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1.
为分析云南省虫媒病毒的种类与遗传特征,在云南省师宗县采集库蠓进行病毒的分离与鉴定;通过全长cDNA扩增与高通量测序技术获取病毒全基因组序列,进行序列比对与系统发生树构建。结果显示,从采集的库蠓样本中分离出1株可在C6/36细胞上引起细胞病变的毒株(YNSZ043),病毒基因组为分节段双链RNA,琼脂糖凝胶电泳呈"2-4-3"的带型特征;电镜观察可见直径为70~80 nm,呈"指环状",表面具有纤维突起的病毒粒子。全基因组测序结果显示,YNSZ043毒株为版纳病毒(Banna virus,BAV),基因组大小为20 683 bp,由Seg-1(3 762 bp)至Seg-12(861 bp)12个基因节段组成,与中国BAV毒株各基因节段的核苷酸序列相似性在64.8%~99.6%之间,氨基酸序列相似性在58.8%~100%之间,在系统发生树上YNSZ043毒株与中国分离的BAV聚为一簇,形成独立的中国进化支系。对决定BAV基因型的Seg-12分析结果显示,YNSZ043毒株属于A2基因型,该毒株的Seg-5/VP5与越南分离BAV毒株的核苷酸和氨基酸序列相似性高达97.1%和97.6%,表明该毒株的Seg-5基因节段很可能与越南毒株之间发生了基因重配。研究结果丰富了中国BAV的基因组序列,为开展云南省BAV的流行病学研究提供了参考。  相似文献   
2.
A captive female square‐lipped rhinoceros born in 1993 had been showing intermittent signs of bilateral conjunctivitis and conjunctival proliferation since 1998. Periodic improvement was noted, especially in winter, but overall the condition had deteriorated over the years. Treatment with various topical, intralesional, and systemic antibiotics and glucocorticosteroids was largely ineffective, as were repeated dewormings. No primary cause for these lesions was found in biopsies taken in 2000 and 2006, although a severe infiltrate of numerous eosinophils was observed in the latter. As the condition worsened, secondary corneal changes were noted, and eventually vision was lost due to proliferative conjunctival tissue. Aggressive resection of the proliferating tissue in 2013 restored vision and submitted biopsies yielded a diagnosis of severe allergic conjunctivitis, eosinophilic granuloma, and habronematid (Habronema or Draschia) larval infection. As no other rhinoceros in the herd was affected, including two calves born to the patient who were in close contact with their mother, it was concluded the presentation was most likely due to a hypersensitivity reaction to the dead or dying larvae. Fly repellent is now regularly applied around the eye of this rhinoceros, and a protective face mask has been fitted. Ongoing periodic relapses are treated with oral ivermectin, topical antibiotics, and steroids.  相似文献   
3.
育成猪免疫学指标的测定   总被引:4,自引:0,他引:4  
6头健康长大杂交猪 ,体重 (2 5 .5± 1.4 )kg ,用于研究 7~ 11周龄猪免疫学特征。于 7、8、9、10、11周龄时 ,自前腔静脉采血 ,用显微镜法计数红、白细胞总数 ,经姬姆萨染色后作白细胞分类计数 ,用硝基蓝四氮唑(NBT)还原试验定量检测嗜中性白细胞吞噬功能 ,噻唑蓝 (MTT)比色法检测外周血中淋巴细胞转化 ,单向免疫扩散法测定血清IgG浓度 ,5 0 %溶血试验测定血清中补体总活性 ,同时 ,用植物血凝素 (PHA)皮肤试验检测迟发型超敏 (DTH)反应。结果明示 ,7~ 11周龄猪免疫反应差异不显著 (P >0 .0 5 ) ,即猪免疫系统已发育完全 ,适于用作免疫学研究的动物模型  相似文献   
4.
本试验采用粘蚊帖收集库蠓的方法,了解在鸡舍内和鸡舍外使用驱蚊草对库蠓的驱除作用。试验结果证明:使用驱蚊草在鸡舍外能够在1.5m范围内有效地减少库蠓的数量(P〈0.05):放置了驱蚊草的鸡舍相比未放置驱蚊草的鸡舍其库蠓数量明显减少(P〈0.05);另外,驱蚊草对蛋鸡的产蛋率与死淘率无明显影响。由此可见,驱蚊草有明显的驱库蠓效果,能达到预防鸡白冠病的目的,  相似文献   
5.
A virus, isolated from faba bean (Vicia faba) obtained from Algeria, was readily recognized as a tobravirus by its particle sizes and morphology. Pea (Pisum sativum) and French bean (Phaseolus vulgaris) characteristically reacted to the isolate like pea early-browning virus (PEBV), but faba bean,Antirrhinum majus, Nicotiana rustica, andN. tabacum reacted with line-pattern symptoms which were unusually brilliant on theNicotiana species. In electronmicroscope decoration tests, the isolate did not react with an antiserum to the Dutch type strain of PEBV, but with one to the broad bean yellow band (BBYB) serotype from Italy. It resembles this serotype in reaction on faba bean, but seems to differ appreciably onN. rustica, N. tabacum, andPetunia hybrida. It is described as a deviant isolate of the BBYB serotype of PEBV.All thirteen faba-bean genotypes tested were found to be susceptible to the Algerian isolate and two Dutch type strain isolates of the virus, and to react with erratic line-pattern symptoms to the Algerian isolate only. All ten genotypes of chickpea (Cicer arietinum) tested reacted hypersensitively, and four out of ten genotypes of lentil (Lens culinaris) were susceptible to the virus but reacted differentially to the three isolates. Seed transmission of PEBV, including the new isolate, in faba bean is confirmed (9% for the Algerian isolate, and over 45% for one of the Dutch type strain isolates), and seed transmission of the virus in a non-legume (N. rustica, 4%) is herewith first reported. This is the first report on the occurrence of the BBYB serotype of PEBV outside Italy, and of PEBV outside Morocco in North Africa.  相似文献   
6.
A number ofCapsicum accessions including nine species were tested for resistance to TMV based on hypersensitivity. The tobacco strain MA and the tomato strain SPS, which were both isolated from tomato, and two pathogenically distinct pepper strains P 11 and P 8, were used. Of the 73Capsicum accessions tested 58 were resistant to MA and SPS, 31 were resistant to P 11 and five were resistant to P 8.Samenvatting Om verschillen in pathogeniteit tussen twee in Nederland voorkomende paprikastammen van het TMV nader vast te stellen, werd een aantalCapsicum-herkomsten, waaronder negen soorten, op resistentie getoetst. Hierbij werden de representatieve paprika-isolaten P 11 en P 8 vergeleken met de uit tomaat afkomstige isolaten MA en SPS als vertegenwoordigers van respectievelijk de tabaks- en tomatestam van het TMV. Bij het beoordelen van de symptomen duidden lokale, necrotische vlekken en afvallen van geïnoculeerde bladeren op resistentie, systemische necrosen of mozaïeksymptomen op vatbaarheid. In deze symptomen kwamen tussen de gebruikte stammen verschillen in virulentie tot uitdrukking. Er werden echter vooral verschillen in agressiviteit waargenomen met betrekking tot zowel afzonderlijke, voor resistentie uitsplitsende,Capsicum-herkomsten als het totale aantal getoetste herkomsten. Van de ruim 73 herkomsten waren er 58 resistent tegen MA en SPS, 31 daarvan tegen P 11, maar slechts vijf daarvan tegen P 8. Deze resistentie tegen P 8 werd gevonden inC. chinense.  相似文献   
7.
Abstract This study describes 26 cats with mosquito bite hypersensitivity. Most were short-haired, free-roaming cats. Typical clinical features were seasonal (summer), symmetric miliary dermatitis on the pinnae. Mosquito bite exposure with Aedes albopictus was performed on the pinnae and the lateral thorax in five cases and three healthy cats. All sites showed weals within 20 min. Papules, which revealed eosinophilic dermatitis, were recognized during a 12–48-h period. The control cats showed only slight and transient erythema after being bitten. Intradermal skin tests with an extract of A. albopictus were performed in three cases, and Prausnitz-Küstner tests under A. albopictus bites were performed in three cases. Both tests showed weals in all cases studied, although papules were not observed. Intradermal skin tests with the control cats, and Prausnitz-Küstner tests with saline and healthy cat serum failed to produce any positive reactions. The findings indicate that mosquito bite hypersensitivity in cats is triggered by a type I hypersensitivity reaction to mosquito antigens. Certain other factors may be involved in the formation of delayed papular reactions. Whether this is a normal or abnormal reaction to mosquito bites is also discussed. Résumé— Cette étude a été réalisée sur 26 chats atteints d'hypersensibilité aux piqûres de moustiques. La plupart des chats sont des chats à poils courts vivant à l'extérieur. Les lésions cliniques sont caractérisées par une dermatite miliaire symétrique sur les pavilions auriculaires survenant l'été. Une exposition aux piqûres de moustique (Aedes albopictus) a été réalisée sur les pavilions auriculaires et sur la face latérale du thorax de 5 chats atteints et de 3 chats sains. Tous les sites d'exposition montrent des reactions à 20 minutes. Ces papules qui traduisent une dermite éosinophilique, persistent pendant 12 à 48 heures. Les chats sains ne montrent qu'un érythème transitoire après la piqûre, des tests d'intradermoréaction avec un extrait d'A. albopictus ont été réalisés dans 3 cas, des tests de Prausnitz-Küstner spécifiques dans 3 cas. Les deux tests montrent des reactions dans tous les cas étudiés bien que des papules ne soient pas observées. Ces tests réalisés sur les chats témoins, ne montrent aucune reaction, positive ou significative. Ces résultats suggèrent que l'hypersensibilité aux piqûres de moustiques chez le chat est regie par une hypersensibilité de type I à divers antigènes de moustique. D'autres facteurs doivent intervenir dans la formation des reactions papuleuses retardées. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Réactivité cutanée aux piqûres de moustiques et à leurs antigènes chez le chat.) Veterinary Dermatology 1997; 8 : 19–26.] Résumén Este estudio describe 26 gatos con hipersensibilidad a la picadura de mosquito. La mayoria eran gatos en régimen abierto de pelo corto. Las caracteristicas clinicas tipicas fueron dermatitis miliar simétrica estacional (verano) en pabellones auriculares. Se llevó a cabo una exposición a la picadura del mosquito Aedes albopictus en los pabellones y en el tórax lateral en 5 casos y 3 gatos sanos. Todas las zonas mostraron ronchas a los 20 minutos. Aparecieron pápulas con dermatitis eosinofilica a las 12 a 48 horas. Los gatos control mostraron solamente eritema leve y transitorio tras la picadura. Se realizaron pruebas cutáneas intradérmicas con extracto de A. albopictus en 3 casos y pruebas de Prausnitz-Küstner bajo picaduras de A. albopictus en 3 casos. Ambas pruebas mostraron ronchas en todos los casos estudíados, aunque no se observaron pápulas. Las pruebas intracutáneas con los gatos control y las pruebas de Prausnitz-Küstner con suero salino y suero de gatos sanos no causaron reacción positiva. Estos hallazgos indican que la hipersensibilidad a la picadura de mosquito se inicia por una hipersensibilidad de tipo I a antigenos del mosquito. Otros factores pueden estar implicados en la formación de reacciones papulares retardadas. Se discute si esta es una reacción normal o anormal a la picadura de mosquito. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Reactividad cutanea a las picaduras de mosquito y sus antigenos en el gato.) Veterinary Dermatology 1997; 8 : 19–26.] Zusammenfassung— Diese Studie beschreibt 26 Katzen mit Mückenstichhypersensibilität. Die meisten der Tiere waren kurzhaarig und hatten Freilauf. Die typischen klinischen Bilder bestanden in säsonaler (Sommer), symmetrischer miliarer Dermatitis an den Ohrmuschein. Es wurde eine Exposition auf Mückenstiche mit Aedes albopictus an den Ohrmischein und am lateralen Thorax bei 5 Patienten und 3 gesunden Katzen durchgeführt. Alle Stellen zeigten Quaddeln innerhalb von 20 Minuten. Papeln, die eine eosinophile Dermatitis enthüllten, wurden nach einer Zeitspanne von 12 bis 48 Stunden gesehen. Die Kontrollkatzen zeigten ein nur leichtes und transientes Erythem nach dem Biß. Intradermale Hauttests mit einem Extrakt von A. albopictus wurden in 3 Fallen durchgeführt und Prausnitz-Küstner-Tests unter A. albopictus-Bissen wurden in 3 Fallen durchgeführt. Beide Tests zeigten Quaddeln in alien untersuchten Fallen, obwohl Papeln nicht beobachtet wurden. In den intradermalen Hauttests bei den Kontrollkatzen und Prausnitz-Küstner-Tests mit Kochsalz-Lösung und Serum gesunder Katzen gelang es nicht, irgendweiche positiven Reaktionen zu erzeugen. Diese Befunde zeigen, daß Mückenstichhypersensibilität bei Katzen durch eine Typ 1-Hypersensibilitätsreaktion auf Mückenantigene ausgelöst wird. Bestimmte andere Faktoren können in die Bildung von verzögerten papulären Reaktionen miteinbezogen sein. Ob dies eine normale oder unnormale Reaktion auf Mückenstiche ist, wird ebenfalls diskutiert. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Hautreaktivität auf Mückenstiche und Antigene bei der Katze.) Veterinary Dermatology 1997; 8 : 19–26.]  相似文献   
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10.
Resistance at the TM-2 locus in the tomato to tomato mosaic virus   总被引:4,自引:0,他引:4  
T. J. Hall 《Euphytica》1980,29(1):189-197
Summary There are three known tomato mosaic virus (TMV) resistance factors, Tm-1, Tm-2 and Tm-2 2, in the tomato. Tm-2 2 is currently the most widely utilised in glasshouse cultivars. Both Tm-2 and Tm-22 can induce systemic necroses in response to virus infection. These are considered to be hypersensitive resistance reactions in view of the low virus concentrations in affected plants and because sub-inoculation usually fails to infect all plants possessing the same resistance gene. The literature relating to TMV resistance at the Tm-2 locus in the tomato is reviewed.Virulent strains may readily establish when Tm-1 or Tm-2 are used, but Tm-2 2 confers more effective resistance. The possible development of aggressive isolates capable of affecting Tm-2 2/Tm-22 plants is discussed. The establishment of virus types which cause systemic necrosis at normal growing temperatures is considered more likely than widespread infection from fully virulent strain 22 mutants. However, the growing of crops isolated from the TMV reservoirs in the soil considerably reduces the likelihood of even this occurring.  相似文献   
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