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181.
The mate choice and mating pattern of a benthic goby Rhinogobius sp. CB (cross band type) were investigated in the Kamo River, Shikoku, Japan. During the breeding season, gravid females assumed a nuptial color and either males or females initiated a courtship display. Males preferentially courted a female of similar size to lead her to his nest, whereas females courted more frequently when they encountered a large male. Eggs in any one nest were always at the same developmental stage. Sampling data of nesting males and females indicated that, in more than half the nests, males gathered more than one female before spawning. In some nests with eggs, two or three females had spent ovaries, indicating that the eggs were laid by multiple females within a short span of time. However, a comparison between the total number of eggs which females would spawn in one nest and the number of eggs actually deposited suggested that eggs were contributed by one female in most nests. This low level of polygyny in spite of multiple female availability is attributed to a limited available spawning area of the nest. 相似文献
182.
Here we report the seed morphology and anatomy of some Nigerian pulses, an investigation that revealed a wide diversity of
characteristics in a small collection of seeds. Although these genera share common features, their anatomical differences
make it possible to generate a key for identification and classification. Sizes ranged from 5 to 7 x 5 x 3 mm forCajanus cajan up to 25 to 30 x 18 x 19 mm forCanavalia ensiformis. Seed colors were monochromatic black/brown to dichromatic eye/mottled (streaked), and surfaces were either smooth-glossy
or puckered. Forms varied from ellipsoid or oblong-ellipsoid to spheroid or reniform, and halos (hilar rims) were either complete
or incomplete. Lens shapes were spot, linear, broadly linear, or deltoid. The hila were elliptic to linear (or in-between),
with sizes ranging from 0.5 to 1.0 mm (Mucuna pruriens) up to 1.5 to 3.0 mm (Phaseolus vulgaris). Their positions could be completely covered, as inP. vulgaris, partially covered and raised above the seed surface (Vigna subterranea), or naked (without any funicular residue) arid level with the surface, as in Gensiformis (Tce1 ). The aril caps were collar-like inLablab purpureus or cushion-like, as inM. pruriens. Palisade cell sizes ranged from 80.7pm inGlycine max to 1733 μm inC. ensiformis (Tce1), and their shapes varied from a uniformly wall-thickened type (T1), to a bulbous-end type (T2), to one with a corrugated structure on the inner wall (T3). Although these anatomical variations exist, they may not warrant demarcation into sub-familiar or generic classifications.
However, we do propose that specific and sub-specific alterations are necessary. 相似文献
183.
184.
Qiao Wang 《Journal of Insect Behavior》2002,15(5):675-687
Zorion guttigerum is a flower-visiting longhorned beetle endemic to New Zealand. Sexual selection of this species in relation to the body size and color form of different sexes was investigated in the field. The population sex ratio, based on censuses of feeding and mating sites (flowers), is male-biased. Females are significantly larger than males. Both sexes have antennae of similar length but the antennal length relative to the elytral length is greater in males than in females, and the antennal length of males increases more with an increase in body size than that of females. Both sexes have dark blue (DB) and yellowish-brown (YB) individuals. Both pair-bonded and solitary males are similar in elytral and antennal length. In pair-bonded males, DB individuals are significantly more numerous than YB ones, but in solitary males, the number of both color forms is similar. Males tend to have territory protection behavior, fighting with and chasing away rival males from feeding and mating sites. Larger males usually win the fight but the size-dependent fighting advantage does not translate into mating success. Male color plays an important role in mating success, with DB males having a significantly better chance to mate than YB males. Furthermore, male body size and color also have interactions in mating success: males of DB color morph obtain a greater mating advantage according to body size. Pair-bonded females are significantly larger and have longer antennae than solitary females, suggesting that males prefer larger females for mating. In addition, females of DB color morph with longer antennae are also preferred by males for mating. The significance of these findings is discussed. 相似文献
185.
江苏下扬子区寒武系-三叠系牙形刺色变指标(CAI)图及其意义 总被引:1,自引:0,他引:1
本文对多年来积累的江苏下扬子区寒武系-三叠系牙形刺CAI材料进行了系统收集和整理,并采用Anita Harris建立的统一标准,编制了本区寒武系-三叠系的5幅牙形刺CAI图;进而结合牙形刺CAI与镜质组反射率(Ro)的对应关系,对上述各系的有机质成熟度进行了评价,对本区海相中、古生界油气勘探具有十分重要的意义。 相似文献
186.
Analysis of Petal Anthocyanins to Investigate Flower Coloration of Zhongyuan (Chinese) and Daikon Island (Japanese) Tree Peony Cultivars 总被引:14,自引:0,他引:14
Liang-Sheng Wang Aya Shiraishi Fumio Hashimoto Noriaki Aoki Keiichi Shimizu Yusuke Sakata 《Journal of plant research》2001,114(1):33-43
Pn, Pg; Pn, Pg > Cy ; Pn, Cy and Pn, Cy > Pg groups. Each group consequently specified significant features among CIELAB color notation and petal pigmentation, being
adequate to characterize tree peony flowers as similar between Zhongyuan and Daikon Island cultivars, thus the cultivars of
the two areas are suggested to be related to one another.
Received 25 April 2000/ Accepted in revised form 21 December 2000 相似文献
187.
Seungdo Kim Taeyeon Hwang Michael Overcash 《The International Journal of Life Cycle Assessment》2001,6(1):35-43
The environmental performance of a color computer monitor is investigated by implementing a Life Cycle Assessment. The goal
of this study is to collect LCI data of foreground systems, to identify hot spots, and to introduce life cycle thinking at
the product design stage. Secondary data are used in the background system, and site-specific data are collected in the foreground
system.
Results show that the use phase is the most contributing phase. The operating mode and the energy saving mode during the overall
use phase contribute to the total by 59% and by 9.9%, respectively. In the production phase, the cathode ray tube assembly
process and the printed circuit board assembly process are the most contributing processes. The sensitivity analysis on the
use pattern scenario shows that the contribution ratio of the use phase ranges from 32% to 84%. Even in the home use case,
which is the best case scenario, the use phase is one of the most contributing processes to the environmental performance
of the color computer monitor. There is no significant difference in the choice of the impact assessment methodologies for
identifying the improvement opportunities.
For the external use of Life Cycle Assessment in a short-run product for the market, it is recommended that Life Cycle Assessment
should be carried out in parallel with the product design stage. It is also necessary to have a pre-existing, in-house database
for a product group in order to accelerate life cycle procedures. 相似文献
188.
A recent examination of color vision in the ringtail lemur produced evidence that these prosimians could make color discriminations consistent with a diagnosis of trichromatic color vision. However, it was unclear if this behavior reflected the presence of three classes of cone or whether lemurs might be able to utilize signals from rods in conjunction with those from only two classes of cone. To resolve that issue, spectral sensitivity functions were obtained from ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus) using a noninvasive electrophysiological procedure, electroretinographic flicker photometry. Results from experiments involving chromatic adaptation indicate that these lemurs routinely have only a single class of cone photopigment in the middle to long wavelengths (peak sensitivity of about 545 nm); they also have a short-wavelengthsensitive cone pigment with peak of about 437 nm. The earlier behavioral results are suggested to have resulted from the ability of lemurs to jointly utilize signals from rods and cones. The cone pigment complements of these lemurs differ distinctly from those seen among the anthropoids. © 1993 Wiley-Liss, Inc. 相似文献
189.
Response of female melon fly, Bactrocera cucurbitae, to host-associated visual and olfactory stimuli 总被引:3,自引:0,他引:3
Jaime C. Piñero Isabel Jácome Roger Vargas & Ronald J. Prokopy† 《Entomologia Experimentalis et Applicata》2006,121(3):261-269
In a series of studies conducted in Hawaii under seminatural conditions, we quantified the response of sexually mature, host‐seeking female melon flies, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), to different types of visual and chemical host‐associated stimuli with the main aim of developing a monitoring device for females. Experiments were conducted using Tangletrap‐coated fruit mimics of either spherical (8 cm diameter) or cylindrical (4.3 cm diameter; 15 cm length) shapes coated with different artificial color pigments both at the ground level and at the tree‐canopy level so as to take into account the foraging behavior of adult melon flies. Females were particularly attracted to objects of spherical shape colored either yellow, white, or orange; these three pigments offered the highest reflectance values. Cucumber (Cucumis sativus L.) (Cucurbitaceae) odor was more attractive to females than odors of three other cultivated host fruit [zucchini, Cucurbita pepo L. var. medullosa Alef. (Cucurbitaceae); papaya, Carica papaya L. (Caricaceae); or tomato Solanum lycopersicum L. (Solanaceae)] or of ivy gourd [Coccinia grandis (L.) Voigt (Cucurbitaceae)], one of the major wild hosts of melon fly in Hawaii. A combination of both visual and olfactory stimuli was needed to elicit high levels of response compared to each stimulus offered alone. We discuss our results in relation to the potential implementation of improved female monitoring and/or attract‐and‐kill strategies for melon flies in Hawaii. 相似文献
190.
《Current biology : CB》2020,30(13):2433-2445.e3