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991.
Cervical examination between 26 and 30 weeks' gestation is described as a method for identifying women at risk for delivery before 34 weeks. Blinded cervical examinations were performed in 185 consecutive women, and 15 (8%) were found to have cervixes dilated 2 or 3 cm. The incidence of delivery before 34 weeks' gestation was 27% in such women compared with 2% in those whose cervixes were undilated or 1 cm. Other factors linked to cervical dilatation included parity and prior preterm delivery. However, parous women with cervical dilatation remained at increased risk for delivery before 34 weeks' gestation. We conclude that early third-trimester cervical examination may be an important adjunct in identifying women at risk for preterm delivery. 相似文献
992.
Localized 31P NMR spectroscopy was used to study the developing human liver in three neonates and one infant, all with neonatal intracranial problems, but normal liver function. A prominent resonance was present in the phosphomonoester (PME) region of the spectrum of the neonates; the PME/ATP ratio was 1.0 +/- 0.4 (repetition time 1 s), compared to the mean adult liver value of 0.2 +/- 0.1. The saturation factor of PME in the neonates was large, indicating that the increase in PME/ATP reflected an increase in relative PME concentration. The chemical shift of the PME peak in the neonatal liver (6.8 +/- 0.1) was similar to that found in neonatal brain, suggesting that phosphorylethanolamine may be a major constituent. The phosphodiester (PDE)/ATP ratio in these patients (0.4 +/- 0.1) was decreased compared with the mean adult value (1.3 +/- 0.2), and the saturation factor of PDE was small. The results from the infant were different from both the neonates and adults; PME/ATP was decreased compared to the neonates, but increased compared to adults. The saturation factor of PDE was increased compared to neonates. The biochemical implications of the observed changes in PME and PDE in paediatric liver are discussed in relation to membrane turnover. 相似文献
993.
J D Cox T F Pajak V A Marcial G E Hanks M Mohiuddin K K Fu R W Byhardt P Rubin 《International journal of radiation oncology, biology, physics》1990,18(3):515-521
A prospective, randomized Phase Ilate/II trial of hyperfractionated radiation therapy was conducted: 1.2 Gy minimum tumor dose was administered twice daily with a minimum interval of 4 hr, 5 days per week. Patients with Stage III and IV carcinomas of the oral cavity, oropharynx, nasopharynx, hypopharynx, and supraglottic larynx were stratified by site, presence or absence of nodal metastases, and performance status. They were assigned to four total doses between 67.2 Gy and 81.6 Gy to all known tumors. The highest dose arm was opened after preliminary assessment indicated acceptable late morbidity rates with the three lower doses. Of 479 patients entered, 260 patients were randomized to the three lower total doses and 237 were analyzed for this preliminary report: 63 were assigned to receive 67.2 Gy, 58 to 72.0 Gy, and 116 to 76.8 Gy. Estimates of grade 4 necrosis at 2 years were 10.0%, 5.1%, and 13.9%, respectively, for patients who received total doses of 67.2 Gy, 72.0 Gy, and 76.8 Gy. There was a suggestion of a trend toward increased local control at 24 months (Kaplan-Meier estimates of 25% for 67.2 Gy, 37% for 72.0 Gy, and 42% for 76.8 Gy) (p = .08). No difference was observed in survival. Assessment of the results using Cox regression models to correct for slight inequalities of pretreatment prognostic variables supported a total dose-tumor control relationship (p = .054). Results for the lowest dose arm were comparable to previous RTOG studies of common fractionation with similar total doses. The higher local control rates with 72.0 and 76.8 Gy using hyperfractionated radiation therapy suggest an improvement in outcome with radiation therapy for advanced carcinomas of the upper aerodigestive tracts. These preliminary findings have led to a Phase III comparison of hyperfractionated radiation therapy with 1.2 Gy b.i.d. with standard fractionation. 相似文献
994.
This paper explores the immediate psychological and physiological effects of aversive visual stimuli, represented as pictures of war, in a balanced mixed design (n = 24). The moderating effects of individual differences in locus of control and sex were examined, along with those of a requirement to report on the stimuli presented. The results indicated a fractionation of the autonomic response with electrodermal measures (EDA) and salivary function showing a sympathetic type response to war slides whilst measures of cardiac activity (heart rate and heart rate variability) tended to show increased parasympathetic activity over the response to neutral slides. Psychological measures showed an increase in self-reported stress, higher disturbance ratings and unprompted reports of various coping strategies (postexperimental interviews) in response to war slides. Additionally, self reported arousal and EDA's proved sensitive to the report requirement and cardiac activity appeared to be tied to individual differences in terms of locus of control. Although the physiological results could be taken as congruent with Hare's (1972) suggestion that 'morbid curiosity' accompanies the viewing of aversive stimuli, psychological measures tended to disconfirm this interpretation. The situational determinants of the cardiac response are discussed as a solution to the paradoxical cardiac response elicited with aversive visual stimuli, along with individual styles of coping with aversive situations which may be reflected in individual's locus of control. 相似文献
995.
Treatment of disseminated herpes simplex virus in pregnancy with parenteral acyclovir. A case report
Disseminated herpes simplex virus infection in a pregnant woman was successfully treated with acyclovir. Similar reported cases have suggested that acyclovir may be suitable for the treatment of disseminated or severe primary herpes in pregnant women. 相似文献
996.
997.
An Archive of longitudinal growth data, accessible to research workers under the usual safeguards, has been set up in the Department of Growth and Development. The present S.I.R. database contains seven British and one Indian study. The Archive is open to receive other contributions if researchers wish. 相似文献
998.
A Harada J S Tweddell R B Schuessler B H Branham J P Boineau J L Cox 《The Annals of thoracic surgery》1990,49(4):649-655
This study evaluated potential distribution mapping as a method for localizing the site of origin of ventricular tachycardia (VT). In contrast to conventional activation time maps, potential distribution maps require less editing and thus can be more automated and rapidly processed for interpretation of multiple beats of VT. As a series of potential distribution maps during VT is required for detailed analysis, an on-line computerized system was designed to display potential distribution maps sequentially at 1-ms intervals as a color movie. Potential distribution maps and activation time maps were constructed from 182 epicardial and endocardial unipolar electrodes during 12 episodes of reproducible monomorphic VT in 9 dogs four to six days after experimental myocardial infarction (mean cycle length, 162 +/- 21 ms). At the onset of each depolarization during VT, a potential minimum abruptly developed on the surviving epicardium and another on the surviving endocardium of the left ventricle, both immediately adjacent to the subendocardial infarct. These two minima on the initial potential distribution maps corresponded to the sites of earliest epicardial and endocardial activation breakthrough recorded on the activation time maps. These two minima subsequently expanded or moved into the adjacent area and coincided with the spread of activation fronts on the epicardial and endocardial surfaces. Thus, the rapid display of sequential, computerized potential distribution maps of multiple beats of VT provides a dynamic means of identifying the site of origin of VT, and therefore should facilitate intraoperative mapping. 相似文献
999.
Pituitary infarction occurring immediately after TRH injection (200 micrograms) is reported in a patient with gigantism due to a growth hormone-secreting pituitary macroadenoma. Evidence of infarction was seen in CSF and in serial CT scans. Regression of symptoms and sign of acromegaly, abolition of abnormal growth hormone secretion, and virtually complete anterior and partial posterior pituitary failure rapidly followed. The infarction was probably initiated by a hypertensive response to TRH. TRH testing in acromegalic subjects may require smaller doses of TRH to avoid unwanted pressor responses. 相似文献
1000.
Comparison of catheter surface morphologies 总被引:1,自引:0,他引:1
A J Cox 《British journal of urology》1990,65(1):55-60
The surface morphologies of different generic types of Foley catheter have been investigated using scanning electron microscopy (SEM). The characteristic features of each material are illustrated and it is shown that distinct differences exist between the inner and outer surfaces of latex-based catheters; these differences are attributed to the methods of manufacture. The possible relations between morphology and performance in situ are discussed. 相似文献