men and women, aged 70 and over, in Israel (n = 1,811). The investigation utilized baseline data from a national household survey of older adults from 1997 that was linked
to records from the National Death Registry, updated through 2004. At the time of the study, 38% of the sample had died. Multivariate
Cox hazard regressions identified two main network-related components as predictors of survival: contact with friends, a social
network interaction variable, and attendance at a synagogue, a social engagement variable. Friendship ties are seen to uniquely
reduce mortality risk because they are based on choice in nature, and reflect a sense of personal control. Synagogue attendance
is seen to promote survival mainly through its function as a source of communal attachment and, perhaps, as a reflection of
spirituality as well. Other possibly network-related correlates of mortality were also noted in the current analysis—the receipt
of instrumental support and the state of childlessness.
The study on which this article is based was made possible by grants from the Israel Ministry of Science and Technology to
the Israel Gerontological Data Center. 相似文献
58.
Regina P Walker Howard L Levine Martin L Hopp David Greene Kenny Pang 《Otolaryngology--head and neck surgery》2006,135(4):549-554
OBJECTIVE: To evaluate the short-term safety and efficacy of palatal implants in patients with mild and moderate obstructive sleep apnea (OSA). STUDY DESIGN AND SETTING: A prospective, non-randomized study conducted at 5 clinical sites. Three polyester implants were placed in the soft palate under local anesthesia during a single-stage office procedure. Polysomnography was conducted at baseline and 90 days post-procedure. Subjective quality of life data were collected. RESULTS: Fifty-three patients were evaluated; the apnea hypopnea index (AHI) decreased from 25.0 +/- 13.9 to 22.0 +/- 14.8 events/hour (P = 0.05). The Epworth Sleepiness Scale (ESS) decreased from 11.0 +/- 5.1 to 6.9 +/- 4.5 (P < 0.001), and the snore score decreased from 7.9 +/- 2.1 to 4.0 +/- 3.0 (P < 0.001). No serious complications occurred during the study. CONCLUSION: Palatal implants can be an effective initial low morbidity treatment option for patients diagnosed with mild to moderate OSA. 相似文献
59.
60.