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121.
Teresa Warchoł Margarita Lianeri Jan K. Łącki Paweł P. Jagodziński 《Molecular biology reports》2010,37(7):3121-3125
It has been reported that stromal cell-derived factor-1 (SDF1), currently also designated CXCL12, plays a significant role
in the development of nephritis and death in the lupus mice model. Using restriction length fragment polymorphism (RFLP) analysis
we assessed the frequencies of SDF1-3′ G801A (rs 1801157) polymorphic variants between systemic lupus erythematosus (SLE) patients (n = 150) and controls (n = 300). There were no significant differences in the prevalence of SDF1-3′ G801A polymorphic variants in SLE patients and healthy individuals. However, we observed that the SDF1-3′ A/A and G/A genotypes (recessive model) contributed to renal manifestations of SLE OR = 3.042 (95% CI = 1.527–6.058, P = 0.002), and the p value stayed statistically significant after Bonferroni correction (p
corr = 0.032) in SLE patients. We also found an association of the SDF1-3′ A/A and G/A genotypes (recessive model) with dermal manifestations of SLE OR = 2.510 (95% CI = 1.247–5.052, P = 0.0122), (p
corr = 0.1952) but this did not remain statistically significant after Bonferroni correction. Our observations suggest that the
SDF1-3′ G801A genotype may be associated with some clinical manifestations in patients with SLE. 相似文献
122.
The macrophyte vegetation of 51 ponds situated in the Duero river basin on the Northern Iberian Plateau was studied with the aim of selecting metrics that responded clearly to perturbation and that should be included in a multimetric index for assessing the ecological condition (expression of the quality of the structure and functioning of aquatic ecosystems associated with surface waters) of Mediterranean ponds. Furthermore, the specific response of metrics to the total phosphorus (TP) concentration was also investigated because of agricultural activities, which usually increase the concentration of nutrients in aquatic systems, are one of the principal types of impairment affecting ponds in the Duero basin.A total of 19 metrics representing several aspects of the structure of macrophyte communities (cover, richness, diversity) were selected as potential metrics.The strong overlap which was observed for macrophyte metrics between classes of ecological conditions (bad, poor, moderate, good, best available) and TP concentrations (>600, 600-300, 300-100, 100-50, <50 μg L−1 TP) constitutes a major problem in defining and separating these classes. For this reason, Mann-Whitney U-test and discrimination efficiency were carried out to determine which of the measures best discriminated between slightly impaired sites (ponds in good or best available condition) and perturbed ponds (ponds in moderate, poor or bad condition). Most of the metrics showed significant differences (p < 0.05) between slightly impaired and perturbed ponds. However, only total cover and hydrophyte richness, which had the highest discrimination efficiency (>78%), showed no inter-quartile overlap (25th-75th percentile) between the two ecological classes. For these reasons, both total cover and hydrophyte richness were selected for the implementation of a multimetric index able to discriminate between slightly impaired and degraded Mediterranean flatland ponds.Currently, eutrophication is considered the main pressure on lakes. However, macrophyte metrics were far less sensitive to TP concentration than to ecological condition changes. This shows that other pressures are also of considerable importance. Thus, the definition of the ecological condition of lakes using macrophytes should not be based only on responses to eutrophication pressure, as has been done in some European countries. 相似文献
123.
Andrea Kopp Margarita Bala Johanna Weigert Christa Büchler Markus Neumeier Charalampos Aslanidis Jürgen Schölmerich Andreas Schäffler 《Cytokine》2010,49(1):51-57
Aims/Hypothesis: It was the aim to investigate the hypothesis that the new C1q/TNF-family member CTRP-3 (C1q/TNF-related protein-3) acts anti-inflammatory in human monocytes from healthy controls and patients with type 2 diabetes mellitus (T2D). Methods: Monocytes were isolated from 20 healthy controls and 30 patients with T2D. IL-6 and TNF concentrations were measured by ELISA. CTRP-3 was expressed in insect cells and used for stimulation experiments. Results: Basal IL-6 and TNF were not different in control and in T2D monocytes. LPS-stimulation (1 μg/ml) significantly (p < 0.001) increased IL-6 and TNF in the supernatants of control and in T2D monocytes to a similar extent. CTRP-3 (1 μg/ml) significantly (p = 0.03) inhibited LPS-induced IL-6 in control monocytes but not in T2D monocytes. TNF upon co-stimulation with LPS and CTRP-3 was significantly (p = 0.012) lower in control than in T2D monocytes. LPS-induced TNF concentration was significantly and positively correlated with serum total cholesterol and LDL cholesterol in T2D patients. Conclusions: CTRP-3 inhibits LPS-induced IL-6 and TNF release. This anti-inflammatory effect is lost in T2D. Serum cholesterol concentration affects the pro-inflammatory potential of LPS to induce TNF release from T2D monocytes in the presence or absence of CTRP-3. CTRP-3 might partly account for the pro-inflammatory state in T2D. 相似文献
124.
Mario Arias Zabala Mónica Angarita Juan M. Restrepo Luis A. Caicedo Margarita Perea 《In vitro cellular & developmental biology. Plant》2010,46(3):233-238
Thevetia peruviana is a small tree that produces several compounds with pharmaceutical application, among which peruvoside could be highlighted.
However, these compounds are produced in low concentration in the plant, making it important to develop strategies such as
plant cell culture and elicitation to obtain higher quantities of the desired product. In this work, cell suspension cultures
of T. peruviana were established in four different culture media: Murashige–Skoog (MS), half Murashige–Skoog (half MS), Schenk–Hildebrandt
(SH), and Gamborg (B5) to study their effect on cell growth. Cell growth kinetics were studied in SH medium, and the extracellular
peruvoside production during the culture time was determined. The best culture medium for the establishment of cell suspension
cultures was MS with a growth index of 3.17 ± 0.2 g g−1 inoculum. The cell growth kinetics showed the four characteristic growth phases of a cell culture (lag, exponential, stationary,
and death), and during none of these phases was it possible to observe peruvoside production. The elicitor effect of methyl-jasmonate
(MeJ) was studied in cell suspension cultures established in SH medium. The effect of MeJ concentration and the time in which
it should be applied were determined. The best results were obtained at a concentration of 100 mg l−1 of MeJ applied at the beginning of the culture, which induced a peruvoside production of 8.93 mg l−1 medium. The current results are the first report of an in vitro peruvoside production system. 相似文献
125.
Hortensia Rodríguez Margarita Suarez Fernando Albericio 《Journal of peptide science》2010,16(3):136-140
Structural modification of the peptide backbone via N‐methylation is a powerful tool to modulate the pharmacokinetic profile and biological activity of peptides. Here we describe a rapid and highly efficient microwave(MW)‐assisted Fmoc/tBu solid‐phase method to prepare short chain N‐methyl‐rich peptides, using Rink amide p‐methylbenzhydrylamine (MBHA) resin as solid‐phase support. This method produces peptides in high yield and purity, and reduces the time required for Fmoc‐N‐methyl amino acid coupling. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
126.
Jorge Sastre-Serra Adamo Valle Maria Margarita Company Isabel Garau Jordi Oliver Pilar Roca 《Free radical biology & medicine》2010,48(4):506-512
Oxidative stress has been postulated as one of the mechanisms underlying the estrogen carcinogenic effect in breast cancer. Estrogens are known to increase mitochondrial-derived reactive oxygen species (ROS) by an unknown mechanism. Given that uncoupling proteins (UCPs) are key regulators of mitochondrial energy efficiency and ROS production, our aim was to check the presence and activity of UCPs in estrogen receptor (ER)-positive and ER-negative breast cancer cells and tumors, as well as their relation to oxidative stress. Estrogen (1 nM) induced higher oxidative stress in the ER-positive MCF-7 cell line, showing increased mitochondrial membrane potential, H2O2 levels, and DNA and protein damage compared to ER-negative MDA-MB-231 cells. All isoforms of uncoupling proteins were highly expressed in ER-positive breast cancer cells and tumors compared to negative ones. ROS production in mitochondria isolated from MCF-7 was increased by inhibition of UCPs with GDP, but not in mitochondria from MDA-MB-231. Estrogen treatment decreased uncoupling protein and catalase levels in MCF-7 and decreased GDP-dependent ROS production in isolated mitochondria. On the whole, these results suggest that estrogens, through an ER-dependent mechanism, may increase mitochondrial ROS production by repressing uncoupling proteins, which offers a new perspective on the understanding of why estrogens are a risk factor for breast cancer. 相似文献
127.
Yuri N. Belokon Victor I. Maleev Tatiana F. Savel’eva Margarita A. Moskalenko Dmitri A. Pripadchev Victor N. Khrustalev Ashot S. Saghiyan 《Amino acids》2010,39(5):1171-1176
A novel simple synthetic protocol for the preparation of both (2S,4R)- and (2S,4S)-FGlu, applying Michael addition of methyl α-fluoroacrylate to a NiII complex of glycine Schiff base with BPB, was elaborated. In addition, same reaction of mentioned complex with ethyl α-bromoacrylate leads to the NiII complex of the Schiff base of BPB with (2S,4R)-4-bromo-glutamic acid monoester, that can be transformed into the corresponding complexes of 1-aminocyclopropane-1,2-dicarboxylic
acid. The decomposition of the diastereoisomerically pure complexes leads to corresponding enantiomerically enriched (ee > 98%) amino acids. 相似文献
128.
In this study we present an optimized method of high-pressure freezing and automated freeze-substitution of cultured human
cells, followed by LR White embedding, for subsequent immunolabeling. Also, the influence of various conditions of the freeze-substitution
procedures such as temperature, duration, and additives in the substitution medium on the preservation of cryo-immobilized
cells was analyzed. The recommended approach combines (1) automated freeze-substitution for high reproducibility and minimizing
human-derived errors; (2) minimal addition of contrasting and fixing agents; (3) easy-to-use LR White resin for embedment;
(4) good preservation of nuclei and nucleoli which are usually the most difficult structures to effectively vitrify and saturate
in a resin; and (5) preservation of antigens for sensitive immunogold labeling. 相似文献
129.
Crespo R de Bravo MG Colinas PA Bravo RD 《Bioorganic & medicinal chemistry letters》2010,20(22):6469-6471
A series of α-D-hex-2-enopyranosyl sulfonamides was evaluated for their antiproliferative activity against human hepatocellular liver carcinoma (HepG2) and human lung adenocarcinoma (A549) cell lines. The most potent compound (2,4,6-tri-O-acetyl-3-deoxy-α-D-erythro-hex-2-enopyranosyl ethanesulfonamide) showed antiproliferative properties in the micromolar range. The SARs of these sulfonamidoglycoside which includes the influence of carbohydrate rings and sulfonamide class are described. 相似文献
130.
Teresa Mancilla-Percino José Correa-Basurto José Trujillo-Ferrara Fernando R. Ramos-Morales Mario E. Acosta Hernández Jesús S. Cruz-Sánchez Margarita Saavedra-Vélez 《Journal of molecular modeling》2010,16(8):1377-1382
Two series of isoindolines 1(a–g) and 2(a–g) were found by docking calculations to be possible L-type Ca2+ channel (LCC) blockers. The theoretical 3-D model of the outer vestibule and the selective filter of the LCC was provided
by Professor Lipkind; this model consists of transmembrane segments S5 and S6 and P-loops contributed by each of four repeats
(I, II, III, and IV) of Cav 1.2. Therefore, two well-known LCC blockers, nifedipine 3 and (R)-ethosuccinimide 4 were also evaluated, and their binding sites on the LCC were identified and compared with those obtained for 1(a–g) and 2(a–g). Analysis of the results shows that the target compounds tested probably could be LCC blockers, since they interact with
or near the glutamic acid residues Glu393, Glu736, Glu1145 and Glu1446 (the EEEE locus), which belong to the LCC selectivity
region. The ∆G values for all of the Ca2+ channel ligands are between−10.78 and −3.67 (kcal mol−1), showing that LCC-1b, -1e and -1f complexes are more stable than the other compounds tested. Therefore, theoretically calculated dissociation constants K
d (μM) were obtained for all compounds. Comparing these values reveals that compounds 1b (0.0244 μM), 1e (0.0176 μM) and 1f (0.0125 μM) exhibit more affinity for the LCC than the other compounds. This screening shows that the two series of isoindolines
probably could act as LCC blockers. 相似文献