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981.
Lead poisoning in cattle: brain lesions and hematologic changes 总被引:4,自引:0,他引:4
982.
983.
984.
Christian Horstmann 《Genetic Resources and Crop Evolution》1962,10(1):132-139
Zusammenfassung Für die kolorimetrische Bestimmung von Khellin und Visnagin ausAmmi visnaga L. wird eine empfindliche Farbreaktion beschrieben, die auf der Bildung eines blauvioletten Farbstoffs aus den Furanochromonen undm-Dinitrobenzol in stark alkalischer Lösung beruht. Die Empfindlichkeit der Methode reicht aus, um beide Verbindungen nach papierchromatographischer Trennung quantitativ zu bestimmen. Die gleiche Reaktion eignet sich für die Sichtbarmachung von Khellin und Visnagin auf dem Papierchromatogramm.
Summary A sensitive colour reaction is described for the colorimetrio estimation of khellin and visnagin fromAmmi visnaga Linn., depending on the formation of a blue-violet dye from the furochromones andm-dinitrobenzene in a strongly alkaline solution. The sensitivity of this method is sufficient to estimate both the compounds after paperchromatographic separation. The same reaction is suitable for the detection of khellin and visnagin on paperchromatograms.
Ammi visnaga L. - m- . . , .相似文献
985.
Comparative studies with three different bovine blood sample BHV-1 ELISA tests: indirect ELISA and bG-blocking-ELISA 总被引:3,自引:0,他引:3
A total of 2754 bovine blood samples were examined for BHV1 antibodies in three different BHV-1 ELISA tests. The tests used were the CHEKIT Trachitest 2nd. Gen. "Best?tigungstest" Serum, the CHEKIT-BHV-1-gB-ELISA (Bommeli-Diagnostics/Intervet), and the BHV-1-gB Antibody Test Kit (IDEXX). A first testing identified 111 (4.0%) of the samples as positive and 2501 (90.8%) samples negative in all three tests. Onehundredand-fortytwo (5.2%) of the samples showed a not negative result in at least one of the two gB-ELISAs. The testing was repeated for 139 of the 142 samples and still 89 (3.2%) samples were found with discrepant results. The remaining 50 samples showed a negative reaction in the three ELISA tests. After Western blot analysis antibodies against glycoprotein B (gB) of BHV-1 were only detected in 11 of the 89 samples with a not negative reaction in at least one of the gB-ELISAs. Three of the 50 ELISA-negative samples showed a positive reaction in the Western blot. The high number of positive results in the gB-ELISAs which were negative in the Western blot assay leads to the conclusion that gB-ELISAs may have a lower specificity as the indirect ELISA. Introducing the gB-ELISA as the standard test for BHV1 serology in Bavaria would result to an increase of the number of BHV-1 positive farms by 8% (gB IDEXX) or 20% (gB Bommeli) 20%. 相似文献
986.
Until recently, epidemiological studies on Bovine Spongiform Encephalopathy (BSE) were based on Mandatory Reporting Systems (MRS) of clinically suspect bovines only, but rapid diagnostic tests were validated in 1999 and are used for targeted surveillance in Switzerland, France and other countries, as a complementary and secondary tool. Data on 30491 cattle issued from a French pilot program targeted at cattle having died on the farm, subjected to euthanasia or sent for emergency slaughter, did not show any significant difference in BSE risk between dairy and beef suckler breeds. The data also revealed that part of the clinical cases of BSE escaped the MRS, which permitted to detect more dairy than beef suckler affected cattle compared to the targeted surveillance in the same period (from August to December 2000) and region (Bretagne, Pays de la Loire and Basse Normandie regions). Analyzing together the data of the targeted surveillance and mandatory reporting system programs with a non-conditional logistic regression, we found that the odds of a dead cow being a BSE case among all dead cattle was 3.2 times higher for dairy breeds compared to beef suckler breeds. This confirmed British findings but points out to the fact that considering either MRS or targeted surveillance data alone may possibly create biases in epidemiological studies on BSE. 相似文献
987.
Infection of goats by caprine arthritis-encephalitis virus (CAEV) provides a convenient example of the infiltration of various tissues by leukocytes following a natural lentiviral infection. This event is important in determining organ susceptibility and local immunity. Caprine vascular endothelial cells are susceptible to infection by CAEV in vitro, so we have investigated the consequences of this infection on the transmigration of uninfected leukocytes in an in vitro model. After in vitro infection by CAEV or stimulation by TNFalpha, the endothelial cells allowed the passage of tenfold more leukocytes from uninfected donors than did the uninfected endothelial cells. The transmigrating leukocytes were enriched in CD8+ lymphocytes, and the leukocytes appeared to have been activated during transmigration, as demonstrated by their expression of IL2R, MHC class II antigens and gamma-delta T-lymphocyte markers. CD4+, CD8+ and B-lymphocytes all proliferated in culture after transmigration. These results suggest that any possible infection or specific stimulation of endothelia in an infected animal could profoundly influence the choice of target organs and could activate the cells involved in local mucosal immune responses. 相似文献
988.
The spatial heterogeneity of Bovine Spongiform Encephalopathy (BSE) was analysed on the 84 cases confirmed in western France (WF) between August and December 2000, when both the Mandatory Reporting System and an active surveillance on cattle at risk were running. Ninety-four percent of these cases were born between June 1993 and June 1996, and we analysed the location at birth. One disease mapping and two clustering methods (Scan of Kulldorff and the method of Besag and Newell) were used. In order to attenuate the contrasts artificially created by the standard disease mapping method (over-dispersion), we estimated the Standard Incidence Ratio (SIR) with a Bayesian method (Poisson-Gamma model) allowing a smoothing of the estimators. The geographical location of interest was the "canton", that divided the total area into 526 geographical units. The background population (2.6 million cattle) was obtained from the Agricultural Census 2000. We tested the hypothesis of a homogenous spatial distribution of the BSE risk where the expected number of BSE cases per unit area was obtained by applying the overall BSE rate in WF to each "canton", standardised on the type of breed, dairy versus beef suckler. The SIR ranged from 0.80 to 2.18 and the spatial distribution of BSE cases was significantly heterogeneous. Two spatial clusters were detected with the spatial scan statistics of Kulldorff and the method of Besag and Newell (18 to 20 observed BSE-cases per cluster with a radius of 45 km) centred on the "département" of C?tes-d'Armor and Mayenne. Another cluster was detected with the method of Besag and Newell (9 observed BSE-cases) in the "département" of Finistère. The results proved that the risk of BSE is linked to the geographical location in the area of the study. 相似文献
989.
Danile Debieu Jocelyne Bach Mickael Hugon Christian Malosse Pierre Leroux 《Pest management science》2001,57(11):1060-1067
Fenhexamid, a recently developed botryticide, is shown here to inhibit sterol biosynthesis. When the fungus Botryotinia fuckeliana was grown in the presence of fenhexamid, the ergosterol content was reduced, and three 3‐keto compounds, 4α‐methylfecosterone, fecosterone and episterone, accumulated, suggesting an inhibition of the 3‐keto reductase involved in C‐4 demethylation. Thus, fenhexamid belongs to a new, promising class of sterol biosynthesis inhibitors not previously used in agriculture or in medicine. © 2001 Society of Chemical Industry 相似文献
990.
Christoph Lüthy Helmut Zondler Thomas Rapold Gottfried Seifert Bernhard Urwyler Thomas Heinis Hans Christian Steinrücken James Allen 《Pest management science》2001,57(3):205-224
A series of novel types of 7‐(4,6‐dimethoxypyrimidin‐2‐yl)oxy ‐ and ‐thio‐3‐methyl‐1 (3H)‐isobenzofuranones were discovered at Dr R Maag AG. From the thio‐isobenzofuranyl series, CGA 279 233—BSI‐proposed common name pyriftalid—was chosen for further development as a grass herbicide for use in rice. General synthetic approaches to these new phthalic acid‐derived compounds are given, with emphasis on the synthesis of pyriftalid and its physico‐chemical behaviour. © 2001 Society of Chemical Industry 相似文献