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61.
孕产妇孕期保健及孕产妇健康对促进安全分娩和优生优育起着十分重要的作用,随着我国孕产妇保健工作的进一步完善及国家二胎政策的实施,现代临床医学所倡导的优生优育的观念已逐渐被社会广泛认可。然而,我国少数民族地区多有经济落后、地理位置偏僻、思想观念陈旧等问题,导致我国少数民族孕产妇孕期保健水平还比较低下,孕产妇健康状况有待改善。为预防少数民族地区出生缺陷,降低出生缺陷率,提高优生率,提高少数民族地区出生人口素质,通过完善医疗制度,改善医疗环境,合理营养干预及加强家庭访视等相关健康教育促进孕期保健,提高孕前检查的依从性,实现优生,孕产期健康教育可以降低整个孕期出现的危险因素,本文对我国少数民族的孕产妇孕期保健及健康做一综述。  相似文献   
62.
Members of the Chenopodiaceae are the most dominant elements in the central Asian desert. The different genera and species within this family are common in desert vegetation types. Should it prove possible to link pollen types in this family to specific desert vegetation, it would be feasible to trace vegetation successions in the geological past. Nevertheless, the morphological similarity of pollen grains in the Chenopodiaceae rarely permits identification at the generic level. Although some pollen classifications of Chenopodiaceae have been proposed, none of them tried to link pollen types to specific desert vegetation types in order to explore their ecological significance. Based on the pollen morphological characters of 13 genera and 24 species within the Chenopodiaceae of eastern central Asia, we provide a new pollen classification of this family with six pollen types and link them to those plant communities dominated by Chenopodiaceae, for example, temperate dwarf semi‐arboreal desert (Haloxylon type), temperate succulent halophytic dwarf semi‐shrubby desert (Suaeda, Kalidium, and Atriplex types), temperate annual graminoid desert (Kalidium type), temperate semi‐shrubby and dwarf semi‐shrubby desert (Kalidium, Iljini, and Haloxylon types), and alpine cushion dwarf semi‐shrubby desert (Krascheninnikovia type). These findings represent a new approach for detecting specific desert vegetation types and deciphering ecosystem evolution in eastern central Asia.  相似文献   
63.
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a genetic cardiac muscle disease that accounts for approximately 30% sudden cardiac death in young adults. The Ser358Leu mutation of transmembrane protein 43 (TMEM43) was commonly identified in the patients of highly lethal and fully penetrant ARVD subtype, ARVD5. Here, we generated TMEM43 S358L mouse to explore the underlying mechanism. This mouse strain showed the classic pathologies of ARVD patients, including structural abnormalities and cardiac fibrofatty. TMEM43 S358L mutation led to hyper-activated nuclear factor κB (NF-κB) activation in heart tissues and primary cardiomyocyte cells. Importantly, this hyper activation of NF-κB directly drove the expression of pro-fibrotic gene, transforming growth factor beta (TGFβ1), and enhanced downstream signal, indicating that TMEM43 S358L mutation up-regulates NF-κB-TGFβ signal cascade during ARVD cardiac fibrosis. Our study partially reveals the regulatory mechanism of ARVD development.  相似文献   
64.
c-Abl是非受体酪氨酸激酶,它在细胞内被一些基因毒性的、氧化的及其它形式的压力所激活。目前研究证明:应用标记的c-Abl发现其在细胞内可以相互形成同源二聚体,并且一分子c-Abl的N末端区域与相应的另一分子的C末端相互作用形成二聚体。实验进一步表明: cAbl SH3 结构域结合到另一c-Abl 分子富含脯氨酸的C-末端约958-982氨基酸区域。如果去除c-Abl 富含脯氨酸的结构域,就会阻止二聚体的形成。这些结果首先证实了c-Abl在细胞内可以相互形成同源二聚体,并暗示着二聚体的形成可能影响着c-Abl活性的调节。  相似文献   
65.
Stripe rust is a devastating fungal disease of wheat worldwide which is primarily caused by Puccinia striiformis f. sp tritici. Transgenic wheat (Triticum aestivum L.) expressing rice class chitinase gene RC24 were developed by particle bombardment of immature embryos and tested for resistance to Puccinia striiformis f.sp tritici. under greenhouse and field conditions. Putative transformants were selected on kanamycin-containing media. Polymease chain reaction indicated that RC24 was transferred into 17 transformants obtained from bombardment of 1,684 immature embryos. Integration of RC24 was confirmed by Southern blot with a RC24-labeled probe and expression of RC24 was verified by RT-PCR. Nine transgenic T1 lines exhibited enhanced resistance to stripe rust infection with lines XN8 and BF4 showing the highest level of resistance. Southern blot hybridization confirmed the stable inheritance of RC24 in transgenic T1 plants. Resistance to stripe rust in transgenic T2 and T3 XN8 and BF4 plants was confirmed over two consecutive years in the field. Increased yield (27–36 %) was recorded for transgenic T2 and T3 XN8 and BF4 plants compared to controls. These results suggest that rice class I chitinase RC24 can be used to engineer stripe rust resistance in wheat.  相似文献   
66.
Plasmodium falciparum histidine-rich protein 2 (PfHRP2) has been suggested to be an initiator of the polymerization of heme, which is produced as by-product on the digestion of hemoglobin, and a promoter of the H(2)O(2)-induced degradation of heme in food vacuoles of the malarial parasite. In this work, we have designed PfHRP2 model peptides, R18 and R27 (18 and 27 residues, respectively), and used them for optical and electron spin resonance spectroscopic measurements to confirm that the axial ligands of the heme-PfHRP2 complex are the nitrogenous donors derived from the imidazole moieties of histidine residues of PfHRP2. In addition, we revealed that the affinities of R18 and R27 for heme (K(d) = 2.21 x 10(-6) M and 0.71 x 10(-6) M, respectively) might be as high as that of PfHRP2 (K(d) = 0.94 x 10(-6) M). The R27 peptide can remove heme from membrane-intercalated heme and inhibit heme-induced hemolysis. Therefore, we suggest another function of PfHRP2: it may play an important role in the neutralization of toxic heme in the parasite cytoplasm and infected erythrocytes by removing heme from heme-bound membranes or reducing heme-induced hemolysis.  相似文献   
67.
68.
Homoploid hybrid speciation, the origin of a hybrid species without change in chromosome number, is currently considered to be a rare form of speciation. In the present study, we examined the phylogenetic origin of Hippophaë gyantsensis, a diploid species occurring in the western Qinghai–Tibet Plateau. Some of its morphological and molecular traits suggest a close relationship to H. rhamnoides ssp. yunnanensis while others indicate H. neurocarpa. We conducted phylogenetic analyses of sequence data of two maternally inherited chloroplast (cp) DNA fragments and the bi‐parentally inherited nuclear ribosomal internal transcribed spacer (ITS) from 17 populations of H. gyantsensis, 15 populations of H. rhamnoides ssp. yunnanensis and 27 populations of H. neurocarpa across their distributional ranges, and modelled the niche differentiation of the three taxa. Multiple lines of evidence suggested that H. gyantsensis is a morphologically stable, genetically independent and ecologically distinct species. The inconsistent phylogenetic placements of the H. gyantsensis clade that comprised the dominant cpDNA haplotypes and ITS ribotypes suggested a probable diploid hybrid origin from multiple crosses between H. rhamnoides ssp. yunnanensis and H. neurocarpa. This tentative hypothesis is more parsimonious than alternative explanations according to the data available, although more evidence based on further testing is needed.  相似文献   
69.
Liu X  Guo Z  Ke Z  Wang S  Li Y 《PloS one》2011,6(3):e18429

Background

Anthropogenically-induced climate change can alter the current climatic habitat of non-native species and can have complex effects on potentially invasive species. Predictions of the potential distributions of invasive species under climate change will provide critical information for future conservation and management strategies. Aquatic ecosystems are particularly vulnerable to invasive species and climate change, but the effect of climate change on invasive species distributions has been rather neglected, especially for notorious global invaders.

Methodology/Principal Findings

We used ecological niche models (ENMs) to assess the risks and opportunities that climate change presents for the red swamp crayfish (Procambarus clarkii), which is a worldwide aquatic invasive species. Linking the factors of climate, topography, habitat and human influence, we developed predictive models incorporating both native and non-native distribution data of the crayfish to identify present areas of potential distribution and project the effects of future climate change based on a consensus-forecast approach combining the CCCMA and HADCM3 climate models under two emission scenarios (A2a and B2a) by 2050. The minimum temperature from the coldest month, the human footprint and precipitation of the driest quarter contributed most to the species distribution models. Under both the A2a and B2a scenarios, P. clarkii shifted to higher latitudes in continents of both the northern and southern hemispheres. However, the effect of climate change varied considerately among continents with an expanding potential in Europe and contracting changes in others.

Conclusions/Significance

Our findings are the first to predict the impact of climate change on the future distribution of a globally invasive aquatic species. We confirmed the complexities of the likely effects of climate change on the potential distribution of globally invasive species, and it is extremely important to develop wide-ranging and effective control measures according to predicted geographical shifts and changes.  相似文献   
70.
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