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101.
A. E. Ruiz‐Contreras K. Carrillo‐Sánchez I. Ortega‐Mora M. A. Barrera‐Tlapa T. V. Román‐López C. B. Rosas‐Escobar L. Flores‐Barrera U. Caballero‐Sánchez Z. Muñoz‐Torres S. Romero‐Hidalgo S. Hernández‐Morales J. A. González‐Barrios F. Vadillo‐Ortega M. Méndez‐Díaz R. Aguilar‐Roblero O. Prospéro‐García 《Genes, Brain & Behavior》2014,13(2):173-178
Individual differences in cognitive performance are partly dependent, on genetic polymporhisms. One of the single‐nucleotide polymorphisms (SNP) of the CNR1 gene, which codes for cannabinoid receptor 1 (CB1R), is the rs2180619, located in a regulatory region of this gene (6q14–q15). The alleles of the rs2180619 are A > G; the G allele has been associated with addiction and high levels of anxiety (when the G allele interacts with the SS genotype of the 5‐HTTLPR gene). However, GG genotype is observed also in healthy subjects. Considering G allele as risk for ‘psychopathological conditions’, it is possible that GG healthy subjects do not be addicted or anxious, but would have reduced performance, compared to AA subjects, in attentional control and working memory processing. One hundred and sixty‐four healthy young Mexican‐Mestizo subjects (100 women and 64, men; mean age: 22.86 years, SD=2.72) participated in this study, solving a task where attentional control and working memory were required. GG subjects, compared to AA subjects showed: (1) a general lower performance in the task (P = 0.02); (2) lower performance only when a high load of information was held in working memory (P = 0.02); and (3) a higher vulnerability to distractors (P = 0.03). Our results suggest that, although the performance of GG subjects was at normal levels, a lower efficiency of the endocannabinoid system, probably due to a lowered expression of CB1R, produced a reduction in the performance of these subjects when attentional control and working memory processing is challenged . 相似文献
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104.
Juan Herrero Alicia García-Serrano Sergio Couto Vicente M. Ortuño Ricardo García-González 《European Journal of Wildlife Research》2006,52(4):245-250
The Middle Ebro Valley (MEV) is a semiarid area in northeast Iberia where the original riparian ecosystems are almost extinct
and were replaced by intensive irrigated agricultural lands. To minimize crop damages and to understand the impact of wild
boar on relict riparian ecosystems, a culling program was undertaken from 1994 until 2004. To assess the impact of wild boars,
we analyzed stomach contents and surveyed crop damage. In the MEV, wild boars feed mainly on crops, particularly, maize. Other
elements of the diet that are of agricultural origin include wheat, barley, and alfalfa, which are the alternatives to maize
in the period between harvest and seeding, which is the basis of seasonal changes in diet. Results indicate that wild boar
actively selected maize crops and consumed wheat in proportion to its abundance; barley and alfalfa fields were damaged less
than expected based on their abundance. In the MEV, the wild boar population is limited by the availability of shelter areas
found in the scarce riparian ecosystems, which do not provide important food items for this population. We conclude that in
the region of this study, wild boars are not a significant threat to the flora and fauna of riparian ecosystems, although
as these habitats are restored and areas are protected, the carrying capacity for wild boars might increase. 相似文献
105.
Mirabet V Solves P Miñana MD Encabo A Carbonell-Uberos F Blanquer A Roig R 《Cell and tissue banking》2008,9(1):1-10
Several studies have shown the presence of fibroblast-like cells in the stromal fraction of different tissues with a high
proliferative and differentiation potential. Platelet alpha granules contain growth factors released into the environment
during activation. The effects of different supplements for culture medium (human serum, bovine serum and platelet lysate)
on cultured human fibroblast-like cells from bone marrow, adipose tissue, trabecular bone and dental pulp have been compared.
Expression of typical stromal and hematopoietic markers was analyzed and proliferative rates were determined. Flow cytofluorometry
showed a homogenous pattern in serial-passaged cells, with a high level of stromal cell-associated markers (CD13, CD90, CD105).
The presence of platelet lysate in culture media increased the number of cell generations obtained regardless of cell source.
This effect was serum-dependent. Cell-based therapies can benefit by the use of products from human origin for “ex vivo” expansion
of multipotent cells. 相似文献
106.
Ortega AL Carretero J Obrador E Gambini J Asensi M Rodilla V Estrela JM 《The Journal of biological chemistry》2003,278(16):13888-13897
High GSH content associates with high metastatic activity in B16-F10 melanoma cells cultured to low density (LD B16M). GSH homeostasis was investigated in LD B16M cells that survive after adhesion to the hepatic sinusoidal endothelium (HSE). Invasive B16M (iB16M) cells were isolated using anti-Met-72 monoclonal antibodies and flow cytometry-coupled cell sorting. HSE-derived NO and H(2)O(2) caused GSH depletion and a decrease in gamma-glutamylcysteine synthetase activity in iB16M cells. Overexpression of gamma-glutamylcysteine synthetase heavy and light subunits led to a rapid recovery of cytosolic GSH, whereas mitochondrial GSH (mtGSH) further decreased during the first 18 h of culture. NO and H(2)O(2) damaged the mitochondrial system for GSH uptake (rates in iB16M were approximately 75% lower than in LD B16M cells). iB16M cells also showed a decreased activity of mitochondrial complexes II, III, and IV, less O(2) consumption, lower ATP levels, higher O(2) and H(2)O(2) production, and lower mitochondrial membrane potential. In vitro growing iB16M cells maintained high viability (>98%) and repaired HSE-induced mitochondrial damages within 48 h. However, iB16M cells with low mtGSH levels were highly susceptible to TNF-alpha-induced oxidative stress and death. Therefore depletion of mtGSH levels may represent a critical target to challenge survival of invasive cancer cells. 相似文献
107.
Jan Vicente Allison Stewart Bongkeun Song Russell T. Hill Jeffrey L. Wright 《Marine biotechnology (New York, N.Y.)》2013,15(4):413-424
Marine actinomycetes provide a rich source of structurally unique and bioactive secondary metabolites. Numerous genera of marine actinomycetes have been isolated from marine sediments as well as several sponge species. In this study, 16 different species of Caribbean sponges were collected from four different locations in the coastal waters off Puerto Rico in order to examine diversity and bioactive metabolite production of marine actinomycetes in Caribbean sponges. Sediments were also collected from each location, in order to compare actinomycete communities between these two types of samples. A total of 180 actinomycetes were isolated and identified based on 16S rRNA gene analysis. Phylogenetic analysis revealed the presence of at least 14 new phylotypes belonging to the genera Micromonospora, Verruscosispora, Streptomyces, Salinospora, Solwaraspora, Microbacterium and Cellulosimicrobium. Seventy-eight of the isolates (19 from sediments and 59 from sponges) shared 100 % sequence identity with Micromonospora sp. R1. Despite having identical 16S rRNA sequences, the bioactivity of extracts and subsequent fractions generated from the fermentation of both sponge- and sediment-derived isolates identical to Micromonospora sp. R1 varied greatly, with a marked increase in antibiotic metabolite production in those isolates derived from sponges. These results indicate that the chemical profiles of isolates with high 16S rRNA sequence homology to known strains can be diverse and dependent on the source of isolation. In addition, seven previously reported dihydroquinones produced by five different Streptomyces strains have been purified and characterized from one Streptomyces sp. strain isolated in this study from the Caribbean sponge Agelas sceptrum. 相似文献
108.
Carmen Rojas-Martínez Roger Iván Rodríguez-Vivas Julio Vicente Figueroa Millán Carlos Ramón Bautista-Garfias Roberto Omar Castañeda-Arriola José Juan Lira-Amaya Patricia Vargas Urióstegui Juan José Ojeda Carrasco Jesús Antonio Álvarez Martínez 《Parasitology international》2018,67(2):190-195
An attenuated live vaccine containing Babesia bovis and B. bigemina cultured in vitro with a serum-free medium was assessed for its clinical protection conferred of naïve cattle, under natural tick-challenge in a high endemicity zone to Babesia spp. Three groups of six animals were treated as follows: group I (GI) received a vaccine derived from parasites cultured with a free-serum medium; group II (GII) were immunized with the standard vaccine, with parasites cultured in a medium supplemented with 40% (v/v) bovine serum; and a control group (GIII) inoculated with non-infected bovine erythrocytes. Inocula were administered by IM route. Experimental animals were kept during 23 days after vaccination in a cattle farm free of ticks and Babesia spp. Thereafter, cattle were moved to a high endemicity farm for natural exposure to Babesia spp. transmitted by Rhipicephalus microplus ticks. Protection against clinical babesiosis was observed in bovines belonging to GI (100%) and GII (83.33%), while the control animals (GIII) were not protected, and showed severe clinical signs, closely related to babesiosis, were observed for at least three consecutive days during the challenge. These were fever, anemia, which were measured simultaneously, and circulating parasites were detected by optic light microscopy. All cattle showed B. bovis and B. bigemina in stained blood films during the challenge; B. bovis antibody titers were higher than those to B. bigemina in GI and GII, and lower titers were determined in GIII. The protective capacity of the vaccine derived from B. bovis and B. bigemina cultured in vitro in a serum-free medium was demonstrated. 相似文献
109.
Human fibroblasts show expression of the leukotriene-A4-hydrolase gene, which is increased after simian-virus-40 transformation 总被引:3,自引:0,他引:3
J F Medina C Barrios C D Funk O Larsson J Haeggstr?m O R?dmark 《European journal of biochemistry》1990,191(1):27-31
Human fibroblasts in cell culture converted the epoxide intermediate leukotriene A4 into the potent chemotaxin leukotriene B4. The identity of leukotriene B4 was ascertained by its mobility in reverse-phase high performance liquid chromatography, ultraviolet spectroscopy and gas chromatography/mass spectrometry. The presence of the enzyme responsible for the conversion (i.e. leukotriene A4 hydrolase), as well as the corresponding mRNA, were demonstrated by Western and Northern blot analyses. Leukotriene-A4-hydrolase enzyme activity, protein and mRNA were all enhanced (approximately threefold) in human fibroblasts that had been transformed by simian virus 40. 相似文献
110.