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141.
G. R. Pettit L. E. Houghton N. H. Rogers R. M. Coomes D. F. Berger P. R. Reucroft J. F. Day J. L. Hartwell H. B. Wood Jr. 《Cellular and molecular life sciences : CMLS》1972,28(4):381-382
Zusammenfassung Eine Voruntersuchung der Insektengruppe Lepidoptera auf anti-tumor-aktive Stoffe führte zu einer detaillierten chemischen Prüfung der aus Asien stammenden SchmetterlingeCatopsilia crocale Cramer (Pieridae) undPieris rapae cruavora. Ein bedeutender Teil der Anti-Tumor-Aktivität scheint ihren Ursprung in der chemischen Substanz Isoxanthopterin zu besitzen.
The present contribution represents Part XXVII of the series Antineoplastic Agents. For Part XXVI refer toG. R. Pettit, J. F. Day, J. L. Hartwell andH. B. Wood, Nature, Lond.227, 962 (1970).
This investigation was supported by Public Health Service Research Grants No. CA-10612-01 to No. CA-10612-04 from the National Cancer Institute, and was presented in part at the American Chemical Society Meeting, Washington, D.C., September 1971. We are also grateful to the National Science Foundation for financial assistance (Grant numbers GB-4939 and GB-6979) used in obtaining the Atlas CH-4B and SM-1B mass spectrometers employed in this study. 相似文献
The present contribution represents Part XXVII of the series Antineoplastic Agents. For Part XXVI refer toG. R. Pettit, J. F. Day, J. L. Hartwell andH. B. Wood, Nature, Lond.227, 962 (1970).
This investigation was supported by Public Health Service Research Grants No. CA-10612-01 to No. CA-10612-04 from the National Cancer Institute, and was presented in part at the American Chemical Society Meeting, Washington, D.C., September 1971. We are also grateful to the National Science Foundation for financial assistance (Grant numbers GB-4939 and GB-6979) used in obtaining the Atlas CH-4B and SM-1B mass spectrometers employed in this study. 相似文献
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143.
A chemical switch for inhibitor-sensitive alleles of any protein kinase 总被引:32,自引:0,他引:32
Bishop AC Ubersax JA Petsch DT Matheos DP Gray NS Blethrow J Shimizu E Tsien JZ Schultz PG Rose MD Wood JL Morgan DO Shokat KM 《Nature》2000,407(6802):395-401
Protein kinases have proved to be largely resistant to the design of highly specific inhibitors, even with the aid of combinatorial chemistry. The lack of these reagents has complicated efforts to assign specific signalling roles to individual kinases. Here we describe a chemical genetic strategy for sensitizing protein kinases to cell-permeable molecules that do not inhibit wild-type kinases. From two inhibitor scaffolds, we have identified potent and selective inhibitors for sensitized kinases from five distinct subfamilies. Tyrosine and serine/threonine kinases are equally amenable to this approach. We have analysed a budding yeast strain carrying an inhibitor-sensitive form of the cyclin-dependent kinase Cdc28 (CDK1) in place of the wild-type protein. Specific inhibition of Cdc28 in vivo caused a pre-mitotic cell-cycle arrest that is distinct from the G1 arrest typically observed in temperature-sensitive cdc28 mutants. The mutation that confers inhibitor-sensitivity is easily identifiable from primary sequence alignments. Thus, this approach can be used to systematically generate conditional alleles of protein kinases, allowing for rapid functional characterization of members of this important gene family. 相似文献
144.
A VEGF-A splice variant defective for heparan sulfate and neuropilin-1 binding shows attenuated signaling through VEGFR-2 总被引:1,自引:0,他引:1
Cébe Suarez S Pieren M Cariolato L Arn S Hoffmann U Bogucki A Manlius C Wood J Ballmer-Hofer K 《Cellular and molecular life sciences : CMLS》2006,63(17):2067-2077
The development of functional blood and lymphatic vessels requires spatio-temporal coordination of the production and release
of growth factors such as vascular endothelial growth factors (VEGFs). VEGF family proteins are produced in multiple isoforms
with distinct biological properties and bind to three types of VEGF receptors. A VEGF-A splice variant, VEGF-A165b, has recently been isolated from kidney epithelial cells. This variant is identical to VEGF-A165 except for the last six amino acids encoded by an alternative exon. VEGF-A165b and VEGF-A165 bind VEGF receptors 1 and 2 with similar affinity. VEGF-A165b elicits drastically reduced activity in angiogenesis assays and even counteracts signaling by VEGF-A165. VEGF-A165b weakly binds to heparan sulfate and does not interact with neuropilin-1, a coreceptor for VEGF receptor 2. To determine
the molecular basis for altered signaling by VEGF-A165b we measured VEGF receptor 2 and ERK kinase activity in endothelial cells in culture. VEGF-A165 induced strong and sustained activation of VEGF receptor 2 and ERK-1 and −2, while activation by VEGF-A165b was only weak and transient. Taken together these data show that VEGF-A165b has attenuated signaling potential through VEGF receptor 2 defining this new member of the VEGF family as a partial receptor
agonist.
Received 31 May 2006; received after revision 26 June 2006; accepted 14 July 2006 相似文献
145.
Jaeger E Webb E Howarth K Carvajal-Carmona L Rowan A Broderick P Walther A Spain S Pittman A Kemp Z Sullivan K Heinimann K Lubbe S Domingo E Barclay E Martin L Gorman M Chandler I Vijayakrishnan J Wood W Papaemmanuil E Penegar S Qureshi M;CORGI Consortium Farrington S Tenesa A Cazier JB Kerr D Gray R Peto J Dunlop M Campbell H Thomas H Houlston R Tomlinson I 《Nature genetics》2008,40(1):26-28
We mapped a high-penetrance gene (CRAC1; also known as HMPS) associated with colorectal cancer (CRC) in the Ashkenazi population to a 0.6-Mb region on chromosome 15 containing SCG5 (also known as SGNE1), GREM1 and FMN1. We hypothesized that the CRAC1 locus harbored low-penetrance variants that increased CRC risk in the general population. In a large series of colorectal cancer cases and controls, SNPs near GREM1 and SCG5 were strongly associated with increased CRC risk (for rs4779584, P = 4.44 x 10(-14)). 相似文献
146.
Stephen L. Wood 《西北部美国博物学家》2011,46(3)
Pseudoxylechinus indicus is decribed as new to science from India. 相似文献
147.
148.
Binding of fluoresceinated lectins to normal and dinitrofluorobenzene treated human leucocytes 总被引:1,自引:0,他引:1
K. R. Madyastha P. R. Madyastha G. W. Wood 《Cellular and molecular life sciences : CMLS》1978,34(10):1349-1350
Summary Using fluoresceinated lectins we have shown the receptor distribution on normal human granulocytes and lymphocytes following tagging with 1-fluoro- 2, 4-dinitrobenzene (DNFB). DNP-tagged cells exhibited strong, smooth membrane staining and produced smaller patches dispersed uniformly over the entire cell surface.This work was supported by Grant CA 16503 from the National Cancer Institute.Acknowledgment. We thank Miss C. Pickett for technical help and Mrs E. Olson and N. Shear for secretarial assistance. 相似文献
149.
Intracellular recording methods were used to investigate the action of methylene blue on electrical behavior of myenteric neurons in guinea pig small intestine. The neurophysiological studies were done in parallel with studies on contractile activity of the intestinal musculature. Methylene blue depolarized the membranes, increased the input resistance, augmented excitability and reduced postspike hyperpolarizing potentials in AH/Type 2 myenteric neurons. These effects, with the exception of suppression of postspike hyperpolarization, were reversed by exposure to elevated calcium. The mechanism of action of methylene blue appeared to be suppression of calcium-dependent potassium conductance in the neuronal membranes. The neuronal action of methylene blue was manifest as a release of excitatory neurontransmitter substances which evoked contraction of the small intestinal longitudinal muscle. 相似文献
150.