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101.
Houcong Wang Huakang Huang Simi Qiu Shi Zhang Yashun Fang Jinlei Cai Xuan Zheng Yumin Huang Ruming Chen Chuanzhi Sun Shuanglong Chen Xiaowen Chi Xinying Liao Weiqing Zhang Xinbin Zhong 《生物学前沿》2007,2(2):144-150
After 20 years of dedicated research,Jiafuzhan has been successfully developed under the new technologies in breeding high-quality early indica rice cultivars.Its rice quality has almost reached the A-level Editable Rice of Agriculture Department of China,and its average production reaches 400-500 kg/(666.7 m2).This new cultivar also has other characteristics such as enhanced resistance of blast and fallen,steady productivity,and strong adaptability.Jiafuzhan has been put into production of over 11.4×104 hm2 in Fujian Province and has been introduced and extended in other Provinces like Jiangxi,Guangdong,and Guangxi,China.The successes of breeding Jiafuzhan is a solution to the existing perennial problems in the rice industry,such as poor grain quality of big-grain rice and early indica rice,low productivity,and poor blast resistance of elite rice. 相似文献
102.
During a long-term study on reproduction of the European rabbit (Oryctolagus cuniculus L.) that was carried out on a population living under semi-natural conditions, occasionally single pups per litter were discovered being stuck in remnants of the foetal membranes. Here we describe this so far unknown phenomenon, quantify the occurrence, and investigate the consequences for the individual growth rate and for survival. Furthermore, we tested if maternal social rank and age were correlated with the occurrence of this phenomenon. Pups comprising the described adherence of the foetal membranes had lower growth rates than their unaffected litter siblings, and usually died during the nestling period or short after emergence above ground. Our findings point out that there was an individual predisposition of the mother for having affected litters. However, an impact of maternal social rank or age on the occurrence of this feature in their offspring was not supported by our data. Nevertheless, a pathological background also has to be considered as a possible cause. 相似文献
103.
Kathryn E. Stanchak Jessica H. Arbour Sharlene E. Santana 《Evolution; international journal of organic evolution》2019,73(8):1591-1603
Neomorphic, membrane‐associated skeletal rods are found in disparate vertebrate lineages, but their evolution is poorly understood. Here we show that one of these elements—the calcar of bats (Chiroptera)—is a skeletal novelty that has anatomically diversified. Comparisons of evolutionary models of calcar length and corresponding disparity‐through‐time analyses indicate that the calcar diversified early in the evolutionary history of Chiroptera, as bats phylogenetically diversified after evolving the capacity for flight. This interspecific variation in calcar length and its relative proportion to tibia and forearm length is of functional relevance to flight‐related behaviors. We also find that the calcar varies in its tissue composition among bats, which might affect its response to mechanical loading. We confirm the presence of a synovial joint at the articulation between the calcar and the calcaneus in some species, which suggests the calcar has a kinematic functional role. Collectively, this functionally relevant variation suggests that adaptive advantages provided by the calcar led to its anatomical diversification. Our results demonstrate that novel skeletal additions can become integrated into vertebrate body plans and subsequently evolve into a variety of forms, potentially impacting clade diversification by expanding the available morphological space into which organisms can evolve. 相似文献
104.
105.
Ting Yi Min Liu Xueyan Li Xueqing Liu Yubin Ding Junlin He Hanting Xu Rufei Gao Xinyi Mu Yanqing Geng Yingxiong Wang Xuemei Chen 《Journal of cellular physiology》2019,234(7):11119-11129
Benzo(a)pyrene (BaP) is an endocrine-disrupting pollutant present in various aspects of daily life, and studies have demonstrated that BaP exerts reproductive toxicity. We previously showed that BaP damages endometrial morphology and decreases the number of implantation sites in early pregnant mice, but the mechanisms underlying these effects remain unclear. The endometrial function is crucial for implantation, which is associated with endometrial cell apoptosis. In this study, we focused on the effect of BaP on endometrial cell apoptosis and the role of WNT signaling during this process. Pregnant mice were gavaged with corn oil (control group) or 0.2 mg·kg−1·day −1 BaP (treatment group) from Days 1 to 6 of pregnancy. BaP impaired endometrial function by decreasing the expression of HOXA10 and BMP2, two markers of receptivity and decidualization. WNT5A and β-catenin were activated in the BaP group. BaP affected the expression of apoptosis-related proteins and inhibited the apoptosis of endometrial stromal cells. In vitro, human endometrial stromal cells (HESCs) were treated with different concentrations of BaP (dimethyl sulfoxide (DMSO); 5, 10 µM). WNT5A and β-catenin were also upregulated in the BaP treatment group. HESC apoptosis was restrained by BaP. Inhibiting WNT5A by SFRP5 partially restored the effect of BaP on apoptosis. In summary, these results suggested that BaP exposure during early pregnancy activates WNT5A/β-catenin signaling pathway, which inhibits the endometrial cell apoptosis and potentially destroys endometrial function. 相似文献
106.
107.
Robert L. Tompkins 《American journal of physical anthropology》1996,99(1):103-118
The relative development of permanent teeth in samples of Neandertal/archaic Homo and Early Modern/Upper Paleolithic hominids is compared to the range of variability found in three recent human samples. Both fossil hominid samples are advanced in relative M2 and M3 development compared to white French-Canadians, but only the Neandertal/archaic Homo M3 sample is advanced when compared to black southern Africans. Both fossil hominid samples are delayed in relative I1 and P3 development compared to the recent human samples. Two hypotheses concerning the significance of the advanced M3 and M2 development found in both hominid groups and southern Africans compared to French-Canadians are discussed. The first postulates that the differences in relative molar development are due simply to variation in tooth/jaw size relationships. The second postulates that the relatively advanced M3 and M2 development found in the fossil hominids and southern Africans is a correlate of their potential for advanced skeletal maturation compared to French-Canadians and other European-derived populations. It appears that dental development patterns have continued to evolve from the Upper Pleistocene to present times, and that Neandertals and Early Moderns shared similar patterns of relative dental development. © 1996 Wiley-Liss, Inc. 相似文献
108.
Se-Il Go Gyung Hyuck Ko Won Sup Lee Jeong-Hee Lee Sang-Ho Jeong Young-Joon Lee Soon Chan Hong Woo Song Ha 《Current issues in molecular biology》2022,44(3):1395
TNM stage still serves as the best prognostic marker in gastric cancer (GC). The next step is to find prognostic biomarkers that detect subgroups with different prognoses in the same TNM stage. In this study, the expression levels of epidermal growth factor receptor (EGFR) and cyclin D1 were assessed in 96 tissue samples, including non-tumorous tissue, adenoma, and carcinoma. Then, the prognostic impact of EGFR and cyclin D1 was retrospectively investigated in 316 patients who underwent R0 resection for GC. EGFR positivity increased as gastric tissue became malignant, and cyclin D1 positivity was increased in all the tumorous tissues. However, there was no survival difference caused by the EGFR positivity, while the cyclin D1-postive group had worse overall survival (OS) than the cyclin D1-negative group in stage I GC (10-year survival rate (10-YSR): 62.8% vs. 86.5%, p = 0.010). In subgroup analyses for the propensity score-matched (PSM) cohort, there were also significant differences in the OS according to the cyclin D1 positivity in stage I GC but not in stage II and III GC. Upon multivariate analysis, cyclin D1 positivity was an independent prognostic factor in stage I GC. In conclusion, cyclin D1 may be a useful biomarker for predicting prognosis in stage I GC. 相似文献
109.
The eggs of many animal species contain a large store of yolk platelets, lipid droplets and glycogen granules; these are consumed during early embryogenesis. However, the mechanisms by which degradation of these stored materials occurs during early embryogenesis are not clearly understood. The mechanisms underlying yolk degradation in amphibian (newt) embryos were investigated. Electron microscopy using an anion marker, cationic ferritin, revealed that yolk platelets were degraded after fusion with late endosomes containing primary lysosomes. Electron microscopy and the results of experiments using a number of reagents with selective effects on intracellular transport suggested that yolk degradation activity in early amphibian embryos may be regulated at the point of fusion between late endosomes and yolk platelets. 相似文献
110.
Organization of the human orphan nuclear receptor Nurr1 gene 总被引:5,自引:0,他引:5