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1.
This review provides an evaluation of the correlates and/or risk factors associated with disordered eating and the pursuit of muscularity among adolescent boys. One of the main conclusions is that similar factors and processes are associated with both behavioral problems. Several factors found to be consistently associated with disordered eating among boys are also similar to those found with girls. These include body mass index, negative affect, self-esteem, perfectionism, drug use, perceived pressure to lose weight from parents and peers, and participation in sports that focus on leanness. However, as many of the findings have only been verified using cross-sectional designs, prospective studies are now needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disorder. There is no cure and current treatments fail to slow the progression of the disease. Epigenetic modulation in the acetylation state of NF-kB RelA and the histone 3 (H3) protein, involved in the development of neurodegeneration, is a drugable target for the class-I histone deacetylases (HDAC) inhibitors, entinostat or valproate, and the AMP-activated kinase (AMPK)-sirtuin 1 pathway activator, resveratrol. In this study, we demonstrated that the combination of valproate and resveratrol can restore the normal acetylation state of RelA in the SOD1(G93A) murine model of ALS, in order to obtain the neuroprotective form of NF-kB. We also investigated the sexually dimorphic development of the disease, as well as the sex-sensibility to the treatment administered. We showed that the combined drugs, which rescued AMPK activation, RelA and the histone 3 acetylation state, reduced the motor deficit and the disease pathology associated with motor neuron loss and microglial reactivity, Brain-Derived Neurotrophic Factor (BDNF) and B-cell lymphoma-extra large (Bcl-xL) level decline. Specifically, vehicle-administered males showed earlier onset and slower progression of the disease when compared to females. The treatment, administered at 50 days of life, postponed the time of onset in the male by 22 days, but not in a significant way in females. Nevertheless, in females, the drugs significantly reduced symptom severity of the later phase of the disease and prolonged the mice’s survival. Only minor beneficial effects were produced in the latter stage in males. Overall, this study shows a beneficial and sexually dimorphic response to valproate and resveratrol treatment in ALS mice.  相似文献   
3.
The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low.  相似文献   
4.
The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens.  相似文献   
5.
The cultivar Pacific Russet with high browning susceptibility was used for most testing. Controlled atmospheres (0.3%, 3% and 21% O2 in combination with 0%, 6% or 12% CO2) and anti‐browning chemicals were studied in relation to quality retention and wound‐induced phenolic metabolism of fresh‐cut slices for up to 16 days at 5 °C. The 3% O2+ 12% CO2 atmosphere was most effective among those tested, and retarded increases in phenolics and phenylalanine ammonia lyase activity, but had only slight benefit on visual quality. A 1.25% ascorbic acid +1.25% citric acid treatment was ineffective, but when combined with 3% O2+ 12% CO2, it was comparable with 0.025% sodium bisulphite. Bisulphite concentrations from 0.05% to 0.25% provided similar effective control of discolouration. Bisulphite as low as 0.025% with 3% O2+ 12% CO2 resulted in a visual quality score at the limit of marketability after 8 days at 5 °C. Chemical treatments did not retard increases in phenolic concentrations or phenolic enzyme activities.  相似文献   
6.
In this research acrylamide reduction in potato chips was investigated in relation to blanching and asparaginase immersion treatments before final frying. Potatoes slices (Verdi variety, diameter: 40 mm, thickness: 2.0 mm) were fried at 170 °C for 5 min (final moisture content of ∼2.0 g/100 g). Prior to frying, potato slices were treated in one of the following ways: (i) Rinsing in distilled water (control I); (ii) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min; (iii) Rinsing in distilled water plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C for 20 min; (iv) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C for 20 min; (v) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in distilled water at 50 °C for 20 min (control II). Blanching in hot water (ii) was almost as effective as asparaginase potato immersion (iii) in order to diminish acrylamide formation in potato chips (acrylamide reduction was ∼17% of the initial acrylamide concentration). When potato slices were blanched before asparaginase immersion, the acrylamide content of the resultant potato chips was reduced considerably by almost 90%. We have demonstrated that blanching of potato slices plus asparaginase treatment is an effective combination for acrylamide mitigation during frying. It seems to be that blanching provokes changes in the microstructure of potato tissue leading to an easier and more effective diffusion of asparaginase.  相似文献   
7.
    
Zusammenfassung Es wird eine Phasenumkehr-HPLC-Methode beschrieben, die es gestattet, dieAlternaria-Toxine Alternariol (AOH), Alternariolmonomethylether (AME), Altenuen (ALT) und Altertoxin I (ATX-I) in Obst- und Gemüseerzeugnissen mit guter Empfindlichkeit zu bestimmen. Die Ergebnisse werden dünnschichtchromatographisch abgesichert. Sie wurde an ca. 50 Handelsprodukten Bowie an ca. 20 verschimmelten Früchten erprobt. Keines der Handelsprodukte war mit den o. g. Mykotoxinen kontaminiert, während zwei der verschimmelten Proben (Äpfel) 160 ppb AOH, bzw. 250 ppb AME enthielten.
Determination of alternaria toxins in fruit and vegetable products
Summary A reverse phase HPLC method for the determination of theAlternaria mycotoxins alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT) and altertoxin I (ATX-I) in fruit and vegetable products is described. The procedure has good sensitivity. The results are corroborated by TLC. About 50 commercial products and about 20 mouldy fruits were analysed. None of the commercial products was contaminated with the toxins whereas two of the mouldy samples (apples) contained 160 ppb AOH respectively 250 ppb AME.
  相似文献   
8.
This paper aims to clarify current knowledge on the contribution of communication to crisis management in the case of terrorism incidents. This is done by means of a systematic review of the scientific literature on terrorism communication over the last 10 years to identify the many challenges facing communication in such crises, and represents the first attempt of its kind. To date, within the literature on terrorism communication, much attention has been paid to chemical, biological, radiological or nuclear hazards. Terrorism crises are complex and challenging. Preparedness for such diverse low‐probability high‐impact crises can best be included in a wider educative approach. Terrorism crises call for fast information updates that, using a multi‐channel approach, can be tailored to fit different needs and (social) media habits.  相似文献   
9.
When deuterated methanol (CD3OH) and dioxygen mixtures are coadsorbed at Cu(110) surfaces at room temperature and above, the main reaction product can be switched between formaldehyde and formate by changing the mixture composition. For oxygen-rich mixtures formaldehyde is the major product but when methanol is in 5 : 1 excess only formate is produced. It is proposed that the reaction mechanism is controlled by the microscopic structure of the surface: when the reactants are adsorbed sequentially, separate islands of oxygen and methoxy develop which inhibit further oxidation but when reactants are coadsorbed a homogeneous mixture of adsorbates is produced creating a facile pathway to formate. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
No abstract available. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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