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Background: Previous studies have shown that propofol and sevoflurane enhance the function of [gamma]-aminobutyric acid type A (GABAA) receptors. However, it is not known whether these two drugs modulate the same molecular pathways. In addition, little is known about receptor function in the presence of both propofol and sevoflurane. The aim of this study was to better understand the interactions of propofol and sevoflurane with the GABAA receptor.

Methods: Wild-type [alpha]1, [beta]2, [gamma]2s GABAA receptor subunit complementary DNAs were transfected into human embryonic kidney cells grown on glass coverslips using a calcium phosphate transfection method. After transfection (36-72 h), cells were whole cell patch clamped and exposed to combinations of the following: 0.3-1,000 [mu]m [gamma]-aminobutyric acid (GABA), 0-10 [mu]m propofol, and 0-1,650 [mu]m sevoflurane. Chemicals were delivered to the cells using two 10-channel infusion pumps and a rapid solution exchanger.

Results: Both propofol and sevoflurane alone enhanced the amplitude of GABAA receptor responses to submaximal concentrations of GABA in a dose-dependent manner. The enhancement was underpinned by an increase in the apparent affinity of the receptor for GABA. Coapplication of both anesthetics further enhanced the apparent affinity of the receptor for GABA.  相似文献   

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After the interaction of estrogen with the ligand binding domain (LBD) of mouse estrogen receptor‐α (mERα) and hormone‐responsive elements of target genes, many nuclear proteins are recruited to regulate the expression of specific genes. Because it is not known which brain proteins interact with LBD or whether these proteins vary with age and sex, we used pull‐down assay and far Western blotting to detect five nuclear proteins of 160, 140, 87, 60, and 46 kD in the mouse brain. These interacting proteins were identified as PELP1, RIP140, PGC1α, BAF60, and ADA3, respectively. The level of PELP1, RIP140, PGC1α, and BAF60 decreased drastically in old compared with adult male mice, whereas the ADA3 level showed no significant change. PELP1, PGC1α, and BAF60 levels were lower in old male compared with female mice. Thus we report the identification and interaction of five nuclear proteins with mERα‐LBD, indicating their role in estrogen signaling and brain functions during aging. © 2009 Wiley‐Liss, Inc.  相似文献   
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A 27-month longitudinal study of 140 Bangladeshi mothers living in three tea gardens examined the effect of maternal factors (mother's age, number of live births, birth interval, and mother's work status) and sex of the infant on the duration and bout frequency of breastfeeding over 8-hr daytime periods. Prolonged breastfeeding of the infant was observed, but there was a sharp decline in duration of breastfeeding over the first 6 months, followed by a more gradual diminution thereafter. The feeding bouts showed a different pattern, with a more gradual decline over time. Housewives consistently showed a greater duration and bout frequency than women in paid employment as tea-pluckers. Over the first 6 months, primigravid mothers breastfed more frequently, but not thereafter. Older mothers (>35 years of age) breastfed with higher frequency during the first 2 months, but thereafter, the bout frequency decreased with increasing age of the infant. Over the 27-month study, maternal work status was the main factor associated with the duration and frequency of breastfeeding, with significantly higher frequency and duration among housewives. However, in the first 6 months after birth, there was very little difference in frequency or duration of breastfeeding between tea-workers and housewives, indicating that working mothers probably adjusted their time to breastfeed their infants before going, or after coming back, from work.  相似文献   
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A 50 year old man with a two month history of upper abdominal pain and a one month history of anorexia and weight loss, presented with icterus and evidence of peritonitis. Laparotomy revealed biliary peritonitis which had been caused by a rupture of the fundus of the gallbladder. The common bile duct was dilated and there was a large growth in the head of the pancreas with multiple hepatic metastases. A cholecysto-jejunostomy and gastrojejunostomy were done and the patient had an uneventful recovery.  相似文献   
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Sixteen patients receiving percutaneous endoscopic gastrostomy (PEG) feeding following a period of nasogastric (NG) feeding were investigated to assess acceptance and identify problems by means of a questionnaire. PEG was considered to be superior to NG feeding in terms of tolerance and cosmetic acceptance by 81% and 88% of participants respectively ( P < 0.001). Pain was an infrequent problem. Interruptions to feeding were consideed to be more common with NG feeding by 50% of participants; 38% considered interruptions equally common with both PEG and NG, and 12% considered interruptions more common with PEG feeding ( P = NS). The time for care was equivalent for both methods. Seventy-five percent considered PEG to have made a valuable contribution to enteral feeding. Leakage was however considered to be more frequent in PEG feeding by 81% of participants (compared to 12% who considered leakage to be more common with NG feeding; P < 0.001) and leakage was more frequent at die junctions in the catheter rather than from the stoma. Thirty-one percent of patients with PEG had needed systemic antibiotics for stomal infections. All patients with both PEG and NG feeding needed professional help. Sixty-two percent needed professional help more frequently with PEG than with NG feeding (compared to 19% who considered that the NG tube needed professional help more frequently; P <0.05). We conclude that leakage and infections are major problems in PEG enteral feeding.  相似文献   
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