全文获取类型
收费全文 | 274篇 |
免费 | 13篇 |
出版年
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2016年 | 10篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 20篇 |
2012年 | 17篇 |
2011年 | 13篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 19篇 |
2007年 | 17篇 |
2006年 | 15篇 |
2005年 | 19篇 |
2004年 | 29篇 |
2003年 | 18篇 |
2002年 | 16篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1959年 | 1篇 |
1925年 | 2篇 |
排序方式: 共有287条查询结果,搜索用时 15 毫秒
61.
62.
Mikio Kawamori Yasushi Morikawa Seigo Takasawa 《Applied microbiology and biotechnology》1985,22(3):235-236
Summary L-Sorbose, which is known as an inhibitor of -1,3-glucan synthesis in fungi, induces the production of cellulases in strains belonging to Trichoderma reesei. Especially, mutant strains PC-3–7 and X-31, which were obtained by several steps of mutation from QM 9414, have the most effective cellulase inducibility by L-sorbose comparing with other mutants of Trichoderma reesei. They synthesized cellulases effectively in liquid culture, whenever the alkaline treated sugarcane bagasse was used as a main carbon source for lowering the cost of cellulase production. 相似文献
63.
Erythronium japonicum (Liliaceae) inhabits deciduous mesic forests of Hokkaido, northern Japan. Myrmecochory of this species was investigated, especially the dispersal frequency, the effect of seed predators and the seed fall pattern. In the quadrat census using marked seeds of E. japonicum, the ant Myrmica kotokui frequently transported the seeds. However, the frequency of seed removal was low and most seeds were dispersed as little as 1 m or less. The spatial distribution of E. japonicum individuals was nearly random and most seedlings were established 5–20 cm away from the fertile plants, indicating that even this small scale of seed dispersal contributes to avoiding crowding of seedlings. Some arthropods, e.g. springtails, spiders and ticks, hindered seed dispersal by devouring elaiosomes and seeds. Although ground beetle species also damaged seeds and elaiosomes, a few of them exhibited seed removal behaviour. E. japonicum dropped their seeds not all at once but bit by bit, taking 3–6 days to drop all seeds. This seed-fall pattern was effective in raising the frequency of seed removal by ants and reducing seed predation by some arthropods. 相似文献
64.
Two new species ofConiochaeta, isolated from Japanese soils, are described and illustrated:C. cephalothecoides, which is characterized by dark brown ascomata clothed with short setae, cylindrical asci and ovoid to almond-shaped or pyriform ascospores with a longitudinal germ slit; andC. dumosa, which is characterized by dark brown ascomata clothed with short setae and dense hyphal hairs, cylindrical asci and ellipsoid-fusoid ascospores with a longitudinal germ slit. These species are distinguished from most species of the genus by the unique cephalothecoid peridium of their ascomata. The associated anamorphs of both species are assignable to the form-genusLecythophora. 相似文献
65.
Two new species ofHeleococcum (a cleistothecial nectrioid genus in the Hypocreaceae) are described and illustrated.Heleococcum alatosporum, isolated from Indonesian soil, is recognized by the production of salmon-colored ascomata, cylindrical asci, and hyaline, small, bicellular ascospores with walls that are verruculose and ornamented with longitudinal ridges.Heleococcum inapertum, isolated from Philippine soil, is characterized by yellow ascomata, clavate asci, and pale yellow, middle-sized, bicellular, verruculose to weakly striate ascospores surrounded with a hyaline sheath. Anamorphs of the new species are included inAcremonium. A key to the accepted species of the genus is provided. 相似文献
66.
In the Neotropical rainforest of Barro Colorado Island, Panama, social organization and behavior were observed in 2 primitive
attine ant species,Myrmicocrypta ednaella andCyphomyrmex rimosus. Both species took nutrients from mycelia on fungus (i.e. mycophagy), and from plant nectar and sap which they collected
outside the nest (i.e. phytophagy). They also obtained alimentary liquid by soliciting nestmates (i.e. stomodeal trophallaxis).
Queens and larvae were wholly mycophagous, while older workers were much dependent on nectar, sap and alimentary liquid and
younger workers were mostly mycophagous but only partly phytophagous.M. ednaella used wood chips as substrate for the fungus garden. Its fungus-growing behavior was similar to those hitherto observed in
other primitive attine species. In contrast, the behavior ofC. rimosus was unique in its utilization of crop liquid as a substrate. In the rainforest,C. rimosus workers frequently forage outside the nests to collect nectar and sap, most of which is probably regurgitated for fungus
cultivation. 相似文献
67.
Siddabasave Gowda B. Gowda Seigo Usuki Mostafa A. S. Hammam Yuta Murai Yasuyuki Igarashi Kenji Monde 《Journal of lipid research》2016,57(2):325-331
Sphingoid base derivatives have attracted increasing attention as promising chemotherapeutic candidates against lifestyle diseases such as diabetes and cancer. Natural sphingoid bases can be a potential resource instead of those derived by time-consuming total organic synthesis. In particular, glucosylceramides (GlcCers) in food plants are enriched sources of sphingoid bases, differing from those of animals. Several chemical methodologies to transform GlcCers to sphingoid bases have already investigated; however, these conventional methods using acid or alkaline hydrolysis are not efficient due to poor reaction yield, producing complex by-products and resulting in separation problems. In this study, an extremely efficient and practical chemoenzymatic transformation method has been developed using microwave-enhanced butanolysis of GlcCers and a large amount of readily available almond β-glucosidase for its deglycosylation reaction of lysoGlcCers. The method is superior to conventional acid/base hydrolysis methods in its rapidity and its reaction cleanness (no isomerization, no rearrangement) with excellent overall yield. 相似文献
68.
69.
Dongpei Li Seigo Usuki Brandy Quarles Michael H. Rivner Toshio Ariga Robert K. Yu 《ASN neuro》2016,8(5)
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of upper and lower motor neurons. Although the etiology of ALS is obscure, genetic studies of familiar ALS suggest a multifactorial etiology for this condition. Similarly, there probably are multiple causes for sporadic ALS. Autoimmune-mediated motor neuron dysfunction is one proposed etiology for sporadic ALS. In the present study, anti-glycolipid antibodies including GM1, GD1b, GD3, and sulfoglucuronosyl paragloboside (SGPG) were investigated in the sera of a large number of patient samples, including 113 ALS patients and 50 healthy controls, by means of enzyme-linked immunosorbent assay with affinity parametric complex criterion evaluation and thin-layer chromatography immunooverlay (immuno-TLC). Anti-SGPG antibodies were found in the sera of 13.3% ALS patients (15 out of 113). The highest titer reached 1:1600. The presence of anti-SGPG antibodies in the serum samples was also confirmed by immuno-TLC. Importantly, a multiple logistic regression analysis showed that the presence of anti-SGPG antibody was positively correlated with age (p < .01) and negatively correlated with ALS Functional Rating Scale score (p < .05). Moreover, the localization of SGPG-immunoreactivity on the motor neurons of rat spinal cord and a mouse motor neuronal cell line, NSC-34 was observed by an immunofluorescence method. These data suggest that SGPG could represent a specific pathogenic antigen in those ALS patients. The presence of anti-SGPG antibodies in the serum of ALS patients should represent a diagnostic biomarker of ALS, and it could reflect the severity of the disease. 相似文献
70.
Hironaka Kawasaki Seigo Sakaguchi Katsuhiko Arimura Toshitake Irisa Kikuo Tominaga Chisato Hirayama Hiroshi Ibayashi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1975,385(2)
The enzyme activity which conjugates sulfobromophthalein with glutathione was separated from rat liver supernate by Sephadex G-75 gel filtration, and assayed by two different methods; paper electrophoresis and spectrophotometry. The enzyme activity was found mainly in the second protein fraction, and less than 5% of the activity in the first or third protein fractions. In vitro mixtures of sulfobromophthalein, [3H]glutathione and rat liver supernate showed that the major part of [3H]glutathione was detected in the first and second protein fractions, and the remainder in the third protein fraction. Phenobarbital treatment caused an increase of the enzyme activity, sulfobromophthalein and [3H]glutathione, in the second protein fraction. 相似文献