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71.
Claudio J. Bidau Pablo A. Martinez 《Biological journal of the Linnean Society. Linnean Society of London》2016,119(4):816-830
The size variation between males and females of a species is a phenomenon known as sexual size dimorphism (SSD). The observed patterns of variation in SSD among species has led to the formulation of Rensch's rule, which establishes that, in species showing a male size bias, SSD increases with an increase in the body size of the species. However, for species in which there is a female size bias, the SSD would decrease when the body size of the species increases. In the present study, we examined the variation in body size and SSD of 33 species of canids from estimates of body mass and body length. We studied its relationship with life‐history characteristics and tested Rensch's rule using phylogenetic generalized least squares and phylogenetic reduced major axis regressions, respectively. We observed the existence of correlation between body mass and body length, although the SSDs from these estimators are uncorrelated. SSD did not show the pattern predicted by Rensch's rule. SSD also did not show any correlation with life‐history traits. It is likely that the low SSD observed in canids is related to the monogamy observed in the family, which is a rare situation in mammals. 相似文献
72.
H. Zhu L. Gilchrist P. Hayes A. Kleinhofs D. Kudrna Z. Liu L. Prom B. Steffenson T. Toojinda H. Vivar 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(7-8):1221-1232
Fusarium head blight (FHB), an important disease of barley in many areas of the world, causes losses in grain yield and quality. Deoxynivalenol
(DON) mycotoxin residues, produced by the primary pathogen Fusarium graminearum, pose potential health risks. Barley producers may not be able to profitably market FHB-infected barley, even though it has
a low DON level. Three types of FHB resistance have been described in wheat: Type I (penetration), Type II (spread), and Type
III (mycotoxin degradation). We describe putative measures of these three types of resistance in barley. In wheat, the three
resistance mechanisms show quantitative inheritance. Accordingly, to study FHB resistance in barley, we used quantitative
trait locus (QTL) mapping to determine the number, genome location, and effects of QTLs associated with Type-I and -II resistance
and the concentration of DON in the grain. We also mapped QTLs for plant height, heading date, and morphological attributes
of the inflorescence (seeds per inflorescence, inflorescence density, and lateral floret size). QTL analyses were based on
a mapping population of F1-derived doubled-haploid (DH) lines from the cross of the two-rowed genotypes Gobernadora and CMB643, a linkage map constructed
with RFLP marker loci, and field evaluations of the three types of FHB resistance performed in China, Mexico, and two environments
in North Dakota, USA. Resistance QTLs were detected in six of the seven linkage groups. Alternate favorable alleles were found
at the same loci when different inoculation techniques were used to measure Type-I resistance. The largest-effect resistance
QTL (for Type-II resistance) was mapped in the centromeric region of chromosome 2. All but two of the resistance QTLs coincided
with QTLs determining morphological attributes of the inflorescence and/or plant height. Additional experiments are needed
to determine if these coincident QTLs are due to linkage or pleiotropy and to more clearly define the biological basis of
the FHB resistance QTLs. Plant architecture should be considered in FHB resistance breeding efforts, particularly those directed
at resistance QTL introgression and/or pyramiding.
Received: 22 November 1998 / Accepted: 2 June 1999 相似文献
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74.
SUZ12 is a novel putative oncogene promoting tumorigenesis in head and neck squamous cell carcinoma 下载免费PDF全文
Yaping Wu Huijun Hu Wei Zhang Zhongwu Li Pengfei Diao Dongmiao Wang Wei Zhang Yanling Wang Jianrong Yang Jie Cheng 《Journal of cellular and molecular medicine》2018,22(7):3582-3594
The suppressor of zest 12 (SUZ12), one of the core polycomb repressive complex 2 (PRC2) components, has increasingly appreciated as a key mediator during human tumorigenesis. However, its expression pattern and oncogenic roles in head and neck squamous cell carcinoma (HNSCC) remain largely unexplored yet. Here, we sought to determine its expression pattern, clinicopathological significance and biological roles in HNSCC. Through data mining and interrogation from multiple publicly available databases, our bioinformatics analyses revealed that SUZ12 mRNA was significantly overexpressed in multiple HNSCC patient cohorts. Moreover, SUZ12 protein was markedly up‐regulated in primary HNSCC samples from our patient cohort as assessed by immunohistochemical staining and its overexpression significantly associated with cervical node metastasis and reduced overall and disease‐free survival. In the 4‐nitroquinoline 1‐oxide (4NQO)‐induced HNSCC mouse model, increased SUZ12 immunostaining was observed along with disease progression from epithelial hyperplasia to squamous cell carcinoma in tongue. Furthermore, shRNA‐mediated SUZ12 knock‐down significantly inhibited cell proliferation, migration and invasion in HNSCC cells, and resulted in compromised tumour growth in vivo. Collectively, our data reveal that SUZ12 might serve as a putative oncogene by promoting cell proliferation, migration and invasion, and also a novel biomarker with diagnostic and prognostic significance for HNSCC. 相似文献
75.
目的:探讨股骨近端防旋髓内钉、SL-R柄人工股骨头置换术两种术式治疗老年不稳定型骨质疏松性股骨粗隆间骨折的应用效果。方法:选取2015年1月-2017年6月间于河北医科大学附属秦皇岛市第一医院行手术治疗的老年不稳定型骨质疏松性股骨粗隆间骨折患者98例,以数表法将患者随机均分为对照组(n=49)和观察组(n=49)。其中对照组采用股骨近端防旋髓内钉,观察组采用SL-R柄人工股骨头置换术。比较两组患者临床各项指标、手术前后髋关节功能评分以及术后并发症发生情况。结果:观察组手术时间、术中失血量均高于对照组,但住院时间、开始负重时间则低于对照组(P0.05)。观察组术后并发症发生率为4.08%(2/49),低于对照组的18.37%(9/49)(P0.05)。术后1个月、3个月时患者髋关节各项评分相比术前均有升高,术后3个月的各项评分高于术后1个月(P0.05);观察组术后1个月、3个月各项评分均高于对照组(P0.05)。结论:在老年不稳定型骨质疏松性股骨粗隆间骨折患者治疗过程当中,采用SL-R柄人工股骨头置换术可减少住院时间,疗效确切,无严重并发症,且可改善髋关节各项功能评分。 相似文献
76.
77.
Saturation and comparative mapping of a major Fusarium head blight resistance QTL in tetraploid wheat 总被引:2,自引:0,他引:2
Xunfen Chen Justin D. Faris Jinguo Hu Robert W. Stack Tika Adhikari Elias M. Elias Shahryar F. Kianian Xiwen Cai 《Molecular breeding : new strategies in plant improvement》2007,19(2):113-124
Fusarium head blight (FHB) is a devastating disease of cultivated wheat worldwide. Partial resistance to FHB has been identified
in common wheat (Triticum aestivum L.). However, sources of effective FHB resistance have not been found in durum wheat (T. turgidum L. var. durum). A major FHB resistance quantitative trait loci (QTL), Qfhs.ndsu-3AS, was identified on chromosome 3A of T.
dicoccoides, a wild relative of durum wheat. Here, we saturated the genomic region containing the QTL using EST-derived target region
amplified polymorphism (TRAP), sequence tagged site (STS), and simple sequence repeat (SSR) markers. A total of 45 new molecular
marker loci were detected on chromosome 3A and the resulting linkage map consisted of 55 markers spanning a genetic distance
of 277.2 cM. Qfhs.ndsu-3AS was positioned within a chromosomal interval of 11.5 cM and is flanked by the TRAP marker loci, Xfcp401 and Xfcp397.2. The average map distance between the marker loci within this QTL region was reduced from 4.9 cM in the previous study to
3.5 cM in the present study. Comparative mapping indicated that Qfhs.ndsu-3AS is not homoeologous to Qfhs.ndsu-3BS, a major FHB QTL derived from the common wheat cultivar Sumai 3. These results facilitate our efforts toward map-based cloning
of Qfhs.ndsu-3AS and utilization of this QTL in durum wheat breeding via marker-assisted selection. 相似文献
78.
79.
Liane Wehder Günther Ernst Anna C. Crecelius Orlando Guntinas-Lichius Christian Melle Ulrich S. Schubert Ferdinand von Eggeling 《The journal of histochemistry and cytochemistry》2010,58(10):929-937
Carcinoma tissue consists of not only tumor cells but also fibroblasts, endothelial cells or vascular structures, and inflammatory cells forming the supportive tumor stroma. Therefore, the spatial distribution of proteins that promote growth and proliferation in these complex functional units is of high interest. Matrix-assisted laser desorption/ionization imaging mass spectrometry is a newly developed technique that generates spatially resolved profiles of protein signals directly from thin tissue sections. Surface-enhanced laser desorption/ionization mass spectrometry (MS)combined with tissue microdissection allows analysis of defined parts of the tissue with a higher sensitivity and a broader mass range. Nevertheless, both MS-based techniques have a limited spatial resolution. IHC is a technique that allows a resolution down to the subcellular level. However, the detection and measurement of a specific protein expression level is possible only by semiquantitative methods. Moreover, prior knowledge about the identity of the proteins of interest is necessary. In this study, we combined all three techniques to gain highest spatial resolution, sensitivity, and quantitative information. We used frozen tissue from head and neck tumors and chose two exemplary proteins (HNP1–3 and S100A8) to highlight the advantages and disadvantages of each technique. It could be shown that the combination of these three techniques results in congruent but also synergetic data. (J Histochem Cytochem 58:929–937, 2010) 相似文献
80.