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61.
Genomic selection has been adopted in many plant breeding programmes. In this paper, we cover some aspects of information necessary before starting genomic selection. Spring oat and barley breeding data sets from commercial breeding programmes were studied using single, multitrait and trait-assisted models for predicting grain yield. Heritabilities were higher when estimated using multitrait models compared to single-trait models. However, no corresponding increase in prediction accuracy was observed in a cross-validation scenario. On the other hand, forward prediction showed a slight, but not significant, increase in accuracy of genomic estimated breeding values for breeding cohorts when a multitrait model was applied. When a correlated trait was used in a trait-assisted model, on average the accuracies increased by 9%–14% for oat and by 11%–28% for barley compared with a single-trait model. Overall, accuracies in forward validation varied between breeding cohorts and years for grain yield. Forward prediction accuracies for multiple cohorts and multiple years’ data are reported for oat for the first time.  相似文献   
62.
Yellow mosaic disease, caused by wheat yellow mosaic virus (WYMV), is one of the most serious diseases of winter wheat in Japan and China. A single major QTL for WYMV resistance in the Japanese wheat variety 'Yumechikara', designated Q.Ymym, has been mapped on a 43.6 cM linkage block between the two markers Xcfd233 and Xgwm349 on chromosome 2D. We were able to obtain two recombinants within the block, which facilitated reducing the size of the linkage block. The pseudomolecule sequence of 'Chinese Spring' (CS) indicated that the original Q.Ymym region of 43.6 cM corresponded to 68.5 Mb and the narrowed Q.Ymym region represents a size of 27.3 Mb. The sequence features of the Q.Ymym region were unique in comparison with CS sequences, which may have led to the low recombination rate within the block. The Q.Ymym haplotype block was detected in other WYMV-resistant varieties but not in the susceptible varieties used in this study. The unique sequence structure of the Q.Ymym region allowed the development of co-dominant markers for use in marker-assisted selection.  相似文献   
63.
A cholesterol-free diet containing dried powder of Jew's mellow leaves, persimmon leaves or sweet potato leaves respectively at 5% level as dietary fiber was fed to male Sprague-Dawley rats for about one month. The experiment was conducted twice except for sweet potato leaves. In the groups fed the diet mixed with powders of any of the three different dried green leaves, the hepatic cholesterol concentration significantly decreased. Such lowering was not observed in serum cholesterol concentration compared with the control (cellulose) group. A significant increase in fecal weight was observed in all the groups fed the green leaf samples. All the dried green leaves increased fecal excretion of bile acids per gram or per day compared with the control group in both experiments, but only the dried Jew's mellow leaves showed an increased excretion of neutral sterols. These results suggest that lowering of hepatic cholesterol by powdered green leaves is not necessarily due to the same factor, but to the increased fecal excretion of bile acids due to inhibited enterohepatic circulation in animals given these samples.  相似文献   
64.
An 11-year-old thoroughbred gelding was euthanatized because of right nasal cavity tumor. The tumor consisted of round to oval cells with a scanty cytoplasm and hyperchromatic nuclei. Homer-Wright rosettes and pseudorosettes, as well as microcysts were seen. Neoplastic cells were immunoreactive to vimentin, S-100 protein, and neuron-specific enolase, glial fibrillary acidic protein and microtube-associated protein in varying degrees, indicating neurogenic nature. Based on these findings, this tumor was diagnosed as an olfactory neuroblastoma. Since this type is an uncommon tumor showing histological variety, the nature is discussed.  相似文献   
65.
The composition of tropomyosin (TPM) and myosin heavy chain (MyHC) isoforms was analyzed in 10 physiologically different bovine muscles ( masseter , diaphragm, tongue, semispinalis, pectoralis profundus , biceps femoris, psoas major , semimembranosus, longissimus thoracis and semitendinosus ) to clarify the relationships between TPM and MyHC isoforms in different muscle fiber types. The content of TPM1 and TPM3 was different in muscles according to their function in muscle contraction, although the content of TPM2 was constantly about 50% of the total TPM in all muscles. The content of TPM1 was higher in semimembranosus , longissimus thoracis and semitendinosus, while that of TPM3 was higher in masseter and diaphragm. The high positive correlation between MyHC-slow content and TPM3 content ( r  = 0.92) suggested a coexpression of TPM3 and MyHC-slow isoforms in a muscle fiber. MyHC-slow and TPM3 were expressed at the same level in masseter and diaphragm, whereas there was more TPM3 than MyHC-slow in tongue and semispinalis , so it appears that the excess TPM3 in tongue and semispinalis is expressed with other MyHC isoforms. MyHC-2a was the only fast type isoform expressed in tongue and semispinalis . Therefore, the excess TPM3 was composed of myofibrils with MyHC-2a. The results suggested that a fiber expressing MyHC-2a would be regulated delicately by changing the TPM isoform types.  相似文献   
66.
Improving broad specificity hapten recognition with protein engineering   总被引:1,自引:0,他引:1  
Sulfa antibiotics (sulfonamides) are derivatives of p-aminobenzenesulfonamide that are widely used in veterinary medicine. Foods derived from treated animals may be contaminated with these drugs. However, current immunobased sulfonamide detection methods are unfit for screening of products because they are either too insensitive or specific for a few compounds only. An immunoassay capable of detecting all sulfas in a single reaction would be ideal for screening. For development of a binder capable of binding all sulfas, a protein engineering approach was chosen and the properties of monoclonal antibody 27G3 were improved with mutagenesis followed by selection with phage display. Several different mutant antibodies were isolated. The cross-reaction profile of the best mutant antibody was significantly improved over that of the wild-type antibody: it was capable of binding 9 of the tested 13 sulfonamides within a narrow concentration range and also bound the rest of the sulfas, albeit within a wider concentration range.  相似文献   
67.
Bovine viral diarrhea virus (BVDV) field isolates show genetic and antigenic diversity. At least 14 subgenotypes of BVDV-1 and 4 of BVDV-2 have been identified in Artiodactyla worldwide. Of these, 6 subgenotypes of BVDV-1 and 1 of BVDV-2 have been isolated in Japan. Previously, we reported that each subgenotype virus expresses different antigenic characteristics. Here we investigated the reactivity of neutralizing antibodies against representative strains of Japanese BVDV subgenotypes using sera from 266 beef cattle to estimate the prevalence of this epidemic virus among cattle in Japan. Antibody titers at concentrations at least 4-fold higher than antibodies against other subgenotype viruses were considered subgenotype specific. Subgenotype-specific antibodies were detected from 117 (80.7%) of 145 sera samples (69.7% against BVDV-1a, 1.4% against BVDV-1b, 8.3% against BVDV-1c, and 1.4% against BVDV-2a). The results suggest that neutralization tests are useful in estimating currently epidemic subgenotypes of BVDV in the field.  相似文献   
68.
The development of precision farming needs methods for automatic identification of individual plant species. We have earlier shown that chlorophyll fluorescence induction curves can be reliably used for automatical identification of plants (Tyystjärvi et al., 1999). In the present study we show that a high accuracy of recognition can be obtained even if the teaching set for pattern recognition is collected several weeks before identifying a test batch of plants. It is also shown that very simple fluorescence traces can be used for the identification, and that dark pre-incubation of the plants can be shortened to a few seconds without seriously compromising the power of the method. The method is even more powerful if the aim is only to distinguish one crop species from weeds. The data shown here suggest that the fluorescence fingerprint can be developed to a method of practical importance for precision farming.  相似文献   
69.
Endophytic bacteria carrying out dinitrogen (N2) fixation and indole acetic acid (IAA) synthesis were firstly identified in C. alismatifolia, a globally important flower crop. Their potential as growth promoters to stimulate the rapid growth of host plant was also examined. It will be beneficial to reduce the propagation period of tissue culture plantlets, and also utilize as a biofertilizer for rhizome production in the field. Seven endophytic bacteria were isolated from the leaf, four isolates from the leaf base, and two from the rhizome. ECS203, a gram-negative bacterium with a round shape, showed the highest N2 fixation at 4.2 nmol C2H4/106 cells/hr, and ECS202 showed the highest IAA synthesis at 296 μL μg ? 1 protein. Three selected isolates of N2-fixing and IAA synthesizing endophytic bacteria, i.e., ECS202, ECS203, and ECS204, isolated from the leaf base, were used to reinoculate Curcuma plantlets derived from tissue culture. Then, plants were grown in sterilized sand for 2 months and weekly supplied with N-free nutrient solution. Plant growth, colonization, nitrogen fixation, and IAA synthesis were measured at two months after planting. The inoculated plants clearly showed a better performance of plant growth and yield in terms of the plant height, plant weight, leaf area, and diameter of new rhizomes compared with uninoculated plants. The chlorophyll content and N concentration of leaves and roots also increased in inoculated plants. Endophytic bacteria from inoculated plants colonized the roots, rhizome, and leaf base. Partial sequence analysis using 16S rDNA indicated that the isolate ECS202 corresponded to Sphingomonas pseudosanguinis (99.2% similarity over 1,371 bp), ECS203 to Bacillus drentensis (99.4% similarity over 1,450 bp) and ECS204 to Bacillus methylotrophicus (99.9% similarity over 13,06 bp).  相似文献   
70.
ObjectiveTo study the effects of oromucosal detomidine gel administered sublingually to calves prior to disbudding, and to compare its efficacy with intravenously (IV) administered detomidine.Study designRandomised, prospective clinical study.AnimalsTwenty dairy calves aged 12.4 ± 4.4days (mean ± SD), weight 50.5 ± 9.0 kg.MethodsDetomidine at 80 μg kg?1 was administered to ten calves sublingually (GEL) and at 30 μg kg?1 to ten control calves IV (V. jugularis). Meloxicam (0.5 mg kg?1) and local anaesthetic (lidocaine 3 mg kg?1) were administered before heat cauterization of horn buds. Heart rate (HR), body temperature and clinical sedation were monitored over 240 minutes. Blood was collected from the V. cephalica during the same period for drug concentration analysis. Pharmacokinetic variables were calculated from the plasma detomidine concentration-time data using non-compartmental methods. Statistical analyses compared routes of administration by Student’s t-test and linear mixed models as relevant.ResultsThe maximum plasma detomidine concentration after GEL was 2.1 ± 1.2 ng mL?1 (mean ±SD) and the time of maximum concentration was 66.0 ± 36.9 minutes. The bioavailability of detomidine was approximately 34% with GEL. Similar sedation scores were reached in both groups after administration of detomidine, but maximal sedation was reached earlier in the IV group (10 minutes) than in the GEL group (40 minutes). HR was lower after IV than GEL from 5 to 10 minutes after administration. All animals were adequately sedated, and we were able to administer local anaesthetic without resistance to all of the calves before disbudding.Conclusions and clinical relevanceOromucosally administered detomidine is an effective sedative agent for calves prior to disbudding.  相似文献   
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