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1.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
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Effects of a very-low-calorie diet and physical-training regimens on body composition and resting metabolic rate in obese females 总被引:1,自引:0,他引:1
J E Donnelly N P Pronk D J Jacobsen S J Pronk J M Jakicic 《The American journal of clinical nutrition》1991,54(1):56-61
Sixty-nine obese females received 90 d of a liquid diet providing 2184 kJ/d in clinical trials. Groups were diet only (C), diet plus endurance exercise (EE), diet plus weight training (WT), or diet plus endurance exercise and weight training (EEWT). Changes in body weight, percent fat, fat weight, and fat-free mass were not different between groups. Declines in resting metabolic rate (RMR) were approximately 7% to approximately 12% of baseline values with no differences among groups. A significant increase in work capacity (approximately 16%) was shown for EEWT. Strength index showed declines of approximately 6% for C and EE and gains of approximately 3% and approximately 10% for EEWT and WT, respectively. These clinical trials did not show advantages of any exercise regimen over diet alone for weight loss, body-composition changes, or declines in RMR. Improvements in work capacity were limited and strength improved in groups that participated in strength training. 相似文献
4.
5.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献
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R Donnelly H L Elliott P A Meredith J L Reid 《Journal of cardiovascular pharmacology》1990,16(5):790-795
Eight normotensive subjects received single and multiple doses of cromakalim (1 mg) and placebo in a randomised double-blind cross-over study to examine general tolerance to cromakalim and its effects on blood pressure (BP), heart rate (HR), and pressor responses to norepinephrine (NE) and angiotensin II (AII). In a second study, 10 hypertensive patients whose BP control was unsatisfactory with atenolol 50-100 mg received additional treatment with placebo followed by cromakalim 1 mg daily for 4 weeks. Assessments were made of BP, HR, apparent hepatic blood flow and renal blood flow (RBF), pulmonary function, and the pharmacokinetics of atenolol. Cromakalim was generally well tolerated in both normotensive and hypertensive subjects. In the normotensive group, cromakalim produced a reflex increase in HR without any detectable decrease in BP: average (placebo-subtracted) increases in HR at 4 h were 16 beats/min with subjects in an erect position after the single dose and 14 beats/min after 7 days. Cromakalim had no effect on pressor responses to NE and AII. Addition of cromakalim to atenolol was associated with modest further reductions in BP between 0.5 and 3 h after drug administration, with maximal reductions of 21/14 mm Hg (subjects in supine position) 2 h after the first dose. Cromakalim had no effect on apparent liver blood flow and RBF, pulmonary function, and the steady-state pharmacokinetics of atenolol. Single and multiple 1-mg doses of cromakalim are well tolerated but are associated with only modest vasodilator activity. 相似文献
8.
9.
M. Donnelly O. Owonikoko N. Khan W. J. Gaine 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(2):179-180
We report a case of acromio-clavicular joint septic arthritis, a very rare complication of an innocuous finger injury. 相似文献
10.