全文获取类型
收费全文 | 531篇 |
免费 | 23篇 |
国内免费 | 2篇 |
出版年
2024年 | 1篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 22篇 |
2014年 | 27篇 |
2013年 | 32篇 |
2012年 | 28篇 |
2011年 | 28篇 |
2010年 | 15篇 |
2009年 | 22篇 |
2008年 | 31篇 |
2007年 | 34篇 |
2006年 | 35篇 |
2005年 | 44篇 |
2004年 | 43篇 |
2003年 | 37篇 |
2002年 | 34篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1976年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有556条查询结果,搜索用时 31 毫秒
11.
Katsuyuki Imai Atsushi Tanaka Ken Fujimori Masa-Oki Yamada 《Experimental cell research》1982,138(2):367-375
A neutral α-glucosidase (EC 3.2.1.20) activity was shown to be associated with granules which are sedimentable at 10 000 g after differential centrifugation of mouse peritoneal macrophage homogenates. When the post-nuclear supernatant was centrifuged in a sucrose density gradient, high activities for neutral α-glucosidase and β-glucuronidase (EC 3.2.1.31) were detected in the bottom fractions because of aggregation of the granules. Neutral α-glucosidase-containing granules were completely disaggregated by the addition of 20 units/ml of heparin and 10 mM Tris-HCl (pH 7.2), which caused only a partial disaggregation of β-glucuronidase-containing granules. The addition of a high concentration of heparin, Tris buffer, or KCl to the gradient gave the same patterns of disaggregation of the granules. Under the condition in which about 50% of the total β-glucuronidase activity was released into the medium, depending on phagocytosis, very little α-glucosidase was released. These observations suggested that neutral α-glucosidase may localize in non-lysosomal granules. 相似文献
12.
13.
Katsuyuki Nakano Sebastian P. Assenza Phyllis R. Brown 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,233(1):51-60
The reversed-phase mode of high-performance liquid chromatography was used to determine the intra- and inter-individual levels of UV-absorbing low-molecular-weight compounds in saliva. Many of the compounds known to occur in serum were also found in saliva; however, concentrations in saliva are lower. Both the intra- and inter-individual levels of these compounds vary significantly; in most cases, the inter-individual variance is 2–3 times the intra-individual variance.
Caffeine and its metabolites in saliva are also reported. A greater number of metabolites were found in the saliva of habitual coffee drinkers. After caffeine was administered orally, paraxanthine, theobromine, theophylline, 1-methylxanthine, and 1-methyluric acid were found in the saliva of an individual who did not drink coffee regularly. In this subject, the serum half-life for caffeine was 3.49 h and the saliva half-life was 3.27 h. The half-life of caffeine in an habitual coffee drinker who had refrained from caffeine products for four days was 4.39 h. 相似文献
14.
Summary Detailed histochemical studies have been conducted on the distribution of various enzymes such as thiamine pyrophosphatase,
α-glucan phosphorylase, hexokinase, glucose-6-phosphate dehydrogenase, aldolase, lactate dehydrogenase and succinate dehydrogenase
in various components of the nucleusEdinger-Westphali, nucleus n. oculomotorii, nucleus ruber and nucleus niger of healthy adult male Wistar strain rats.
The thiamine pyrophosphatase reaction showed the morphological patterns of the Golgi apparatus characteristic for each nucleus.
The Golgi apparatus was well developed in the nucleusEdinger-Westphali, composing a network of highly fenestrated plates in the nucleus n. oculomotorii and nucleus ruber, and a simple network
in the nucleus niger. These results indicate that the former three nuclei need a rich energy supply and argue against the
possibility that the four nuclei have a secretory role.
The neurons of the nucleusEdinger-Westphali may derive their energy mainly from glucose of the circulating blood, but glial cells may serve as energy donators to the
neurons in the pars compacta of the nucleus niger, and the neurons of the other nuclei may derive energy from both sources.
These conclusions are consistent with the morphological patterns of the Golgi apparatus.
It is suggested that the neurons of the nucleusEdinger-Westphali, nucleus n. oculomotorii, nucleus ruber and of the pars lateralis of the nucleus niger may be equipped almost equally with
the Embden-Meyerhof pathway and with the hexose monophosphate shunt. But, the hexose monophosphate shunt is dominant in the
pars compacta of the nucleus niger. It is also suggested that the pattern of distribution of succinate dehydrogenase may parallel
that of lactate dehydrogenase. The nucleus n. oculomotorii, and nucleus ruber have a higher level of oxidative metabolism
than the nucleusEdinger-Westphali and the nucleus niger. The nucleusEdinger-Westphali may be representative of autonomic nuclei with low oxidative metabolism whereas the nucleus n. oculomotorii may represent
motor nuclei with high oxidative metabolism. Predominance of hexose monophosphate shunt, intense hexokinase reaction around
the neurons, and weak activity of succinate dehydrogenase indicate that the pars compacta of the nucleus niger belongs to
the category of “exceptional nuclei”. 相似文献
15.
Katsuyuki Watanabe Kazuo Kimura Hirofuto Marumo Hirotoshi Samejima 《Bioscience, biotechnology, and biochemistry》2013,77(3):547-552
Alkali protease partially purified from a strain of Bacillus subtilis and yeast alcohol dehydrogenase were immobilized to weakly basic anion exchange resins using a bifunctional reagent, 2-carboxymethyIamino-4,6-dichloro-s-triazine.Properties of these immobilized enzymes were studied both in batchwise operation and in packed bed reactor systems. 相似文献
16.
Rika Kamei Mana Miyakoda Takahiko Tamura Daisuke Kimura Kiri Honma Kazumi Kimura Katsuyuki Yui 《Microbiology and immunology》2013,57(3):213-223
17.
Toshiko Kido Katsuyuki Tanizawa Kenji Inagaki Tohru Yoshimura Masaaki Ishida Katsumi Hashizume 《Bioscience, biotechnology, and biochemistry》2013,77(10):2549-2554
2-Nitropropane dioxygenase, purified to homogeneity by an improved method from a yeast, Hansenula mrakii, has a molecular weight of 42,000, and consists of a single polypeptide. The enzyme contains 1 mol of FAD per mol of enzyme. The iron protein associated with previous preparations was removed by the present purification procedures. The enzyme catalyzes the oxygenative denitrification of anionic nitroalkanes much more effectively than that of the neutral ones with the optimum pH of 6.5. The Michaelis constants for the anionic substrates are as follows: 2-nitropropane, 1.61 mM; 1-nitropropane, 3.23 mM; nitroethane, 3.13 mM, and 3-nitro-2-butanol, 0.59 mM. 相似文献
18.
19.
Yasuhiko Asada Katsuyuki Tanizawa Yoshiyasu Kawabata Haruo Misono Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(6):1513-1514
Soybean 7S and 11S globulins were stored at relative humidities (RHs) of 11% and 96% at 50°C. The redispersibility of the proteins at RH 96% decreased in a short time. However, it did not decrease, when stored for 45 days at RH 11%. Gel filtration showed that the proteins polymerized during storage. The effects of urea, sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) on the redispersibilities of the proteins at RH 96% showed that the hydrogen, hydrophobic and disulfide bonds participate in the polymerization of 7S globulin, and that the disulfide bond is strongly related to the polymerization of 11S globulin. Redispersibility was restored with 2-ME in both the 7S and 11S globulins and some of the proteins in the supernatant redispersed with 2-ME were observed to be similar to the native ones with respect to the gel filtration, electrophoretic behavior and circular dichroism spectrum. 相似文献
20.
Shinji Nagata Nobuyoshi Esaki Katsuyuki Tanizawa Hidehiko Tanaka Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(4):1137-1141
Two genes of Pseudomonas putida (IFO 12996) which code for enzymes participating in amino acid metabolism, were cloned in Escherichia coli C600 using pBR322 as a vector. pST7549 is a 7.9 kb hybrid plasmid DNA which is composed of four SalI fragments (0.3, 1.4, 1.9 and 4.3 kb), and codes for β-isopropylmalate dehydrogenase (EC 1.1.1.85) in l-leucine biosynthesis. The enzyme activity in the crude extract from E. coli C600 bearing pST7549 was 80 ~ 90% lower than that of E. coli K12 or P. putida. When the foreign SalI fragments derived from P. putida were subcloned, a 1.9 kb SalI fragment was found to encode β-isopropylmalate dehydrogenase and it did not contain the promoter of P. putida DNA. Plasmid pST6961 has a 1.8 kb insert derived from the P. putida DNA in the SalI site of pBR322. E. coli cells carrying this recombinant plasmid show no leucine racemase activity and no d-leucine transaminase activity, but five-times higher d-leucine oxidation activity than the host strain, E. coli. Enzymological studies have suggested that plasmid pST6961 codes for d-amino acid dehydrogenase, a key enzyme in d-amino acid metabolism. 相似文献