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951.
952.
A López Bernal D J Hansell S Alexander A C Turnbull 《British journal of obstetrics and gynaecology》1987,94(11):1052-1058
The production of progesterone from pregnenolone, of cortisol from cortisone and of prostaglandin E (PGE) under basal and arachidonic acid-stimulated conditions was measured in cells dispersed from chorion and decidua. The cells were obtained after delivery from four groups of women: following spontaneous labour at term (38-42 weeks gestation), at elective caesarean section at term before the onset of labour, after induced labour at term, and after uncomplicated preterm (27-36 weeks) labour. Chorionic cells had a high progesterone output with relatively low cortisol and PGE production, whereas decidual cells had a high cortisol and PGE production rate. Free arachidonic acid stimulated PGE production in both decidual and chorionic cells. There were no significant differences in either steroid or PGE production among the four groups studied. These data suggest that steroid dehydrogenase activity in choriodecidual cells is not related to the mode of onset of labour and that the increased prostaglandin production in intrauterine tissues associated with parturition is due to enhanced availability of arachidonic acid. 相似文献
953.
Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care. 相似文献
954.
Y. O. Karatasso I. V. Logunova M. G. Sergeeva E. N. Nikolaev S. D. Varfolomeev V. V. Chistyakov 《Pharmaceutical Chemistry Journal》2007,41(3):166-169
A highly sensitive method for the quantitative determination of a potential antiarrhythmic drug (OF-7976) in the blood plasma
has been developed. The method is based on the electron spray ionization/mass spectrometry (ESI-MS) technique without preliminary
chromatographic separation and makes use of nibentan as the internal standard. A linear relationship between drug concentration
and the peak intensity of ions of the analyzed substance (m/z = 398) and the internal standard (m/z = 382) is established. The detection limit is 3 ng/(0.5 ml plasma). The method is linear from 3 to 25 ng/(0.5 ml plasma)
with a correlation coefficient of 0.98. The coefficient of variation was less than 7 %.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 3, pp. 45–48, March, 2007. 相似文献
955.
Alan Willmore Tim Sladden Lucy Bates Craig B Dalton 《International journal of health geographics》2006,5(1):30-14
Background
To determine patterns of childhood lead exposure in a community living near a lead and zinc smelter in North Lake Macquarie, Australia between 1991 and 2002. 相似文献956.
957.
Signe S?nderkaer Marianne Schmiegelow Henrik Carstensen Lars B?geskov Nielsen J?rn Müller Kjeld Schmiegelow 《Journal of clinical oncology》2003,21(7):1347-1351
PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits. 相似文献
958.
Maximum anchorage often presents a problem that is difficult to solve during orthodontic tooth movement. Stationary, skeletal anchorage can be achieved in a simple, minimally-invasive manner, and unwanted tooth movements in opposite directions can be prevented by using transmucosally-inserted bone screws.Our initial experience using the FAMI screw as an orthodontic micro-implant proved to be clinically and histologically successful. 相似文献
959.
960.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献