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排序方式: 共有159条查询结果,搜索用时 15 毫秒
1.
PM Visscher 《遗传、选种与进化》1995,27(4):335-345
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寡毛实蝇属三新种:(双翅目:实蝇科) 总被引:1,自引:0,他引:1
本文记述的3新种,即广西实蝇Dacus(Zeugodacus)guangxianus、近黑颜实蝇D.(Zeugodacus)parater和那大实蝇D.(Asiadacus)nadanus,是1982-1985年在南方各地果园中用诱蝇酮(cue-lure)诱获的,寄主不明。所有模式标本均存放于北京农业部植物检疫实验所。在此谨向提供标本的同志致谢。 相似文献
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M. W. Service 《Entomologia Experimentalis et Applicata》1984,35(1):27-32
Very simply constructed aquatic sticky light traps employing a chemical solution emitting a bright light attracted large numbers of all larval instars, but few pupae of Aedes cantans in trials in England. During April numbers of larvae per trap ranged from 73±14.2 to 163±19.9, whereas dipping with a ladle yielded only 6.9±5.5 to 11.8±7.7 larvae/dip. The traps were also effective in sampling larvae of Culiseta morsitans and in Sierra Leone larvae of Aedes aegypti. It was concluded that sticky light traps could be valuable in sampling relative numbers of mosquito larvae and merited further evaluation.
Résumé Des pièges adhésifs lumineux faciles à réaliser sont construits pour les captures des larves de moustiques. Ils sont formés de paires de boîtes de Pétri en plastique contenant une solution émettrice de lumière provenant de bâtons lumineux chimiques Cyalume®. Chaque piège est recouvert d'une feuille de plastique de 16×16 cm enduite d'une substance qui reste adhésive sous l'eau. Les larves de moustiques attirées vers la source lumineuse viennent se coller à la feuille adhésive.Ces pièges ont été utilisés avec succès en Angleterre pour l'échantillonnage de tous les stades larvaires d'Aedes cantans, mais pas avec le même efficacité pour les nymphes. Des tests plus restreints ont montré que la technique était également utilisable pour les larves de Culiseta morsitans. Les nombres moyens d'A. cantans capturés pendant une piode de 12 h (73±14,2–163±19,9) étaient supérieux à ceux obtenus en plongeant une louche (6,9±5,5–11,8±7,7). En utilisant les pièges adhésifs lumineux, les captures moyennes de C. morsitans étaient également supérieures (12,6±4,7–35,8±8,9) contre (5,7±6,1–8,9±7,8) avec la méthode de la louche.En Sierra Leone, des stades larvaires immatures d'A. aegypti se développant dans des containers de stockage d'eau ont également pu être capturés à l'aide de ces pièges.Bien qu'une évaluation plus poussée soit encore nécessaire, il ne fait aucun doute que ces pièges adhésifs lumineux aient un intérêt considérable pour l'échantillonnage larvaire dans les sites inaccessibles, tels que les trous d'arbres ou les trous de crabes, où les méthodes d'échantillonage classiques sont souvent d'un emploi difficile.相似文献
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PM Cala 《The Journal of general physiology》1977,69(5):537-552
The nucleated high K, low Na red blood cells of the winter flounder demonstrated a volume regulatory response subsequent to osmotic swelling or shrinkage. During volume regulation the net water flow was secondary to net inorganic cation flux. Volume regulation the net water flow was secondary to net inorganic cation flux. Volume regulation after osmotic swelling is referred to as regulatory volume decrease (RVD) and was characterized by net K and water loss. Since the electrochemical gradient for K is directed out of the cell there is no need to invoke active processes to explain RVD. When osmotically shrunken, the flounder erythrocyte demonstrated a regulatory volume increase (RVI) back toward control cell volume. The water movements characteristic of RVI were a consequence of net cellular NaCl and KCl uptake with Na accounting for 75 percent of the increase in intracellular cation content. Since the Na electrochemical gradient is directed into the cell, net Na uptake was the result of Na flux via dissipative pathways. The addition of 10(-4)M ouabain to suspensions of flounder erythrocytes was without effect upon net water movements during volume regulation. The presence of ouabain did however lead to a decreased ration of intracellular K:Na. Analysis of net Na and K fluxes in the presence and absence of ouabain led to the conclusion that Na and K fluxes via both conservative and dissipative pathways are increased in response to osmotic swelling or shrinkage. In addition, the Na and K flux rate through both pump and leak pathways decreased in a parallel fashion as cell volume was regulated. Taken as a whole, the Na and K movements through the flounder erythrocyte membrane demonstrated a functional dependence during volume regulation. 相似文献
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Intrapopulation foraging niche variation between phenotypes and genotypes of Spirit bear populations
Christina N. Service Travis Ingram Thomas E. Reimchen Chris T. Darimont 《Ecology and evolution》2021,11(10):5025
Foraging niche variation within a species can contribute to the maintenance of phenotypic diversity. The multiniche model posits that phenotypes occupying different niches can contribute to the maintenance of balanced polymorphisms. Using coastal populations of black bears (Ursus americanus kermodei) from British Columbia, Canada, we examined potential foraging niche divergence between phenotypes (black and white “Spirit” coat color) and between genotypes (black‐coated homozygote and heterozygous). We applied the Bayesian multivariate models, with biotracers of diet (δ13C and δ15N) together comprising the response variable, to draw inference about foraging niche variation. Variance–covariance matrices from multivariate linear mixed‐effect models were visualized as the Bayesian standard ellipses in δ13C and δ15N isotopic space to assess potential seasonal and annual niche variation between phenotypes and genotypes. We did not detect a difference in annual isotopic foraging niche area in comparisons between genotypes or phenotypes. Consistent with previous field experimental and isotopic analyses, however, we found that white phenotype Spirit bears were modestly more enriched in δ15N during the fall foraging season, though with our modest sample sizes these results were not significant. Although also not statistically significant, variation in isotopic niches between genotypes revealed that heterozygotes were moderately more enriched in δ13C along hair segments grown during fall foraging compared with black‐coated homozygotes. To the extent to which the pattern of elevated δ15N and δ13C may signal the consumption of salmon (Oncorhynchus spp.), as well as the influence of salmon consumption on reproductive fitness, these results suggest that black‐coated heterozygotes could have a minor selective advantage in the fall compared with black‐coated homozygotes. More broadly, our multivariate approach, coupled with knowledge of genetic variation underlying a polymorphic trait, provides new insight into the potential role of a multiniche mechanism in maintaining this rare morph of conservation priority in Canada''s Great Bear Rainforest and could offer new understanding into polymorphisms in other systems. 相似文献
7.
L. Duchemin D. Mitton E. Jolivet J. D. Laredo Laboratoire de Radiologie Expérimentale CNRS UMR Paris France Service de Radiologie Ostéo-Articulaire H?pital Lariboisière AP-HP Paris France & W. Skalli Laboratoire de Biomécanique ENSAM CNRS UMR Paris France 《Computer methods in biomechanics and biomedical engineering》2013,16(2):105-111
In order to reduce the socio-economic burden induced by osteoporotic hip fractures, finite element models have been evaluated as an additional diagnostic tool for fracture prediction. For a future clinical application, the challenge is to reach the best compromise between model relevance and computing time. Based on this consideration, the current study focused on the development and validation of a subject-specific FE-model using an original parameterised generic model and a specific personalization method. A total of 39 human femurs were tested to failure under a quasi-static compression in stance configuration. The corresponding FE-models were generated and for each specimen the numerical fracture load (F FEM) was compared with the experimental value (F EXP), resulting in a significant correlation (F EXP = 1.006 F FEM with r 2 = 0.87 and SEE = 1220 N, p < 0.05) obtained with a reasonable computing time (30 mn). Further in vivo study should confirm the ability of this FE-model to improve the fracture risk prediction. 相似文献
8.
Uxmal and Tulum are two important Mayan sites in the Yucatan peninsula. The buildings are mainly composed of limestone and grey/black discoloration is seen on exposed walls and copious greenish biofilms on inner walls. The principal microorganisms detected on interior walls at both Uxmal and Tulum were cyanobacteria; heterotrophic bacteria and filamentous fungi were also present. A dark‐pigmented mitosporic fungus and Bacillus cereus, both isolated from Uxmal, were shown to be acidogenic in laboratory cultures. Cyanobacteria belonging to rock‐degrading genera Synechocystis and Gloeocapsa were identified at both sites. Surface analysis previously showed that calcium ions were present in the biofilms on buildings at Uxmal and Tulum, suggesting the deposition of biosolubilized stone. Apart from their potential to degrade the substrate, the coccoid cyanobacteria supply organic nutrients for bacteria and fungi, which can produce organic acids, further increasing stone degradation. 相似文献
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Carvajal-Carmona LG Ophoff R Service S Hartiala J Molina J Leon P Ospina J Bedoya G Freimer N Ruiz-Linares A 《Human genetics》2003,112(5-6):534-541
We report a comparative genetic characterization of two population isolates with parallel demographic histories: the Central Valley of Costa Rica (CVCR) and Antioquia (in northwest Colombia). The analysis of mtDNA, Y-chromosome and autosomal polymorphisms shows that Antioquia and the CVCR are genetically very similar, indicating that closely related parental populations founded these two isolates. In both populations, the male ancestry is predominantly European, whereas the female ancestry is mostly Amerind. In agreement with their isolation, the Amerindian mtDNA diversity of Antioquia and the CVCR is typical of ethnically-defined native populations and is markedly lower than in other Latin American populations. A comparison of linkage disequilibrium (LD) at 18 marker pairs in Antioquia and the CVCR shows that markers in LD in both populations are located at short genetic distances (相似文献