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441.
I Salom S Román G Macaya J Fonseca F Brenes C Mora A Martén 《Revista de biología tropical》1990,38(1):83-86
Nine different groups of individuals studied from 1969 to 1985 were tested for Hepatitis B Virus (HBV) markers. In 8 groups only HBsAg in serum was tested, in another group: tissular HBsAg, and in two of those groups: serum HBsAg, anti-HBs and anti-HBc. Mean HBsAg prevalence in groups similar to general population was 0.64%; 5% in cirrhotics; HBV prevalence in haemophiliacs was 18.87% by testing serum for HBsAg and anti-HBs; serum HBsAg prevalence in Viral Chronic Active Hepatitis was 43.24%; and Hepatocellular Cancer (HCC) group had a prevalence for HBV of 13.04% when only tissular HBsAg was tested, and 54.29% when serum HBsAg, anti-HBs and anti-HBc were tested in all patients. Costa Rica has a low HBV markers prevalence only similar to what is found in industrial developed countries. 相似文献
442.
Emilianne Miguel Salom?o Maria Cristina Cintra Gomes-Marcondes 《Journal of physiology and biochemistry》2012,68(4):493-501
Nutritional supplementation with some amino acids may influence host??s responses and also certain mechanism involved in tumor progression. It is known that exercise influences body weight and muscle composition. Previous findings from our group have shown that leucine has beneficial effects on protein composition in cachectic rat model as the Walker 256 tumor. The main purpose of this study was to analyze the effects of light exercise and leucine and/or glutamine-rich diet in body composition and skeletal muscle protein synthesis and degradation in young tumor-bearing rats. Walker tumor-bearing rats were subjected to light aerobic exercise (swimming 30?min/day) and fed a leucine-rich (3%) and/or glutamine-rich (4%) diet for 10?days and compared to healthy young rats. The carcasses were analyzed as total water and fat body content and lean body mass. The gastrocnemious muscles were isolated and used for determination of total protein synthesis and degradation. The chemical body composition changed with tumor growth, increasing body water and reducing body fat content and total body nitrogen. After tumor growth, the muscle protein metabolism was impaired, showing that the muscle protein synthesis was also reduced and the protein degradation process was increased in the gastrocnemius muscle of exercised rats. Although short-term exercise (10?days) alone did not produce beneficial effects that would reduce tumor damage, host protein metabolism was improved when exercise was combined with a leucine-rich diet. Only total carcass nitrogen and protein were recovered by a glutamine-rich diet. Exercise, in combination with an amino acid-rich diet, in particular, leucine, had effects beyond reducing tumoral weight such as improving protein turnover and carcass nitrogen content in the tumor-bearing host. 相似文献
443.
Glutamine synthetase (EC 6.3.1.2) was purified to homogeneity from a free-living nitrogen fixing bacteria, Bacillus polymyxa. The holoenzyme, relative molecular mass (Mr) of 600 000 is composed of monomeric sub-units of 60 000 (Mr). The isoelectric point of the sub-units was 5.2. The pH optimum for the biosynthetic and transferase enzyme activity was 8.2 and 7.8, respectively. The apparent K
m values (K
m
app
) in the biosynthetic reaction for glutamate, NH4Cl and ATP were 3.2, 0.22 and 1 mM, respectively. In the transferase reaction the K
m values for glutamine, hydroxylamine and ADP were 6.5, 3.5 and 8×10-4 mM respectively. L-Methionine-D-L-sulfoximine was a very potent inhibitor in both biosynthetic and transferase reactions. Similar to most Gram positive bacteria there was no evidence of in vivo adenylylation and the enzyme seemed to be mainly regulated by feed-back mechanism.Abbreviations PMSF
phenylmethylsulfonylfluoride
- TCA
trichloroacetic acid
- GS
glutamine synthetase
- MSO
L-Methionine-D-L-sulfoximine
- SDS-PAGE
sodium dodecyl sulfatepolyacrylamide gel electrophoresis
- SVPDE
snake venum phosphodiesterase 相似文献
444.
Maria Kahlert Martyn Kelly Raino-Lars Albert Salomé F. P. Almeida Tomáš Bešta Saúl Blanco Michel Coste Luc Denys Luc Ector Markéta Fránková Daša Hlúbiková Plamen Ivanov Bryan Kennedy Petr Marvan Adrienne Mertens Juha Miettinen Joanna Picinska-Fałtynowicz Juliette Rosebery Elisabet Tornés Sirje Vilbaste Andrea Vogel 《Hydrobiologia》2012,680(1):109-124
The heterogeneity of oxygen distribution in a Hediste diversicolor burrow environment was investigated in a laboratory experiment using a 6-mm thick tank equipped with oxygen planar optodes.
The two-dimensional oxygen distribution in a complete burrow was monitored every 2 min for 4 h. Oxygen concentrations fluctuated
over a scale of minutes in the burrow lumen and wall (up to 2 mm) reflecting the balance between worm ventilation activity
and oxygen consumption. The magnitude of the three surrounding micro-horizons (oxic, oscillating and anoxic) induced by the
intermittent worm ventilation was spatially and temporally variable within the structure. Oxygen variations appeared to be
controlled by distance from the sediment–water interface and the direction of water circulation. Moreover, there was an apparent
‘buffer effect’, induced by the proximity to the overlying water, which reduced the variations of lumen and wall oxygen in
the upper part of the structure. These results highlight the heterogeneous distribution and dynamics of oxygen associated
with H. diversicolor burrows and ventilation activity. They also highlight the necessity of integrating this complexity into the current burrow-base
models in order to estimate the ecological importance of burrowing species in coastal ecosystems. 相似文献
445.
Caroline Bouchard Salomé Mollard Keita Suzuki Dominique Robert Louis Fortier 《Polar Biology》2016,39(6):1005-1022
The early life stages of Boreogadus saida and Arctogadus glacialis are morphologically similar, making it difficult to assess differences in their ecological niche. The present study documented for the first time the early life stage ecology of A. glacialis, compared it to that of B. saida, and identified the factors separating the niches of the two sympatric species. The 10,565 larval gadids collected in the Beaufort Sea from April to August of 2004 and 2008 were identified to species either directly by genetics and/or otolith nucleus size, or indirectly with a redistribution procedure. Between 8.0 and 8.7 % of all gadids were assigned to A. glacialis. Larvae of A. glacialis were longer at hatch and experienced lower mortality rates than those of B. saida. The two species shared similar spatiotemporal and vertical distributions, hatching season, and growth rate. Under the ice, feeding incidence of B. saida was low (14 %) relative to A. glacialis (88 %). At lengths <15 mm, both species specialized on different prey. The diet of fish >15 mm overlapped (Schoener’s index = 0.7), with Calanus glacialis and C. hyperboreus providing >50 % of the carbon intake of both species. The higher mortality in B. saida may be explained by the smaller size at age from hatching to metamorphosis and a lower under-ice feeding incidence. The early larval stage appears to be the key period of niche divergence between the two species. 相似文献
446.
447.
Bárbara Salomão de Faria Müller Tetsu Sakamoto Ricardo Diógenes Dias Silveira Patricia Fernanda Zambussi-Carvalho Maristela Pereira Georgios Joanis Pappas Jr Marcos Mota do Carmo Costa Cleber Moraes Guimarães Wendell Jacinto Pereira Claudio Brondani Rosana Pereira Vianello-Brondani 《Plant Molecular Biology Reporter》2014,32(2):438-451
448.
Killer immunoglobulin‐like receptor repertoire analysis in a Caucasian Spanish cohort with inflammatory bowel disease 下载免费PDF全文
Ruth López‐Hernández Jose A. Campillo Isabel Legaz Mariano Valdés Hortensia Salama Francisco Boix AM Hernández‐Martínez Jorge Eguia G González‐Martínez Maria R. Moya‐Quiles Alfredo Minguela Ana García‐Alonso Fernando Carballo Manuel Muro 《Microbiology and immunology》2016,60(11):787-792
Immunological molecules are implicated in inflammatory disorders, including inflammatory bowel disease (IBD; Crohn disease [CD] and ulcerative colitis [UC]). Killer cell immunoglobulin‐like receptors (KIRs) are also genetically variable proteins involved in immune function. They are expressed by NK cells and certain T lymphocytes, regulate specificity and function by interaction with HLA Class I molecules, may be either inhibitory or activating and are polymorphic both in terms of alleles and haplotype gene content. Genetic associations between activating KIRs and certain autoimmune and inflammatory diseases have been reported; however, a possible association between KIR and IBD remains unclear. The aim of this study was to determine the relationship between KIR repertoire and IBD pathologies in a Spanish cohort. KIR variability was analyzed using PCR–sequence specific oligonucleotide probes (SSOP). Inhibitory KIR2DL5 was found more frequently in UC and IBD patient groups than in healthy controls (P = 0.028 and P = 0.01, respectively), as was activating KIR2DS1 (P = 0.02, Pc > 0.05, UC vs. Controls; P = 0.001, Pc = 0.01, IBD vs Controls; P = 0.01, Pc > 0.05, Controls vs CR), KIR2DS5 (P = 0.0028, Pc = 0.04, Controls vs UC; P = 0.0001, Pc = 0.0017, Controls vs IBD; P = 0.01, Pc > 0.05, Controls vs CD) and KIR3DS1 (P = 0.012, Pc > 0.05, Controls vs IBD). Our data suggest that imbalance between activating and inhibitory KIR may partially explain the different pathogeneses of these IBDs and that there is a hypothetical role for the telomeric B region (which contains both KIR2DS5 and KIR2DS1) in these diseases. 相似文献
449.
Summary Frieble calli, obtained from petioles ofGeranium roberlianum were used for the production of cell suspension cultures in liquid MS modified medium supplemented with BAP and NAA. Casamino acids were shown to be necessary for suspension cultures establishment With a 15.9×104 cell. ml–1 concentration a td=38.2h was achieved. 相似文献
450.
Filomena Calixto M. Salomé Pais 《In vitro cellular & developmental biology. Plant》1997,33(2):119-124
Summary
Pinus pinaster plants were regenerated from cotyledons excised from in vitro germinated seeds and axenically cultured on induction medium (GMD). 6-Benzyladenine (2.2 μM) induced the highest frequency of direct bud formation from cotyledons. An average of 13.1 ± 2.1 elongated shoots per cotyledon
was obtained. Germination time influenced shoot induction, and the organogenic potential decreased with explant age. Cotyledons
remained for 21 d on induction medium, and in order to promote adventitious shoot elongation, they were transferred to Gupta
and Durzan’s DCR medium without growth regulators, containing 0.5% (wt/vol) activated charcoal and 3% (wt/vol) sucrose. Rooting
was achieved by application of an indole-3-butyric acid, (396.6 μM) pulse (24 h at 4° C), followed by transfer to a sterile mixture of peat plus perlite (1:1 vol/vol). Ninety-eight to 100%
of the regenerated plants were successfully acclimatized. All plants have survived after transfer to the field. 相似文献