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排序方式: 共有1015条查询结果,搜索用时 671 毫秒
981.
982.
Lymphatic invasion and metastasis. 总被引:4,自引:0,他引:4
983.
Zusammenfassung Es wird eine neue Methode zur selektiven Färbung beschädigter (toter) Hefezellen mit Hilfe eines Gemischs von Uranylnitrat und Ponceau-Rot beschrieben, die grosse praktische Vorteile gegenüber der klassischen Methylenblau- und Nilblaufärbung besitzt. 相似文献
984.
Amino-acid substitutions at codon 13 of the N-ras oncogene in human acute myeloid leukaemia 总被引:1,自引:0,他引:1
J L Bos D Toksoz C J Marshall M Verlaan-de Vries G H Veeneman A J van der Eb J H van Boom J W Janssen A C Steenvoorden 《Nature》1985,315(6022):726-730
DNAs from four out of five patients with acute myeloid leukaemia (AML) tested by an in vivo selection assay in nude mice using transfected mouse NIH 3T3 cells were found to contain an activated N-ras oncogene. Using a set of synthetic oligonucleotide probes, we have detected a mutation at codon 13 in all four genes. The same codon is mutated in an additional AML DNA that is positive in the focus-formation assay on 3T3 cells. DNA from the peripheral blood of one patient in remission does not contain a codon 13 mutation. 相似文献
985.
A method is described for the determination of glutamate oxaloacetate transaminase (GOT) activity in sperm plasma from boars and bulls as a test for fertilizing ability. 相似文献
986.
In contrast to the reported effects of polyamines on the high affinity neurotransmitter uptake, two polyamine-like spider toxins significantly increase the high affinity uptake of glutamate as demonstrated with high resolution autoradiography. The effects of both spider toxins were compared to those of a polyamine toxin from the wasp Philanthus triangulum, which is known to inhibit the high affinity glutamate uptake. 相似文献
987.
988.
H. A. S. van den Brenk Dana Jamieson 《Cellular and molecular life sciences : CMLS》1967,23(4):302-303
Zusammenfassung Männliche Ratten zeigen nach einmaliger oder wiederholter stark erhöhter O2-Zufuhr (3–5 at) Krämpfe und Lungenschäden und zum Teil Absterben. Schädigungen der Spermatogenese oder der Fertilität traten nicht auf. 相似文献
989.
T. Postmes A. E. van den Bogaard M. Hazen 《Cellular and molecular life sciences : CMLS》1995,51(9-10):986-989
Unprocessed honey is a recognized wound-healing remedy. However, to make clinical use of honey acceptable, it should be sterile. To find the lowest dose of irradiation needed for sterilization, six batches of honey (a?f) were gamma irradiated with 6, 12, 18, 22 and 25 kGy Cobalt-60. After a dose of 25 kGy the antibacterial activity was not altered. Presumably glucose oxidase (EC 1.1.3.4), which produces hydrogen peroxide, is not easily damaged by irradiation. Amylase activity on the other hand was significantly reduced to 19%, 19%, 21%, 22%, 43% in batchesa), b), c), d) andf) respectively, whereas no decrease was observed in batche). All batches spiked with approximately 106 spores fromCl. botulinum orB. subtilis per 50 g honey proved to be sterile after irradiation with a dose of 25 kGy. Honey was also spiked withCl. botulinum at up to 5000 spores per 50 g honey which is the upper limit of natural contamination. The sterilizing dose in this case was 18 kGy. 相似文献
990.
A tobacco mosaic virus-induced tobacco protein is homologous to the sweet-tasting protein thaumatin 总被引:4,自引:0,他引:4
Infection of tobacco plants with tobacco mosaic virus (TMV) results in an increase in the activities of several enzymes and induces the de novo synthesis of about 10 proteins that are protease-resistant and soluble at pH 3. These proteins accumulate in the intracellular leaf space. The appearance of pathogenesis-related (PR) proteins is closely associated with the phenomenon of 'systemic acquired resistance' and it has been suggested that such proteins have an antiviral function. Previously, we cloned complementary DNAs to the messenger RNAs for the three smallest PR proteins, PR-1a, -1b and -1c, and these clones were used to show that there is an increase of more than 100-fold in the concentration of PR-1 mRNAs following TMV infection of tobacco. Here, we describe the cDNA cloning of another mRNA whose synthesis is induced by TMV infection. Sequencing of the cDNA showed that the encoded protein is highly homologous to thaumatin, the intensely sweet-tasting protein from the fruits of the monocot Thaumatococcus daniellii Benth, a West African rainforest shrub. The conservation of a gene encoding a thaumatin-like protein in tobacco suggests that the encoded protein may have a more general function than that of being sweet-tasting. 相似文献