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排序方式: 共有299条查询结果,搜索用时 15 毫秒
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Chou J Wünschmann A Hodzic E Borjesson DL 《Journal of the American Veterinary Medical Association》2006,229(8):1260-1265
OBJECTIVE: To develop a quantitative PCR assay for detection of Borrelia burgdorferi DNA in formalin-fixed, paraffin-embedded tissues; compare results of this assay with results of immunohistochemical staining of tissues from seropositive dogs; and determine whether B burgdorferi DNA could be detected in renal tissues from dogs with presumptive Lyme nephritis. DESIGN: Cohort study. SAMPLE POPULATION: Archived tissue samples from 58 dogs. PROCEDURES: A quantitative PCR assay was performed on formalin-fixed, paraffin-embedded tissue sections from the dogs. Results were compared with results of immunohistochemical staining, B burgdorferi serostatus, clinical signs, and necropsy findings. RESULTS: 38 dogs were classified as having positive or equivocal results for Lyme borreliosis, and 20 were classified as having negative results on the basis of clinical signs, serologic findings, and pathologic abnormalities. Borrelia burgdorferi DNA was amplified from tissue samples from only 4 (7%) dogs, all of which had been classified as having positive or equivocal results for Lyme borreliosis and had signs of presumptive Lyme nephritis. Results of PCR assays of renal tissue were positive for only 1 dog, and there was no agreement between results of immunohistochemical staining (ie, detection of B burgdorferi antigen) and results of the PCR assay (ie, detection of B burgdorferi DNA) for renal tissues. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that detection of B burgdorferi DNA in formalin-fixed, paraffin-embedded tissues is feasible, but that intact B burgdorferi DNA is rarely found in tissues from naturally infected dogs, even tissues from dogs with presumptive Lyme borreliosis. Further, findings support the contention that Lyme nephritis may be a sterile, immune complex disease. 相似文献
245.
Chang MH Lo DY Chou CC Lee WM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(9):1009-1011
Carbonic anhydrase (CA) family is discovered in various species including mammals, avians and even plants, but it is rarely reported in fishes. Ten Pond Loaches were used in this study. The results indicated that no evidence of distribution of CA in esophagus. Nonetheless CA was found in the mucosal epithelium of stomach and in the villous epithelium of intestine demonstrated histochemically by the numerous black sedimentation of cobaltous sulfide (CoS) in these areas. In addition, black sedimentations of CoS were also found in all the vascular endothelium examined and red blood cells of digestive tract. The distribution of CA in Pond loach was more closely resemble amphibians than to other species, suggesting evolutional adaptation for Pond loach in aquatic environments. 相似文献
246.
Kwo-Chang Ueng Ching-Wen Lou Shih-Peng Wen Shih-Ya Chou Jia-Horng Lin 《Fibers and Polymers》2016,17(4):608-614
This study aims to develop reticular, tubular polyvinyl alcohol (PVA) vascular stents, and then examines their structure and properties. PVA fibers are knitted, followed by being immersed in a polycaprolactone (PCL) solution and thermally treated in order to form vascular stents. The test results indicate that the combination of a loop structure of knits and the PCL film that is adhered to fibers can effectively form elastic, compression-resistant PVA vascular stents. The vascular stents retain a stabilized path after an in vitro degradation, and thus this study successfully creates the desired elastic PVA vascular stents. 相似文献
247.
高效液相色谱法同时测定水产品中四种氟喹诺酮类药物残留前处理条件的优化 总被引:4,自引:0,他引:4
建立了同时测定水产品中氧氟沙星、诺氟沙星、环丙沙星、恩诺沙星4种氟喹诺酮类药物残留量的高效液相色谱方法,并对提取和净化等前处理条件进行了优化。目标化合物采用高效液相色谱-荧光检测器检测,外标法定量。对草鱼、鳙鱼、大黄鱼、虾进行检测分析,添加4、10、100、1000μg/kg浓度水平时,回收率为68.5%~106.6%,相对标准偏差0.80%~9.16%,方法的检出限为1.5μg/kg,定量限为4μg/kg。 相似文献
248.
(1) Factors influencing the survival of chickens in the first week of life in Taiwan were identified by modelling data from 63% of the annual national broiler production database (4769 broiler flocks). (2) Broiler chicks raised in rooms with open-curtain ventilation had the lowest mean first week cumulative mortality (CM), 1.30%, relative to those raised in rooms with negative pressure ventilation (1.42%) and water-cooled ventilation (1.37%). Increasing flock size reduced the CM. Broiler chicks shipped distances within 50 km had the lowest CM (1.22%), while broiler chicks raised in mountain areas showed the highest CM (1.65%). (3) Multiple regression analysis results indicate that ventilation type, flock size, shipping distance and delivery route influence CM in broiler chickens. Broiler chicks kept in rooms with negative pressure ventilation have an 11.22% greater CM compared to those in rooms with open-curtain ventilation. For each 1000-chicken increase in flock size, CM is reduced by 0.12%. For each kilometre increase in shipping distance, CM increases by 0.05%. Broiler chicks delivered via mountain routes show a 9.48% increase in CM compared to delivery via flat terrain. (4) Negative pressure ventilation and delivery via mountain routes are the most critical factors affecting the survival of chicks up to one week old. 相似文献
249.
Detection of florfenicol resistance genes in Riemerella anatipestifer isolated from ducks and geese 总被引:1,自引:0,他引:1
The cat gene, coding for chloramphenicol acetyltransferase has been reported for conferring the chloramphenicol resistance for Riemerella anatipestifer. Chloramphenicol acetyltransferases, however, are unable to inactivate florfenicol. In this study, 66 R. anatipestifer isolates were investigated for their susceptibility to chloramphenicol and florfenicol and the presence of floR gene. Results showed nine florfenicol intermediate or resistant R. anatipestifer isolates were all floR positive. The expression of floR gene in E. coli and inhibition studies with PAβN indicated that the floR gene was as an efflux pump conferring resistance to both chloramphenicol and florfenicol. Southern hybridization revealed the floR was located in the plasmid DNA of five isolates and in the chromosomal DNA of four isolates. Furthermore, two novel floR-carrying plasmids designated pRA0726 and pRA0846 were sequenced completely. pRA0726 was 11,704 bp in size with 10 putative open reading frames which included the floR, catB and bla(OXA-209) resistance genes. The most differences between sequences of pRA0846 and pRA0726 were the absence of a bla(OXA-209) gene and the deletion of 321 nucleotides of orf1 in pRA0846. Plasmid curing tests demonstrated that pRA0726 carried functional coding proteins for resistance to phenicol and β-lactam antimicrobials. To the best of our knowledge, this is the first report of presence of the floR and bla(OXA-209) resistance genes in R. anatipestifer. 相似文献
250.
The Efficacy of Inactivated Photobacterium damselae subsp. piscicida Combined with Levan/Alum as Vaccine against Photobacteriosis in Cobia,Rachycentron canadum 下载免费PDF全文
Jiin‐Ju Guo Mei‐Ying Huang Jia‐Wei Hong Ya‐Chu Chuang Ruey‐Ling Chou Yan‐Horn Lee Tzyy‐Ing Chen 《Journal of the World Aquaculture Society》2015,46(5):549-556
Photobacterium damselae subsp. piscicida (Phdp) is a major pathogen of cultured cobia (Rachycentron canadum), a primary target species for offshore cage culture in Taiwan. Serum antibody titers as well as efficiency and duration of protection against Phdp were evaluated following intraperitoneal administration of a candidate vaccine prepared with formalin‐inactivated whole cells in combination with levan/alum adjuvants. The results showed vaccinates delayed the disease onset and had significantly (P < 0.05) less mortality than control nonvaccinates during Days 21–105 postvaccination with highest relative percentage of survival (RPS) and antibody titer up to 81.4% and 1:614, respectively. There was a highly significant positive linear correlation between the RPS and antibody titer (R2 = 0.841). Long‐lasting and significant protection against Phdp can be achieved with inactivated Phdp plus levan/alum, a potential cobia vaccine against photobacteriosis. Levan/alum complex may represent a promising adjuvant formula for the development of a Phdp vaccine. 相似文献