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411.
Pycnidiospores of Phyllosticta ampelicida, the causal agent of black rot of grape, were found to germinate only on substrata on which they were firmly attached. Such surfaces were poorly wettable and had advancing contact angles (straight thetaa) formed by a water drop of >80°, e.g., grape leaf, polystyrene, Teflon, polycarbonate, collodion, and glass treated with the silanes n-octadecyltrichlorosilane, dimethyldichlorosilane, or diphenyldichlorosilane. When pycnidiospores were deposited on more wettable surfaces they did not attach firmly and did not germinate. Such highly wettable surfaces had straight thetaa = 40° and were represented by heat-treated glass, cellophane, nutrient- and water-agars, polystyrene treated with UV-irradiation or sulfuric acid, and glass silanized with n-2-aminoethyl-3-aminopropyltrimethoxysilane, n-(trimethoxysilylpropyl)ethylenediamine triacetic acid trisodium, or 3-aminopropyltriethoxysilane. Adhesion of pycnidiospores was assessed with and without a hydraulic shearing force. Pycnidiospore adhesion occurred over several minutes in distilled deionized water, unless it was first acidified, which decreased attachment time to <0.03 s. Attachment of pycnidiospores treated with sodium azide, formaldehyde, or boiled in water for 10 min was similar to nontreated conidia. Possible mechanisms of adhesion of the conidia to surfaces include hydrophobic and ionic interactions. 相似文献
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AbstractAtmospheric particulate samples were collected during three typhoons in 2006 (Chanchu, Bilis, and Kaemi) from Dongshan and Pingtan Islands along the coastal areas of Fujian Province and were analyzed for organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The observations were divided into three periods, namely, pre-typhoon, typhoon, and post-typhoon, to analyze the variations in POP concentrations. The results showed that the PCB and OCP concentrations had daily variations during the pre-typhoon period, while different variation trends were observed during the typhoon periods. The concentrations of those contaminants increased dramatically during typhoon Chanchu (the total concentrations of PCBs and OCPs increased 25 and 24 times, respectively), whereas those values decreased slightly during the typhoon Bilis and Kaemi. However, POPs levels all decreased noticeably during the three post-typhoon periods due to heavy rainfall caused by the typhoons. Observations of an ensemble of factors, including the typhoon migration routes, landfall season, air mass origins and meteorological conditions, and the typhoon migration route was the dominant factor to cause high levels of POPs during the typhoon Chanchu period. Toxicity assessment indicated that the effect of PCB and OCP during the typhoon period should be a concern, which could pose a high potential health risk to organisms. 相似文献
413.
Jianan Wang Guorui Yang Jie Chen Yunpeng Liu Yuankun Wang Cheng‐Yen Lao Kai Xi Duowen Yang Christopher J. Harris Wei Yan Shujiang Ding Ramachandran Vasant Kumar 《Liver Transplantation》2019,9(38)
Lithium–sulfur batteries are appealing as high‐energy storage systems and hold great application prospects in wearable and portable electronics. However, severe shuttle effects, low sulfur conductivity, and especially poor electrode mechanical flexibility restrict sulfur utilization and loading for practical applications. Herein, high‐flux, flexible, electrospun fibrous membranes are developed, which succeed in integrating three functional units (cathode, interlayer, and separator) into an efficient composite. This structure helps to eliminate negative interface effects, and effectively drives synergistic boosts to polysulfide confinement, electron transfer, and lithium‐ion diffusion. It delivers a high initial capacity of 1501 mA h g?1 and a discharge capacity of 933 mA h g?1 after 400 cycles, with slow capacity attenuation (0.069% per cycle). Even under high sulfur loading (13.2 mg cm?2, electrolyte/sulfur ratio = 6 mL g?1) or in an alternative folded state, this three‐in‐one membrane still exhibits high areal capacity (11.4 mA h cm?2) and exceptional application performance (powering an array of over 30 light‐emitting diodes (LEDs)), highlighting its huge potential in high‐energy flexible devices. 相似文献
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Dorota Juchno Olga Jabłońska Alicja Boroń Roman Kujawa Anna Leska Anna Grabowska Anna Nynca Sylwia Świgońska Magdalena Król Aneta Spóz Natalia Laskowska Miłosz Lao 《Genetica》2014,142(4):351-359
Crosses between 21 triploid hybrid Cobitis females and 19 C. taenia (2n = 48) males led to viable progeny; whereas no embryonic development was observed in crosses with tetraploid males (4n = 98). The ploidy status of 491 progenies randomly selected with flow cytometry (316) or chromosome analysis (175) revealed an average of 55.2 % triploids and 44.8 % tetraploids, but the ratio of 3n versus 4n fish did change during development. In the first 2 days after hatching, approximately 65.1 % of tetraploid larvae were observed. Their number decreased significantly to 30.8 and 6.2 % on average during 2–5 and 10–15 months of life, respectively. The karyotype of tetraploid progeny (4n = 98) included 3n = 74 chromosomes of the parental female and n = 24 of C. taenia male. The number of tetraploid progeny indicated indirectly that about 66 % of eggs from 3n females were fertilized with C. taenia. The rest of the eggs developed clonally via gynogenesis or hemiclonally via hybridogenesis into triploids of the same karyotype structure as parental females. We have documented for the first time that (at least under experimental conditions) tetraploids are commonly formed, but are less viable than triploids, and a ratio similar to what is found under natural conditions is finally attained. The current explanation concerning the ploidy and karyotype structure of the progeny confirms that the eggs of 3n Cobitis females are not only capable of maintaining all chromosomes but are also capable of incorporating the sperm genome, thus creating the potential to produce tetraploids. 相似文献
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The phospholipid composition of erythrocyte membranes from patients with multiple sclerosis (MS) was found to be normal, in agreement with previous reports. The transbilayer asymmetry of the glycerophospholipids in MS red cells was probed using bee venom phospholipase A2 and was also found not to be significantly different from normal. Abnormal membrane glycerophospholipid organisation is therefore not involved in the increased red cell size, osmotic fragility, and electrophoretic mobility associated with MS. 相似文献
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