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41.
Motoshi Hiratsuka Takeshi Toma Nina Mindawati Ika Heriansyah Yasushi Morikawa 《Journal of Forest Research》2005,10(6):487-491
Biomass of a mature man-made forest in West Java, Indonesia, was estimated to evaluate the carbon sequestration potential
of plantation forest in the humid tropics. Twenty plots, each 0.25 ha in area and containing one to six planted species over
40 years of age and with closed canopies, were selected. Trunk dry mass was estimated from trunk diameter, tree height, and
bulk density. Maximum trunk diameter (122 cm) was observed in a 46-year-old Khaya grandifoliola C. DC. tree, and the tallest tree (51 m) was a 46-year-old Shorea selanica (DC.) Blume. The largest trunk biomass (911 Mg ha−1) was achieved in the plot composed of two Khaya spp. Among the plots composed of indigeneous Dipterocarpaceae species, the largest trunk biomass was 635 Mg ha−1. These trunk biomasses were larger than those reported from primary rainforests in Southeast Asia (e.g., 403 Mg ha−1 in East Kalimantan, 522 and 368 Mg ha−1 in Peninsular Malaysia). The large biomass in this forest suggests that, given favorable conditions, man-made forests can
accumulate the quantities of atmospheric carbon that were lost by the logging of primary forests in the humid tropics. 相似文献
42.
Naganobu K Ohigashi Y Akiyoshi T Hagio M Miyamoto T Yamaguchi R 《Veterinary surgery : VS》2006,35(4):377-381
OBJECTIVE: To evaluate the efficacy of percutaneous administration of iohexol into the popliteal lymph node as a non-invasive technique for thoracic duct lymphangiography in dogs. STUDY DESIGN: Experimental study and clinical report. ANIMALS: Normal adult dogs (n=4) and 1 dog with recurrent chylothorax. METHODS: For the experimental study, 4 dogs (weight, 8.4-12.3 kg) had 5-10 mL iohexol injected percutaneously into 1 popliteal lymph node and then thoracic radiographs were taken. Popliteal lymph nodes were examined by histopathology 8 days later. One 25-kg dog with recurrent chylothorax had 25 mL iohexol injected into the right popliteal lymph node followed by thoracic radiography. RESULTS: In experimental dogs, the thoracic duct was best visualized on thoracic radiographs after administration of 10 mL iohexol. Clinically, no abnormalities were identified in the injected limb and except for 1 dog that had large numbers of siderocytes and erythrophagocytic macrophages in the injected lymph node, the histopathologic findings in the other injected popliteal lymph nodes were not different from contralateral nodes. In the clinical case, the thoracic duct was visualized, but there was leakage of iohexol around the node. CONCLUSION: The thoracic duct in dogs can be visualized by lymphography after percutaneous injection of iohexol (1 mL/kg at 2 mL/min) into the popliteal lymph node. CLINICAL RELEVANCE: Percutaneous popliteal lymph node administration of iohexol should be considered as an alternative to mesenteric lymph node injection for radiographic identification of the thoracic duct in dogs. 相似文献
43.
Masuda T Yamada K Maekawa T Takeda Y Yamaguchi H 《Journal of agricultural and food chemistry》2006,54(16):6069-6074
In our studies of the chain-breaking antioxidant mechanism of natural phenols in food components, ferulic acid, a phenolic acid widely distributed in edible plants, especially grain, was investigated. The radical oxidation reaction of a large amount of ethyl linoleate in the presence of the methyl ester of ferulic acid produced four types of peroxides as radical termination products. The isolation and structure determination of the peroxides revealed that they had tricyclic structures which consisted of ethyl linoleate, methyl ferulate, and molecular oxygen. Based on the formation pathway of the products, a radical scavenging reaction occurred at the 3'-position of the ferulate radical with the four types of peroxyl radicals of ethyl linoleate. The produced peroxides subsequently underwent intramolecular Diels-Alder reaction to afford stable tricyclic peroxides. 相似文献
44.
Tomomi Kaku Kei’ichi Baba Toru Taniguchi Manabu Kurita Ken-ichi Konagaya Katsuaki Ishii Teiji Kondo Satoshi Serada Haruka Iizuka Rumi Kaida Teruaki Taji Yoichi Sakata Takahisa Hayashi 《Journal of Wood Science》2012,58(4):281-289
The transgenic expression of Aspergillus xyloglucanase cDNA (AaXEG2) with 35S promoter in the leaves of open field-grown poplars was studied. The level of xyloglucan in the transgenic poplars was decreased to 15–16% in the non-fertile soil (forest-field soil) and to 21–22% in the fertile soil (farming-field soil) compared with that of the wild-type poplars. The leaves exhibited a smaller surface area with more rounded teeth than those of the wild-type plants, similar to the sun leaf variety that was grown in the incubation room and subsequently greenhoused. The majority of total veins with water-conducting vascular bundles were shorter in the leaves of the transgenic poplars than those of the wild type. This decrease in vein length may result from a decrease in xyloglucan during leaf development, from which large numbers of proteins were markedly downregulated in the leaves of the transgenic plants via proteomic analysis. It seems likely that the leaves of the transgenic poplars came to relax the edges of their tooth rather than extend their veins as a result of the loosening of the xyloglucan cellulose networks in the leaves. 相似文献
45.
Takafumi Shimoda Takashi Shirouchi Akira Suzuki Yasushi Morikawa Kozo Nishibori 《Journal of Wood Science》2012,58(4):342-351
The storage of spent maitake culture medium (SMCM) under various conditions was investigated as a potential pretreatment of SMCM for increased ethanol conversion. When SMCM was stored at 25°C for 12?weeks, the glucose yield by enzymatic saccharification increased from 22 to 52%. Selective degradation of lignin and hemicellulose occurred in SMCM during storage. The optimal storage temperature of SMCM was at the active growing temperature of maitake mycelium, which is between 25 and 30°C. Storage of SMCM under anaerobic conditions did not increase the glucose yield compared to non-stored conditions. The glucose yield from the SMCM stored for 4?weeks at 25°C was increased by about 30% with either NaOH or vibrating ball milling pretreatment. After 12?weeks of storage, the glucose yield from SMCM without any other pretreatment was higher than that of non-stored SMCM with additional pretreatments. An ethanol yield of 42.1% was obtained from SMCM stored for 12?weeks by simultaneous saccharification and fermentation, which was comparable to yields after NaOH (41.3%) or vibrating ball milling (44.1%) pretreatments. Therefore, storage of SMCM is a very useful pretreatment for bioethanol production. 相似文献
46.
Tomomi TANAKA Satoshi OHKURA Yoshihiro WAKABAYASHI Takenobu KUROIWA Kiyosuke NAGAI Natsumi ENDO Akira TANAKA Hisanori MATSUI Masami KUSAKA Hiroaki OKAMURA 《The Journal of reproduction and development》2013,59(6):563-568
The aim of the present study was to determine if the estradiol-induced luteinizing
hormone (LH) surge is influenced by the constant exposure to TAK-683, an
investigational metastin/kisspeptin analog, that had been established to depress the
pulsatile gonadotropin-releasing hormone (GnRH) and LH secretion in goats.
Ovariectomized goats subcutaneously received TAK-683 (TAK-683 group, n=6) or vehicle
(control group, n=6) constantly via subcutaneous implantation of an osmotic pump.
Five days after the start of the treatment, estradiol was infused intravenously in
both groups to evaluate the effects on the LH surge. Blood samples were collected at
6-min intervals for 4 h prior to the initiation of either the TAK-683 treatment or
the estradiol infusion, to determine the profiles of pulsatile LH secretion. They
were also collected at 2-h intervals from –4 h to 32 h after the start of estradiol
infusion for analysis of LH surges. The frequency and mean concentrations of LH
pulses in the TAK-683 group were remarkably suppressed 5 days after the start of
TAK-683 treatment compared with those of the control group (P<0.05). On the other
hand, a clear LH surge was observed in all animals of both groups. There were no
significant differences in the LH concentrations for surge peak and the peak time of
the LH surge between the TAK-683 and control groups. These findings suggest that the
effects of continuous exposure to kisspeptin or its analog on the mechanism(s) that
regulates the pulsatile and surge mode secretion of GnRH/LH are different in
goats. 相似文献
47.
Hiroki Matsui Taichi Imai Makoto Kondo Tomomi Ban-Tokuda Yutaka Yamada 《Animal Science Journal》2021,92(1):e13636
Medium-chain fatty acids (MCFAs) have antialgal, antibacterial, antifungal, antiprotozoan, and antiviral activities. However, antibacterial activities of MCFAs in the hindgut of pigs and cattle are still unknown. We report the effects of the supplementation of MCFAs on fecal bacteria of pigs, lactating cows, and Japanese Black calves. Lactobacillus spp., Bifidobacterium spp., eaeA(+) Escherichia coli, Salmonella spp., Campylobacter jejuni, and Clostridium perfringens in the feces of animals were quantified by real-time PCR assay. There was no significant increase or decrease in Lactobacillus spp. and Bifidobacterium spp. in the three animals. In the pig feces, eaeA(+) E. coli was reduced to less than a third in the treatment group (P < 0.01). C. jejuni in the pig feces was also significantly less in the treatment group compared with the control (P < 0.01). In the lactating cow, eaeA(+) E. coli was reduced to one fifth of that in the control (P < 0.01). Salmonella spp. was halved in calf feces (P < 0.01). Thus, a reduction in Gram-negative pathogenic bacteria was observed. In conclusion, supplementation of a MCFA calcium soap in the diet would be beneficial to growing pigs, lactating cow, and calves by reducing pathogenic bacteria. 相似文献
48.
This experiment investigates the changes in the plasma leptin levels of sheep fed a diet of three energy levels (low, moderate and high). Four mature wethers were used for this experiment. For the first 4 weeks, the sheep were fed diets to provide 1.2 times the maintenance metabolizable energy requirements, low energy levels (LE). During the second 4 weeks, the sheep were fed diets to provide 1.5 times the maintenance metabolizable energy requirements, moderate energy levels (ME). During third 4‐week period, the sheep were fed a diet to provide 1.8 times the maintenance metabolizable energy requirements, high energy levels (HE). Body weight was determined every week. Blood samples were collected prior to the morning meal at 3 days intervals throughout the experiment, and plasma leptin, insulin and nonesterified fatty acid (NEFA) concentrations were assayed. Body weight decreased in week 1 after the start of the experiment, it continued to decrease during the LE feeding, but it gradually increased until the end of HE period. Similarly, plasma leptin concentration decreased during LE feeding, but increased during the HE feeding. Additionally, positive correlation was obtained between leptin and insulin or glucose concentrations, whereas no clear relationship with circulating NEFA was observed. In conclusion, it was suggested that plasma leptin concentrations were affected by the metabolizable energy in feed. 相似文献
49.
Rosalina M. LAPITAN Arnel N. DEL BARRIO Osamu KATSUBE Tomomi TOKUDA Edgar A. ORDEN Alberto Y. ROBLES Tsutomu FUJIHARA Libertado C. CRUZ Yukio KANAI 《Animal Science Journal》2004,75(6):549-555
Twenty growing crossbred cattle and crossbred water buffalo (carabao) with an average age of 22 (18–24 months) months were equally distributed into two treatment groups according to species. The animals were fed with the same ration made up of corn silage (50%) + wet brewer's spent grain (30%) + concentrate mixture (20%), and their fattening performance was monitored. The digestibilities of the different nutrients were likewise determined. The economics of raising the animals under intensive production system was calculated. Species differences did not influence total dry matter intake of the animals, when expressed as percentage of the bodyweight and per metabolic body size. There were no significant differences in digestion coefficients of the different nutrients, except for crude protein in crossbred water buffalo and crossbred cattle, although the digestibility of dry matter, organic matter and nitrogen free extract tended to be high in the former than in the latter. Likewise, average daily gain (ADG) was similar, although crossbred water buffalo had numerically higher ADG (828.6 vs 785.5 g) than crossbred cattle during the 6 months feeding. During the first 3 months of feeding (1–90 days), the ADG of crossbred water buffalo was 1066.1 g compared to 940.1 g for crossbred cattle. From 91 to 180 days, the crossbred cattle had slightly higher ADG (630.1 vs 591.1 g) but also the difference was not significant. The return above feed cost was comparable for crossbred cattle and crossbred water buffalo during the first 90 days of feeding. However, extending the feeding period from 91 to 180 days , income over feed cost was higher (P < 0.05) for crossbred cattle by PhP 5.3/kg gain than crossbred water buffalo. Results showed that crossbred water buffalo could attain similar growth rate with that of crossbred cattle under intensive system, when fed with high quality feed materials. 相似文献
50.
This research presents a simple way to enhance the anti-UV property of bamboo pulp fabric trough in situ synthesis of ZnO particles on the fabric. Bamboo Pulp Fabric was treated by immersion method in Zn(NO3)2 and multi-amide compound (RSD) aqueous solution under hydrothermal condition, then the ZnO particles were grown on the surface of bamboo pulp fabric by in-situ method. In this synthesis RSD was applied as a stabilizer, reactant and dispersant agent, the reaction mechanism was investigated. The ZnO particles were characterized by transmission electron microscope (TEM), Xray diffraction (XRD) and ultraviolet/visible light spectrophotometer. The anti-UV property of Bamboo Pulp Fabric was characterized by measuring its UPF. The results indicated that the diameter of ZnO is about 150 nm, the length is about 600 nm. The Bamboo Pulp Fabric treated with ZnO particles showed good anti-UV property and its UPF can reach to 83.59. After washing for 20 times, it can also keep good anti-UV property. 相似文献