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361.
Dehydrated hereditary stomatocytosis (DHS) is a rare congenital hemolytic anemia. We observed that some patients had presented with different prenatal or perinatal forms of edema in some kindreds. Within weeks or months after birth, these exhibited a spontaneous, complete and definitive resorption. We assumed that some DHS patients, who were born without edema before ultrasound was available, might nonetheless have exhibited this during the prenatal period. The present report follows up the first pregnancy in a woman with overt DHS, but not herself having a known history of perinatal effusions. Ultrasound revealed that the fetus displayed ascites that disappeared prior to birth. The neonate had DHS. Prenatal edema must therefore be more frequent in DHS than known until now. DHS is another cause of prenatal edema to be considered in the differential diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Objective This study was conducted to evaluate the major demographic details, diagnostical and clinical features, as well as the risk of recurrence of cases with the major types of neural tube defects (NTD). We also examined the efficiency of ultrasonography based on autopsy examinations during 26 years. Methods The investigations were made into the sample of 743 NTD diagnosed between 1 January 1976 and 31 December 2002. A computerized database was used to sum up the available information about the individual cases; in addition to surveying the couples' major demographic details, we also had the opportunity to collect detailed information about the history, diagnostics (ultrasound) and outcome of the pregnancies as well as the results of the autopsies during the investigation. Results In the 743 cases of NTD, maternal and paternal median ages turned out to be 23.7 years (±5.22 years) and 28.7 years (±5.81 years), respectively. The male:female ratio was 0.78. Comparable samples of anencephaly and spina bifida allowed for the conclusion that a positive genetic history was equally often found while a positive obstetrical history was almost twice as common in anencephaly. The sensitivity of the maternal serum-alpha fetoprotein (AFP) screening test is the highest in anencephaly and lowest in encephalocele. While the majority of cases of anencephaly were diagnosed before the 24th gestational week, examples of diagnosing spina bifida and encephalocele at a later time could also be found. Among the associated malformations other than those of the central nervous system special mentioning should be made of fetal pyelectasia, cleft palate as well as diaphragmatic herniation. No pathological karyotypes were found in association with encephalocele or spina bifida, but anencephaly was accompanied with trisomy 21 and trisomy 18 in one case each. Anencephaly was found to have the highest risk of recurrence in both nervous system malformations and malformations other than those of the nervous system. Sonography proved to be the most reliable method in cases of enecephalocele. Conclusion The respective median values of maternal and paternal age show that aetas has no role in the occurrence of NTDs. NTDs are more common among girls. Positive genetic, obstetrical and medical findings are of great importance in the incidence of NTDs. Although reliable to only a limited extent, maternal serum-AFP tests are considered to be useful and necessary in screening NTDs, while sonography is the gold standard method in recognizing these frequent malformations. The knowledge of the eventual associated malformations is mainly important in certain cases of spina bifida, which may also yield a good post-natal prognosis. Our data obtained from the sample of 26 years also confirm that the periconceptional administration of folic acid reduces the incidence and risk of recurrence of NTDs. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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Environmental Science and Pollution Research - In the scope of the study, the protective effect of hesperidin (HES), a flavanone glycoside, was investigated against sodium arsenite (NaAsO2, SA)...  相似文献   
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The measurement of chromium and yttrium concentration could give a chance to detect 5–10 times less chromium contamination in soil by using the yttrium normalisation method. The principle of the method is the following: elements such as chromium and yttrium exist naturally in the soil in a strongly bonded form. Therefore, in a noncontaminated area there should be a close correlation between the yttrium and chromium concentrations. If the measured Cr concentration in a sample is not on the Cr–Y trend line then the distance of plotted point from the line indicates the amount of anthropogenic chromium. Anthropogenic chromium can be detected only in the case when the contamination does not contain yttrium. This theory was tested in an agricultural–toxicological field experiment where Cr(VI) was added to the soil. Applying the yttrium normalisation method a much smaller anthropogenic effect was detected than by other evaluation methods.  相似文献   
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It is rare to find a true predator that repeatedly and routinely kills prey larger than itself. A solitary specialised ant-eating spider of the genus Zodarion can capture a relatively giant prey. We studied the trophic niche of this spider species and investigated its adaptations (behavioural and venomic) that are used to capture ants. We found that the spider captures mainly polymorphic Messor arenarius ants. Adult female spiders captured large morphs while tiny juveniles captured smaller morphs, yet in both cases ants were giant in comparison with spider size. All specimens used an effective prey capture strategy that protected them from ant retaliation. Juvenile and adult spiders were able to paralyse their prey using a single bite. The venom glands of adults were more than 50 times larger than those of juvenile spiders, but the paralysis latency of juveniles was 1.5 times longer. This suggests that this spider species possesses very potent venom already at the juvenile stage. Comparison of the venom composition between juvenile and adult spiders did not reveal significant differences. We discovered here that specialised capture combined with very effective venom enables the capture of giant prey.  相似文献   
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Food and Environmental Virology - Concentration of viruses in water is necessary for detection and quantification of the viruses present, in order to evaluate microbiological barriers in water...  相似文献   
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