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1.
PM Visscher 《遗传、选种与进化》1995,27(4):335-345
2.
Chromosome-specific subsets of human alphoid DNA identified by a chromosome 2-derived clone 总被引:3,自引:0,他引:3
Mariano Rocchi Antonio Baldini Nicoletta Archidiacono Shabnam Lainwala Orlando J. Miller Dorothy A. Miller 《Genomics》1990,8(4):705-709
We have cloned an alphoid DNA fragment, pBS4D, from the DNA of a human-hamster hybrid cell line containing chromosome 2 as its only cytologically detectable human component. Under high stringency conditions, pBS4D hybridized in situ mostly to chromosome 2 and to a lesser extent to chromosomes 18 and 20. Restriction analysis using the DNA from selected somatic hybrid cell lines revealed that the genomic organization of this alphoid DNA differs on each of these three chromosomes. 相似文献
3.
We describe a human genomic cosmid clone, 56.1.1, that contains subtelomeric sequences present on multiple human chromosomes. In particular, using fluorescence in situ hybridization, we have identified 16 sites of hybridization on 12 chromosomes. In a sample of 8 unrelated individuals, 10 of these sites showed interindividual variation. Co-hybridization with other polymorphic probes allowed us to demonstrate cytologically heterozygosity at three sites in six individuals. The chromosomal distribution of hybridization sites in a family strongly suggests that these variants are inherited in a Mendelian fashion. These data show that subtelomeric repeats are a rich source of genetic variability. Possible mechanisms of generation of such variants are discussed. 相似文献
4.
Mischarging Escherichia coli tRNAPhe with L-4'-[3-(trifluoromethyl)-3H-diazirin-3-yl]phenylalanine, a photoactivatable analogue of phenylalanine 总被引:4,自引:0,他引:4
The Boc-protected derivative of a photoactivatable, carbene-generating analogue of phenylalanine, L-4'-[3-(trifluoromethyl)-3H-diazirin-3-yl]phenylalanine [(Tmd)Phe], was used to acylate 5'-O-phosphorylcytidylyl(3'-5')adenosine (pCpA). A diacyl species was isolated which upon successive treatments with trifluoroacetic acid and 0.01 M HCl yielded a 1:1 mixture of 2'(3')-O-(Tmd)phenylalanyl-pCpA and of its 2'-5'-phosphodiester isomeric form. Adapting a procedure introduced by Hecht's group [Heckler, T.G., Chang, L.H., Zama, Y., Naka, T., Chorghade, M.S., & Hecht, S.M. (1984) Biochemistry 23, 1468-1473], brief incubation of a 15 molar excess of this material with Escherichia coli tRNAPhe, missing at the acceptor stem the last two nucleotides (pCpA), in the presence of T4 RNA ligase and ATP afforded "chemically misaminoacylated" tRNAPhe in approximately 50% yield. Following chromatographic purification on DEAE-Sephadex A-25, benzoylated DEAE-cellulose, and Bio-Gel P-6, the misaminoacylated tRNAPhe was characterized by (i) urea-polyacrylamide gel electrophoresis, (ii) enzymatic reaminoacylation under homologous conditions following chemical deacylation, and (iii) its ability to stimulate protein synthesis in an in vitro translation system which, through the addition of the phenylalanyl-tRNA synthetase inhibitor phenylalaninyl-AMP, was unable to charge its endogenous tRNAPhe. The data demonstrate that we have prepared a biologically active misaminoacylated tRNAPhe. 相似文献
5.
The beneficial effects of long acting somatostatin analogue SMS 201-995 in an acromegalic patient affected by severe diabetes mellitus are reported. Neither human insulin alone nor human insulin plus bromocriptine allowed satisfactory metabolic control though, with the latter treatment, virtually normal plasma GH levels were reached. Conversely, addition of SMS 201-995 to insulin treatment led to normalization of blood glucose. This result was obtained with a dose of SMS 201-995 of 400 micrograms/day and only after 3 weeks of therapy. 相似文献
6.
Summary rRNA gene activity was evaluated by cytologic methods in cultured human cells from two different tissues grown under controlled experimental conditions. The modal and average numbers of silver positive nucleolus organizers (NOs) per cell as well as the distribution of cells with different numbers of silver positive NOs and different combinations of D-plus G-group silver stained chromosomes, were evaluated. Statistically significant differences in the average number of silver positive NOs per cell between leukocytes and fibroblasts grown under standard experimental conditions have been demonstrated. The observed differences became sharper in cells cultured under more restrictive conditions. Also, differences in the frequency of silver positivity of specific chromosomal NOs located on individually indentified chromosomes were observed in cells from the same tissue. Furthermore, differences in the frequency of activation of rDNA clusters located on the same chromosome were also observed between cells from the two tissues. The possible biologic meanings of these findings are discussed.This paper is dedicated to Professor G. Montalenti on the occasion of his 80th birthday 相似文献
7.
P. Rizzu E. A. Lindsay C. Taylor H. O’Donnell A. Levy P. Scambler A. Baldini 《Mammalian genome》1996,7(9):639-643
We have identified and cloned a gene, ES2, encoding a putative 476 amino acid protein with a predicted M
r
of 52,568. The gene is localized within the DiGeorge/Velocardiofacial syndrome locus on 22q11.2 and is deleted in all the
patients in which a deletion within 22q11 could be demonstrated, with the exception of one patient. ES2 is expressed in all
the tissues studied. Sequence comparison showed identity with five ESTs and at the amino acid level the sequence was highly
similar to, and collinear with, a hypothetical C. elegans protein of unknown function. Mutation analysis was performed in 16 patients without deletion, but no mutation has been found.
The cDNA sequence is conserved in mouse and is localized on MMU16B1-B3, known to contain a syntenic group in common with HSA
22q11.2.
Received: 25 March 1996 / Accepted: 15 May 1996 相似文献
8.
E. Baldini Osvaldo Facini Fabrizio Nerozzi Federica Rossi Annalisa Rotondi 《Trees - Structure and Function》1997,12(2):73-81
Light partition has been examined and evaluated on five woody species (Olea europaea, Ficus carica, Pittosporum tobira, Hedera helix maculata, Persica vulgaris) in relation to their leaf morpho-histological characteristics, water and chlorophyll contents. Leaf parameters and optical
properties (reflectance, transmittance, absorbance) in PAR, FR and NIR wavebands (400–1100 nm) were preliminarily submitted
to a canonical correlation analysis where lamina thickness and water content showed a leading role in determining all the
optical properties, while chlorophyll, influential in the PAR region, was remarkably effective only in an extreme pigment
situation when green and albino patches of ivy leaves were compared. Transmittance appeared inversely related to lamina thickness
in accordance with the Lambert Beer law. Significant correlations were found also between mesophyll water content and both
transmittance (positive) and reflectance (negative). Olive leaves showed peculiar optical patterns because of the dense and
continuous trichome layer on their abaxial surface.
Received: 3 January 1997 / Accepted: 5 May 1997 相似文献
9.
Haploinsufficiency of cytosolic serine hydroxymethyltransferase in the Smith-Magenis syndrome. 总被引:2,自引:1,他引:1 下载免费PDF全文
S H Elsea R C Juyal S Jiralerspong B M Finucane M Pandolfo F Greenberg A Baldini P Stover P I Patel 《American journal of human genetics》1995,57(6):1342-1350
Folate-dependent one-carbon metabolism is critical for the synthesis of numerous cellular constituents required for cell growth, and serine hydroxymethyltransferase (SHMT) is central to this process. Our studies reveal that the gene for cytosolic SHMT (cSHMT) maps to the critical interval for Smith-Magenis syndrome (SMS) on chromosome 17p11.2. The basic organization of the cSHMT locus on chromosome 17 was determined and was found to be deleted in all 26 SMS patients examined by PCR, FISH, and/or Southern analysis. Furthermore, with respect to haploinsufficiency, cSHMT enzyme activity in patient lymphoblasts was determined to be approximately 50% that of unaffected parent lymphoblasts. Serine, glycine, and folate levels were also assessed in three SMS patients and were found to be within normal ranges. The possible effects of cSHMT hemizygosity on the SMS phenotype are discussed. 相似文献
10.
Insulin and nonhydrolyzable GTP analogs induce translocation of GLUT 4 to the plasma membrane in alpha-toxin-permeabilized rat adipose cells 总被引:14,自引:0,他引:14
G Baldini R Hohman M J Charron H F Lodish 《The Journal of biological chemistry》1991,266(7):4037-4040
Rat adipose cells treated with Staphylococcus aureus alpha-toxin are permeable and retain their ability to respond to insulin after hormone treatment. The GLUT 4 glucose transporter isoform, specific to fat and muscle cells, is translocated normally from low density microsomes to the plasma membrane in permeabilized cells. Addition of guanosine 5'-O-(3-thiotriphosphate), guanylyl imidodiphosphate, or guanylyl beta, gamma-methylenediphosphate to permeabilized adipocytes induces an insulin-like translocation of GLUT 4 to the plasma membrane; GTP or adenosine 5'-(beta, gamma-imino)triphosphate has no effect. No translocation of GLUT 4 is observed when GTP analogs are added to intact adipocytes. These results suggest the involvement of a GTP-binding protein in insulin-triggered recruitment of GLUT 4 to the cell surface. 相似文献