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991.
Luvoni GC Tessaro I Apparício M Ruggeri E Luciano AM Modina SC 《Reproduction in domestic animals》2012,47(3):385-391
Cryopreservation of ovarian cortex has important implications in the preservation of fertility and biodiversity in animal species. Slow freezing of cat ovarian tissue resulted in the preservation of follicular morphology and in the follicular development after xenografting. Vitrification has been recently applied to ovarian tissues of different species, but no information is available on the effect of this method on feline ovarian cortex. Moreover, meiotic competence of fully grown oocytes isolated from cryopreserved tissue has not been reported. The aim of this study was to evaluate the effect of vitrification of feline ovarian cortex on follicular morphology and oocyte integrity, as well as meiotic competence. A total of 352 fragments (1.5-2 mm(3) ) were obtained from ovarian cortical tissues: 176 were vitrified and 176 were used fresh as control. Histological evaluation of fresh and vitrified fragments showed intact follicles after cryopreservation procedures with no statistically significant destructive effect from primordial to antral follicles. After IVM, oocytes collected from vitrified ovarian fragment showed a higher proportion of gametes arrested at germinal vesicle (GV) stage compared to those isolated from fresh control tissue (33.8% vs 2.9%; p < 0.001). However, oocytes isolated from vitrified tissues were able to resume meiosis, albeit at lower rate than those collected from fresh tissues (39.8% vs 85.9%; p < 0.00001). Vitrification induced changes in the organization of cytoskeletal elements (actin microfilaments and microtubules) of oocytes, but significantly only for actin network (p < 0.001). Finally, chromatin configuration within the GV was not affected by the cryopreservation procedure. Our study demonstrated that vitrification preserves the integrity of ovarian follicles and that oocytes retrieved from cryopreserved tissue maintain the capability of resuming meiosis. To our knowledge, this has not previously been reported in the cat. 相似文献
992.
Zhang L Franchini M Wehrli Eser M Jackson EK Dip R 《Veterinary journal (London, England : 1997)》2012,193(1):268-270
Several reports have suggested a role for adenosine in the pathogenesis of chronic airway conditions and this has led to new therapeutic strategies to limit airway inflammation. In this study, detectable levels of adenosine in bronchoalveolar lavage (BAL) samples from 11 horses with non-infectious lower-airway inflammation and 14 healthy controls are reported, with significantly higher values in horses with airway inflammation. Although these increased levels did not correlate with changes in neutrophil percentage in BAL, a positive association between adenosine levels and signs of lower airway inflammation (clinical score) was observed. These novel findings support the hypothesis that adenosine may contribute to bronchoconstriction and also act as a pro-inflammatory mediator in the bronchoalveolar milieu of horses with airway inflammation. Further investigation of this axis could lead to new approaches for the treatment of highly prevalent lower airway inflammatory conditions in the horse. 相似文献
993.
Whittaker AG Love S Parkin TD Duz M Cathcart M Hughes KJ 《Veterinary journal (London, England : 1997)》2012,191(2):208-212
The pH measurement of exhaled breath condensate (EBC) may provide a non-invasive method of assessing the lower airways of horses but the methodology used may influence findings. The aim of this study was to investigate the effect of two sampling devices and three methods of condensation surface cooling (ethanol slush, -100°C; dry ice, -75°C; water ice, 0°C) on EBC pH. Each method was tested 30 times using six healthy ponies. Sample pH was determined before and after de-aeration with argon for 10 min. Sampler design was found to significantly affect pH. Samples collected as a liquid had a significantly higher pH than samples frozen during collection (P<0.05). De-aeration resulted in significantly higher pH (P<0.05) with less variation. This study has shown that device design and condensation surface temperature will influence EBC pH, which will prevent a direct comparison of results when different methodologies are used. 相似文献
994.
Lamagna B Peruccio C Guardascione A Paciello O Costagliola A Giudice C Rondena M Saccone M Uccello V Lamagna F 《Veterinary ophthalmology》2012,15(3):194-199
Two 5-month-old golden retriever dogs were referred for the evaluation of a mass arising from the left ventrolateral conjunctiva of the lower eyelid. The masses were externally located, deemed to be cystic in nature, and were surgically removed, and in one case, 0.15 mL of clear fluid was collected. Cytological examination of the aspirated fluid revealed proteinaceous, basophilic amorphous material, and few epithelial cells with foamy cytoplasm and small nuclei. No micro-organisms were detected. Histological examination of the cysts showed a wall composed of single to double cell layers. The cells were cuboidal to flattened, nonciliated, lined with mild submucosal connective tissues and slight inflammation composed of lymphocytes, plasma cells, and rare macrophages. In some areas, lobules of acinar glandular tissue were observed. To the authors' knowledge, this is the first case report of conjunctival dacryops in dogs. The complete surgical removal of the cysts was curative in both cases. 相似文献
995.
996.
Laura Armenise Marco C. Simeone Roberta Piredda Bartolomeo Schirone 《European Journal of Forest Research》2012,131(5):1337-1353
DNA barcoding may be particularly important in impacting the current trends of world’s biodiversity crisis, public economic issues and science. Forests play a crucial role in self-sustaining natural ecosystems and human environment at both local and regional scales. Over 39% of the world’s forests are formed by conifers; most species are highly exposed to threats and exploited at high frequency. Conifers have an urgent need to be identified through DNA barcodes, but received little attention up to date. The application of standard barcoding protocols appears to be hampered by a lack of consensus on the selection of markers and low rates of successful species identification. We examined whether four marker regions (trnh-psba, rbcL, rpoc1 and matK) matched conifer species taxonomy in a practical biodiversity survey of Italian forested land. Our objective was to provide a test of future in situ applications of DNA barcodes by evaluating the efficacy of species discrimination under the criteria of uniformity of methods and natural co-occurrence of the species. Twenty-five conifer species were included in a floristic study based on regional samplings. Genetic distance, similarity and phylogeny approaches were used to assess identification of taxa and species monophyly. We obtained 100% total discrimination success, with rbcL?+?trnH-psbA as the suggested two-locus barcode in terms of universality and efficacy. Consistent barcoding gaps, supported monophyly and regional patterns of diversity, were evidenced. Species requiring further investigation to be fully assessed at a broader context are indicated. We conclude that the time seems now ripe for coherent barcoding campaigns of entire forest tree regional floras. 相似文献
997.
Peletto S Zuccon F Pitti M Gobbi E Marco LD Caramelli M Masoero L Acutis PL 《Research in veterinary science》2012,92(1):147-150
Recently, atypical bovine pestiviruses (BVDV-3) have been identified in batches of contaminated foetal calf serum (FCS) and in naturally infected cattle. During routine screening of FCS by conventional panpestivirus PCR assay, one batch showed traces of pestivirus nucleic acids, and the contaminating virus was typed as BVDV-3-like. Phylogenetic analysis based on three genome regions (5'UTR, N(pro) and E2) showed that this strain, named IZSPLV_To, clusters in a separate clade with CH_KaHo/cont, a cell culture contaminant detected in Switzerland. This study is the first report of the detection in Italy of a FCS batch contaminated with BVDV-3 and adds more evidence that atypical pestiviruses represent a serious cause for concern in cell culture laboratories, with potential repercussions on BVD control and vaccine biosafety. Our findings suggest that the BE/B2 primers may be able to detect BVDV-3 in a panpestivirus assay, but testing of a larger number of strains is required. 相似文献
998.
Marco Pautasso Thomas F. D?ring Matteo Garbelotto Lorenzo Pellis Mike J. Jeger 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):295-313
There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases. This
overview addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends
in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study:
Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied
by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and
pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change
on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect
effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate
change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement
of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing
vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical
regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of
plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various
plant disease control methods. 相似文献
999.
Toncian T Borghesi M Fuchs J d'Humières E Antici P Audebert P Brambrink E Cecchetti CA Pipahl A Romagnani L Willi O 《Science (New York, N.Y.)》2006,312(5772):410-413
We present a technique for simultaneous focusing and energy selection of high-current, mega-electron volt proton beams with the use of radial, transient electric fields (10(7) to 10(10) volts per meter) triggered on the inner walls of a hollow microcylinder by an intense subpicosecond laser pulse. Because of the transient nature of the focusing fields, the proposed method allows selection of a desired range out of the spectrum of the polyenergetic proton beam. This technique addresses current drawbacks of laser-accelerated proton beams, such as their broad spectrum and divergence at the source. 相似文献
1000.
Paola Cordiali-Fei Elisabetta Trento Giovanna D'Agosto Valentina Bordignon Anna Mussi Marco Ardigò Antonio Mastroianni Antonella Vento Francesco Solivetti Enzo Berardesca Fabrizio Ensoli 《Journal of Autoimmune Diseases》2006,3(1):5