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101.
Ornella Piazza Simona Cotena Edoardo De Robertis Ferdinando Caranci Rosalba Tufano 《Neurochemical research》2009,34(7):1289-1292
The pathogenesis of sepsis associated encephalopathy (SAE) is not yet clear: the blood–brain barrier (BBB) disruption has
been indicated among the possible causative mechanisms. S100B, a calcium binding protein, originates in the central nervous
system but it can be also produced by extra-cerebral sources; it is passively released from damaged glial cells and neurons;
it has limited passage through the BBB. We aimed to demonstrate BBB damage as part of the pathogenesis of SAE by cerebral
spinal fluid (CSF) and serum S100B measurements and by magnetic resonance imaging (MRI). This paper describes four septic
patients in whom SAE was clinically evident, who underwent MRI and S100B measurement. We have not found any evidence of CSF-S100B
increase. Serum S100B increase was found in three out of four patients. MRI did not identify images attributable to BBB disruption
but vasogenic edema, probably caused by an alteration of autoregulation, was diagnosed. S100B does not increase in CSF of
septic patients; S100B increase in serum may be due to extracerebral sources and does not prove any injury of BBB. MRI can
exclude other cerebral pathologies causing brain dysfunction but is not specific of SAE. BBB damage may be numbered among
the contributors of SAE, which aetiology is certainly multifactorial: an interplay between the toxic mediators involved in
sepsis and the indirect effects of hyperthermia, hypossia and hypoperfusion. 相似文献
102.
103.
Elena Cassani Edoardo Bertolini Francesco Cerino Badone Michela Landoni Dario Gavina Alberto Sirizzotti Roberto Pilu 《Molecular breeding : new strategies in plant improvement》2009,24(4):375-385
The “green revolution” involving mainly wheat and rice was based on the use by breeders of semidominant mutations involved
in the signal transduction pathway of Gibberellin (GA). In particular, mutations in the Reduced height (Rht) gene of wheat have been used to reduce plant height and consequently to avoid storm damage and lodging. These genes have
been cloned and they encode for DELLA proteins which contain an N-terminal DELLA and a VHYNP domain essential for GA-dependent
degradation of these proteins. In maize several mutations have been isolated which affect gibberellin biosynthesis and perception
and in particular, mutations in Dwarf8 (D8) gene cause a severe dwarfing phenotype. D8 gene has been identified as an orthologue of Rht (Reduced height), Slr1(Slender rice 1) and Gibberellic Acid Insensitive (GAI) genes, this latter is a negative regulator of GA response in Arabidopsis. In this work, for the first time, we isolated and characterized a single amino acid insertion in the VHYNP domain of D8 maize gene causing the appearance of a dominant dwarf mutation. This spontaneous mutation, named D8-1023, showed a phenotype which is less severe in comparison with the other D8 mutants previously isolated which have modifications
in the DELLA domain. This mutant appears to be an useful tool either to study the mechanism of GA-modulated growth in plants
or to lower the height of maize tropical germplasm for breeding purposes. 相似文献
104.
Abstract Temperatures recorded in a olive-tree stem in 1961–1962. — In the Botanical Garden of Bari a temperature recorder has been placed, bearing 6 electrothermometers with platinum resistences having a sensitivity of 2,4 mm/C[ddot], with a recording approximation of 0,1 C[ddot]. The olive tree under examination is a grown-up tree, which has been pruned according to the local methode, and it belongs to a local breed named « Ogliarola leccese ». — Five thermometers have been employed as follows: 1rst in the air, hanging from the stem, m. 1,30, high; 2nd into the outer bark, cm, 0,5 deep; 3rd into the cambium, cm. 1,5 deep; 4th into the sap-wood, cm. 6 deep; 5th into the hearth-wood, cm. 22 deep. — The thermometers were all placed on the east side of the stem. — The figures and the graphs of the paper show that: a) The whole stem of the specimen under examination has a mean temperature which is higher than that of the surrounding air. b) The outer bark gets warmer than the air, during the day-time; during the night it gives up heat outside and inside, namely towards the stem tissues, particularly to the bark-cambium-sapwood zone, and also as far as the hearth wood zone. c) The whole living zone of the stem (bark-cambium-sapwood) generally keeps temperature values intermediate between those of the outer bark and those of the air. The temperature values vary along the year. d) In spring the cambium is warmer than the outer bark. e) In winter cambium and sapwood generally have the same temperature. The temperature values recorded in this season are much lower than those of the outer bark and almost the same of those of the air. f) The behaviour of temperature in cambium and sapwood is probably ruled by biological factors. g) The hearth-wood keeps generally warmer than the air and cooler than other outer tissues. Its thermic rhytm is almost reversed in comparison with that of the outer tissues. Il seems that hearth wood acts as an useful heat collector and distributor towards the living outer tissues during the diurnal and seasonal temperature remissions, at least in mild climates as that of Bari. 相似文献
105.
106.
Summary This paper is focused on the facies associations of an Early-Middle Norian stratigraphic succession cropping outin the Northern
Calabria (Buonvicino, Cosenza). These carbonate deposits, pertaining to the Verbicaro Unit, represent a dolomitized platform
characterized by a clear dominance of automicrites over skeletal metazoans.
On the basis of the chronostatigraphic data and sedimentary evolution, two stratigraphic units have been distinguished: the
Lower Unit (object of the present paper) and the Upper Unit. The Lower Unit consists of an Early-Middle Norian high-relief
prograding carbonate platform. The Upper Unit is represented by Middle p.p.-Upper Norian basinal deposits.
Three main facies associations, indicative of different depositional settings, have been identified.
The inner platform facies association is characterized by automicrite (cauliflower-columnar subordinate planar stromatolites)
associated with detrital carbonates (intraclastic breccia, bioclastic grainstone and packstone). Apeculiar facies is represented
by megalodontid-bearing beds. Mud-cracked horizons and low-developed teepees occur quite frequently.
The margin facies association is dominated by automicrite (planar to low relief stromatolites associated with thrombolitic
fenestral boundstone) and detrital carbonates with subaerial exposure features.
The slope facies association includes detrital carbonates (breccia/megabreccia) associated with serpulid/sphinctozoan bioconstructions
and automicrite (planar stromatolites/thrombolitic boundstone).
The whole carbonate body is completely dolomitized; nevertheless the morphology and microarchitecture of carbonate components
(cements, grains and automicrite) is still clearly recognizable. The dolomite Mg content ranges from 40 to 48 mole%, sometimes
reaching the stoichiometric value.
Cements, primary and late, represent a minor component of the rock volume; they occur more frequently on the margin and upper
slope setting. Quantitative tacies analyses lead to the following conclusions:
The sedimentary facies and the low-diversity fossil associations seem to indicate a stressed marine environment; the platform
margin probably flanked an intra-platform basin, not an open marine basin. 相似文献
– | ⊙ the entire platform is largely led by automicrite (50% in the inner platform, 70% in the margin, and 30% in the slope), with planar to columnar stromatolitic or thrombolitic fabrics; |
– | ⊙ primary skeletal framework is usually missing, although small bioconstructions of sphinctozoans and, subordinately, serpulids, occur on the slope; |
– | ⊙ automicrite has been affected by early cementation, as witnessed by non-gravitative microfabric, early fracturing and boring. |
107.
108.
Francini G Scardino A Kosmatopoulos K Lemonnier FA Campoccia G Sabatino M Pozzessere D Petrioli R Lozzi L Neri P Fanetti G Cusi MG Correale P 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(9):4840-4849
Parathyroid hormone-related protein (PTH-rP), a protein produced by prostate carcinoma and other epithelial cancers, is a key agent in the development of bone metastases. We investigated whether the protein follows the self-tolerance paradigm or can be used as a target Ag for anticancer immunotherapy by investigating the immunogenicity of two HLA-A(*)02.01-binding PTH-rP-derived peptides (PTR-2 and -4) with different affinity qualities. PTH-rP peptide-specific CTL lines were generated from the PBMC of two HLA-A(*)02.01(+) healthy individuals, stimulated in vitro with PTH-rP peptide-loaded autologous dendritic cells and IL-2. The peptide-specific CTLs were able to kill PTH-rP(+)HLA-A(*)02.01(+) breast and prostate carcinoma cell lines. The two peptides were also able to elicit a strong antitumor PTH-rP-specific CTL response in HLA-A(*)02.01 (HHD) transgenic mice. The vaccinated mice did not show any sign of side effects due to cell-mediated autoimmunity or toxicity. In this study we describe two immunogenic and toxic-free PTH-rP peptides as valid candidates for the design of peptide-based vaccination strategies against prostate cancer and bone metastases from the most common epithelial malignancies. 相似文献
109.
Emilia Bramanti Edoardo Benedetti Claudio Nicolini Tatiana Berzina Victor Erokhin Aldo D'Alessio Enzo Benedetti 《Biopolymers》1997,42(2):227-237
A qualitative and quantitative analysis of the conformation of Langmuir-Blodgett (LB) dried films of cytochrome C on silicon wafers was performed by Fourier transform ir (FTIR) spectroscopy. A deconvolution procedure was applied to the amide I band analysis, in order to determine the percentage of the different secondary structures. Qualitative analysis was performed by examining difference spectra. Films obtained by spreading protein solutions at pH 7.4 and 1, dried at 25 and 100°C, on silicon wafers were also examined in order to detect spectral components associated with denatured protein domains, and to compare them with cytochrome C LB films. FTIR spectroscopy showed that the following important changes characterise LB film spectra: (a) the α-helix component is higher (its percentage is 57 and 54%) than the one estimated in dried film obtained by spreading the solutions at pH 7.4 on a silicon substrate (43%), (b) there is an increase in the intensity of bands attributed to protonated carboxy group bands, involved and not involved in the formation of hydrogen bonds, and a decrease in those attributed to deprotonated carboxy groups, (c) the intensity of several bands attributed to aromatic amino acids and aliphatic chains increases, and (d) bands due to O(SINGLEBOND)H stretching vibrations of crystallization water are present. These conformational changes could be induced by protein-protein interaction caused by the close packing of molecules that occurs during LB film formation; it cannot be excluded that they may be accompanied by partial changes in the tertiary structure of the protein. A preferential orientation of protein molecules in LB films is also a possibility. © 1997 John Wiley & Sons, Inc. Biopoly 42: 227–237, 1997 相似文献
110.
Emilia Bramanti Edoardo Benedetti Andrea Sagripanti Federico Papineschi Enzo Benedetti 《Biopolymers》1997,41(5):545-553
The secondary structure of human fibrin from normal donors and from bovine and suilline plasma was studied by Fourier transform ir spectroscopy and a quantitative analysis of its secondary structure was suggested. For this purpose, a previously experimented spectrum deconvolution procedure based on the use of the Conjugate Gradient Minimisation Algorithm with the addition of suitable constraints was applied to the analysis of conformation-sensitive amide bands. This procedure was applied to amide I and III analysis of bovine and suilline fibrin, obtained industrially, and to amide III analysis of human fibrin clots. The analysis of both amide I and III in the first case was useful in order to test the reliability of the method. We found bovine, suilline, and human fibrin to contain about 30% α-helix (amide I and III components at 1653 cm−1, and 1312 and 1284 cm−1, respectively), 40% β-sheets (amide I and III components at 1625 and 1231 cm−1, respectively) and 30% turns (amide I and III components at 1696, 1680, 1675 cm−1, and 1249 cm−1, respectively). The precision of the quantitative determination depends on the amount of these structures in the protein. Particularly, the coefficient of variation is < 10% for percentage values of amide I and III components > 15 and 5%, respectively. The good agreement of our quantitative data, obtained separately by amide I and amide III analysis, and consistent with a previous fibrinogen (from commercial sources) study that reports only information about fibrin β-sheet content obtained by factor analysis, leads us to believe that the amounts of secondary structures found (α-helix, β-sheets, and turns) are accurate. © 1997 John Wiley & Sons, Inc. Biopoly 41: 545–553, 1997. 相似文献