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51.
Cruz HJ Conradt HS Dunker R Peixoto CM Cunha AE Thomaz M Burger C Dias EM Clemente J Moreira JL Rieke E Carrondo MJ 《Journal of biotechnology》2002,96(2):169-183
The production, purification and stability of quality (in terms of integrity and glycosylation) of an antibody/interleukin-2 fusion protein with potential application in tumour-targeted therapy expressed in BHK21 cells are described. Consistency of the product throughout time was determined by analysis of glycosylation of the fusion protein using MALDI-TOF mass spectroscopy and HPAEC-PAD combined with product integrity studies by SDS-PAGE and Western blotting. These investigations showed consistent expression in terms of integrity and of three major oligosaccharide structures of the fusion protein after 62 generations. The data obtained at this stage indicated the suitability of the cell line for production purposes. Different approaches for the production of this protein were subsequently carried out. The relative productivity of the recombinant fusion protein and general performance of the cells in two different protein-free medium (PFM) culture systems, continuous chemostat and continuous perfusion using a Centritech centrifuge as a cell retention device, were studied. The results indicate that the chemostat culture resulted in more stable and controllable nutrient environment, which could indicate better product consistency, in accordance with what has been observed under serum-containing conditions, in relation to the perfusion culture. Finally, product obtained from the chemostat culture was analysed and purified. The purification process was optimised with an increase in the overall yield from 38 to 70% being obtained, a significant improvement with important consequences for the implementation of an industrial-scale culture system. In conclusion, it was possible to produce and purify the recombinant antibody/interleukin-2 fusion protein assuring the quality and stability of the product in terms of integrity and glycosylation. Therefore, a candidate production process was established. 相似文献
52.
Neglia G Gasparrini B Di Palo R De Rosa C Zicarelli L Campanile G 《Theriogenology》2003,60(1):125-133
The aim in this study was to compare two estrus synchronization protocols in buffaloes. Animals were divided into two groups: Group A (n=111) received 100 microg GnRH on Day 0, 375 microg PGF(2alpha) on Day 7 and 100 microg GnRH on Day 9 (Ovsynch); Group B (n=117) received an intravaginal drug release device (PRID) containing 1.55 g progesterone and a capsule with 10mg estradiol benzoate for 10 days and were treated with a luteolytic dose of PGF(2alpha) and 1000 IU PMSG at the time of PRID withdrawal. Animals were inseminated twice 18 and 42 h after the second injection of GnRH (Group A) and 60 and 84 h after PGF(2alpha) and PMSG injections (Group B). Progesterone (P(4)) concentrations in milk samples collected 12 and 2 days before treatments were used to determine cyclic and non-cyclic buffaloes, and milk P(4) concentrations 10 days after Artificial insemination (AI) were used as an index of a functional corpus luteum. Cows were palpated per rectum at 40 and 90 days after AI to determine pregnancies. All previously non-cyclic animals in Group B had elevated P(4) (>120 pg/ml milk whey) on Day 10 after AI. Accordingly, a greater (P<0.01) relative percentage of animals with elevated P(4) 10 days after AI were observed in Group B (93.2%) than in Group A (81.1%). However, there was no difference in overall pregnancy rates between the two estrus synchronization protocols (Group A, 36.0%; Group B 28.2%). When only animals with elevated P(4) on Day 10 after AI were considered, pregnancy rate was higher (P<0.05) for animals in Group A (44.4%) than Group B (30.3%). The findings indicated that treatment with PRID can induce ovulation in non-cyclic buffalo cows. However, synchronization of estrus with Ovsynch resulted in a higher pregnancy rate compared with synchronization with PRID, particularly in cyclic buffalo. 相似文献
53.
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55.
Silvestre MD Lagarda MJ Farré R Martínez-Costa C Brines J Molina A Clemente G 《Biological trace element research》2000,76(3):217-227
The aim of this study was to establish the possible effects of the sampling protocol (between-breast, within-feed, and diurnal
differences) and the mother’s personal factors (age, parity, iron supple-mentation, smoking habits, and lactation period)
on the copper, iron, and zinc contents in human milk.
One hundred thirty-six human milk samples identified by their origin and sampling conditions were analyzed. The samples were
obtained from the 2nd to 15th d postpartum from 62 women. The data on the individuals required for the study were available.
Mineral determinations were analyzed by flame atomic absorption spectrometry following a standarized protocol.
The results showed that iron contents were higher in hind-milk samples and at the nighttime feeding and depended on the breast
from which the sample was taken. The copper and zinc concentrations showed no significant variations. There was no significant
relationship among the mothers’ age, parity, smoking habits, iron supplementation, and copper content. Milk from older women
had lower zinc contents than that of younger women. Increased amounts of iron were found in multiparous women. Between colostrum
and transitional milk, a sharp decrease in zinc content was observed, whereas copper and iron contents remained constant.
All of these results make it clear that standardized sampling protocols are needed in order to obtain comparable values. 相似文献
56.
Guillem A Alegría A Barberá R Farré R Lagarda MJ Clemente G 《Biological trace element research》2000,75(1-3):11-19
Seven zinc salts—acetate, chloride, lactate, sulfate, citrate, gluconate, and oxide—were added to milk—and soy-based infant
formulas to estimate possible differences in zinc availability depending on the type of salt used. For this purpose, an in
vitro method that estimates the dialyzability of the element (i.e., the fraction available for absorption) was applied. Zinc
dialyzability is always higher in milk-based products than in soy products, even when the total zinc contents are higher in
the latter.
The salts can be classified according to the zinc dialyzability in the two types of formulas as follows: oxide>gluconate=chloride=lactate>citrate=acetate>sulfate.
Therefore, according to the dialysis percentage, oxide and gluconate are the compounds of choice for zinc supplementation
of infant formulas. 相似文献
57.
Phylogenetic utility of the nuclear gene arginine decarboxylase: an example from Brassicaceae 总被引:10,自引:2,他引:8
Arginine decarboxylase (ADC) is an important enzyme in the production of
putrescine and polyamines in plants. It is encoded by a single or low-copy
nuclear gene that lacks introns in sequences studied to date. The rate of
Adc amino acid sequence evolution is similar to that of ndhF for the
angiosperm family studied. Highly conserved regions provide several target
sites for PCR priming and sequencing and aid in nucleotide and amino acid
sequence alignment across a range of taxonomic levels, while a variable
region provides an increased number of potentially informative characters
relative to ndhF for the taxa surveyed. The utility of the Adc gene in
plant molecular systematic studies is demonstrated by analysis of its
partial nucleotide sequences obtained from 13 representatives of
Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order
Capparales) and 1 from the related order Malvales. Two copies of the Adc
gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied
to data except the basal genus Aethionema. The resulting Adc gene tree
provides robust phylogenetic data regarding relationships within the
complex mustard family, as well as independent support for proposed tribal
realignments based on other molecular data sets such as those from
chloroplast DNA.
相似文献
58.
Jose Manuel Trujillo Gómez Laura Díaz-Gete Carlos Martín-Cantera Mireia Fábregas Escurriola Maribel Lozano Moreno Raquel Burón Leandro Ana María Gomez Quintero Jose Luis Ballve María Lourdes Clemente Jiménez Elisa Puigdomènech Puig Ramón Casas More Beatriz Garcia Rueda Marc Casajuana Marga Méndez-Aguirre David Garcia Bonias Soraya Fernández Maestre Jessica Sánchez Fondevila 《PloS one》2015,10(9)
59.
Alternative food sources of native and non-native bivalves in a subtropical eutrophic lake 总被引:1,自引:0,他引:1
Soledad Marroni Carlos Iglesias Néstor Mazzeo Juan Clemente Franco Teixeira de Mello Juan P. Pacheco 《Hydrobiologia》2014,735(1):263-276
The aim of this study was to evaluate the consumption of alternative food sources (water column and sediment) and the potential competition under different conditions between Diplodon parallelopipedon (native) and Corbicula fluminea (non-native). We evaluated filtration and ingestion rates of water column at 6 and 24 h, held with and without organic matter and different phytoplankton types: needle-shaped green algae (Ankistrodesmus sp.) and filamentous cyanobacteria (Planktothrix agardhii) dominated communities. Our results confirmed higher filtration and ingestion rates per biomass unit for C. fluminea in the presence of sediment without organic matter. However, when we compared the filtration of bivalves held in sediment with organic matter, D. parallelopipedon rates were not significantly different from C. fluminea values. Moreover, in the presence of filamentous cyanobacteria, only C. fluminea filtration and ingestion rates decreased significantly. Our experimental results and previous field evidence concur that C. fluminea were not able to outcompete the native bivalves in organic matter rich sediment and cyanobacteria blooms conditions. The differential responses to the eutrophication process between exotic and native bivalves, apparently favoring the later, might buffer the potential competition interactions allowing their coexistence. 相似文献
60.