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Journal of Mammalian Evolution - Late Pleistocene cave lions are one of the most iconic species of Northern Hemisphere Quaternary taphocoenoses. Despite their often-scarce record in cave...  相似文献   
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Journal of Mammalian Evolution - The late Miocene was a period of great radiation for the subfamily Caninae in North America. During this time, the early taxa of the two tribes of this subfamily,...  相似文献   
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Doklady Biological Sciences - A mandible fragment and four isolated teeth of the fossil foxes, Vulpes alopecoides (Del Campana, 1913), Vulpes cf. vulpes (Linnaeus, 1758) and Vulpes sp., are...  相似文献   
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Joubert's syndrome (JS) is an autosomal recessive disorder, which is characterised by a variable combination of central nervous, respiratory and eye anomalies. We review the clinical characteristics of the 53 so far reported children with Joubert's syndrome, stressing the importance of recognising the syndrome in the neonatal period, in order that specific and effective therapeutic measures be started as soon as possible.  相似文献   
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The issue of adverse human health effects due to exposure to electromagnetic fields is still unclear, and congenital anomalies are among the outcomes that have been inconsistently associated with such exposure. We conducted a population-based, case-control study to examine the risk of congenital anomalies associated with maternal exposure to magnetic fields (MF) from high-voltage power lines during pregnancy in a community in northern Italy. We identified 228 cases of congenital malformations diagnosed in live births, stillbirths, and induced abortions among women living in the municipality of Reggio Emilia during the period 1998-2006, and a reference group of healthy newborns was matched for year of birth, maternal age, and hospital of birth. We identified maternal residence during early pregnancy and used Geographic Information System to determine whether the residences were within geocoded corridors with MF ≥0.1 μT near high-voltage power lines, then calculated the relative risk (RR) of congenital anomalies associated with maternal exposure. One case and 5 control mothers were classified as exposed, and the RR associated with MF ≥0.1 μT was 0.2 (95% CI: 0.0-2.0) after adjusting for maternal education. While small or moderate effects may have gone undetected due to low statistical power, the results of this study overall do not provide support for major effects of a teratogenic risk due to exposure to MF during early pregnancy.  相似文献   
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The aim of this study was to investigate the immunohistochemical expression of p53 and Ki67 in colorectal adenomas in order to clarify their significance as indicators of malignancy and development of new polyps. Seventy-eight polyps were removed from 51 patients and examined. Twenty-nine patients (56.9%) had adenomas with low-grade atypia (13 of them developed new polyps at 3-year follow-up) and 22 (43.1%) had adenomas with high-grade atypia (6 of them developed new polyps at 3-year follow-up). We tested the association between p53 and Ki67 expression and various clinicopathological variables, and regression analysis was performed to identify the risk factors for malignancy and development of new adenomas. A significant correlation between the grade of atypia and p53 immunoreactivity was observed. Ki67 expression was not related to atypia and no correlation was found between p53 and Ki67 immunoreactivity. Regression analysis showed that size (p=0.0002) and p53 staining (p=0.0111) were the selected factors related to malignant transformation, whereas the number of synchronous primary polyps emerged as the only predictive factor of development of new adenomas, although without statistical significance. The expression of biological markers may be in future added to the currently examined features of polyps; however, further studies are needed to better define their predictive value.  相似文献   
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The molar ratio method presented by Acta Zoologica (98, 2016, 292) is a valid way to estimate the dietary differences between extant subspecies of the raccoon dog genus, Nyctereutes. Particularly, higher values of the molar ratio implies more omnivous diet than lower ones. With the same technique is possible to infer variations in the diet of extinct species. For the two Plio-Pleistocene fossil species Nyctereutes sinensis and Nyctereutes megamastoides, the authors estimate a more carnivorous diet for the latter in comparison to the former that has much higher values. This fact contrast with the morphological features of these two highly comparable species, often considered as morphotypes of the same species. Thanks to the revision of a large sample of N. sinensis from Chinese localities of the Yushe Basin (Shanxi Province), new scores for this species have been calculated. The results presented here confirms a strong adaptation to an omnivorous diet, as emerged from morphofunctional evidence in recent literature.  相似文献   
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