摘要:

AbstractPregnant rats were treated daily with intramuscular injections of 5 or 10 mg cortisone acetate dissolved in 0.5 ml normal saline, or orally with 20,000 IU vitamin D2dissolved in 0.5 ml olive oil, or both. Controls received olive oil and normal saline, or vitamin D2. Treatment was from day 8 or 10 of gestation until the animals were killed on day 18, 20, or 22. The higher dose of cortisone shortened the diaphyses and epiphyses of long bones. Concomitant administration of vitamin D2caused further bone shortening and hypomineralization. The main microscopic alterations in the fetal bones of cortisone‐treated rats were changes in cartilaginous intercellular substance, narrowing of the hypertrophic and calcifying cartilage cell layer, and inhibition of endochondral ossification. Bone trabeculae were very wide and irregular. The bone matrix had abnormal staining properties. Bone marrow spaces were obliterated and contained a very large number of fibroblasts, preosteoblasts, and osteoclasts. The number of osteoclasts was further increased by treatment with vitamin D2. It is presumed that cortisone passed through the placenta and affected fetal bones, causing the microscopic changes. Concomitant administration of vitamin D2potentiated the effects of cortisone on bone, and also produced certain specific change

ISSN:0040-3709    

DOI:10.1002/tera.1420040402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThe radiotoxic effect of continuous infusion of3H‐TdR into rats from day 9 of pregnancy till term has been studied using 288, 576, 864, 1152, and 1440 μCi/day/rat. In the offspring impaired development, decreasing regenerating capacity, malformations, and lethality occurred and were found to be dose dependent. In general, these radiotoxic effects were significant only at higher dose levels. Chromosomal abnormalities also showed a dose dependency, which was discernible even at the lowest level of activi

ISSN:0040-3709    

DOI:10.1002/tera.1420040403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractTwenty infants born to mothers who contracted rubella in the first 20 weeks of gestation were compared to 20 controls with regard to dermatoglyphic pattern asymmetry on 11 regions of the hands and feet, dermatoglyphic orientation asymmetry in these regions, the measured and absolute values of the differences in location of the distal axial triradius on left and right hands, the variance of these differences, and the intraclass correlation coefficient of the position of the axial triradius on left and right hands. Within the experimental and control groups comparisons were also made between subsets matched for symmetric hypothenar patterns and between subsets of the same sex within a restricted birth‐weight range. The trends in all cases indicated that, contrary to the hypothesis, all measures of asymmetry were decreased in the rubella infants. Asymmetry thus seems unlikely to be a useful marker for a human teratogen with effects similar to those of rubell

ISSN:0040-3709    

DOI:10.1002/tera.1420040404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThe upper limbs of 21‐day‐old thalidomide‐treated rabbit fetuses were studied macroscopically, histologically, and histochemically. The deformed limbs were arthrogrypotic, twisted, or medially rotated and inverted. Often these malformations were coupled with anomalies of the thumb. One or more of the preaxial bones or their primordia were either anomalous or missing. The degree of the induced dysmelia could be recognized by the graded severity of the histology. The least severely affected limbs exhibited defects of ossification and/or chondrification, whereas more severely affected ones contained atrophic chondrocytes, undifferentiated mesenchyme, or absence of primordia. In the deformed limbs glycogen was retained in the hypertrophic and calcified chondrocytes and glycogen granules were dispersed in reduced thenar structures, but alkaline phosphatase activity was reduced or absent in the same areas. There were no detectable differences in the amount or distribution of acid mucopolysaccharides between abnormal and control limbs. However calcium deposition in the cartilaginous matrices was reduced or absent in the abnormal limbs. In limbs with reduced amounts of osseous tissue there was no evidence of histochemical aberration in the deposited bone. It would appear, therefore, that thalidomide affected mesenchymal derivatives at various stages of development; that it was associated directly or indirectly with the utilization of glycogen and the production of alkaline phosphatase; and that its influence was expressed by aberrations in the chondrification and calcification processes during later fetal develo

ISSN:0040-3709    

DOI:10.1002/tera.1420040405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractHamster embryos were injected intraamniotically (ia) with 6‐aminonicotinamide (6‐AN) on gestation day 7, 8, or 9 and examined near term. Control treated embryos received 5 μl of water, a needle puncture without injection, or no treatment, and had low rates of resorption and malformation. 6‐AN injected ia produced offspring with multiple defects including exencephaly, cleft palate, anophthalmia, micrognathia, and hydrocephalus. In contrast to day‐8 and ‐9 embryos, which responded to 5‐μg doses of 6‐AN, day‐7 embryos required 50–100 μg before exhi

ISSN:0040-3709    

DOI:10.1002/tera.1420040406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractFour partially duplicated newborn rabbits were observed in 252 births in the inbred strain Y at The Jackson Laboratory within a 12‐month period. Two of these were full sibs and a third was a half sib of these two sets. This frequency is significant and highly suggestive of genetic transmission. All of the conjoined twins were posteriorly duplicated in various degrees. One was equally conjoined, two were unequal, and the fourth was polydactylous with a large intra abdominal teratoma. Abnormalities were found in both the skeleton and internal organ system

ISSN:0040-3709    

DOI:10.1002/tera.1420040407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractChick embryos of 2–14 days of age were incubated in 13% oxygen for 5 days. Experimental embryos demonstrated lowered red blood cell levels, enhanced mean erythrocyte volumes, greater percentages of immature red blood cell stages, and depressed embryonic weights and stages when compared with their controls. Generally, embryos older than 13 days at the termination of the hypoxic incubation were less affected by the low oxygen treatment than younger one

ISSN:0040-3709    

DOI:10.1002/tera.1420040408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractChick embryos of 11–13 somites, which were cultured 48 hours on insulin‐containing medium, showed deformation of the brain and posterior trunk, and inhibited accumulation of DNA, RNA, and protein contents. These effects became more pronounced with increased insulin dose. Embryos transferred to insulin‐free medium after 2 or 3 hours' exposure to 4 U/ml insulin showed a similar morphological response as embryos continuously exposed to the same dose. Quantitation of DNA, RNA, and protein contents indicated a more severe inhibition in embryos of the continuously exposed group than in those of the briefly exposed group, although embryos of both groups were significantly inhibited relative to their controls. Region‐specific action of insulin was demonstrated in terms of the time at which each region of insulin‐treated embryos first showed reduction in DNA, RNA, or protein content. The brain was the most susceptible region to insulin action; the trunk regions responded later; and the heart and extraembryonic membranes showed no significant effect of insulin treatment. At the molecular level nucleic acid content was most influenced by insulin treatment. Reduction in DNA content of whole embryos, or of specific regions, was the first effect of insulin treatment detected. However, on continuous exposure to a low dose of insulin (0.2 U/ml) the RNA content of the brain was reduced before the DN

ISSN:0040-3709    

DOI:10.1002/tera.1420040409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractAn abnormal umbilical vein that terminated in the right atrium, which was described by Mende in 1826, is considered to be an example of persistence of the right umbilical vein in man. A similar abnormality has been found in rat fetuses following the administration of certain teratogens to females during pregnancy.

ISSN:0040-3709    

DOI:10.1002/tera.1420040410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

ISSN:0040-3709    

DOI:10.1002/tera.1420040411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY