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61.
以小麦的芽长和根长为测试指标,测定了安全剂二氯丙烯胺和苯叉酰胺对乙草胺的解毒作用.试验结果表明:两种安全剂对乙草胺均有明显解毒作用,其中以乙草胺5.0 μg/mL混施二氯丙烯胺10.0 μg/mL后的解毒效果最好,对小麦芽解毒作用达到18.75%;乙草胺0.5 μg/mL混施苯叉酰胺20.0 μg/mL后的解毒效果最好,对小麦芽解毒作用达到13.07%.但两种安全剂不能完全解除乙草胺对小麦幼芽与幼根的毒害作用.  相似文献   
62.
津绿67号是抗病、耐热、丰产的黄瓜一代杂种,其母本、父本分别为自交系R08116144和L09282221。该品种植株生长势强,中早熟,第一雌花节位4~5节,瓜码密,雌花节率40%以上;耐热,抗霜霉病、枯萎病和CMV等病害;商品瓜棒状,顺直,把短粗,刺密、瘤中等大小;瓜色深绿、光泽度好。腰瓜长约32cm,单瓜质量在220g左右;露地栽培产量可达5000kg/667m^2,适合春、秋露地栽培;于2018年进行品种权申请并已受理,农业部于11月1日进行了品种权申请公告(总第116期),申请号:28182196.6。  相似文献   
63.
5-Reductase inhibitory activity of methanol extracts of the heartwood of 13 tropical wood species were examined. Strong 5-reductase inhibitory activity was observed withShorea species. From melapi (Shorea sp.), two known resveratrol trimers, vaticanol A and ampelopsin C, and two novel trimers were isolated as active compounds. The structures of the two novel resveratrol trimers were elucidated by one- and two-dimensional nuclear magnetic resonance spectroscopic analyses, including1H-1HCOSY, HMQC, and HMBC. The compounds were named melapinol A and melapinol B. There were no significant differences among the 5-reductase inhibitory activities of the four resveratrol trimers, which were significantly stronger than those of-linolenic acid and epigallocatechin gallate, known 5-reductase inhibitors.  相似文献   
64.
The aims of this study were to establish expression of epidermal growth factor receptor (EGFR) and Ki67 in 67 archived biopsy samples of feline oral squamous cell carcinomas (FOSCCs) and to establish if the expression of either markers was predictive of survival. Samples were immunohistochemically labelled for the two proteins and scored. Statistical analyses of data, including Kaplan-Meier survival curves, were performed. All samples expressed both markers although levels differed between samples. Median overall survival was 46 days and 1-year survival was 5%. There was no correlation between Ki67 and EGFR scores (Pearson's correlation coefficient, P = 0.861). Low cellular proliferation (low Ki67 score) was positively correlated with an overall longer survival (Log Rank, P = 0.02) and a trend towards better survival for the high EGFR group was observed (Log Rank, P = 0.076). Ki67 and EGFR immunostaining in FOSCC may be of value as biochemical markers for screening of biopsies from cases of FOSCC.  相似文献   
65.
Indolent lymphoma comprises up to 29% of all canine lymphoma; however, limited information exists regarding the subtypes and biological behaviour. This retrospective study describes the clinical characteristics, histopathological and immunohistochemical features, treatment, outcome and prognostic factors for 75 dogs with indolent lymphoma. WHO histopathological classification and immunohistochemistry (IHC) for CD79a, CD3, Ki67 and P‐glycoprotein (P‐gp) was performed. The most common histopathological subtype was T‐zone, 61.7%, (MST 33.5 months), followed by marginal zone, 25%, (MST 21.2 months), P = 0.542. The addition of IHC to preliminary histopathological classification resulted in a revised diagnosis in 20.4% of cases. The use of systemic treatment did not influence survival, P = 0.065. Dogs treated with chlorambucil and prednisone did not reach a MST, compared with a MST of 21.6 months with CHOP‐based chemotherapy, P = 0.057. The overall MST of 4.4 years confirms that this is indeed an indolent disease. However, the effect of systemic treatment must be determined through prospective trials.  相似文献   
66.
The growth fraction of 68 canine cutaneous melanomas was determined by immunostaining with MIB‐1, a monoclonal antibody to a Ki‐67 epitope that recognizes all proliferating cells. Fifty tumours were classified histologically as benign and 18 as malignant. The Ki‐67 proliferative index (percentage of positive cells over 500 neoplastic cells) was low (< 15%) in 55 cases and high ( 15%) in 13 cases. High Ki‐67 proliferative index and histological malignancy were both associated with significantly poorer 2‐year survival (P < 0.0001). However, the predictive value of the Ki‐67 proliferative index (97%) was higher than the predictive value of classical histology (91%). The evaluation of the growth fraction by the Ki‐67 proliferative index is highly predictive of the biological behaviour of canine cutaneous melanoma.  相似文献   
67.
A cortisol‐secreting adrenocortical tumour (ACT) is the cause of naturally occurring canine hypercortisolism in approximately 15% to 20% of cases. The differentiation between an adrenocortical adenoma and carcinoma is usually based on histopathology. However, histopathological parameters have never been linked to the dogs' survival. Moreover, in human medicine the inter‐observer variability of some histopathological parameters that are used for ACTs is high. The objective of this study was to establish a reliable and easy‐to‐use histopathological scoring system for cortisol‐secreting ACTs that can assess the prognosis of dogs after adrenalectomy. Cortisol‐secreting ACTs of 50 dogs, collected between 2002 and 2015, were included in this study. Twenty histopathological features were assessed by one veterinary pathologist and one resident in veterinary pathology. In addition, the Ki67 proliferation index was assessed by two observers. Only parameters with intra‐ and inter‐observer agreement scores (intra‐class correlation or Cohen's kappa coefficient) of ≥0.40 were included in survival analyses. Use of multivariate forward stepwise regression analysis with associated hazard ratios led us to a scoring system which we call the Utrecht score: the Ki67 proliferation index, +4 if more than 33% of the tumour cells have clear/vacuolated cytoplasm and + 3 if necrosis is present. Using cut‐off values of 6 and 11, we could distinguish three groups that had significantly shorter survival times with increasing Utrecht scores. We conclude that the Utrecht score can be used to assess the prognosis of dogs with cortisol‐secreting ACTs after adrenalectomy, which can help to select high‐risk dogs that might benefit from adjuvant treatment or additional monitoring.  相似文献   
68.
采用对峙培养法和含毒介质法测定67-1菌株和无菌发酵液对水稻纹枯病菌的抑制作用和对菌核形成的影响;测定67-1菌株孢子悬浮液和无菌发酵液处理不同时间对菌核萌发的抑制作用;采用种子处理和土壤处理的方法测定67-1菌株孢子悬浮液对水稻幼苗生长的影响;通过室内盆栽试验和田间药效试验,测定67-1菌株孢子粉对水稻纹枯病的防病效果。结果表明,67-1菌株及其无菌发酵液对水稻纹枯病菌的菌丝生长、菌核的形成有明显的抑制作用,发酵液60℃处理30min后抑菌率有所下降,121℃处理30min抑菌活性丧失;孢子悬浮液和无菌发酵液处理不同时间菌核萌发率明显下降;67-1菌株孢子悬浮液土壤和种子处理后,能够提高水稻发芽率,促进水稻的生长;750g/hm2的孢子粉对水稻纹枯病有较好的防治作用,田间试验防病效果和保产效果分别达69.1%和22.4%,与20%井冈霉素可湿性粉剂没有显著差异。  相似文献   
69.
脑胶质瘤是颅内常见恶性肿瘤,常规的治疗手段很难将其完全治愈.67 kD层连蛋白受体(67 kDlaminin receptor,67LR)属于高亲和,非整联蛋白家族成员,试验表明,该蛋白在许多癌细胞表面过量表达,并且其表达水平与肿瘤细胞的粘附、增殖、分化、迁移、信号转导及转移能力密切相关.本试验利用shRNA干扰、RT-PCR、免疫细胞化学和MTT等技术通过下调67LR基因的表达来探讨其在胶质瘤细胞中的表达情况,及其对胶质瘤细胞增殖能力的影响.结果发现,相对于正常脑组织,67LR在脑胶质瘤细胞表面大量表达.采用shRNA下调其表达后发现胶质瘤细胞的增殖能力明显降低.结果表明,67LR在胶质瘤细胞表面的过表达与此细胞的增殖能力呈明显相关.  相似文献   
70.
种子发育过程是植物整个生长周期最重要的阶段,涉及到一系列功能物质的合成和转化,是由各种相互关联的基因共同控制完成的,因此,研究该阶段特异性表达的基因对研究种子发育过程非常重要。以种子特异性表达的基因At LCR67为研究对象,通过构建RNAi干扰质粒,借助根癌农杆菌介导的浸花法,将At LCR67基因的RNAi表达框转到拟南芥基因组中;经过PPT抗性筛选与PCR鉴定,成功获得了8株转基因植株。对其中的3株进一步作RT-PCR检测,显示有2株中的At LCR67基因表达被完全抑制,另一株的基因表达水平被抑制了大约70%,结果完全实现了设计目标;同时还发现T2代植株有晚花表型。这两株转基因植株为进一步研究At LCR67功能与作用机制提供了良好的遗传材料。  相似文献   
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