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1.
ISOPROPYLIDENATIONOFMONOSACCHARIDESCATALYZEDBYSOLIDPHASETiCl_4ISOPROPYLIDENATIONOFMONOSACCHARIDESCATALYZEDBYSOLIDPHASETiCl_4¥...  相似文献   

2.
ANOTEONFIRSTPASSAGETIMESFORGI/M/1TYPEMARKOVPROCESSES¥Xue-Ming;Yuan(InstituteofAutomation,ChineseAcademyofSciences,Beijing,100...  相似文献   

3.
EXPERIMENTSOFSEVERALMETHODSFORGEO-POINT-PROCESSPREDICTIONEXPERIMENTSOFSEVERALMETHODSFORGEO-POINT-PROCESSPREDICTION¥WangJin-fe...  相似文献   

4.
张曙云 《科技通报》1996,12(1):61-64
应用Southern印迹杂交法、高压琼脂糖凝胶电泳和标准的微量淋巴细胞毒试验对中国汉族人44例正常无相关个体进行了C4基因限制性片段长度多态性(RFLP)、C4蛋白分型及HLA-DR分型的测定,结果发现C4RFLP A、B二种格局在C4B*Q0的表现型上有显著差异(P〈0.05);RFLP A型格局与DR4相关(P〈0.05)。  相似文献   

5.
DETERMINATIONOFCYCLOTRIME-THYLENETRINITRAMINEINSERUMOFRABBITBYRP-HPLCChenYong;YuanZhuo-bin(GraduateSchool,AcademiaSinica.Beij...  相似文献   

6.
MARC格式与传统手工编目格式相比有许多差异,文章分析了两者的区别并论述了MARC格式的优越性。  相似文献   

7.
SYNTHESISANDPROPERTIESOFHEPARINIZEDPOLYMETHACRYLICACID¥FengPinzhen;LuJiantao(DepartmentofChemistry,GraduateSchool,AcademiaSin...  相似文献   

8.
DEVELOPMENTOFAVACUUMSPARKDISCHARGESOURCEDEVELOPMENTOFAVACUUMSPARKDISCHARGESOURCE¥GuoYu-bin;LiFu-tian(ChangchunInatitideofOpti...  相似文献   

9.
SINGLE-SWEEPOSCILLOPOLARO-GRAPHICANALYSISOFP-NITROBENZOICACID¥YuanZhuo-bin;HanFeng-mei;ChenYong;WuYan-xia(GraduateSchool,Chin...  相似文献   

10.
ARCH预警系统的研究   总被引:11,自引:1,他引:10  
王慧敏 《预测》1998,17(4):55-56
ARCH模型可以用过去误差解释未来预测误差。本文将ARCH模型引入宏观经济预警,讨论了ARCH预警系统的指标设计、ARCH预警方法以及预警警限的界定,给出了一种具有ARCH特征的警限界定方法  相似文献   

11.
氟他胺加睾丸切除治疗晚期前列腺癌22例报告   总被引:2,自引:0,他引:2  
王慎鸿 《科技通报》2001,17(3):71-73
为探讨提高晚期前列腺癌的治疗效果,回顾性研究22例晚期前列腺癌的临床资料,运用氟他胺加睾丸切除治疗前列腺癌,其中C2期8例,D1期9例,D2期5例。结果:显效17例,有效3例,死亡2例,总有效率达90.9%。结果表明氟他胺是一个单纯抗雄激素的非类固醇化合物,对前列腺组织靶细胞膜上的雄激素受体有特异性阻断作用,能抑制雄激素依赖性肿瘤细胞生长,切除睾丸能降低雄激素水平,两者产生协同作用,提高疗效。  相似文献   

12.
The objective of study was to evaluate and correlate the pathological characteristics of breast cancer patients with estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2/neu) detected by immunohistochemistry and/or fluorescent in situ hybridization method. We have conducted 2 year study of 204 cases of breast cancer at HCG-Medisurge Hospitals, Ahmedabad from 2009 to 2011. Significant correlation was found in ER and PR expression whereas no correlation was found in hormonal receptors and Her2/neu expression. ER and PR positivity increased with advancing age in breast carcinoma patients while not affecting Her2/neu expression. The expression of hormone receptors were higher in infiltrating lobular carcinoma and infiltrating duct carcinoma subtypes of breast carcinoma as compared to other subtypes such medullary and in situ carcinoma. High-grade carcinoma patients were predominantly ER/PR negative and Her2/neu positive as compared to lower grade breast carcinoma whereas high-stage carcinoma patients were ER/PR positive and Her2/neu positive as compared to lower stage breast carcinoma.  相似文献   

13.
In this paper, we study the variation of the thickness of patterned microchannel features in photoresist (PR) by two-step photolithography. The final PR thickness is determined by the thickness and width of the predefined PR pattern in the first-step lithography and the thickness of the spin-coated PR film in the second-step lithography. Thickness variation is demonstrated to be an important consideration within the critical pattern width that the capillary pressure is still dominant for forming the PR film thickness. With this mechanism of two-step photolithography, we demonstrate its ability to form multilevel channel features and its use to fabricate a cross-flow filter with two different pore sizes as a microfluidic application.  相似文献   

14.
The present study aimed to investigate the effect of 3,3′-diindolylmethane (DIM) on inflammatory markers, estrogen receptors (ER), progesterone receptors (PR), level of glycoprotein and the mast cell population in 7,12-dimethylbenz (a) anthracene (DMBA) 25 mg/kg b.wt. induced rat mammary carcinogenesis. After 8 weeks of tumor formation, rats had access to an oral administrated with DIM 10 mg/kg b.wt. and DIM@CS-NP 0.5 mg/kg body weight respectively for 8 weeks. The oral administration of DIM@CS-NP 0.5 mg/kg b.wt. suppressed the Cox-2, NF-κB and TNF-α protein expression on DMBA induced rats compared to DIM 10 mg/kg b.wt. The ER/PR levels were increased on DMBA induced rats, treated with DIM@CS-NP 0.5 mg/kg b.wt. reduced ER/PR level as well as glycoprotein and mast cell population than DIM 10 mg/kg b.wt. The result shows that, DIM@CS-NP 0.5 mg/kg b.wt. has the potentially inhibit abnormal levels of inflammatory markers, ER, PR, levels of glycoprotein and mast cell population compared to DIM 10 mg/kg b.wt.  相似文献   

15.
A decrease in the membrane anchored erythrocyte complement receptor 1 (CR1) is reported as an acquired phenomenon in a number of inflammatory and autoimmune diseases with concomitant rise in soluble CR1 (sCR1) levels in plasma. There is a need to establish the normal range of sCR1 in Indian adults to assess the function and disease association of this protein. The plasma sCR1 levels of 50 healthy individuals have been estimated by an indigenously developed sandwich ELISA. sCR1 levels from 26 patients suffering from nephropathies had also been assayed which was much higher than the normal controls. This observation suggests sCR1 as a potential market for the assessment of disease activity in nephropathies.  相似文献   

16.
L-carnitine is popular as a potential ergogenic aid because of its role in the conversion of fat into energy. The present study was undertaken to investigate the effect of short term supplementation of L-carnitine on metabolic markers and physical efficiency tests under short term calorie restriction. Male albino rats were divided into four groups (n = 12 in each)—control, calorie restricted (CR for 5 days, 25 % of basal food intake), L-carnitine supplemented (CAR, given orally for 5 days at a dose of 100 mg/kg), CR with L-carnitine supplementation (CR + CAR). Food intake and body weight of the rats were measured along with biochemical variables like blood glucose, tissue glycogen, plasma and muscle protein and enzymatic activities of CPT-1 (carnitine palmitoyl transferase-1) and AMP kinase. Results demonstrated that L-carnitine caused marked increase in muscle glycogen, plasma protein, CPT-1 activity and swim time of rats (P < 0.05) on short term supplementation. In addition to the substantive effects caused by CR alone, L-carnitine under CR significantly affected muscle glycogen, plasma protein, CPT-1 activity and AMP kinase (P < 0.05). Short term CR along with L-carnitine also resulted in increased swim time of rats than control, CR and L-carnitine treated rats (P < 0.05). The present study was an attempt towards developing an approach for better adherence to dietary restriction regimen, with the use of L-carnitine.  相似文献   

17.
曾英姿 《情报科学》2006,24(10):1494-1500
本文对SSCI、AHCI1997—2004共八年间收录的中国著者论文数量及其变化趋势、论文合作国家或地区分布、期刊分布、机构分布、语言分布、主题分布等情况进行了统计分析。发现我国大陆被SSCI、A&HCI收录的期刊与论文仍然甚少,语言及机构分布规律仍然未发生变化,但论文主题与国际合作态势却能够在一定程度上反映该时期我国社科研究的热点。  相似文献   

18.
The misfolding of amyloid-β (Aβ) peptides from the natural unfolded state to β-sheet structure is a critical step, leading to abnormal fibrillation and formation of endogenous Aβ plaques in Alzheimer''s disease (AD). Previous studies have reported inhibition of Aβ fibrillation or disassembly of exogenous Aβ fibrils in vitro. However, soluble Aβ oligomers have been reported with increased cytotoxicity; this might partly explain why current clinical trials targeting disassembly of Aβ fibrils by anti-Aβ antibodies have failed so far. Here we show that Au23(CR)14 (a new Au nanocluster modified by Cys-Arg (CR) dipeptide) is able to completely dissolve exogenous mature Aβ fibrils into monomers and restore the natural unfolded state of Aβ peptides from misfolded β-sheets. Furthermore, the cytotoxicity of Aβ40 fibrils when dissolved by Au23(CR)14 is fully abolished. More importantly, Au23(CR)14 is able to completely dissolve endogenous Aβ plaques in brain slices from transgenic AD model mice. In addition, Au23(CR)14 has good biocompatibility and infiltration ability across the blood–brain barrier. Taken together, this work presents a promising therapeutics candidate for AD treatment, and manifests the potential of nanotechnological approaches in the development of nanomedicines.  相似文献   

19.
中国粮食价格波动的农户福利效应研究   总被引:2,自引:1,他引:1  
苗珊珊 《资源科学》2014,36(2):370-378
本文基于1978-2011年中国粮食生产与消费的相关数据,在对粮食供需弹性以及粮食收益率估计的基础上,运用Minot福利效应模型,对粮食价格波动中农户福利的变动进行了测算与分解。结果表明:粮食价格波动的农户福利效应由两方面组成,包括农户作为净生产者的福利变动和其作为净消费者的福利变动。生产福利变动与粮食生产价格变动具有同向作用关系,粮食生产价格平均每提高10%,农户的短期生产福利将增加2.17%,长期生产福利增加2.19%;而消费福利变动与粮食销售价格变动具有负向作用关系,粮食销售价格平均每提高10%,短期消费福利减少1.44%,长期消费福利将减少1.34%。粮食价格变动引起农户收入与粮食消费支出变化的相对值决定农户总福利效应。最后本文分析了这一结论的政策性含义。  相似文献   

20.
Previous studies on Course Recommendation (CR) mainly focus on investigating the sequential relationships among courses (RNN is applied) and fail to learn the similarity relationships among learners. Moreover, existing RNN-based methods can only model courses’ short-term sequential patterns due to the inherent shortcomings of RNNs. In light of the above issues, we develop a hyperedge-based graph neural network, namely HGNN, for CR. Specifically, (1) to model the relationships among learners, we treat learners (i.e., hyperedges) as the sets of courses in a hypergraph, and convert the task of learning learners’ representations to induce the embeddings for hyperedges, where a hyperedge-based graph attention network is further proposed. (2) To simultaneously consider courses’ long-term and short-term sequential relationships, we first construct a course sequential graph across learners, and learn courses’ representations via a modified graph attention network. Then, we feed the learned representations into a GRU-based sequence encoder to infer their short-term patterns, and deem the last hidden state as the learned sequence-level learner embedding. After that, we obtain the learners’ final representations by a product pooling operation to retain features from different latent spaces, and optimize a cross-entropy loss to make recommendations. To evaluate our proposed solution HGNN, we conduct extensive experiments on two real-world datasets, XuetangX and MovieLens. We conduct experiments on MovieLens to prove the extensibility of our solution on other collections. From the experimental results, we can find that HGNN evidently outperforms other recent CR methods on both datasets, achieving 11.96% on P@20, 16.01% on NDCG@20, and 27.62% on MRR@20 on XuetangX, demonstrating the effectiveness of studying CR in a hypergraph, and the importance of considering both long-term and short-term sequential patterns of courses.  相似文献   

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