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81.
82.
In the Asian elephant, wetness akin to perspiration is commonly observed on the cuticles and interdigital areas of the feet; this observation has lead to speculation regarding the existence of an interdigital gland. Our goal was to search for interdigital glands and characterise them morphologically, histochemically, and immunohistochemically. Necropsy samples of interdigital areas from two Asian elephants were obtained. Multiple sections were fixed and processed routinely, then stained with hematoxylin/eosin and differential mucin stains. Immunohistochemistry was also performed for cytokeratins 8 and 10. Interdigital glands resembling human eccrine glands were detected deep within the reticular dermis. Histochemical staining indicated neutral mucopolysaccharides and nonsulphated acid mucopolysaccharides in glandular secretions, and the glandular epithelium also showed immunoreactivity to cytokeratins 8 and 10. Both the histochemical and immunohistochemical staining patterns are analogous to human eccrine structures. This study shows with certainty that Asian elephants possess sweat glands as they are defined histologically.  相似文献   
83.
BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa.  相似文献   
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Zusammenfassung Bei 46 Arten der GattungenTriticum undAegilops wurden anatomische Untersuchungen im Bereich der Organe Wurzel, Halm, Blattspreite, Ährenspindel, Spelzen, Blüte und Karyopse mittels gefärbter Hand- bzw. Mikrotomschnitte vorgenommen. Bedingt durch die kleineren Sproßorgane vonAegilops ergaben sich dort oft geringere Zellgrößen. Häufig waren auch mit der Ploidiestufe korrelierte Merkmale anzutreffen. In einigen Fällen ließ sich der Einfluß bestimmter Arten bzw. Genome auf die Merkmalsausprägung der allopolyploiden Sippen deutlich nachweisen, wofür als besonders klares BeispielAegilops tauschii mit seinem Einfluß auf die hexaploiden Weizenarten und auf die SektionVertebrata der GattungAegilops zu nennen ist. Innerhalb der GattungTriticum konnte eine Beziehung der Weizenarten mit einem G-Genom zu den diploiden Arten dieser Gattung durch Merkmale aller Organe belegt werden, während mit den übrigen Weizenarten weniger Ähnlichkeit besteht. Ein Merkmal im Halmbereich gibt sogar einen Hinweis auf die mögliche Beteiligung vonTriticum urartu an der Evolution der Weizenarten mit dem G-Genom. Nach Blatt- und Spelzenmerkmalen lassen sich die meisten tetraploidenTriticum- Sippen. mit einem AB-Genom zwei verschiedenen Gruppen zuordnen. Die diploiden Weizenarten erwiesen sich als gut charakterisierbare Gruppe. Echte anatomische Unterschiede zwischen Wild- und Kulturweizen bestehen nur in Bezug auf die Brüchigkeit der Ährenspindel. Innerhalb der GattungAegilops stehen sich die SektionenSitopsis undAmblyopyrum sehr nahe und sind auch denTriticum- Sippen viel ähnlicher als die übrigen Vertreter ihrer Gattung. Ein genauerer Hinweis auf den möglichen Donor des B-Genoms läßt sich aber anhand der anatomischen Merkmale nicht geben. Im gesamten Verwandtschaftskreis vonTriticum undAegkilops nur einmal auftretende Merkmale sind sehr selten, jedoch gibt es in mehreren Gruppen relativ isoliert stehende Arten. Zahlreiche anatomische Merkmale sind durch eine so große infraspezifische Variationsbreite gekennzeichnet, daß sie keine phylogenetische Aussage erlauben.
Anatomical studies within the generaTriticum L. andAegilops L. (Gramineae)
Summary The anatomical characters of the root, culm, leaf lamina, ear rhachis, glume, palea, flower and caryopsis of 46Triticum andAegilops species were examined on the basis of coloured sections, made by hand or by microtome. Due to the smaller organ sizes ofAegilops also the cell sizes are mostly reduced in this genus. Often distinct character proved to be correlated with distinct ploidy levels. In some instances we were able to find a clear influence of distinct species or genomes on the characters of their alloploid taxa, e. g. an influence ofAegilops tauschii on the characters of the hexaploid wheat species and on the remaining species of sectionVertebrata ofAegilops. We found characters in all organs which point to a connection betweenTriticum species with genome G and the diploid wheats. The degree of similiarity to the other wheat species is much less strongly. One anatomical character of the culm indicates even a possible contribution ofTriticum urartu to the evolution of the wheat species with genome G. Most of the tetraploid species ofTriticum, genome AB, can be arranged into two different groups by means of leaf and glume characters. The diploid wheat species are a well characterized group. We were not able to find real anatomical differences between wild and cultivated wheat species besides the brittle ear rhachis. Within the genusAegilops the species of the sectionsSitopsis andAmblyopyrum resemble one another and theTriticum species much more than the other species ofAegilops. By anatomical characters it is not possible to indicate exactly the donor of genome B. Characters, which can be found only one time within the genera studied, are very seldom, but rather isolated species occur in several groups. Many anatomical characters are so variable even within the same species, that these characters can not be evaluated in phylogenetic respect.

- Triticum L. Aegilops L. (Gramineae)
46 Triticum Aegilops , , , , , . Aegilops . , . ; Aegilops tauschii Vertebrata Aegilops. Triticum , G, , . Triticum urartu , G. Triticum, AB, . , . . Aegilops Sitopsis Amblyopyrum; Triticum, . - , , . , Tritcum Aegilops — , , , . , .


Herrn Prof. Dr. Drs. h. c.Hans Stubbe zum 75. Geburtstag gewidmet.  相似文献   
86.
Summary Important papers on taxonomy and evolution of cultivated plants published in 1986 and 1987 were compiled and briefly discussed.
Taxonomic und Evolution der Kulturpflanzen: Litcraturübersicht 1986/1987
Zusammenfassung Wichtige Arbciton übot Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1986 und 1987 wuzden zusammengestolit und kurz kommentiert.

: . 1986–1987
, 1986 1987 . .
  相似文献   
87.
The study was carried out on 3 groups of 10 fish, each fed on a different natural labelled food. The preys selected were a crustacean (Gammarus pulex), a midge larvae (Chironomus sp.) and the soft tissues from a snail (Lymnaea stagnalis), which are usually consumed by carp in the natural environment. The contaminated food consumption by the fish resulted in a 60Co maximum transfer factor ranging from 1.2 × 10?2 to 5.1 × 10?2 depending on the food type. These values, and the contamination kinetics indicate that the biomagnification of the radionuclides cannot occur, even over the long term. 60Co depuration from fish was also influenced by the contaminated food type, previously ingested. The lower elimination rate correspond to the higher value of the transfer factor (Gammarus pulex) and inversely (Lymnaea stagnalis).  相似文献   
88.
The permeability of plastic films to the fumigant methyl bromide (MB) was measured by two different methods, in order to facilitate the selection of films which are impermeable to the gas. Polyethylene-based films are highly permeable to MB, as evidenced by both methods. In contrast, multilayer coextruded films which have a layer of barrier material such as polyamide (PA) or ethylene-vinyl alcohol copolymer (EVOH) were significantly less permeable to MB, as reflected by the parameters permeability rate, time to 90% concentration (TC90, by the diffusion method) and lag-time values (by the variable-volume method). A significant correlation was found between the permeability rate assessed by the diffusion method and that obtained with the variable-volume method. Permeability of all films increased with temperature as evidenced by all tested parameters. This increase was more pronounced with polyethylene films, the permeabilities of which increased five- to six-fold when the temperature was increased from 20°C to 60°C. The effect of temperature on barrier-film permeability was less significant. Permeability of films to MB was affected by additional factors such as additives, the length of the monomer side-chain, and the thickness and density of polyethylene films. © 1998 SCI  相似文献   
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