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131.
Adverse effects of prenatal methimazole exposure.   总被引:3,自引:0,他引:3  
BACKGROUND: A specific phenotype of methimazole (MMI) induced malformations has recently been postulated. MMI embryopathy is characterized by minor dysmorphic features, choanal atresia and/or esophageal atresia, growth retardation, and developmental delay. METHODS: We prospectively studied the outcome of pregnancy in 241 women counseled by 10 Teratology Information Services (TIS) of the European Network of Teratology Information Services (ENTIS) because of MMI exposure, and compared them with those of 1,089 pregnant women referred to TIS because of exposure to nonteratogenic drugs (control group). Information was obtained by mail or telephone interview. RESULTS: There was no increase in the general rate of major anomalies or of spontaneous or induced abortions in the MMI-exposed group in comparison with the control group. Two newborns were affected with one of the major malformations that are part of the postulated embryopathy. CONCLUSIONS: The results of this study indicate that choanal as well as esophageal atresia may have a higher incidence than expected in fetuses exposed to MMI between 3 and 7 gestational weeks. Until further data are available, thyrotoxicosis should be treated with propylthiouracil, as it is apparently safer for use during the fertile period.  相似文献   
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Subcellular membrane fractions were prepared from the salt glands of osmotically-stressed ducklings. Two fractions were characterized biochemically with respect to (Na+ + K+)-ATPase, alkaline phosphodiesterase I, succinate dehydrogenase, esterase, and galactosyltransferase activities and immunochemically with respect to (Na+ + K+)-ATPase. The ratios of the estimates of the (Na+ + K+)-ATPase contents obtained biochemically and immunochemically from the two fractions differed by more than 2 X. The results are consistent with the presence of at least two molecular species of (Na+ + K+)-ATPase, unevenly distributed between the two fractions.  相似文献   
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To control some aspects of Lipid metabolism in G-6-PD defective subjects, are evaluated the haematic levels of Cholesterol, Tri glycerides, total Lipids and Lipoproteins. There is no significative difference between enzymopathic and normal control subjects.  相似文献   
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40Ar/39Ar dating of tuffs and mafic lavas, tephra geochemistry, and paleomagnetic reversal stratigraphy have been used to establish the chronostratigraphy of the Pliocene hominid-bearing fossiliferous succession at Woranso-Mille, a paleontological study area in the western part of the central Afar region of Ethiopia. The succession in the northwestern part of the study area ranges in 40Ar/39Ar age from 3.82-3.570 Ma, encompassed by paleomagnetic subchron C2Ar (4.187-3.596 Ma). One of the major tuff units, locally named the Kilaytoli tuff, is correlative on the basis of age and geochemistry to the Lokochot Tuff of the Turkana Basin. A hominid partial skeleton (KSD-VP-1) was found in strata whose precise stratigraphic position and age is still under investigation, but is believed to correspond to the later part of this interval. Woranso-Mille fills a significant gap in the fossil record of northeastern Africa at the time of the lower to middle Pliocene transition, when many extant species lineages of African fauna were established.  相似文献   
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The phylogenetic relationship between Australopithecus anamensis and Australopithecus afarensis has been hypothesized as ancestor‐descendant. However, the weakest part of this hypothesis has been the absence of fossil samples between 3.6 and 3.9 million years ago. Here we describe new fossil specimens from the Woranso‐Mille site in Ethiopia that are directly relevant to this issue. They derive from sediments chronometrically dated to 3.57–3.8 million years ago. The new fossil specimens are largely isolated teeth, partial mandibles, and maxillae, and some postcranial fragments. However, they shed some light on the relationships between Au. anamensis and Au. afarensis. The dental morphology shows closer affinity with Au. anamensis from Allia Bay/Kanapoi (Kenya) and Asa Issie (Ethiopia) than with Au. afarensis from Hadar (Ethiopia). However, they are intermediate in dental and mandibular morphology between Au. anamensis and the older Au. afarensis material from Laetoli. The new fossils lend strong support to the hypothesized ancestor‐descendant relationship between these two early Australopithecus species. The Woranso‐Mille hominids cannot be unequivocally assigned to either taxon due to their dental morphological intermediacy. This could be an indication that the Kanapoi, Allia Bay, and Asa Issie Au. anamensis is the primitive form of Au. afarensis at Hadar with the Laetoli and Woranso‐Mille populations sampling a mosaic of morphological features from both ends. It is particularly difficult to draw a line between Au. anamensis and Au. afarensis in light of the new discoveries from Woranso‐Mille. The morphology provides no evidence that Au. afarensis and Au. anamensis represent distinct taxa. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
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