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511.
A. Sirkka T. Immonen George Varughese Wolfgang H. Pfeiffer Abdul Mujeeb-Kazi 《Euphytica》1992,65(3):203-210
Summary Crossability of wheat and rye was investigated during thirteen crop cycles in two contrasting locations to 1) evaluate tetraploid and hexaploid wheat parents in crosses with rye, 2) identify genotypes with high crossability and 3) assess the impact of environment on seed development. The majority of the tetraploid wheats crossed with rye had seed set around 20%, but very low embryo viability. Several wheat genotypes with seed set above 50% were identified. The hexaploid wheats crossed with rye showed poor seed set, but plant recovery was relatively high. The majority of the hexaploid wheats with highest seed set (20–30%) were from China. The results suggest differences in crossability between the rye populations, and wheat species by rye interactions. The crossability of the tetraploid and hexaploid wheats was affected by climate in the two locations. 相似文献
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O'Doherty A Ruf S Mulligan C Hildreth V Errington ML Cooke S Sesay A Modino S Vanes L Hernandez D Linehan JM Sharpe PT Brandner S Bliss TV Henderson DJ Nizetic D Tybulewicz VL Fisher EM 《Science (New York, N.Y.)》2005,309(5743):2033-2037
Aneuploidies are common chromosomal defects that result in growth and developmental deficits and high levels of lethality in humans. To gain insight into the biology of aneuploidies, we manipulated mouse embryonic stem cells and generated a trans-species aneuploid mouse line that stably transmits a freely segregating, almost complete human chromosome 21 (Hsa21). This "transchromosomic" mouse line, Tc1, is a model of trisomy 21, which manifests as Down syndrome (DS) in humans, and has phenotypic alterations in behavior, synaptic plasticity, cerebellar neuronal number, heart development, and mandible size that relate to human DS. Transchromosomic mouse lines such as Tc1 may represent useful genetic tools for dissecting other human aneuploidies. 相似文献
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Lies Durnez Harrison Sadiki Abdul Katakweba Robert R. Machang’u Rudovik R. Kazwala Herwig Leirs Françoise Portaels 《Tropical animal health and production》2009,41(8):1653-1659
A study was conducted to determine the prevalence of Mycobacterium bovis-infection and atypical mycobacterioses in different cattle herd management systems in and around Morogoro, Tanzania. Between
April and June 2005, a total of 728 bovines from 49 herds were tested for M. bovis-infection and atypical mycobacterioses. Milk samples were taken from tuberculin positive animals and analysed for the presence
of mycobacteria. Total prevalences of 2.5% and 10.1% were found for M. bovis-infection and atypical mycobacterioses respectively, with more M. bovis-infection in cattle in the extensive management system and more atypical mycobacterioses in cattle in the intensive management
system. From 8 out of 42 milk samples (19%) atypical mycobacteria were cultured. A higher prevalence of M. bovis-infection in the extensive sector could be due to several factors. In addition, such high prevalence puts herd owners and
their families at risk for BTB. Therefore control of BTB, as well as education of cattle owners is important, especially in
the extensive sector. 相似文献
516.
Immune responses of whiteleg shrimp,Litopenaeus vannamei (Boone, 1931), to bacterially expressed dsRNA specific to VP28 gene of white spot syndrome virus
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G Taju N Madan S Abdul Majeed T Raj Kumar S Thamizhvanan S K Otta A S Sahul Hameed 《Journal of fish diseases》2015,38(5):451-465
In this study, dsRNA specific to VP28 gene of white spot syndrome virus (WSSV) of shrimp was synthesized in Escherichia coli in large scale and studied the immune response of shrimp to dsRNA‐VP28. The haematological parameters such as clotting time and total haemocytes counts, and immunological parameters such as prophenoloxidase (proPO), superoxide dismutase (SOD), superoxide anion (SOA) and malondialdehyde content, as well as the mRNA expression of ten immune‐related genes were examined to estimate the effect of dsRNA‐VP28 on the innate immunity of Litopenaeus vannamei. The activities of proPO, SOA and SOD significantly increased in haemocyte after dsRNA‐VP28 treatment, whereas MDA content did not change significantly. Among the ten immune‐related genes examined, only the mRNA expression of proPO, cMnSOD, haemocyanin, crustin, BGBP, lipopolysaccharides (LPs), lectin and lysozyme in haemocytes, gill and hepatopancreas of L. vannamei, was significantly upregulated at 12 h after dsRNA‐VP28 treatment, while no significant expression changes were observed in Toll receptor and tumour receptor genes. The increase of proPO and SOD activities, and SOA level and mRNA expression level of proPO, cMnSOD, haemocyanin, crustin, BGBP, LPs, lectin and lysozyme after dsRNA‐VP28 stimulation indicate that these immune‐related genes were involved in dsRNA‐VP28‐induced innate immunity in shrimp. 相似文献
517.
Sayma Akhter Md. Abdul Halim Md. Shawkat Islam Sohel Swapan Kumar Sarker Mohammad Shaheed Hossain Chowdhury Sanjay Saha Sonet 《林业研究》2008,19(1):72-78
This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and using patterns for hair care, facial treatments and body care, were summarized in 13 tables. This paper accumulate the scattered knowledge regarding the use of plants in beauty-care in Bangladesh, to draw the extent of use of NTFPs in health care and to record the knowledge for assessing the possibilities of further implementation in herbal cosmetics industries. The structured knowledge can be used in policy making process for sustainable management of these valuable NTFPs leading to the conservation of the country's biological diversity. It is suggested that intensive field level research is necessary for securing sustainability of NTFPs. 相似文献