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121.
The six-flap Z-plasty   总被引:2,自引:0,他引:2  
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122.
The role of microorganisms in litter degradation in arid and semi-arid zones, where soil and water salinization is one of the main factors limiting carbon turnover and decay, remains obscure. Heterostachys ritteriana (Amaranthaceae), a halophyte shrub growing in arid environments such as “Salinas Grandes” (Córdoba, Argentina), appears to be the main source of organic matter in the area. Little is known regarding the microorganisms associated with H. ritteriana, although they are a potential source of enzymes such as cellulolytic ones, which might be important in biotechnological fields such as bioethanol production using ionic liquids. In the present study, by studying the microbiota growing on H. ritteriana leaf litter in “Salinas Grandes,” we isolated the cellulolytic fungus Fusarium equiseti LPSC 1166, which grew and degraded leaf litter under salt stress. The growth of this fungus was a function of the C substrate and the presence of NaCl. Although in vitro the fungus used both soluble and polymeric compounds from H. ritteriana litter and synthesized extracellular β-1,4 endoglucanases, its activity was reduced by 10% NaCl. Based on these results, F. equiseti LPSC 1166 can be described as a halotolerant cellulolytic fungus most probably playing a key role in the decay of H. ritteriana leaf litter in “Salinas Grandes.”  相似文献   
123.
Grapevine moth, Lobesia botrana (Lep. Tortricidae) is a key pest of grape in Iran and other vineyards of the world. In this study, eight constant rearing temperatures (5, 10, 15, 20, 25, 30, 32 and 35 ± 1 °C) along with 60 ± 10% RH and a 16:8 (L:D) h photoperiod were chosen for demographic studies of the grapevine moth. Immature stages were unable to develop when reared at 5 and 35 °C, and the progeny moths were unable to successfully mate at 10, 15 and 32 °C. The overall developmental time of juveniles decreased at 30 °C (from 320.7 ± 3.4 d at 10 °C to 34.2 ± 0.2 d) followed by an increase to 42.5 ± 0.6 d at 32 °C. Based on values of the stable population growth parameters, the temperature of 25 °C was found to be optimal for propagation of grapevine moth. The highest values of the intrinsic rate of increase, gross and net reproductive rates were 0.0719 d??1, 55.5 and 23 females per generation, respectively, at 25 °C. Since jackknife and bootstrap estimates of mean and standard error were mainly similar, both methods may equally be used for uncertainty estimates. Our data suggest that cold storage of grapes will help to control grapevine moth infestations and damage. In many grape growing regions of Iran, the first generation is expected to cause damage. It is expected since our reproductive life table analysis suggests that the hot summer temperatures may restrict pest development during subsequent generations.  相似文献   
124.
In vivo electroporation is increasingly being used to deliver small molecules as well as DNA to tissues. The aim of this study was to quantitatively investigate in vivo electroporation of skeletal muscle, and to determine the threshold for permeabilization. We designed a quantitative method to study in vivo electroporation, by measuring uptake of (51)Cr-EDTA. As electrode configuration influences electric field (E-field) distribution, we developed a method to calculate this. Electroporation of mouse muscle tissue was investigated using either external plate electrodes or internal needle electrodes placed 4 mm apart, and eight pulses of 99 micros duration at a frequency of 1 Hz. The applied voltage to electrode distance ratio was varied from 0 to 2.0 kV/cm. We found that: (1) the threshold for permeabilization of skeletal muscle tissue using short duration pulses was at an applied voltage to electrode distance ratio of 0.53 kV/cm (+/-0.03 kV/cm), corresponding to an E-field of 0.45 kV/cm; (2) there were two phases in the uptake of (51)Cr-EDTA, the first indicating increasing permeabilization and the second indicating beginning irreversible membrane damage; and (3) the calculated E-field distribution was more homogeneous for plate than for needle electrodes, which was reflected in the experimental results.  相似文献   
125.
The most frequent type of N-glycan synthesized by lepidopteran Sf9 cells appears to be fucosylated Man3GlcNAc2,and this has been a limitation for a large scale production and utilization of therapeutic glycoproteins in cultured insect cells. The current knowledge of the protein glycosylation pathway derived from structural studies on recombinant glyco-proteins expressed by using baculovirus vectors. In this work we provide more direct evidence for the sequential events occurring in the processing of endogenous N-glycoproteins of noninfected Sf9 cells. By metabolic labeling with radioactive mannose, we characterized the glycan structures which accumulated in the presence of processing inhibitors (castanospermine and swainsonine) and in the presence of an intracellular trafficking inhibitor (monensin). We thus demonstrated that from the glycan precursor Glc3Man9GlcNAc2 to GlcNAcMan5(Fuc)GlcNAc2 intermediate, the processing pathway in Sf9 cells paralleled the one demonstrated in mammalian cells. By using monensin, we demonstrated the formation of Man3(Fuc)GlcNAc2 from GlcNAcMan3(Fuc)GlcNAc2, a reaction which has not been described in mammalian cells. Our results support the idea that the hexosaminidase activity is of physiological relevance to the glycosylation pathway and is Golgi located.  相似文献   
126.
马加拉山国家公园自建立以来,在自然环境保护方面面临着一些问题。园内住民向来使用药用植物治疗各种疾病,长期依赖周围的植物资源提供食品、房舍、饲料、保健品和其他人文生活的需要。然而,工业化的兴起以及随之而来的人们生活方式的改变,使得利用当地植物作医药的情况不断减少。因此,有必要进行民族植物学研究,把本土植物的利用信息在丧失之前记录下来。调查结果表明,AsparagusadescendensRoxb.,BerberislyciumRoyle(柯杞小檗)和ViolacanescenceWal.exRoxb.只能少量采集,AcaciamodestaWal.,A.nilotica(L.)Delile(阿拉伯胶金合欢),BuxuspipilosaC.K.Schneid.和Dodonaeaviscosa(L.)Jacq.(车桑子)等作为薪材面临砍伐的压力。而GrewiaoptivaDrum.exBurret作为持续利用的饲料和制绳用的种类显示良好的前景  相似文献   
127.
128.
Buds of in vitro-grown shoots of two purple-fleshed potato genotypes were successfully cryopreserved by encapsulation-vitrification (Encap-vitri) and droplet-vitrification (Drop-vitri). Optimal time durations of exposure to PVS2 for shoot regrowth of cryopreserved buds were 5–7 h and 6 h for ‘E03-2677’ and for ‘Blue Congo’, respectively, in Encap-vitri, and 30–50 min and 40 min for the former and the latter, respectively, in Drop-vitri. Higher rates of shoot regrowth were obtained in 1.5–2.0 mm-buds than in 1.0–1.4 mm-ones in Encap-vitri for ‘E03-2677’ and ‘Blue Congo’, while opposite results were found in Drop-vitri. In ‘Blue Congo’, only apical shoot tips survived and developed into shoots, with one shoot produced in one cryopreserved bud in Encap-vitri and Drop-vitri. In ‘E03-2677’, survival and shoot regrowth patterns were similar to those of ‘Blue Congo’ in Encap-vitri. However, both apical and axillary shoot tips survived and developed into two shoots in one bud in Drop-vitri. In ‘E03-2677’, histological observations revealed only apical shoot tips survived following Encap-vitri, while both apical and axillary shoot tips survived following Drop-vitri. Vegetative growth in shoots regenerated from Encap-vitri and Drop-vitri after 3 weeks of post-thaw culture was significantly lower than that from control, but markedly increased after 6 months of post-thaw culture. In both ‘E03-2677’ and ‘Blue Congo’, number of microtubers per shoot, per vessel and ≥3 mm in diameter were significantly greater in shoots regenerated from Encap-vitri than in those from the control. Assessments by ISSR and RAPD of genetic stability did not find any polymorphic bands in regenerants recovered from Encap-vitri and Drop-vitri. To the best of our knowledge, this is the first report on cryopreservation of purple-fleshed potato by vitrification-based procedures. Results reported here would provide valuable basic and technical information on cryopreservation of purple-fleshed potato.  相似文献   
129.
Length–weight relationships (LWRs) are described for 21 fish species belonging to six families from different tributaries of the upland Ganga Basin in India. LWRs for five selected species were unknown to FishBase and new maximum lengths are recorded for 13 species. These results will be useful for fishery research, management and conservation in these tributaries of the Ganga River basin.  相似文献   
130.
The deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales.  相似文献   
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