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61.
Nitrogen (N) fluxes of a slope mire in the German Harz Mountains were monitored to study the effect of increased N deposition on the N retention of the mire. In addition, the N content of mire pore water beneath different plant species was analyzed to assess N retention ability of plants. Atmospheric N deposition at the study site was 4.9?±?0.4 g N m?2 year?1 averaged for the study period of 2002 and 2003, with forest stand deposition being the largest share. Discharge was the main output pathway of N with a rate of 1.9?±?0.3 g N m?2 year?1. The mire showed a high N retention rate of 67%. Short-term N accumulation rate was 3.9 g N m?2 year?1. Differences in mire pore water N concentration under different vegetation cover indicate a lower N retention ability for ombrotrophic Sphagnum plants.  相似文献   
62.
<正>在上世纪20年代一些测试方法开始发展,这些方法现在被统称为图像成形法(Picture forming methods)。其中最具代表意义的是氯化铜结晶法(copper chloride crystal-  相似文献   
63.
Selection and establishment of reserves was often done unplanned and uncoordinated between regions. Systematic conservation planning provides tools to identify optimally located priority areas for conservation. Planning for multiple species promises adequate provision for the needs of a range of threatened species simultaneously. Several studies apply the set-covering problem by minimizing resources for given conservation targets of multiple species. We extend this method by also considering different degrees of coordination in multiple-species conservation planning and representing reserve sizes endogenously. A deterministic, spatially explicit programming model solved with mixed integer programming is used to represent minimum habitat area thresholds for all included biodiversity features. The empirical model application to European wetland species addresses five different scenarios of coordination in conservation planning, including taxonomic, political, and biogeographical coordination of planning. Our approach illustrates and quantifies the efficiency of multi-species conservation activities. We show that maximum coordination in conservation planning enhances area efficiency by 30% compared to no coordination. Furthermore, strong coordination in conservation planning does not only reduce the area requirement, but synergy effects even enable the conservation features to achieve higher conservation objectives. Spatial subdivision of planning, however, leads to highest area requirements and less conservation target achievement.  相似文献   
64.
Paratuberculosis is mainly an infectious disease of ruminants with worldwide distribution. Infection occurs in early stages of life. Other animal species beyond ruminants are rarely affected, however, experimental and natural infections are possible. A case of paratuberculosis in a miniature donkey (Equus asinus f. asinus) with typical clinical and pathomorphological changes is reported here. Lesions were mainly observed in the intestine. Causative for the profuse diarrhoea with emaciation was massive diffuse granulomatous enteritis involving large quantities of acid-fast organism mainly in macrophages. Granulomatous inflammation with acid-fast bacilli again in macrophages to a lesser degree could be detected in the liver. Mycobacterium avium subsp. paratuberculosis (MAP) was isolated from intestinal contents after an incubation period of four weeks. MAP-specific DNA (IS900 and f57) was detected by polymerase chain reaction in culture material. Additionally MAP-isolates were characterized by multi-target genotyping (MIRU-VNTR- and MLSSR-typing). Isolates belonged to the Type II group and exhibited a unique genotype different from other MAP strains in Germany. The donkey originated from a donkey breeding farm in France with intensive free ranging cattle in the neighbourhood and could have been infected there. Donkeys should be considered as paratuberculosis-susceptible animals in exceptional cases and as possible reservoirs or disseminators of infection.  相似文献   
65.
In order to simplify the design of representative studies in animal populations the structural differences of animal husbandry (cattle, pigs and laying hens) in Germany were characterised. Several regions were defined and thus districts identified which are typical for the respective region and can be regarded as representatives for the whole region. Data on animal husbandry as well as human population per district originated from the Federal Statistical Office and were linked to the geometric data of the Federal Agency for Cartography and Geodesy. By this, data of "livestock units/square kilometre area" and "farms/square kilometre area" per district were calculated using methods of the spatial statistics Global Moran's Index, Anselin Local Moran's Index and Getis-Ord Gi*. With the help of these analyses six clusters could be identified which resulted in four large (Middle, Northwest, East, and South) and one smaller region (Northern Upper-Rhine) respecting the federal state borders. These regions differed significantly regarding animal and farm densities. The selection of typical districts was carried out with the help of the respective animal and farm data of the species pigs, dairy cattle and laying hens. The means of the selected districts (three to six per region) were within the 60%- and the 80%-percentile of at least two of the analysed variables. Concerning the region Northern Upper-Rhine no representative district was selected. This presented regionalisation including representative districts can be used for the design of scientific studies that are associated with animal husbandry in Germany.  相似文献   
66.
The aim of the present study was to provide current data on the prevalence of anti-Yersinia-antibodies in Bavarian slaughtering pigs. The recomBlot Westernblot assay based on five recombinantly produced Yersinia Outer Proteins (YopD, YopE, YopH, YopM, V-antigen) is well evaluated for the use in the diagnosis of human yersiniosis and proved to be also a valuable tool for the detection of porcine antibodies. 965 out of 1002 meat juice samples collected in 53 Bavarian pig farms contained anti-Yop/V-Ag-antibodies. Only blots with three or more detectable signals were considered as positive. On the basis of these results a possible previous history of Yersinia infection was detected in 45.4% of the pigs and all of the pig farms. The high prevalence of anti-Yersinia-antibodies found in this investigation demonstrates the need for further epidemiological surveillance and animal studies to assess consumers' endangering.  相似文献   
67.
In Bavaria a BHV-1 eradication program was initiated in 1986 and was changed to a compulsory program in 1998. The eradication success increased progressively from < 50% in 1986 to 87% of the farms in 2002. BHV 1-free farms are controlled by bulk milk serology twice a year along with blood serology in animals that are negative but from herds where positive field virus infected animals are present. All serological tests are performed with an indirect ELISA test, all positive results are confirmed by a gB ELISA. Currently about 100.000 virus infected cattle are in Bavarian herds, approximately 80% of these animals are in heavily infected herds (> 10 infected animals). These herds comprise about 5% of all Bavarian herds. The eradication of the virus in these heavily infected herds is the most diifficult, whereas the prevention of new infections appears controllable. In this review current problems in BHV1 eradication are named and possible improvements are discussed.  相似文献   
68.
Monoterpenoid compounds extracted from wood of Scots pine, Pinus sylvestris L, synergized the attraction of the old-house borer, Hylotrupes bajulus (L), to the male pheromone (3R)-3-hydroxy-2-hexanone ((3R)-ketol) + 1-butanol. Glasshouse experiments using ground traps baited with extracts derived from Scots pine wood or the monoterpenes (+)-alpha-pinene, (-)-verbenone, (-)-trans-pinocarveol and (+)-terpinen-4-ol attracted significantly more H bajulus females, but caught fewer of them, than the synthetic pheromone mixture alone. Traps baited with higher concentrations of the monoterpene mixture attracted fewer females than those baited with lower dosages, whilst very high concentrations of the mixture (6-10 vials) caught no insects. However, a combination of (3R)-ketol + 1-butanol or (+/-)-3-ketol + 1-butanol with monoterpenes resulted in the capture of significantly more females than either the sex pheromone or the monoterpene mixture alone. Traps baited with a blend of the male's sex pheromone or the monoterpenes attracted significantly more, but caught fewer, males than females. Here again, a combination of the above blends enhanced the attraction of males significantly when compared with the attractancy of either of the compounds/mixtures used alone.  相似文献   
69.
Zusammenfassung Wachstumskurven vom bakteriellen Pflanzenkrebs (crown gall) an verschiedenen Wirtspflanzen (Pelargonium-Arten,Vicia faba, Bryophyllum daigremontianum) zeigen einen Verlauf, der dem anderer biologischer Wachstumsvorgänge außerordentlich ähnlich ist. In den Kurven verschiedener Sippen kommen genetisch bedingte Einflüsse des Wirtsorganismus auf die Tumorentwicklung zum Ausdruck. Sogar die Partnergewebe von Periklinalchimären können in dieser Beziehung unterschiedlich reagieren. Die Kurven schnell wachsender Tumoren nähern sich einer Grenzkurve, die als die Wachstumskurve voll alterierter Tumoren anzusehen ist. Bei Sippen mit langsam wachsenden Tumoren ist häufig die Anfangsphase gehemmt. Tumoranfälligkeit und Tumorwüchsigkeit sind in der Regel gleichsinnig beeinflußt.Mit dem Aufhören des Streckungswachstums entstehen weniger und kleinere Tumoren (Bryophyllum-Blätter,Vicia). Kinetin macht ältere Blätter vonBryophyllum nicht anfälliger. Die heranwachsenden Brutknospen hemmen die Entwicklung von Tumoren an den Blättern. Dekapitieren der Pflanzen fördert dagegen die Tumoren und überdeckt den Hemmungseffekt der Brutknospen. Diese und andere Versuche zeigen, daß pflanzliche Tumoren während der Induktionsphase und in geringerem Ausmaß auch noch später durch physiologische Mechanismen beeinflußbar sind.
Summary Growth diagrams of crown gall tumors on different host plants (species ofPelargonium, Vicia faba, Bryophyllum daigremontianum) are very similar to those of other biological growth processes. Curves of different taxa reveal that development of tumors is influenced by the genetic constitution of host organism. Even partner-tissues of periclinal chimerae may react differently. Curves of rapidly growing tumors approach a limit which should be regarded as growth curve of fully alterated tumors. The initial phase of slowly growing tumors is often retarded. Sensitiveness to tumors and growth of tumors usually are influenced simultaneously.With the end of leaf growth fewer and smaller tumors arise (Bryophyllum-leaves,Vicia). Kinetin does not increase sensitivity to tumors in older leaves ofBryophyllum. Growing adventitious leaf-buds retard tumor development in leaves. Decapitating of plants favours tumors and covers the retarding effect of leaf buds. These and other experiments show that plant tumors may be influenced by physiological mechanisms during the inductive phase, and, though to a lesser extent, also later on.

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70.
Feline panleukopenia is a frequent and commonly fatal disease of cats. Recent published studies have raised suspicions that some cats fail to develop antibodies after vaccination. The purpose of this study was to assess the prevalence of antibodies against feline panleukopenia virus (FPV) in cats in Southern Germany, and to identify factors that are associated with a lack of antibodies. In total, 350 cats presented to the Clinic of Small Animal Medicine, Ludwig-Maximilians-Universitaet were randomly included in the study. Information regarding signalment, origin, environment, lifestyle, housing conditions, health status, chronic diseases, glucocorticoid therapy, and vaccination status were collected. Antibodies were detected by haemagglutination inhibition test. Asymptomatic chi-squared tests and univariable logistic regression were used to investigate associations between a lack of antibodies and the different variables. Associations determined to be statistically significant at P < 0.1 were verified by a multivariable logistic regression analysis.Of the 350 cats, 103 (29.4%) had no antibodies against FPV. Chronic kidney disease, neoplasia, glucocorticoid therapy, and vaccination status were significantly associated with a lack of antibodies. The cats with no antibodies were likely to have inadequate immunity against panleukopenia and those with chronic diseases or receiving glucocorticoids were less likely to be protected.  相似文献   
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