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991.
Masaya IGASE Chung Chew HWANG Matt COFFEY Masaru OKUDA Shunsuke NOGUCHI Takuya MIZUNO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):541-548
Oncolytic virotherapy is a new strategy for cancer treatment for humans and
dogs. Reovirus has been proven to be a potent oncolytic virus in human medicine. Our
laboratory has previously reported that canine mast cell tumor and canine lymphoma were
susceptible to reovirus. In this study, canine solid tumor cell lines (mammary gland
tumor, osteosarcoma and malignant melanoma) were tested to determine their susceptibility
towards reovirus. We demonstrated that reovirus induces more than 50% cell death in three
canine mammary gland tumors and one canine malignant melanoma cell line. The
reovirus-induced cell death occurred via the activation of caspase 3. Ras activation has
been shown to be one of the important mechanisms of reovirus-susceptibility in human
cancers. However, Ras activation was not related to the reovirus-susceptibility in canine
solid tumor cell lines, which was similar to reports in canine mast cell tumor and canine
lymphoma. The results of this study highly suggest that canine mammary gland tumor and
canine malignant melanoma are also potential candidates for reovirus therapy in veterinary
oncology. 相似文献
992.
Ileal digestibility of nutrients and amino acids in unfermented,fermented soybean meal and canola meal for weaning pigs 下载免费PDF全文
Apparent ileal digestibility (AID) of energy, dry matter, nitrogen and amino acids and standardized ileal digestibility (SID) of nitrogen and amino acids were evaluated in six weanling pigs ((Landrace × Yorkshire) × Duroc)) fed unfermented soybean meal (SM), yeast fermented soybean meal (SMY), bacillus fermented soybean meal (SMB), yeast and bacillus fermented soybean meal (SMYB), canola meal (CM) and nitrogen‐free diet. Pigs having body weights 17.00 ± 0.3 kg were surgically equipped with T‐cannulas of approximately 15 cm prior to the ileo‐cecal junction and randomly allotted to one of five dietary treatments and a nitrogen‐free diet in 6 × 6 Latin squares. AID and SID of nitrogen (N) was greater (P < 0.05) in SMYB and SMB compared with SM and CM. AID and SID of amino acids such as, Lys (lysine) and Phe (phenylalanine) as well as total essential amino acids were greater (P < 0.05) in SMB and tended to be low in CM compared with SM. AID and SID of aspartic acid (Asp) and glycine (Gly) tended to be higher in SMB compared with SM and other diets except CM. In conclusion, fermentation of soybean meal by Bacillus showed better digestibility of amino acid and nutrients. 相似文献
993.
Production of embryogenic tissues and regeneration of transgenic plants in cassava (Manihot esculenta Crantz) 总被引:3,自引:0,他引:3
Nigel J. Taylor Munyaradzi V. Masona Rosa Carcamo Thao Ho Christian Schöpke Claude M. Fauquet 《Euphytica》2001,120(1):25-34
Disorganised embryogenic tissues have been utilised as target tissues for transgene insertion and transgenic plant regeneration
in cassava (Manihot esculenta). The production of friable embryogenic callus in fourteen geographically diverse cassava cultivars, from which eleven were
established as embryogenic suspension cultures, is reported. Embryogenic tissues were similar in nature in all cultivars tested
although there was variation in the time required to generate friable callus and the growth rates of suspension cultures.
Regeneration of plants has been achieved from eight cultivars but varied significantly in efficiency, with cv. TMS 60444and
Line 2 from Zimbabwe being the most responsive. Tissues from the remaining eight cultivars became arrested at globular and
torpedo stages of regeneration indicating that they most likely process an inherent ability to produce plants but require
further research to allow this to be realised. Significant numbers of transgenic plants containing transgenes for putative
resistance to important viral diseases of cassava in addition to visual marker genes have been regenerated. Transgenic plants
from three the cultivars TMS 60444, Bonoua Rouge and M.Col 1505 were recovered after particle bombardment of embryogenic suspension
cultures. Correlation's have been made between abnormal leaf morphology and plant vigour with the use of embryogenic suspension
cultures for transgene insertion. As an result friable embryogenic callus is now being successfully utilsed as the target
tissue for genetic transformation and plant regeneration at ILTAB.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
Summary New types of diploids in Brassica crops were synthesized after three consecutive selfing of aneuploids derived from backcrossing of sesquidiploids (2n=29, AAC) with B. campestris (2n=20, AA). The cytogenetic and morphological characteristics of plants with 2n=22, 24 and 40 in the S3 generation were analyzed in order to establish the extent in which these addition and polyploid lines were stabilized. A high frequency of 11II (79.7%), 12II (84.6%) and 20II (100%), were observed at metaphase I of pollen mother cells in 2n=22, 24 and 40 plants, respectively. The chromosome configuration at methaphase II also indicates that a certain level of stability has been attained cytogenetically. Although pollen stainability was relatively high, the seed set percentage was still low. Variation in morphological characteristics indicate the incorporation of one or more chromosome pairs from the C genome of B. oleracea. Other diagnostic characters such as the formation of determinate inflorescence, branching from the base of the stem, and the shift from self-incompatibility to self-compatibility must have resulted from the interaction between A and C genomes. Thus plants with 2n=22, 24 and 40 have been stabilized to some extent and can be developed into new breeding lines of Brassica. It is suggested that limited pollination could be effective in increasing the seed fertility of these plants. 相似文献
995.
Lucimara Chiari Lucas Koshy Naoe Newton Deniz Piovesan Inês Chamel José Cosme Damião Cruz Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Euphytica》2006,150(1-2):141-147
Summary We studied the genetic basis of isoflavone content inheritance in soybean seeds. The progenitors BARC-8 (low isoflavone content), IAC-100 (high isoflavone content), the F1 and F2 populations derived from reciprocal crosses, and backcross populations were analyzed for isoflavone content and composition. Six isoflavones were detected: daidzin (DZ), genistin (GT), glycitin (GC), malonyldaidzin (MDZ), malonylgenistin (MGT) and malonylglycitin (MGC). DZ, GT, MDZ and MGT contents were influenced by the cytoplasm and the nuclear genes of the maternal parent. For this reason, a genetic model was considered that included the cytoplasmic effect and epistasis between nuclear and cytoplasmic genes. Except for GT, the additive effect was the most important one. For GT content the cytoplasmic effect was the most important. Except for MDZ, the epistatic effects were significant for all the isoflavone forms. Our data indicate that genetic improvement for these traits should explore the additive genetic variances in superior lines or the cytoplasmic effect and the epistatic interactions between cytoplasmic and nuclear genes to obtain the largest selection gains. 相似文献
996.
Lucimara Chiari Newton Deniz Piovesan Lucas Koshy Naoe Inês Chamel José José Marcelo Soriano Viana Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Euphytica》2004,138(1):55-60
Isoflavones are a class of compounds present in high amounts in soybean seeds, which can be used for prevention and treatment
of several chronic diseases. Proteins present in soybean seeds are the basis for the high nutritional value and versatility
of this leguminous species in animal and human feeding. The main goals of this work were to estimate heritabilities for isoflavone
contents in soybean seeds and the correlation between isoflavone and protein contents. Commercial variety IAC-100 (high isoflavone
and normal protein contents) and the line BARC-8 (low isoflavone and high protein contents) were crossed, and one single F1 plant derived 97 F2 seeds, which were used to obtain F3 seeds. A sample of F3 seeds from each F2 plant was used for isoflavone determination by HPLC and protein by the Kjeldahl method. Six isoflavone forms were detected:
daidzin, genistin, glycitin, malonyldaidzin, malonylgenistin and malonylglycitin. Total isoflavone contents ranged from 427.92
to 965.89 μg per gram of dry seed and the protein content ranged from 45.17 to 34.95% in BARC-8 and IAC-100, respectively.
Our results indicate that it is possible to select for high isoflavone content in early breeding generations because the broad
sense heritabilities for the contents of the various isoflavone forms were higher than 90%. In addition, high correlation
values among the contents of the individual isoflavone forms were observed (between 0.80 and 0.98). However, negative correlation
values were obtained between isoflavone and protein contents, ranging from −0.51 to −0.37 for the different isoflavone forms.
The correlation value of −0.47 between total isoflavone and protein contents confirmed the negative correlation between these
two parameters, as reported by other authors.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
997.
The risks of Bursaphelenchus xylophilus (pine wood nematode) transfer in relation to wood material were assessed. Combinations of infested and non‐infested adjacent boards, long‐blocks and blocks of Pinus pinaster, simulating assembled pallets, were assessed. For the recipient wood, pieces with natural moisture content (MC), heat‐treatment (56°C for 30 min in the core) and kiln‐drying to <20% MC were tested, along with in‐service boards from pallets. Donor and recipient wood materials were kept in direct contact at 25°C or 10°C, with nine replicates per treatment. Bursaphelenchus xylophilus was found to transfer rapidly at 25°C when the wood had an MC above fibre‐saturation point (>30%). Nematode reproduction was rapid and sustained, gradually declining to zero at 40 weeks. Bursaphelenchus xylophilus did not transfer to kiln‐dried or to in‐service wood with an MC below fibre‐saturation point, or to wood at 10°C. The key factors determining nematode transfer were the ambient temperature, the nematode load of the donor wood and the MC of the recipient wood, with a ‘barrier’ of 20% MC below which it becomes unsuitable for nematode transfer. This finding indicates that there is a limited risk of spread of B. xylophilus in treated and untreated solid wood packaging materials. 相似文献
998.
Lin HS Zhang W Go ML Tringali C Spatafora C Ho PC 《Journal of agricultural and food chemistry》2011,59(4):1072-1077
A simple HPLC method was established to quantify trans-3,4,5,4'-tetramethoxystilbene (MR-4 or DMU-212) in rat plasma. Chromatographic separation was obtained with a reversed-phase HPLC column through an 11 min gradient delivery of a mixture of acetonitrile and water at a flow rate of 1.5 mL/min at 50 °C. The limit of quantification was 15 ng/mL. The intra- and interday precisions in terms of relative standard deviation were <9% at all concentrations. Similarly, the accuracy was good, and the bias rates ranged within ±7%. The pharmacokinetic profiles of MR-4 were subsequently assessed in rats using 2-hydroxypropyl-β-cyclodextrin as a dosing vehicle. Upon intravenous administration, MR-4 displayed moderate clearance (46.5 ± 7.6 mL/min/kg) and terminal elimination half-life (154 ± 80 min). However, the absolute oral bioavailability of MR-4 was low (6.31 ± 3.30%). Future investigation on MR-4 as a chemotherapeutic agent should be focused on colorectal cancers. 相似文献
999.
Lu WC Huang WT Kumaran A Ho CT Hwang LS 《Journal of agricultural and food chemistry》2011,59(11):6214-6220
Proanthocyanidins constitute an important class of polyphenols ubiquitously found in plants. They have been extensively studied for their antioxidant capacity and bioactivity in vitro and in animal models. However, their stability under different pH conditions and in cell culture medium has not been well documented. In the present study, it was observed that proanthocyanidin A2 (PA2) was relatively more stable in acidic condition than in weak alkaline condition. PA2 was also quite unstable in basal-Dulbecco's Modified Eagle medium (b-DMEM medium) at 37 °C. The addition of PA2 to the cell culture medium accelerated its epimerization with a half-life of <15 min, and ethylenediaminetetraacetic acid (EDTA) could not stop the reaction. The results also demonstrated that the major isomers transformed in the weak alkaline condition or cell culture medium at 37 °C were identified as epicatechin-(4β→8; 2β→O→7)-ent-catechin (proanthocyanidin A4) and epicatechin-(4β→6; 2β→O→7)-ent-catechin. The rates of transformation were dependent on the pH or the components of the medium. Therefore, the results obtained for PA2 in the cell culture bioassays, which were usually carried out for 24 h, might not represent the true activity of the original PA2. The stability and transformation of PA2 should be considered when the bioactivity of PA2 is evaluated in a given cell culture system. 相似文献
1000.
Substantial activation of the hepatocyte growth factor (HGF)/c-Met pathway leads to cancer cell scattering and invasion and has been observed in several types of cancers, including prostate and colorectal cancers. The phosphorylation cascade downstream of HGF, particularly PI3K/Akt signaling, regulates epithelial-to-mesenchymal transition (EMT). How this signaling governs EMT and whether specific kinases respond to particular EMT effectors remain unclear. This study found specific increases in Mdm2 and vimentin rather than the coregulation of an array of EMT marker proteins in response to HGF-induced EMT in DU145 prostate cancer cells. Importantly, it was further found that diosgenin abrogated HGF-induced DU145 cell scattering and invasion. Moreover, diosgenin effectively inhibited the HGF-induced increases in Mdm2 and vimentin by down-regulating phosphorylated Akt and mTOR. In summary, the results suggest that diosgenin may be a potential compound for use in prostate cancer therapy to target the major HGF-induced EMT pathway. 相似文献