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81.
OBJECTIVE: The purpose of this study was to compare dietary practices among different birth cohorts of 70-year-old Swedes, who were examined between 1971 and 2000. SETTING: G?teborg, Sweden. DESIGN: Four population-based samples of 1360 70-year-olds, born in 1901, 1911, 1922 and 1930, have undergone health examinations and dietary assessments over a period of almost three decades. One-hour diet history (DH) interviews were conducted in 1971, 1981, 1992 and 2000 with a total of 758 women and 602 women. The formats and contents of the dietary examinations were similar over the years. Statistical analysis of linear trends was conducted, using year of examination as the independent variable, to detect secular trends in food and nutrient intakes across cohorts. RESULTS: At the 2000 examination, the majority of 70-year-olds consumed nutritionally adequate diets. Later-born cohorts consumed more yoghurt, breakfast cereals, fruit, vegetables, chicken, rice and pasta than earlier-born cohorts. Consumption of low-fat spread and milk also increased, along with that of wine, light beer and candy. In contrast, potatoes, cakes and sugar were consumed less in 2000 than in 1971. The ratio of reported energy intake to estimated basal metabolic rate did not show any systematic trend over time in women, but showed a significant upward trend in men. CONCLUSIONS: The diet history method has captured changes in food selections in the elderly without changing in general format over three decades. Dietary quality has improved in a number of ways, and these findings in the elderly are consistent with national food consumption trends in the general population.  相似文献   
82.
The association of owner-diagnosed calfhood diseases with the length of herd life after calving was evaluated using data collected prospectively over a ten-year period in 25 New York Holstein dairy herds. Herds selected for the study were milking between 35 and 200 Holstein cows, used dairy herd improvement records, bred cows by artificial insemination unless they needed three or more services, and had regularly-scheduled herd health visits by clinicians from the Cornell University College of Veterinary Medicine. Owners recorded occurrences of dullness, respiratory disease, and scours from birth through 90 days of age for all heifer calves that lived at least 24 h and were to be kept as replacements. Milking herd life was measured as the difference between the age at first calving and the age at death or sale. Data on cows sold when the herd went out of business or still in the herd at the end of the study were censored observations. Cox's proportional hazards model was used for statistical analysis of the data. Controlling for age at first calving, study month of birth, and sire predicted difference for milk, there was no statistically significant association of calfhood morbidity with length of herd life. The estimated hazard rate ratios for leaving the milking herd and 95% confidence intervals for dullness, respiratory disease, and scours within 90 days of birth were 1.3 (0.9, 1.9), 0.9 (0.6, 1.3), and 1.0 (0.8, 1.3), respectively. Dullness was the only disease category with an estimated hazard rate ratio greater than 1, and although it was not statistically significant, may warrant evaluation in future studies of long term effects of calfhood morbidity.  相似文献   
83.
Objective To develop a method for identifying DNA of Aspergillus fumigatus from ostriches, using the polymerase chain reaction (PCR). A fumigatus is the principal causative agent of avian aspergillosis.
Design A biochemical trial.
Sample population Twelve Aspergillus fumigatus isolates and three other Aspergillus species.
Procedure PCR primers that were based on the sequence of the alkaline protease gene from human isolates of A fumigatus were used.
Results We successfully tested the method on ostrich isolates from five states and showed that the test is specific for A fumigatus.
Conclusions In most cases the DNA sequence of A fumigatus isolates from ostriches is similar to that of human isolates. DNA sequences vary significantly among A fumigatus isolates, including those from affected ostriches in the same flock. The genetic variation may be used to trace aspergillus infections in ostrich flocks and determine if the disease is transmitted by contact with infected birds.  相似文献   
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85.
Some of the highest genetic merit sires have been shown to harbour recessive mutations affecting fertility, which may spread rapidly in the population through AI. These disorders may result in abortion and decline in pregnancy per insemination in cows. This study was carried out on 240 Holstein‐Friesian cows and 15 mummified foetuses. Blood and tissue samples were collected from the cows and mummified foetuses, respectively, for DNA extraction. Allele‐specific PCR was designed for the detection of the cows and foetuses carrying the nonsense mutation (C/T) in apoptosis peptide activating factor 1 gene (APAF1). The mutant allele frequency of the APAF1 in carrier cows and mummified foetuses was calculated. Milk samples were taken from the carrier and non‐carrier cows for progesterone assay. The allele‐specific PCR reaction efficiently distinguished the C/T mutation in APAF1. Of 240 cows, seven cows (2.9%) were diagnosed to carry one copy of the mutant allele of APAF1. However, the carrier frequency was 33.3% in mummified foetuses (five of 15). The mutant allele frequency was 0.02 and 0.17 in the cows and mummified foetuses, respectively. Concentrations of progesterone did not differ between cows with APAF1 mutation and non‐carrier cows during 45 days post‐insemination. This study provided allele‐specific PCR for the detection of APAF1 mutation in cows. Moreover, it reports the carrier and mutant allele frequencies of APAF1 in dairy cows and mummified foetuses in Japan.  相似文献   
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87.
Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are involved in several reproductive events like oocyte–spermatozoa interaction and semen liquefaction. In order to study their role in the llama oviductal reproductive process, MMP activity in oviductal fluid (OF) was assayed. Considering that llama genome sequences are partially known, a strategy to procure cDNA sequences of MMP‐2, MMP‐9, TIMP‐1 and TIMP‐2 was designed. Afterwards, their expression patterns in the different llama oviductal segments were assayed. Gelatine zymograms detected 62 and 94 kDa protease activities that matched MMP‐2 and pro‐MMP‐9, respectively. Expression pattern analysis showed that MMP and TIMP mRNAs were present in ampulla, isthmus, utero‐tubal junction (UTJ) and papilla. Altogether, these findings support the argument that MMPs/TIMPs are produced in the oviduct and secreted into the oviductal lumen. Our results encourage further studies to elucidate the role of these proteins in reproductive oviductal events.  相似文献   
88.
种群更新对维持种群的稳定和发展具有极其重要的意义。通过野外实地调查,对不同地区乌冈栎种群的更新情况进行了分析,结果如下:1)大多数地区乌冈栎种群的幼苗结构呈倒金字塔型,说明乌冈栎种群的更新存在一定的困难;但在乌冈栎顶级群落中,由于仍存在一定数量的幼树,短期内的更新仍能继续进行;2)从乌冈栎幼苗空间分布格局来看,林窗或林缘处呈聚集分布,而林冠下呈均匀分布,这与乌冈栎幼苗生长的需光性有极大的关系;3)乌冈栎的萌发实验表明,1~2个月的沙藏处理有利于提高萌发率,而萌发过程中鼠害和虫蛀是限制出苗率的主要原因之一;4)乌冈栎种子的传播除靠重力外,啮齿类动物对它的影响最大,他们之间存在一定的权衡关系。为了提高乌冈栎种群的天然更新率,适当干扰地开辟林窗是较佳的途径。  相似文献   
89.
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