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211.
ABSTRACT:   The aim of this study was to establish effective procedures for chromosome manipulation in greenling Hexagrammos otakii Jordan et Starks, which has enormous aquacultural potential. To accomplish this, temperature-dependent measurements of the mitotic intervals (τ0) were carried out. The τ0 in this fish was determined by averaging the duration of the first and third embryonic divisions at temperatures ranging 5–25°C. At higher temperatures, eggs developed faster and underwent more identical development. For greenling, τ0 were 341.1 ± 3.60 min at 5°C, 275.5 ± 4.53 min at 10°C, 189.7 ± 6.93 min at 15°C, 99.2 ± 8.27 min at 20°C and 34.2 ± 8.74 min at 25°C. There were strong, negative correlations between the τ0 and water temperatures at all temperatures studied ( Y  = −79.3 X  + 425.3, R 2 = 0.9968, where Y is the mitotic interval and X is the temperature).  相似文献   
212.
Adipose-derived mesenchymal stem cells (AD-MSCs) are abundant in adipose tissue from animals of all ages, are easily isolated, can differentiate into multi-lineage cells, and have a clinical application. This promising potential may only be achieved if the cells are expanding in a large number while maintaining their stemness in sequential passages. In this study, canine AD-MSCs (cAD-MSCs) were individually isolated from five dogs and subjected to proliferative culture with seven sub-passages. The cells at each sub-passage were characterized for properties associated with multipotent MSCs such as proliferation kinetics, expression of MSCs-specific surface markers, expression of molecules associated with self-renewal and differentiation capabilities into mesodermal lineage cells. Proliferation of the cells plateaued at passage 5 by cumulative population doubling level, while cell doubling time gradually increased with passage. MSCs surface markers (CD44, CD90, and CD105) and molecules (Oct 3/4, Sox-2, Nanog and HMGA2) associated with self-renewal were all expressed in the cells between passages 1 to 6 by RT-PCR. In addition, the cells at passage 1, 3 or 6 underwent adipogenic and chondrogenic differentiation under specific induction conditions. However, the level of adipogenic and chondrogenic differentiation was negatively correlated with the number of sub-passage. The present study suggests that sequential sub-passages affect multipotent properties of cAD-MSCs, which should be considered in their therapeutic application in regenerative medicine.  相似文献   
213.
Aloe species, which have been used as medicinal plants, belong to the Asphodelaceae family consisting of 530 species. In this study, genetic diversity and phylogenetic relationships among 40 Aloe species including a putative interspecies hybrid were analyzed using PCR band profiles from eight chloroplast intergenic space markers and nucleotide sequence diversity in the psbK–psbI intergenic region. A phylogenetic tree based on psbK–psbI sequences supported the revised classification of the genus Aloe as polyphyletic with several species be re-allocated into three genera Kumara, Aloidendron, and Aloiampelos. Further, the origin of the putative interspecies Aloe hybrid was characterized through molecular cytogenetics. Fluorescence and genomic insitu hybridization illustrated that the hybrid has a bimodal karyotype with a chromosome complement of 2n = 14, of which complementary halves were derived from two parental species, A. vera and A. arborescens. These findings revealed that the hybrid species was allodiploid. The phylogenetic analysis showed that A. arborescens was the maternal genome donor of the hybrid, as both have identical chloroplast genome sequences. We thus conclude that the allodiploid hybrid should be called A. arborescens × A.vera.  相似文献   
214.
Chronic mucocutaneous candidiasis disease (CMCD) is characterized by recurrent or persistent infections of the skin, nails, and oral and genital mucosae caused by Candida albicans and, to a lesser extent, Staphylococcus aureus, in patients with no other infectious or autoimmune manifestations. We report two genetic etiologies of CMCD: autosomal recessive deficiency in the cytokine receptor, interleukin-17 receptor A (IL-17RA), and autosomal dominant deficiency of the cytokine interleukin-17F (IL-17F). IL-17RA deficiency is complete, abolishing cellular responses to IL-17A and IL-17F homo- and heterodimers. By contrast, IL-17F deficiency is partial, with mutant IL-17F-containing homo- and heterodimers displaying impaired, but not abolished, activity. These experiments of nature indicate that human IL-17A and IL-17F are essential for mucocutaneous immunity against C. albicans, but otherwise largely redundant.  相似文献   
215.
In this article, we demonstrated the preparation of carbon-fiber-reinforced composites using a polyamide 6 (PA6)/thermoplastic polyurethane (TPU) blend, in which the addition of TPU resulted in superior mechanical performances and increased thermal stability. According to various characterization techniques, these results are attributed to an enhanced adhesion and a homogeneous dispersion of long-carbon-fibers (LCFs) with TPU sizing in blended polymer matrix. Above all, dynamic-mechanical thermal analysis (DMTA) measurements clearly show that the dynamic storage modulus (E') of the blend composites is increased by threefold with temperature ranges below and above the glass transition temperature. The presence of LCFs in TPU systems induces effective fiber orientation, exhibiting simultaneous improvements in the tensile strength, flexural strength, and thermal stability.  相似文献   
216.
217.
To evaluate the biological effects of Porphyra tenera (P. tenera), we tried to confirm the possibility that the intake of P. tenera could modulate cognitive and intestinal functions in PM2.5-induced cognitive decline mice. P. tenera attenuated PM2.5-induced learning and memory impairment through antioxidant and anti-inflammatory effects by regulating the mitochondrial function and TLR-initiated NF-κB signaling. In addition, P. tenera effectively alleviated Aβ production/tau phosphorylation by inhibiting the JNK phosphorylation. Also, the bioactive constituents of P. tenera determined the sulfated galactan, mycosporine-like amino acids (MAAs), and chlorophyll derivatives. Moreover, the bioactive compounds of P. tenera by gut fermentation protected against gut dysbiosis and intestinal tight junction damage with a decrease in inflammatory response and short-chain fatty acid production. Based on these results, our findings suggest that P. tenera with sulfated galactan and MAAs is a potential material for cognitive function improvement.  相似文献   
218.
An 8-week feeding trial was conducted to determine the optimal dietary protein level for juvenile marbled flounder. Five semi-purified test diets were formulated to contain different protein levels (CP) including 42.7%, 47.4%, 53.3%, 58.8%, and 64.5% (dry matter), named as CP42.7, CP47.4, CP53.3, CP58.8, and CP64.5, respectively. Five hundred and twenty-five juveniles (6.0 ± 0.1 g) were randomly distributed into 15 tanks (300 L tanks), resulting in 35 fish per tank (n = 3 tanks). Fish were fed the test diets 5 times per day until satiation. The CP58.8 resulted in the highest gain in weight and the best efficiency in feed utilization among the tested protein levels (P < 0.05). Fish fed the CP58.8 diet showed significantly higher whole-body protein and lipid contents than the fish that were fed the other diets (P < 0.05). Fish fed the CP53.3, CP58.8, and CP64.5 diets showed a significantly higher dorsal-muscle lipid content than the fish that were fed the CP42.7 and CP47.4 diets (P < 0.05). The one-slope straight broken-line regression analysis on the results of the thermal growth coefficient and feed conversion ratio indicated that the estimated optimum dietary protein level was 58.8%. Taken together, it is suggested that the dietary protein level of 58.8% is optimal for better growth and high efficiency in feed utilization for the juvenile marbled flounder.  相似文献   
219.
This study was conducted to investigate the effect of steeping conditions of waxy rice, temperatures (15, 25, and 35°C) and time periods (1, 11, and 21 days) on the expansion ratio of gangjung (a traditional Korean oil‐puffed rice snack). Physicochemical properties of waxy rice flour steeped under various conditions and expansion properties of gangjung made of the steeped waxy rice flour were investigated, and multiple regression analyses were applied between those properties to identify major physicochemical factors that optimally predict the expansion ratio of gangjung. As steeping temperature and time periods of waxy rice changed from the lowest to the highest, the expansion ratio of gangjung markedly increased (from 1,022 to 2,533%). Yet, the expansion ratio of the waxy rice sample steeped for 11–21 days at 35°C was not significantly different from the sample steeped for 21 days at 25°C, indicating that the lengthy steeping process for gangjung making can be shortened by increasing the steeping temperature. Physicochemical properties include moisture (γ = 0.85), protein (γ = –0.91), ash (γ = –0.84), potassium (γ = –0.89), magnesium (γ = –0.88), phosphorous (γ = –0.91), peak viscosity (γ = 0.77), and breakdown (γ = 0.94) of steeped waxy rice flour. These properties were highly correlated with expansion ratio (P < 0.01). Multiple regression analysis showed that the expansion ratio of gangjung was predicted successfully by the phosphorous content and breakdown value of steeped waxy rice flour.  相似文献   
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