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排序方式: 共有1276条查询结果,搜索用时 15 毫秒
1.
A preliminary report on the use of transfer factor for treating stage D3 hormone-unresponsive metastatic prostate cancer 总被引:4,自引:0,他引:4
Dr. Giancarlo Pizza Caterina De Vinci Diego Cuzzocrea Domenico Menniti Ernesto Aiello Paolo Maver Giuseppe Corrado Piero Romagnoli Ennio Dragoni Giuseppe LoConte Umberto Riolo Aldopaolo Palareti Paolo Zucchelli Vittorio Fornarola Dimitri Viza 《Biotherapy》1996,9(1-3):123-132
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have
suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA).
These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able
to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one
intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission
was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was
126 weeks, higher than the survival rates reported in the literature for patients of the same stage. 相似文献
2.
Giuliano Callaini Maria Giovanna Riparbelli Marcella Cintorino Sergio Antonio Tripodi Giorgio Bianciardi Piero Tosi Romano Dallai 《Biology of the cell / under the auspices of the European Cell Biology Organization》1994,81(1):39-45
Summary— Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo. 相似文献
3.
Andrea Lami Aldo Marchetto Piero Guilizzoni Anselma Giorgis Julieta Masaferro 《Hydrobiologia》1994,274(1-3):57-64
Stratigraphic analyses of organic carbon, organic nitrogen and algal and bacterial carotenoids in short cores of profundal
sediments of four alpine lakes (Tovel, Leit, Paione superiore and Tom) were used to reconstruct their trophic history. In
addition, depth distribution of carbonaceous particle concentrations provided information on lake contamination from atmospheric
deposition.
In three lakes (Tovel, Leit and Tom), sedimentary carotenoids unique to sulfur photosynthetic bacteria (okenone and isorenieratene)
provide evidence of changes in the oxygen, light and sulfide conditions in the water column. All the lakes are oligotrophic
or moderately productive, and the algal community is dominated by Chlorophyta, Pyrrhophyta and Cryptophyta. Cyanobacteria
are rather poorly represented.
The steep increase of carbonaceous particles in the uppermost sediment layers of all the lakes suggests that lake contamination
by atmospheric transport of pollutants began in the 1940s to 1950s. These data, coupled with those from a parallel study on
Chrysophycean scale-inferred pH, indicate recent acidification in those which are poorly buffered (Paione superiore and Leit). 相似文献
4.
A circular dichroism-based detection system presents several advantages in the HPLC analysis of chiral compounds because of the selective monitoring of optically active molecules. Its use allows reliable determination of enantiomeric excesses and elution order. To this end, the application of empirical, semiempirical, and nonempirical methods to get stereochemical information from the CD signal is reported. Furthermore, recording the CD spectra on line and evaluation of the dissymetry factor make the CD detection very powerful in characterizing the stereochemistry of chiral eluates. 相似文献
5.
Dihydroflavonol 4-reductase (DFR, EC 1.1.1.219) catalyzes the reduction of dihydroflavonols to leucoanthocyanins, a key "late" step in the biosynthesis of anthocyanins. In this study we showed that a strong reduction in DFR expression occurs in the non-red orange cultivar (Navel and Ovale) compared to that of the red orange (Tarocco) suggesting that the enzyme could be involved in the lack of production of anthocyanins. Therefore, we isolated and compared the cDNAs, the genomic clones, as well as the promoter regions of blood and blond orange dfrs. Our data revealed that the cDNA sequences of pigmented and non-pigmented orange DFRs were 100% homologous and contained a 1017 bp open reading frame which encodes a protein of 338 amino acid residues, corresponding to a molecular mass of 38010.76 Da, with a theoretical pI of 5.96. Moreover, we found that there were no significant differences in non-coding regions (introns and 5' upstream region) of dfr sequences. Southern blot analysis of genomic DNA indicated that dfr was present as a single copy gene in both cultivars. From these findings the low expression level of blond orange dfr, which might play a role in the phenotypic change from blood to blond orange, is thought to be the result of a likely mutation in a regulatory gene controlling the expression of dfr. In addition, here we reported the successful expression of orange DFR cDNAs leading to an active DFR enzyme which converts dihydroquercetin to leucoanthocyanidin, thus confirming the involvement of the isolated genes in the biosynthesis of anthocyanins. Moreover, as far as we know, this is the first report concerning the in vitro expression of DFR from fruit flesh whose biochemical properties might be very different from those of other plant organ DFRs. 相似文献
6.
Laura Borello Mario Ferraro Piero Penengo Maria Lia Rossotti 《Biological cybernetics》1981,39(2):79-85
In this paper we propose a model of visual perception in which a positive feedback mechanism can reproduce the pattern stimulus on a neurons screen. The pattern stimulus reproduction is based on informations coming from the spatial derivatives of visual pattern. This information together with the response of the feature extractors provides to the reproduction of the visual pattern as neuron screen electric activity. We simulate several input patterns and prove that the model reproduces the percept. 相似文献
7.
Comprehensive analysis of NAC family genes in Oryza sativa and Arabidopsis thaliana. 总被引:5,自引:0,他引:5
8.
Piero Morseletto 《Journal of Industrial Ecology》2020,24(4):763-773
The most recognized definition of the circular economy is that it is a restorative and regenerative economy. Despite the wide use and importance attributed to the concepts of “restoration” and “regeneration,” they are rarely defined or explained in the circular economy literature. In this context, this study critically examines the two terms, while providing guidance on their future utilization and development. Specifically, the study investigates the origin of the concepts, their adoption in frameworks that anticipated the idea of the circular economy, and their connotations in the circular economy literature. The examination supports the need for clear and distinct definitions, combined with precision in usage. From a review of the literature, restoration is a better‐defined concept than regeneration, although it needs conceptual re‐enforcement relative to the biological/ecological aspects of the circular economy. This study suggests looking in the direction of restoration ecology, a well‐established branch of ecological research. Conversely, regeneration is a symbolic/evocative term with little practical application in the context of circular systems except in the case of certain agricultural practices. Until new conceptual developments intervene, regeneration does not seem to be applicable to the economy as a whole and because of this, might be abandoned as a guiding principle of the circular economy. Unlike regeneration, restoration can be considered a core principle because it has widespread application and can be a point of reference for circular applications. This does not preclude the possibility that other concepts may be needed to augment restoration. 相似文献
9.
Andrea Caddeo Kristina Hedfalk Stefano Romeo Piero Pingitore 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2021,1866(5):158891
Human membrane bound O-acyltransferase domain-containing 7 (MBOAT7), also known as lysophosphatidylinositol acyltransferase 1 (LPIAT1), is an enzyme involved in the acyl-chain remodeling of phospholipids via the Lands' cycle. The MBOAT7 rs641738 variant has been associated with the entire spectrum of fatty liver disease (FLD) and neurodevelopmental disorders, but the exact enzymatic activity and the catalytic site of the protein are still unestablished.Human wild type MBOAT7 and three MBOAT7 mutants missing in the putative catalytic residues (N321A, H356A, N321A + H356A) were produced into Pichia pastoris, and purified using Ni-affinity chromatography. The enzymatic activity of MBOAT7 wild type and mutants was assessed measuring the incorporation of radiolabeled fatty acids into lipid acceptors.MBOAT7 preferentially transferred 20:4 and 20:5 polyunsaturated fatty acids (PUFAs) to lysophosphatidylinositol (LPI). On the contrary, MBOAT7 showed weak enzymatic activity for transferring saturated and unsaturated fatty acids, regardless the lipid substrate. Missense mutations in the putative catalytic residues (N321A, H356A, N321A + H356A) result in a loss of O-acyltransferase activity.Thus, MBOAT7 catalyzes the transfer of PUFAs to lipid acceptors. MBOAT7 shows the highest affinity for LPI, and missense mutations at the MBOAT7 putative catalytic dyad inhibit the O-acyltransferase activity of the protein. Our findings support the hypothesis that the association between the MBOAT7 rs641738 variant and the increased risk of NAFLD is mediated by changes in the hepatic phosphatidylinositol acyl-chain remodeling. Taken together, the increased knowledge of the enzymatic activity of MBOAT7 gives insights into the understanding on the basis of FLD. 相似文献
10.
Vanessa Pitozzi Stefania Pallotta Manuela Balzi Marta Bucciolini Aldo Becciolini Piero Dolara 《Free radical research》2013,47(11):1149-1154
We used X-rays from a linear accelerator and from a low energy therapeutic source to calibrate the single cell gel electrophoresis (comet assay), a widely used method to measure DNA damage. γ-Rays from 60Co, with known efficiency in inducing DNA breakage, were used as reference. Human lymphocytes and one murine tumour cell line, F10-M3 cells, were irradiated under different experimental conditions. A similar relationship between radiation dose and induced DNA damage was obtained with γ- and X-rays. A calibration curve was constructed to convert the comet assay raw data into break frequency. The median levels of DNA breaks and oxidative damage in circulating lymphocytes from healthy volunteers were calculated to be 0.76 and 0.80 breaks/109 Da, respectively, (0.50 and 0.52 breaks/106 bp). The values of oxidative DNA damage were in the same order of magnitude as those found by others with HPLC methods. 相似文献