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221.
Direct demonstration of macula densa-mediated renin secretion 总被引:10,自引:0,他引:10
An in vitro method has been used to examine whether secretion of renin from the juxtaglomerular apparatus is affected by changes in the sodium chloride concentration of the tubular fluid at the macula densa. Single juxtaglomerular apparatuses were microdissected from rabbits and the tubule segment containing the macula densa was perfused, while simultaneously the entire juxtaglomerular apparatus was superfused, and the fluid was collected for renin measurement. In this preparation, in which influences from renal nerves and local hemodynamic effects are eliminated, a decrease in the tubular sodium chloride concentration at the macula densa results in a prompt stimulation of the renin release rate. 相似文献
222.
Mahbub-E-Sobhani Haque N Salma U Ahmed A 《Pakistan journal of biological sciences: PJBS》2011,14(6):363-374
Traditional medical science has kept the mind separate from the body. Recently people realize the effect of mind on health and psychoneuroimmunology is the new evolved science that describes the interactions between psyche and soma. In this review through a typical psycho-neuro-endocrino-immune network the effects of psychological stress (acute, brief naturalistic and chronic) and relaxation on immune modulation has been shown. From this network Corticotrophin Releasing Factor (CRF), Adrenocorticotrophic Hormone (ACTH), Glucocorticoids (GC), alpha-endorphin and Met-enkephalin are found as important endocrine components and T cells, B cells, monocytes/macrophages, Natural Killer (NK) cells and their cytokines that is Tumor Necrosis Factor-alpha (TNF-alpha), Interferon Gamma (IFN-alpha) and interleukins such as IL-1, IL-2, IL-4, IL-6, IL-10, IL-12 etc. are found as important immune components. Finally, it has been shown that, acute, brief naturalistic and chronic stress have different immune modulatory activities which are harmful to one's homeostasis and relaxation can help to maintain that homeostasis. 相似文献
223.
Joanna Składanowska‐Baryza Agnieszka Ludwiczak Ewa Pruszyńska‐Oszmałek Paweł Kołodziejski Marta Bykowska Marek Stanisz 《Animal Science Journal》2018,89(4):713-721
The analyzed material included 40 hybrid rabbits slaughtered at the age of 90 days. The control group was transported directly after weaning, while the transport group was transported directly prior to slaughter. The experiment was designed to assess the transport stress, carcass and meat quality implications, taking into account the muscle type and sex. The transported animals were characterized by a higher level of blood cortisol, glucose and triglycerides (P < 0.0001), and a lower level of insulin (P < 0.0001) compared to the control group. In the presented study the time post‐mortem affected the pH decline in both rabbit groups (P < 0.0001). The lightness, redness and yellowness of rabbit meat were affected by the transport (P < 0.0001, P = 0.001 and P < 0.0001). The percentage of free water and its share in the total water was higher for the non‐transported rabbits compared to the transported ones (P < 0.0001). Moreover, the meat from the control group was characterized by greater plasticity compared to the transport group (P = 0.003). The chemical composition of rabbit meat was not changed by the effect of transport (P = 0.643–0.979). To conclude, the quality traits of meat from the transported hybrid rabbits clearly indicated the development of dark firm and dry‐like lower quality of meat. 相似文献
224.
Suppressing methane emission and global warming potential from rice fields through intermittent drainage and green biomass amendment 下载免费PDF全文
Winter cover crops are recommended to improve soil quality and carbon sequestration, although their use as green manure can significantly increase methane (CH4) emission from paddy soils. Soil management practices can be used to reduce CH4 emission from paddy soils, but intermittent drainage is regarded as a key practice to reduce CH4 emission and global warming potential (GWP). However, significantly greater emissions of carbon dioxide (CO2) and nitrous oxide (N2O) are expected when large amounts of cover crop biomass are incorporated into soils. In this study, we investigated the effects of midseason drainage on CH4 emission and GWP following incorporation of 0, 3, 6 and 12 Mg/ha of cover crop biomass. Methane, CO2 and N2O emission rates significantly (P < 0.05) increased with higher rates of cover crop biomass incorporation under both irrigation conditions. However, intermittent drainage effectively reduced seasonal CH4 fluxes by ca. 42–46% and GWP by 17–31% compared to continuous flooding. Moreover, there were no significant differences in rice yield between the two water management practices with similar biomass incorporation rates. In conclusion, intermittent drainage and incorporation of 3 Mg/ha of green biomass could be a good management option to reduce GWP. 相似文献
225.
Pollination dynamics in a Douglas-fir seed orchard as revealed by pedigree reconstruction 总被引:1,自引:0,他引:1
Ben Sk Lai Tomas Funda Cherdsak Liewlaksaneeyanawin Jaroslav Klápště Annette Van Niejenhuis Cathy Cook Michael U. Stoehr Jack Woods Yousry A. El-Kassaby 《Annals of Forest Science》2010,67(8):808-808
- ? Pollination dynamics was studied in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed orchard using 8 nuclear microsatellite markers and pedigree reconstruction.
- ? The seed orchard consisted of 49 parents (clones). Cone-crop management included bloom delay and supplemental mass pollination (SMP) using 12 internal and 4 external pollen donors.
- ? A random sample of 801 bulk seeds was genotyped for both haploid megagametophyte and corresponding diploid embryo.
- ? Using the parental population’s multilocus genotypes, full pedigree reconstruction generated all the information needed to estimate the maternal, paternal, and parental reproductive success, selfing, pollen contamination, and pollination success of the 4 external pollen donors.
- ? Maternal, paternal, and parental reproductive success varied with 80% of gametes being produced by 23, 45, and 37% of the orchard’s parents, respectively, resulting in a drastically reduced effective population size as compared to the census number (14 vs. 53).
- ? Selfing, pollen contamination, and aggregate SMP success (internal and external) were estimated to be 15.2, 10.4, and 15.0%, respectively.
- ? Full pedigree reconstruction was effective in unraveling the orchard’s pollination dynamics and both female and male reproductive success.
226.
Md Javed Foysal Farhana Momtaz Md Hazrat Ali Muhammad A. B. Siddik Md Reaz Chaklader Md Mahbubur Rahman Md Shamsul Haque Prodhan Anthony Cole 《Journal of fish diseases》2019,42(4):465-475
Aerolysin (aer) is one of the most important and abundant virulence factors in the infection of fish by Aeromonas veronii. A comprehensive study on the molecular characterization and pathogenicity of the aer gene from 34 A. veronii isolates from diseased carp and catfish was carried out and its interactome was analysed to observe the functional correlations between aer and other proteins within the A. veronii network. The PCR‐based amplification of aer from the 34 isolates of A. veronii showed more aer‐positive isolates from catfish with a high pathogenic potential in the in vivo challenge test than the carp fish. The analysis of aer gene sequence from challenged fish revealed significant sequence divergence according to the types and geographical distribution of the fish. The networking analysis of aer from the model A. veronii B565 revealed histidine kinase (cheA) as the most functional interacting partner. The study of the interaction between aer from the experimental A. veronii and cheA demonstrated that the A chain of cheA plays a more important role than the corresponding B chain during contact, and a linker sequence of 15 residues controlled the entire interaction process. Therefore, cheA could be an excellent drug target for controlling A. veronii infection of fish. 相似文献
227.
M. C. Pasikatan E. Haque J. L. Steele C. K. Spillman G. A. Milliken 《Cereal Chemistry》2001,78(6):730-736
In flour milling, a granulation sensor for ground wheat is needed for automatic control of a roller mill's roll gap. A near‐infrared (NIR) reflectance spectrometer was evaluated as a potential granulation sensor of first‐break ground wheat using offline methods. Sixty wheat samples, ground independently, representing six classes and five roller mill gaps, were each used for calibration and validation sets. Partial least squares regression was used to develop the models with cumulative mass of size fraction as the reference value. Combinations of four data pretreatments (log (1/R), baseline correction, unit area normalization, and derivatives) and three wavelength regions (700–1,500, 800–1,600, and 600–1,700 nm) were evaluated. Unit area normalization combined with baseline correction or second derivative yielded models that predicted well each size fraction of first‐break ground wheat. Standard errors of performance of 4.07, 1.75, 1.03, and 1.40 and r2 of 0.93, 0.90, 0.88, and 0.38 for the >1,041‐, >375‐, >240‐, and >136‐μm size ranges, respectively, were obtained for the best model. Results indicate that the granulation sensing technique based on NIR reflectance is ready for online evaluation. 相似文献