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151.
D. Lemke 《Die Naturwissenschaften》1983,70(11):540-549
Infrared observations with ground-based and balloon-borne telescopes are hampered by thermal background radiation and absorption caused by the earth's atmosphere. A sensitivity gain of up to three orders of magnitude can be obtained under the low photon background conditions of a helium-cooled space telescope. Physical properties of photodetectors and bolometers as well as their application to the new infrared telescopes aboard satellites and Spacelab are discussed. 相似文献
152.
153.
J. Heinze H. Remmert F. L. Boschke D. Reinen L. Jaenicke 《Die Naturwissenschaften》1983,70(11):575-576
154.
155.
Research in molecular neurobiology has recently entered a new phase of rapid development as a result of the application of the techniques of molecular genetics. This is illustrated by recent work on the electric ray (Torpedo marmorata and T. californica), whose electric organ is a rich source of cholinergic synapses. Other examples from recent literature of the application of the recombinant DNA technique to the mammalian central nervous system are given and possible future developments are discussed. 相似文献
156.
157.
Mary C. Phelan Ph.D. Robert A. Saul Thompson A. Gailey Jr Steven A. Skinner 《黑龙江环境通报》1995,15(3):274-277
Mosaicism for the Wolf-Hirschhorn syndrome, del(4)(p16), is extremely rare and has not been reported in association with a numerical chromosome abnormality. We report the prenatal diagnosis of mosaic del(4)(p16) and non-mosaic trisomy 21 in a 16-week female fetus. The pregnancy ended in spontaneous abortion at 34 weeks secondary to fetal demise. The fetus had features of both 4p – and trisomy 21. 相似文献
158.
Ariel Weissman Reuwen Achiron M.D. Jacob Kuint Shlomo Lipitz Shlomo Mashiach Itamar Avigad 《黑龙江环境通报》1994,14(9):888-891
A case of gastric outlet obstruction diagnosed prenatally at 22 weeks' gestation is described. The differential diagnosis and the clinical management of this rare condition are discussed, and an updated literature review is presented. 相似文献
159.
Catherine Donner M.D. Corinne Liesnard Françoise Brancart Frederic Rodesch 《黑龙江环境通报》1994,14(11):1055-1059
Cytomegalovirus (CMV) is the most common cause of intrauterine infection. Recent publications show amniocentesis to have an 81–100 per cent sensitivity in antenatal diagnosis after 21 weeks' gestation. Testing before 21 weeks' gestation is less well documented. We performed 36 amniocenteses between 14 and 20 weeks' gestation. The sensitivity was 45 per cent and the specificity 100 per cent. Implications and possible causes of this low sensitivity are discussed. 相似文献
160.
Ellen Sidransky Susan H. Black Dawn M. Soenksen Shirley L. Jones Andrew D. Dorfmann Joseph D. Schulman MD 《黑龙江环境通报》1990,10(9):583-586
Chorionic villus sampling (CVS) with either transcervical catheters or transabdominal needles is a widely-accepted method for prenatal diagnosis. However, there exists a small subset of patients in whom sampling is difficult or impossible with either route because of individual anatomic variations. A new method of chorionic villus biopsy has been developed to circumvent these problems, utilizing transvaginal chorionic needle aspiration guided by an intravaginal ultrasound probe. This technique was performed successfully in 15 patients in whom villi could not be obtained by either of the conventional methods. This method now makes CVS possible in essentially all women regardless of their uterine anatomy or placental placement; it may also prove useful for very early chorionic sampling. 相似文献