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71.
Continuous photografting/crosslinking of polyethyleneglycol dimethacrylate oligomers onto cotton using a water-soluble benzophenone
photoinitiator was investigated. Photografting increased with increasing irradiation dose, oligomer concentration and photoinitiator
concentration. Maximum grafting efficiency of DM 400 and 600 were 83% and 79%, respectively. The photografting increased the
wrinkle resistance of cotton implying surface crosslinking of cotton. Both surface crosslinking and bulk crosslinking of cotton
were accomplished via dual curing of a mixed formulation containing both a thermally curable component (BTCA/SHP) and a UV-curable
component. The wrinkle resistance of the crosslinked cotton was found to be higher when cured by thermal curing after UV curing
rather than by UV curing after thermal curing due to the facile post-polymerization of the UV active component. The presence
of crosslinks in the dually crosslinked cotton was verified with FT-IR and thermogravimetric analysis. 相似文献
72.
大豆单交及三交组合方式与后代优良品系入选机率的关系 总被引:1,自引:1,他引:1
为了进一步提高大豆育种研究水平,加快高产、抗病、优质大豆新品种选育进程,对1971~1982年11年的亲本选配及组合配制方式进行了分析,对三交组合即当地良种×(当地良种×外引良种)F_1选出的优良品种及品系的统计分析表明:三交组合较单交组合选出的优良品种及品系机率高,且丰产性能、抗病性能优于生产品种。绥农4、绥农5、绥农6、绥农8号四个大豆新品种均是以三交组合方式选育成功的。育种理论分析、经验和实践都表明三交组合方式值得提倡。 相似文献
73.
Dispersant-free PTT dyeing of temporarily solubilized azo disperse dyes based on pyridone moiety which contain β-sulfatoethylsulfonyl
group was investigated. The dyes were successfully applied to PTT without the use of dispersants. The color yields of the
dyes on PTT fabric were dependent on dyeing pH as well as dyeing temperature. The optimum results were obtained at pH 5–6
and 110 °C. The dyes showed alkali-clearing property and exhibited good to excellent fastness on the PTT fabric. The COD levels
of the dyeing effluent from the temporarily solubilized disperse dyes were much smaller than those from commercial disperse
dye. 相似文献
74.
Buk-Gu Heo Sang-Uk Chon Yun-Jum Park Jong-Hyang Bae Su-Min Park Yong-Seo Park Hong-Gi Jang Shela Gorinstein 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(4):257-263
This study was conducted to determine the antiproliferative activity of 24 Korean wild vegetables. The methanol extracts of
these wild vegetables were used against lung, breast, colon and gastric cancer cells, and the results were assessed by MTT
assay. It was found that at the extract concentration of 400 mgL−1 14 plants exercised antiproliferative activity over 80% against the lung cancer cells, one plant among six—against breast
cancer cells, and two plants among six—against colon cancer cells, respectively. Eighteen wild vegetables had the hyperplasia
inhibition activity against gastric cancer cells over 23.6% at all extract concentrations, however, only six plants had the
antiproliferative activity over 80% in 600 mgL−1. It was found that the extracts from Youngia sonchifolia, Synurus deltoides, Syneilesis palmata, and Cephalonoplos segetum, in concentration of 400 mgL−1 inhibited the hyperplasia of lung cancer cells over 95% and Angelica gigas—both lung and colon cancer cells over 95%. In conclusion, the studied wild vegetables’ methanol extracts possess dose dependent
antiproliferative properties, based on their bioactive compounds, mainly polyphenols, but some of them as Hypericum ascyron against lung cancer are not effective and even course harm. 相似文献
75.
Cho JY Kim HY Choi GJ Jang KS Lim HK Lim CH Cho KY Kim JC 《Pest management science》2006,62(5):414-418
The methanol extract of stems of Catalpa ovata G Don exhibits potent in vivo antifungal activity against Magnaporthe grisea (Hebert) Barr (rice blast) on rice plants, Botrytis cinerea Pers ex Fr (tomato grey mould) and Phytophthora infestans (Mont) de Bary (tomato late blight) on tomato plants, Puccinia recondita Rob ex Desm (wheat leaf rust) on wheat plants and Blumeria graminis (DC) Speer f. sp. hordei Marchal (barley powdery mildew) on barley plants. An antifungal substance was isolated and identified as dehydro-alpha-lapachone from mass and nuclear magnetic resonance spectral data. It completely inhibited the mycelial growth of B. cinerea, Colletotrichum acutatum Simmonds, Colletotrichum gloeosporioides Simmonds, M. grisea and Pythium ultimum Trow over a range of 0.4-33.3 mg litre(-1). It also controlled the development of rice blast, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose (Colletotrichum coccodes (Wallr) S Hughes). The chemical was particularly effective in suppressing red pepper anthracnose by 95% at a concentration of 125 mg litre(-1). 相似文献
76.
荒漠绿洲节水灌溉制度及效益评价 总被引:1,自引:0,他引:1
本文针对额济纳荒漠绿洲缺水特点 ,根据其自然条件 ,定期观测土壤水分动态变化 ,参照当地和周边地区的灌溉经验 ,推求出棉田的需水量 ,确定其灌溉制度 ,并对其效益进行了初步评价。 相似文献
77.
Mi-Young Yoon Young Sup Kim Shi Yong Ryu Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Byeongjin Cha Seong-Sook Han Jin-Cheol Kim 《Pesticide biochemistry and physiology》2011,101(2):118-124
Blast is considered the most important fungal disease of rice due to its wide distribution and destructiveness under favorable conditions. Development of new effective and environmentally benign agents against the causal pathogen, Magnaporthe oryzae, is of great interest. In the course of a search for natural antifungal compounds in medicinal plants, we found that the methanol extract of Angelica gigas roots showed a potent control efficacy against rice blast caused by M. oryzae. We isolated antifungal coumarins from the extract, and they were identified as decursin and decursinol angelate. Antifungal activities of these compounds, along with kasugamycin, were tested on M. oryzae in vivo and in vitro. In an in vivo assay, the three compounds effectively suppressed the development of rice blast at concentrations more than 100 μg/mL. Coumarins showed relatively weak inhibitory effect on fungal mycelial growth when compared to kasugamycin. However, they strongly inhibited M. oryzae spore germination, which was not observed in kasugamycin treatments. This is the first report demonstrating that decursinol angelate can provide control against rice blast and that the two coumarins inhibit M. oryzae spore germination. In addition, the wettable powder formulation of the crude extract of A. gigas prohibited the development of blast symptoms on rice plants more effectively than liquid concentrate formulation of kasugamin, a commercial fungicide. Based on our study, we propose that coumarin compounds as well as the A. gigas root crude extract can be used as natural, benign fungicides for controlling rice blast. 相似文献
78.
Heon Woong Kim Sung Ryong Kim Young Min Lee Hwan Hee Jang Jung Bong Kim 《Potato Research》2018,61(1):1-17
Anthocyanin concentration and composition and the effect of steaming and baking on these were evaluated in tubers of Korean red- and purple-fleshed potato cultivars and breeding clones using liquid chromatography with diode array detection and electrospray ionization-mass spectrometry (LC-DAD-ESI-MS). Twenty-six anthocyanins were isolated, of which 24 were identified. Remarkably, five cis isomers were identified, of which four, viz., cis-petanin, cis-peonanin, petunidin 3-cis-caffeoylrutinoside-5-glucoside, and petunidin 3-cis-feruloylrutinoside-5-glucoside, are reported for the first time. Moreover, pelargonidin 3-p-coumaroylrutinoside-5-glucoside (pelanin), peonidin 3-p-coumaroylrutinoside-5-glucoside (peonanin) and petunidin 3-p-coumaroylrutinoside-5-glucoside (petanin) were identified as the principal anthocyanins. We found that the total anthocyanin content of coloured potatoes was decreased by steaming and baking compared with the raw state. In addition, we performed partial least square discriminant analysis (PLS-DA) to discriminate between the analyzed anthocyanins. Cis isomers seemed to play a vital role as a biomarker in the PLS-DA model based on the type of processing and colour of the tubers. 相似文献
79.
Staphylococcus simulans, a coagulase-negative staphylococcal species, can cause several diseases in humans and animals. This report describes a case of dermatosis characterized by broad, well-circumscribed hyperkeratosis and alopecia on the back of a household pygmy hedgehog (Erinaceous albiventris). Quills and exudates were studied by microscopy. The microscopic examination of the exudates collected from the lesion revealed several leukocytes and numerous gram-positive cocci. An aerobic bacterial culture revealed overgrowth of the same gram-positive bacteria. The bacterium was identified as S. simulans by polymerase chain reaction amplification and direct sequencing targeted to the 16S ribosomal RNA gene. This report is the first to show that S. simulans could be related to the dermatitis of hedgehogs. 相似文献
80.
Seong Bin Park Kyoung Kwon In Seok Cha Ho Bin Jang Seong Won Nho Fernand F. Fagutao Young Kyu Kim Jong Earn Yu Tae Sung Jung 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):163-166
A multiplex PCR protocol was established to simultaneously detect major bacterial pathogens in olive flounder (Paralichthys olivaceus) including Edwardsiella (E.) tarda, Streptococcus (S.) parauberis, and S. iniae. The PCR assay was able to detect 0.01 ng of E. tarda, 0.1 ng of S. parauberis, and 1 ng of S. iniae genomic DNA. Furthermore, this technique was found to have high specificity when tested with related bacterial species. This method represents a cheaper, faster, and reliable alternative for identifying major bacterial pathogens in olive flounder, the most important farmed fish in Korea. 相似文献