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1.
Sera from 74,502 cattle from 3087 farms in England and Wales were tested for the presence of antibodies against Hypoderma bovis in the spring of 1988. Twenty-nine positive sera were identified on 18 premises and these animals were treated; an examination of 6030 sera taken from 108 neighbouring herds identified another 17 seropositive animals on 10 farms in Devon, Cornwall, Lancashire, Shropshire and Powys, indicating that these counties still harbour populations of warble fly. 相似文献
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Hewitt SA Brisson BA Sinclair MD Sears WC 《American journal of veterinary research》2007,68(4):358-369
OBJECTIVE: To evaluate the use of laparoscopic-assisted jejunostomy feeding tube (J-tube) placement in healthy dogs under sedation with epidural and local anesthesia and compare cardiopulmonary responses during this epidural anesthetic protocol with cardiopulmonary responses during general anesthesia for laparoscopic-assisted or open surgical J-tube placement. ANIMALS: 15 healthy mixed-breed dogs. PROCEDURES: Dogs were randomly assigned to receive open surgical J-tube placement under general anesthesia (n = 5 dogs; group 1), laparoscopic-assisted J-tube placement under general anesthesia (5; group 2), or laparoscopic-assisted J-tube placement under sedation with epidural and local anesthesia (5; group 3). Cardiopulmonary responses were measured at baseline (time 0), every 5 minutes during the procedure (times 5 to 30 minutes), and after the procedure (after desufflation [groups 2 and 3] or at the start of abdominal closure [group 1]). Stroke volume, cardiac index, and O(2) delivery were calculated. RESULTS: All group 3 dogs tolerated laparoscopic-assisted J-tube placement under sedation with epidural and local anesthesia. Comparison of cardiovascular parameters revealed a significantly higher cardiac index, mean arterial pressure, and O(2) delivery in group 3 dogs, compared with group 1 and 2 dogs. Minimal differences in hemodynamic parameters were found between groups undergoing laparoscopic-assisted and open surgical J-tube placement under general anesthesia (ie, groups 1 and 2); these differences were not considered to be clinically important in healthy research dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Sedation with epidural and local anesthesia provided satisfactory conditions for laparoscopic-assisted J-tube placement in healthy dogs; this anesthetic protocol caused less cardiopulmonary depression than general anesthesia and may represent a better choice for J-tube placement in critically ill patients. 相似文献
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M. Gholipoor T. R. Sinclair M. A. S. Raza C. Löffler M. Cooper C. D. Messina 《Journal of Agronomy and Crop Science》2013,199(1):23-29
Drought is ubiquitous in rainfed cropping systems and often limits maize yields. The sensitivity of transpiration response early in progressive soil drying is a trait with potential to improve crop drought resistance. Simulation studies demonstrated that increased sensitivity to drying soil leading to restricted transpiration rates results in conservation of soil water during vegetative stages for possible use during grain filling. In contrast to other crops, there have been no studies characterizing genotypic variability for this trait in maize. Experiments in controlled environments were conducted to characterize the fraction of transpirable soil water (FTSW) threshold on drying soil for 36 hybrids selected for variation in the field for drought resistance, regions of adaptation and stay green. While FTSW thresholds varied among hybrids from 0.60 to 0.33, these thresholds were not uniformly associated with level of drought resistance in the field. Nevertheless, this study demonstrated a high FTSW threshold corresponded with drought resistance observed in some modern maize germplasm (hybrids #7, 17, 24, 27 and 32). This knowledge can enable breeding work seeking to exploit this adaptive trait to improved drought tolerance in low threshold FTSW germplasm. 相似文献
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Ponnampalam EN Sinclair AJ Egan AR Blakeley SJ Li D Leury BJ 《Journal of animal science》2001,79(4):895-903
In a previous study we showed that feeding fish meal significantly increased muscle long chain n-3 fatty acids (FA) and hot carcass weight. In this study we compared the effect of fish meal and fish oil on increasing muscle long-chain FA. We also investigated whether the increase in carcass weight was due to the effect of dietary enrichment of muscle long-chain n-3 FA on muscle membrane phospholipids and(or) to rumen by-pass protein provided by fish meal. Forty crossbred ([Merino x Border Leicester] x Poll Dorset) wether lambs between 26 and 33 kg BW were randomly assigned to one of five treatments: 1) basal diet of oaten:lucerne chaff (Basal); 2) Basal + fish meal (9% DM) = FM; 3) Basal + fish oil (1.5% DM) with protected sunflower meal (9% DM ) = FOSMP; 4) Basal + fish oil (1.5% DM) = FO; or 5) Basal + protected sunflower meal (10.5% DM) = SMP. Daily intake of ME (9.60 - 10.5 MJ ME/d) and CP (150 to 168 g/d) in all treatments was kept similar by varying the ratio of oaten:lucerne chaff and by feeding the animals at 90% ad libitum intake. Blood samples were collected at the start of the experiment and on the day (d 42) prior to slaughter. Lambs were then slaughtered at a commercial abattoir. At 24 h postmortem carcass traits were measured and longissimus thoracis muscle taken for analysis of FA of phospholipid and triglyceride fractions. Lambs fed FO and FOSMP showed a marked increase in muscle longchain n-3 FA (P < 0.001) and a reduction in magnitude of the rise in insulin concentration (P < 0.001) after feeding compared with lambs fed Basal and SMP diets. Lambs in FM had a moderate increase (P < 0.001) in muscle long-chain n-3 FA content. Compared with Basal diet, both plasma total cholesterol (P < 0.02) and high-density lipoprotein cholesterol (P < 0.001) levels were greater in SMP and less in FO and FOSMP treatments. The i.m. fat content was reduced (P < 0.05) in FM and FO treatments, but carcass weight was increased only with fish meal (P < 0.03). Adding SMP to FO produced muscle with an intermediate level of i.m. fat, whereas muscle long-chain n-3 FA, i.m. fat, and insulin concentration were unchanged with SMP treatment. These results indicate that an increase in carcass weight in FM may be due to the supply of ruminally undegraded protein. They also suggest that fish oil along with fish meal can increase long-chain n-3 FA content in phospholipid of muscle membrane. This may be associated with reduced i.m. fat content and altered insulin action and lipoprotein metabolism. 相似文献
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Enzyme-linked immunosorbent assay for the detection of antibodies to the sheep scab mite Psoroptes ovis 总被引:1,自引:0,他引:1
An enzyme-linked immunosorbent assay has been shown to detect antibodies in the circulation of sheep infected with Psoroptes ovis. Strong positive reactions were obtained from 19 sheep with four-month-old infections. No cross reaction was observed with sera obtained from sheep infected with either Fasciola hepatica, Nematodirus battus, Ostertagia circumcincta or Damalinia ovis. 相似文献
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The ruminal degradability, intake, and metabolism of diets differing in their relative rate of energy and nitrogen release in the rumen were characterized prior to their use in a study of the effects of high peripheral levels of ammonia on reproductive function in cattle. In a 2 x 2 factorial experiment, replicated four times, 16 heifers were offered isocaloric and isonitrogenous diets containing two sources of fermentable carbohydrate, fiber (slow energy release, SE) or starch (fast energy release, FE), and two rates of nitrogen release, which were either synchronous (S) or asynchronous (A) to that of energy release. Throughout the experiment, the amount of feed offered was held constant, at a level equivalent to 1.5 x maintenance. Four ruminally fistulated sheep were used to determine the in situ degradability of these diets. The 16 heifers were bled before feeding at 0800 and at 0900, 1000, 1100, 1200, 1400, and 1600 on d 0 (introduction to dietary treatments) and on d 4, 7, 11, 14, 21, and 28. Diet refusals were recorded at hourly intervals after feeding. The rapidly degradable nitrogen fraction of the SE:A and FE:A diets was greater than that of the SE:S and FE:S diets. Postprandial jugular plasma ammonia levels rose to a peak of around 300 micromol/L in heifers offered the SE:A and FE:A diets but did not rise in heifers offered the SE:S and FE:S diets. All feed offered was consumed within 1 h on diets SE:S and FE:S throughout the experiment. The proportion of feed consumed within 1 h of feeding declined from 100% on d 0 to around 70 and 56% by d 21 for heifers given the SE:A and FE:A diets, respectively. Peak postprandial plasma ammonia levels were accordingly lower, at around 160 micromol/L. Plasma urea levels averaged 7 mmol/L and were unaffected by dietary treatment. High plasma ammonia levels were associated with a suppression in the normal postprandial rise in insulin. There was no significant metabolic adaptation to high-ammonia-generating diets, and heifers given these diets modified their pattern of intake in an apparent attempt to avoid excessively high levels of plasma ammonia. 相似文献