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71.
Reiner G Hillen S von Berg S Kixmöller M Willems H 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(5-6):236-241
Lawsonia (L.) intracellularis, Brachyspira (B.) hyodysenteriae and B. pilosicoli are important pathogens in domestic pig production world-wide, responsible for porcine intestinal adenomatosis, swine dysentery, and porcine intestinal spirochetosis, respectively. Conventional PCR is the major diagnostic tool in the detection of the three pathogens, but the sole detection of bacterial DNA might lead to misinterpretations of results with respect to their clinical relevance, especially with mixed infections. Thus, the present study targeted the detection and quantification of the three pathogens in samples from herds with a case history of diarrhoea. Herds and samples were selected by the practitioners on a voluntary basis. Results were based on 1176 individual samples from 95 herds from Southern Germany. The pathogens were detected simultaneously by multiplex real-time PCR. The overall prevalence for L. intracellularis, B. hyodysenteriae and B. pilosicoli was 12.6%, 8.4% and 3.2% in faecal samples and 48.4%, 24.2% and 31.6% in herds, respectively. Sixty one percent, 82.6%, and 73.4% of herds positive for L. intracellularis, B. hyodysenteriae, and B. pilosicoli, respectively, had mixed infections. Median log values of DNA equivalents/g of faeces for L. intracellularis, B. hyodysenteriae and B. pilosicoli were 3.3, 5.9 and 3.2, with maxima of 8.3, 8.0 and 6.3, respectively. Within herd prevalence of B. hyodysenteriae and B. pilosicoli as well as the load of B. hyodysenteriae were significantly associated with the severity of diarrhoea. 相似文献
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74.
Talaat El Sebaï Marion Devers-Lamrani Bernard Lagacherie Nadine Rouard Guy Soulas Fabrice Martin-Laurent 《Biology and Fertility of Soils》2011,47(4):427-435
The impact of soil moisture content and temperature on isoproturon (3-(4-isopropylphenyl)-1,1-dimethyl-urea [IPU]) mineralization
activity was assessed on an agricultural soil regularly exposed to this herbicide. Mineralization of 14C-IPU was monitored on soil microcosms incubated at different temperatures (10°C, 20°C, 28°C) and soil moisture contents (9%,
12%, 15, 18%, 21%, 24%). An increase in temperature and/or soil moisture significantly enhanced the maximum rate and percentage
of IPU mineralization while it decreased the lag time before mineralization. The maximum rate and percentage of IPU mineralization
respectively ranged from 0.18% day−1 and 9% for the lowest temperature and soil moisture content pair (10°C–9%) to 1.51% day−1 and 27.1% for the highest pair (28°C–24%). Statistics revealed a cross interaction of temperature and soil moisture content
on the maximum rate of IPU mineralization. The optimum conditions for IPU mineralization, estimated from the double Gaussian
model, were 25.8°C and 24% soil moisture content. The influence of fluctuations in soil moisture content on IPU-mineralization
was investigated by subjecting the soil microcosms to drought stress. When IPU was added at the end of the drought stress,
it had no statistical effect on IPU mineralization. However, when it was added before the drought stress, two mineralization
phases were observed: (1) one corresponding to the drought stress for which mineralization was low and (2) another one observed
after restoration of soil moisture content characterized by higher mineralization rate. It can be concluded that climatic
fluctuations affect the activity of IPU mineralizing microbial community, and may lead to an increase in IPU persistence. 相似文献
75.
76.
Jemanesh K. Haile Karl Hammer Ayele Badebo Miloudi M. Nachit Marion S. Röder 《Genetic Resources and Crop Evolution》2013,60(2):513-527
A set of 77 markers was used to describe the genetic diversity in a group of 58 tetraploid wheat accessions. Analysis was performed using 31 neutral SSR markers, 31 SSR/STS markers linked with reported major stem rust resistance genes and 15 SSR markers linked with QTL identified for resistance to Ethiopian stem rust races of Puccinia graminis Pers. f. sp. tritici Eriks. et E. Henn. (Pgt),including Ug99. The material consisted of 32 (Triticum durum s.l. incl. T. aethiopicum Jakubz., Triticum turgidum and Triticum polonicum) landraces and 22 registered T. durum varieties from Ethiopia that were released 1966–2009 and four T. durum varieties from ICARDA. A total of 720 alleles were detected. Considering the three marker sets, the mean number of alleles was higher for major stem rust resistance gene linked markers (9.9) followed by neutral SSR markers (9.2) and markers linked with QTL for stem rust resistance (8.5). Dendrograms derived from UPGMA analysis grouped the accessions into two major clusters. The principal component analysis based on the combination of the three marker sets formed three groups. The 1st group was composed of all the improved varieties, whereas the 2nd and the 3rd group contained the landraces. All the landraces that formed the 3rd group were susceptible to Ethiopian stem rust races of Pgt including Ug99. The information on the extent of the genetic diversity of the improved varieties obtained in this investigation will be helpful for developing appropriate breeding strategies to broadening the genetic base of durum wheat varieties in further breeding programmes. 相似文献
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Franziska Löschenberger Andreas Fleck Heinrich Grausgruber Herbert Hetzendorfer Gerhard Hof Julia Lafferty Marion Marn Anton Neumayer Georg Pfaffinger Johann Birschitzky 《Euphytica》2008,163(3):469-480
Breeding for organic agriculture (BFOA) is a strategy for a commercial breeding company based on the exploitation of the frequently
observed high correlation for many traits between conventional, low input (LI) and organic agriculture (ORG). Indirect selection
under LI can be useful to roughly divide the germplasm into the genotypes better adapted to high input and those better adapted
to LI or ORG conditions. BFOA is an evolving process, in which two methods are currently applied: early generations are either
selected following the pedigree system under LI, or grown as bulk populations on ORG fields. In the latter case the system
switches to LI after individual ear selection under ORG conditions. In both methods, the first replicated yield trial is grown
parallel under ORG and LI. Subsequently, the genotypes are grouped into conventional or ORG advanced trial series. The BFOA
strategy allows that the larger genetic variability of both the organic and conventional gene pool can be exploited in the
selection for ORG. Hitherto, seven winter wheat varieties were released in Austria after exclusive organic VCU testing. 相似文献
79.
80.
Franziska R. Haunhorst Klaus Hopster Marion Schmicke Astrid Bienert-Zeit Sabine Kstner 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(1):39
The objective of this study was to compare effects of butorphanol (BUT) or buprenorphine (BUP), in combination with detomidine and diazepam, on the sedation quality, surgical conditions, and postoperative pain control after cheek tooth extraction in horses, randomly allocated to 2 treatment groups (BUT: n = 20; BUP: n = 20). A bolus of detomidine (15 μg/kg, IV) was followed by either BUP (7.5 μg/kg, IV) or BUT (0.05 mg/kg, IV). After 20 min, diazepam (0.01 mg/kg, IV) was administered and sedation was maintained with a detomidine IV infusion (20 μg/kg/h), with rate adjusted based on scores to 5 variables. All horses received a nerve block (maxillary or mandibular), and gingival infiltration with mepivacaine. Sedation quality was assessed by the surgeon from 1 (excellent) to 10 (surgery not feasible). A pain scoring system (EQUUS-FAP) was used to assess postoperative pain. Serum cortisol concentrations and locomotor activity (pedometers) were measured.Horses in BUP and BUT required a median detomidine infusion rate of 30.2 μg/kg/h (20 to 74.4 μg/kg/h) and 32.2 μg/kg/h (20 to 48.1 μg/kg/h), respectively (P = 0.22). Horses in the BUP group had better sedation quality (P < 0.05) during surgery and higher step counts (P < 0.001) postoperatively. Buprenorphine combined with detomidine provided a more reliable sedation than butorphanol. However, the EQUUS-FAP pain scale became unreliable because of BUP-induced excitement behavior. 相似文献