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81.
Second phalangeal fractures have been classified as either simple or multiple and have been managed in a variety of ways. The removal of small osteochondral fragments originating from the palmar midsagittal aspect of the proximal second phalanx is reported. This lesion has been described as a coincidental finding unrelated to lameness. Based on our clinical finding of lameness in this case and the response to an intraarticular injection of anesthetic, excision of the fragment was elected. However, the importance of confirming the significance of a radiographic lesion with local anesthesia prior to surgical intervention must be stressed.  相似文献   
82.
Abstract— To study the immune response of cats to dermatophyte infection, ten healthy cats and five cats previously infected with Microsporum canis were injected intradermally with dermatophyte glycoprotein extracts. Injection sites were observed for immediate and delayed reactions and biopsied at 24 and 48 hours after injection. All five previously-infected cats but only two of 10 control cats had immediate positive reactions to M. canis antigen. Four out of five previously-infected cats and one of 10 control cats also had reactions to Trichophyton rubrum antigen, suggesting antigenic crossreactivity between these fungal species. At 24 h after injection, four out of five previously-infected cats had delayed reactions to M. canis antigen at the injection sites; equivalent sites in all control animals were negative. The histological appearance of the delayed reactions was a superficial perivascular dermatitis, with lymphohistiocytic cells, eosinophils, mast cells, and neutrophils. This pattern is consistent with a delayed-type hypersensitivity response to fungal antigens. Special stains revealed no evidence of cutaneous basophil hypersensitivity in these reactions. Our data suggest that naturally-occurring feline dermatophytosis is accompanied by development of both humoral and cellular immune responses to the organism. Intradermal skin testing with dermatophyte antigens is a useful tool for investigating the immune response of cats to dermatophytosis. Résumé— Afin d'étudier la réponse immunitaire des chats à une infection par des dermatophytes, des intradermoréactions à l'aide d'extraits glycoprotéiques de dermatophytes ont été pratiquées sur 10 chats sains et 5 chats antérieurement infectés par Microsporum canis. Les sites d'injection ont cté observés pour lés réactions immédiates et retardées et biopsiés à 24 et 48 heures. Les 5 chats antéricurement infectés et seulement 2 des chtas témoins ont présenté des réactions immédiates à l'extrait antigénique de Microsporum canis, 4 des 5 chats antérieurement infectés et 1 des 10 chats témoins ont aussi présenté des réactions àTríchophyton rubrum, suggérant l'existence de réactions croisées entre ces deux espèces de dermatophytes. 24 heures après l'injection, 4 des 5 chats antérieurement infectés ont présenté des réactions retardées àMicrosporum canis au point d'injection. Ces mêmes tests étaient négatifs chez les animaux témoins. L'aspect histologique des réactions retardées etait celui d'une dermite périvasculaire superficielle à celles lymphohistiocylaires, éosinophiles, neutrophiles, et mastocytes. Cet aspect est compatibles avec une réaction d'hypersensibilité retardée aux antigènes fongiques. Des colorations spécifiques n'ont pas permis de mettre en évidence une hypersensibilité cutanée à basophiles dans ces réactions. Ces résultats suggèrent que l'infection naturelle par des dermatophytes chez le chat entraine le développement d'une réaction immunitaire humorale et cellulaire spécifique de ces organismes. Les intradermoréactions à l'aide d'extraits antigéniques de dermatophytes sont un bon moyen d'exploraton de la réponse immunitaire des chats lors de dermatophytle. Zausammenfassung— Um die Immunantwort von Katzen auf die Infektion mit Dermatophyten zu untersuchen, wurden bei zehn gesunden Katzen und fünf Tieren mit vorausgegangener Microsporum canis-Infektion Extrakte von Dermatophyten-Glykoprotein intradermal injiziert. Die Injektionsstellen wurden auf Sofortund Spätreaktionen kontrolliert sowie 24 und 48 Stunden nach der Injektion biopsiert. Alle fünf Katzen mit vorausgegangener Infektion, aber nur zwei der 10 Kontrolltiere zeigten eine positive Sofortreaktion auf M. canis-Antigen. Vier der fünf früher infizierten Katzen und eine der 10 Kontrollkatzen zeigten gleichzeitig Reaktionen auf Tríchophyton rumbrum-Anúgen. Dies legt den Verdacht nahe, daß zwischen diesen Pilzspezies Kreuzreaktionen auf Antigene auftreten. 24 Stunden nach der Injektion zeigten vier der fünf früher infizierten Katzen Spätreaktionen auf M. canis-Antigen an den Injektionsstellen. Entsprechende Hautstellen waren bei alien Kontrolltieren negativ. Das histologische Bild der Spätreaktionen bestand in einer oberflächlichen, perivaskulären Dermatitis mit lymphohistiozytären Zellen, eosinophilen Granulozyten, Mastzellen und neutrophilen Granulozyten. Diese Muster stimmt mit einer Hypersensibilitätsreaktion vom Spättyp auf Pilzantigene überein. Spezialfärbungen erbrachten keinen Hinweis auf eine Hypersensibilität der kutanen basophilen Granulozyten bei diesen Reaktionen. Unsere Befunde deuten en, daß natürlich auftretende Dermatomykosen bei Katzen von der Entwicklung sowohl humoraler als auch zellulärer Immunantworten auf diese Organismen begleitet werden. Intradermale Hauttests mit Dermatophytenantigenen sind ein nützliches Verfahren um die Immunantwort von Katzen auf Dermatomykosen zu untersuchen. Resumen Para estudiar la respuesta inmune de los gatos hacia la infección por dermatofítos, diez gatos sanos y cinco gatos previamente infectados con Microsporum canis fueron inyectados intradérmicamente con extractos de glicoproteina de dermatofito. En los lugares de inyección se observaron las reacciones inmediatas y posteriores y se, realizaron biopsias a los 24 y 48 horas después de la inyección. Tuvieron reacciones positivas inmediatas hacia el antígeno M. canis los cinco gatos prevaimente infectados y uno de los diez “gatos control”. Cuatro de los gatos previamente infectados y uno de los diez “gatos control” tambien reaccionaron ante el antígeno Tríchophyton rubrum, sugeriendo reactividad cruzada, antigénica entre estas especies fúngicas. A los 24 horas después de la inyección, cuatro des los cinco gatos previamente infectados presentaron reacciones posteriores hacia el antígeno M. canis en los lugares de la inyección; los lugares equivalentes en todos los animales control fueron negativos. La aparición histológica de las reacciones posteriores consistía en una dermatitis perivascular superficial, con celulas linfohistiocíticas, eosinofilos, mastocitos y neutrofilos. Este patrón es consistente con una hipersensibilidad de dipo retrasado en respuesta a antígenos fúngicos. Manchas especiales revelaron la no evidencia de hipersensibilidad de basófilos cutaneous en estas reacciones. Nuestros datos sugieron que la dermatofitosis felina producida de forma natural va acompañada del desarrollo de respuestas inmunes humorales y celulares hacía el organismo. La prueba intradérmica con antígenos dermatofítos es útil para investigar la respuestra inmunológica de los gatos hacia dermatofitosis.  相似文献   
83.
Efficiency of cloning has remained low and in spite of attempts to improve this technology, many reconstructed embryos do not implant or are lost during early pregnancy. Chromosomal aberrations, deviant gene expression patterns and abnormal regulation of cell death may be involved in this increased early embryonic loss. Here, we investigate the chronological onset of both apoptotic changes in nuclear morphology and DNA degradation [detected by transferase-mediated dUTP nick-end labelling (TUNEL) reaction] in bovine two-cell- to blastocyst-stage embryos. Such embryos were generated either by reconstruction with nuclear transfer from quiescent granulosa cells or by regular in vitro embryo production. Nuclear condensation was observed from the two-cell stage and TUNEL labelling was observed from the six-cell stage in reconstructed embryos, whereas nuclear condensation was evident from the eight-cell stage and TUNEL labelling from the 13-cell stage in embryos derived in vitro. Furthermore, reconstructed embryos displayed elevated ratios of embryos containing apoptotic nuclei at pre-compaction stages and higher indices of apoptotic nuclei in morula and blastocyst stages when compared with in vitro-produced embryos.  相似文献   
84.
Measuring ammonia(NH3)volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in agriculture.The small area of chambers used for NH3volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are adopted.Our aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH3volatilization in urea-amended field plots and ii)to define the critical period of NH3-N losses during which the concentration of sampling effort is capable of reducing uncertainty.The use of only one chamber covering 0.015%of the plot(51.84 m2)generates a value of NH3-N loss within an expected margin of error of 30%around the true mean.To reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per plot.Concentrating the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH3volatilization.This strategy enhances the power of detection of NH3-N loss abatement in field experiments using chambers.  相似文献   
85.
Air transport of livestock occurs frequently from most Australian major cities. The total journey time starts with road transport from the farm or pre-export facility to the departing airport where livestock are crated, and ends with the unloading of animals at the premises or farm in the importing country. We reviewed the literature regarding airfreight and conclude that there was minimal information on current practices within this industry, particularly for procedures after arrival at the Australian airport, and during the on-board phase.  相似文献   
86.
87.
The response of a ryegrass sward to wheel traffic and applied nitrogen   总被引:1,自引:0,他引:1  
The dry matter and nitrogen yield and estimated metabolizable energy of perennial ryegrass grown for silage were recorded from 1988 to 1990 for three levels of wheel traffic (zero, light and severe) at four rates of nitrogen fertilizer. The traffic treatments were applied by tractor wheels in the spring and summer of 1987 and in the spring of 1988 and 1990. First-harvest yields were reduced consistently by severe traffic: for example, at a rate of 100kg N ha-1, dry matter (DM) produced in the severe treatment was 58, 72 and 84% of that in the zero traffic treatment in successive years. Wheel traffic effects on yield were markedly smaller at second and third cuts than at first cut. Nitrogen uptake and apparent recovery of fertilizer nitrogen were usually less after the relatively severe traffic treatment than after zero or light traffic treatments. Denitrification fluxes, measured in the second and third years, indicated that gaseous losses of nitrogen were largest when soil compaction was greatest.
Reduction of herbage yield at first cut in 1989, the year in which no wheel traffic had been applied at the start of the growing season, indicated that impaired soil physical conditions were implicated, quite apart from possible damage to the grass plants. Soil structure was damaged in both light and severe traffic treatments: in the latter, the volume of air-filled pores during the wetter periods early in each growing season was especially small (<4%, v/v). It seemed likely, therefore, that poor aeration was a key factor in limiting both grass growth and nitrogen utilization.
The effect of wheel traffic on herbage production tended to decline over the 3-year period of the experiment. However, it was not clear whether that trend was primarily a consequence of a progressive improvement in the structure of the most dense soil, or was a degree of variation caused by differences in weather patterns between years.  相似文献   
88.
Soil and crop responses to zero, small and large tyre/soil contact stresses applied by tractors were studied on a newly reseeded ryegrass sward during 1987 and 1988. The compactive efforts, applied during winter or at the time of spring fertilizer application or at first harvest, were sufficient to increase significantly bulk density in the topsoil layer compared with that in a zero traffic control treatment. The largest increases in soil bulk density occurred after spring-time traffic in the first year (1987) of the experiment. In both years, the resulting soil conditions after heavy compaction were relatively unconducive to primary grass growth and first cut yields; the soil was wetter (less well aerated), of greater strength and colder in the early spring, and warmer in the late spring than the soil in the zero and more lightly compacted treatments. During a relatively wet summer (1987) there were significant benefits to second and third cut yields from minimizing compaction; in the relatively dry summer of 1988 there were no compaction effects at second cut. In both years, impaired uptake of nitrogen was related closely to increased amount of traffic and soil density.  相似文献   
89.
Abstract. Micropogon undulatus L. were sampled from Galveston Bay, Texas, and transported to the research laboratory. Groups of five fish were exposed to 5 and 10% dilutions of the water soluble fraction (WSF) of southern Louisiana crude oil for 1, 3, 7, 14 and 21 days. Selected histochemical parameters of liver sections from control and WSF-exposed fish were evaluated. Glycogen was reduced in amount while glucose-6-phosphate dehydrogenase, lipid and cholesterol were increased in liver sections of WSF-exposed fish. These observations support a hypothesis that exposure to petroleum hydrocarbons increases mixed-function oxidase activity. The alterations were more obvious in sections from fish exposed to the higher level of the WSF. The histochemical parameters appeared most altered in hepatocytes near afferent hepatic blood vessels. These hepatocytes were the first cells of the liver to contact the pollutants.  相似文献   
90.
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