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271.
Abstract

This study was carried out to determine the lethality of the entomopathogenic fungus, Lecanicillium longisporum on eggs, young and old nymphs of the greenhouse whitefly, Trialeurodes vaporariorum. Mortality percentage was significantly differed based on stage of T. vaporariorum and conidial concentrations of L. longisporum. Average of the infection level to insect was very low particularly in egg with only 9.81%, even with higher conidial concentrations (1×107 conidia mL-1). Whereas, it was higher in 1st and 2nd instar (46.56%) and 3rd and 4th instars (37.21%). Three parameters were assessed with T. vaporariorum eggs, namely; egg infection, egg hatchability and crawlers emergence. Egg mortality percentages averaged 3.56, 7.14, 9.64, 16.42 and 20.35% with fungal concentrations of 1×103, 1×104, 1×105, 1×106 and 1×107 conidia mL-1, respectively. Daily infection percentages were varied depend upon the conidia concentration where the highest infection rate of eggs was occurred with 1×107. Egg hatch was very high and the mortality among the emerged crawlers was neglectable compared with the control. Efficiency of L. longisporum on whitefly nymphs also was varied based on the insect instar and fungal concentration. Mortality percentages were obviously higher in young nymphs (1st and 2nd instars) than in older ones (3rd and 4th instars). The results indicated that nymphs were highly susceptible to fungal treatment compared with eggs.  相似文献   
272.
Trialeurodes vaporariorum (Homoptera: Aleyrodidae), is a destructive pest of many ornamental and greenhouse crops throughout the world. In this research, effect of essential oil derived from lemon peel, Citrus aurantifolia (Hook.) on mortality of eggs, first-instar nymphs and on adult oviposition of T. vaporariorum (Westwood) was determined under laboratory conditions. Analysis of Citrus aurantifolia essential oil used for insect fumigation by phase gas chromatography revealed the presence of 16 compounds including Limonene (56.6%), β-pinene (16.3%) and α-terpineol (11.3%). Five concentrations of essential oil – 0.002, 0.004, 0.008, 0.016 and 0.032 (μl/ml) – were applied in fumigant toxicity experiments. Greater mortality was observed with increasing dose of essential oil. First-instar nymphs were more sensitive to essential oil treatments compared with eggs and adults that reduced the survival rate of T. vaporariorum by 58, 70 and 56% after treatment of eggs, nymphs and adult, respectively. Based on this study, essential oil derived from C. aurantifolia could be used as an effective and environmentally sustainable bioinsecticide for the control of T. vaporariorum.  相似文献   
273.
The anion–π interactions between Br, Cl, F and H anions and hexafluorobenzene (HFB), 1,2,4,5-tetracyanobenzene (TCB) and tetracyanopyrazine (TCP) have been studied by standard and counterpoise (CP) corrected methods at HF, B3LYP and MP2/6-31+ + G (d,p) levels of theory. The complexation energies were corrected for basis set superposition error (ΔE BSSE) and zero point energy (ΔE BSSE + ZPE). Also, the B3LYP results were corrected by single-point calculation at B3LYP/aug-cc-PVTZ level of theory. Although the CP-corrected method results in higher distances between anions and rings, the standard method gives lower complexation energies. TCP…X series gives higher complexation energies in both CP-corrected and standard methods. Topological analysis of the charge density ρ(r) has been performed by the means of atoms in molecules method on the wave functions obtained at MP2/6-31+ + G (d,p) level of theory. The number and the nature of critical points depend on aromatic ring and anion. Natural bond orbital analysis indicates that nX → π*CC and nX → π*CN interactions are the most important interactions for TCB (and HFB)…X and TCP…X complexes, respectively.  相似文献   
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Glioma is known as one of the most common primary intracranial tumors accounting for four-fifths of malignant brain tumors. There are several biological pathways that play a synergistic, pathophysiological role in glioma, including apoptosis, autophagy, oxidative stress, and cell cycle arrest. According to previous rese arches, the drugs used in the treatment of glioma have been associated with significant limitations. Therefore, improved and/or new therapeutic platforms are required. In this regard, multiple flavonoids and alkaloids have been extensively studied in the treatment of glioma. Berberine is a protoberberine alkaloid with wide range of pharmacological activities, applicable to various pathological conditions. Few studies have reported beneficial roles of berberine in glioma. Berberine exerts its pharmacological functions in glioma by controlling different molecular and cellular pathways. We reviewed the existing knowledge supporting the use of berberine in the treatment of glioma and its effects on molecular and cellular mechanisms.

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277.
Molecular Biology Reports - Several genome-wide association studies showed that a series of genetic variants located at the chromosome 9p21 locus are strongly associated with coronary artery...  相似文献   
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The concept of the integrated biorefinery is critical to developing a robust biorefining industry in the USA. Within this model, the biorefinery will produce fuel as a high-volume output addressing domestic energy needs and biobased chemical products (high-value organics) as an output providing necessary economic support for fuel production. This paper will overview recent developments within two aspects of the integrated biorefinery—the fractionation of biomass into individual process streams and the subsequent conversion of lignin into chemical products. Solvent-based separation of switchgrass, poplar, and mixed feedstocks is being developed as a biorefinery “front end” and will be described as a function of fractionation conditions. Control over the properties and structure of the individual biomass components (carbohydrates and lignin) can be observed by adjusting the fractionation process. Subsequent conversion of the lignin isolated from this fractionation leads to low molecular weight aromatics from selective chemical oxidation. Together, processes such as these provide examples of foundational technology that will contribute to a robust domestic biorefining industry.  相似文献   
280.
Concentration, source, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) were investigated in 22 stations from surface sediments in the areas of anthropogenic pollution in the Klang Strait (Malaysia). The total PAH level in the Klang Strait sediment was 994.02±918.1 µg/kg dw. The highest concentration was observed in stations near the coastline and mouth of the Klang River. These locations were dominated by high molecular weight PAHs. The results showed both pyrogenic and petrogenic sources are main sources of PAHs. Further analyses indicated that PAHs primarily originated from pyrogenic sources (coal combustion and vehicular emissions), with significant contribution from petroleum inputs. Regarding ecological risk estimation, only station 13 was moderately polluted, the rest of the stations suffered rare or slight adverse biological effects with PAH exposure in surface sediment, suggesting that PAHs are not considered as contaminants of concern in the Klang Strait.  相似文献   
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