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71.
Eman A Elwakeel Evan C Titgemeyer Zongjia J Cheng Abdelaziz M Nour Mohamed EA Nasser 《畜牧与生物技术杂志(英文版)》2012,3(2):93-99
Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent- extracted soybean meal (n = 5) were obtained from People’s Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets. 相似文献
72.
73.
Summary Microtubers of potato cultivar Kennebec were stored for two months at 2 or 8°C and sampled at selected intervals for the determination
of glucose, fructose, sucrose and sprout weight. The aim of this experiment was to determine whether these microtubers show
the same response to storage temperature with respect to sweetening as field grown tubers. During storage at 2 °C, reducing
sugars and sucrose increased rapidly to a concentration of over 1.0 and 0.7 g/100 g fresh weight, respectively. In contrast,
in tubers kept at 8°C, only a relatively slight increase in reducing sugar concentration to 0.3 g/100 g fresh weight was observed
and sucrose concentration remained virtually the same. 相似文献
74.
Root production and root mortality of winter wheat grown on sandy and loamy soils in different farming systems 总被引:6,自引:0,他引:6
Bernd Steingrobe Harald Schmid Reinhold Gutser Norbert Claassen 《Biology and Fertility of Soils》2001,33(4):331-339
Winter wheat was grown over 2 years (1995, 1996) in an organic and integrated cropping system on sandy and loamy soils. Root growth was measured on five to six occasions each year with an auger sampling procedure and the ingrowth core method. The first resulted in an estimate of net root development, while the latter revealed gross root growth (GG) or root production. Total root production was about 80-150 km m-2 (0- to 30-cm soil layer) between April and July and exceeded the net size of the root system at harvest by a factor of between 2 and 4. The C input into the soil could be estimated as 1.4-2.6 t ha-1 by this root production. The cropping systems had nearly no influence on root production. The largest differences occurred between the years. The net root length tended to be lower on sandy soils compared to the loam, but total root production was higher. Root mortality, which is the difference between GG and net root growth, was also higher on sandy soils. The turnover index, which is the mean of the relative root production rates and relative root mortality rates, was positively related to the soil sand content in both years. 相似文献
75.
Phosphate Diffusion Coefficients in Soil as Affected by Bulk Density and Water Content 总被引:1,自引:0,他引:1
Phosphate diffusion coefficients (De) were determined by the quantity of P that diffused from a soil block with P addition into a soil block without P addition. To compare the results with theoretical concepts and to quantify the influencing factors, De was also calculated using the equation of Nye (1968). This equation takes into account the P diffusion coefficient in water, D1, the volumetric water content, θ, the impedance factor, f, and the buffer power, b, of the soil. The results show that De strongly depends on volumetric water content whereas the effect of bulk density on De values was relatively small. If the weighted average buffer power was used, calculated De values were in good agreement with measured values at higher soil moisture contents. At θ < 0.22 g cm?3 the measured values for De were smaller than the calculated. This effect is attributed to incomplete contact between the two soil blocks. The only small influence of bulk density on De is caused by the fact that bulk density affects both θ and b in a way which compensates each other. 相似文献
76.
77.
Motility Characteristics and Fertilizing Capacity of Boar Spermatozoa Stained with Hoechst 33342 总被引:1,自引:0,他引:1
JM Vazquez EA Martinez I Parrilla MA Gil X Lucas J Roca 《Reproduction in domestic animals》2002,37(6):369-374
Flow cytometry sorting of spermatozoa using fluorescence dye Hoechst 33342 is the only effective sex selection methodology validated in numerous laboratories. This study was carried out to determine the effect of Hoechst 33342 on the motility and fertility of stained boar spermatozoa. Experiment 1 evaluated motility parameters (percentage of motile spermatozoa, velocity, angularity and oscillation) of boar spermatozoa stained with Hoechst 33342 by a computer‐aided sperm analysis (CASA) instrument. Spermatozoa (30 million/ml) were divided into five treatment groups and stained during 1 h at 35°C with 9, 18, 27, 60 and 90 μM of H33342. There were no differences in sperm motility patterns nor percentages of motile spermatozoa incubated in the presence of 9, 18 or 27 μM. Percentage of motile spermatozoa and motility parameters decreased significantly (p < 0.05) at 60 μM of Hoechst 33342. Spermatozoa were immotile at concentration of 90 μM. In experiment 2, pregnancy rates, farrowing rates and litter size from sows (n = 275) artificially inseminated (AI) with either Hoechst 33342 stained (27 μM) or unstained (control) spermatozoa were determined. Sows inseminated with stained spermatozoa had no significant lower pregnancy rate (88.33%) as compared with controls (90.32%). Staining neither affected farrowing rates (85.0 vs 87.7%) nor total number of piglets born (10.56 ± 0.32 vs 10.47 ± 0.24, stained and controls, respectively). No phenotypical abnormalities were registered among the newborn piglets. The data suggest that incubating spermatozoa with Hoechst 33342 at levels required for X‐ and Y‐bearing chromosome sperm sorting, does not impair sperm viability or their fertility after AI. 相似文献
78.
Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur. 相似文献
79.
Summary Uptake efficiency (in terms of shoot K content) of potato decreased with time compared to that of wheat at a deficient K level
of 1.5 μM. This resulted from the decrease in root-shoot ratio with time for potato only. Both shoot and root growth rates
of potato depended on solution K levels in the initial stages and were greater at higher K levels. At optimum K, uptake efficiency
of potato increased with time and this was due to the increased K-influx with time. The K concentration of 4–5% in the potato
shoot was sufficient to achieve 90% of maximum shoot growth rate. Plants grown at optimum K concentration attained shoot K
content of 4–5% rapidly and achieved maximum shoot growth rate faster than those grown at low K concentration. 相似文献
80.
S Herr L M Ribeiro E Claassen J G Myburgh 《The Onderstepoort journal of veterinary research》1991,58(1):41-45
Seven batches of 25% water-phase, oil-in-water vaccine were prepared from whole cultures of Tritrichomonas foetus. Two inoculations were given, spaced 6 weeks apart, to virgin heifers and infected bulls. A significant reduction (P less than 0.01) in the duration of infection in vaccinated heifers was seen when they were challenged by being bred to a bull infected with the same isolate as that contained in the vaccine. Only 1/12 vaccinated heifers were pregnant 4.5 months after the end of the breeding season compared to 2/12 in the control group. The vaccine, therefore, has no practical advantage. Vaccine was supplied to 2,724 bulls on properties where the infection was present. From these bulls, 110 reliable results were obtained, where bulls had been infected, been inoculated and tested 1 month later. No curative effect was demonstrable with 69/110 (62.7%) bulls, remaining infected after the course of inoculations. There was also no difference between vaccine batches or between bulls of different ages. Further work on improving the vaccine is indicated. Three media suitable for the culture of T. foetus are described in detail. 相似文献