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961.
A total of 39 Holstein cattle were grazed in tracts of wild grassland on account of shortage in pasture grass. Twenty-nine cattle were affected and 26 of them died during a 21-day period. The main signs were depression, anorexia, ascites, and oliguria. There was elevated serum urea nitrogen and sugar and protein in the urine. Pathological examination revealed turbid swelling of the kidney, an increase in the amount of fluid in the body cavity, edema in the perirenal adipose tissue and hemorrhage in various visceral organs and tissues. Histologically, acute tubular necrosis in the kidney, hypoplasia of the erythroblast series in the bone marrow, atrophy and degeneration of the lymphatic tissue and focal necrosis of the liver were observed in many of the cattle. Among cows experimentally fed Narthecium asiaticum Maxim., Polygonum sachalinense Fr. Schum., and Vitis coignetiae Pulliat which were presumed to have been ingested in large amounts by grazing cattle in the field, the cows fed N. asiaticum revealed the clinical, biochemical and pathological changes similar to those noticed in naturally affected cattle. Cows fed P. sachalinense and V. coignetiae showed no distinct systemic symptoms except transient anorexia and hypothermia.  相似文献   
962.
A surgical technique was devised to collect rete testis fluid from 14 mature goats. The tubular portion of the extratesticular rete testis was cannulated where it penetrated the tunica albuginea of the testis under the center of the head of the epididymis. The tip of the cannula was sutured in place in the extratesticular rete testis and the opposite end was passed through the scrotum and into a plastic collection bottle. The bottle was glued to pillow ticking, which was sutured to the scrotum. Continuous flow of rete testis fluid occurred for 0 to 14 days and was usually terminated by a sperm clot in the cannula. The flow rate was 0.59 +/- 0.37 ml/hr.  相似文献   
963.
964.
A total of 269 steers produced in a four-breed diallel mating design of Simmental, Limousin, Polled Hereford, and Brahman breeds were evaluated for the unadjusted and maintenance-adjusted total feed intake to total weight gain ratio. Time on feed ranged from 184 to 251 d. Covariate adjustments were made separately for age- and 12th rib fat-constant end points. Purebred, general combining ability, and maternal effects and heterosis were estimated. Effects of year, breed of dam, slaughter group, and days on feed accounted for most of the variation in feed conversion. Significantly higher unadjusted cumulative feed/gain ratios were found for steers from Brahman sires and for those from Simmental, Limousin, and Brahman dams. Adjustment to either fat- or age-constant values did not rerank breed groups, but a small reduction in the differences between these groups was detected for fat-constant efficiency. For maintenance-adjusted feed intake, progeny of Simmental and Limousin dams were less efficient than those of Polled Hereford and Brahman dams. Negative values for general combining ability, maternal effects, and heterosis would indicate less feed required per unit of weight gain. General combining ability for Polled Hereford crosses was negative and significant for cumulative feed/gain ratios, but no difference among dam breeds was found for the maintenance-adjusted ratio. Maternal effects for Limousin dams were positive and significant for all maintenance-adjusted ratios. Heterosis estimates for specific breed crosses were generally negative and ranged from -.87 to .22.  相似文献   
965.
Grass awn migration in dogs and cats: a retrospective study of 182 cases   总被引:3,自引:0,他引:3  
A retrospective study of 182 cases of grass awn migration in dogs and cats seen during a 1-year period was performed. The 182 cases comprised 61% of all foreign body-related cases during that year. Compared with the total hospital population, there was an increased prevalence of grass awn problems in the Springer Spaniel, Golden Retriever, Brittany Spaniel, and Airedale Terrier, but a decreased prevalence in German Shepherd Dogs, Miniature Poodles, and Dachshunds. The most common site of grass awn localization was the external ear canal, involving 51% of grass awn cases. Other common sites of grass awn localization included the interdigital webs, eye, nose, lumbar area, and thoracic cavity. Only 8 of the 182 animals were cats and 7 of the 8 had ocular involvement.  相似文献   
966.
Bullous pemphigoid (BP) is an autoimmune subepithelial blistering dermatosis of humans, dogs, cats and pigs. It is characterized by skin-fixed and circulating IgG autoantibodies that target one or both BP antigens. An immunological homologue of BP in humans was diagnosed in two horses with cutaneous and mucosal ulcerations as well as microscopic subepithelial vesiculation. Immunological investigations revealed similar findings for both the horses. Direct immunofluorescence demonstrated the presence of IgG deposited linearly at the dermoepidermal junction in mucosal and skin biopsy specimens. Indirect immunofluorescence testing confirmed the existence of circulating basement membrane-specific IgG autoantibodies. Using intact and salt-split epithelial substrates, serum IgG were shown to target antigens situated not only at the basal, but also at the lateral and apical aspects of stratum basale keratinocytes. Immunoblotting and ELISA corroborated that the IgG from affected horses, but not those from normal controls, exhibited high immunoreactivity against the NC16A extracellular domain of type XVII collagen (BPAG2, BP180). Equine BP could be proposed, therefore, as another spontaneous model of this most common basement membrane autoimmune dermatosis of humans.  相似文献   
967.
Based on favorable experiences with acupuncture for the treatment of hind limbs paralysis, lumbo-sacral alterations, and other spinal cord problems; a clinical trial, involving 40 dogs affected with wobbler syndrome was carried out. Patients were graded in three categories according to the severity of each case and then randomly divided in two groups. Both groups contained all three grades. Group 1 (20 dogs) was treated using orthodox medical and surgical interventions, while Group 2 (20 dogs) were treated mainly with electroacupuncture, and in few cases with surgical intervention as well. The study was carried out in a three-year period. Acupuncture treatments were given every other day delivering 150 to 300 mVolts at 125 Hz, equivalents to approximately 20 microAmps, in ten acupuncture points per treatment. Deep needle insertion was used. Overall per cent success in Group I was only 20%, while in group II the corresponding value was 85%. The number of acupuncture treatments required to achieve full recovery in Group II was dependent upon the severity of the case, as follows: Grade I: 18.5 +/- 2.5; Grade II: 25 +/- 5.4; and Grade III: 34 +/- 6.7 (r = 0.962). No adverse effects were observed with acupuncture. The use of this technique is proposed for large-scale clinical trials.  相似文献   
968.
969.
OBJECTIVE: To evaluate in vitro holding power and associated microstructural and thermal damage from placement of positive-profile transfixation pins in the diaphysis and metaphysis of the equine third metacarpal bone. SAMPLE POPULATION: Third metacarpal bones from 30 pairs of adult equine cadavers. PROCEDURE: Centrally threaded positive-profile transfixation pins were placed in the diaphysis of 1 metacarpal bone and the metaphysis of the opposite metacarpal bone of 15 pairs of bones. Tensile force at failure for axial extraction was measured with a materials testing system. An additional 15 pairs of metacarpal bones were tested similarly following cyclic loading. Microstructural damage was evaluated via scanning electron microscopy in another 6 pairs of metacarpal bones, 2 pairs in each of the following 3 groups: metacarpal bones with tapped holes and without transfixation pin placement, metacarpal bones following transfixation pin placement, and metacarpal bones following transfixation pin placement and cyclic loading. Temperature of the hardware was measured with a surface thermocouple in 12 additional metacarpal bones warmed to 38 C. RESULTS: The diaphysis provided significantly greater resistance to axial extraction than the metaphysis. There were no significant temperature differences between diaphyseal and metaphyseal placement. Microstructural damage was limited to occasional microfractures seen only in cortical bone of diaphyseal and metaphyseal locations. Microfractures originated during drilling and tapping but did not worsen following transfixation pin placement or cyclic loading. CONCLUSIONS AND CLINICAL RELEVANCE: Centrally threaded, positive-profile transfixation pins have greater resistance to axial extraction in the diaphysis than in the metaphysis of equine third metacarpal bone in vitro. This information may be used to create more stable external skeletal fixation in horses with fractures.  相似文献   
970.
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   
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