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41.
Age, growth and maturity data of the freshwater feather back Chitala chitala (Hamilton-Buchanan, 1822) were collected from ten different geographical locations. Out of ten populations, maximum 6+ ages were recorded from four river basins namely river Bhagirathi, Koshi, Saryu and Ganga and the back calculated lengths at 6+ ages ranged from 1033.36–1073.63 mm. In rest of the locations, however, only 3+ age classes were recorded. Specific rate of linear growth (Cl) and specific rate of weight increase (Cw) showed decreases except in two locations. The specific rate of linear growth (Cl) and the specific rate of weight increase (Cw) increased at 3+ age class in the river Bhagirathi. Among other growth parameters, three distinct life stages of C. chitala were observed based on analysis of growth constant data. Analysis of variance (ANOVA) of the back-calculated length data of 10 populations indicated a significant difference (p < 0.05). Out of ten populations studied, six showed significant variation of growth in 1+ age class and two showed significant variation in 2+ to 6+ age classes. Length-weight relationship of the species from all the population was calculated and the coefficient of correlation (r) was at the significant level where the value of ‘b’ was almost 3 for all the locations studied. Male C. chitala attained maturity earlier (2+ age) whereas females matured at age 3+. The percentages of mature individuals also varied between river basins. Based on this study strategies can be proposed for sustainable exploitation of the species from wild populations.  相似文献   
42.
Soil hydrolases and their association with carbohydrates. Active enzymes isolated from soil in the form of carbohydrate-enzyme-complexes could not be separated from each other by DEAE cellulose chromatography. All enzymes measured in this complex were recovered in Chromatographie fractions with different specific activities and variations in carbohydrate contents. There is however, no linear relationship between the quantity of carbohydrates and specific activities of the fractions. The carbohydrate-enzyme-complexes are not glycoproteins, but the enzymes are physically adsorbed on polysaccharides in a non-covalent manner. The essential role of this carbohydrate is to protect the enzyme systems against denaturation or proteolysis, thus ensuring their stability in soil.  相似文献   
43.
The present study was undertaken to characterize the ultrastructural morphology of the blood cells of commonly reared chickens in the state of Mizoram, India under backyard poultry farming. For this study, 2 ml of whole blood was aseptically collected from the wings veins of 12 chickens of three different breeds namely the Zoar, Aseel and Rhode Island Red and processed for ultrastructural imaging under standard protocols. Under scanning electron microscopy (SEM) the matured erythrocytes of Zoar, Aseel and Rhode Island Red appeared elliptical in shape while the leukocytes and thrombocytes appeared round in shape with variable surface modifications. Under transmission electron microscopy (TEM) the granules of the heterophils of Zoar, Aseel and Rhode Island Red appeared predominantly fusiform in shape, the granules of the eosinophils appeared round in shape and that of the basophils appeared pleomorphic in shape. The cytoplasm of the monocytes, medium-to-large lymphocytes and thrombocytes of Zoar, Aseel and Rhode Island Red under TEM appeared to be vacuolated and granular while that of the small lymphocytes appeared to be granular but non-vacuolated. The study concluded that the ultrastructural characteristics of the blood cells of the three breeds of chicken studied were almost similar to the blood cells of other birds reported earlier.  相似文献   
44.
Zusammenfassung Fluoreszierende Pseudomonaden, die sich als Antagonistenin vitro gegenüberRhizoctonia solani undPythium aphanidermatum erwiesen haben, wurden an Gurken und Bohnen auf Antagonismusin vivo untersucht. Die Effizienz der Antagonisten in Auflaufversuchen gegenüberR. solani war niedriger als beiP. aphanidermatum. Die besten Isolate konnten in mitR. solani verseuchter Erde Auflaufraten von 30–40% erzielen, gegenüberP. aphanidermatum dagegen 40–60%. Die Wirkung der Antagonisten zur Verhütung von Spätinfektionen der Pflanzen war deutlich besser. So konnten 16 Isolate eine Schädigung durchR. solani an Bohnen zwischen 90 und 100% reduzieren. An Gurken konnten 12 Isolate eine Schädigung durchP. aphanidermatum auf 70–80% reduzieren.
Fluorescent pseudomonads, which showed antagonism in vitro against Rhizoctonia solani and Pythium aphanidermatum, were investigated for antagonism in vivo using bean and cucumber. The efficiency of the antagonists in germination tests against Rhizoctonia solani was lower than against Pythium aphanidermatum. In soil infected with Rhizoctonia solani the germination rates of the seeds remained between 30 and 40%, whereas against Phytium aphanidermatum some Pseudomonas-strains caused germination rates of 40–60%. The preventive effect of the antagonists against fungal infection after the germination was better. 16 isolates reduced the damage caused by Rhizoctonia solani to bean between 90 and 100%. Damage caused by Pythium aphanidermatum to cucumber was reduced by 12 antagonists between 70 and 80%.


Mit 4 Abbildungen  相似文献   
45.
Zusammenfassung In einem Huhn wurden polyklonale Antikörper gegen TMV produziert. Da, um das immunologische Gedächtnis optimal auszunutzen, die Spanne zwischen erster und zweiter Immunisierung größer sein sollte als dies üblicherweise bei phytopathogenen Viren gehandhabt wird, erfolgte die zweite Immunisierung 10 Wochen nach der ersten. Bei diesem langen zeitlichen Abstand konnte nach der zweiten Immunisierung bei den Antikörpern aus dem Eidotter ein Titter von 80000 erzielt werden, nach der dritten Immunisierung stieg der Titer auf 160000. Die Antikörper, die man aus dem Blutserum gewann (Titer: 40000), konnte man auch erfolgreich im ELISA einsetzen.
Raising polyclonal antibodies against TMV in a hen utilizing the immunological memory
Polyclonal antibodies were raised against TMV in a hen. According to the immunological theory that in order to get a good immunological memory the time interval between the first and the second immunization should be larger than mostly practised in the case of plant viruses, the second immunization was undertaken 10 weeks after the first. Using this long interval a titer of 80000 could be achieved for antibodies from egg yolk after the second immunization. After the third immunization the titer increased up to 160000. The antibodies from the blood serum (titer: 40000) could also be used successfully for the ELISA.


Mit einer Abbildung und einer Tabelle  相似文献   
46.
Sperm motility is considered as one of the most important traits for successful fertilization, but the motility of an ejaculated sperm decreases with time when stored as liquid. It is reported that seminal plasma serves as a nutrient rich medium for sperm and plays an important role in sperm motility and its fertilization ability. Several studies have reported that imidazole dipeptides such as anserine and carnosine affect sperm motility and its fertilization ability in mammals. In this study, we report the presence of anserine and carnosine in the male reproductive tract of the Japanese quail. Abundant levels of anserine (44.46 µM) and carnosine (41.75 µM) were detected in the testicular fluid and seminal plasma respectively using the amino acid analyzer; however, seminal plasma solely contained carnosine. When the ejaculates were incubated with anserine or carnosine, we found that both the dipeptides improve sperm motility parameters such as straight line velocity, curvilinear velocity, average path velocity and amplitude of lateral head displacement after in vitro sperm storage at 15°C. These results indicate that imidazole dipeptides are present in the male reproductive tract and may improve sperm quality during in vitro sperm storage in the liquid states.  相似文献   
47.
In einem Huhn wurden polyklonale Antikörper gegen TMV produziert. Da, um das immunologische Gedächtnis optimal auszunutzen, die Spanne zwischen erster und zweiter Immunisierung größer sein sollte als dies üblicherweise bei phytopathogenen Viren gehandhabt wird, erfolgte die zweite Immunisierung 10 Wochen nach der ersten. Bei diesem langen zeitlichen Abstand konnte nach der zweiten Immunisierung bei den Antikörpern aus dem Eidotter ein Titter von 80000 erzielt werden, nach der dritten Immunisierung stieg der Titer auf 160000. Die Antikörper, die man aus dem Blutserum gewann (Titer: 40000), konnte man auch erfolgreich im ELISA einsetzen.Polyclonal antibodies were raised against TMV in a hen. According to the immunological theory that in order to get a good immunological memory the time interval between the first and the second immunization should be larger than mostly practised in the case of plant viruses, the second immunization was undertaken 10 weeks after the first. Using this long interval a titer of 80000 could be achieved for antibodies from egg yolk after the second immunization. After the third immunization the titer increased up to 160000. The antibodies from the blood serum (titer: 40000) could also be used successfully for the ELISA.
Mit einer Abbildung und einer Tabelle  相似文献   
48.
Postnatal persistence of foetal haemoglobin in yaks   总被引:2,自引:0,他引:2  
  相似文献   
49.
The effect of sublethal concentrations, 0.00141% (LC20), 0.00251% (LC30), and 0.0036% (LC40) of a dispersible formulation of an acylurea insect growth regulator, flufenoxuron (Cascade) on certain biochemical parameters in the larvae of Tribolium castaneum was investigated. When neonates were fed on diet treated with sublethal concentrations for 24 h, it was observed that at all concentrations tested, there was a significant reduction in chitin content on the 15th day of development. Total soluble protein content at LC20 and LC30 decreased with increasing age of the larvae. At LC20 and LC40 concentrations there was a progressive increase in the protein: chitin ratio as a function of increase in age of the larvae. SDS-PAGE analysis of the larval tissue extracts indicated gross quantitative changes in some of the protein bands (MW 50-97 kDa). Western blot analysis revealed significant increase in the level of HSP70 in the extracts of larvae fed on LC30 treated diet, on the 7th and 10th day of development in the decreasing order. Conversely, a significant decrease in the hyper-phosphorylated form of p34cdc2 kinase due to flufenoxuron treatment indicating modulation of cell cycle regulation was observed. Thus, sublethal concentrations of flufenoxuron alter expression of developmentally regulated proteins, HSP70 and p34cdc2 and chitin formation in a stage-specific manner thereby resulting developmental abnormalities in T. castaneum.  相似文献   
50.
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