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131.
The sudden emergence of severe acute respiratory syndrome (SARS) at the end of 2002 resulted in 774 reported deaths from more than 8000 cases worldwide. As no effective vaccines or antiviral agents are available, the most effective measure to prevent the expansion of a SARS epidemic is the rapid diagnosis and isolation of SARS patients. To establish specific diagnostic methods, we generated nine clones of monoclonal antibodies to nucleocapsid protein (NP) of SARS-coronavirus (SARS-CoV). On immunofluorescent antibody assay and Western blotting analysis, none of the monoclonal antibodies showed cross-reactivity to authentic and recombinant NPs of human coronavirus (HCoV) 229E strain. To determine the region on the NP molecule where the monoclonal antibodies bind, we generated four truncated recombinant NPs and analyzed the reactivity between monoclonal antibodies and truncated NPs. Two monoclonal antibodies reacted with a truncated NP covering from amino acid residues 111 to 230, and seven reacted with another truncated NP covering from amino acid residues 221 to 340. Epitope mapping analysis indicated that monoclonal antibody SN5-25 recognized the amino acid sequence Q(245)TVTKK(250) On SARS-NP. Within the epitope, Q245, T246, V247, K249, and K250 appeared to form an essential motif for monoclonal antibody SN5-25 to bind. The information about binding sites and epitopes of monoclonal antibodies may be useful for the development of new diagnostic methods for SARS and for analyzing the function of N protein of SARS-CoV.  相似文献   
132.
Over a period of 20 years, a total of 207 Mannheimia haemolytica samples were isolated from calves affected with pneumonic pasteurellosis and serotyped by the indirect haemagglutination test. Serotypes A1 (102 isolates), A2 (47 isolates) and A6 (42 isolates) were most common; in addition, 16 isolates were serotypes A7, A13, A14 or untypable. The relative prevalence of serotype A6 has increased recently in Japan, as has been reported from other countries. The results of this study provide useful information towards the design of efficient vaccines for the prevention of M. haemolytica infection in Japan.  相似文献   
133.
Adenovirus (Ad) vectors are widely used in cancer gene therapies. However, compared to human patients, relatively limited information is available on gene transduction efficiency or cell-specific cytotoxicity in canine tumor cells transduced with Ad vectors. Since epidermal growth factor receptor (EGFR) is highly expressed on canine breast tumor cells, we sought to develop an Ad vector based on the RGD fiber-mutant adenovirus vector (AdRGD) that expresses canine caspase 3 under the control of EGFR promoter. The aims of this study were to achieve high transduction efficiency with transgene expression restricted to canine breast tumor cells. Using EGFR promoter-driven AdRGD, we were able to restrict transgene expression to canine breast tumor cells with no evidence of expression in normal cells. Canine breast tumor cells transduced with EGFR promoter-driven AdRGD carrying canine caspase 3 gene showed cytotoxic activity. We constructed a second AdRGD vector that expressed oxygen-dependent degradation (ODD)-caspase 3 under the control of the EGFR promoter; the fusion protein contains a core part of the ODD domain of hypoxia inducible factor-1 alpha (HIF-1α) fused to caspase 3. Transduction of canine breast tumor cells with EGFR promoter-driven AdRGD expressing ODD-caspase 3 induced a higher rate of cell death under hypoxic conditions compared with under normoxia. The results indicate that the EGFR promoter-driven AdRGD vectors will be of value for tumor-specific transgene expression and safe cancer gene therapy in dogs.  相似文献   
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135.
The heartwood and sapwood characteristics of 11 Amazonian trees were investigated. Whereas 7 of the specimens had densities greater than 0.7 g/cm3, the heartwood density of ipê amarelo (Tabebuia serratifolia), maçaranduba (Manilkara huberi), cumaru-ferro (Dipteryx odorata), and guarita (Astronium lecointei) exceeded 1.0 g/cm3. Jatobá contained small amounts of Klason lignin and α-cellulose, and large amounts of holocellulose and alkali extract, suggesting that it has a high polysaccharide content that can be dissolved in an alkaline medium. The difference in the syringyl/guaiacyl (S/G) ratios of the samples before and after alkali extraction suggests that alkali extracts contain syringyl-type polyphenols. In all of the samples, the heart-wood methanol extracts were larger in volume than the sapwood methanol extracts, and the sapwood alkali extracts were larger in volume than the heartwood alkali extracts. The antioxidant activities of the methanol and alkali extracts were assayed by measuring the levels of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and super oxide dismutase (SOD)-like activity, respectively. The heart-wood methanol extract of jatobá (Hymenaea courbaril) exhibited the highest level of activity (EC50 = 44 mg/l), which exceeded that of α-tocopherol (EC50 = 48 mg/l), and the heartwood alkali extracts of jatobá and ipê amarelo had high SOD-like activity comparable with red wine.  相似文献   
136.
Three near-isogenic lines (NILs) of Oryza sativa subsp. indica cv. IR64 (Dro1-NIL, Sta1-NIL, Dro1+Sta1-NIL) with DEEPER ROOTING 1 (DRO1), a novel gene for steeper root growth angle, and/or with Stele Transversal Area 1 (Sta1), a QTL for wider stele area, were tested under flooded lowland (FL), alternate wetting and drying lowland (AWD), and rainfed upland (UP) conditions in 2013 and 2014 to compare the effects of DRO1 and Sta1 on yield across different water management regimes. Genotypic variation and water management effects were significant for grain yield, aboveground biomass, and harvest index, as well as their interactions with year, but no significant genotype × water interaction was detected. Dro1-NIL had 14% higher yield than that of IR64 across the three water conditions due to higher harvest index, aboveground biomass, leaf area index, and number of grains. Sta1 tended to reduce the carbon isotope composition (δ13C), leading to a higher harvest index of Sta1-NIL than that of IR64, but grain yield was not increased. Dro1+Sta1-NIL had the highest fraction of intercepted radiation, cumulative radiation interception, and panicle number, with a small but insignificant yield improvement over IR64, but the combination of DRO1 and Sta1 did not surpass the increment from the effects of DRO1 alone. AWD in the more rainy year 2014 attained both higher water productivity and higher biomass, with significant water by year interaction for water productivity. Genotypic variation in water productivity was related with higher leaf area index and fraction interception, with Dro1-NIL larger than in IR64 and Sta1-NIL.  相似文献   
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138.
In the Japanese macaque, semen has been collected by electro-ejaculation (EE), using the higher voltage stimuli compared to other species including genus Macaca. Semen coagulates immediately after ejaculation, which makes difficult to produce high-quality semen for artificial insemination. Recently, semen collection using urethral catheterization (UC) has been reported in carnivore and this technique may allow semen collection without coagulation in a less invasive manner. Further, the temporal preservation temperature and cooling rate of semen during cryopreservation affect post thawing sperm quality. In this study, to improve semen quality and quantity, as well as the animal welfare, semen collection was performed by EE with high (5–15 V) or low (3–6 V) voltage, UC and a combination of the two (EE-UC). It has been suggested that a high voltage is necessary for semen collection, but 10 V stimulation was effective enough and 15 V is for additional sperm collection. Also, liquid semen was collected by EE-UC and this could increase the total number of sperm. Further, to improve the post thawing sperm motility, semen was kept at four temperatures (4, 15, 25 and 37°C) for 60 min, and processed with two cooling procedures (slow cooling before second dilution and fast cooling after second dilution). Holding semen at 25°C and fast cooling after the second dilution maintained progressive motile sperm rate. The present results will contribute to the improvement of semen collection and animal welfare of Japanese macaques.  相似文献   
139.
Interspecies/intergeneric mitochondrial heteroplasmy can occur in interspecies/intergeneric hybrid embryos or following nuclear transfer. In the present study, intergeneric buffalo (Bubalus bubalis) mitochondria (WB-mt) or interspecies murine (Mus spretus) mitochondria (M-mt) were injected into bovine (Bos taurus) oocytes, and the subsequent embryonic development was characterized. Fibroblast mitochondria (WB-mt or M-mt) were microinjected into in vitro matured bovine oocytes followed by oocyte activation by a combination of electrical stimulation and 6-dimethylaminopurine treatment. After seven days of culture, embryo development was evaluated. The copy number of specific mtDNA populations (introduced and native mtDNA) from heteroplasmic oocytes was estimated using real-time PCR. The results illustrated that oocytes injected with either WB-mt or M-mt can develop to the blastocyst stage (20.6% and 19.6%). Cleavage division rates and development to the morula stage in oocytes injected with WB-mt were lower (76.2% and 45.9%, respectively) in comparison with uninjected oocytes (89.2% and 59.1%, respectively) (P<0.05). However, no differences were found in comparing M-mt injected oocytes and controls (P>0.05). An increase in bovine mtDNA copy number was observed at the expanded blastocyst stage of injected embryos (P<0.01), while the number of injected mtDNA was stable throughout development. This study demonstrates that interspecies/intergeneric mitochondrial injected bovine oocytes have the ability to develop to the blastocyst stage after parthenogenetic activation and that injected mtDNA was neither selectively destroyed nor enhanced through development. Moreover, injected intergeneric mitochondria had a demonstrated influence on bovine parthenogenetic development and mtDNA replication.  相似文献   
140.
The aim of this study was to analyse a florfenicol-resistant Mannheimia haemolytica isolated from a calf to determine the genetic basis of its florfenicol-resistance. The antimicrobial susceptibility and plasmid content of the isolate were determined. A florfenicol resistant plasmid carrying the floR gene was identified by PCR and transformed into Escherichia coli JM109 and HB101 strains. The plasmid was then mapped and sequenced completely. The isolate was resistant to chloramphenicol, florfenicol, oxytetracycline, kanamycin, dihydrostreptomycin, nalidixic acid, ampicillin, and amoxicillin; it carried a floR plasmid of 7.7kb, designated pMH1405. The mobilisation and replication genes of pMH1405 showed extensive similarity to the 5.1-kb pDN1 plasmid from Dichelobacter nodosus and the 10.8-kb pCCK381 plasmid from Pasteurella multocida. An adjacent 2.4-kb segment was highly homologous to the TnfloR region of the E. coli BN10660 plasmid. A plasmid-mediated floR gene was responsible for florfenicol resistance in the bovine respiratory tract pathogen M. haemolytica. The pMH1405 plasmid is the smallest floR-carrying plasmid reported to date. To the best of our knowledge, this is the first report of a florfenicol-resistant gene in M. haemolytica.  相似文献   
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