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81.
82.
The aim of this paper is to improve moisture regain of PET fabrics using a lipase treatment. Effects of nine lipase sources,
lipase activator and nonionic surfactant on moisture regain of PET fabrics are examined. Moisture regains of lipase-treated
samples improve by two times in average compared with untreated and buffer-treated samples. Alkaline treatment creates larger
pitting by more aggressive attack into fiber which is proved by SEM and water contact angle measurement. Moisture regain by
alkaline treatment (0.568 % ± 0.08) does not improve. However, lipase-treatment (L2 treatment) improves moisture regain up
to 2.4 times (1.272 % ± 0.05). Although lipase treatment is more moderate than alkaline treatment, lipase hydrolysis on PET
fabrics improves moisture regain, efficiently. K/S values improved confirm that carboxyl and hydroxyl groups are produced
on the surface of PET fabrics by lipase hydrolysis. Moisture regain and dyeability improve by lipase hydrolysis on PET fabrics. 相似文献
83.
Prediction of internal bond strength in a medium density fiberboard process using multivariate statistical methods and variable selection 总被引:2,自引:1,他引:1
Nicolas André Hyun-Woo Cho Seung Hyun Baek Myong-Kee Jeong Timothy M. Young 《Wood Science and Technology》2008,42(7):521-534
This paper presents new data mining-based multivariate calibration models for predicting internal bond strength from medium
density fiberboard (MDF) process variables. It utilizes genetic algorithms (GA) based variable selection combined with several
calibration methods. By adopting a proper variable selection scheme, the prediction performance can be improved because of
the exclusion of non-informative variable(s). A case study using real plant data showed that the calibration models based
on the process variables selected by GA produced better performance than those without variable selection, with the exception
of the radial basis function (RBF) neural networks model. In particular, the calibration model based on supervised probabilistic
principal component analysis (SPPCA) yielded better performance (only when using GA) than partial least squares (PLS), orthogonal-PLS
(O-PLS), and radial basis function neural networks models. The SPPCA model benefits most from the use of GA-based variable
selection in this case study.
N. André and H.-W. Cho equally contributed to this work. 相似文献
84.
A high molecular weight polyhydroxyamide (PHA) solution in N, N-dimethyl acetamide (DMAc) was prepared from 3,3′-dihydroxybenzidine
and isophthalic chloride (IPC), which was used for spinning PHA fiber. Before spinning, the diffusion property of DMAc into
various coagulants was examined. The fiber was well formed in coagulants such as water/ethanol with a composition of 5/5,
ethanol, and ethanol/isopropanol with a composition of 7/3 and 5/5. However, the PHA fiber spun in the water/ethanol mixture
contained voids. After the fiber spun in ethanol was annealed at over 350°C, the ultimate stress and initial modulus of the
fiber increased from 75.5 MPa and 3.22 GPa to 369 MPa and 29.5 GPa, respectively. These properties of the PHA fiber spun by
the dry spinning method were also enhanced, attaining 154 MPa and 5.56 Gpa, respectively. 相似文献
85.
Emilio del Cacho Margarita Gallego Hyun Soon Lillehoj Joaquín Quílez Erik P Lillehoj Ana Ramo Caridad Sánchez-Acedo 《Veterinary research》2014,45(1):25
Although IL17A is associated with the immunological control of various infectious diseases, its role in host response to Eimeria infections is not well understood. In an effort to better dissect the role of IL17A in host-pathogen interactions in avian coccidiosis, a neutralizing antibody (Ab) to chicken IL17A was used to counteract IL17A bioactivity in vivo. Chickens infected with Eimeria tenella and treated intravenously with IL17A Ab, exhibited reduced intracellular schizont and merozoite development, diminished lesion score, compared with untreated controls. Immunohistological evaluation of cecal lesions in the parasitized tissues indicated reduced migration and maturation of second-generation schizonts and reduced lesions in lamina propria and submucosa. In contrast, untreated and infected chickens had epithelial cells harboring second-generation schizonts, which extend into the submucosa through muscularis mucosa disruptions, maturing into second generation merozoites. Furthermore, IL17A Ab treatment was associated with increased parameters of Th1 immunity (IL2- and IFNγ- producing cells), reduced levels of reactive oxygen species (ROS), and diminished levels of serum matrix metalloproteinase-9 (MMP-9). Finally, schizonts from untreated and infected chickens expressed S100, Wiskott-Aldrich syndrome protein family member 3 (WASF3), and heat shock protein-70 (HSP70) proteins as merozoites matured, whereas the expression of these proteins was absent in IL17A Ab-treated chickens. These results provide the first evidence that the administration of an IL17A neutralizing Ab to E. tenella-infected chickens inhibits the migration of parasitized epithelial cells, markedly reduces the production of ROS and MMP-9, and decreases cecal lesions, suggesting that IL17A might be a potential therapeutic target for coccidiosis control. 相似文献
86.
87.
Joohyeong Lee Yongjin Lee Geun‐Shik Lee Seung Tae Lee Eunsong Lee 《Reproduction in domestic animals》2019,54(9):1258-1264
Spermatogonial stem cells (SSC) are promising resources for genetic preservation and restoration of male germ cells in humans and animals. However, no studies have used SSC as donor nuclei in pig somatic cell nuclear transfer (SCNT). This study investigated the potential for use of porcine SSC as a nuclei donor for SCNT and developmental competence of SSC‐derived cloned embryos. In addition, demecolcine was investigated to determine whether it could prevent rupture of SSC during SCNT. When the potential of SSC to support embryonic development after SCNT was compared with that of foetal fibroblasts (FF), SSC‐derived SCNT embryos showed a higher (p < .05) developmental competence to the blastocyst stage (47.8%) than FF‐derived embryos (25.6%). However, when SSC were used as donor nuclei in the SCNT process, cell fusion rates were lower (p < .05) than when FF were used (61.9% vs. 75.8%). Treatment of SSC with demecolcine significantly (p < .05) decreased rupture of SSC during the SCNT procedure (7.5% vs. 18.8%) and increased fusion of cell‐oocyte couplets compared with no treatment (74.6% vs. 61.6%). In addition, SSC‐derived SCNT embryos showed higher blastocyst formation (48.4%) than FF‐derived embryos without (28.4%) and with demecolcine treatment (17.4%), even after demecolcine treatment. Our results demonstrate that porcine SSC are a desirable donor cell type for production of SCNT pig embryos and that demecolcine increases production efficiency of cloned embryos by inhibiting rupture of nuclei donor SSC during SCNT. 相似文献
88.
89.
Starch-gel electrophoresis was used to resolve nine polymorphic enzyme loci from leaf tissue collected from 20 Korean populations
ofEurya japonica in order to determine differences in allele frequencies between male and female trees. In addition, 84 adults were sampled
and mapped in a population located on Naenaro Island in Korea to examine spatial genetic structure using spatial autocorrelation
analysis. Allele frequencies between males and females gave few contribution to the genetic structuring within populations.
Only nine (5%) of 180 cases were significantly different from both sexes in allele frequencies. On the other hand, Moran'sI was significantly different from the expected value in 31 (23.5%) of 132 cases. In the shortest distance (0<5m),I was significantly positive in 10 (22.7%) of 44 cases. The results indicate that a significant small scale genetic structure
was detected in the population and patch widths were inferred to be approximately 5–7 m. A nonrandom distribution of genotypes
may be indicative of restricted gene flowvia seed and pollen dispersal, and patchy establishments of genetically distinct individuals. These factors are responsible for
shaping population genetic structure ofE. japonica. 相似文献
90.
Cho JY Choi GJ Son SW Jang KS Lim HK Lee SO Sung ND Cho KY Kim JC 《Pest management science》2007,63(9):935-940
BACKGROUND: In a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of Myristica fragrans Houttyn (nutmeg) seeds reduced the development of various plant diseases. The objectives of the present study were to isolate and determine antifungal substances from My. fragrans and to evaluate their antifungal activities. RESULTS: Three antifungal lignans were isolated from the methanol extract of My. fragrans seeds and identified as erythro-austrobailignan-6 (EA6), meso-dihydroguaiaretic acid (MDA) and nectandrin-B (NB). In vitro antimicrobial activity of the three lignans varied according to compound and target species. Alternaria alternata, Colletotrichum coccodes, C. gloeosporioides, Magnaporthe grisea, Agrobacterium tumefaciens, Acidovorax konjaci and Burkholderia glumae were relatively sensitive to the three lignans. In vivo, all three compounds effectively suppressed the development of rice blast and wheat leaf rust. In addition, EA6 and NB were highly active against the development of barley powdery mildew and tomato late blight, respectively. Both MDA and NB also moderately inhibited the development of rice sheath blight. CONCLUSION: This is the first study to demonstrate the in vitro and in vivo antifungal activities of the three lignans from My. fragrans against plant pathogenic fungi. 相似文献