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111.
The light and scanning electron microscopic structure of the filiform lingual papillae was studied in five adult porcupine (three males and two females). The tongue was characterised by a round tip, a rostral median sulcus and a deep lingual fossa which was situated just rostral to a prominent inter-molar eminence corresponding to a torus linguae. The filiform papillae were curved, enclosed a large connective tissue core and were separated by wide inter-papillary zones covered by a thick epithelium. Most filiform papillae had a cylindrical shape, but the rostral and central parts of the tongue contained a number of flat, comb-shaped papillae with rounded tips.  相似文献   
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Fusarin C is a Fusarium mycotoxin that rearranges under reversed phase chromatographic conditions. In this study, the rearrangement of fusarin C was examined in detail, and the formation of fusarins under different conditions was optimized. All relevant fusarins including (10Z)-, (8Z)-, and (6Z)-fusarin C were isolated and identified by NMR. To confirm the involvement of the 2-pyrrolidone ring in the rearrangement of fusarin C, 15-methoxy-fusarin C was synthesized. For the first time, the structure of open-chain fusarin C was elucidated, and on the basis of these data, the rearrangement product of fusarin C was identified as epi-fusarin C. The results were confirmed by detailed NMR measurements and density functional theory calculations. Furthermore, a new fusarin C like metabolite, which was named dihydrofusarin C, was detected by analysis of the crude extract of fusarin C with high-performance liquid chromatography coupled to UV and Fourier transform mass spectrometry.  相似文献   
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Chemical mass balance (CMB) and principal component analysis (PCA) are used together for source identification and source apportionment in this air pollution modeling study. Source profile sets, each of which contains five source profiles based on ten pollutant species, were generated using a computer program. Another algorithm was implemented to produce ten random data sets, which was composed of 100 simulated measurement results for all of ten pollutant species. Ten source profile sets were selected. Five of them contained sources of dissimilar characteristics, whereas the other five were chosen from those of similar emission profiles. Ten simulated data sets for each source profile set were used in the analyses. PCA was applied to all simulated data sets; a number of principal factors were extracted and interpreted. The identified sources for each data set were used in fitting with CMB analyses, and source contributions were estimated. The performance of PCA–CMB combination was evaluated in the aspect of percent variance explained, percent apportionment, R 2, and χ 2. PCA was able to explain 89.6% to 100% of the variance within the data sets used. Two to five sources were extracted depending on the characteristics of source profile sets used. CMB was found to be successful in the aspect of percent apportionment since 95.4% to 100% of mass concentrations were apportioned. The values of R 2 and χ 2 were found out to range from 0.981 to 1.000 and from 0.000 to 29.947, respectively. Evaluating overall results from the analyses, PCA–CMB combination produced satisfactory results in the aspect of source identification and source apportionment.  相似文献   
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One-day-old SPF chicks were inoculated with the Cux-l strain of chicken infectious anemia virus (CIAV), and the clinical development of disease and its macroscopic and microscopic alterations in the thymus and bone marrow, were observed. Tissue sections of thymus and bone marrow were stained using the streptavidin-biotin peroxidase method and examined under light microscope for evaluation of antigenic intensities in tissues. Those findings were then compared with blood parameters and ELISA results obtained through collected sera during sacrifice procedures. We sought to determine: the localization of viral antigens in thymus and bone marrow tissues after inoculation, the correlation between antigen intensities and hematologic, serologic and histopathologic findings, definitive diagnostic criteria using histopathologic and immunoperoxidase methods, and the reliability of these methods in the diagnosis of CIAV infection. For this purpose, 83, one-day-old SPF chicks were used. The birds were divided into experimental (n = 52) and control (n = 26) groups. A virus dose of TCID50 of 100,000/ml was administered intramuscularly to every bird in the experimental group. Based on the results of this study, we have suggested that clinical examination, along with macroscopic and microscopic evaluation of the thymus and bone marrow, maybe undertaken starting from day 7 post-inoculation (PI). ELISA, might be of value, as it might give consistent results starting from day 14 PI. However, the most reliable results were obtained through examination of thymus and bone marrow sections from infected birds stained by immunoperoxidase technique, as early as day 4 PI.  相似文献   
117.
Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1). Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data) and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application.  相似文献   
118.
This comprehensive overview of block copolymer micelle nanolithography (BCMN) will discuss the synthesis of inorganic nanoparticle arrays by means of micellar diblock copolymer approach and the resulting experimental control of individual structural parameters of the nanopattern, e.g., particle density and particle size. Furthermore, the authors will present a combinational approach of BCMN with conventional fabrication methods, namely, photolithography and electron beam lithography, which combines the advantages of high-resolution micronanopatterning with fast sample processing rates. In addition, the authors will demonstrate how these nanoparticle assemblies can be transferred to polymer substrates with a wide range of elasticity. In the second part of this report the authors will introduce some of the most intriguing applications of BCMN in biology and materials science: The authors will demonstrate how nanoparticle arrays may be used as anchor points to pattern functional proteins with single molecule resolution for studying cellular adhesion and present a technological roadmap to high-performance nanomaterials by highlighting recent applications for biomimetic optics and nanowires.  相似文献   
119.
Objective To determine physiologic levels of tear production in Arabian (AH) and throughbred horses (TH) by using phenol red thread test (PRT). Animals studied The study was performed on 16 AH and 14 TH, ranging from 2.5 to 24 years of age, housed in a stable situated in the Sanliurfa of Turkey. Procedures For the measurement of PRT, the strip was placed under the lower eyelid approximately one‐third the distance from the temporal to nasal canthus and left for 15 s. The length of the wet area was measured in mm and compared among breed, sex, and age groups and between eyes of both sides. Results The mean length of the wet area was in AH and TH were 30.22 ± 0.99 mm ranging from 16 to 41 and 31.00 ± 1.4 mm ranging from 14 to 47, respectively. There were no significant differences in tear production among breed, sex, or age groups. The values measured for left eyes were significantly higher than those for right eyes (P < 0.05). Conclusions Phenol red thread test measurement is easily used, with no pain, and a comfortable method. PRT can be used in equine ophthalmology on a routine basis to the measurement of tear production. These normal PRT values help diagnosis keratoconjunctivitis sicca in horses.  相似文献   
120.
Interactive effects of silicon (Si) and high boron (B) on growth and yield of tomato (Lycopercison esculentum cv. ‘191 F1’) plants were studied. Treatments were: 1) control (B1), normal nutrient solution including 0.5 mg L?1 B (boron), 2) B1 +Si treatment: 0.5 mg L?1 boron plus 2 mM Si, 3) B2 treatment: 3.5 mg L?1 B, 4) B2 +Si treatment: 3.5 mg L?1 B plus 2 mM Si, 5) B3 treatment: 6.5 mg L?1 B, and 6) B3 +Si: 6.5 mg L?1 B plus 2 mM Si. High B reduced dry matter, fruit yield and chlorophyll (Chl) in tomato plants compared to the control treatment, but increased the proline accumulation. Supplementary Si overcame the deleterious effects of high B on plant dry matter, fruit yield and chlorophyll concentrations. High B treatments increased the activities of superoxide dismutase (SOD; EC 1.15.1.1), peroxidase (POD; EC. 1.11.1.7) and polyphenol oxidase (PPO; EC 1.10.3.1). However, supplementary Si in the nutrient solution containing high B reduced SOD and PPO activities in leaves, but POD activity remained unchanged. These data suggest that excess B-induced oxidative stress and alterations in the antioxidant enzymes. Boron (B) concentrations increased in leaves and roots in the elevated B treatment as compared to the control treatment. Concentrations of calcium (Ca) and potassium (K) were significantly lower in the leaves of plants grown at high B than those in the control plants. Supplementing the nutrient solution containing high B with 2 mM Si increased both nutrients in the leaves. These results indicate that supplementary Si can mitigate the adverse effects of high B on fruit yield and whole plant biomass in tomato plants.  相似文献   
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