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191.
褐飞虱饲养于不同水稻品种、不同生育期以及不同种群密度条件下,5龄若虫翅芽长度与成虫翅型具有稳定的相关性:翅芽长于1.10mm羽化后为长翅型雌虫,介于0.96~1.09mm之间为长翅型雄虫或短翅型雌虫,小于0.95mm为短翅型雄虫。根据5龄若虫翅芽长度结合外生殖器特征,编制了成虫翅型检索表。由此,可在5龄若虫期预测成虫的翅型和种群盛衰的趋势。 相似文献
192.
Zhongqing Chen Weihong Ding Ke Xu Jun Tan Chuanyu Sun Yuancheng Gou Shijun Tong Guowei Xia Zujun Fang Qiang Ding 《PloS one》2012,7(10)
Background
Predicting the recurrence and progression of Non-muscle-invasive bladder cancer(NMIBC) is critical for urologist. Histological grade provides significant prognostic information, especially for prediction of progression. Currently, the 1973 and the 2004 WHO classification co-exist. Which system is better for predicting rumor recurrence and progression still a matter for debate.Methodology/Principal Findings
348 patients diagnosed with Non-muscle invasive bladder cancer were enrolled in our retrospective study. Paraffin sections were assessed by an experienced urological pathologist according to both the 1973 and 2004 WHO classifications. Tumor recurrence and progression was followed-up in all patients. During follow-up, corresponding 5-year recurrence-free survival rates of G1, G2 and G3 were 82.1%, 55.9%, 32.1% and the 5-year progression-free survival rates were 95.9%, 84.4% and 43.3%, respectively. The 5-year recurrence-free survival rates of papillary urothelial neoplasm of low malignant potential (PUNLMP), low-grade papillary urothelial carcinoma(LGPUC) and high-grade papillary urothelial carcinoma (HGPUC) were 69.8%, 67.1% and 42.0% respectively and the 5-year progression-free survival rates were 100%, 90.9% and 54.8% respectively. In multivariate analysis, the 1973 WHO classification significantly associated with both tumor recurrence and progression(p = 0.010 and p = 0.022, respectively); the 2004 WHO classification correlated with tumor progression(p = 0.019), while was not proved to be a variable that can predict the risk of recurrence(p = 0.547). Kaplan-Meier plots showed that both the 1973 WHO and the 2004 WHO classifications were significantly associated with progression-free survival (p<0.0001, log-rank test). For prediction of recurrence, significant differences were observed between the tumor grades classified using the 1973 WHO grading system (p<0.0001, log-rank test), while a significant overlap was observed between PUNLMP and LG plots using the 2004 WHO grading system(p = 0.616, log-rank test).Conclusion/Significance
Both the 1973 WHO and the 2004 WHO Classifications are effective in predicting tumor progression in Non-muscle invasive bladder cancer, while the 1973 WHO Classification is more suitable for predicting tumor recurrence. 相似文献193.
Synthesis and in vitro antitumor activity of 4(3H)-quinazolinone derivatives with dithiocarbamate side chains 总被引:3,自引:0,他引:3
Cao SL Feng YP Jiang YY Liu SY Ding GY Li RT 《Bioorganic & medicinal chemistry letters》2005,15(7):1915-1917
A series of 4(3H)-quinazolinone derivatives with dithiocarbamate side chains were synthesized and tested for their in vitro antitumor activity against human myelogenous leukemia K562 cells. Among them, (3,4-dihydro-2-methyl-4-oxoquinazolin-6-yl)methyl 4-(4-fluorophenyl)piperazine-1-carbodithioate 8q exhibited significant inhibitory activity against K562 cells with IC(50) value of 0.5 microM. 相似文献
194.
195.
196.
Background
The one-step blending approach has been suggested for genomic prediction in dairy cattle. The core of this approach is to incorporate pedigree and phenotypic information of non-genotyped animals. The objective of this study was to investigate the improvement of the accuracy of genomic prediction using the one-step blending method in Chinese Holstein cattle.Findings
Three methods, GBLUP (genomic best linear unbiased prediction), original one-step blending with a genomic relationship matrix, and adjusted one-step blending with an adjusted genomic relationship matrix, were compared with respect to the accuracy of genomic prediction for five milk production traits in Chinese Holstein. For the two one-step blending methods, de-regressed proofs of 17 509 non-genotyped cows, including 424 dams and 17 085 half-sisters of the validation cows, were incorporated in the prediction model. The results showed that, averaged over the five milk production traits, the one-step blending increased the accuracy of genomic prediction by about 0.12 compared to GBLUP. No further improvement in accuracies was obtained from the adjusted one-step blending over the original one-step blending in our situation. Improvements in accuracies obtained with both one-step blending methods were almost completely contributed by the non-genotyped dams.Conclusions
Compared with GBLUP, the one-step blending approach can significantly improve the accuracy of genomic prediction for milk production traits in Chinese Holstein cattle. Thus, the one-step blending is a promising approach for practical genomic selection in Chinese Holstein cattle, where the reference population mainly consists of cows. 相似文献197.
胚胎及生后不同发育时期大鼠睾丸生殖细胞的凋亡 总被引:1,自引:0,他引:1
目的 探索雄性生殖细胞在发育过程中凋亡的特征和规律。方法 利用改进的石蜡切片原位末端标记法(TUNEL法)观察SD大鼠睾丸生殖细胞,对胚胎及生后不同阶段生殖细胞凋亡进行研究。结果 胚胎第13.5天原始生殖细胞即有较高的凋亡率,胚胎第19.5天到出生后第1天,未检测到凋亡生殖细胞,出生后第7天精原细胞分裂增生,伴有较高的凋亡率,与其他各年龄组有显著性差异。出生后第14天精母细胞凋亡率最高,与其他日龄组有显著性差异。结论 SD大鼠雄性生殖细胞发生,发育,成熟过程中都存在凋亡,主要发生在处于细胞增殖过程中的原始生殖细胞,精原细胞和初级精母细胞。 相似文献
198.
<正> 白细胞介素-2(Interleukin-2,IL-2)是一种重要的免疫调节剂,具有促进T细胞增殖和分化,调节NK细胞活性,诱导LAK等功能,在肿瘤治疗上有广泛的应用前景。我们的前文就重组菌中IL-2包含体的制备、性质及重组rIL-2的纯化进行了研究,本文就重组rIL-2纯化过程中影响其活性的有关因素进行了探讨。 相似文献
199.