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971.
Ryosaku Nomi Osamu Nimi Toshinori Miyazaki Akihiko Matsuo Hozo Kiyohara 《Bioscience, biotechnology, and biochemistry》2013,77(8):973-978
A natural precursor (L) of streptomycin which had no antibiotic potency was obtained from mycelium suspension of Streptomyces griseus in glucose solution and was transformed to streptomycin by H enzyme obtained from mycelium of the organism. This transforming reaction was carried out most effectively at slightly alkaline pH and inhibited by inorganic phosphate and ethylenediaminetetraacetate. L component was considered to be a phosphorylated compound and liberation of the phosphoric acid was essential for L component to be transformed to streptomycin. This transformation was performed not only by H enzyme but also by intestinal alkaline phosphatase, although some difference in the reaction mechanism was supposed to be between those two enzymes. 相似文献
972.
Akihiko Matsuo Mitsuru Nakayama Shûichi Hayashi Shigejiro Yasuda 《Bioscience, biotechnology, and biochemistry》2013,77(12):2241-2242
Castasterone (1), teasterone (2), and 6-deoxocastasterone (3), as well as monoolein, monolinolein, and monopalmitin, have been identified in immature seeds of rice (Oryza sativa) as active principles in the rice lamina inclination bioassay. Castasterone, as well as monoolein and monopalmitin, were likewise identified in immature seeds of Perilla frutescens, while monopalmitin was identified as a major active principle in cultured cells of Nicotiana tabacum. It seems that the occurrence of monoglycerides in higher plants as biologically active principles might be a general feature. 相似文献
973.
β-Xylosidase was purified 25 fold from a culture filtrate by ammonium sulfate fractionation, DEAE-Sephadex chromatography, column electrophoresis, gel filtration on Biogel P-100, and isoelectric focusing. The purified β-xylosidase was found to be homogeneous on SDS (sodium dodecyl sulfate) polyacrylamide gel electrophoresis and on disc electrophoresis. A molecular weight of 101,000 was estimated by chromatography on Sephadex G-200, and 102,000 was obtained by SDS polyacrylamide gel electrophoresis. The purified p-xylosidase had an isoelectric point at pH 4.45, and contained 4.5% carbohydrate residue. The optimum activity for the enzyme was found to be at pH 4.5 and 55°C. The enzyme activity was inhibited by Hg2 +, and N-bromosuccinimide at a concentration of 1 x 10?3 m. The purified enzyme hydrolyzed phenyl β-d-xyloside (ko—13.0 sec”1), p-nitrophenyl β-d-xyloside (ko=2l.3 sec?1), o-nitrophenyl β-d-xyloside (ko = 22.2 sec?1), o-chlorophenyl β-d-xyloside (ko = 20.0 sec?1), p-methylphenyl β-d-xyloside (ko~9.0 sec?1), o-methylphenyl β-d-xyloside (ko= 10.7 sec?1), p-methoxyphenyl β-d-xyloside (ko=10.3 sec?1), o-methoxyphenyl β-d-xyloside (&;o=10.9 sec?1), xylobiose (ko = 36A sec?1), xylotriose (ko = 34.5 sec?1), xylotetraose (ko~HA sec?1), and xylopentaose (ko= 13.0 sec?1). On enzymic hydrolysis of phenyl β-d-xyloside, the reaction product was found to be β-d-xylose with retention of configuration. The purified p-xylosidase was practically free of α-xylosidase and β-glucosidase activities. 相似文献
974.
Yoichi Itakura Taiji Imoto Akio Kato Kazuyoshi Yagishita 《Bioscience, biotechnology, and biochemistry》2013,77(11):2237-2238
Thermonsenstivie division mutants were derived from Bacillus subtilis Marburg 168 thy trp2 by means of membrane filtration after nitrosoguanidine mutagenesis. Among them, ts42 requiring uracil for normal growth at 48°C was investigated.In the absence of uracil, the mutant cells grew normally at 37°C and stopped dividing after temperature shift to 48°C resulting in filaments of two to four times length of normal rods. The total cell number after temperature shift from 37 to 48°C, increased two to three fold in 90 min and remained constant thereafter. The viable count after the temperature shift to 48°C, increased 1.5 to 2 fold in initial 60 min and then decreased exponentially. A rapid restoration of colony forming ability was shown when the mutant cells were shifted back to the permissive temperature after 120 to 180 min of incubation at 48°C or when uracil was introduced to the culture at 48°C. This recovery of viability was partly observed even in the presence of chloramphenicol. The synthesis of RNA of this mutant was shown to decline 20 min after the temperature shift to 48°C whereas the syntheses of DNA and protein proceeded for more than 80 min at that temperature.No newly isolated uracil requiring mutants formed filaments in the medium lacking uracil or showed growth pattern like ts42. 相似文献
975.
Takashi Matsuo Nobushige Itaya Toshio Mizutani Nobuo Ohno Keimei Fujimoto Yoshitoshi Okuno 《Bioscience, biotechnology, and biochemistry》2013,77(1):247-249
Three fractions with nucleolytic activities were isolated from rice bran by DEAE-cellulose column chromatography and designated as RB-1, RB-2 and RB-3. RB-1, RB-2 and RB-3 had molecular weights of approximately 6,200, 35,000 and 14,500, respectively, by gel filtration. The main fraction (RB-3) was purified by Sephadex G-75 and CM-cellulose column chromatography. The pH optimum was 5.0. The nucleolytic activity of RB-3 was strongly inhibited by Cu2 + , while EDTA had no effect on the activity. Seventy-five percent of the original activity of RB-3 still remained after 16 minutes of heating at 100°C. It appeared to be an endonuclease which hydrolyzes yeast RNA to yield purine nucleotides. 相似文献
976.
Akira Ôbayashi Hiroshi Yorifuji Tetsuya Yamagata Tôru Ijichi Matsuo Kanie 《Bioscience, biotechnology, and biochemistry》2013,77(8):717-730
Cytochrome c, coenzyme Q and lactic dehydrogenase (l-lactate: NAD oxidoreductase, EC 1, 1, 1, 27) in Rhizopus oryzae were studied in order to investigate the connection between the mechanism of lactate formation and terminal respiration.Cytochrome c was extracted easily and in good yield by the addition of cetyltrimethyl ammonium bromide to mycelial suspensions. It was purified by calcium phosphate gel and Amberlite IRC-50 resin chromatography.Coenzyme Q was extracted with ethanol, purified by chromatography on silicic acid, and, following crystallization from a mixture of ethanol and methanol, was identified as coenzyme Q0.Lactic dehydrogenase was partially purified and some of its properties were investigated.Rhizopus oryzae at an early growth stage in shake culture produced almost no lactate. At this stage, the mycelia were rich in cytochrome c and FAD. On the contrary, those of later growth stages fermented a larger amount of the glucose to lactate and the contents of cytochrome c and FAD were lower than in the young mycelia.Surface cultures produced lactate at a rate very nearly equivalent to the rate of glucose consumption. Addition of zinc to the medium resulted in decreased lactate production, but no increase was observed in the mycelial content of either cytochrome c or FAD in this case. On the other hand, increased quantities of FMN were found in mycelia from shake or surface cultures when zinc was added. 相似文献
977.
978.
Tadashi Ohsumi Makoto Hatakoshi Hirosi Kisida Noritada Matsuo Isamu Nakayama Nobushige Itaya 《Bioscience, biotechnology, and biochemistry》2013,77(11):3197-3202
Oxime ethers containing a 4-phenoxyphenoxy group in the molecules were synthesized and their insect growth regulating (IGR) activities were studied. Of these new IGR’s, propionaldehyde oxime O-2-(4-phenoxyphenoxy)ethyl ether and propionaldehyde oxime O-2-(4-phenoxy-phenoxy)propyl ether were found to be most effective, having much higher activities than metho-prene against larvae of Culex pipiens pallens and Musca domestica by the immersion method and medium method, respectively. In addition, the effects of steric isomerism of these compounds were examined; their IGR activities were found to have a close relationship to the juvenile hor-mone activity by the Galleria wax test. 相似文献
979.
Chuang Liu Gang Lin Xiaoqiu Wang Taiji Wang Guoyao Wu Defa Li Junjun Wang 《The Journal of nutritional biochemistry》2013,24(6):954-959
Intrauterine growth restriction (IUGR) is a major problem in both humans and animals. The IUGR fetus has abnormal metabolism of nutrients in the liver. This study was conducted with comparative proteomic approach and biochemical analyses to test the hypothesis that IUGR alters the hepatic proteome in the fetal liver. Livers were obtained from IUGR and normal-weight fetal pigs at Day 110 of gestation. Twenty-two differentially expressed proteins in the liver were identified between IUGR and normal fetal pigs. These proteins participate in the intermediary metabolism of nutrients (including glucose, amino acids, protein, lipids, vitamins and minerals), oxidative stress, as well as cell structure and growth. Of particular interest, the IUGR fetus had a higher activity of glutamate oxaloacetate transaminase and a lower activity of lipoprotein lipase than the normal ones. These results indicate altered metabolism of nutrients, abnormal ammonia utilization, and reduced capacity for detoxification in the liver of IUGR fetus. Collectively, the findings have important implication for explaining low food efficiency and understanding the mechanism responsible for impaired growth in IUGR neonates. 相似文献
980.
Kazuyuki Aizawa Hidehiko Nakagawa Kazuya Matsuo Kodai Kawai Naoya Ieda Takayoshi Suzuki Naoki Miyata 《Bioorganic & medicinal chemistry letters》2013,23(8):2340-2343
Recent studies have shown that nitroxyl (HNO) (1HNO/3NO?), which is the one-electron-reduced form of nitric oxide (NO), has unique biological activities, especially in the cardiovascular system, and HNO-releasing agents may have therapeutic potential. Since few HNO donors are available for use under physiological conditions, we synthesized and evaluated a series of Piloty’s acid (PA) derivatives and evaluated their HNO-releasing activity under physiological conditions. N-Hydroxy-2-nitrobenzenesulfonamide (17) was the most efficient HNO donor among our synthesized PA derivatives, including the lead compound, 2-bromo-N-hydroxybenzenesulfonamide (2). The high HNO-releasing activity is suggested to be due to electronic and steric effects. Compound 17 may be a useful tool for biological experiments. 相似文献