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121.
S.-J. Lee    C.-S. Oh    J.-P. Suh    S. R. McCouch  S.-N. Ahn 《Plant Breeding》2005,124(3):209-219
Asian cultivated rice was domesticated from the wild rice, Oryza rufipogon and throughout the domestication process, a wide range of morphological and physiological changes altered the ancestral form. This study was conducted to identify the genetic basis of changes associated with the domestication process. An recombinant Inbred line (RIL) population consisting of 120 lines was developed from a cross between the Juponica cultivar.‘Hwayeongbyeo’and a presumed wild progenitor. O. rufipogon Griff. Acc.01944. The population was genotyped with 124 simple sequence length repeat (SSR) markers, providing an average interval size of 15 cM, and also evaluated for 20 traits related to domestication and agricultural performance. A total of 63 quantitative trait locus (QTLs) and one locus associated with qualitative variation for pericarp coloration were identified using single point and composite interval analysis. The number of QTLs per trait ranged from one to seven. Phenotypic variation associated with each QTL ranged from 3.7 to 40.4%. with an average of 15.3%. The results indicated that most domestication‐related traits clustered in chromosomal blocks, and the positions of many of these clusters were consistent with those reported in previous studies and with skewed segregation ratios in these BC1,F7 RILs. For 13 (20.6%) of the QTLs identified in this study. the O. rufipogan ‐derived allele contributed a desirable agronomic effect despite the overall undesirable characteristics of the wild phenotype. Favourable alleles from O. rufipogan were detected for panicle length, spikelets per panicle, days to heading and leaf discoloration associated with cold stress. When compared with previous studies involving interspecific crosses, it can be concluded that O. rufipogon is useful as a source of valuable alleles for rice improvement and that many of the introgressed regions contain genes that have a favourable impact on phenotype in different genetic backgrounds and different environments.  相似文献   
122.
Two new cell cultures from flounder, Paralichthys olivaceus (Temminck & Schlegel), flounder fin (FFN) cells from fin tissue and flounder spleen (FSP) cells from spleen tissue, were established and characterized. The cells multiplied well in Eagle's minimum essential medium, supplemented with 10% foetal bovine serum, and have been subcultured more than 100 times, becoming continuous cell lines. Modal diploid chromosome number of FFN and FSP cells was 64 and 62, respectively. Polymerase chain reaction products were obtained from FFN and FSP cells with primer sets ofmicrosatellite markers of flounder. Optimal growth temperature was 20 degrees C and consisted of epithelioid cells. FFN and FSP cells showed cytopathic effects after inoculation of infectious pancreatic necrosis virus, marine birnavirus, chum salmon virus, infectious haematopoietic necrosis virus, spring viraemia of carp virus and hirame rhabdovirus. Thus these new cell lines may be useful for studying a wide range of fish viruses.  相似文献   
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124.
The aim of this study was to determine the immunoreactivity of normal small bronchial, bronchiolar, respiratory bronchiolar, and interalveolar epithelium using antibodies to six mucins: MUC1, MUC2, MUC4, MUC5AC, MUC5B, and MUC6. The large, gel-forming secreted mucins MUC2, MUC5AC, and MUC5B were widely expressed in the lower respiratory tract. The results of this study demonstrate that these secreted mucins form a gel to cover and protect the mucosal surface in the lower respiratory tract of pigs.  相似文献   
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126.
Extra‐firm actors have been acknowledged as vital to the success of green energy industries. This article deploys the firm network perspective to deliver a first of its kind analysis of specific extra‐firm actor impacts on firm performance in Korea's solar photovoltaic industry. Results are based on quantitative analyses of data from 60 firm respondents and augmented by interviews with eight government officials. Three research questions capture and compare firm and government actor perceptions pertaining to extra‐firm actor influences at the national, regional, and extra‐local scales, inclusive of place–place competition and cooperation. Results indicate that firms differ in perceptions related to the impact of 18 national level government institutes, R&D centers, associations, and academic societies on their success, and that perceptions vary by level of technology concerning a plethora of other related extra‐firm actor and support infrastructure impacts. A comparative perspective is presented based on government informant interviews.  相似文献   
127.
Diagnosis of acute pancreatitis in dogs remains a significant challenge despite the development of advanced diagnostic methodologies. Visual inspection and pancreas biopsy using laparoscopy are generally considered to be procedures free of complications when conducted on healthy animals. However, the usefulness of laparoscopy for diagnosing acute pancreatitis has not been assessed. In the present study, the efficacy of laparoscopy for diagnosing acute pancreatitis in dogs was evaluated in animals with experimentally induced acute pancreatitis. Gross appearance of the pancreatic area was examined by laparoscopy to survey for the presence of edema, adhesions, effusion, pseudocysts, hemorrhage, and fat necrosis. Laparoscopic biopsy was performed and the histopathologic results were compared to those of pancreatic samples obtained during necropsy. The correlation between laparoscopy and histopathologic findings of the pancreas was evaluated. The presence of adhesions, effusion, and hemorrhage in the pancreatic area observed by laparoscopy significantly correlated with the histopathologic results (p < 0.05). There was no significant relationship between the histopathologic and laparoscopic biopsy findings. Results of this study suggested that laparoscopic evaluation of gross lesions has clinical significance although the laparoscopic biopsy technique has some limitations. This method combined with additional diagnostic tools can be effective for diagnosing acute pancreatitis in dogs.  相似文献   
128.
Antibiotics have traditionally been used for growth promotion in the pork industry; however, their use in animal feed has recently been limited because of human health concerns. The intestinal microbiota plays an important role in mediating many physiological functions such as digestion and animal growth. It was hypothesized that use of antibiotics as growth promotants and subsequent variations in intestinal microbiota induce significant changes in the intestinal glycoconjugate composition, which ultimately affects animal growth and disease susceptibility. The aim of this study was to characterize the lectin binding profiles of the ileum of weanling pigs in response to the absence of intestinal microbiota and to the use of the antibiotic chlortetracycline as growth promotant. Eighteen half-sib piglets obtained by cesarean section were divided into 3 treatment groups (n = 6) and maintained as control, antibiotic-fed, and gnotobiotic piglets until 5 wk of age. The glycoconjugate composition of the ileal tissues was examined by lectin histochemistry. Lycopersicon esculentum lectin, Jacalin, Pisum sativum agglutinin, Lens culinaris agglutinin (LCA), and Sambucus nigra lectin showed significant differences (P < 0.05) in binding intensities on the dome and villous epithelium between the treatment groups. Griffonia simplicifolia lectin I, Glycine maxi agglutinin, and Arachis hypogea agglutinin exhibited differences (P < 0.05) between treatment groups in lectin binding on goblet cells. Triticum vulgaris agglutinin, Pisum sativum agglutinin, and LCA showed significant differences (P < 0.05) in binding intensities on dome, corona, and follicular regions of the ileum among treatment groups of animals. Overall, ileal tissues from gnotobiotic piglets expressed significantly weaker (P < 0.05) lectin binding for many lectins compared with control and antibiotic groups. This suggests that the intestinal microbiota plays an important role in the expression of sugar moieties in the intestine. Lectins LCA, Phaseolus vulgaris Leucoagglutinin, and Maackia amurensis lectin II showed significant differences (P < 0.05) in lectin bindings between control and antibiotic-fed piglets. This indicates that chlortetracycline as a growth promotant induces biologically relevant changes in the lectin binding profile of the ileum. These findings will help in further understanding the role of the gut microbiota and the mechanisms of action of antibiotics as growth promotants in pigs.  相似文献   
129.
Trans epidermal water loss (TEWL), skin hydration status and pH were determined in 14 skin regions of five healthy male Beagle dogs (2–4 years) both before and after anaesthesia. Trans epidermal water loss was highest for the footpad and head and lowest for the inguinal region. Skin hydration status was higher in the ear but did not vary significantly in other regions. Skin pH was usually alkaline with the highest values on the lower back and tail. Following anaesthesia, TEWL and skin hydration were significantly lower on the head, upper back and footpad, and upper back and elbow respectively, while skin pH was unaffected by this procedure. While measurement of pH would seem to be valid anywhere on the body in anaesthetized dogs, regional factors should be considered when interpreting TEWL and skin hydration values and when treating regional skin diseases in veterinary practice.  相似文献   
130.
BACKGROUND: Microbial secondary metabolites are a rich source of antifungal agents and have merit as alternatives to synthetic fungicides. To develop disease control agents against powdery mildew, the lipopeptide antibiotic neopeptins were identified from the culture broth of a Streptomyces sp., and in vivo control efficacy of the compounds was evaluated on cucumber plants under glasshouse conditions. RESULTS: The Streptomyces sp. KNF2047 antagonistic against powdery mildew development in cucumber plants was isolated from a soil sample. Antifungal compounds were purified from the culture broth and identified as neopeptin A and B. In vitro microtitre assays revealed the inhibitory activities of the compounds in the range 128-512 microg mL(-1) against the mycelial growth of Alternaria mali, Botrytis cinerea, Cladosporium cucumerinum, Colletotrichum lagenarium, Didimella bryoniae and Magnaporthe grisea. Although neither compound showed remarkable in vitro antifungal activity against other plant pathogenic fungi, a mixture of neopeptins (484 mg of neopeptin A and 290 mg of neopeptin B per gram of partially purified powder) showed potent protective and curative activity against cucumber powdery mildew in vivo. The disease control activity of the neopeptins at a concentration of 2.4 mg L(-1) was 92.1%, which was similar to that of the commercial fungicide fenarimol (89.3% at 63 mg L(-1)) and that of the commercial biocontrol agent Actinovate (67.4% at 2 x 10(7) cfu L(-1)). CONCLUSION: Neopeptin mixtures isolated from Streptomyces sp. KNF2047 showed potent disease control activity against powdery mildew development on cucumber plants. .  相似文献   
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