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991.
HUANG Hua LI Yu-sheng JIN Xin WANG Jiang-tao LI Na HUANG Zhen-gui DING Bo-ping 《园艺学报》2015,31(8):1365-1370
AIM: To investigate the effect of rhynchophylline (Rhy) on blood pressure, cardiac hypertrophy and myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Spontaneously hypertensive rats were randomly divided into model group, high dose (10 mg·kg-1·d-1) and low dose (2.5 mg·kg-1·d-1) group of rhynchophylline, captopril group (17.5 mg·kg-1·d-1). Wistar-Kyoto rats were used as normal control. Respectively, systolic blood pressure was measured by tail cuff every 2 weeks. After 10 weeks, heart weight index and left ventricular weight index were calculated. The myocardial hydroxyproline and plasma angiotensin Ⅱ were detected. Moreover, basic myocardial histopathological changes and myocardial collagen fibres were observed by HE staining and Masson staining, respectively. The protein expression of TGF-β1 and Smad3 in the myocardium was measured by the methods of immunohistochemistry and Western blot. RESULTS: Compared with SHR model group, Rhy significantly reduced blood pressure (P<0.05), the levels of HYP in the myocardium (P<0.05) and the levels of AngⅡ in the plasma (P<0.01). The pathological damages of the myocardial tissues and collagen deposition were attenuated. The protein expression of TGF-β1 and Smad3 was significantly reduced by the treatment with Rhy (P<0.01). CONCLUSION: Rhynchophylline reduces blood pressure and adjusts to improve ventricular remodeling of SHR. The mechanism may be involved in the TGF-β1/Smad pathway and reducing AngⅡ content. 相似文献
992.
CHANG Cheng JIN Peng ZHENG Wei KANG Hua-li DENG Meng-yang LI Shuang-fei WU Xiao-jing 《园艺学报》2015,31(1):12-17
AIM: To study the expression of Jagged2/Notch3 signaling molecules in pulmonary vascular wall of pulmonary hypertensive rats induced by monocrotaline. METHODS: SD rats were randomly divided into normal control group (C group,n=15), solvent control group (S group,n=15) and monocrotaline model groups (M group,n=15). The model of pulmonary hypertension was established by a single subcutaneous injection of monocrotaline (50 mg/kg). The rats in S group were given a single subcutaneous injection of the same dose of solvent. After 4 weeks, the pulmonary vascular remodeling was assessed by HE staining, and the mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP) were determined by right heart catheterization. The expression of Jagged2/Notch3/Hes5 molecules in the pulmonary vascular wall was detected by immunohistochemical method and real-time PCR. RESULTS: Compared with S group and C group, the percentage of medial wall thickness of smaller arteries in model group increased significantly (P<0.01). The levels of mPAP and RVSP in M group were significantly higher than those in S group and C groups (P<0.01). The results of real-time PCR showed that the expression of Jagged2, Notch3 and Hes5 was significantly increased in M group compared with S group and C group. The data from immunohistochemical detection indicated that Jagged2 mainly expressed in the intima of small lung artery, Notch3 and Hes5 mainly expressed in the medial smooth muscle cells. Compared with S group and C group, the expression of Jagged2 and Notch3 was significantly increased in the lung small arteries of M group. CONCLUSION: The activation of Jagged2/Notch3 signaling pathway might play an important role in the formation of pulmonary hypertension. 相似文献
993.
994.
Cre/loxP定位重组系统在植物雄不育和杂种优势中的利用研究 总被引:4,自引:0,他引:4
Cre—loxP是来源于噬菌体P1的一种位点特异性重组系统。目前,它已广泛应用于基因功能鉴定,动植物及微生物基因组的修饰以及基因的表达和调控。雄性不育系在杂种优势的利用中具有重要意义。本实验是以Cre—loxP系统调控细胞毒素基因barnase在植物雄性器官发育的特异时期在特异组织表达,从而达到控制植物育性的目的。1.在本实验中,通过PCR方法克隆了解淀粉芽孢杆菌Bacillus amyloliquefaciens的barnase基因,及其抑制因子barstar的DNA序列,同时,构建成功双元表达载体及基因枪转化载体,并已获得经分子险测呈阳性的小麦植株。2.osg6B是来源于水稻花药绒毡层的特异性的启动子,它在小孢子发育的四分体时期至单核花粉期在花药绒毡层中特异启动基因的表达,它具有较为严紧的时空特异性。以osg6B为启动子,构建了一组受控于Cre/loxP位点特异性重组系统的适用于基因枪法转化小麦的载体系统。其中,转不育基因(og6B—barnase)小麦植株生长正常,但开花后,花粉量明显减少,自交不能得到正常种子。进行花粉活力检测发现,转基因小麦大部分花粉表现为败育。花粉离体萌发试验表明,转不育基因小麦的花粉离体萌发率极低,几近败育。说明以osg6B驱动barnase在小麦花药中的表达可以导致雄性不育。3.以osg6B为启动子,构建了一组受控于Cre/loxP的用于控制双子叶植物育性的双元表达载体系统。以转cre基因的烟草作为受体,以含阻断序列的质粒农杆菌进行二次转化。二次转化株营养生长正常,但开花期花器官表现异常。具体表现为花瓣异常开裂或不开裂,花丝变短或粘连,花药提早萎蔫或异常开裂。推测这种现象的出现与启动子的组织特异性或barnase的渗露表达有关。4.二次转化株花粉染色因不同株系出现全部败育、部分不育和多数可育的情况。花粉离体萌发实验也得到了相似的结果。这说明通过筛选,利用Cre/loxP得到完全不育的植物株系是完全可行的。5.获得了9个barnase的突变体,初步推测第十四位氨基酸及第八十位氨基酸与核糖核酸酶活性有关。同时,发现barnase的第316位核苷酸序列为易突变位点,自然发生的突变多插入一个C,从而产生终止位点的改变。这或许会为今后barnase的克隆与利用提供一些参考。 相似文献
995.
Jerzy Drzewiecki 《Euphytica》2001,119(3):279-287
Wheat-rye translocation line (2BS/2RL) has been developed for resistance to biotype L of Hessian fly and agronomically useful
traits. AFLP analysis using 64 primer pairs was conducted in order to identify 2RL-specific polymorphisms between “Coker 797”
(non-2RL), near-isogenic line (NIL) carrying 2RL, and “Hamlet”. Nine primer combinations identified twelve reproducible polymorphic
fragments in the NIL carrying 2RL. These twelve fragments were cloned and sequenced with an aim towards converting AFLP markers
into sequence tagged sites (STS). A comparison of the 12 sequences with non-redundant accessions in the NCBI database using
the BLAST search option indicated that one fragment of approximately 200 bp in length (amplified using primer combination
E+AAC / M+CTA) was highly homologous with the rye-specific repetitive sequence R173-1 and Wis-2-lA, a retrotransposon-like
element in wheat. Two STS primers (SJ07 and SJ09) out of twelve STS primer sets enabled the detection of polymorphisms between
Coker 797 and NIL carrying 2RL. In order to verify whether the polymorphism detected by primers SJ07 and SJ09 was in fact
the result of the presence of 2RL, additional plant material was examined. Amplified products of about 260 bp fragment with
the SJ07 primer set were generated in rye cvs.“Chilbohomil” and “Jochunhomil”, triticale experimental line Suwon 15, and wheat
experimental line K-14 (1AL/1RS & 2BS/2RL), as well as NIL carrying 2RL and Hamlet, but not in Coker 797 (non-2RL), “Keumgangmil”
(non-translocation wheat), KS92WGRC17 (PI592729 /;/ 6BS/6BL-6RL), KS92WGRC19 (P1592731 /;/ 4BS/4BL-6RL), “TAM200” (1AL/1RS),
and “Siouxland” (1BL/1RS). Our data suggest that primer set SJ07 amplifies a “2RL-specific” fragment of diagnostic value.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
997.
Summary Thirty, one-season-old Rosa canina Inermis seedlings (8–12 mm in diameter) were grown in the greenhouse. After 5 months, single-node softwood cuttings were made of each plant. Analysis of variance demonstrated marked differences between the internode length, number of leaflets per leaf and the leaf area of the original seedling, and between the time of axillary bud-break, axillary sprout length and weight of adventitious roots of their 23-day-old cuttings. Clonal root weight of cuttings was highly significantly correlated with: number of leaflets per leaf (r=–0.65), leaf area (r=+0.65), and days to axillary bud-break (r=+0.62). The origin of heterogeneity among Inermis seedling rootstocks, its probable effect on the flower production of cut roses and its possible use in the selection for clonal rootstocks are discussed. 相似文献
998.
P.N. Sharma Y. Ketipearachchi K. Murata A. Torii S. Takumi N. Mori C. Nakamura 《Euphytica》2003,129(1):109-117
We have constructed a linkage map of the rice brown planthopper (BPH)resistance gene, Bph1. RFLP and AFLP markers were selected by thebulked segregant analysis and used in the mapping study of 262 F2sthat were derived from a cross of `Tsukushibare', a susceptible japonica cultivar, and `Norin-PL3', an authentic japonicaBph1-introgression line. Twenty markers were mapped within a 28.9-cMregion containing the Bph1 locus on the long arm of rice chromosome12. Combining the result of segregation analysis of BPH resistance by themass seedling test and that of the markers, the Bph1 locus wasmapped within a 5.8-cM region between two flanking markers. The closestAFLP markers, em5814N and em2802N, was at 2.7 cM proximal to theBph1 locus. Together with the previously constructed high-resolutionmap of bph2 locating the locus at ca. 10 cM proximal to the Bph1 locus, this improved version of the linkage map would facilitatepyramiding these two important BPH resistance genes. 相似文献
999.
Kevin D. Ming 《Asia Pacific viewpoint》2005,46(1):35-48
Abstract: In recent years, dramatically increasing numbers of mainland Chinese women have entered Hong Kong to engage in sexual labour. Public discourses on the threat of HIV/AIDS increasingly locate these women's bodies as sites of danger, colluding with pre‐existing imaginations of mainland rural women as ignorant, desperate and deceptive in representing these women's penetration of Hong Kong's border as a primary means of infection of the Hong Kong body. Drawing on state, media and popular representations, and the narratives of female sex workers themselves, this paper examines the interwoven bio‐medical, gendered, sexual and cross‐border relationships that intersect in the experiences of mainland Chinese sex workers in Hong Kong. I argue that while images of disease and danger have been used to regulate these women's bodies, mainland female sex workers challenge these images by drawing on other popular stereotypes of mainland women as pure, feminine and traditional. Although images of the related but still ‘other’ figure of the mainland Chinese woman are powerful mechanisms for the regulation of these women's bodies, mainland female sex workers skilfully use inherent tensions in those images in resisting that control and in struggling to achieve their own personal and economic goals. 相似文献
1000.
J. Hill 《Plant Breeding》1993,110(3):212-219
Analysis of a half diallel cross among four white clover cultivars, grown as monocultures and in mixtures (duocultures) with two separate perennial rye-grass cultivars, confirmed that for stolon and leaf number a higher proportion of the genetic variance in duocultures was non-additive. For canopy height and dry weight, however, this proportion was less affected by inter-specific competition. An additive-dominance model of gene action sufficed for all four characters in monocultures, but in duocultures epis-tasis was just one of the factors complicating the genetic picture. This, coupled with short-term reversals in the direction of dominance, merely illustrates the complexity of breeding white clover cultivars. Possible future developments in the breeding of white clover are discussed in the light of these results. 相似文献