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91.
The localization of soluble endoplasmic reticulum (ER) chaperones in the cell organelle is mediated by the C‐terminal KDEL (lysine, aspartic acid, glutamic acid and leucine) motif. This motif is recognized by the KDEL receptor, a seven‐transmembrane protein that cycles between the ER and cis‐Golgi to capture missorted KDEL chaperones from post‐ER compartments in a pH‐dependent manner. The KDEL receptor's target chaperones have a substantial role in protein folding and assembly. In this study, the gene expression level of KDEL receptor 1 shows a moderate upregulation during either ER stress or growth of Chinese hamster ovary (CHO) cells in batch culture, while the ER chaperones show higher upregulation. This might indicate the possibility of saturation of the ER retention machinery or at least hindered retention during late stage batch culture in recombinant CHO cells. KDELR1 is overexpressed in a monoclonal antibody‐producing CHO cell line to improve the intracellular chaperone retention rate in the ER. An increase in the specific productivity of IgG1 by 13.2% during the exponential phase, and 23.8% in the deceleration phase of batch culture is observed. This is the first study to focus on the ER retention system as a cell engineering target for enhancing recombinant protein production.  相似文献   
92.
研究土壤微生物生物量及其生态化学计量特征对造林树种转换的响应,对深入了解森林生态系统土壤养分循环和有效性具有重要意义。本研究以1993年春在二代杉木采伐迹地上营造的26年生米老排和杉木人工林为对象,采用氯仿熏蒸法测定了0~40 cm土层土壤微生物生物量碳(MBC)、氮(MBN)、磷(MBP)的变化。结果表明: 与杉木人工林相比,米老排人工林0~10 cm土层MBC和0~20 cm土层MBN和MBP均显著提高, 0~20 cm土层MBC/MBP和10~20 cm土层MBN/MBP显著降低。两种人工林所有土层MBC/MBN均无差异。相关分析显示,土壤含水率、总有机碳、总氮、全磷、有效磷与MBC、MBN和MBP呈显著正相关,而与MBC/MBP和MBN/MBP呈显著负相关。逐步线性回归分析表明,MBN和MBP主要受土壤总氮和有效磷的影响,而MBC/MBP和MBN/MBP主要受有机碳和有效磷的驱动。研究表明,造林树种从杉木转换成米老排能够增加表层土壤微生物生物量,加速氮磷养分周转,增加土壤氮磷养分供应能力。米老排人工林土壤MBP的增加可能在一定程度上缓解了树木生长的磷限制。  相似文献   
93.
肝脏是人体腹腔内最大的实体器官,对维持机体的基本生理功能起着至关重要的作用。肝脏疾病是威胁人类健康的常见病多发病。全球约有10%人口受到不同程度的肝脏疾病的危害,其中,肝纤维化往往成为这些疾病的晚期病理特征。由于肝纤维化的发病机制复杂,尚无有效的合成类药物能够治疗肝纤维化。中药治疗肝纤维化具有多靶点和副作用小的优势。本文综述了肝纤维化的病理特征与诱发炎症的关系,讨论了中药治疗肝纤维化的单味中药、传统配方及其化学活性成分的抗炎症机制。  相似文献   
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Aidi injection (ADI), a traditional Chinese biomedical preparation, is a promising adjuvant therapy for gynecologic tumors (GTs), including cervical cancer (CC), endometrial cancer (EC), and ovarian cancer (OC). Although studies have reported positively on ADI therapy, its exact effects and safety in GT patients remain controversial. Therefore, a wide-ranging systematic search of electronic databases was performed for this meta-analysis. Data from 38 trials including 3309 GT patients were analyzed. The results indicated that the combination of conventional treatment and ADI markedly improved the patients’ overall response rate (P<0.00001), disease control rate (P<0.00001), and quality of life (P<0.05) compared with conventional treatment alone. Furthermore, patient immunity was enhanced with combined treatment, as indicated by significantly increased percentages of CD3+ (P=0.005) and CD4+ (P<0.00001) and increased CD4+/CD8+ ratio (P=0.001). Most of the adverse events caused by radiochemotherapy such as gastrointestinal issues, leukopenia, thrombocytopenia, and hepatotoxicity, (P<0.05 for all) were significantly alleviated when ADI was used in the GT patients. However, other adverse events such as nephrotoxicity, diarrhea, alopecia, and neurotoxicity did not significantly differ between the two groups. Overall, these results suggest that the combination of conventional and ADI treatment is more effective than conventional treatment alone.  相似文献   
96.
Background and AimsRoot sprouting (RS), i.e. the ability to form adventitious buds on roots, is an important form of clonal growth in a number of species, and serves as both a survival strategy and a means of spatial expansion, particularly in plants growing in severely and recurrently disturbed habitats. Occurrence and/or success of plants in severely and recurrently disturbed habitats are determined by two components, namely the ability to produce adventitious buds on roots and the vigour of their production. As mechanisms behind different magnitudes of RS remain unclear, our study investigates: (1) whether the presence or absence of specific tissues in roots can promote or limit RS; and (2) whether there is some relationship between RS ability, RS vigour and species niche.MethodsWe studied RS ability together with RS vigour in 182 Central European herbaceous species under controlled experimental conditions. We used phylogenetic logistic regressions to model the presence of RS, RS vigour, the relationship between RS and anatomical traits and the relationship between RS and parameters of species niches.Key ResultsA quarter of herbs examined were able to produce adventitious buds on roots. They were characterized by their preference for open dry habitats, the presence of secondary root thickening and the occurrence of sclerified cortical cells in roots. Root sprouting vigour was not associated with any specific anatomical pattern, but was correlated with the environmental niches of different species, indicating that preferred disturbed and dry habitats might represent a selection pressure for more vigorous root sprouters than undisturbed and wet habitats.ConclusionsOur study shows that sprouting from roots is quite common in temperate dicotyledonous herbs. Two components of RS – ability and vigour – should be considered separately in future studies. We would also like to focus more attention on RS in herbs from other regions as well as on external forces and internal mechanisms regulating evolution and the functions of RS in both disturbed and undisturbed habitats.  相似文献   
97.
In recent years, Chinese goral (Nemorhaedus griseus) carcasses were frequently found in the mid-Qinling Mountains. In order to assess the spatial distribution pattern of goral carcasses, data of the individuals from Shaanxi's Fourth Giant Panda Survey was used in this study to analyse how the gorals/goral carcasses sites were related to altitude, slope, aspect, river, and road through quantitative analyses. The results showed:(1) the correlation between the sites of goral carcasses and topographic factors was relatively significant. Goral carcasses tend to be found at relatively low altitude (1 200-2 400 m) and mild slope (6°-25°). The chi-square test also showed that the aspect of the goral carcasses sites was significantly different from the goral sites. Most of the goral carcasses were found at south-facing/half southfacing slopes. (2) The correlation between the sites of goral carcasses and the distance to river was significant. The kernel density analysis and Z-test further showed that there were significant differences between the gorals/goral carcasses sites and the distance to river. Most of the goral carcasses sites were close to river (< 100 m). (3) The correlation between the sites of goral carcasses and the distance to road was not significant. Kernel density analysis and Z-test showed that there was no significant difference between the sites of gorals/goral carcasses and the distance to road. This study proposed several suggestions about how to strengthen the protection of gorals in the future.  相似文献   
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99.
通过控制大鲵仿生态繁育池进水量模拟旅游干扰下的水质溶解氧特征,采用红外数字监控系统研究大鲵繁殖行为(产卵与护卵)及繁殖力(相对产卵量、受精率与孵化率)特点,分析它们与水质的关系,探讨旅游干扰导致的水质变化对大鲵繁殖行为及繁殖力的影响。结果表明: 与对照组相比,旅游干扰下大鲵的产卵行为与繁殖力未受到显著影响,但雄鲵护卵行为中的扇尾与搅动时间显著延长,以提高水中溶解氧浓度,满足大鲵胚胎发育需求;此外,旅游干扰下受精卵的孵化时间显著延长,但孵化率未受到显著影响。雄鲵护卵行为变化与受精卵孵化时间延长可能是大鲵对旅游干扰导致的水质变化的一种主动响应。  相似文献   
100.
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