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991.
For several years, veterinary oncologists have been struggling with the prognosis of mammary tumours in dogs and cats. Translation of tumour characteristics into prognostic information is an invaluable tool for the use of the most appropriate therapies, as well as for planning innovative therapeutic trials. Moreover, canine and feline spontaneous mammary gland tumours are good models for the study of human breast cancer. Collecting and interpreting information regarding the prognosis of canine and feline mammary tumours is difficult due to the fact that different methods have been applied to study various components and characteristics. This review identifies some of the challenges of prognostic studies of spontaneous canine and feline mammary tumours and suggests standardized procedures to overcome these challenges and facilitate reproducibility and assessment of results.  相似文献   
992.
  总被引:1,自引:0,他引:1  
Three hundred 18-day-old male chicks (Arbor Acre) were divided into five groups of 60 each and given high-protein (42.28%), high-calcium (3.37%), urea-containing (5%), vitamin-A-deficient, or control diets to study the effect of nutritional imbalances on the development of nephritis and related biochemical changes over 15 weeks. The first four diets increased the levels of glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, uric acid, and nonprotein nitrogen in serum. Blood urea was increased by only the urea diet. Hypoglycemia and a decrease in hepatic glucose-6-phosphatase were also observed in chicks fed the first four diets. The vitamin-A-deficient diet resulted in a depletion of vitamin A in the liver and kidneys. These changes were directly correlated with the prolonged feeding of experimental diets and also with the severity of nephritis and degenerative changes in various organs. It was concluded that increasing the intake of nitrogen or calcium in order to increase production may in fact have the opposite effect, leading to degenerative changes in various tissues and to nephritis.  相似文献   
993.
    
Live weight development and feed expenditure were investigated on 3 levels of protein supply and isocaloric rations in scientific feeding experiments with 10 castrated male pigs each of the genetic origin land race pig X large white fed individually in the live weight range between 30 and 100 kg with a subdivision at 60 kg. In the air-dried matter the crude protein content of the feed mixtures used in the first fattening period was 17.6; 15.7 and 13.7% resp. and in the second fattening period from 60 kg live weight onwards 14.9; 12.8 and 11.4% resp. for the 3 test groups. In both fattening periods the digestibility of the rations and the N-balance were determined at 3 representative animals from each of the 3 groups. The following average live weight gains were achieved in the 3 test groups: 1st fattening period: 662; 592 and 539 g resp.; 2nd X fattening period: 709; 676 and 644 g resp. Feed expenditure over the complete fattening period was 4.2; 4.5 and 5.2 kg air-dried matter per kg live weight gain. The highest protein supply resulted in the best live weight gain performance and the lowest expenditure.  相似文献   
994.
The effects of unilateral castration (UC) and induced unilateral cryptorchidism (CR) on plasma hormones and testis anatomy were studied in 36 Holstein bulls altered at either 3, 6 or 9 mo of age (n = 12). Plasma hormone concentrations were determined in six samples collected at hourly intervals on d 0, 1, 3, 7, 14 and 30, and then at monthly intervals through 6 mo after gonadal manipulation. Although plasma testosterone (T) showed a transient decrease (P less than .05) immediately after treatment, mean plasma concentrations of luteinizing hormone (LH) and T were unaffected by UC or CR over the 6-mo period (P greater than .05). Both hormones increased (P less than .05) in concentration with advancing age. Plasma follicle stimulating hormone (FSH) concentration was greater (P less than .05) in UC than in intact (IN) bulls overall, while FSH in CR bulls did not differ (P greater than .05) from either group. At slaughter, 11 mo after gonadal alteration, mean testis weight, ratio of testis weight to body weight and mean testis sperm cell numbers were increased (P less than .05) in UC bulls compared with mean testis values in intact (IN) bulls. Unilateral castration increased (P less than .05) seminiferous tubuler diameter and seminiferous epithelial cell height from basement membrane to the border of the lumen, but did not alter the ratio of tubuler to interstitial space within the testis. Seminiferous tubuler diameter and epithelial cell height were increased (P less than .05) in CR compared with IN bulls. Unilateral gonadal alteration at 3 mo of age caused a greater (P less than .05) hypertrophy of the scrotal testis in both UC and CR bulls than alteration at 6 or 9 mo of age. Results indicate that unilateral gonadal disruption is followed by rapid compensation in testis T production, little change in systemic LH and a rapid increase in secretion of FSH in the bull within those ages investigated. Further, UC elicits a greater compensatory hypertrophy than CR and the pituitary-testis endocrine axis is more responsive to alteration at 3 mo than at 6 or 9 mo of age in the bull.  相似文献   
995.
    
OBJECTIVE: To assess the suitability of lithium dilution as a method for measuring cardiac output in anesthetized horses, compared with thermodilution and transesophageal Doppler echocardiography. ANIMALS: 6 horses (3 Thoroughbreds, 3 crossbreeds). PROCEDURE: Cardiac output was measured in 6 anesthetized horses as lithium dilution cardiac output (LiDCO), thermodilution cardiac output (TDCO), and transesophageal Doppler echocardiographic cardiac output (DopplerCO). For the LiDCO measurements, lithium chloride was administered i.v., and cardiac output was derived from the arterial lithium dilution curve. Sodium nitroprusside, phenylephrine hydrochloride, and dobutamine hydrochloride were used to alter cardiac output. Experiments were divided into 4 periods. During each period, 3 LiDCO measurements, 3 DopplerCO measurements, and 3 sets of 3 TDCO measurements were obtained. RESULTS: 70 comparisons were made between LiDCO, DopplerCO, and triplicate TDCO measurements over a range of 10 to 43 L/min. The mean (+/- SD) of the differences of LiDCO - TDCO was -0.86 +/- 2.80 L/min; LiDCO = -1.90 + 1.05 TDCO (r = 0.94). The mean of the differences of DopplerCO - TDCO was 1.82 +/- 2.67 L/min; DopplerCO = 2.36 + 0.98 TDCO (r = 0.94). The mean of the differences of LiDCO - DopplerCO was -2.68 +/- 3.01 L/min; LiDCO = -2.53 + 0.99 DopplerCO (r = 0.93). CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that lithium dilution is a suitable method for measuring cardiac output in horses. As well as being accurate, it avoids the need for pulmonary artery catheterization and is quick and safe to use. Monitoring cardiac output during anesthesia in horses may help reduce the high anesthetic mortality in this species.  相似文献   
996.
  总被引:1,自引:0,他引:1  
Body measurements on Angus- (n = 374) and Polled Hereford-sired (n = 438) calves were used to quantify calf shape via multivariate factor analysis, and measurements on Polled Hereford-sired calves were further used to investigate relationships between calf shape and sire expected progeny differences (EPD) for birth weight and first-calf calving ease. Calf birth weight, head circumference, shoulder width, hip width, heart girth, cannon bone circumference and length, and body length were recorded at 24 h postpartum. Sire birth weight EPD was positively associated (P less than .05) with all calf measures but only with head and cannon circumference after adjustment for phenotypic birth weight and gestation length. Thus, at constant birth weight, calves from higher birth weight EPD bulls tended to have larger cannon and head circumferences. Calving ease EPD was negatively related (P less than .05) to all calf measures except shoulder width. After adjustment for birth weight, only cannon circumference was associated with calving ease EPD, and this effect was removed by additional adjustment for birth weight EPD. Thus, at constant birth weight, bulls with higher EPD for calving ease sired calves with smaller cannon circumference, but at constant birth weight EPD, body measures were not associated with calving ease EPD. Factor analysis defined underlying skeletal width and frame components of shape (independent of birth weight) for both sire breeds. Calf shape differed among sires and was in part explained by birth weight EPD. No additional variation in shape was explained by calving ease EPD. Calf shape seemed to add no information for prediction of dystocia to that provided by birth weight EPD.  相似文献   
997.
A four-year-old, female neutered domestic shorthair cat had a history of chronic intermittent vomiting and lymphocytosis. B cell chronic lymphocytic leukaemia was diagnosed by flow cytometry, which revealed abnormally large numbers of mature B lymphocytes in the peripheral blood. The cat was treated conservatively with antiemetic drugs and remained stable without chemotherapy for over a year.  相似文献   
998.
Two separate analyses were carried out to understand the epidemiology of Bluetongue virus serotype 8 (BTV-8) in 2007 in North West Europe: First, the temporal change in transmission rates was compared to the evolution of temperature during that season. Second, we evaluated the spatio-temporal dynamics of newly reported outbreaks, to estimate a spatial transmission kernel. For both analyses, the approach as used before in analysing the 2006 BTV-8 epidemic had to be adapted in order to take into account the fact that the 2007 epidemic was not a newly arising epidemic, but one advancing from whereto it had already spread in 2006. We found that within the area already affected by the 2006 outbreak, the pattern of newly infected farms in 2007 cannot be explained by between-farm transmission, but rather by local re-emergence of the virus throughout that region. This indicates that persistence through winter was ubiquitous for BTV-8. Just like in 2006, we also found that the temperature at which the infection starts to spread lies close to 15 °C. Finally, we found that the shape of the transmission kernel is in line with the one from the 2006 epidemic. In conclusion, despite the substantial differences between 2006 and 2007 in temperature patterns (2006 featured a heat wave in July, whereas 2007 was more regular) and spatial epidemic extent, both the minimum temperature required for transmission and the transmission kernel were similar to those estimated for the 2006 outbreak, indicating that they are robust properties, suitable for extrapolation to other years and similar regions.  相似文献   
999.
    
On a property in the Nelson District, blood and urine samples were taken from red deer (Cervus elaphus) from which low (<1:100) antibody titres to serovar copenhageni and suspected leptospiral abortions had previously been reported. A total of 27 hinds were sampled. Microscopic agglutination test (MAT) titres in sera ranging from 1:32 to 1:128 were found in six animals. Thirteen leptospiral isolations were made from nine of the 27 urine samples. Four of these were typed as copenhageni and nine as hardjo. Two cultures were prepared from each urine sample and hardjo and copenhageni were both isolated from single urine samples from two animals. None of the 27 deer had serum MAT titres at 1:32 or above to copenhageni.  相似文献   
1000.
An ideal national resistance monitoring program should deliver a precise estimate of the resistance situation for a given combination of bacteria and antimicrobial at a low cost. To achieve this, decisions need to be made on the number of samples to be collected at each of different possible sampling points. Existing methods of sample size calculation can not be used to solve this problem, because sampling decisions do not only depend on the prevalence of resistance and sensitivity and specificity of resistance testing, but also on the prevalence of the bacteria, and test characteristics of isolation of these bacteria. Our aim was to develop a stochastic simulation model that optimized a national resistance monitoring program, taking multi-stage sampling, imperfect sensitivity and specificity of diagnostic tests, and cost-effectiveness considerations into account. The process of resistance testing of Campylobacter spp. isolated from cloacal swab samples from poultry was modeled using a Markov Chain Monte Carlo model. Different sampling scenarios on the number of flocks to be tested, the number of birds from each flock, and the number of campylobacter colonies submitted to susceptibility testing were evaluated regarding the precision of the resulting prevalence estimate. Precision of the prevalence estimate was defined as the absolute difference between apparent and true prevalence of resistance. A partial budget approach was utilized to find the most cost-effective combination of samples to obtain a defined precision of the prevalence estimate. For a sampling scenario testing 100 flocks, five birds per flock, and one campylobacter colony per sample, the median error of the prevalence estimate was 2.5%, and 95% of the simulations resulted in an error of 7% or less. When the total number of samples was kept constant, maximizing the number of flocks tested, and only testing one bird per flock resulted in the most precise prevalence estimate. Submitting more than one campylobacter colony to resistance testing did not improve the prevalence estimate. Partial budget analysis indicated that the most cost-effective strategy was testing of two birds per flock, and submitting one colony per sample to resistance testing.  相似文献   
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