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排序方式: 共有494条查询结果,搜索用时 15 毫秒
1.
S Kwiatkowski E Kwiatkowska R Czajka K Ciechanowski K Kedzierska J Bober R Rzepka E Golembiewska D Chlubek 《Hypertension in pregnancy》2006,25(1):37-46
BACKGROUND: Hypertension that develops after 20 gestational weeks and is defined as pregnancy-induced hypertension (PIH). The main cause of PIH is vasoconstriction and the thickening of vascular media, which decreases vascular capacity and increases peripheral resistance. One of the theories postulated to explain this phenomenon is that a transmembrane sodium transport disorder causes an increase in intracellular sodium concentration. In the latest literature, special attention is paid to the role of the increased intracellular sodium concentration in the pathogenesis of essential hypertension (EH). One of the best documented phenotypes for EH is the increased activity of the sodium-proton exchanger (NHE). The aim of this study was to assess if increased NHE activity could be the mechanism responsible for the development of PIH. SUBJECTS AND METHODS: The study included 30 women: 10 pregnant women with PIH after gestational week 30, 10 women with physiological pregnancy after 30 gestational weeks, and 10 healthy non-pregnant women. NHE activity was determined according to Orlov's method as amiloride-sensitive H(+) efflux from acid-loaded cells. RESULTS: The NHE activity in the group of women with PIH was significantly higher than that in women with physiological pregnancy: 10.09 +/- 1.65 vs. 6.81 +/- 2.3 mmol/L RBC/h (p < 0.049) and in the group of non-pregnant women: 10.09 +/- 1.65 vs. 7.56 +/- 1.66 mmol/L RBC/h (p < 0.029). Erythrocyte NHE activity did not differ in the group of women with physiological pregnancy and in the group of non-pregnant women. CONCLUSION: These results seem to suggest that erythrocyte NHE activity is elevated in PIH pregnancies. 相似文献
2.
Alexander S. Graphodatsky Polina L. Perelman Natalya V. Sokolovskaya Violetta R. Beklemisheva Natalya A. Serdukova Gauthier Dobigny Stephen J. O’Brien Malcolm A. Ferguson-Smith Fengtang Yang 《Chromosome research》2008,16(1):129-143
Canid species (dogs and foxes) have highly rearranged karyotypes and thus represent a challenge for conventional comparative
cytogenetic studies. Among them, the domestic dog is one of the best-mapped species in mammals, constituting an ideal reference
genome for comparative genomic study. Here we report the results of genome-wide comparative mapping of dog chromosome-specific
probes onto chromosomes of the dhole, fennec fox, and gray fox, as well as the mapping of red fox chromosome-specific probes
onto chromosomes of the corsac fox. We also present an integrated comparative chromosome map between the species studied here
and all canids studied previously. The integrated map demonstrates an extensive conservation of whole chromosome arms across
different canid species. In addition, we have generated a comprehensive genome phylogeny for the Canidae on the basis of the
chromosome rearrangements revealed by comparative painting. This genome phylogeny has provided new insights into the karyotypic
relationships among the canids. Our results, together with published data, allow the formulation of a likely Canidae ancestral
karyotype (CAK, 2n = 82), and reveal that at least 6–24 chromosomal fission/fusion events are needed to convert the CAK karyotype
to that of the modern canids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Svetlana A. Romanenko Natalia A. Sitnikova Natalya A. Serdukova Polina L. Perelman Nadezhda V. Rubtsova Irina Yu. Bakloushinskaya Elena A. Lyapunova Walter Just Malcolm A. Ferguson-Smith Fengtang Yang Alexander S. Graphodatsky 《Chromosome research》2007,15(7):891-897
Using cross-species chromosome painting, we have carried out a comprehensive comparison of the karyotypes of two Ellobius species with unusual sex determination systems: the Transcaucasian mole vole, Ellobius lutescens (2n = 17, X in both sexes), and the northern mole vole, Ellobius talpinus (2n = 54, XX in both sexes). Both Ellobius species have highly rearranged karyotypes. The chromosomal paints from the field vole (Microtus agrestis) detected, in total, 34 and 32 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. No difference in hybridization pattern of the X paint (as well as Y paint) probes on male and female
chromosomes was discovered. The set of golden hamster (Mesocricetus auratus) chromosomal painting probes revealed 44 and 43 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. A comparative chromosome map was established based on the results of cross-species chromosome painting
and a hypothetical ancestral Ellobius karyotype was reconstructed. A considerable number of rearrangements were detected; 31 and 7 fusion/fission rearrangements
differentiated the karyotypes of E. lutescens and E. talpinus from the ancestral Ellobius karyotype. It seems that inversions have played a minor role in the genome evolution of these Ellobius species. 相似文献
4.
Lactation and breast cancer. Evidence for a negative association in premenopausal women 总被引:8,自引:0,他引:8
The authors report a case-control study of breast cancer based on an analysis of data collected by interview between the years 1957-1965 from women residing in the communities of Buffalo and Kenmore, New York. Prior reproductive factors, including a detailed lactation history, were examined for 453 white females with breast cancer and 1,365 white females without breast cancer who were selected randomly from the population of Buffalo and Kenmore. There is evidence of a negative association between length of nursing and breast cancer risk in premenopausal women which is not seen in the postmenopausal women. This apparent "protective" effect of lactation persists after statistical control for the potential confounding factors of age, parity, age at first pregnancy, age at menarche, and education. Cases are more likely than controls to have reported unsuccessful lactations due to "insufficient milk." The findings of this study, in conjunction with the authors' review of previously published studies that have examined prior lactation as related to breast cancer risk, suggest that there may be an independent negative association between nursing and subsequent breast cancer risk in premenopausal women. Whether this means that breast feeding is protective or that some women who are unsuccessful at lactation are at increased risk for subsequent breast cancer is not clear. A detailed reanalysis of existing data and more careful attention to detailed prior breast function/dysfunction in future studies are recommended. 相似文献
5.
Nima Milani-Nejad Polina Rzepka Matthew J. Zirwas Jessica Kaffenberger 《The Journal of clinical and aesthetic dermatology》2021,14(4):36
Bullous pemphigoid is an autoimmune condition whereby the immune system forms antibodies that target the skin, resulting in the formation of blisters in a generalized and symmetric pattern. Localized bullous pemphigoid can occur in special circumstances. Here, we describe two patients that developed localized bullous pemphigoid in one lower extremity following orthopedic surgery. We propose that underlying edema following orthopedic surgery is a potential trigger for localized bullous pemphigoid. 相似文献
6.
Bella Shadur Nathalie Asherie Peter E. Newburger Polina Stepensky 《Pediatric blood & cancer》2019,66(1)
Mutations in the VPS45 gene lead to a severe primary immune deficiency characterized by severe congenital neutropenia and primary myelofibrosis, leading to overwhelming infection and early death. This condition is exceedingly rare with only 16 patients previously reported, including four with successful hematopoietic stem cell transplantation. We review the pathophysiology underlying this condition and detail our approach to treatment, particularly vis‐à‐vis bone marrow transplantation and the challenges of transplanting into a diseased bone marrow niche. We provide an update on the progress of our three previously reported patients, and two additional patients transplanted at our center. 相似文献
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