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931.
932.
Helena Hachul Lia R A Bittencourt Monica L Andersen Mauro A Haidar Edmund C Baracat Sergio Tufik 《International journal of gynaecology and obstetrics》2008,103(3):207-212
OBJECTIVE: To investigate the effects of estrogen and progesterone on sleep in postmenopausal women. METHOD: The 33 participants were randomly assigned to an estrogen or placebo group after undergoing clinical and hormonal assessments and a polysomnogram, and they underwent the same tests again after 12 weeks. Then, while still taking estrogen or placebo, they all received progesterone for another 12 weeks and underwent a final polysomnogram. RESULTS: Estrogen plus progesterone was more effective than estrogen alone in decreasing the prevalence of periodic limb movement (PLM) (8.1% vs 2.8%), hot flashes (14.2% vs 0%), and bruxism (11.1% vs 0%) at night, or somnolence and attention difficulty during the day. The prevalences of breathing irregularities, arousal from sleep, anxiety, and memory impairment were decreased in both groups following progesterone treatment. CONCLUSION: While not significantly affecting sleep quality, hormone therapy decreased the prevalence of arousal in both groups and that of PLM in the group treated with estrogen plus progesterone. 相似文献
933.
934.
K E Bach Knudsen B B Jensen J O Andersen I Hansen 《The British journal of nutrition》1991,65(2):233-248
The present work was undertaken to study the microbial activity in various segments of the gastrointestinal (GI) tract of pigs as influenced by the source and level of wheat and oat dietary fibre (DF). Eight experimental diets were prepared from wheat and oat fractions and studied in a series of two experiments using wheat flour as the DF-depleted control. The diets in Expt 1 were based on wheat flour and three iso-DF enriched diets comprising fractions rich in wheat aleurone, pericarp/testa or bran. In Expt 2, oat bran was added to wheat flour to achieve the same DF intake level as in Expt 1. This series included further diets based on rolled oats and rolled oats plus oat bran. The eight diets were given to thirty-two ileal-cannulated pigs, with sixteen pigs in each experiment. After a total period of 34 d (Expt 1) and 42 d (Expt 2), the pigs were slaughtered 4 h post-feeding and samples taken for adenine nucleotides (adenosine 5'-triphosphate (ATP); adenylate energy charge (AEC)), organic acids (lactic acid (LA); short chain fatty acids (SCFA)) and pH at twelve sites of the GI tract. The microbial activity as measured by the ATP concentration was low in the stomach and the cranial two-thirds of the small intestine, but tended to increase in the distal third. In the caecum a sharp rise in microbial activity was observed; the highest level was found for the diet providing most fermentable substrates. In all the diets but the rolled oats + oat bran diets, microbial activity showed a descending pattern as the digesta moved through the colon. In the large intestine source and level of residues had a marked influence on microbial activity. LA was the chief organic acid in the stomach and small intestine (10-40 mmol/l) while LA relative to SCFA was a minor component in the caecum and colon (10-20 mmol/l). The contribution of SCFA to total organic acids was reciprocal to LA, i.e. low in the stomach and small intestine (less than 20 mmol/l) and high in the caecum and colon. In the large intestine the concentration of SCFA decreased from 100-140 mmol/l in the caecum and proximal colon to 40-80 mmol/l in the distal colon. The acetic: propionic acid ratio increased from the caecum to the distal colon. With the diets based on oat alone (rolled oats; rolled oats + oat bran) the increase was less significant.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
935.
Ramesh Sarangapani Justin Teeguarden Kathleen P Plotzke James M McKim Melvin E Andersen 《Toxicological sciences》2002,67(2):159-172
Inhalation of octamethylcyclotetrasiloxane (D4) induces CYP2B1/2 protein and causes liver enlargement. We have developed a pharmacodynamic (PD) extension to a physiologically based pharmacokinetic (PBPK) model to characterize these dose-response behaviors. The PD model simulates interactions of D4 with a putative receptor, leading to increased production of cytochrome P450 2B1/2. Induction was modeled with a Hill equation with dissociation constant, Kd, and Hill coefficient, N. Both a 1- and a 5-compartment liver model were evaluated. The PBPK model provided excellent simulations of tissue D4 and hepatic CYP2B1/2 protein concentrations following 6 h/day, 5-day inhalation exposures to 0, 1, 7, 30, 70, 150, 300, 500, 700, or 900 ppm D4. Either the 1- or 5-compartment liver model could accurately simulate increases in CYP2B1/2 protein in the liver. With a 1-compartment liver, Kd and N were 0.67 microM (free liver concentration) and 1.9, respectively. The 5-compartment model used higher N-values (approximately 4.0) and varied Kd between compartments. The fitted 5-compartment model parameters were Kd = 0.67 microM in the midzonal compartment with geometric differences in Kd between compartments of 2.9. On the basis of unbound (free) plasma concentrations, D4 appeared to be a higher potency inducer than phenobarbital (PB). Dose-response curves for increased liver weights had N/mS 1.0 and Kd/mS 3.4 microM, very different values from those for enzyme induction. Exposure concentration leading to a 0.1% increase in CYP2B1/2 protein predicted by the 1- and 5-compartment models were 2.1 ppm and 5.1 ppm, respectively. The 1- and 5-compartment liver models provided very similar fits to the whole liver induction data, excluding the lowest dose, but the 5-compartment liver model had the additional advantage of simultaneously describing the regional induction of CYP2B1/2. 相似文献
936.
The aim of this study was to elucidate the putative role of the gonadotropin releasing hormone (GnRH or LHRH) as an olfactory stimulant in fish. We report for the first time extreme sensitivity of the olfactory organ in the rainbow trout (Oncorhynchus mykiss) to GnRH. Recordings of the electroolfactogram (EOG) showed an electrophysiological response to 10(-16) M GnRH four times the amplitude of the response to a fresh water control stimulus. By stimulating the olfactory epithelium with several GnRH analogs and fragments of the decapeptide, the biologically active region of GnRH could be partly elucidated. The response profile of GnRH differed from that of the positive control odorant L-alanine, suggesting that separate receptors or receptor cells are involved. We propose that this potent odorant may act as a reproductive pheromone in fish. 相似文献
937.
A perinatal audit of 109 neonatal deaths was carried out in three Danish counties (A, B and C) in order to investigate whether differences in the structure of antenatal care, delivery, and neonatal service had any influence on neonatal outcome and whether departure from generally accepted standards of satisfactory perinatal and neonatal care might have contributed to neonatal deaths. In the county (C) characterised by having no intensive neonatal care unit, significantly fewer liveborn infants with a gestational age of less than 28 weeks were reported to the Birth Register. County C had also significantly more potentially avoidable deaths compared with the county (B) which had a neonatal intensive care unit with specially trained staff available around the clock. The neonatal department in county A did not have specially trained doctors available in the hospital around the clock, and some cases of suboptimal care were caused by inadequate staffing and inappropriate decisions made by inexperienced junior doctors. The results indicate that it should be possible to improve the quality by having obstetric departments with access to neonatal intensive care units staffed with qualified personnel around the clock and by intensifying the postgraduate training of professionals performing peri- and neonatal care. 相似文献
938.
The location of the centre of resistance (CR) of various consolidated units of maxillary anterior teeth was determined in this study using human autopsy material. The units studied consisted of two central incisors, four incisors, and six anterior teeth. When horizontal forces were applied the CR for the two- and six-tooth units was located approximately 6.5 mm apical to the bracket position. For the four-tooth unit, CR was placed slightly more occlusally, the distance being 5.0 mm. Applying vertical forces CR was located about 13.0 mm posterior to the bracket position for the two- and four-tooth unit. The incorporation of the canines into the incisor segment resulted in a distal shift of CR of 6 mm. CR for the six anterior teeth was, thus, located on a line 3 mm behind the distal surface of the canines. Increasing force levels had little effect on the location of CR for a given unit. 相似文献
939.
P. Waaddegaard B. J. Hansen S. W. Christensen J. T. Andersen R. Iversen-Hansen H. -G. Iversen 《International urology and nephrology》1991,23(3):245-250
Twenty-one patients with benign prostatic hypertrophy (BPH), and a weight of transurethrally resected tissue exceeding 80
g (Group 1), were compared to a control group of 30 patients with a weight of resected tissue less than 80 g (Group 2) with
regard to the peri-and postoperative course and the symptomatic and urodynamic results of surgery. All patients were followed
12 months postoperatively. In both groups more than 90% of the patients were satisfied with the result of the operation. However,
the obstructive symptoms were better relieved than the irritative symptoms. The group who had large resections performed had
a longer operating time and a greater perioperative blood loss than the group of minor resections. No differences were found
with regard to other peri- or postoperative complications or subjective results. Transurethral resection is safe and efficient
in treating BPH, also with very large prostates. 相似文献
940.
Five patients with long-standing rheumatoid arthritis underwent transmetatar-sal amputation. Operative indications were severe pain on walking, marked deformity of the forefoot, and no effect of conservative treatment. After a median follow-up time of 7 (1-12) years, 4 patients had no pain, all patients could wear normal shoes, and the gait was significantly improved without imbalance. 相似文献