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1.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
2.
Purification and Characterization of Sucrose Synthase from Peach (Prunus persica) Fruit 总被引:4,自引:0,他引:4
Sucrose synthase (EC 2.4.1.13
[EC]
) was purified from peach fruit(Prunus persica) to a single band of protein on SDS-PAGE byammonium sulfate fractionation, DEAE-cellulose (DE-52) chromatography,Sepharose CL-6B gel filtration, PBA-60 affinity chromatographyand Sephadex G-200 gel filtration. The molecular weight wasestimated to be 360,000 by gel filtration. The enzyme was foundto be a tetramer of identical 87-kDa subunits. The maximum activityfor the synthesis and cleavage of sucrose was observed at pH8.5 and pH 7.0, respectively. The enzymatic reaction followedtypical Michaelis-Menten kinetics in both directions, with thefollowing parameters: Km(fructose), 4.8 mmM; Km(UDPglucose),0.033 mM; Km(sucrose), 62.5 mM; Km(UDP), 0.080 mM. Other properties,such as substrate specificity and the effects of divalent cations,were also investigated. The relationship between the enzymeand the accumulation of sucrose in peach fruit is discussed.
Present address: Laboratory of Horticulture, Faculty of Agriculture,Nagoya University, Chikusa, Nagoya 464, Japan. (Received May 2, 1988; Accepted September 14, 1988) 相似文献
3.
An alkaline solution of bismuth subnitrate reacted well with the cell membranes and cell walls of formaldehyde-glutaraldehyde potassium permanganate fixed Alternaria spores, demonstrating them with greater contrast than in sections stained with uranyl acetate and lead citrate. Optimal fine structure of fungal spores was obtained by en bloc staining with alkaline bismuth solution after aldehyde and permanganate fixation. The contrast of the cell organelles and cell walls was high enough in sections cut after the alkaline bismuth en bloc stain for direct ultrastructural observation. Our results indicate that the alkaline bismuth stain is useful either as an en bloc or section stain for aldehyde and permanganate fixed fungal spores. 相似文献
4.
5.
The uptake of sorbitol into vacuoles from immature flesh ofapple fruit (Maluspumila Mill, var domestica Schneid.) was facilitatedby 106 M ABA, while such uptake into protoplasts wasnot stimulated. By contrast, the application of 105 MIAA facilitated uptake of sorbitol into protoplasts but didnot significantly into vacuoles. (Received July 17, 1990; Accepted December 25, 1990) 相似文献
6.
A survey of oligotrophic Lake Rara, the biggest lake in Nepal, was carried out from 1982 till 1984. Mean depth is 100 m, and
maximum depth is 167 m. The surface area covers 9.8 km2, and the lake contains 0.98 km3 volume of water.
Transparency was about 16 m, photoquantum yield decreased exponentially with depth below 5 m, and the extinction coefficient
was 8.3 × 10−2. The concentration of Chl.-a was in the range of 0.06–0.46 mg m−3, and total nitrogen was 18–30 μg 1−1. The whole water column was well oxygenated. Primary productivity was extremely low. It has more than 30 inflowing brooks
and one outlet. The water quality of the brooks changes drastically with their location. The pH, electrical conductivity,
and EDTA hardness in the waters from a landslide area were high. In the waters from a rich pine forest they were extremely
low.
The zooplankton consisted of two species of protozoa, five species of rotifers, two species of Cladocera, and two species
of Copepoda. The zooplankton density range was 6200–16200 individuals m−3. The minimum was on November 11th, 1983 and the maximum on August 19th, 1983. 相似文献
7.
Multiple gene-like sequences related to the rabbit hepatic progesterone 21-hydroxylase cytochrome P-450 1 总被引:10,自引:0,他引:10
R H Tukey S Okino H Barnes K J Griffin E F Johnson 《The Journal of biological chemistry》1985,260(24):13347-13354
Rabbits exhibit phenotypic differences, 21H and 21L, in the rate of hepatic progesterone 21-hydroxylation that reflect 10-fold higher microsomal concentrations of cytochrome P-450 1 in 21H rabbits. A cDNA library in pBR322 was prepared from liver mRNA isolated from a 21H rabbit. A clone, p1-8, producing a hybrid protein resulting from the insertion of the cDNA into the beta-lactamase gene of the plasmid expressed 5 distinct epitopes that were recognized by a panel of monoclonal antibodies developed toward P-450 1. RNAs selected from total hepatic mRNA by filter hybridization with p1-8 yield at least two electrophoretically distinct proteins when translated in vitro and immunoprecipitated with the 3C3 monoclonal antibody. Only one of the two proteins is recognized by the 1F11 monoclonal antibody, which is highly specific for P-450 1, and the immunoprecipitated protein exhibits the electrophoretic mobility of P-450 1. The other protein remains unidentified. Northern blot analysis indicates that the 3' noncoding portion of p1-8 hybridizes to higher steady state concentrations of polyadenylated RNA in the 21H as compared to 21L rabbits. This correspondence in expression with that of P-450 1 in the 21H and 21L phenotypes further suggests that p1-8 encodes P-450 1 or a closely related protein. The cDNA is 1871 base pairs in length and encodes a protein of 487 amino acids. Southern blot analysis indicates that several independent, gene-like sequences hybridize with the 3' noncoding region of p1-8 under conditions of high stringency. These results indicate that P-450 1 is a member of an extensive multigene family. 相似文献
8.
Nitric Oxide Reversibly Suppresses Xanthine Oxidase Activity 总被引:10,自引:0,他引:10
Masami Fukahori Kohji Ichimori Hideyuki Ishida Hiroe Nakagawa Haruka Okino 《Free radical research》1994,21(4):203-212
The effects of nitric oxide (NO) on xanthine oxidase (XOD) activity and the site(s) of the redox center(s) affected were investigated. XOD activity was determined by superoxide (O2-) generation and uric acid formation. NO reversibly and dose-dependently suppressed XOD activity in both determination methods. The suppression interval also disclosed a dose-dependent prolongation. The suppression occurred irrespective of the presence or absence of xanthine; indicating that the reaction product of NO and O2-, peroxynitrite, is not responsible for the suppression. Application of synthesized peroxynitrite did not affect XOD activity up to 2 μM. Methylene blue, which is an electron acceptor from Fe/S center, prevented the NO-induced inactivation. The results indicate that NO suppresses XOD activity through reversible alteration of the flavin prosthetic site. 相似文献
9.
NADP+-Dependent Sorbitol Dehydrogenase Found in Apple Leaves 总被引:1,自引:0,他引:1
An NADP+-dependent sorbitol dehydrogenase that catalyzes sorbitoland glucose was found in apple leaves. The partially purifiedenzyme had optimum activity at pH 9.6 and a Km value of 128mM for sorbitol. Among the polyols studied, this enzyme showedthe most activity for sorbitol.
1This paper is contribution A-173 of the Fruit Tree ResearchStation. (Received June 4, 1984; Accepted July 31, 1984) 相似文献
10.
Subcellular Localization of Sorbitol-6-phosphate Dehydrogenase in Protoplast from Apple Cotyledons 总被引:1,自引:0,他引:1
The subcellular localization of sorbitol-6-phosphate (S6P) dehydrogenasein protoplasts of apple cotyledons was examined by differentialcentrifugation and linear sucrose density gradient centrifugation(3060%, w/w). The distribution of S6P dehydrogenase activitywas 55% in the 500 x g pellet of the homogenate and 35% in thesupernatant of 105,000 x g. When the x g pellet was recentrifugedin a linear sucrose density gradient, one major peak of activitywas found at a density of 1.23. This peak coincided with themajor peak of chlorophyll and NADP+-triose-P dehydrogenase activity.When the 500 x g pellet was sonicated, the major peak of S6Pdehydrogenase activity shifted to a lighter density (d=1.18).The shifted peak also coincided with the peak of chlorophyll.The enzyme detected in the major peak of chlorophyll (d=1.23)was partially solubilized by sonic or detergent treatment, butnot by hypotonic solution. The results supported the localizationof S6P dehydrogenase in chloroplasts, and presumably their associationwith thylakoid membranes. Part of the enzyme was assumed tobe naturally present in the cytosol, too. (Received November 4, 1980; Accepted January 21, 1981) 相似文献