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21.
The MMPIs of 104 cocaine abusers in treatment were subjected to a hierarchical cluster analysis and two basic profile types emerged. Type I consisted of a spike on Pd and a subspike on Hyp, reflecting a rebellious, acting out character-disordered style with narcissistic traits. Type II consisted of a high-ranging, floating profile consisting of marked elevations on F, Sc, Dep, Pt, Pd, and Pa, reflecting a psychiatric patient who concurrently abused cocaine. These findings were contrasted to other MMPI typological studies, and the similarities and differences were discussed. 相似文献
22.
Dr. Andrew G. Bostom M.D. Dr. Anne L. Hume Pharm.D. Dr. Charles B. Eaton M.D. Dr. Joseph P. Laurino Ph.D. Ms. Lisa R. Yanek B.A. Ms. Mary S. Regan B.S. Mr. William H. McQuade M.P.H. Dr. Wendy Y. Craig Ph.D. Ms. Gayle Perrone M.B.A. Dr. Paul F. Jacques Sc.D. 《Pharmacotherapy》1995,15(4):458-464
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD. 相似文献
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24.
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
25.
Optimal timing of a single dose of zoledronic acid to increase strength in rat fracture repair. 总被引:4,自引:0,他引:4
Negin Amanat Michelle McDonald Craig Godfrey Lynne Bilston David Little 《Journal of bone and mineral research》2007,22(6):867-876
We hypothesized that ZA treatment would bolster fracture repair. In a rat model for closed fracture healing, a single dose of ZA at 0, 1, or 2 wk after fracture significantly increased BMC and strength of the healed fracture. Delaying the dose (1 or 2 wk after fracture) displayed superior results compared with dosing at the time of fracture. INTRODUCTION: Bisphosphonates are known to increase bone strength and thus the resistance to fracture by decreasing osteoclastic bone resorption. These properties may enable bisphosphonates to also increase the strength of fracture repair. Zoledronic acid (ZA) is a potent bisphosphonate with a high affinity for bone mineral, allowing bolus intravenous dosing in a range of indications. In this study, we examined the application of bolus dose ZA in endochondral fracture repair. MATERIALS AND METHODS: Carbon-14 labeled ZA was used in a closed rat fracture model. Rats were divided into five treatment groups (n = 25 per group): saline control, local ZA (0.01 mg/kg), and three systemic bolus ZA groups (0.1 mg/kg) with different administration times: at fracture, 1 wk after fracture, and 2 wk after fracture. Rats were killed 6 wk postoperatively. Postmortem analyses included radiography, QCT, microCT, biomechanical testing, scintillation counting, autoradiography, and histology. RESULTS: Single-dose systemic ZA administration significantly increased callus volume, callus BMC, and mechanical strength. Perioperative treatment increased mechanical strength by 30% compared with controls (p < 0.05). Administering the systemic dose at 1 or 2 wk after fracture further increased mechanical strength compared with controls by 44% and 50%, respectively (p < 0.05). No significant differences in mechanical parameters were seen with local injection at the dose studied. Autoradiographic analysis indicated that ZA binds significantly to bone that is present at the time of administration. ZA quantification indicated that delayed administration significantly increased the uptake efficiency in the callus. Histological and microCT analysis showed that ZA treated calluses had a distinctive internal structure consisting of an intricate network of retained trabecular bone. CONCLUSIONS: The timing of a single systemic dose of ZA plays an important role in the modulation of callus properties in this rat fracture model; delaying the single dose produces a larger and stronger callus. 相似文献
26.
D Craig Willcox Bradley J Willcox Sanae Shimajiri Sayuri Kurechi Makoto Suzuki 《The American journal of geriatric psychiatry》2007,15(3):252-256
OBJECTIVE: This study retrospectively explored the late-life functional status of Okinawan centenarians. METHODS: Activities of daily living were measured retrospectively at five time points (10, 5, 3, and 1 year prior and present) for 22 centenarians in relation to seven physical, two sensory, and two cognitive functions using the Inoue Index. RESULTS: In all, 82% of individuals were still functioning independently at a mean age of 92 years and almost two-thirds were still functioning independently at a mean age of 97 years. CONCLUSION: Preliminary analyses suggest high functional status in Okinawan centenarians throughout their 90 s. The genetic and environmental factors contributing to this successful aging phenomenon deserve further investigation. 相似文献
27.
Aim: To examine the evidence of benefit in initiating immediate chemotherapy in patients with newly diagnosed asymptomatic metastatic incurable cancer, compared with delaying chemotherapy until symptomatic progression. Methods: Through an extensive review of published reports, we examined the biological, clinical, psychological and ethical background of the issue and reported on the available clinical trial evidence in a variety of tumor types. Results: Only a limited number of clinical trials have directly examined the role of immediate versus delayed chemotherapy in patients with incurable asymptomatic metastatic cancer. Small studies in mesothelioma, colorectal cancer, breast cancer, myeloma, and low‐grade lymphoma suggest no survival benefit for the immediate initiation of chemotherapy. However, there was no evidence in other tumor types. Conclusion: The appropriate timing of chemotherapy initiation in an asymptomatic patient with metastatic cancer remains a substantial question in oncology. Many factors are likely to impact on the decision. However, little if any evidence demonstrates a clear advantage in the immediate initiation of chemotherapy in this setting. 相似文献
28.
29.
30.
Delayed osteotomy but not fracture healing in pediatric osteogenesis imperfecta patients receiving pamidronate. 总被引:2,自引:0,他引:2
Craig Fj Munns Frank Rauch Leonid Zeitlin Fran?ois Fassier Francis H Glorieux 《Journal of bone and mineral research》2004,19(11):1779-1786
This study evaluated factors influencing fracture (n = 197) and osteotomy (n = 200) healing in children with moderate to severe OI. Pamidronate treatment was associated with delayed healing after osteotomy, but not after fracture. The data suggest that both pamidronate and mechanical factors influence bone healing in this cohort. INTRODUCTION: Intravenous pamidronate is widely used to treat children with moderate to severe osteogenesis imperfecta (OI). However, the effect of this treatment on bone healing is not well characterized. We therefore retrospectively analyzed the healing of lower limb fractures and osteotomies in children with moderate to severe OI, both before and after the start of pamidronate treatment. MATERIALS AND METHODS: Bone healing was evaluated on standard radiographs after 197 lower limb fractures (132 femur and 65 tibia) in 82 patients (age at fracture, 0.0-19.9 years) and 200 intramedullary rodding procedures in 79 patients (age at surgery, 1.2-19.8 years). Delayed healing was diagnosed when a fracture or osteotomy line was at least partially visible 12 months after the event. RESULTS: Delayed fracture healing was observed more frequently during than before pamidronate treatment. However, the effect of pamidronate was no longer significant when age differences were taken into account (odds ratio [OR], 1.76; 95% CI, 0.61-5.10). Better mobility status was a strong independent predictor of delayed healing after fractures that occurred during pamidronate treatment. After osteotomies, delayed healing was more frequent when pamidronate had been started before surgery (OR, 7.29; 95% CI, 2.62-20.3), and this effect persisted after adjustment for multiple confounders. During pamidronate treatment, older age (OR per year of age, 1.25; 95% CI, 1.06-1.47) and osteotomy of the tibia (OR, 3.51; 95% CI, 1.57-7.82) were independent predictors of delayed healing. CONCLUSIONS: This study suggests that pamidronate therapy is associated with delayed healing of osteotomy sites after intramedullary rodding procedures. Better mobility status, but not pamidronate treatment, seems to be predictive of delayed healing after fractures. 相似文献