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91.
92.

Background  

Perturbations in cell-cell interactions are a key feature of cancer. However, little is known about the systematic effects of cell-cell interaction on global gene expression in cancer.  相似文献   
93.

Background  

BMP4 is a member of the transforming growth factor beta (TGFbeta) superfamily and Noggin is a potent BMP inhibitor that exerts its function by binding to BMPs preventing interactions with its receptors. The aim of this work was to investigate the role of BMP4 and Noggin, on oocytes in vitro maturation (m experiments) and embryos in vitro development (c experiments) of bovine.  相似文献   
94.
The present study was conducted primarily to determine the occurrence of polypharmacy in patients with schizophrenia on risperidone. The secondary aim was to ascertain the incidence of inappropriate prescribing with anticholinergics. A retrospective review of the medical records of all patients who were being followed up at the out-patient clinic of a tertiary-care hospital in Malaysia was conducted. Only patients who were being prescribed risperidone between 1 June 2008 and 31 December 2008 were included in the study. Demographic data such as patient’s age, gender and race were obtained from the patient’s medical records. In total, 113 patients met the selection criteria. Polypharmacy was found to occur in 34 patients (30.09%), with the majority (76.47%) being on two antipsychotics. In total, 27 patients (34.18%) on monotherapy with risperidone were prescribed an anticholinergic on scheduled dosing, while 19 patients (24.05%) were prescribed it on an as-needed basis. Of the patients on polypharmacy, 26 (76.47%) were on scheduled dosing of anticholinergics, while three (8.82%) were taking the medication on an as-needed basis. Polypharmacy should be avoided, and the use of anticholinergics should be closely reviewed. By adopting more efficient prescribing practices, costs can be reduced and financial resources can instead be channelled towards more beneficial areas for the patients.  相似文献   
95.
The Faguibine system, northern Mali, consists of a series of interconnected floodplains of which the flooded surface area declined from about 1 000 km² in the late 19th century to only some 90 km² in 2010. Flood extent depends on the height of the Niger River flood peak at Diré. Satellite imagery analysis indicated that a phase shift may have occurred in the year 2000, probably as a delayed consequence of the Sahelian drought of the 1970s compounded by the collapse of societal controls on water use during recent civil conflict. An economic evaluation of the system in 2011 showed US$100 000 per year of net income per flooded km² in Lake Faguibine, allowing vulnerable people to practise recession agriculture, to fish and to graze livestock. An intensive investment phase, combined with an approach of rebuilding local governance systems and environmental management capacity, could yield net benefits to the user communities of the order of ten times the maintenance costs, contributing to human well-being. The system is currently threatened by the building of the Fomi Dam in Guinea and by the planned expansion of irrigation upstream. There is also a risk of the return of a prolonged drought linked to the Atlantic multi-decadal oscillation index.  相似文献   
96.
目的通过高脂饮食建立NAFLD大鼠模型,连续监测4~16周模型动物肝功能、脂质代谢、胰岛素抵抗及肝细胞凋亡在NAFLD进展过程中的变化情况及相互关系,为该模型在脂肪肝发病机制、脂肪肝治疗药物评价等方面的应用提供参考依据。方法 SD大鼠50只,除正常对照组外,其余动物饲喂高脂饲料,分别检测4,8,12,16周大鼠血清GLU、CHO、TG、HDL、LDL、GPT、GOT及胰岛素水平,肝脏组织切片进行病理学及细胞凋亡观察,进一步分析大鼠肝功能、脂质代谢、胰岛素抵抗及肝细胞凋亡对肝组织病理改变的影响。结果模型组大鼠4周后就出现肝功能损伤,脂质代谢紊乱、胰岛素抵抗,肝细胞凋亡8 W后明显增加,肝细胞脂变及炎症为肝组织病理变化的主要特征,且造模时间越长,病变程度越严重。结论经过高脂饲料的喂养,SD大鼠在4~16周内可形成病变程度逐步加重的NAFLD模型,肝功能损伤,脂质代谢紊乱及肝细胞凋亡是引起非酒精性脂肪肝中脂肪变性和炎症的重要因素,该模型可应用于脂肪肝治疗药物评价等方面。  相似文献   
97.
98.
Heat stress in grapevine: the pros and cons of acclimation   总被引:1,自引:0,他引:1       下载免费PDF全文
Heat stress is a major limiting factor of grapevine production and quality. Acclimation and recovery are essential to ensure plant survival, and the recovery mechanisms can be independent of the heat response mechanisms. An experimental set up with and without acclimation to heat followed by recovery [stepwise acclimation and recovery (SAR) and stepwise recovery (SR), respectively] was applied to two grapevine varieties, Touriga Nacional (TN), and Trincadeira (TR), with different tolerance to abiotic stress. Major differences were found between leaves of SAR and SR, especially after recovery; in SAR, almost all parameters returned to basal levels while in SR they remained altered. Acclimation led to a swifter and short‐term antioxidative response, affecting the plant to a lesser extent than SR. Significant differences were found among varieties: upon stress, TN significantly increased ascorbate and glutathione reduction levels, boosting the cell's redox‐buffering capacity, while TR needed to synthesize both metabolites, its response being insufficient to keep the redox state at working levels. TR was affected by stress for a longer period and the up‐regulation pattern of antioxidative stress genes was more obvious. In TN, heat shock proteins were significantly induced, but the canonical heat‐stress gene signature was not evident probably because no shutdown of the housekeeping metabolism was needed.  相似文献   
99.
萨仁 《西北植物学报》2006,26(6):1256-1258
根据对标本的研究及文献资料的整理,证实了西伯利亚岩黄芪在中国的分布;山竹岩黄芪在新疆的分布新记录。另外,还报道了地中海岩黄芪在陕西的栽培记录。  相似文献   
100.
葡萄球菌是动物中重要的机会性病原体,耐甲氧西林金黄色葡萄球菌(MRSA)因其多药耐药的特征日益成为动物和公众健康的主要威胁。由于动物与动物及人畜间存在相互传染的风险,在控制MRSA感染的整个体系中,分析MRSA在动物中的流行显得尤为重要。  相似文献   
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