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21.
G Barnett 《Molecular pharmacology》1986,29(4):378-382
Metal cation binding to N7 of guanine (G) and the resulting altered interaction with cytosine (C) were investigated by ab initio quantum chemical calculations for the ions Li+, Na+, B+, Be2+, and Mg2+. It was found that the CG H-bonding interaction becomes more stable and the stacking interaction less stable as the charge density for the ion (ion charge/ionic radius) increases. From this observation a hypothesis is presented for a structure-activity relationship, which is supported by in vivo animal data, that may permit the design of less toxic analogues of the antitumor agent cisplatin. 相似文献
22.
Physical activity is an important, but often underused, therapeutic strategy within diabetes care. To date, little is known about the best way to promote physical activity in diabetes care. Physical activity consultation is an intervention designed to promote physical activity behaviour change. This article provides guidelines on how to conduct a physical activity consultation with people who have Type 2 diabetes, and reviews the evidence surrounding the effectiveness of this intervention in this population. The trans-theoretical model is the underlying theory of behaviour change for the physical activity consultation intervention. The review identifies research which supports the use of this model for understanding physical activity behaviour in people with Type 2 diabetes. The review outlines a number of modifiable variables associated with physical activity behaviour change in this population. How each of these variables is addressed within the guidelines for conducting a physical activity consultation is identified. Finally, limited but consistent research highlights the effectiveness of physical activity consultation for promoting physical activity in people with Type 2 diabetes. 相似文献
23.
Sean J. Barnett M.S. M.D. Christopher Stanley B.S. Melanie Hanlon R.N. C.N.P. Robert Acton M.D. Daniel A. Saltzman M.D. Ph.D. Sayeed Ikramuddin M.D. Henry Buchwald M.D. Ph.D. 《Surgery for obesity and related diseases》2005,1(4):1609-398
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy. 相似文献
24.
R K Conlee D W Barnett K P Kelly D H Han 《Metabolism: clinical and experimental》1991,40(10):1043-1047
Cocaine and exercise are both known as stressors, but little is known about the combined effects of these two treatments. In this study, rats under the influence of cocaine (12.5 mg/kg, intraperitoneally [IP]) or saline were exposed to a variety of resting conditions, as well as exercise (running, 26 m/min, 10% grade, for 30 minutes), to evaluate the amount of stress imposed by these conditions as determined by the changes in the plasma concentrations of corticosterone (C) and catecholamines (norepinephrine [NE], epinephrine [E], dopamine [DA]). After injection of saline, resting near the operating treadmill for 30 minutes caused the concentration of C to increase from 0.07 +/- 0.03 to 0.30 +/- 0.05 microgram/mL (P less than .05), compared to the increase to only 0.15 +/- 0.04 micrograms/mL after resting in a cage. This increase due to proximity to the treadmill subsided after 50 minutes. After cocaine, the 30-minute resting values were 0.70 +/- 0.15 (treadmill) and 0.55 +/- 0.13 (cage) (P less than .05), and did not subside after 50 minutes. Cocaine also increased levels of E, NE, and DA above those in saline under all rest conditions. With exercise, the value for C in saline increased to 0.61 +/- 0.18, but, in cocaine, the value went to 0.93 +/- 0.05 (P less than .05). The concentrations of E (946 +/- 74 v 603 +/- 101 pg/mL, cocaine v saline) and NE (1,027 +/- 102 v 440 +/- 153, cocaine v saline) during exercise also were exaggerated by cocaine treatment (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
25.
Pamela E. B. Rodgers-Johnson Frederick W. Hickling Aggrey Irons Bruce K. Johnson Maureen Irons-Morgan Gary A. Stone Clarence J. Gibbs 《Journal of molecular neuroscience : MN》1996,28(1-3):237-243
Reports of an 18-fold higher incidence of schizophrenia among second-generation Afro-Caribbeans, and especially Jamaican migrants
in the United Kingdom were soon called “an epidemic of schizophrenia,” with the inference that a novel virus, likely to be
perinatally transmitted, was a possible etiological agent. This intriguing observation led us to explore a possible link with
human T-cell lymphotropic virus type one (HTLV-I), because it is a virus that is endemic in the Caribbean Islands, is perinatally
transmitted, known to be neuropathogenic, and the cause of a chronic myelopathy (tropical spastic paraparesis/ HTLV-I associated
myelopathy). We therefore examined inpatients at the Bellevue Mental Hospital, Kingston, Jamaica and did standard serological
tests for retroviruses HTLV-I and HTLV-II and HIV-I and HIV-II on 201 inpatients who fulfilled ICD-9 and DSM III-R criteria
for schizophrenia. Our results produced important negative data, since the seropositivity rates for HTLV-I, the most likely
pathogen, were no greater than the seropositivity range for HTLV-I carriers in this island population, indicating that HTLV-I
and the other retroviruses tested do not play a primary etiological role in Jamaican schizophrenics. 相似文献
26.
J. Craig Barnett Robert J. Freedman Robert C. Touchon Mark R. Mesner 《Catheterization and cardiovascular interventions》1993,28(3):206-213
Synchronized coronary venous retroperfusion of autologous arterial blood was offered to patients referred for medically refractory unstable angina or evolving myocardial infarction with contraindications to thrombolytic therapy. Primary endpoints of angina, ST segment deviation, and two-dimensional echocardiographic systolic wall motion were followed to determine the efficacy of retroperfusion in patients prior to and then during angioplasty, surgical intervention, or pharmacological management, as the clinical picture warranted. Over a 12 month period, 21 patients were referred and 15 received retroperfusion. All experienced full relief of angina (p = 0·008). ST segment deviations and systolic wall motion of ischemic zones were observed to improve (p = 0·06 ST changes; p = 0·0001 wall motion changes) with synchronized retrograde perfusion. During attempts to remove patients from retroperfusion, statistically significant (p < 0·01) reproducible changes in these same endpoints were documented. Retroperfusion appears to improve acute myocardial ischemia. This technique functions well in the intensive care unit environment with only fluoroscopy as technical imaging support. 相似文献
27.
Fungal infections in cancer patients: An international autopsy survey 总被引:33,自引:0,他引:33
G. Bodey B. Bueltmann W. Duguid D. Gibbs H. Hanak M. Hotchi G. Mall P. Martino F. Meunier S. Milliken S. Naoe M. Okudaira D. Scevola J. van't Wout 《European journal of clinical microbiology & infectious diseases》1992,11(2):99-109
In an attempt to estimate the frequency of fungal infections among cancer patients, a survey of autopsy examinations was conducted in multiple institutions in Europe, Japan and Canada. Fungal infections were identified most often in leukemic patients and transplant recipients (25 % each). Fifty-eight percent of fungal infections were caused byCandida spp. and 30 % byAspergillus spp. There was considerable variability in the frequency of fungal infections in different countries. Nevertheless, this study clearly demonstrates that fungal infections represent a common complication in cancer patients, especially in patients with leukemia. 相似文献
28.
29.
E D Barnett J O Klein S I Pelton L M Luginbuhl 《The Pediatric infectious disease journal》1992,11(5):360-364
Acute otitis media (AOM) is thought to occur frequently in children infected with human immunodeficiency virus (HIV). We compared experience with AOM of 28 HIV-infected children with that of 33 children who seroreverted to HIV antibody negative status by age 18 months. The mean number of episodes/year of AOM for children who seroreverted decreased from 1.33 in the first year of life to 0.13 in the third year, whereas the mean number of episodes/year in HIV-infected children increased from 1.89 to 2.40. By age 3 years, all HIV-infected children had experienced 1 or more episodes of AOM, and 80% had experienced 6 or more, whereas 75% of children who seroreverted had experienced 1 or more episodes, and none had had 6 or more. HIV-infected children with normal T4 lymphocyte counts had a mean of 1.18 episodes of AOM in the first year of life compared with 2.35 episodes in HIV-infected children with decreased counts (P = 0.023). HIV-infected children with low counts had a nearly 3-fold increased risk of recurrent AOM (47% vs. 18%). 相似文献
30.