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31.
Plasma levels of ACTH were evaluated in 18 sons of alcoholics and 18 sons of nonalcoholics before and after they consumed placebo, 0.75 ml/kg of ethanol, and 1.1 ml/kg of ethanol. The analyses revealed significant changes in ACTH levels over time, an effect of ethanol on ACTH overall, and significantly lower ACTH levels in the sons of alcoholics than in the control subjects following the high-dose ethanol challenge. The data corroborate the earlier finding that sons of alcoholics have less intense responses to ethanol and are consistent with the conclusion that changes in cortisol level associated with drinking include a pituitary response as well as effects on the adrenal glands. 相似文献
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Multicoil Dixon chemical species separation with an iterative least-squares estimation method. 总被引:1,自引:0,他引:1
Scott B Reeder Zhifei Wen Huanzhou Yu Angel R Pineda Garry E Gold Michael Markl Norbert J Pelc 《Magnetic resonance in medicine》2004,51(1):35-45
This work describes a new approach to multipoint Dixon fat-water separation that is amenable to pulse sequences that require short echo time (TE) increments, such as steady-state free precession (SSFP) and fast spin-echo (FSE) imaging. Using an iterative linear least-squares method that decomposes water and fat images from source images acquired at short TE increments, images with a high signal-to-noise ratio (SNR) and uniform separation of water and fat are obtained. This algorithm extends to multicoil reconstruction with minimal additional complexity. Examples of single- and multicoil fat-water decompositions are shown from source images acquired at both 1.5T and 3.0T. Examples in the knee, ankle, pelvis, abdomen, and heart are shown, using FSE, SSFP, and spoiled gradient-echo (SPGR) pulse sequences. The algorithm was applied to systems with multiple chemical species, and an example of water-fat-silicone separation is shown. An analysis of the noise performance of this method is described, and methods to improve noise performance through multicoil acquisition and field map smoothing are discussed. 相似文献
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Mitchel A Kling Salvatore Alesci Gyorgy Csako Rene Costello David A Luckenbaugh Omer Bonne Roman Duncko Wayne C Drevets Husseini K Manji Dennis S Charney Philip W Gold Alexander Neumeister 《Neuropsychopharmacology》2007,62(4):309-313
BACKGROUND: Major depressive disorder (MDD) shows increased coronary artery disease (CAD) risk of unknown mechanism(s). MDD is more common in women than men; CAD diagnosis can be difficult in women. Elevations of the inflammatory markers C-reactive protein (CRP) and serum amyloid A (SAA) predict increased CAD risk in populations; few data on these markers exist in MDD, particularly in remitted patients. METHODS: We measured fasting am serum CRP (high sensitivity, CRP(hs)) and SAA in 18 unmedicated, remitted women with MDD (mean age 41 +/- (SD)12, body mass index (BMI) 25.2 +/- 4.1 kg/m(2)) and 18 BMI-matched healthy control subjects (age 36 +/- 10, BMI 25.3 +/- 3.8 kg/m(2)) on 2 separate occasions, > or = 6 days apart. RESULTS: Repeat SAA and CRP(hs) measurements strongly correlated across study days (SAA: r = .83, p < .001; CRP(hs): r = .94, p < .001). Both SAA (5.30 +/- 3.39 vs. 2.84 +/- 1.87 mg/L, p < .005) and CRP(hs) (3.23 +/- 3.17 vs. 1.12 +/- 1.45 mg/L; p < .01) were significantly elevated in MDD women versus controls. CONCLUSIONS: Elevated SAA and CRP(hs) in remitted, unmedicated women with MDD indicate a pro-inflammatory state unrelated to current depressive symptoms or pharmacotherapy. These findings suggest that inflammatory mechanisms may in part underlie findings of increased CAD risk in MDD. 相似文献
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M L McLaws L M Irwig P Mock G Berry J Gold 《The Medical journal of Australia》1988,149(11-12):591-595
In July 1984, the first national Australian Nosocomial Prevalence Survey collected data on 12,742 surgical patients from 265 hospitals. This sample represented 59% of public and private hospitals with 50 or more acute-care beds in Australia. The infection control officers at each hospital provided data on patients in a random sample of beds. The over-all surgical wound infection rate was 4.6%. The surgical wound infection rate was twice (5.4%) as high in public than in private (2.8%) hospitals. The infection rates were greater in larger hospitals in both the public and private sector. However, after adjusting for the other predictor factors that are noted below the infection rate did not show any particular pattern for the size of hospital. Clean surgery had a higher (4.8%) infection rate than did clean-contaminated surgery (2.9%). The infection rate for contaminated surgery was 15.0%. Men were found to have nearly twice (6.5%) the infection rate of women (3.4%). Infection rates were lowest in the 15-to-34 years' age-group and highest in those of over 55 years of age. These trends remained even after adjusting for the other risk factors for infection. The cost of surgical wound infections for all hospitals during the year of 1984 was estimated at approximately $60 million. We suggest that a concerted effort should be made to attempt to reduce the infection rate for clean surgery to 1% or less. 相似文献
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Summary In the rat, prolonged administration of the luteinizing, hormone-releasing hormone agonist buserelin (25 μg/kg body wt/day
s.c.) lowers blood estradiol, raises bone resorption, and induces osteopenia. The present study was undertaken to determine
whether withdrawal of buserelin normalizes blood estradiol, slows bone resorption, and corrects buserelin-mediated osteopenia.
Four groups of female rats with45Ca-labeled bones were studied: group 1A received 0.2 ml saline s.c. daily for 4 weeks; group 2A received 0.2 ml buserelin
s.c. daily for 4 weeks; group 1B received 0.2 ml saline s.c. daily for 8 weeks; group 2B received 0.2 ml buserelin s.c. daily
for 4 weeks followed by 0.2 ml saline s.c. daily for 4 weeks. Bone resorption was monitored by measuring urinary45Ca and hydroxyproline. The rats in groups 1A and 2A were killed after 4 weeks and those in groups 1B and 2B after 8 weeks.
The mineral contents of the femoral bones and the whole skeletons were measured. Buserelin lowered blood estradiol, elevated
urinary45Ca and urinary hydroxyproline, and lowered femur and total body calcium and45Ca in group 2A vs. 1A (P<0.05). By contrast all these measurements became similar in groups 2B and 1B. Thus, osteopenia generated by a 4-week period
of buserelin-mediated hypo-estrogenism is reversible by withdrawing buserelin for 4 weeks. Consequently, buserelin administration
and withdrawal may be used to study effects of inducing and reversing estrogen-deficiency bone loss in the rat. 相似文献
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