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91.
J. M. Ellingson L. J. Fleishman E. R. Loew 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,177(5):559-567
The visual pigments and oil droplets in the retina of the diurnal gecko Gonatodes albogularis were examined microspectrophotometrically, and the spectral sensitivity under various adapting conditions was recorded using electrophysiological responses. Three classes of visual pigments were identified, with max at about 542, 475, and 362 nm. Spectral sensitivity functions revealed a broad range of sensitivity, with a peak at approximately 530–540 nm. The cornea and oil droplets were found to be transparent across a range from 350–700 nm, but the lens absorbed short wavelength light below 450 nm. Despite the filtering effect of the lens, a secondary peak in spectral sensitivity to ultraviolet wavelengths was found. These results suggest that G. albogularis does possess the visual mechanisms for discrimination of the color pattern of conspecifics based on either hue or brightness. These findings are discussed in terms of the variation in coloration and social behavior of Gonatodes.Abbreviations
ERG
electroretinogram
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MSP
microspectrophotometry
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UV
ultraviolet
- max
wavelength of maximum absorbance 相似文献
92.
In assessing biological UV-B effects,natural fluctuations of solar radiation should be taken into account 总被引:2,自引:0,他引:2
Daily and weekly fluctuations of PAR, UV-A, and UV-B have been continuously monitored for 5 months in Ancient Korinthos, Greece (37°58 N, 23°0 E) using a calibrated instrument based on 3 sharp band sensors. Daily dose ranged between 521–12 006 kJ m-2 for PAR; 52–1, 239 kJ m-2 for UV-A; and 0.66–22.5 kJ m2 for UV-B. Weekly dose ranged between 16 778-81 788 kJ m-2 for PAR; 1 406–8 517 kJ m-2 for UV-A; and 18–151 kJ m-2 for UV-B. UV-B/PAR and UV-A/PAR ratio distribution, however, does not follow closely PAR fluctuations. Generally, the UV-B/PAR and UV-A/PAR ratios were high in bright light conditions (2.1×10-3, 118×10-3) and low in darker weeks (0.9×10-3, 63×10-3. The UV-B/UV-A ratio exhibits smaller fluctuations with season (20x1×10-3, 12×10-3). Attention is drawn to the effects of sudden changes in ambient radiation and to the ratios of UV-B, UV-A, and PAR. 相似文献
93.
K. Arikawa H. Uchiyama 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1996,178(1):55-61
1. | The ommatidia of the butterfly Papilio have a fused and tiered rhabdom. The distal tier of the rhabdom is made up of four distal photoreceptors (R1–4), whereas the proximal tier is made up of four proximal (R5–8) and one basal photoreceptor cell (R9). |
2. | We first confirmed by light microscopy that the ommatidia of Papilio are not twisted, i.e. have the same spatial organization all about the longitudinal axis. The polarization method, previously applied to the distal tier, hence is applicable to identify the photoreceptor location from the peak angle of the polarization sensitivity. |
3. | We determined the polarization and spectral sensitivity of in total 109 proximal and basal photoreceptors in the lateral looking eye region. All of the photoreceptors were either green or red type, most of which fall into three classes as judged by the peak angles of the polarization sensitivity: around 40°, 150°, and 180° (= 0°) with respect to the dorso-ventral axis. The first two classes are formed by the proximal photoreceptors with straight microvilli oriented at the average angle of 39° (R6, 8) and 144° (R5, 7) respectively, and the third is formed by the basal photoreceptors R9 with straight microvilli oriented at 180° (= 0°). The mean polarization sensitivity (PS = maximal sensitivity/minimal sensitivity) was about 2. |
4. | 75% of the proximal and 48% of the basal photoreceptors were of the red type. |
5. | A single ommatidium of Papilio appears to contain two to four types of spectral receptors. |
94.
95.
Mating in the black soldier fly (BSF) is a visually mediated behaviour that under natural conditions occurs in full sunlight. Artificial light conditions promoting mating by BSF were designed based on the spectral characteristics of the compound eye retina. Electrophysiological measurements revealed that BSF ommatidia contained UV-, blue- and green-sensitive photoreceptor cells, allowing trichromatic vision. An illumination system for indoor breeding based on UV, blue and green LEDs was designed and its efficiency was compared with illumination by fluorescent tubes which have been successfully used to sustain a BSF colony for five years. Illumination by LEDs and the fluorescent tubes yielded equal numbers of egg clutches, however, the LED illumination resulted in significantly more larvae. The possibilities to optimize the current LED illumination system to better approximate the skylight illuminant and potentially optimize the larval yield are discussed. 相似文献
96.
Sachiko Hojo Mikiko Tokiya Masami Mizuki Mikio Miyata Kumiko T. Kanatani Airi Takagi Naomi Tsurikisawa Setsuko Kame Takahiko Katoh Takuya Tsujiuchi Hiroaki Kumano 《Bioelectromagnetics》2016,37(6):353-372
The purpose of the present study was to evaluate the validity and reliability of a Japanese version of an electromagnetic hypersensitivity (EHS) questionnaire, originally developed by Eltiti et al. in the United Kingdom. Using this Japanese EHS questionnaire, surveys were conducted on 1306 controls and 127 self‐selected EHS subjects in Japan. Principal component analysis of controls revealed eight principal symptom groups, namely, nervous, skin‐related, head‐related, auditory and vestibular, musculoskeletal, allergy‐related, sensory, and heart/chest‐related. The reliability of the Japanese EHS questionnaire was confirmed by high to moderate intraclass correlation coefficients in a test–retest analysis, and high Cronbach's α coefficients (0.853–0.953) from each subscale. A comparison of scores of each subscale between self‐selected EHS subjects and age‐ and sex‐matched controls using bivariate logistic regression analysis, Mann–Whitney U‐ and χ2 tests, verified the validity of the questionnaire. This study demonstrated that the Japanese EHS questionnaire is reliable and valid, and can be used for surveillance of EHS individuals in Japan. Furthermore, based on multiple logistic regression and receiver operating characteristic analyses, we propose specific preliminary criteria for screening EHS individuals in Japan. Bioelectromagnetics. 37:353–372, 2016. © 2016 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc. 相似文献
97.
应用干涉型傅里叶变换红外分光光度计及聚乙烯膜作载体,得到了单链、双链DNA、生物素-dUTP及经过缺口翻译参入生物素的DNA探针的红外光谱,观察到Bio-dUTP分子内化学键振动产生的特征吸收谱带。利用差谱技术比较了DNA与生物素标记DNA的差异。Bio-dUTP的特征吸收探测灵敏度可达0.1ng。同时分析了硝酸纤维膜与genescreen的红外透过性质。 相似文献
98.
Spatial pattern of trees in kerangas forest,Sarawak 总被引:1,自引:0,他引:1
The 64 most abundant species (10 cm dbh) in a 400×480 m plot of predominantly kerangas forest in Sarawak were individually investigated for two-dimensional pattern by spectral analysis using the basal areas of trees in 20×20 m contiguous quadrats. All species had individuals in the upper canopy.30 species showed pattern with clumps. The most frequent scales of clump size were between 35 and 55 m across. Patterned species were less abundant in the plot, had a greater proportion of smaller (10–20 cm dbh) trees and had a lower ratio of upper to lower canopy trees than species without pattern.Trend across the plot between dipterocarp and kerangas forest types matched the change in soil from red-yellow podzol (oxisol and ultisol) to medium gleyic and bleached sand podzols (spodosol). However, soil differences and small scale (ca. 50 m) changes in topography did not account for patterns.The scale of pattern matches the size of gaps produced by windthrow. It is suggested that patterned species are light-demanding and grow from seeds in gaps, whereas non-patterned species are shade tolerant, growing within closed forest to sapling size and eventually maturing by filling smaller single tree gaps.D. McC. N. thanks the Deutsche Akademische Austauschdienst for a scholarship and the British Council for travel funds to work at Hamburg. We are grateful to A. Weiscke for entry of the 1963 field records on the computer, T. W. Schneider for helpful discussions and T. C. Whitmore for commenting on earlier drafts.Nomenclature for three species follows Whitmore (1972, 1973), Ng (1978) and Ashton (1982). 相似文献
99.
100.