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101.
102.
Epilepsy, one of the most frequent neurological disorders, is still insufficiently treated in about 30% of patients. As a consequence, identification of novel anticonvulsant agents is an important issue in medicinal chemistry. In the present article we report synthesis, physicochemical, and pharmacological evaluation of N‐trans‐cinnamoyl derivatives of R and S‐2‐aminopropan‐1‐ol, as well as R and S‐2‐aminobutan‐1‐ol. The structures were confirmed by spectroscopy and for derivatives of 2‐aminopropan‐1‐ols the configuration was evaluated by means of crystallography. The investigated compounds were tested in rodent models of seizures: maximal electroshock (MES) and subcutaneous pentetrazol test (scPTZ), and also in a rodent model of epileptogenesis: pilocarpine‐induced status prevention. Additionally, derivatives of 2‐aminopropan‐1‐ols were tested in benzodiazepine‐resistant electrographic status epilepticus rat model as well as in vitro for inhibition of isoenzymes of cytochrome P450. All of the tested compounds showed promising anticonvulsant activity in MES. For R(–)‐(2E)‐N‐(1‐hydroxypropan‐2‐yl)‐3‐phenylprop‐2‐enamide pharmacological parameters were found as follows: ED50 = 76.7 (68.2–81.3) mg/kg (MES, mice i.p., time = 0.5 h), ED50 = 127.2 (102.1–157.9) mg/kg (scPTZ, mice i.p., time = 0.25 h), TD50 = 208.3 (151.4–230.6) mg/kg (rotarod, mice i.p., time = 0.25 h). Evaluation in pilocarpine status prevention proved that all of the reported compounds reduced spontaneous seizure activity and act as antiepileptogenic agents. Both enantiomers of 2‐aminopropan‐1‐ols did not influence cytochrome P450 isoenzymes activity in vitro and are likely not to interact with CYP substrates in vivo. Chirality 28:482–488, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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Background: There is paucity of information on mechanisms constituting adverse birth outcomes. We assessed here the relationship between vascular integrity and adverse birth effects.

Methods and results: Third trimester maternal plasma (n?=?144) from the Maternal-Infant Research on Environmental Chemicals Study (MIREC) was analysed for vascular, inflammatory and oxidative stress markers by HPLC-fluorescence, protein array and EIA method. Analysis of the <25th and >75th percentile birth weight subgroups revealed markers associated with birth weight (ETs, MMP-9, VEGF, and 8-isoPGF-2α) and gestational age (ET-1, MMP-2, and VEGF).

Conclusions: Mechanistic insights into adverse birth outcome pathways can be achieved by integrating information on multiple biomarkers, physiology using systems biology approach.  相似文献   
105.
Willow herb tea or preparation are available and relatively popular in the European market, and claimed to be effective inter alia because of their anti-inflammatory activity. The present study is therefore aimed at comparing the anti-inflammatory and antioxidant activity of extracts of the three most popular Epilobium species (E. angustifolium, E. hirsutum and E. parviflorum) and at juxtaposing this activity against the dominating compounds from the following extracts: oenothein B (OeB), quercetin-3-O-glucuronide and myricetin-3-O-rhamnoside. The phytochemical analysis of the extracts has shown that OeB quantities vary between 20% and 35%, while flavonoids content does not exceed 2%. All extracts have inhibited the activity of hyaluronidase and lipoxygenase with IC50 around 5 μg/ml and 25 μg/ml. The inhibition of hyaluronidase is related with the presence of OeB, a strong inhibitor of this enzyme (IC50 1.1 μM). Additionally, the extracts inhibited myeloperoxidase (MPO) release from stimulated neutrophils. OeB inhibited MPO release similarly to the anti-inflammatory drug indomethacin with IC50 7.7 μM and 15.4 μM, respectively. Tested extracts significantly reduced the production of reactive oxygen species (ROS) from f-MLP and PMA induced neutrophils with IC50 5 μg/ml and 25 μg/ml, respectively. The flavonoids content seems to exert little influence on extracts’ activity, contrary to OeB, whose high concentration explains the activity of extract obtained from Epilobium. Tested currently marketed Epilobium preparations are often wrongly assigned, but we should stress that the level of OeB in all tested herbs was high and always exceeded 2% in raw material.  相似文献   
106.
Listeria monocytogenes strains isolated from clinical food and environmental samples were genotyped by Restriction Enzyme Analysis with Pulsed Field Gel Electrophoresis (REA-PFGE) using ApaI and AscI enzymes according to PulseNet Europe procedure. Analysis of DNA fragments profiles obtained by AscI digestion demonstrated presence of 62 REA-PFGE profiles grouped in 2 lineages (FI, FII). Diversity of strains source among both lineages was observed. Statistical analysis showed, that strains isolated from clinical samples more frequently are included to lineage FI, then lineage FII. Non-clinical strains were more frequently included to lineage FII. Combined analysis of REA-PFGE profiles for ApaI and AscI enzymes showed 8 unique pulsotypes characteristic for two or more L. monocytogenes isolates. Moreover researched L. monocytogenes strains were analyzed by multiplex-PCR according Doumith et al methodology. PCR-group 4B was most frequent among strains isolated from clinical samples. Correlation between PCR-group and pulsotype was observed only in few cases.  相似文献   
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Fascin is the main actin filament bundling protein in filopodia. Because of the important role filopodia play in cell migration, fascin is emerging as a major target for cancer drug discovery. However, an understanding of the mechanism of bundle formation by fascin is critically lacking. Fascin consists of four β-trefoil domains. Here, we show that fascin contains two major actin-binding sites, coinciding with regions of high sequence conservation in β-trefoil domains 1 and 3. The site in β-trefoil-1 is located near the binding site of the fascin inhibitor macroketone and comprises residue Ser-39, whose phosphorylation by protein kinase C down-regulates actin bundling and formation of filopodia. The site in β-trefoil-3 is related by pseudo-2-fold symmetry to that in β-trefoil-1. The two sites are ~5 nm apart, resulting in a distance between actin filaments in the bundle of ~8.1 nm. Residue mutations in both sites disrupt bundle formation in vitro as assessed by co-sedimentation with actin and electron microscopy and severely impair formation of filopodia in cells as determined by rescue experiments in fascin-depleted cells. Mutations of other areas of the fascin surface also affect actin bundling and formation of filopodia albeit to a lesser extent, suggesting that, in addition to the two major actin-binding sites, fascin makes secondary contacts with other filaments in the bundle. In a high resolution crystal structure of fascin, molecules of glycerol and polyethylene glycol are bound in pockets located within the two major actin-binding sites. These molecules could guide the rational design of new anticancer fascin inhibitors.  相似文献   
109.

Background

Type 2 diabetes is frequently associated with co-morbidities, including hypertension. Here we investigated if hypertension is a critical factor in myocardial remodeling and the development of cardiac dysfunction in type 2 diabetic db/db mice.

Methods

Thereto, 14-wks-old male db/db mice and non-diabetic db/+ mice received vehicle or angiotensin II (AngII) for 4 wks to induce mild hypertension (n = 9–10 per group). Left ventricular (LV) function was assessed by serial echocardiography and during a dobutamine stress test. LV tissue was subjected to molecular and (immuno)histochemical analysis to assess effects on hypertrophy, fibrosis and inflammation.

Results

Vehicle-treated diabetic mice neither displayed marked myocardial structural remodeling nor cardiac dysfunction. AngII-treatment did not affect body weight and fasting glucose levels, and induced a comparable increase in blood pressure in diabetic and control mice. Nonetheless, AngII-induced LV hypertrophy was significantly more pronounced in diabetic than in control mice as assessed by LV mass (increase +51% and +34%, respectively, p<0.01) and cardiomyocyte size (+53% and +31%, p<0.001). This was associated with enhanced LV mRNA expression of markers of hypertrophy and fibrosis and reduced activation of AMP-activated protein kinase (AMPK), while accumulation of Advanced Glycation End products (AGEs) and the expression levels of markers of inflammation were not altered. Moreover, AngII-treatment reduced LV fractional shortening and contractility in diabetic mice, but not in control mice.

Conclusions

Collectively, the present findings indicate that type 2 diabetes in its early stage is not yet associated with adverse cardiac structural changes, but already renders the heart more susceptible to hypertension-induced hypertrophic remodeling.  相似文献   
110.
The paper investigates seed coat characteristics (as a percentage of overall seed diameter) in Lupinus angustifolius L., a potential forage crop. In the study ten L. angustifolius genotypes, including three Polish cultivars, two Australian cultivars, three mutants originated from cv. ‘Emir’, and one Belarusian and one Australian breeding line were evaluated. The highest seed coat percentage was recorded in cultivars ‘Sonet’ and ‘Emir’. The lowest seed coat thickness percentage (below 20%) was noted for breeding lines 11257-19, LAG24 and cultivar ‘Zeus’ (17.87%, 18.91% 19.60%, respectively). Despite having low seed weight, the Australian line no. 11257-19 was characterized by a desirable proportion of seed coat to the weight of seeds. In general, estimation of the correlation coefficient indicated a tendency that larger seeds had thinner coats. Scanning Electron Microscopy images showed low variation of seed coat sculpture and the top of seeds covered with a cuticle. Most of the studied genotypes were characterized by a cristatepapillate seed coat surface, formed by elongated polygonal cells. Only breeding line no. 11267-19 had a different shape of the cells building the surface layer of the coat. In order to illustrate genetic diversity among the genotypes tested, 24 ISSR primers were used. They generated a total of 161 polymorphic amplification products in 10 evaluated narrow-leaved lupin genotypes.  相似文献   
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