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51.
对2006~2009年河北省“猪高热病”的主要病原进行了调查分析。结果表明,猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒Ⅱ型(PCV-2)、猪伪狂犬病毒(PRv)、猪瘟病毒(CSFV)、副猪嗜血杆菌(HPS)、胸膜肺炎放线茵(APP)、链球菌(S.S)、大肠杆菌(E。coli)、沙门氏菌(Sal.)和巴氏杆菌(Pro)的总检出率分别为64.52%、30.27%、11.26%、6.13%、3.10%、2.58%、1.46%、1.11%、1.08%和0.10%。其中高致病性猪繁殖与呼吸综合征病毒(HP—PKP.SV)和经典猪繁殖与呼吸综合征病毒(C—PV.P.SV)总检出率分别为60.92%和3.60%。HP—PRIKSV同其他病原体混合感染比较普遍,感染以二重感染、三重感染为主。总之,河北省“猪高热病”的主要致病病原是HP-PRRSV,并多与PCV-2、PRV、CSFV、HPS、APP、E.cold、S.S和Sal.、Pm等病原体中的-种或几种病原混合感染或继发感染-种“综合症候群”型疫病。  相似文献   
52.
食源性致病菌是食源性疾病的重要诱因,早期的筛查技术已不能满足对食源性致病菌的快速、准确检测要求。核酸适配体因其小尺寸、易修饰、亲和性高、热稳定等优点而被广泛应用,研究者们运用核酸适配体传感器开发了针对食源性致病菌的众多检测方法,用于快速筛查食源性致病菌。该文介绍了食源性致病菌的常用检测方法,总结归纳了核酸适配体的筛选程序,列举了核酸适配体传感器在食源性致病菌检测中的应用,分析了其在应对样品的快速高效检测要求时的发展趋势,以求为食源性致病菌的检测方法改进提供更多思路。  相似文献   
53.
The combined effects of a sanitizer mixture, ultraviolet-C (UV-C), and modified atmosphere packaging (MAP) on the quality of non-inoculated and inoculated (Escherichia coli O157:H7 and Salmonella typhimurium) buckwheat sprouts were examined. Buckwheat sprouts were treated with a sanitizer mixture (comprising 100 mg L−1 aqueous ClO2 and 0.3% fumaric acid) and 2 kJ m−2 UV-C, packaged under two different conditions (air and CO2 gas) and storage for 8 d at 4 °C. The combination of the sanitizer mixture and UV-C treatment reduced the initial counts of preexisting microorganisms in the buckwheat sprouts by 1.9 log CFU g−1 and reduced the initial inoculated counts of E. coli O157:H7 and S. typhimurium on buckwheat sprouts by 3.0 and 2.3 log CFU g−1, respectively. The preexisting microorganisms and inoculated pathogens in buckwheat sprouts packaged under CO2 gas were significantly reduced during storage following the combined treatment compared to those of the control by above 95%. Differences in Hunter L*, a*, and b* values among the treatments were negligible. The combined sanitizer mixture and UV-C treatment increased the sprout rutin content by 147%, but there was no significant difference in 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity between treatments during storage. Therefore, the combination of sanitizer mixture made from aqueous ClO2 and fumaric acid, UV-C irradiation, and MAP can improve the microbial safety and quality of buckwheat sprouts.  相似文献   
54.
由于良好的抗菌活性和稳定的性能,D-柠檬烯纳米乳被广泛报道。研究D-柠檬烯纳米乳对伤寒杆菌,乙型副伤寒杆菌和痢疾志贺氏菌在37℃下培养24 h的抑菌活性,并在4℃牛肉中于第1 d、2 d、3 d分别检测对伤寒沙门氏菌,痢疾杆菌来评价其抑制效果。利用超声乳化法制备D-柠檬烯纳米乳。在最小抑菌浓度(MIC)实验中,D-柠檬烯纳米乳对三种受试菌的最小抑菌浓度为2.5 mg/m L。在牛肉试验中,基于MIC,D-柠檬烯纳米乳在牛肉中的添加浓度分别为40 mg/m L,20 mg/m L和10 mg/m L,20 mg/m L和10 mg/m L稀释液,结果两种受试菌最好的抑制浓度和时间均相同,分别是40 mg/m L和24 h。该研究表明D-柠檬烯纳米乳应用于食品中可能是食品安全的有效解决方案。  相似文献   
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57.
In Côte d’Ivoire, limited information are available on vector-borne pathogens, their prevalence and distribution. Here, we assess the occurrence and diversity of canine vector-borne diseases (CVBDs) in Abidjan and Yamoussoukro cities. Blood from a total of 123 dogs were tested for Leishmania infantum and Ehrlichia canis antibodies and screened for Leishmania and Trypanosoma spp., Piroplasmida, Filariidae and Anaplasmataceae by PCR and sequencing. Among dogs, 39 % were positive for at least one pathogen. Seroprevalences were: 15.4 % and 12.2 % for L. infantum and E. canis, respectively. DNA of L. infantum and T. congolense (4.1 %), Baabesia vogeli (1.6 %), Filariidae (Dirofilaria immitis, D. repens and Acanthocheilonema reconditum) (10.6 %) has been detected. Anaplasmataceae were detected in (17.1 %) and E. canis was the only identified specie. Co-infections were observed in 13.8 % of dogs: E. canis-L. infantum co-infection was the most prevalent (4.9 %). Age, breed and sex of dogs do not seem to influence infections. Village dogs were more susceptible to CVBDs than kennel dogs (PV = 0.0000008). This study reports for the first time the presence of L. infantum, B. vogeli, A. reconditum, D. immitis and D. repens in dogs from Côte d’Ivoire and determines the prevalence and diversity of CVBD pathogens. The results indicate that human and animal pathogens are abundant in Ivoirian dogs which requires attention of veterinarians, physicians and authorities against these diseases, especially against major zoonosis such as visceral leishmaniasis (L. infantum).  相似文献   
58.
Field studies were carried out to determine whether ticks are being imported into the British Isles on migratory birds. During spring and autumn migration 2004, ticks were collected from ringed birds at 11 bird observatories and 3 inland Riparia riparia colonies. A total of 38 ticks of 4 species (Ixodes ricinus, I. frontalis, I. lividus, I. arboricola) were collected from 12 species of bird. Ticks were tested for viruses in the Flavivirus and Nairovirus genera, with no positives found. This data demonstrates that ticks are being imported into the British Isles on migratory birds with future work recommended to determine the quantity of ticks imported and to detect low prevalence pathogens.  相似文献   
59.
为初步了解并分析酒泉市部分地区羊肉制品中食源性致病菌的污染情况,于2015—2017年对酒泉市5个县市随机采集羊肉制品827份,参照食品国家安全标准对采集的样品中沙门氏菌、金黄色葡萄球菌、大肠杆菌O157:H7、副溶血性孤菌和单核细胞增生李斯特菌污染情况进行了调查。结果显示:共有116份样品被检测出携带食源性致病菌,检出率14.03%,其中金黄色葡萄球菌74份(8.95%)、沙门氏菌23份(2.78%)、副溶血性孤菌12份(1.45%)、单核细胞增生李斯特菌7份(0.85%),没有检出大肠杆菌O157:H7;2015—2017年检出率分别为24.05%、12.09%和7.75%;不同羊肉制品中以油炸肉检出率最高(48.65%),生肉最低(5.67%)。说明酒泉市羊肉制品中食源性病菌污染较为严重,其中主要以沙门氏菌和金黄色葡萄球菌为主,给消费者健康造成潜在的威胁,相关部门需要提高食品安全监管力度。  相似文献   
60.
AIM:To investigate the effects of titanium dioxide (TiO2) nanotube arrays on the early adhesion behavior of Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) and Actinobacillus actinomycetemcomitans (Aa) before and after loaded with minocycline hydrochloride (MN). METHODS:TiO2 nanotube arrays were prepared by ano-dization and loaded with MN. Titanium slices were divided into 3 groups according to different treatment methods:pure polishing titanium (Ti) group, TiO2 nanotube titanium (TiO2) group, and MN (120 μg) TiO2 nanotube titanium (MN TiO2) group. The antibacterial properties of the titanium tablets were evaluated by the bacteriostasis test.RESULTS:The Ti had no antibacterial activity. The antibacterial activity of TiO2 to Aa, Pg and Tf was poor, with only about 20% of antibacterial rate after 4 h. After loaded with MN, its antibacterial activity was enhanced, and the antibacterial rate was up to 77% after 4 h.CONCLUSION:No antibacterial activity in the Ti group was observed. If TiO2 nanotube arrays were formed on the surface and MN was loaded, the antibacterial activity on periodontal pathogens was stronger.  相似文献   
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