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151.
K. E. Kaissling G. Kasang H. J. Bestmann W. Stransky O. Vostrowsky 《Die Naturwissenschaften》1978,65(7):382-384
The female silkmoth Bombyx mori L. emits a second pheromone component bombykal (E-10, Z-12-hexade-cadien-1-al) in addition to the well-known sexual attractant bombykol (E-10, Z-12-hexadecadien-1-ol). Bombykal stimulates its own specialized and highly sensitive olfactory cells of the male moth. Surprisingly, the aldehyde inhibits the release of the male's wing-fluttering response to bombykol. 相似文献
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As screening for Down syndrome becomes increasingly sophisticated, it is important to evaluate the newer technologies in terms of their cost-effectiveness. One recent addition to Down syndrome screening programmes is maternal serum unconjugated oestriol (uE3), especially when used in conjunction with maternal serum α-fetoprotein and human chorionic gonadotropin. Using assumptions used in a California proposal to justify an expanded screening programme for Down syndrome, we calculated both the average and the incremental cost-effectiveness of adding uE3. Using the base case assumptions, including an $8 fee for the uE3, the incremental cost-effectiveness of adding uE3 to the proposed California programme is $119 100 per case detected, a value that compares favourably with other Down syndrome screening programmes. The sensitivity analysis supports this conclusion over a wide range of assumptions. However, because of the uncertainty with some key data, it is still too early to fully support the inclusion of uE3 in Down syndrome screening programmes. 相似文献
155.
Dr. R. J. A. Wanders R. B. H. Schutgens H. van den Bosch J. M. Tager W. J. Kleijer 《黑龙江环境通报》1991,11(4):253-261
In recent years, an increasing number of inherited diseases in man have been recognized in which there is an impairment in the peroxisomal β-oxidation of very-long-chain fatty acids. In general, these disorders are associated with severe neurological and physical abnormalities and death within the first years of life. In this paper we describe our experience with regard to the prenatal diagnosis of a number of different inborn errors of peroxisomal β-oxidation. Eleven pregnancies at risk were monitored by measuring very-long-chain fatty acid levels as well as very-long-chain fatty acid β-oxidation in cultured chorionic villous fibroblasts and/or amniotic fluid cells. Five affected fetuses were identified. It is concluded that prenatal diagnosis in this group of diseases can be done reliably using cultured chorionic villous fibroblasts or amniotic fluid cells. 相似文献
156.
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
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Plasticity of honeybee castes 总被引:1,自引:0,他引:1
160.
Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible. 相似文献