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111.
N Bressani B di Natale C Pellini F Triulzi G Scotti G Chiumello 《Hormone research》1990,34(5-6):189-192
Fifty-seven children with growth hormone deficiency and 15 healthy age-matched controls were studied by magnetic resonance imaging (MRI). Of the patients, 36 (63%) had isolated GH deficiency (IGHD) and 21 (37%) multiple pituitary hormone deficiency (MPHD). MRI studies showed a marked reduction in pituitary volume in all patients in comparison with normal controls. Moreover, a striking morphological abnormality with the apparent absence of the pituitary stalk and an ectopic posterior pituitary lobe was detected in 34 of the patients (59%). This pituitary stalk abnormality was detected in 95% of the MPHD patients and in 39% of the IGHD patients. All but one of the patients with a normal pituitary stalk had IGHD. Endocrine evaluation showed no correlation with MRI data: in particular patients with an apparent anatomical interruption of the hypothalamic-pituitary axis showed a variety of patterns of hormonal responses. In conclusion, our study shows a high frequency of hypothalamic-pituitary anomalies in patients with GH deficiency, particularly related with MPHD. However, further studies are needed to improve our understanding of the relationship between MRI and endocrine data. 相似文献
112.
M. J. Benton E. Cook D. Grigorescu E. Popa E. Talldi 《Palaeogeography, Palaeoclimatology, Palaeoecology》1997,130(1-4):275-292
The bauxite mine at Cornet near Oradea in northwestern Romania produced thousands of bones in an excavation in 1978, mainly from ornithopod dinosaurs and rarer pterosaurs. Bird specimens reported previously from this fauna are equivocal. The fossils are disarticulated bones in good condition which occur highly concentrated in lenses within bauxite clays, which are dated as Berriasian (earliest Cretaceous). The bauxite represents detrital material washed into deep fissures and caves formed within a karst of uplifted Tithonian (latest Jurassic) marine limestones. The bones are generally uniform in size and shape, and they are abraded, evidence for considerable transport and for winnowing of the deposit. The area was one of several islands on the northern shore of Tethys, and it was inundated by the sea later in the Early Cretaceous. There is evidence for insular adaptations in the dinosaur faunas. The ornithopod dinosaurs may include several taxa, but they are smaller on average than an assemblage of typical Wealden ornithopods, perhaps because of dwarfing on the island. In addition, sauropods are absent and theropods are barely represented in the fauna. The fauna is geographically significant since it shows relationships with western Europe and with Asia. 相似文献
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Lászlo Bátkai Mihály Nográdi Loránd Farkas Lászlo Feuer István Horváth 《Archives of microbiology》1973,90(2):165-166
Summary The ability of various strains of fungi to transform isoflavones was studied. It was found that demethylation of 7-methoxyisoflavon is effected by Penicillium cyclopium. 相似文献
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CorrespondenceProf。E。Tremblay,80055 Por协d(1饭山)殆廿恤todi Entomologia娜护aria血11,U川ve邝就应di NaPoll, Int找峨Uctfon In a stUdy recentlys认址ted on the Par创红tojd comPlex of the large filber七即hidCO,百lobiuma”ella”aes七hrk.(V触名运苗,1953),several明estionse们ne rged (T。Huddieston and P .Star夕扭琢ter招)on the记elltity of a Pra。旅sP。己esw址ch seerr‘to be one of the main parasitoids of the aPhid in severatre廊onsoflt目y。Th贻led us to ar时xar苗川币on of theBr节也hM山eu们。… 相似文献
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William T. Garside J. Ricardo Loret de Mola Jennifer A. Bucci Richard W. Tureck Susan Heyner 《Molecular reproduction and development》1997,47(1):99-104
Zona pellucida thickness was measured daily in zygotes and cleavage stage embryos. Measurements were performed on a Nikon inverted microscope equipped with Hoffman modulation optics, using an ocular micrometer. Zona thickness of each zygote/embryo was measured four times, the zygote/embryo was then “rolled over,” and four more measurements were repeated for a total of eight. The zygotes/embryos were photographed daily and the measurements repeated on the prints. Subsequently, the mean zona thickness for each stage was calculated. A total of 81 patients (mean age 33.8 ± 4.2) participated in the study. A total of 427 embryos were evaluated. Categorical data differences between groups were evaluated by ANOVA and multiple linear regression. For nominal data, the Kruskal-Wallis test was applied; when P < 0.05 the differences were considered to be significant. We found that the average zona thickness on day 1 of in vitro culture was 17.7 ± 0.14 μm; 16.3 ± 0.14 μm on day 2 and 14.9 ± 0.14 μm on day 3 (P < .0001). When the zona thickness was analyzed in relation to the number of blastomeres on day 3 of culture, there was a highly significant correlation with blastomere number (P < .0001). Similarly, there was a highly significant correlation with embryo grade (P < .005) and fragmentation (P < .001). The data were also analyzed for embryos transferred that resulted in a successful pregnancy, revealing that embryos in a pregnancy cycle had significantly thinner zonae pellucidae (P < .0001), when compared to embryos that were not transferred or from nonconceptual cycles. The average zona thickness also decreased with age, and was most apparent after 35 years. Changes in zona thickness correlated with the number of blastomeres, grade, fragmentation, age and were more evident in embryos transferred from cycles resulting in successful pregnancies. Therefore, zona pellucida measurements should be included in the overall assessment of embryo quality, since this information may be useful in the selection of optimal embryos for transfer. Mol. Reprod. Dev. 47:99–104, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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