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41.
Max Hayman 《The Western journal of medicine》1955,83(6):435-440
The one approach most favored for alcoholism by psychiatrists in Southern California who answered a questionnaire is membership in Alcoholics Anonymous. Ninety-nine per cent of them approved Alcoholics Anonymous, and 80 per cent had referred patients to the organization. Yet they believed only 10 per cent of the persons who join A.A. remain sober for over two years. This against the claim of A.A. that 60 per cent or more of their fellowship are recovered emphasized the pessimism of the psychiatrists questioned.Ninety per cent of the psychiatrists who replied said they do not treat alcoholics or that they limit the number or the type they will accept for treatment. They obtain recovery, they said, of 10 per cent of patients, improvement of 50 per cent, and the rest are unchanged.The emphasis in psychiatry is on elimination of the anxieties leading to alcoholism; in Alcoholics Anonymous the emphasis is on the strength to bear these anxieties. Ninety per cent of the replies received were in favor of clinics for alcoholics, and the respondents felt that governmental agencies should support these clinics. Under such circumstances psychiatrists would combine their abilities with psychologists, social workers and Alcoholics Anonymous. Thirty-five per cent of psychiatrists said they are willing to work in a clinic, the majority without recompense. 相似文献
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44.
Parallel mosaicism of supernumerary chromosomes and sex chromosomes in Echymipera kalabu (Marsupialia) 总被引:1,自引:0,他引:1
Echymipera kalabu (Peramelidae: Marsupialia) does not have the full chromosome complement in all its adult somatic tissues. The chromosomes missing are the Y-chromosome in the male and an X-chromosome in the female. The full complement is present in the corneal epithelium and the reproductive tissue. A parallel mosaicism to this exists with respect to small supernumerary chromosomes which are found in certain animals of this species. These supernumeraries must be subject to the same control system as that which is responsible for the elimination of the sex chromosomes. 相似文献
45.
Nili Raz Yael Danin-Poleg Ryan B. Hayman Yudi Bar-On Alex Linetsky Michael Shmoish Eva Sanjuán Carmen Amaro David R. Walt Yechezkel Kashi 《PloS one》2014,9(12)
Vibrio vulnificus is an aquatic bacterium and an important human pathogen. Strains of V. vulnificus are classified into three different biotypes. The newly emerged biotype 3 has been found to be clonal and restricted to Israel. In the family Vibrionaceae, horizontal gene transfer is the main mechanism responsible for the emergence of new pathogen groups. To better understand the evolution of the bacterium, and in particular to trace the evolution of biotype 3, we performed genome-wide SNP genotyping of 254 clinical and environmental V. vulnificus isolates with worldwide distribution recovered over a 30-year period, representing all phylogeny groups. A custom single-nucleotide polymorphism (SNP) array implemented on the Illumina GoldenGate platform was developed based on 570 SNPs randomly distributed throughout the genome. In general, the genotyping results divided the V. vulnificus species into three main phylogenetic lineages and an additional subgroup, clade B, consisting of environmental and clinical isolates from Israel. Data analysis suggested that 69% of biotype 3 SNPs are similar to SNPs from clade B, indicating that biotype 3 and clade B have a common ancestor. The rest of the biotype 3 SNPs were scattered along the biotype 3 genome, probably representing multiple chromosomal segments that may have been horizontally inserted into the clade B recipient core genome from other phylogroups or bacterial species sharing the same ecological niche. Results emphasize the continuous evolution of V. vulnificus and support the emergence of new pathogenic groups within this species as a recurrent phenomenon. Our findings contribute to a broader understanding of the evolution of this human pathogen. 相似文献
46.
A field trial was conducted at two sites in the savanna ecosystem of eastern Colombia to compare the effects of inoculation
with vesicular-arbuscular mycorrhizal fungi (VAMF) ofBrachiaria dictyoneura (a tropical grass), cassava (Manihot esculenta), the tropical forage legume kudzu (Pueraria phaseoloides) andSorghum sp., and two phosphate sources. The second stage of the trial studied the effect of these pre-crop treatments on the subsequent
growth, nutrition and VAM status of cowpea (Vigna unguiculata) andStylosanthes capitata in the following season, compared with both crops sown in native savanna.
Inoculation significantly increased the levels of VAM and plant yields in the early growth stages of all crops during the
first season, particularly with the rock phosphate (RP) source. The most significant increases were observed in the mycorrhiza-dependent
cassava and kudzu crops up to 15 weeks after sowing, and were associated with increased foliar uptake of P and Mg. The effectiveness
of the introduced inoculum was greater at the field site with a sandier soil.
In the second season the levels of VAM in roots of cowpea andS. capitata were all increased significantly in pre-cropped plots compared with a savanna control. The increased presence of VAM was
associated with significantly increased yields on plots previously sown to cassava, kudzu andSorghum sp. The data support the idea that increasing the VAMF inoculum potential of these acid-infertile soils by inoculation or
pre-crops can greatly increase the rate of establishment of mycorrhiza-dependent host plants. 相似文献
47.
Activation of c-erbB in avian leukosis virus-induced erythroblastosis leads to the expression of a truncated EGF receptor kinase. 总被引:11,自引:2,他引:9
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I Lax R Kris I Sasson A Ullrich M J Hayman H Beug J Schlessinger 《The EMBO journal》1985,4(12):3179-3182
Chicken erythroblastosis caused by avian leukosis virus (ALV) is thought to be mediated by activation of the c-erbB/EGF receptor oncogene by a promoter-insertion mechanism. Here we study the proteins expressed by two ALV-induced leukemias and compare them with the avian EGF receptor and with the oncogene product of avian erythroblastosis virus (v-erbB) which was shown to be a truncated EGF receptor. It appears that the two leukemias express truncated EGF receptors of slightly different sizes with intrinsic tyrosine kinase activity. Hence, acute and chronic retroviruses utilize a common pathway for transformation. Moreover, the proteins expressed in the leukemias are similar to the avian EGF receptor with respect to their phosphopeptide maps, suggesting that they do not carry the C-terminal deletion characteristic of v-erbB. 相似文献
48.
Complete amino acid sequence of human vitronectin deduced from cDNA. Similarity of cell attachment sites in vitronectin and fibronectin. 总被引:45,自引:0,他引:45
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cDNA clones for vitronectin, a cell adhesion-promoting plasma and tissue protein, were isolated from a lambda gt11 library containing cDNA inserts made from human liver mRNA. The library was screened with anti-vitronectin antibodies and the positive clones were further identified with synthetic oligonucleotide probes deduced from the partial amino acid sequence of vitronectin. Nucleotide sequence analysis showed that the largest insert was 1545 bp long and contained the whole sequence corresponding to plasma vitronectin. It showed that vitronectin contains the entire 44-amino acid somatomedin B peptide at its NH2 terminus and, near its COOH terminus, a 34-amino acid glycosaminoglycan binding site in which half of the amino acids are basic residues. Three potential carbohydrate attachment sites are present in the sequence. An Arg-Gly-Asp sequence, which has previously been shown to be the cell attachment site in fibronectin, was found in vitronectin immediately after the NH2-terminal somatomedin B sequence. No other homologies with fibronectin were found. The Arg-Gly-Asp sequence appears to constitute the cell attachment site of vitronectin, since it is in the region where we have previously localized the cell attachment site, its presence correlate with cell attachment activity among the insert-coded polypeptides, and because previous results have shown that synthetic peptides containing the Arg-Gly-Asp sequence inhibit the cell attachment function of vitronectin. The discovery of an Arg-Gly-Asp cell attachment site in a protein with a known cell attachment function emphasizes the general importance of this sequence in cell recognition. 相似文献
49.
Complete structure of the chicken alpha 2(VI) collagen gene 总被引:4,自引:0,他引:4
Type VI collagen is a hybrid molecule consisting of a short triple helix flanked by two large globular domains. These globular domains are composed of several homologous repeats which show a striking similarity to the collagen-binding motifs found in von Willebrand factor. The alpha 2(VI) subunit contains three of these homologous repeats termed D1, D2 and D3. We have isolated and characterized the entire gene for chicken alpha 2(VI) collagen. This gene, which is present as a single copy in the chicken genome, is 26 kbp long and comprises 28 exons. All exons can be classified in three groups. (a) The triple-helical domain is encoded by 19 short exons (27-90 bp) separated by introns of phase class 0. These exons are multiples of 9 bp and encode an integral number of collagenous Gly-Xaa-Yaa triplets. (b) The homologous repeats D1-D3 are encoded by one or two very long exons each (153-1578 bp). These exons are separated by introns of phase class 1. (c) The homologous repeats and the collagen sequence are linked to each other by three short adapter segments which are each encoded by a single exon (21-46 bp). The modular nature of the polypeptide is thus clearly reflected by the mosaic structure of its gene. The size of the exons and the phase class of the introns suggest that the alpha 2(VI) gene evolved by duplication and shuffling of two different primordial exons, one of 9 bp encoding a collagen Gly-Xaa-Yaa triplet and one of 600 bp encoding the precursor of the homologous repeats. 相似文献
50.
Utility of the white gene in estimating phylogenetic relationships among mosquitoes (Diptera: Culicidae) 总被引:2,自引:0,他引:2
The utility of a nuclear protein-coding gene for reconstructing
phylogenetic relationships within the family Culicidae was explored.
Relationships among 13 species representing three subfamilies and nine
genera of Culicidae were analyzed using a 762-bp fragment of coding
sequence from the eye color gene, white. Outgroups for the study were two
species from the sister group Chaoboridae. Sequences were determined from
clone PCR products amplified from genomic DNA, and aligned following
conceptual intron splicing and amino acid translation. Third codon
positions were characterized by high levels of divergence and biased
nucleotide composition, the intensity and direction of which varied among
taxa. Equal weighting of all characters resulted in parsimony and
neighboring-joining trees at odds with the generally accepted phylogenetic
hypothesis based on morphology and rDNA sequences. The application of
differential weighting schemes recovered the traditional hypothesis, in
which the subfamily Anophelinae formed the basal clade. The subfamily
Toxorhynchitinae occupied an intermediate position, and was a sister group
to the subfamily Culicinae. Within Culicinae, the genera Sabethes and
Tripteroides formed an ancestral clade, while the Culex-Deinocerites and
Aedes- Haemagogus clades occupied increasingly derived positions in the
molecular phylogeny. An intron present in the Culicinae- Toxorhynchitinae
lineage and one outgroup taxon was absent in the basal Anophelinae lineage
and the second outgroup taxon, suggesting that intron insertions or
deletions may not always be reliable systematic characters.
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