全文获取类型
收费全文 | 104篇 |
免费 | 0篇 |
专业分类
教育与普及 | 1篇 |
现状及发展 | 39篇 |
研究方法 | 10篇 |
综合类 | 52篇 |
自然研究 | 2篇 |
出版年
2019年 | 1篇 |
2018年 | 1篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2008年 | 2篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 6篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1986年 | 1篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1972年 | 5篇 |
1969年 | 2篇 |
1968年 | 3篇 |
排序方式: 共有104条查询结果,搜索用时 15 毫秒
51.
探讨了北九州市新规划热供给区域的热电并给系统导入效果.根据东京的能源消费功能单位,推测了北九州市的能源消费功能单位.利用不同建筑用途的建筑面积和能源消费功能单位,计算了北九州市新规划热供给区域的能源需要量、设定了单体空调系统、锅炉系统、电主热从及热主电从的热电并给系统等4种能源供给系统,并计算了各系统的能源消费量、二氧化碳排放量、初期投资、运行费用和单纯回收年数、计算结果表明,综合考虑能源消费量、二氧化碳排放量和运行费用,新规划热供给区域导入能源供给系统时,热电并给系统是最好的选择. 相似文献
52.
53.
Heterozygous TGFBR2 mutations in Marfan syndrome 总被引:24,自引:0,他引:24
Mizuguchi T Collod-Beroud G Akiyama T Abifadel M Harada N Morisaki T Allard D Varret M Claustres M Morisaki H Ihara M Kinoshita A Yoshiura K Junien C Kajii T Jondeau G Ohta T Kishino T Furukawa Y Nakamura Y Niikawa N Boileau C Matsumoto N 《Nature genetics》2004,36(8):855-860
Marfan syndrome is an extracellular matrix disorder with cardinal manifestations in the eye, skeleton and cardiovascular systems associated with defects in the gene encoding fibrillin (FBN1) at 15q21.1 (ref. 1). A second type of the disorder (Marfan syndrome type 2; OMIM 154705) is associated with a second locus, MFS2, at 3p25-p24.2 in a large French family (family MS1). Identification of a 3p24.1 chromosomal breakpoint disrupting the gene encoding TGF-beta receptor 2 (TGFBR2) in a Japanese individual with Marfan syndrome led us to consider TGFBR2 as the gene underlying association with Marfan syndrome at the MSF2 locus. The mutation 1524G-->A in TGFBR2 (causing the synonymous amino acid substitution Q508Q) resulted in abnormal splicing and segregated with MFS2 in family MS1. We identified three other missense mutations in four unrelated probands, which led to loss of function of TGF-beta signaling activity on extracellular matrix formation. These results show that heterozygous mutations in TGFBR2, a putative tumor-suppressor gene implicated in several malignancies, are also associated with inherited connective-tissue disorders. 相似文献
54.
Germline KRAS and BRAF mutations in cardio-facio-cutaneous syndrome 总被引:15,自引:0,他引:15
Niihori T Aoki Y Narumi Y Neri G Cavé H Verloes A Okamoto N Hennekam RC Gillessen-Kaesbach G Wieczorek D Kavamura MI Kurosawa K Ohashi H Wilson L Heron D Bonneau D Corona G Kaname T Naritomi K Baumann C Matsumoto N Kato K Kure S Matsubara Y 《Nature genetics》2006,38(3):294-296
Cardio-facio-cutaneous (CFC) syndrome is characterized by a distinctive facial appearance, heart defects and mental retardation. It phenotypically overlaps with Noonan and Costello syndrome, which are caused by mutations in PTPN11 and HRAS, respectively. In 43 individuals with CFC, we identified two heterozygous KRAS mutations in three individuals and eight BRAF mutations in 16 individuals, suggesting that dysregulation of the RAS-RAF-ERK pathway is a common molecular basis for the three related disorders. 相似文献
55.
内蒙古岱海古盐度定量复原初探 总被引:18,自引:1,他引:17
通过分析湖泊表层沉积物中活体介形类(Limnocythere cf。inopinata)壳体的Sr,Ca比值以及湖水的Sr^2+,Ca^2+比值,获取岱海介形类壳体的Sr分配系数Kd(Sr)。利用湖水Sr^2+/Ca^2+值与盐度的相关关系,建立岱海湖水盐度与水介质离子比函数方程。结合岱海沉积钻孔中同种介形类壳体的 Sr,Ca比值,定量恢复湖水的古盐度。 相似文献
56.
57.
K. Matsumoto M. Shimojo M. Nogawa M. Okudomi 《复旦学报(自然科学版)》2005,44(5):768-769
Enzymatic kinetic resolution of racemic alcohols or esters is known as a useful method for the preparation of optically active secondary alcohols. However, the work-up including the separation of the mixture of the remaining substrate and the resulting compound spend a lot of time and waste much amount of solvents. On the other hand, organic synthesis based on polymer supports has made rapid progress. Although the methodology is potentially useful for the easy separation of compounds obtained by the enzymatic reaction, there have been relatively few reports on enzymatic resolutions of using a polymer so far. We have noticed that using a watersoluble polymer could be suitable for enzymatic transformation. Here, we report the first example of an enzyme-mediated enantioseleetive hydrolysis of poly(ethylene glycol)(PEG)-supported substrates with a carbonate moiety to afford optically active compounds, and the method enables us to achieve the easy separation of the products. See Scheme 1. 相似文献
58.
Shinya Oshita Akikazu Matsumoto 《复旦学报(自然科学版)》2005,44(5):913-914
We reported that layered polymer crystals are obtained by the topochemical polymerization of 1,3-diene monomers and provided as host material for organic intercalation. For intercalation using various long-alkyl amines as the guest species, its reaction behavior, mechanism, characteristics, and potential to application have been clarified. We also succeeded in the synthesis of several host layered polymer crystals with different tacticities and layer structures. We describe here intercalation using various stereoregular poly(muconic acid)s (PMA) and n-alkylamines as the host and guest compounds, respectively. The reaction behavior and the layered structure of the obtained ammonium polymers are discussed from the viewpoint of stereochemical structure of the host polymers. 相似文献
59.
1Introduction
Enzymatic kinetic resolution of racemic alcohols or esters is known as a useful method for the preparation of optically active secondary alcohols. However, the work-up including the separation of the mixture of the remaining substrate and the resulting compound spend a lot of time and waste much amount of solvents. On the other hand, organic synthesis based on polymer supports has made rapid progress. Although the methodology is potentially useful for the easy separation of compounds obtained by the enzymatic reaction, there have been relatively few reports on enzymatic resolutions of using a polymer so far. We have noticed that using a watersoluble polymer could be suitable for enzymatic transformation. Here, we report the first example of an enzyme-mediated enantioselective hydrolysis of poly(ethylene glycol)(PEG)-supported substrates with a carbonate moiety to afford optically active compounds, and the method enables us to achieve the easy separation of the products[1]. See Scheme 1. 相似文献
60.
1 Results Less-flammability is one of the most valuable properties of ionic liquids (ILs) comprised of perfluoroanions such as BF-4,TFSI-([(CF3SO2)2N]-).Recently,such a unique liquid has been expected to use as an electrolyte in order to improve thermal stability and longevity of a lithium secondary battery,which have been increasingly required for an application especially to an electric vehicle and a hybrid car.We previously reported that PI13[TFSI] (PI13: N-methyl-N-propylpiperidinium) could be used ... 相似文献