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1.
Association between PCBs and lower embryonic weight in black-crowned night herons in San Francisco Bay 总被引:3,自引:0,他引:3
D J Hoffman B A Rattner C M Bunck A Krynitsky H M Ohlendorf R W Lowe 《Journal of toxicology and environmental health》1986,19(3):383-391
Reproductive problems, including congenital malformations, reduced hatching success, and decreased survival of hatchlings, have been observed in colonial-nesting water birds at the San Francisco Bay National Wildlife Refuge (SFBNWR). Twenty-four black-crowned night heron (Nycticorax nycticorax) eggs were collected from SFBNWR in 1983. Twelve of these were collected from separate nests when late-stage embryos were pipping, and an additional egg was randomly collected from each nest for organochlorine analysis. Overt anomalies and skeletal defects were not apparent. Embryonic weights (with partially absorbed yolk sacs removed) were 15% lower (p less than 0.05) in SFBNWR embryos compared to control embryos from the Patuxent Wildlife Research Center (PWRC). Crown-rump length and femur length were shorter for SFBNWR embryos. The geometric mean polychlorinated biphenyl (PCB) concentration in SFBNWR eggs was 4.1 ppm wet weight, with a range of 0.8-52.0 ppm. A negative correlation (r = -0.61; p less than 0.05) existed between embryonic weight and log-transformed PCB residues in whole eggs collected from the same nest at SFBNWR, suggesting a possible impact of PCBs on embryonic growth. A correlation with embryonic weight did not occur for DDE [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene] residues. Liver microsomal aryl hydrocarbon hydroxylase activity was neither significantly elevated nor correlated with PCB, DDE, or PCB plus DDE log-transformed residues. It is unknown whether the apparent association between PCBs and lower weight is persistent through hatching. 相似文献
2.
We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications. 相似文献
3.
Esmolol for treatment of intraoperative tachycardia and/or hypertension in patients having cardiac operations. Bolus loading technique 总被引:1,自引:0,他引:1
J G Reves N D Croughwell E Hawkins L R Smith J R Jacobs S Rankin J Lowe P VanTrigt 《The Journal of thoracic and cardiovascular surgery》1990,100(2):221-227
Esmolol, administered as a bolus followed by continuous infusion, was used to treat the occurrence of transient tachycardia and hypertension or tachycardia alone before cardiopulmonary bypass in 45 patients. The study was conducted in two phases. Phase I (15 patients) was a dose-finding study and phase II (30 patients) was a randomized, double-blind, placebo-controlled efficacy study. All patients received the last dose of their usual beta-adrenergic blocker the night before the operation and were anesthetized with midazolam, vecuronium, and enflurane in oxygen. Treatment criteria were either a systolic blood pressure greater than 140 mm Hg and a heart rate greater than 70 or a heart rate greater than 80 beats/min. In phase I, graduated doses of esmolol were given to successive patients. A dose of 80 mg followed by a 12 mg/min infusion was declared effective. Phase II patients were randomized to receive esmolol (n = 16) or placebo (n = 14). Hemodynamic data were collected at baseline and 1, 3, 5, and 10 minutes after the administration of esmolol. Plasma norepinephrine was measured at baseline, 1, and 10 minutes. Esmolol significantly (p less than 0.05) reduced heart rate at 1, 3, 5, and 10 minutes but did not change blood pressure, pulmonary artery diastolic pressure, right atrial pressure, cardiac output, or systemic vascular resistance. Our results show that a bolus loading dose of esmolol is safe and effective in the treatment of tachycardia in patients with ischemic heart disease and that esmolol rapidly blocks the beta-adrenergic effects of norepinephrine associated with surgical stress. 相似文献
4.
Joseph D. obias MD Sandra Lowe MD George W. Holcomb III MD 《Journal of clinical anesthesia》1992,4(6):484-486
The case of a 3-day-old infant with Beckwith-Wiedemann syndrome who required anesthetic care during closure of an abdominal wall defect is presented. Beckwith-Wiedemann syndrome comprises a constellation of clinical features, including macroglossia, macrosomia, omphalocele, visceromegaly, mild microcephaly, facial nevus flammeus, horizontal earlobe creases, and renal medullary dysplasia. Due to the high rate of omphalocele in this syndrome, anesthetic care is frequently required during the neonatal period. Many of these infants (greater than 50%) are born prematurely. Therefore, their anesthetic care may be further complicated by associated diseases of prematurity, such as hyaline membrane disease. Additional anesthetic implications of this syndrome relate to the occurrence and management of hypoglycemia and polycythemia. Careful intraoperative management of glucose homeostasis is particularly important, since eventual neurologic outcome and intelligence will be normal provided prolonged neonatal hypoglycemia is avoided. Preoperative evaluation of the cardiac and genitourinary system, including echocardiography and renal ultrasound, are recommended because of the frequent occurrence of associated anomalies with omphalocele. 相似文献
5.
R F Lowe 《Australian and New Zealand journal of ophthalmology》1987,15(1):83-87
Symptoms that persist after operations for angle-closure glaucoma arise from different causes. In the presence of open peripheral iridectomies miotics may be beneficial or may close angles; wide pupil dilatation by phenylephrine used to diminish posterior synechiae may close angles; cycloplegic mydriatics will close some angles and open others. Unexpected bizarre reactions to eye drops may occur. Persistent chronic glaucoma will be more common after laser iridotomy than after correctly assessed filtering operations. The importance of gonioscopy in diagnosis and management is emphasised. 相似文献
6.
M. G. M Cormican D. J Lowe P Keane J Flynn D O’Toole 《Irish journal of medical science》1991,160(4):112-113
The capacity of blood pressure cuffs to act as vehicles of hospital infection has been recognised. We describe the microbial
flora of in-use DINAMAP blood pressure cuffs used in the operating theatres and one recovery room in a teaching hospital.
Our results show significant microbial contamination of in-use blood pressure cuffs. 相似文献
7.
P J Harrison A W Procter A J Barton S L Lowe A Najlerahim P H Bertolucci D M Bowen R C Pearson 《Brain research. Molecular brain research》1991,9(1-2):161-164
In situ hybridization histochemistry has been used to study the amount of M1 muscarinic receptor mRNA in temporal cortex from subjects with Alzheimer's disease and other neurodegenerative disorders, where the duration of terminal coma was known. Total polyadenylated mRNA and glutamate decarboxylase activity were also measured. Both muscarinic receptor mRNA and enzyme activity showed a significant decline with increasing duration of terminal coma, but were not related to diagnosis. Polyadenylated mRNA signal did not show an association with coma. These data indicate the need to consider the nature of the terminal illness in post mortem studies of mRNA as well as for neurochemical research. 相似文献
8.
9.
Amaya Gillespie Warren Stanton John B. Lowe Beth Hunter 《The Journal of school health》1995,65(10):432-437
ABSTRACT: This study obtained input from Australian student smokers approximately 15 years old, which may be useful in designing school-based smoking cessation programs. The sample was analyzed by previous quitting experience and intentions to quit. The order of preference for assistance options and incentives for quitting was similar across all groups: however, those who previously attempted to quit (previous quitters) and those who intended to quit (intenders) in the future were significantly more likely than non-quitters and non-intenders to find assistance options for quitting acceptable. The potential for saving money emerged as an important variable in convincing all groups of smokers not to smoke, and using personal willpower and cutting down slowly were identified as important in actual attempts to quit. The need for programs to be free and for friends to be supportive also was evident across all groups. 相似文献
10.
Jill L. Oswalt MD Jerris R. Hedges MD Betsy E. Soifer MD PhD Daniel K. Lowe MD 《The American journal of emergency medicine》1992,10(6):511-514
The timing of trauma patient intubation is dependent on clinical presentation and clinician judgment. We sought to correlate the timing of intubation with the presenting of physiologic parameters and clinical outcome to identify potential quality assurance audit filters. Patients (n = 82) were grouped by timing of intubation: PREHOSPITAL, paramedic intubation; IMMEDIATE, within 10 minutes of arrival; DELAYED, beyond 10 minutes but within 2 hours of arrival; and NONURGENT, beyond 2 hours or at the time of surgery. While mean revised trauma scores and Glasgow Coma Scale (GCS) scores differed for the groups, the mean length of hospital stay and the incidence of aspiration pneumonia were not significantly different. In the DELAYED group, 80% of those who developed aspiration pneumonia had a GCS < or = 13. Patients in the NONURGENT group were older and commonly presented with tachypnea. The survival rate for the NONURGENT group was lower than predicted by the TRISS method (P = .004). A GCS < or = 13 and age greater than 50 years with presenting respiratory rates of more than 25 breaths/min represent potential trauma intubation audit filters. 相似文献