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排序方式: 共有822条查询结果,搜索用时 15 毫秒
1.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed. 相似文献
2.
Osamu Yamato Hiroyuki Satoh Naoaki Matsuki Kenichiro Ono Masahiro Yamasaki Yoshimitsu Maede 《Journal of veterinary diagnostic investigation》2004,16(1):39-44
In the present study, laboratory techniques were used to diagnose canine GM2-gangliosidosis using blood and cerebrospinal fluid (CSF) that can be collected noninvasively from living individuals. Lysosomal acid beta-hexosaminidase (Hex) was measured spectrofluorometrically using 4-methylumbelliferyl N-acetyl-beta-D-glucosaminide and 4-methylumbelliferyl 7-(6-sulfo-2-acetamido-2-deoxy-beta-D-glucopyranoside) as substrates. Main isoenzymes A and B of Hex in leukocytes were also analyzed using cellulose acetate membrane electrophoresis. GM2-ganglioside in CSF was detected and determined quantitatively by using thin-layer chromatography/enzyme-immunostaining method with anti-GM2-ganglioside antibody. In normal dogs, Hex activities could be determined in leukocytes, serum, and CSF and the total activities were markedly reduced in all the enzyme sources in a dog with Sandhoff disease. Electrophoresis of a leukocyte lysate from a normal dog showed that the Hex A and Hex B were not separated distinctively with formation of a broad band, whereas there were no bands in electrophoresis of a lysate from a dog with Sandhoff disease, showing a deficiency in the total enzyme activity. GM2-ganglioside could be detected and determined quantitatively in as little as 100 microl of canine CSE GM2-ganglioside in CSF in a dog with Sandhoff disease increased to 46 times the normal level. In conclusion, the methods in the present study are useful for diagnosis of canine GM2-gangliosidosis. These techniques enable definitive and early diagnosis of canine GM2-gangliosidosis even if tissues and organs cannot be obtained. 相似文献
3.
Rie Gappa-Adachi Yasuaki Morita Yoshifumi Shimomoto Shigeharu Takeuchi 《Journal of General Plant Pathology》2014,80(1):103-107
Sweet peppers (cv. Tosajishi beauty) with leaf blight symptoms were observed in Kochi Prefecture, 2003. Initially, small spots formed on leaves, and later enlarged to brown to dark brown spots, and eventually blighted leaves fell. Several bacteria that caused the same symptoms were isolated and subsequently reisolated. These bacteria were identified as Pseudomonas cichorii on the basis of bacterial characteristics and the 16S rRNA gene sequence. This is the first report of bacterial leaf blight in the sweet pepper in the world. 相似文献
4.
P type humic acid has absorption bands near 615, 570 and 450mµ in the visible region, and is a common component of many soils in north temperate regions (1, 2, 3). Its unusual spectral characteristics are due to a green fraction (Pg), which can be separated from the humic acid dissolved in aqueous alkali by chromatography on Sephadex or cellulose powder, and is precipitated as a reddish-brown substance on acidification (2). In aqueous alkali, it has λmax at 613, 568, 448, 430 (infl.) and 281mµ. The distribution of Pg in different soils is probably related to the presence of fungal sclerotia. The highest content of Pg in p type humic acid is about 10%. We have now obtained evidence that the characteristic colour of Pg is due to the presence of a derivative of 4,9 - dihydroxyperylene - 3,10 - quinone. 相似文献
5.
Sato D Awad AA Chae SH Yokota T Sugimoto Y Takeuchi Y Yoneyama K 《Journal of agricultural and food chemistry》2003,51(5):1162-1168
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively. 相似文献
6.
Naonori Hamato Osamu Kotake Nagaaki Ono Hiroshi Kurashima Masaru Nakano Yuzuri Iwamoto Yoshihiko Takahashi 《Breeding Science》2014,64(4):427-434
‘Niigata S3’ is a new strawberry (Fragaria × ananassa Duch.) cultivar that is early flowering and possesses high soluble solid content and good coloration. It was selected from a cross between Kei812 (seed parent) and ‘Asuka-Ruby’ (pollen parent). The first harvest date of ‘Niigata S3’ was December 27, 34 days earlier than ‘Echigohime’ and 9 days earlier than ‘Asuka-Ruby’ (means of 2007 and 2008). The marketable yield of ‘Niigata S3’ was 85% of ‘Echigohime’, 107% of ‘Asuka-Ruby’, while the early yield was 145% of ‘Echigohime’, 85% of ‘Asuka-Ruby’ (based on 2007 and 2008 means). The shape of the fruit is long conical, and its skin color medium-red. The fruit skin hardness of ‘Niigata S3’ was 31.5 g/mm2, which was harder than ‘Echigohime’, and its average soluble solid content was 11.4%, which was higher than the values for ‘Echigohime’ and ‘Asuka-Ruby’ (2008). Furthermore, ‘Niigata S3’ did not bear apical overripe fruit. This new cultivar is adaptable to the climatic conditions of Niigata, as well as other regions that experience low winter temperatures and insolation. 相似文献
7.
Junichiro Takeuchi Toshihiko Kawachi Koichi Unami Shigeya Maeda Tomoki Izumi 《Paddy and Water Environment》2009,7(1):33-43
A cell-based distributed watershed model is developed which enables us to simulate the hydrological and hydraulic aspects
of the watershed in a refined fashion. With three-zoned cell profiling, the model is composed of three sub-models; tank model
for a surface water zone, soil moisture model for a surface soil zone, and unconfined shallow groundwater flow model for a
subsurface zone. Inclusion of the soil moisture sub-model modified to reroute the infiltration, routed from the tank sub-model,
into the return flow and the groundwater recharge features the model. The groundwater flow sub-model, numerically approximated
by use of the finite volume method and the implicit time-marching scheme, considers a network of on-farm drainage canals as
internal boundaries, which is an essential need for modeling the watershed including farmlands. Cascade-linking of the three
sub-models in a cell and assembling of all the cells over the entire watershed domain provides the global equations system
to be solved. Applicability of the model is demonstrated with its practical application to a real watershed in that paddy
and upland crop fields take great part of the land-use practice. It is then indicated in a quantified manner that rice farming
significantly contribute as a major groundwater recharger in an irrigation period to fostering and conservation of regional
water resources. Along with appropriately profiling a cell, the model is so versatile and tough that it can be applied without
difficulty to a watershed of diverse terrains and land-uses and the computations can stably be carried out. It is thus concluded
that the model presently developed could be a powerful “watershed simulator” to investigate and assess the time-varying hydro-environmental
properties of a watershed while separating and integrating the hydrological and hydraulic components of particular importance. 相似文献
8.
Yoshimasa Sugiura Yoshirou Takeuchi Makoto Kakinuma Hideomi Amano 《Fisheries Science》2006,72(6):1286-1291
ABSTRACT: The effects of 80% methanol extracts from frozen samples of 41 macroalgae and one sea grass collected in the Ise-Shima region of Japan were investigated on histamine release from rat basophile leukemia cells (RBL-2H3) sensitized with antidinitrophenyl (DNP) IgE and stimulated with DNP-BSA. Of the 21 brown algae, five green and 15 red algae, and one sea grass tested, only extracts from seven brown algae suppressed histamine release from RBL cells, as determined by high-performance liquid chromatography (HPLC) analysis. When the cytotoxic effects of the seven brown algal extracts were investigated by Trypan blue staining, only Eisenia arborea and Sargassum thunbergii did not show cytotoxic effects. Therefore, we conclude that E. arborea and S. thunbergii may contain compounds that have antiallergic effects without inducing cell death. 相似文献
9.
Two 21 day experiments were conducted to determine whether microparticulate diets could be used to substitute for diatoms for raising (Experiment 1) as well as settling and on‐growing (Experiment 2) Haliotis diversicolor supertexta postlarvae. The experiments were conducted in 10 L flow‐through tanks and each diet had three replicate tanks. In experiment 1, three experimental microparticulate diets supplied by a commercial feed company, labelled SF‐15, SF‐15 (T) and JFY‐13–1, were used, and in experiment 2, SF‐15 and SF‐15 (T). Artificial diets were compared to diatoms in terms of supporting growth and survival. The survival rate for experiment 1 was lowest for JFY‐13–1 (0%) and highest for diatoms (12.9±0.8%). The final size of postlarvae fed SF‐15 and SF‐15 (T) was significantly greater than that of postlarvae fed diatoms, 973±193 μm and 996±220 μm compared to 786±141 μm. In experiment 2, a total number of 501 larvae settled onto plates covered with SF‐15, 254 on SF‐15 (T) and 1085 on diatoms. The highest survival rate was 33.1±6.9% for SF‐15 and the lowest was 17.3±5.0% for diatoms. However, the final length of postlarvae fed diatoms was significantly greater than SF‐15 and SF‐15 (T); 1018±379 μm compared to 728±89 μm and 717±90 μm. The artificial micro diets used in this study were comparable to diatoms in terms of grow and survival of postlarval H. diversicolor supertexta. 相似文献
10.
Evidence for ozone formation in human atherosclerotic arteries 总被引:1,自引:0,他引:1
Wentworth P Nieva J Takeuchi C Galve R Wentworth AD Dilley RB DeLaria GA Saven A Babior BM Janda KD Eschenmoser A Lerner RA 《Science (New York, N.Y.)》2003,302(5647):1053-1056
Here, we report evidence for the production of ozone in human disease. Signature products unique to cholesterol ozonolysis are present within atherosclerotic tissue at the time of carotid endarterectomy, suggesting that ozone production occurred during lesion development. Furthermore, advanced atherosclerotic plaques generate ozone when the leukocytes within the diseased arteries are activated in vitro. The steroids produced by cholesterol ozonolysis cause effects that are thought to be critical to the pathogenesis of atherosclerosis, including cytotoxicity, lipid-loading in macrophages, and deformation of the apolipoprotein B-100 secondary structure. We propose the trivial designation "atheronals" for this previously unrecognized class of steroids. 相似文献