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61.
62.
Hanamura S Kiyono M Lukasik-Braum M Mlengeya T Fujimoto M Nakamura M Nishida T 《Primates; journal of primatology》2008,49(1):77-80
A flu-like disease spread among chimpanzees (Pan troglodytes schweinfurthii) of the M group at Mahale Mountains National Park, Tanzania, from June to July 2006. This epizootic or epidemic killed up
to 12 chimpanzees. The obvious evidence of their deaths came from finding the bodies of three infants who had previously shown
some symptoms of the disease. At least one of these infants died of pneumonia. In addition, nine chimpanzees were missing
after the outbreak. These individuals were assumed to have been killed by this epizootic because most of them had contact
with the infected individuals on the last days they were observed. We also found two dead bodies during this period, which
were thought to be those of two missing individuals. We confirmed 23 (35.4%) of 65 individuals of the M group showed some
symptoms of the disease, although most of them (20/23) did not die. More than half of them (14/23) had kin showing symptoms.
Since this epizootic may have been caused by contact with humans, it will be necessary to establish and follow appropriate
protocols for researchers, tourists, and park staff to observe chimpanzees, and to explore the mechanism of disease transmission
from humans to chimpanzees and among chimpanzees. 相似文献
63.
Motoo MotooShibata Masaru Uyeda Yutaka Kido Yuki Fujimoto Yuji Takano Yukie Yoshioka 《Bioscience, biotechnology, and biochemistry》2013,77(12):3377-3382
Streptomyces sp. No. B-1625, which was identified as a strain of Streptomyces antibioticus, is a typical producer of actinomycin, but also produces minor acidic antibiotic components (FA), besides actinomycins X2, D and X0β. The FA-components, which were obtained with a high-producing mutant, 11M-21, showed antibacterial and antitumor activities, and also similar visible and UV absorption spectra to those characteristic of actinomycin. The FA-components were separated into five components, FA1 FA2α, FA2β, FA3α and FA3β, on TLC. Among them, one component, FA3β, isolated in a purified state as an orange powder, has a composition of C, 52.97: H, 6.34: N, 10.48%, and is active against B. subtilis at a MIC of 5mcg/ml. The FA3β component showed pKa′ of 5.4 and 12.0 and λmax at 443, 427 and 233 nm. From these properties, FA3β is considered to be an acidic actinomycin congener. 相似文献
64.
65.
A transgenic class I antigen is recognized as self and functions as a restriction element 总被引:2,自引:0,他引:2
T Yoshioka C Bieberich G Scangos G Jay 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(11):3861-3867
The function of a transgenic Dd class I molecule in the induction of immunologic tolerance to major histocompatibility complex antigens and in directing major histocompatibility complex restriction in C57BL/6 mice were investigated. All of the transgenic Dd mouse strains were found to be tolerant for the Dd antigen. Spleen cells from transgenic mice were immunocompetent but consistently failed to generate an anti-Dd cytotoxic T lymphocyte response in vitro, and skin grafts between transgenic Dd mice were not rejected. These data suggests that the Dd antigen was recognized as a self molecule. In addition, the transgenic Dd mice generated antigen-specific Dd-restricted cytotoxic T lymphocyte, indicating that the Dd antigen also functioned as a restriction element for antigen recognition. These observations demonstrate the usefulness of the transgenic mouse system for studying class I antigen expression and function. 相似文献
66.
Kozi Asada Masa-aki Takahashi Mieko Nagate 《Bioscience, biotechnology, and biochemistry》2013,77(2):471-473
Allosamidin, a product of Streptomyces sp. No 1713, inhibited Bombyx mori chitinase specifically in a competitive way with a Ki o f about 0.1 μm. The effect of allosamidin on chitinases from r Streptomyces griseus and Serratia marcescens was weaker, about 1/500 that on B. mori chitinase. Allosamidin did not inhibit yam chitinase, lysozymes of hen egg-white or human urine, or B. mori α-N-acetyl-d-glucosaminidase. The results suggest that allosamidin is a specific inhibitor of the insect chitinase. 相似文献
67.
The structure for trichoclin, (E)-8-(3-methyl-4-hydroxy-2-butenyloxy)-psoralen, a new furocoumarin isolated from Trichocline incana, has been established. Phellopterin and isopimpinellin were also obtained. The new side chain of trichoclin was confirmed by synthesis. 相似文献
68.
l-threo-3,4-Dihydroxyphenylserine (DOPS) is a chiral unnatural β-hydroxy amino acid used for the treatment of Parkinson disease.
We developed a continuous bioconversion system for DOPS production that uses whole-cell biocatalyst of recombinant Escherichia coli expressing l-threonine aldolase (l-TA) genes cloned from Streptomyces avelmitilis MA-4680. Maximum conversion rates were observed at 2 M glycine, 145 mM 3,4-dihydroxybenzaldehyde, 0.75% Triton-X, 5 g E. coli cells/l, pH 6.5 and 10°C. In the optimized condition, overall productivity was 8 g/l, which represents 40 times the synthesis
yield possible with no optimization of conditions. 相似文献
69.
Robert S. Sparkes Hiroyuki Sasaki T. Mohandas Katsuji Yoshioka Ivana Klisak Yoshiyuki Sakaki Camilla Heinzmann Melvin I. Simon 《Human genetics》1987,75(2):151-154
Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1. 相似文献
70.
Kondou Y Higuchi M Takahashi S Sakurai T Ichikawa T Kuroda H Yoshizumi T Tsumoto Y Horii Y Kawashima M Hasegawa Y Kuriyama T Matsui K Kusano M Albinsky D Takahashi H Nakamura Y Suzuki M Sakakibara H Kojima M Akiyama K Kurotani A Seki M Fujita M Enju A Yokotani N Saitou T Ashidate K Fujimoto N Ishikawa Y Mori Y Nanba R Takata K Uno K Sugano S Natsuki J Dubouzet JG Maeda S Ohtake M Mori M Oda K Takatsuji H Hirochika H Matsui M 《The Plant journal : for cell and molecular biology》2009,57(5):883-894
Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23 000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis . This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources. 相似文献