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101.
102.
103.
Summary Potato (Solanum tuberosum L.) cultivars were grown in pots and containers under a rain shelter to examine differences in stomatal conductance, water-use
efficiency, and carbon isotope fractionation. Conductance was measured on abaxial leaf surfaces with a steady state diffusion
porometer. Carbon isotopic analyses were made with an isotope ratio mass spectrometer. Water-use efficiency (WUE) was obtained
by dividing total dry matter production by cumulative transpiration.
Significant genetic variation was observed for each trait. WUE was positively related to carbon isotope fractionation (13∈) and was inversely related to stomatal conductance. Carbon isotope analysis and porometry show potential as indirect screening
methods to identify genetic differences in water-use efficiency. 相似文献
104.
L. A. van Leengoed J. Vos E. Gruys P. Rondhuis A. Brand 《The Veterinary quarterly》2013,33(3):131-141
In a commercial swine herd a rise was noted during the summer of 1981 in the number of repeat breeders, mostly four to eight weeks after serving. During the autumn there was a decrease in the litter size at birth and an increase in the number of stillborn and mummified piglets. Several gilts and sows showed a seroconversion against Porcine Parvovirus (PPV), determined by the Haemagglutination Inhibition lest (HI‐test). Characteristic pathological findings were seen in some maturely stillborn and neonatally deceased piglets (up to an age of 28 days); hepatic congestion and necrosis, accummulation of fluid in body cavities, myocarditis, and encephalitis were the most Prominent features. Serological tests for antibodies in blood samples of one sow and body fluids of two stillborn piglets were suggestive of Porcine Parvovirus as the aetiological agent. 相似文献
105.
G. J. Binkhorst D. L. H. Journée W. Wouda P. J. Strayer J. H. Vos 《The Veterinary quarterly》2013,33(4):145-155
The clinical and pathological findings after a natural intra‐uterine infection with BVD‐virus in a Friesian dairy herd are described. The virological and serological aspects will be discussed in a separate paper (30). In a period of 4 years, 11 calves were hum with the following nervous symptoms: more or less serious incoördination, tremor, oscillating nystagmus, and a negative blinking reflex. The pupillary and sucking reflexe's were normal. No ocular defects, such as lenticular opacity or retinal atrophy were observed. The first calf was born in 1979. Within 6 months the symptoms disappeared. After a normal conception and pregnancy this animal gave birth to 2 clinically normal calves in 1981 and 1982. The second calf died at the age of 2 months, due to an ulcerating enteritis. In 1980, again 8 calves with the same nervous symptoms were born within a period of 3 months. Two calves died at the age of 3 days and 5 weeks respectively; 2 calves were sold when 10 days and 3 weeks old; one calf did not improve and was necropsied at the age of 17 days. The remaining 3 calves showed only a slight hypermetria when examined after 6 months. At that time nystagmus was only visible with ophthalmoscopy. Two calves were slaughtered when 10 months old. The last one, a bull, proved to be sterile and was necropsied at the age of 1 ½> year. A calf, born in 1981, recovered within a week and was necropsied at the age of 15 days. The last calf, born in 1982, did not improve at all and was necropsied at the age of 14 days. During these 4 years none of the other animals in the herd showed any symptoms due to an acute or chronic BVD‐virus infection. At post mortem examination of 6 animals no macroscopically visible malformations were found. Hypomyelination and abnormal glial cells were evident in 5 cases, especially in the two youngest calves which did not show any improvement. One of them had an obvious thymic hypoplasia. The calf which recovered within a week showed only very slight changes. In one of the calves slaughtered at 10 months, inflammatory lesions were found in the brain. The diagnosis was confirmed by virological investigations. Clinically as well as pathologically there was a close resemblance to Border disease in lambs and congenital tremor in piglets after prenatal exposure to Hog cholera virus. 相似文献
106.
Summary The results of the cytological and histological examination of 348 canine lesions, localised in various organs, were compared with respect to the tumourous or non‐tumour nature of the lesions and the malignancy or benignancy of tumours. The retrieval rate was 92.5%. Regarding the distinction between tumourous and non‐tumourous lesions, the cytological examination showed a diagnostic accuracy of 83.9%, a sensitivity of 95.6%, a specificity of 65.4% and a predictive value for the presence of tumour of 93.5%. The diagnostic accuracy of cytology concerning the differentiation in malignancy and benignancy of the neoplasms was 83.7%, with a sensitivity of 86.8%, a specificity of 79.4% and a predictive value for the presence of malignant tumour of 85.6%. These results confirm the value of non‐exfoliative cytology as a diagnostic method, providing rapid and valuable information with regard to diagnosis and prognosis and, consequently, for therapeutic handling. An eventual histological diagnosis remains indicated, especially in case of soft‐tissue and mammary lesions. 相似文献
107.
J.H. Vos T.S.G.A.M. van den Ingh W. Misdorp R.F. Molenbeek F.N. van Mil G.R. Rutteman 《The Veterinary quarterly》2013,33(3):89-95
Summary Duct ectasias (n=2) and different types of benign canine mammary tumours (n=19) were studied immunohistochemically with monoclonal antibodies (MoAbs) directed against various human keratin types (K), α‐smooth muscle actin, vimentin, and desmin. In the duct ectasias and in most tumours the epithelial structures revealed an inner and outer cell layer. The inner cell layer was characterized by labelling with K 7, 8, 18, 19 and mostly also with K 4 and/or K 10 MoAbs. The outer cell layer was almost invariably labelled by K 14, K 14 and 17, and a‐smooth muscle actin MoAbs. The labelling patterns of both duct ectasias and tumours corresponded largely to the patterns observed in normal mammary gland tissue, although a more distinct heterogeneity was seen. Tumours histomorphologically assumed to be of a myoepithelial origin did not show immunohistochemical features of myoepithelial cells. The myoepithelial nature of the vast majority of spindle‐shaped cells present in the adenomas of the complex type and in the fibroadenomas of the benign mixed type could not be confirmed immunohistochemically. These cells, however, unequivocally expressed vimentin, suggesting proliferation of stromal cells in these tumours, which in the fibroadenomas of the benign mixed type may show metaplasia to bone or cartilage. In the duct ectasias and in some tumours, a fraction of elongated stromal cells, probably representing myofibroblasts, was labelled with the α‐smooth muscle actin MoAb. 相似文献
108.
109.
Libor Mrnka Michal Kuchár Zuzana Cieslarová Pavel Matějka Jiřina Száková Pavel Tlustoš Miroslav Vosátka 《Water, air, and soil pollution》2012,223(1):399-410
There is increasing interest in poplars and willows due to their biomass production and phytoremediation potential. They host
two major types of mycorrhizal fungi that can substantially modulate the physiology of their hosts. In this study, the effects
of endo- and ectomycorrhizal fungi on growth, physiological parameters, and heavy metals accumulation were studied in a pot
experiment using Salix alba L. and Populus nigra L. The mycorrhizal fungi were inoculated separately and in combination to a soil substrate polluted by a mixture of heavy
metals (mainly Cd, Pb, and Zn). Tree species differed in their mycorrhizal affinities, with poplar being colonized predominantly
by Glomus intraradices and willow by Hebeloma mesophaeum. H. mesophaeum increased willow height and biomass, while G. intraradices decreased poplar height. The photosynthetic rate remained unchanged, and only minor changes were observed in the relative
composition of photosynthetic pigments. Poplar photosynthetic rates and levels of photosynthetic pigments declined, while
the epicuticular waxes in leaves increased toward the end of the experiment, irrespective of the inoculation. H. mesophaeum strongly reduced the accumulation of Cd and Fe in willow and poplar shoots, respectively. Our results support the use of
selected mycorrhizal strains to tune phytoremediation outcomes in their plant hosts. 相似文献
110.
Nitrogen Responses and Nitrogen Management in Potato 总被引:2,自引:0,他引:2
J. Vos 《Potato Research》2009,52(4):305-317
Innumerable experiments have been carried out to establish the yield response of potato to the rate of nitrogen (N) supply.
Given the continuing change in production level of potato and because of the need to maximise the nutrient use efficiency
and to reduce losses of harmful nitrogenous compounds to the environment, such research is still necessary and topical. This
minireview addresses dose–response curves of fertiliser N input; the development of N fertiliser recommendation systems; the
so-called three-quadrant diagram of fertiliser N response which dissects the ‘agronomic response’ into the underlying components;
the concept of critical nitrogen concentration as a function of crop biomass; environmental aspects of fertiliser nitrogen
supply; and the strategy of the potato plant to cope with nitrogen limitation. European legislation sets limits on the input
of nitrogen and sets norms on water quality, making nitrogen use efficiency (NUE) a critical issue. Precision agriculture
may help to maximise NUE, provided an adequate diagnostic system is developed that distinguishes between nitrogen deficiency
and other causes of spatially divergent crop performance. 相似文献