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441.
In conditions of alternating light and dark, juvenile Penaeus merguiensis de Man are more active during the dark phase. The rhythm persists in continuous dim red light, but not in continuous bright white light. The period of circadian rhythm shown in continuous dim red light varies between individuals from 22.75 to 26.0 h, with a mean of 23.8 h. The response of prawns to an artificially produced tidal situation is mediated by the presence or absence of water flow. No endogenous component of this tidal rhythm was demonstrated. There is an irregular short-term rhythm (period 2 to 3 h). It is suggested that this allows starved prawns to conserve energy.  相似文献   
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Book reviews     
ENGLISH STRUCTURE PLANNING

Eds: D. T. Cross and M. R. Bristow

Pion Ltd., London, 1983. £16.00.

AN INTRODUCTION TO URBAN RENEWAL

Michael S. Gibson and Michael J. Longstaff

London: Hutchinson, 1982. 384 pp.

INTEGRATED URBAN MODELS

S. H. Putman

Pion Ltd., 1983, 332 pp.

EXPLANATION PREDICTION AND PLANNING: THE LOWRY MODEL

M. T. Webber

Pion Ltd., London, 1984, 214 pp.

THE GOVERNMENT AND ADMINISTRATION OF METROPOLITAN AREAS IN WESTERN DEMOCRACIES

Alan Norton

Institute of Local Government Studies, University of Birmingham, 1983, 57 pp.

THE MANAGEMENT OF SEMI‐NATURAL WOODLAND

County Planning Officers’ Society (available from Hampshire County Planning Dept., price £2.00).  相似文献   

446.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
447.
In order to verify whether fetal and maternal adrenal gland suppression induces effects on fetal behaviour, triamcinolone was administered to five healthy pregnant women at 35 weeks of gestation. Five patients of the same gestational age were used as control. Fetal heart rate (FHR) and fetal movements were recorded continuously over 2-h interval by means of cardiotocography. After 3 weeks (38 weeks of gestation) the recordings were repeated without drug administration. Cortisol, adrenocorticotropin hormone, 17 β-estradiol and unconjugated estriol were measured at the same time every 2 h in maternal peripheral plasma. At 35 weeks we found a loss of circadian rhythms of the hormones investigated and modifications of ultradian and circadian patterns of FHR in the treated group with respect to the control. No differences in hormonal and biophysical parameters were found between the two groups after the end of treatment (38 weeks). These data suggest that the inhibition of fetal and maternal adrenal glands could cause modifications of FHR patterns.  相似文献   
448.
A quantitative method for cholinesterases in amniotic fluid using the non-specific substrate α naphthyl acetate and the cholinesterase-specific inhibitor, eserine, is described. This assay was used to test 671 samples of amniotic fluid. The diagnoses for fetal ONTDs, based on the levels of AChE + ChE, were compared with those made for the same samples by the AFP method. Correct diagnoses were made by both methods with amniotic fluid from 35 women carrying fetuses with ONTDs and 631 carrying normal fetuses. There were five false-positive test results for normal fetuses by both methods when the cut-off points were 5 standard deviations above the mean for AFP and above the upper limit of the normal range (7. 5 milliunits) for cholinesterase (AChE + ChE). None of the false-positive samples from either method had the acetylcholinesterase band of activity characteristic of ONTDs after gel electrophoresis. In addition to the above 671 samples, 37 pregnancies with serious fetal abnormalities other than ONTDs were tested. Two were identified by both the AFP and AChE + ChE methods, two more by AFP assay and one other by the AChE + ChE assay.  相似文献   
449.
After a lapse of almost two decades, US energy and mining companies are once again involving themselves with worker housing. Reinvolvement began in the 1970s. It is in response to a recognition of the fiscal consequences of project delays and an industry responsibility to both workers and project area communities. It differs from the heavy reliance on company towns which were prevalent in the US during the 19th and early 20th Centuries. Industry involvement now relies not only on supply, but on stimulation. A greater variety of housing initiatives is being utilised and a company must carefully select the housing initiative best suited to its circumstances. These initiatives need to be guided by the following set of decision guidelines: (1) housing function; (2) housing user; (3) housing type and quantity needs; (4) monetary expectations; (5) role of the industry; (6) housing unit location; (7) responsibilities after housing is completed; and (8) amenities and community sharing. Then, housing involvement must be reviewed in light of past and present industry experiences. Innovative ideas need to be evaluated with respect to proven initiatives, as well as their presumed goal and potential for success.Study performed under Contract No. DE-AC02-76CH00016 with the U.S. Department of Energy  相似文献   
450.
Congenital cystic adenomatoid malformation of the lung can be detected with antenatal ultrasound as hyperechogenic areas in the fetal chest. Associated extrapulmonary malformations as well as chromosomal aberrations are described as very rare. We present a case report of a fetus in the 23rd week of gestation who showed in the course of a routine ultrasound screening a large number of malformations: holoprosencephaly, arrhinencephaly, cleft palate, CCAM type III of the right inferior pulmonary lobe, ventricular septal defect and bilateral clubfeet. Chromosome analysis confirmed the suspicion of trisomy 13. The present case shows how important it is—even with malformations that are rarely accompanied by associated anomalies and which have a very good prognosis—to carry out a directed diagnosis including a fetal karyotyping. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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