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41.
The use of a tri-substituted acylhydrazine as an isostere of a tertiary amide was explored in a series of HCV NS5B thumb site II inhibitors. Direct replacement generated an analog with similar conformational and physicochemical properties. The series was extended to produce compounds with potent binding affinities and encouraging levels of cellular potency.  相似文献   
42.

Background

The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample.

Methods/Principal Findings

A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three- to five-fold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as “repetitive strain injury” (RSI).

Conclusions/Significance

The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively.  相似文献   
43.
A series of Schiff bases including N-benzylideneaniline (NBA) nuclei were prepared. The chemical products obtained were characterized by mass spectometry (APCI), 1H NMR, and IR spectroscopy in order to seek their cytotoxic and proliferation effects on human small lung (A549) and cervical (HeLa) cancer cell lines with biochemical assays. All of the synthesized compounds showed antiproliferative effects to different extents.  相似文献   
44.
Microorganisms associated with the stems and roots of nonnodulated (Nod(-)), wild-type nodulated (Nod(+)), and hypernodulated (Nod(++)) soybeans [Glycine max (L.) Merril] were analyzed by ribosomal intergenic transcribed spacer analysis (RISA) and automated RISA (ARISA). RISA of stem samples detected no bands specific to the nodulation phenotype, whereas RISA of root samples revealed differential bands for the nodulation phenotypes. Pseudomonas fluorescens was exclusively associated with Nod(+) soybean roots. Fusarium solani was stably associated with nodulated (Nod(+) and Nod(++)) roots and less abundant in Nod(-) soybeans, whereas the abundance of basidiomycetes was just the opposite. The phylogenetic analyses suggested that these basidiomycetous fungi might represent a root-associated group in the Auriculariales. Principal-component analysis of the ARISA results showed that there was no clear relationship between nodulation phenotype and bacterial community structure in the stem. In contrast, both the bacterial and fungal community structures in the roots were related to nodulation phenotype. The principal-component analysis further suggested that bacterial community structure in roots could be classified into three groups according to the nodulation phenotype (Nod(-), Nod(+), or Nod(++)). The analysis of root samples indicated that the microbial community in Nod(-) soybeans was more similar to that in Nod(++) soybeans than to that in Nod(+) soybeans.  相似文献   
45.
Eighteen isolates of anaerobic coryneforms from human bone marrow and skin and four type strains of Propionibacterium were studied chemically, biochemically and antigenically. All of the isolates were identified as Propionibacterium acnes; of the 18 isolates, 16 belonged to serotype I and two to serotype II. By means of gas liquid chromatography and mass spectral analysis, a large amount of iso-type fatty acids, such as iso-pentadecanoic and iso-heptadecanoic acids were detected in whole cells of isolates and type strains. Antitumor and adjuvant effects of the isolates and type strains were found to differ considerably among the strains. One of the isolates, P. acnes C-7, which showed potent biological activities was fractionated by hot phenol-water extraction. The resulting insoluble middle layer was found the most effective in tumor protection, adjuvant action in immune response and phagocytic activity in mice.  相似文献   
46.
The International Journal of Life Cycle Assessment - Social sustainability may be assessed using a variety of methods and indicators, such as the social footprint, social impact assessment, or...  相似文献   
47.
Alkaline phosphatase-conjugated oligonucleotide probes were developed to detect the gene coding for Vero toxin 1 (VT1) and Vero toxin 2 (VT2). Using these probes, 3 hr was enough to detect VT genes when suspicious colonies of enterohaemorrhagic Escherichia coli (EHEC) were obtained on an agar plate. The results of a hybridization test with 144 isolates of EHEC O157 and one isolate of Shigella dysenteriae Type 1 agreed exactly with the immunological detection, reversed passive latex agglutination (RPLA) test, of VTs in their culture supernatants. The sensitivity levels of these probes for the detection of VT genes were 100%. The specificity of these probes were also tested with a total of 1,002 strains of Escherichia coli other than EHEC and 8 strains of Shigella sp. other than Shigella dysenteriae Type 1; the results showed 100% specificity.  相似文献   
48.
Human erythrocytes incubated with an iron catalyst ADP-chelated Fe3+ undergo oxidative damage of the membrane including lipid peroxidation, protein oxidation, and protein aggregation, and become susceptible to recognition by human macrophages. In order to clarify the membrane components of macrophages responsible for the recogrution of the oxidized erythrocytes, binding of the oxidized cells to dot and Western blots of solubilized membrane of macrophages was investigated. The oxidized erythrocytes but not unoxidized cells bound to the dot blots. The binding was effectively inhibited by saccharide chains of band 3, a major glycoprotein of human erythrocytes, and lowered when the saccharide chains of band 3 were removed from the cell surface by pretreatment of the cells with endo-P-galactosidase which specifically cleaves the polylactosaminyl saccharide chains of band 3. The oxidized erythrocytes bound to the membrane proteins of macrophages with molecular mass of about 50, 80, and 120 kDa on Western blots depending on the saccharide chains of band 3 on their surface. The results suggest that the oxidatively damaged erythrocytes are specifically recognized by these proteins of macrophage membrane having saccharide binding ability.  相似文献   
49.
Coenzyme B(12) serves as a cofactor for enzymatic radical reactions. The essential steps in all the coenzyme B(12)-dependent rearrangements are two hydrogen abstraction steps: hydrogen abstraction of the adenosyl radical from substrates, and hydrogen back-abstraction (recombination) of a product-derived radical from 5'-deoxyadenosine. The energetic feasibility of these hydrogen abstraction steps in the diol dehyratase reaction was examined by theoretical calculations with a protein-free, simplified model at the B3LYP/6-311G* level of density functional theory. Activation energies for the hydrogen abstraction and recombination with 1,2-propanediol as substrate are 9.0 and 15.1 kcal/mol, respectively, and essentially not affected by coordination of the substrate and the radical intermediate to K+. Since these energies can be considered to be supplied by the substrate-binding energy, the computational results with this simplified model indicate that the hydrogen abstraction and recombination in the coenzyme B(12)-dependent diol dehydratase reaction are energetically feasible.  相似文献   
50.
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