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981.
In general, there is a lack of scientific documentation of nutritional value of marine by‐products. The bone fraction from fish has been regarded as waste. Due to the high mineral content of fish bones, this material can be well suitable as a natural calcium source. In the present study, apparent calcium absorption of different fish bone sources was tested using growing pigs. The experimental diets consisted of boiled salmon frames, or salmon, saithe or cod bones treated with enzymes. Calcium carbonate (CaCO3) was used as control. The experimental diets were formulated to contain 0.7% total calcium of which the added calcium source to be tested contributed about 71% (study 1) and 86% (study 2). Except for the calcium and phosphorus sources, the animals received similar basal diets. Apparent calcium digestibility coefficient was calculated using yttrium as indicator (both studies) and was based on complete collection of faeces and urine (study 2). The experimental design was parallel and cross‐over in study 1 and study 2, respectively. In study 1, piglets getting salmon bone treated with enzymes had significantly higher calcium absorption than piglets getting boiled fish bone or calcium carbonate. Therefore, in the second study only enzymatically treated fish bones were included. The higher calcium absorption from enzymatically treated salmon bone was also found in study 2, but this time not significant. Calcium from boiled salmon bones in study I, and from enzymatically treated saithe and cod bones in study II were absorbed as well as the calcium carbonate control. The results indicate that fish bones may be a useful and well absorbed calcium source. Due to the high mineral content of the bone fraction, salmon bones can be well suitable as a natural calcium and phosphorus source in, for example, food, feed or as supplement.  相似文献   
982.
Background: Real‐time 3‐dimensional echocardiography (RT3D) is a recent technique based on volumetric scanning, eliminating the need for geometric modeling of the cardiac chambers and minimizing the errors caused by foreshortened views. Hypothesis: Estimations of left ventricular (LV) end‐diastolic (EDV) and end‐systolic volume (ESV), and left atrial (LA) size, differ depending on the echocardiographic technique of estimation. Animals: Fifty‐one dogs with acquired heart disease and 34 healthy control dogs. Methods: Prospective observational study by M‐mode (Teichholz method), Simpson's modified 2‐dimensional (2D) method, and RT3D methods for estimation of LV volumes. LA size was evaluated by 2D and RT3D methods. Results: RT3D showed good agreement with 2D for EDV and ESV, whereas Teichholz method overestimated LV volumes in comparison with the other 2 methods by approximately a factor 2. There were no statistically significant differences among the 3 methods in estimating ejection fraction. Comparison between RT3D assessment of LA end‐systolic volume per kilogram (LAs/kg) and LA to aortic ratio (LA/Ao) measured by 2D relative to each other showed that the RT3D method underestimated LAs/kg at lower values, and overestimated it at higher values. The difference between methods increased with increasing LA size. Conclusions and Clinical Importance: There was good agreement between RT3D and 2D methods of estimating EDV and ESV, whereas the Teichholz method overestimated LV volumes by approximately a factor 2. In comparison with RT3D, LA/Ao underestimated LA size, especially when LA was enlarged.  相似文献   
983.
The influence of different copper and zinc contents in rations on blood serum concentrations was tested in a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute for Animal Health (FLI). A total of 60 German Holstein breed cows (38 first lactating and 22 second lactating cows) were tested. All animals received a diet based on maize‐ and grass silage ad libitum. The animals were divided into two groups with 30 cows each. Group A received concentrates supplemented with copper and zinc as recommended, whereas Group B was offered a concentrate with roughly double the amount of copper and zinc. Blood samples were taken several times during the lactation. The concentrations of copper and zinc in the serum were measured and correlations between trace element intake and their serum concentrations were calculated. The mean dry matter intake was significantly higher for cows in the second lactation (19.1 kg/day) than for cows in the first lactation (16.4 kg/day), whereas the DM‐intake was constant in the different feeding groups (17.3 and 17.4 kg/day). The correlation between feed intake in the first and the second lactation was r = 0.76. The copper concentration in the serum was not influenced by the different feedings (11.9 and 12.5 μmol/l), but high variations were found between the cows. The influence of the lactation number was not significant (12.1 and 12.4 μmol/l). In contrast to copper, the zinc concentration in the serum was significantly higher for Group B (14.0 μmol/l) than for Group A (12.2 μmol/l), respectively, for second lactating cows (13.8 μmol/l) in relation to 12.7 μmol/l for first lactating cows. The individual variation was also high as for copper. Neither the correlation between copper intake and copper serum concentration nor the correlation between zinc intake and zinc serum concentration was significant.  相似文献   
984.
Effect of humic acid (HA) and fulvic acid (FA) on production parameters, immune response and thyroid function of rats were investigated in two experiments. First experiment: control or 0.1%, 0.2%, 0.4%, 0.8% HA- or FA-supplemented diets. Second experiment: control and 0.4% HA- or FA-supplemented diets. The feeding period lasted 26 days in both trials. No significant changes were observed in production parameters. Ovalbumine antibody titre of rats on HA- or FA-supplemented diets showed dose-dependent (at 0.4% supplementation) and significant (p < 0.05) increase (350 and 418% respectively) over the control (100%). Dose-related increase of plasma TSH (r = 0.99), and decrease of the T(4)/T(3) ratio (r = -0.97) was observed in FA-supplemented rats. Second experiment: both FA and HA stimulated the immune response by the 14th day (mean values: control: 685.79; FA: 1131.37; HA: 1055.6099) and 26th day (control: 544.31; FA: 1969.83; HA: 1600.00). No significant differences were noted with lymphocyte stimulation test. Diameter of the 'B'-dependent lymphoid tissues in the ileum and spleen were significantly (p < 0.05) larger in both the FA- and HA-treated animals. Humic acid and FA supplementation resulted in strong humoral immune stimulation. Our data also indicate that FA content is responsible for the mild hypothyroid effect of humic substances.  相似文献   
985.
The aim of this study was to research the population structure and genetic diversity of the Nova Scotia Duck Tolling Retriever (NS) and the Lancashire Heeler (LH) dog breeds. Data consisted of nearly all the worldwide registration history for both breeds, including 28 668 NS and 4 782 LH individuals. A reference population, including the females born between 1999 and 2008, was defined for genetic analyses for each breed. Average depth of the pedigrees known for the reference population dogs was 12.9 complete generation equivalents in the NS and 6.0 in the LH. Only a small fraction of the born dogs were used later for breeding. Effective number of founders was 9.8 in the NS and 15.2 in the LH. More than 50% of the genetic diversity in the reference population was explained by two ancestors in the NS and five in the LH. Average inbreeding coefficients in the reference populations were 0.26 in the NS and 0.10 in the LH. Average kinships were 0.26 and 0.08 and realised effective population sizes 18 and 28, respectively. Failure to use available genetic resources for sustainable breeding has resulted in depletion of genetic variation in both breeds. To increase genetic variation, a larger proportion of the dogs should be used in reproduction and the contributions of reproducing animals should be equalized. In the LH, it is necessary to use the unregistered farm dogs in breeding. In the NS, crosses with another breed are needed.  相似文献   
986.
On the course of a helminthological survey of the dogs of Baranya County, Hungary Angiostrongylus vasorum infection was detected in two asymptomatic dogs. Identification of the parasite was based on morphology of the first-stage larvae (L1) isolated from droppings, and successful experimental infection with first stage larvae to laboratory reared Discus rotundatus and Lissachatina fulica snails, in order to exclude species of the family Filaroididae that have similar larvae to A. vasorum. While angiostrongylosis is widespread among foxes, this is the first report of A. vasorum infection in housedog in Hungary. In gardens, where infected dogs were being kept 91 specimens of 6 species of limacid and arionid slugs were collected of which 5 specimens of Arion lusitanicus were found to carry larvae of A. vasorum. Dogs usually do not ingest such large slugs willingly. Frogs are known to act as paratenic hosts in the life cycle of A. vasorum. Since one of the infected dogs harboured also infection with the intestinal trematode Alaria alata, of which frogs certainly play the role of the second intermediate host, therefore it is assumed that in this case the dog became infected with A. vasorum by eating frogs.  相似文献   
987.
988.
989.
ObjectiveTo compare racemic ketamine and S-ketamine as induction agents prior to isoflurane anaesthesia.Study designProspective, blinded, randomized experimental study.AnimalsThirty-one healthy adult goats weighing 39-86 kg.MethodsGoats were premedicated with xylazine (0.1 mg kg?1) intravenously (IV) given over 5 minutes. Each goat was assigned randomly to one of two treatments for IV anaesthetic induction: group RK (15 goats) racemic ketamine (3 mg kg?1) and group SK (16 goats) S-ketamine (1.5 mg kg?1). Time from end-injection to recumbency was measured and quality of anaesthetic induction and condition for endotracheal intubation were scored. Anaesthesia was maintained with isoflurane in oxygen for 90 minutes. Heart rate, invasive arterial blood pressure, oxygen saturation, temperature, end-tidal carbon dioxide and isoflurane were recorded every 5 minutes. Arterial blood samples were taken for analysis every 30 minutes. Recovery time to recurrence of swallowing reflex, to first head movement and to standing were recorded and recovery quality was scored. Two-way repeated measures anova, Mann-Whitney and a Mantel-Cox tests were used for statistical analysis as relevant with a significance level set at p < 0.05.ResultsInduction of anaesthesia was smooth and uneventful in all goats. There was no statistical difference between groups in any measured parameter. Side effects following anaesthetic induction included slight head or limb twitching, moving forward and backward, salivation and nystagmus but were minimal. Endotracheal intubation was achieved in all goats at first or second attempt. Recovery was uneventful on all occasions. All goats were quiet and needed only one or two attempts to stand.Conclusions and clinical relevanceS-ketamine at half the dose rate of racemic ketamine in goats sedated with xylazine and thereafter anaesthetised with isoflurane induces the same clinically measurable effects.  相似文献   
990.
The effect of uncertainty on the cost-effectiveness of alternative chains of stand establishment in northern Finland was examined. The data were from a reforestation study of Scots pine (Pinus sylvestris L.) consisting of 288 sample plots, which were measured with respect to regeneration success. The study design included four site-preparation methods (patch scarification, ploughing, prescribed burning and disk trenching) combined with three reforestation methods (sowing, planting with containerized seedlings and planting with bare-rooted transplants). Initial reforestation density was 2,500 spots or seedlings per hectare, and the regeneration success was modeled as probability with two thresholds, namely 500 and 1,100 saplings. On formerly spruce-dominated as well as pine-dominated sites the most cost-effective chain was ploughing and planting with containerized seedlings, when threshold was 1,100 saplings per hectare. However, with threshold of 500 saplings the best performer was ploughing and direct sowing on both sites.  相似文献   
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