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91.
Crosses between genotypically distinct thalli of the monoecious species Porphyra yezoensis were carried out using immature thallus fragments from green- and red-type color mutants and also wild-type thalli. As the genes governing the mutants are monogenic, recessive to the wild-type, and belong to the same linkage group, the degree of self-fertilization could be estimated based on the pigmentation of the resultant diploid conchocelis. The degree of self-fertilization in the cross between the green-type and the wild-type was 48.5–55.0%, and in the cross between the red-type and the wild-type was 45.1–56.5%. In the cross between the green- and red-type mutants, the degree of self-fertilization was 46.0–54.5% when the green-type was the female parent, and was 44.8–55.6% when the red-type was the female parent. 相似文献
92.
The improved methods for the preparation of valency hybrid hemoglobins, (α3+β2+)2 and (α2+β3+)2 were presented. The (α3+β2+)2 valency hybrid was separated from the solutions of partially reduced methemoglobin with ascorbic acid, by using CM 32 column chromatography. The (α2+β3+)2 valency hybrid was also isolated from hemoglobin solutions, which were partially oxidized with ferricyanide, by chromatography on CM 32 column. These valency hybrid hemoglobins were found to be single on isoelectric focusing electrophoresis. Present procedures are very simple and are suitable for the bulk preparation of (α3+β2+)2 and (α2+β3+)2 valency hybrids. 相似文献
93.
Effects of Phosphate in Medium on Protein Secretion in a Protein-Producing Bacterium, Bacillus brevis 47 总被引:2,自引:0,他引:2
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Norihiro Tsukagoshi Hidehiko Yamada Akio Tsuboi Shigezo Udaka 《Applied microbiology》1981,42(2):370-374
Bacillus brevis 47 secreted up to 1 mg of protein per ml in a chemically defined medium, depending on phosphate concentration. The composition of exoproteins was altered quantitatively by the concentration of external phosphate. Morphologically, B. brevis 47 showed a distinct three-layered cell wall structure and shed the outer two layers during growth. 相似文献
94.
Akio Ito Shin-ichi Hayashi Touho Yoshida 《Biochemical and biophysical research communications》1981,101(2):591-598
The participation of a cytochrome b5-like hemoprotein of outer mitochondrial membrane (OM cytochrome b) in the NADH-semidehydroascorbate (SDA) reductase activity of rat liver was studied. NADH-SDA reductase activity was strongly inhibited by antibodies against OM cytochrome b and NADH-cytochrome b5 reductase, whereas no inhibition was caused by anti-cytochrome b5 antibody. NADH-SDA reductase exhibited the same distribution pattern as OM cytochrome b-mediated rotenone-insensitive NADH-cytochrome c reductase activity among various subcellular fractions and submitochondrial fractions. Both activities were localized in outer mitochondrial membrane. These observations suggest that OM cytochrome b-mediated rotenone-insensitive NADH-cytochrome c reductase system participates in the NADH-SDA reductase activity of rat liver. 相似文献
95.
Izumi Nakashima Fumihiko Nagase Akio Matsuura Takashi Yokochi Nobuo Kato 《Cellular immunology》1980,52(2):429-437
We demonstrated that each of various polyclonal lymphocyte activators (PLA) exhibits two types of adjuvant action to initiate the carrier-specific helper T-cell response to otherwise nonimmunogenic antigen. Type 1 action was characterized as that to initiate the T-cell response to subcutaneous injection of soluble bovine γ-globulin (BGG), and type 2 as that to initiate the response to intravenous injection of aggregated BGG. Each of various PLA showed these two types of adjuvant action in a dissociated fashion. The capsular polysaccharide of Klebsiella pneumoniae (CPS-K) showed both types of action to the highest degrees. Lipopolysaccharide of Escherichia coli exhibited type 2 action as markedly as CPS-K, but failed to show type 1 action. Concanavalin A showed definite type 1 action, but not type 2 action. Polyadenylic-uridylic acid showed definite type 2 action, but not type 1 action. Type 1 and type 2 actions of dextran sulfate were minimal. A hypothetical view is presented to consider that type 1 adjuvant action is directed to two mutually independent sites whereas type 2 action is directed to one site. 相似文献
96.
Electron microscopic examination of the lung of mice infected with a virulent strain of M. bovis (Ravenel) revealed marked alterations in the alveolar epithelial cells, particularly Type 2 cells (granular pneumocytes), in addition to the development of interstitial and intra-alveolar granuloma. Unlike the feature in uninfected mice, more than one Type 2 epithelial cells were often found adjacent to one another within a single alveolus. Some of these cells showed mitotic figures. Their characteristic lamellar inclusions were morphologically altered. 相似文献
97.
Mice were infected by iv injection with a virulent strain of Mycobacterium bovis, Ravenel strain, to prepare specimens for electron microscopical observation of their intracellular morphology. Observation was made with ultra-thin sections of the granulomatous lungs at an advanced stage of infection. Many apparently intact bacterial cells were found intracellulary, and the majority of them had lipoidal inclusions enclosed by a membranous structure. Several layers of mycobacterial cell wall were discernible, including a fairly wide space of the electron-transparent zone just beneath the electrondense outmost layer. Mesosomes, nuclear material, small dense granules and cross wall were found in almost the same appearance as those reported of mycobacteria grown in vitro. The bacilli were located mainly within intact or damaged phagosomes which were often filled with amorphous material of various electron densities. 相似文献
98.
99.
Enzymes of the C4, C3 pathway and photorespiration have beenanalyzed for P. hians and P. milioides, which have chlorenchymatousbundle sheath cells in the leaves. On whole leaf extracts thelevels of PEP carboxylase are relatively low compared to C4species, RuDP carboxylase is typical of C3 species, and enzymesof photorespiratory metabolism appear somewhat intermediatebetween C3 and C4. Substantial levels of PEP carboxylase, RuDPcarboxylase, and photorespiratory enzymes were found in bothmesophyll and bundle sheath cells. Low levels of C4-acid decarboxylatingenzymes may limit the capacity for C4 photosynthesis in P. hiansand P. milioides. The results on enzyme activity and distributionbetween mesophyll and bundle sheath cells are consistent withCO2 fixation via C3 pathway in these two species.
1 This research was supported by the College of Agriculturaland Life Sciences, University of Wisconsin, Madison; and bythe University of Wisconsin Research Committee with funds fromthe Wisconsin Alumni Research Foundation; and by the NationalScience Foundation Grant BMS 74-09611. (Received September 16, 1975; ) 相似文献
100.
Akio Murakami 《Radiation and environmental biophysics》1976,13(3):187-195
Summary The physical induction of recombinational events has been studied in the female silkworm (Bombyx mori), in which crossing-over does not normally occur. Female silkworms heterozygous in the trans type of two egg-color genes,pe (V-0.0) andre (V-31.7), received a single dose of X-rays (1000 R) at various developmental stages. Then they were crossed to marked males homozygous for both genes. The results indicated that X-rays increase the occurrence of recombinational events in silkworm females from first instar larvae to late stage pupae. The spontaneous frequency of exchange type recombinants in the control series was 2.5 x 10–5, while after irradiation the frequency of these recombinants was up to 38.8 x10–5. The sensitive stage to X-ray-induced recombinational events was late stage larvae from fourth to fifth instar. Exchange (cross-over) type recombinants were about three times more frequent than interchange types among the 122 recombinants recovered. The biological significance of the present finding is discussed. 相似文献