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71.
Sudershan Kumar Anil K. Srivastava V. K. Dumka Naresh Kumar Rajinder K. Raina 《Veterinary research communications》2010,34(6):503-510
Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous
administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition
followed three-compartment open model. The values of Vdarea, AUC, t1/2β, ClB, MRT and P/C ratio were 0.50 ± 0.19 L.kg−1, 62.2 ± 23.3 μg.ml−1.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg−1.h−1, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg−1, 37.0 ± 17.1 μg.ml−1.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg−1.h−1, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration.
For MIC90 of 0.5 μg.ml−1 the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg−1 repeated at 6 h intervals for the treatment of endometritis in cows. 相似文献
72.
Sara Frosth Ulrika König Ann-Kristin Nyman Anna Aspán 《Veterinary research communications》2017,41(3):189-193
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples. 相似文献
73.
Circulating oxidative stress status in dromedary camels infested with sarcoptic mange 总被引:2,自引:0,他引:2
Oxidative stress is an imbalance between radical-generating and radical-scavenging activity, resulting in oxidation products
and tissue damage. This study was aimed to evaluate the status of oxidative stress indices in blood of camels naturally infested
with S. scabiei. Forty-seven male camels (Camelus dromedaries) were divided according to the extent of the infested area with Sarcoptes scabiei into four groups, mild (MID, n = 12), moderate (MOD, n = 10), severely infested (SEV, n = 10) and healthy control group (n = 15). Blood was used for determination of red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV), serum nitric
oxide (NO•, a free radical), ascorbate and albumin concentrations, and erythrocytic values of malondialdehyde (MDA, a marker of lipid
peroxidation), protein carbonyls (PC, an indicator of protein oxidation), glutathione (GSH) superoxide dismutase (SOD) and
catalase (CAT). Decreased levels (P < 0.05) of RBC, Hb, PCV, albumin and ascorbate were noticed in MOD and SEV compared to controls with the lowest values (P < 0.05) in SEV except for ascorbate, where MOD did not differ from SEV. Compared to controls, NO• gradually increased (P < 0.05) in MID followed by MOD and SEV, whereas MDA and PC were higher (P < 0.05) in MOD and SEV. PC was higher (P < 0.05) in MOD than SEV. In addition, the antioxidants GSH, SOD and CAT were higher (P < 0.05) in MID and lower (P < 0.05) in MOD and SEV compared to controls. GSH was lower (P < 0.05) in SEV compared to MOD. Besides, Hb was negatively correlated with NO• (r = −0.68, P < 0.001), MDA (r = −0.53, P < 0.001) and PC (r = −0.73, P < 0.001). In conclusion, dromedary sarcoptosis is accompanied by a state of oxidative stress process, which increased by
increasing the area of infestation, and may contribute to the pathogenesis of the disease. 相似文献
74.
Millogo V Norell L Ouédraogo GA Svennersten-Sjaunja K Agenäs S 《Tropical animal health and production》2012,44(5):1017-1025
The aim of the study was to test three different hand-milking techniques (“pull down”, “thumb in”, and “full hand grip”) and
their effects on milk production and teat treatment. This is important since milk production in many tropical areas still
rely on hand-milking. The study was carried out at a peri-urban farm in the Bobo-Dioulasso area in Burkina Faso. Twelve indigenous
Zebu cows in early lactation were used in the study. The sequences of the treatments (hand-milking techniques) and the milkers
were balanced for carry-over effects between successive periods and days, respectively. The sequences were constructed by
using special Latin squares. Yield and composition of saleable milk was not affected by milking technique but there were differences
between the milkers in milk yield. There was also a significant interaction for saleable milk yield between milker and milking
technique. Hemoglobin in milk was measured as an indicator of teat damage. The hemoglobin content was numerically higher in
post-milking strip milk samples than in saleable milk. It was concluded that the amount of milk removed depends mainly on
the milker and how well the milking technique works for the individual milker. No effect of milking technique was observed
on teat treatment. 相似文献
75.
Cryptosporidiosis in buffalo calves (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>): Prevalence and potential risk factors 总被引:1,自引:0,他引:1
The objective of the present study was to describe the prevalence and risk factors associated with cryptosporidiosis in buffalo calves in Middle Egypt. During one year, 458 fecal samples were collected from buffalo calves less than 3 month age in 55 small scale herds and examined for the presence of Cryptosporidium oocysts. Data describing age, gender, season, and herd management practices were gathered to assess potential risk factors. Fecal examination showed that 14.19% of the examined calves were positive for Cryptosporidium spp. Calves at 1-15 days were at the highest risk (P < 0.001), and a significant relationship between season and infection (P < 0.05) was recorded. A significant association between infection and hygiene (P < 0.001), type of floor (P < 0.01) and source of water (P < 0.01) was also recorded. Statistical analysis concerning the clinical signs and fecal characteristics revealed a significant association with fecal consistency (P < 0.001), presence of blood (P < 0.01) and mucous (P < 0.01). Moreover, a significant association was found between infection and the desire for suckling (P < 0.05) and tenesmus (P < 0.05). The results of the present study demonstrated the strong relation between infections by Cryptosporidium spp. and diarrhea in buffalo calves. 相似文献
76.
77.
T. Reg Preston 《Tropical animal health and production》2009,41(7):1071-1080
Responding to the challenges posed by global warming, peak oil and biofuels will require a paradigm shift in the practice
of agriculture and in the role of live stock within the farming system. Farming systems should aim at maximizing plant biomass
production from locally available diversified resources, processing of the biomass on farm to provide food, feed and energy
and recycling of all waste materials. The approach that is the subject of this paper is that the generation of electricity
can be a by-product of food/feed production. The concept is the fractionation of biomass into inedible cell wall material
that can be converted to an inflammable gas by gasification, the gas in turn being the source of fuel for internal combustion
engines driving electrical generators. The cell contents and related structures such as tree leaves are used as human food
or animal feed. As well as providing food and feed the model is highly appropriate for decentralized small scale production
of electricity in rural areas. It also offers opportunities for sequestration of carbon in the form of biochar the solid residue
remaining after gasification of the biomass. 相似文献
78.
Morehead JP Blanchard TL Thompson JA Brinsko SP 《Journal of the American Veterinary Medical Association》2002,220(12):1828-1830
OBJECTIVE: To determine features of an early fetal loss (EFL) syndrome and evaluate potential risk factors for EFL in Thoroughbred broodmares on 4 farms in central Kentucky. DESIGN: Retrospective study. ANIMALS: 288 pregnant broodmares. PROCEDURE: Year-2001 breeding records for 288 Thoroughbred broodmares were examined. Early fetal loss was defined as loss of a fetus that was viable at > or = 40 days of gestation but was subsequently lost by 5 months of gestation. RESULTS: Overall 2001 EFL rate was 25% (73/288), median gestational age at time of fetal loss was 77 days, and median date of loss was May 7. Mares on 1 farm had significantly fewer fetal losses (5%) than mares on the other 3 farms (26 to 35%). Fetal losses were higher for maiden (42%) and barren (42%) mares than for foaling mares (18%). Fetal losses were greater in young than in older mares. Effects of broodmare farm, mare age, and reproductive status were all significant. Fetal losses were not associated with sire used for mating or stud farm. CONCLUSIONS AND CLINICAL RELEVANCE: Greatest risk for EFL occurred during the period from late April to May (ie, in mares bred during February through March). Higher incidence of EFL in maiden and barren mares and lower incidence of EFL on 1 farm suggest management or environmental influences may have affected outcome. Risk factors that should be investigated include environmental differences among farms and differences in management procedures used for lactating versus nonlactating mares. 相似文献
79.
Anthea L. Katelaris Keira Glasgow Kerryn Lawrence Paul Corben Anthony Zheng Suhasini Sumithra John Turahui Janet Terry Debra van den Berg Daneeta Hennessy Stacey Kane Scott B. Craig Ellena Heading Mary‐Anne Burns Hanisah L. Corner Vicky Sheppeard Jeremy McAnulty 《Zoonoses and public health》2020,67(1):35-43
80.