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941.
1.Three experiments were undertaken to determine the optimum inclusion rates of field peas, faba beans, chick peas and sweet lupins in broiler starter and finisher diets in amounts up to 360 g/kg. 2. In experiment A chickens in cages grown to 21 d on diets with field peas and faba beans gave better growth rate and feed efficiency than those with sweet lupins and chick peas. Growth rate and Food conversion ratio (FCR) improved with increasing amounts of faba beans in the diet while for chick peas growth rate and FCR declined. Digesta viscosity and excreta stickiness scores were much higher on diets with sweet lupins. Steam pelleting improved growth rate and FCR on all diets. 3. In experiment B birds were in cages and grown from 21 to 42 d. There were no differences between grain legumes (when combined for all inclusions) for growth rate, food intake or FCR. Viscosity was again much higher on the sweet lupin-based diets while the pancreas was significantly enlarged on the diets with chick peas, as observed previously in chickens grown to 21 d. Steam pelleting of diets gave a consistent and positive response for weight gain and FCR. 4. Experiment C was carried out in pens each holding 60 birds under semi-commercial conditions and grown to 42 d on starter and finisher diets with the same grain legumes as used previously but each at 2 rates of inclusion similar to those in commercial practice. Field peas at 200 to 300 g/kg and chick peas at 150 to 220 g/kg gave inferior growth to faba beans (150 to 180 g/kg) and sweet lupins (120 g/kg). 5. The results of these experiments allowed tentative recommendations to be made to industry for inclusion rates of these cultivars of the 4 grain legumes. These were: field peas 300 g/kg; faba beans 200 g/kg, chick peas 100 g/kg and sweet lupins <100 g/kg. Wet droppings and high gut viscosity were serious problems with sweet lupins although these were not so obvious in experiment C. 相似文献
942.
943.
We hypothesized that the development and extinction of preferences for flavored foods paired with infusions of starch depends on the delay between food ingestion and starch administration and on the frequency of starch administration. To test this hypothesis, we divided 24 lambs into three groups of 8 lambs/group. On even days, half of the lambs were offered chopped wheat straw flavored with a distinctive flavor, whereas the other half received straw with a different flavor. Starch (12% of the daily DE required by the lambs) was infused into the rumen immediately after lambs began to eat straw in Group 1 (150 g starch), immediately after lambs began to eat straw (75 g) and 30 min later (75 g) in Group 2, and when straw refusals were collected 1 h after lambs began to eat straw in Group 3 (150 g). On odd days, the flavors were switched and infusions of starch were replaced with water. After 8 d of conditioning, starch infusions were suspended, and lambs were offered a choice of wheat straw with the two distinctive flavors. All lambs acquired strong preferences for flavored straw paired with starch (P< .001), but the delay between straw ingestion and starch infusion affected preferences (P<.05). Lambs that received starch 1 h after beginning to eat straw (Group 3) had lower preferences than lambs that received starch immediately after beginning to eat straw (Groups 1 and 2). Lambs that received two starch infusions (Group 2) did not show higher preferences for flavored straw than lambs that received only one starch infusion immediately after beginning to eat (Group 1). Lambs in our study retained preferences for at least 17 d when eating straw was no longer reinforced with starch (P<.001). However, preferences were less persistent for lambs that received starch immediately after beginning to eat straw (Group 1) than for lambs that received starch in two pulses (Group 2) or lambs that received starch 1 h after beginning to eat straw (Group 3). Collectively, our results support the hypothesis that the delay between food ingestion and starch administration affects food preferences of lambs. These findings suggest that manipulating the chemical characteristics of foods, which affects the kinetics of forage degradation in the rumen, can increase food preferences in ruminants. 相似文献
944.
Pearson GR Bazeley KJ Jones JR Gunning RF Green MJ Cookson A Woodward MJ 《The Veterinary record》1999,145(13):370-373
Escherichia coli O26:K60, with genetic attributes consistent with a potentially human enterohaemorrhagic E. coli was isolated from the faeces of an eight-month-old heifer with dysentery. Attaching and effacing lesions were identified in the colon of a similarly affected heifer examined postmortem, and shown to be associated with E. coli O26 by specific immunolabelling. 相似文献
945.
This study was conducted to determine whether young calves with maternal antibodies against bovine herpesvirus type 1 (BHV-1) but without antibodies against glycoprotein E (gE) can produce an active antibody response to gE after a BHV-1 infection. Five calves received at birth colostrum from gE-seronegative cows which had been vaccinated two or three times with an inactivated BHV-1, gE-deleted marker vaccine. After inoculation with a wild-type virulent strain of BHV-1, all the passively immunised gE-negative calves shed virus in large amounts in their nasal secretions. All the calves seroconverted to gE within two to four weeks after inoculation and then had high levels of gE antibodies for at least four months. The development of an active cell-mediated immune response was also detected by in vitro BHV-1-specific interferon-gamma assays. All the calves were latently infected, because one of them re-excreted the virus spontaneously and the other four did so after being treated with dexamethasone. The results showed that under the conditions of this work the gE-negative marker could also distinguish between passively immunised and latently infected calves. 相似文献
946.
Sloet van Oldruitenborgh-Oosterbaan MM Schipper FC Goehring LS Gremmels JF 《Tijdschrift voor diergeneeskunde》1999,124(22):679-681
In the course of several days most of the 40 riding-school horses turned out in paddocks developed ataxia of variable severity. Five of these horses showed severe ataxia and tremors, became paralyzed and were euthanized. Eleven privately-owned horses which were stabled on the same premises showed no clinical signs. The most likely diagnosis seemed to be the 'neurological form of EHV1', although the signs were not entirely typical. A few weeks later a second outbreak occurred among the riding-school horses and one of the privately-owned horses also showed signs of ataxia. In the meantime it had been shown that EHV1 titers in paired serum samples had not increased and that the cerebrospinal fluid of one of the severely affected horses was normal. Toxicological examination of hay, delivered just before the first outbreak and stored for the winter, showed a significantly increased concentration of lolitrem B mycotoxin (5-6 mg/kg). The hay appeared to have been made of ryegrass used for lawns and playing fields. Retrospectively it became probable that this hay occasionally been fed to the horses just before the onset of clinical problems. It is concluded that the horses showed the 'ryegrass-stagger syndrome'. 相似文献
947.
Twenty each of healthy lactating Friesian and Holstein cows were studied. They were of similar age and body weight, nonpregnant in their third lactation and 80–100 days post partum. The investigation was carried out for 8 weeks on two farms at the same time during the hot summer season in Egypt. The first farm was in Demietta (North east of the Nile Delta, 31° 40 N) on 20 Friesian cows and the second was in Fakous (East of the Nile Delta, 30° 40 N) on 20 Holstein cows. On each of the two farms, 10 cows were newly imported and 10 were born in Egypt.The average daily milk yield and total milk production in the third lactation of the newly imported cows were significantly higher than those of the locally born cows for both Friesians and Holsteins. At the same time, the T4, T3, urea-N, haematological values and AST enzyme activity in the newly imported cows were significantly lower than those in the locally born ones in both breeds, while the locally born cows showed significantly lower values for rectal temperature and respiration rate, as well as for AST and Alk-P enzyme activities, than the newly imported cows of either breed.Holstein cows surpassed the Friesians in milk production, as well as thyroid hormone secretion and cholesterol, haemoglobin, packed cell volume and erythrocyte count values. The opposite was found for serum total protein, urea-N and creatinine concentrations, leukocyte count and AST, ALT and Alk-P enzyme activities. 相似文献
948.
AIMS: To determine the level of agreement between transrectal ultrasonography, manual palpation and measurement of progesterone in the detection of corpora lutea in post-partum cows. To evaluate the reproductive performance of cows not detected in oestrus prior to mating, but detected with a corpus luteum at the start of mating. METHODS: Cows from seven herds which were not detected in oestrus were examined between 5 and 7 days before the herd's planned start of mating. Ovaries were examined by palpation and ultrasonography in 160 cows and plasma progesterone concentrations were also measured in 103 cows. Insemination dates and pregnancy data were recorded in 159 cows not detected in oestrus but having a corpus luteum and 1405 cycling herd mates. RESULTS: The level of agreement between ultrasonography and measurement of progesterone (kappa = 0.74) was higher than with manual palpation (kappa = 0.67) although it was significant for both techniques (p <0.001). Cows which were not detected in oestrus, but detected with a corpus luteum had a longer interval to first service (12 v. 10 days, p <0.05) and conception (19 v. 15 days, p = 0.01) than cycling herd mates and had a higher empty rate (9.7% v. 3.8%, p <0.001). CONCLUSIONS: These data indicate that ultrasonography may provide a better diagnostic tool for examining cows not detected in oestrus than manual palpation or measurement of progesterone concentration. Cows not detected in oestrus but having a corpus luteum were shown to have significantly poorer reproductive performance than cycling herd mates. 相似文献
949.
Twenty horses with central and third tarsal bone slab fractures, were treated internal fixation. Eighteen of the 20 cases were Standardbred trotters, one was a Thoroughbred racehorse and one a Swedish Warmblood. The central tarsal bone (CT) was involved in 12 cases and the third tarsal bone (T3) in 8 cases. The fractures were treated by lag screw fixation with one (18 cases) or two (2 cases) 3.5 or 4.5 mm cortical screws. Horses were confined to stall rest for one month and then put on a gradually increasing exercise programme. Convalescence time was 3-8 months until the fracture had healed and training could be resumed. Fifteen of the horses regained athletic soundness. Thirteen of the horses (72%) raced after surgery (12 Standardbreds and 1 Thoroughbred). Nine (69%) of these 13 horses won races after surgery. 相似文献
950.
Repeatability of farm average 305-day milk production and gross margin per 100 kg of milk was evaluated for 39 farms. Ranking of gross margin, its underlying factors (i.e. milk price, returns from cull cows and calves, costs of concentrates, and costs of roughage purchases per 100 kg of milk), and 305-day milk production was not completely random over the four years of the study. The coefficient of concordance ranged between 0.55 and 0.82. The costs of roughage purchased had the lowest concordance over time, and 305-day milk production had the highest concordance. For each year and each farm, the difference between average gross margin and farm-specific gross margin was calculated. The standard deviations (SD) of these values was calculated for each farm, and showed differences between farms in variability in gross margin over years (the farm-year-specific SD varied between farms from 0.56 to 5.73). All the underlying factors showed a deviation over years. So, variability of gross margin can be due to changes in all underlying factors. The impact on gross margin of purchased roughage was not of major importance because its absolute impact on the gross margin is small. We concluded that milk-production data over one year is a reliable indicator for the typical farm milk production. Because gross margin fluctuates considerably over time, however it is preferred to base economic research on data from more than one year. 相似文献