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41.
Shogo Moriya Shunpei Sato Moongeun Yoon Tomonori Azumaya Shigehiko Urawa Akihisa Urano Syuiti Abe 《Fisheries Science》2009,75(2):359-367
More than 1,000 age-identified chum salmon Oncorhynchus keta collected at 23 stations in the Bering Sea and the North Pacific Ocean in June to July 2003 were used to estimate their origin
of stocks using a DNA microarray developed for analyzing the mitochondrial (mt)DNA haplotypes. The observed haplotype distribution
was nearly the same as that reported previously for fish collected in September 2002 and 2003 in the present surveyed areas.
A conditional maximum-likelihood method for estimation of stock compositions indicated that the Japanese stocks mainly distributed
in north central Bering Sea, whereas the Russian stocks were mainly in western Bering Sea. The North American stocks were
abundant in eastern Bering Sea and around the Aleutian Islands. Such an area-specific stock composition was not significantly
different between mature and immature fish. Thus, the combined results of 2 years suggest that the distribution of chum salmon
is nonrandom in the surveyed areas in summer and autumn, and that fish of the same origin migrate together to the same area
irrespective of age. 相似文献
42.
Keishi Matsuda Shinsuke Torisawa Tomonori Hiraishi Katsutaro Yamamoto 《Fisheries Science》2009,75(1):35-42
In this study, we determined the color vision and spectral sensitivity of pointhead flounder, slime flounder, and red halibut
by recording electrophysiological S-potentials from isolated retinas; this basic data was collected to aid the selection of
appropriate colors and effective wavelengths for selective fishing gear for sustainable fisheries. Four kinds of L-response
and one C-response were recorded in the pointhead flounder and red halibut. Two kinds of L-response were recorded in the slime
flounder. The occurrence of a C-response indicates the possession of color vision. The C-responses show that the pointhead
flounder has superior distinction from blue to yellow, and red halibut has superior distinction from blue and green to red.
The most frequently recorded L-responses indicate high spectral sensitivity at 544 nm in pointhead flounder and 518 nm in
slime flounder and red halibut. All recorded L- and C-responses indicate sensitivity to ultraviolet wavelengths. 相似文献
43.
Kanefumi Kitahara Takako Tanaka Toshihiko Suganuma Tomonori Nagahama 《Cereal Chemistry》1997,74(1):1-6
The raw starch granules from corn, rice, and wheat were hydrolyzed by practically pure glucoamylase (Rhizopus niveus). The bound lipids remaining in the residual starches were investigated, of which the major components of the lipids, free fatty acids (FFA) in corn starch, FFA and phospholipids (PL) in rice starch, and PL in wheat starch were determined. In each case, the bound FFA and PL were decreased to some extent during the initial stage of hydrolysis. During the later stages, the FFA continued to gradually decrease, while the level of PL stabilized. It was interesting that some of the bound lipids were released from the granules upon glucoamylase hydrolysis, differing from the model amylose-lipid complexes. Furthermore, the structures of the residual starches were investigated. The blue value and λmax of the starches were increased by partial hydrolysis of the starch granules using practically pure glucoamylase. Two gel-permeation chromatography analyses revealed that the relative amount of amylose fraction was increased by glucoamylase hydrolysis, and also that the increments were reduced by the defatting of bound lipids. The results suggest that the increase in amylose fraction is attributable to the existence of bound lipids in the granules. 相似文献
44.
45.
Characterization of plant-derived water extractable organic matter by multiple spectroscopic techniques 总被引:1,自引:0,他引:1
Zhongqi He Jingdong Mao C. Wayne Honeycutt Tsutomu Ohno James F. Hunt Barbara J. Cade-Menun 《Biology and Fertility of Soils》2009,45(6):609-616
Water extractable organic matter (WEOM) derived from fresh- or early-stage decomposing soil amendment materials may play an
important role in the process of organic matter accumulation. In this study, eight WEOM samples extracted with a 40:1 (v/w) water to sample ratio from alfalfa (Medicago sativa L.), corn (Zea mays L.), crimson clover (Trifolium incarnatum L.), hairy vetch (Vicia villosa L.), lupin (Lupinus albus L.), soybean (Glycine max L. Merr.), wheat (Triticum aestivum L.), and dairy manure were investigated using ultraviolet (UV)–visible, Fourier transform infrared (FT-IR), solution 31P nuclear magnetic resonance (NMR), and solid state 13C NMR spectroscopies. UV–visible and FT-IR spectra of the plant-derived WEOM samples were typical for natural organic matter,
but possessed less humic-like characteristics than dairy manure-derived WEOM. Solution 31P NMR spectra indicated that WEOM samples extracted from alfalfa, corn, and soybean shoots contained both orthophosphate and
monoester P. Of the monoester P in WEOM from soybean shoot, 70% was phytate P. WEOM from crimson clover, hairy vetch, lupin,
and wheat shoots contained orthophosphate only. The solid-state 13C NMR spectra of the seven plant-derived WEOM samples indicated that they all were primarily composed of sugars, amino acids
or peptides, and low molecular mass carboxylic acids. Carbohydrates were dominant components with very few aromatics present
in these samples. In addition, WEOM from crimson clover and lupin, but not other three leguminous plant WEOM samples, contained
significant asparagine. On the other hand, WEOM from corn and wheat contained less amino acids or peptides. The spectra of
WEOM of dairy manure revealed the presence of significant amounts of nonprotonated carbons and lignin residues, suggesting
humification of the manure-derived WEOM. Significant carbohydrates as well as aromatics were present in this WEOM. The P and
C bonding information for these WEOM samples may be useful for understanding the effects of WEOM on soil nutrient availability
to plants.
Trade or manufacturers' names mentioned in the paper are for information only and do not constitute endorsement, recommendation,
or exclusion by the USDA-ARS. 相似文献
46.
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49.
Kenji Tsuruta Tomonori Kume Hikaru Komatsu Naoko Higashi Toshihiro Umebayashi Tomo’omi Kumagai Kyoichi Otsuki 《Journal of Forest Research》2010,15(6):398-403
Sap flow techniques are practical tools for estimating tree transpiration. Though many previous studies using sap flow techniques
did not consider azimuthal variations of sap flux density (F
d) on xylem trunk to estimate tree transpiration, a few studies reported that ignoring the azimuthal variations in F
d could cause large errors in tree transpiration estimates for some tree species. Therefore, examining azimuthal variations
in F
d for major plantation tree species is critical for estimating tree transpiration. Using the thermal dissipation method, we
examined azimuthal variations in F
d in six trees of Japanese cypress Chamaecyparis obtusa (Sieb. et Zucc.) Endl., which is one of the most common plantation tree species in Japan. We recorded considerable variations
among F
d at four different azimuthal directions. The F
d value for one aspect was more than 100% larger than those for the other aspects. We calculated differences between tree transpiration
estimates based on F
d for one to three azimuthal directions and those based on F
d for four aspects. The differences relative to tree transpiration estimates based on F
d for four aspects were typically 30, 20, and 10% in accordance with the F
d for one, two, and three measurement aspects, respectively. This finding indicates that ignoring azimuthal variations could
cause large errors in tree transpiration estimates for Japanese cypress. 相似文献
50.
Masako Kubo Koji Shimano Hitoshi Sakio Yuji Isagi Keiichi Ohno 《Journal of Forest Research》2010,15(5):337-340
Cercidiphyllum japonicum and C. magnificum are deciduous tree species that produce large numbers of sprouts. They are found mainly in riparian and/or disturbed areas.
C. japonicum is distributed in the montane zone in Japan, whereas C. magnificum is distributed mostly in the subalpine zone of central Japan. However, the two species sometimes coexist, e.g., on the talus
slope at the valley head of the Chichibu Mountains. We investigated differences in sprouting traits in these two species by
comparing class distributions of sprout diameter at breast height (DBH) and heights of individuals on the talus slope. Sprout
DBH and individual height were smaller in C. magnificum as compared to C. japonicum. Moreover, the analysis of the DBH-class distribution of each species indicated that C. magnificum had numerous small sprouts and experienced high mortality, whereas C. japonicum had fewer small sprouts and low mortality. It is likely that the sprouting traits of C. magnificum make it more adapted to severe conditions in the subalpine zone than those of C. japonicum. 相似文献