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991.
992.
Inhalt Von 5 Besamungsebern wurde in 4 zeitlich auseinanderliegenden Kombinationen Disperma zum Zwecke eines Fertilitdtstestes eingesetzt. In 2 der 4 Kombinationen wies der disperme Befruchtungstest eine erhebliche Diskrepanz zur parallel monosperm durchgeführten Fertilitätsprüfung auf. Für 2 Eber (Eber B and C) ergaben 2 verschiedene disperme Tests widersprüchliche Fruchtbarkeitswerte. Die disperme Insemination zum Zwecke eines Fertilitätstestes ist somit unbrauchbar. Contents Studies on the suitability of disperm for testing the fertility of A. I. boars. Disperm from 5 A. I. boars was used in four time combinations to test the fertility of these boars. In two of the four combinations the dispermic fertility test showed a considerable discrepancy with the fertility test made simultaneously with monosperm. For boars B and C, two different dispermic tests gave contradictory fertility results. Dispermic insemination is thus unsuitable for fertility tests. 相似文献
993.
994.
F. D. Meyer K. Gyr L. Kayasseh W. W. Rittmann G. A. Stalder J. Girard 《Veterinary research communications》1980,4(1):145-150
Small doses of caerulein (10, 20, 40, 100 ng/kg/h) were given to conscious dogs with chronic duodenal and gastric fistulas, and the exocrine pancreatic response was compared with that obtained by a testmeal. Maximal protein and bicarbonate secretion varied between 20 and more than 100 ng/kg/h, depending on the individual animal. Testmeal-stimulated pancreatic secretion was approximately equivalent to that achieved with 10 ng caerulein/kg/h. Plasma secretin levels did not change significantly during testmeal stimulation. 相似文献
995.
Sugar beet plants were grown in the field, after in-furrow application of [14C]aldicarb (3 kg of aldicarb ha?1) at planting. Some plants (the growing plants) were harvested 99 days after sowing and the rest (the ripe plants) 196 days after sowing. The percentages of the weights of [14C]aldicarb equivalents (the total aldicarb plus aldicarb sulphoxide and sulphone, plus all the other metabolites of [14C]aldicarb which contain 14C, expressed as aldicarb equivalents) incorporated into the beet plants, relative to the weight applied to the soil, were 2.8 and 1.8, respectively for the growing and ripe plants. The concentrations of [14C]aldicarb equivalents (mg kg?1 fresh weight) in the growing and ripe plants, respectively were: blades of the external leaves, 3.16 and 0.93; blades of the internal leaves, 0.63 and 0.68; petioles of the external leaves, 0.51 and 0.26; petioles of the internal leaves, 0.15 and 0.05; crowns, 0.14 and 0.15; roots, 0.16 and 0.13. The proportions of the extractable aldicarb plus aldicarb sulphoxide and aldicarb sulphone determined by gas-liquid chromatography (expressed as aldicarb equivalents) relative to [14C]aldicarb equivalents, in the external and internal leaf blades of the growing beets, were 56 and 60%, respectively; these values declined to 25 and 19%, respectively in the ripe plants. The proportion was 21 % or less in all other parts of the growing and ripe plants. 相似文献
996.
Isospora suis is unequivocally a primary pathogen of swine. Inoculation of I suis in conventionalised and germ-free piglets caused a biphasic disease course with marked diarrhoea, villous atrophy and necrosis of the intestinal epithelium at four to six and eight to 10 days after inoculation. The presence of a normal bacterial flora markedly (P less than 0.05) influenced the survival rate of piglets but did not appear to affect the histopathological changes observed. Mild limited focal necrosis and bile stasis were present in the liver at eight to 10 days after inoculation. In this period there was also ectasia of lymph vessels in the intestinal lymph nodes. 相似文献
997.
Leroy G. Biehl Manford E. Mansfield Arnold R. Smith George T. Woods Richard C. Meyer 《Preventive veterinary medicine》1985,3(5):489-497
Purchased feeder pigs from 12 farms were commingled and divided into three treatment groups of carbadox, lincomycin and controls. Health and performance evaluations included serology, bacterial isolations, fecal examinations and post-mortem examinations at slaughter, weight gain, and feed efficiency.Serological tests for influenza, Aujeszky's disease and Mycoplasma hyopneumoniae were negative throughout the study. Bordetella bronchiseptica was isolated from 14% of the pigs on arrival and from 42% of the pigs 30 days after commingling. No Salmonella spp. were isolated from fecal swabs on arrival; Salmonella typhimurium was isolated from 2.5% of the pigs on Day 30, but no Salmonella was isolated on Day 90. Fecal examination on arrival revealed that 12.5% were infected with gastrointestinal parasites (5.0% Trichuris suis, 5.0% Ascaris suum and 2.5% Strongyloides ransomi).During the 30-day treatment period immediately following purchase and commingling, carbadox and lincomycin improved growth rate by 7.6% and 10.2%, respectively. The treatments also improved feed efficiency, by 9.9% and 5.7%, respectively, and uniformity of growth. Growth rate and feed efficiency were not affected by treatment from Days 30 to 90 following removal of the feed additives from the diet.Growth rate varied greatly, depending on the farm of origin. Although the reasons for the differences in performance were not well established, results suggested that transmission of B. bronchiseptica between pigs resulted in decreased growth rate following infection. Carbadox was significantly more effective than lincomycin in preventing transmission of B. bronchiseptica between commingled pigs.Post-mortem examination at slaughter revealed turbinate atrophy in 5.8% of the noses and pneumonia in 18% of the lungs. One liver exhibited evidence of ascarid larval migration. Treatments produced no significant effect (P>0.05) on post-mortem examination results. 相似文献
998.
999.
1000.