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51.
Bacillary rickettsia-like organisms (BRLO) were found in the tick Dermacentor marginatus. They are gram-negative and differ from common bacteria and reckettsiae both in the cultivation conditions and morphology. BRLO are non-pathogenic for ticks and guinea pigs. In our studies they were isolated on half-engorged females of D. marginatus, on which they are still maintained. 相似文献
52.
J Marcaník J Kocisová K Bod'a T Pauer M Belák R Skarda 《Archives of Animal Nutrition》1976,26(11):757-763
Histological and histochemical studies were carried out on the gastro-intestinal mucosa of three experimental cows (roughages/maize silage) and three control animals. The animals were slaughtered on termination of the long-term trial. Mucosa samples were taken, for further study, from the rumen, the duodenum, the jejunum, the large intestine and the appendix. Histochemical analysis did not reveal any essential differences in the activities of non-specific esterase, alkaline and acid phosphatase and lactic acid dehydrogenase in the mucosa of the rumen, the large and the small intestine and the appendix of both the experimental animals and the controls. The experimental animals were found to exhibit a higher rate of glutamate-dehydrogenase activity in the ruminal mucosa and in the mucosa of the large and small intestine. A higher succinate dehydrogenase activity was observed in the ruminal mucosa of the experimental animals, relative to that of the controls, while the activity in the intestinal mucosa was decreased. Only slight changes were noted in the activity of the enzymatic systems tested. Electron microscopic studies did not reveal any differences in the ultrastructure of the epithelial cells of the ruminal mucosa in both the experimental animal and the controls. 相似文献
53.
54.
The protective effect of a lyophilized vaccine against Marek's disease ("Keramvac"--Pfizer), prepared from a cell-free turkey's herpesvirus (strain FC 126), was compared in field trials with losses in the group of non-vaccinated chickens. Under the indicated conditions, the vaccine had only a 50.86% effectiveness. The possible causes of the reduced vaccination effect are discussed with regard to the pathomorphological and virological findings suggesting, among others, an increased incidence of the symptoms of the classical form of Marek's disease in the population investigated. 相似文献
55.
56.
Attack of tea plant (Camellia sinensis (L.) O. Kuntze) leaves by the tea mosquito bugHelopeltis theivora (Hemiptera: Miridae) was positively correlated to temperature and rainfall, and partially to humidity, as determined in 12
varieties during the period 2000–2002. The insect attack was severe during the months of May–September, which had high temperature
and rainfall, and led to severe loss of biomass due to curling and drying up of the leaves. The biochemical response of these
12 varieties of tea to attack by the insect was determined with special reference to oxidative enzymes and flavonoid flavor
components. Insect attack led to an increase in the activities of the oxidative enzymes peroxidase, ascorbate peroxidase and
polyphenol oxidase. Activities of phenyl alanine ammonia lyase generally decreased as a result of insect attack, which was
significant in the United Planters Association of South India (UPASI) varieties. A significant decrease in polyphenols was
also obtained in UPASI varieties. HPLC analysis of catechins revealed a decrease in some of the catechins in the infected
leaves. Analysis of theaflavins from infusion of healthy andHelopeltis-infested tea leaves revealed no changes.
http://www.phytoparasitica.org posting Dec. 19, 2004. 相似文献
57.
The effect of true milk use in the diet of Spanish Brown Swiss male calves on animal performance, carcass and meat quality, and fatty acids composition was studied. In experiment 1, the effect of milk intake [ad libitum continuous (ADLIB) feed vs. restricted 0.7 during 75 days followed by ad libitum feed (RESTR)] and slaughter endpoint (225 kg vs. 5 month) were studied. In experiment 2, ad libitum concentrate feeding [grain-fed (GF)] was compared with milk supplementation until slaughter [milk-fed (MF)] in calves slaughtered at 345 kg. As regards to milk intake, carcass weight and degree of fatness were higher in the ADLIB group (P<0.05). The RESTR group revealed a higher percentage of saturated fatty acids (P<0.05). In experiment 2, the MF group exhibited a higher fat percentage (P<0.05), lower press and cooking losses (P<0.05), and higher scores for tenderness and juiciness (P<0.05) than the GF group. The percentage of saturated fatty acids was higher in the MF group (P<0.05). The results suggest that true milk use in veal production could be an advantageous alternative in terms on production costs, animal performance, and carcass and meat quality. 相似文献
58.
Bhupender Singh Fernando Saravia Renée B?ge Heriberto Rodríguez-Martínez 《Acta veterinaria Scandinavica》2005,46(1):1-12
Hormonal asynchronies during oestrus, related to the presence of suprabasal plasma-progesterone (P4) concentrations and a delayed ovulation, interfere with the fertility of repeat-breeder heifers (RBH). Since tubal dysfunction can occur in connection with hormonal asynchronies and constrained availability of fertile spermatozoa at the time of ovulation, the present study tested the hypothesis that frequent sperm deposition from onset of oestrus to ovulation may improve pregnancy rates in RBH. Five RBH and five virgin heifers (VH; controls) were repeatedly artificially inseminated (AI) at 6 h intervals from onset of oestrus to spontaneous ovulation. Hormone analyses revealed suprabasal P4 concentrations and a delay in the occurrence of the luteinising hormone (LH) surge, but a normal cortisol profile in RBH. Compared with controls, RBH presented longer interval from onset of oestrus to ovulation, and therefore, received more AIs. Pregnancy rates in RBH reached control levels (60%; NS), indicating that the hypothesis might be correct. Pregnancy rates in VH were below the expected range, presumably attributed to a deleterious influence of the frequent handling. The study suggests that pregnancy rates can be improved in RBH by frequent AI in relation to spontaneous ovulation. However, this practice of repeated manipulations, while seeming not to show adverse effects, lacks practicality for routine use. 相似文献
59.
V. Bontempo 《Veterinary research communications》2005,29(2):45-50
Maintaining the health of dogs and cats by feeding wholesome nutritional diets is becoming an important component of responsible pet ownership. Pet owners now seek a long and healthy life for their pet and look to nutrition, as well as to veterinary medicine, to provide such support. Quality of life, measured in terms of reduced incidence of diseases and the ability to maintain an active life, would appear to be able to be enhanced by appropriate nutrition and nutraceutical supplementation. As a consequence numerous improvements in companion animal nutrition have resulted in development of a wide array of foods that provide complete and balanced nutrition. As a result emphasis also has to be placed on product safety and quality parameters, in connection with traceability. The origin of products, including product characteristics and properties, processing conditions and further handling throughout the period chain, is becoming ever increasingly an issue for collective chain management. 相似文献
60.