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901.
Insecticides which were environmentally friendly and the least toxic, were screened against a laboratory strain ofBracon hebetor (Say) (Hymenoptera: Braconidae) for their suitability for release in IPM of cotton. Concentrations ranging from 1 to 1000
ppm of the formulated insecticides in acetone were applied in glass vials and also by a leaf method, whereby cotton leaves
were dipped in aqueous solutions of the same concentrations of insecticides. Adult parasitoids were exposed in both methods.
According to the LC50 at 24 h exposure, Λ-cyhalothrin and spinosad were the most (7 and 5 ppm) and least (263 and 225 ppm) toxic in the vial and
the leaf method, respectively, toB. hebetor. The possible use of the parasitoid for IPM of cotton is discussed.
http://www.phytoparasitica.org posting July 20, 2006. 相似文献
902.
Skinner GR Ahmad A Davies JA 《Comparative immunology, microbiology and infectious diseases》2001,24(4):255-269
The infrequency of natural transmission of herpesviruses between humans and animals is surprising as there is extensive contact between humans and non-human species with unequivocal evidence that host cells from non-susceptible species will support replication of herpesviruses which do not seem to naturally infect that species. This review examines natural cross-infections between human and other species and suggests that, firstly, it is possible that humans and animals do become asymptomatically or symptomatically cross-infected from other species, but the infection is not diagnosed or not diagnosable by conventional methods; secondly, an as yet unidentified novel mechanism(s) may operate to prevent infection using chemical, electrical or as yet unidentified pathways and may even be ‘switched on’ by exposure to the virus. 相似文献
903.
Efficacy of macrocyclic lactones for the control of larvae of the Old World screw-worm fly (Chrysomya bezziana) 总被引:1,自引:0,他引:1
OBJECTIVE: To assess the efficacy of four macrocyclic lactones for the control of larvae of the Old World Screw-worm Fly (OWS), Chrysomya bezziana, and to examine the effects of excreted residues on the dung fauna. ANIMALS: 100 heifers were divided into five groups of 20 animals. One group remained untreated, whereas the other groups were treated respectively with pour-on formulations of moxidectin, eprinomectin or doramectin, or a sustained-release bolus of ivermectin. PROCEDURES: At intervals of 1 to 15 weeks after treatment, five cattle from each group were challenged with newly-laid eggs of OWS. The efficacy of each treatment was determined 48 h later by comparing the number of myiases in the treated and untreated groups. Abundance of fly larvae in naturally-voided dung pads and the survival of a species of dung beetle, Onthophagus sagittarius, were used to assess the effects of drug residues on the dung fauna. RESULTS AND CONCLUSIONS: Moxidectin showed no activity against larvae of OWS during the first 14 days after treatment. Eprinomectin provided protection for 3 days after dosing, but failed at days 7 and 14, whereas doramectin was effective at day 7, but not at days 14 or 21. In contrast, no myiases were established on bolus-treated cattle from 14 to 102 days after treatment. Faecal residues of moxidectin had no effect on the survival of larvae of dung-feeding flies, whereas those of eprinomectin and doramectin reduced survival for 1 to 2 weeks. Dung voided by bolus-treated cattle inhibited fly breeding and had adverse effects on the development and survival of O sagittarius for up to 15 weeks after treatment. 相似文献
904.
SA Bukhari N Ahmad N Akhtar A Ijaz MS Yousaf IU Haq 《Reproduction in domestic animals》2008,43(6):664-671
In the present study, ovarian follicular fluid and serum biochemical, hormonal, electrolytes and amino acids profiles in female dromedary camel (Camelus dromedarius), were investigated. Fluid from small (2–6 mm) and large follicles (7–20 mm) and blood samples were collected from 25 clinically healthy adult female camels. The concentrations of glucose, cholesterol, triglycerides, high‐density lipoproteins, urea, total proteins, albumin, globulin, fibrinogen, alanine aminotransferase, aspartate aminotransferase and tri‐iodothyronine were lower (p ≤ 0.05) in large follicles when compared with the small follicles. However, the concentrations of low‐density lipoproteins, uric acid, creatinine, alkaline phosphatase and acid phosphatase in small and large follicles did not differ. The concentrations of oestradiol 17‐β and progesterone were higher (p ≤ 0.05) in large follicles. The serum concentrations of these hormones were many folds lower (p ≤ 0.05) than those of follicular fluid. Among electrolytes, the concentration of phosphorus was higher (p ≤ 0.05) in the large follicles, while that of potassium and chloride were lower (p ≤ 0.05) in the small follicles. Serum concentrations of sodium, chloride, calcium and phosphorous were higher (p ≤ 0.05), while that of potassium lower (p ≤ 0.05) than corresponding concentrations in the follicular fluid. The concentrations of leucine and arginine were higher (p ≤ 0.05) in follicular fluid when compared with serum concentrations, while the reverse was true for other amino acids. In conclusion, this study is indicative of either low or high concentrations of certain biochemical metabolites, hormones, electrolytes and amino acids in small and large follicles for the individual roles that they play in the growth and development of follicles in the one‐humped she‐camel. 相似文献
905.
Ibrahim RM Goll DE Marchello JA Duff GC Thompson VF Mares SW Ahmad HA 《Journal of animal science》2008,86(6):1426-1433
The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values, and low calpastatin activity, all of which are related to more tender meat. 相似文献
906.
Al-Majali AM Al-Qudah KM Al-Tarazi YH Al-Rawashdeh OF 《Tropical animal health and production》2008,40(3):193-200
During the period between February, 2004 and December, 2006, a cross-sectional study was performed to investigate some epidemiological
aspects related to camel brucellosis in Jordan. Four hundred twelve camel sera from 37 herds were randomly collected and analyzed
using Rose Bengal plate test and complement fixation test. A structured pre-tested questionnaire was administered to collect
information on camel herd health and management. A multivariable logistic regression model was constructed to investigate
risk factors associated with seropositivity to Brucella antigens. Moreover, the incidence of Brucella-specific abortion was investigated in 7 camel herds located in different locations in Southern Jordan. The true prevalence
of Brucella-seropositive in camels was 12.1%. Thirteen (35.1%) herds had at least one positive camel. The seroprevalence of brucellosis
in camels was significantly higher in the southern part of Jordan than that in central or northern Jordan. The multivariable
logistic regression model on both individual and herd levels revealed large herds and contact with small ruminants as risk
factors for Brucella seropositivity. On the other hand, using disinfectants was identified as a protective factor (OR = 0.8; 95% CI: 0.1, 0.9)
only on the camel herd level. The incidence of Brucella-caused abortion was 1.9%. Brucella melitensis biotype 3 was isolated from 4 aborted camel fetuses. 相似文献
907.
Seroprevalence of, and risk factors for, peste des petits ruminants in sheep and goats in Northern Jordan 总被引:1,自引:0,他引:1
Peste des petits ruminants (PPR) is an economically important disease that affect sheep and goat industry in Asia and Africa. In this study, we investigated the seroprevalence, and risk factors, of PPR in sheep and goat flocks from five different governorates (Irbid, Jarash, Ajloun, Mafraq and Zarka) located in Northern Jordan. Serum samples from 929 and 400 sheep and goats, respectively, corresponding to 122 sheep flock and 60 goats flock were collected. Seroprevalence was determined using PPR competitive ELISA. Health status and management information were collected using a semi-structured pre-tested questionnaire. The individual true prevalence of PPR in sheep and goats was 29 and 49%, respectively. The flock level true prevalence of PPR was 60 and 74% in sheep and goats, respectively. In both sheep and goat flocks, large flock size, visiting live animals market and inadequate veterinary services were identified as risk factors for PPR seropositivity. Mixed (sheep and goats) raising was identified as a risk factor for PPR seropositivity in sheep flocks only. 相似文献
908.
909.
Ahmad Yar Ranjha Richard C. Peralta Antonio Maria Requena Howard M. Deer Majid Ehteshami Robert W. Hill Wynn R. Walker 《Irrigation Science》1992,13(1):9-14
Summary Effects of furrow irrigation designs, water management practices (irrigation scheduling, etc.), soil types and pesticide parameters on pesticide leaching were simulated. A hydraulic kinematic-wave irrigation model was used to estimate water infiltration for alternative furrow lengths and inflow rates. A one-dimensional simulation model then simulated the movement of pesticides through soils following furrow irrigation. Potential ground-water contamination by pesticides can be reduced by an integrated use of the best management practices (BMPs) such as careful selection and use of pesticides, efficient furrow irrigation designs and improved water management techniques (irrigation scheduling, etc.). Procedures for designing an appropriate furrow irrigation system for a particular site and pesticide, and selecting pesticides for a particular site, crop and furrow irrigation system are illustrated. These procedures are being used to develop decision support computer models for developing different BMPs for pesticide-agricultural management decisions. 相似文献
910.