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81.
Quantitative histology of mammary parenchymal tissue from 16 Hereford and 16 Holstein heifers was determined for tissue obtained on day 150, 180, and 280 of gestation and on day 49 of lactation. Percent area occupied by stromal tissue was progressively decreased on each consecutive sample day during gestation in Herefords and was lower in both breeds during lactation. Overall, area occupied by stromal tissue elements was also greater in Herefords. Percent lumenal space and number of cells per alveolar cross section was consistently greater for Holsteins and increased across sample periods in both breeds. During lactation more than 40% of the alveolar cells in Herefords were characterized as poorly differentiated, but in Holstein heifers nearly all of the cells were classified as either intermediate or fully differentiated. These data provide additional evidence to support the idea that much of the difference in milk production between beef and dairy animals depends on increased mammary function. Whether differences in milk production within dairy breeds are also explained by altered cellular differentiation remains to be determined. 相似文献
82.
Tonje Seim-Wikse Einar J?rundsson Ane N?dtvedt Tom Grotmol Charlotte R Bjornvad Annemarie T Kristensen Ellen Skancke 《Acta veterinaria Scandinavica》2013,55(1):25
Background
Previous research has indicated a breed predisposition to gastric carcinoma in dogs. However, results to date are inconsistent since several studies have failed to prove such a predisposition. Better knowledge of breeds at risk could facilitate early detection of gastric carcinoma in dogs. The aim of the study was to retrospectively investigate the proportion and possible breed predisposition to canine gastric carcinoma using the Norwegian Canine Cancer Register for calculations of proportional morbidity ratios (PMRs) for the period 1998–2009.Results
Histologically verified tumours recorded in the Norwegian Canine Cancer Register were studied (n = 19,715). A total of 31 (0.16%) cases of canine gastric carcinomas were identified. The median age of affected dogs was 10 years. The most commonly reported clinical signs were vomiting, anorexia, and weight loss. Males had significantly higher odds of gastric carcinoma than females (P = 0.02). The PMR with 95% confidence interval (CI) was calculated for each breed, and a breed predisposition was identified. Individuals of the breeds Tervuren (PMR 56.1), Bouvier des Flandres (PMR 36.5), Groenendael (PMR 34.5), Collie (PMR 26.1), Standard poodle (PMR 7.6), and Norwegian elkhound (PMR 6.1) had a significantly increased risk of developing gastric carcinoma.Discussion and conclusion
The proportion of cases of gastric carcinoma recorded in the Norwegian Canine Cancer Register was found to be 0.16%, and a breed predisposition was identified. The breed predisposition observed in the current study indicates a genetic susceptibility to gastric carcinoma. 相似文献83.
We provide first an overview of studies on ruminant livestock that emphasises an inter-individual variability and a relative intra-individual consistency in fear responsiveness. Then, we provide evidence that genetic factors underlie fear responsiveness. We discuss problems that may hinder the genetic evaluation and the application of fearfulness traits for genetic selection in livestock. These problems include the absence of validation in experimental designs, the complexity of fear-related responses, and the interaction between genetic factors and environmental influences that limit the consistency in fear-related responses. Some possible welfare consequences of current selection programs are also considered. Finally, we discuss the possibility for including fear criteria in current selection programs and consider how such approaches may have considerable promise in ruminant livestock. More particularly, we outline current knowledge about how genes control fearfulness. Even if fear-related responses in ruminant livestock are complex, the capacity to select on fear-related criteria or even perhaps on genes that confer fearfulness traits has the potential to significantly enhance our ability to optimise livestock for their production environment and reduce the potential for compromise to their welfare. 相似文献
84.
Egenvall A Bonnett BN Häggström J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(4):894-903
BACKGROUND: Population-based information on disease occurrence is paramount in clinical decision making and in designing preventative measures, but such information is scarce. HYPOTHESIS: The risk of cardiac death is higher in certain breeds and mortality varies by age and sex. DOGS: Dogs that were life insured by an animal insurance company between 1995 and 2002. METHODS: The mortality pattern for heart disease in insured dogs up to 10 years of age was studied. The influences of sex, age, breed, month, and geographic location were investigated by means of incidence rates, proportions, and survival proportions. Cox proportional hazards regression was used to model time to heart disease. RESULTS: 405,376 dogs contributed to a denominator of 1,431,933 dog-years at risk (DYAR) and 3,049 dogs had been assigned a cardiac-related diagnosis as cause of death. The cardiac-related mortality for dogs <10 years of age, was 21.3 deaths per 10,000 DYAR. This mortality in males and females was 27.3 deaths and 15.4 deaths per 10,000 DYAR, respectively. Twelve of 54 breeds had a point estimate above the overall rate. The 3 breeds with the highest point estimates were: Irish Wolfhounds, Cavalier King Charles Spaniels, and Great Danes (rates of 356, 247, and 179 deaths per 10,000 DYAR, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE: Breed, age, and sex affect cardiac mortality in certain breeds of dogs, but no effects of month and geographic location were identified. These findings can assist clinicians in establishing diagnoses, and can assist breeders in defining priorities for preventative measures. 相似文献
85.
S. Zhang T.J. Knight K.J. Stalder R.N. Goodwin S.M. Lonergan & D.C. Beitz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(4):259-268
The objective of this study was to estimate the effects of breed, sex, and halothane (HAL‐1843TM) genotype on fatty acid composition of triacylglycerols (TAG) and phospholipids (PL) extracted from porcine longissimus muscle (LM). Purebred Yorkshire (n = 131), Duroc (n = 136), Hampshire (n = 49), Spotted (n = 35), Chester White (n = 74), Poland China (n = 51), Berkshire (n = 169) and Landrace (n = 82) pigs (n = 727; 427 barrows and 300 gilts) from the 1994 and 2001 National Barrow Show Sire Progeny Tests were used. For statistical analyses, a mixed model was used that included fixed effects of breed, sex, HAL‐1843TM genotype, year, slaughter date within each year, interaction of breed × sex and random effects of sire and dam within breed. Breeds and sex were significantly associated with the percentages of the majority fatty acids in TAG. Duroc pigs had greater total saturated fatty acids (SFA) and lower total monounsaturated fatty acids (MUFA) (p < 0.05) contents than did pigs of all other breeds except Berkshire (p > 0.05). The concentration of total polyunsaturated fatty acids (PUFA) was the greatest in Hampshire pigs (p < 0.05). The content of total SFA was greater (p < 0.01), whereas the concentrations of total MUFA and PUFA were lower (p < 0.01) in barrows than those in gilts. The contents of major SFA in PL did not differ significantly among pigs from different breeds and sex groups. However, breed and sex significantly affected the concentrations of major MUFA and PUFA in PL and strong negative correlation between the total contents of MUFA and PUFA in PL was observed in the current study. Chester White pigs had greater total MUFA and lower total PUFA contents (p < 0.05) in PL than did pigs of all other breeds except Spotted (p > 0.05). In contrast to breed and sex effects, the concentrations of fatty acids in PL were more affected by HAL‐1843TM genotype than those in TAG. The content of C16:0, a major SFA in PL, differed significantly in pigs with different HAL‐1843TM genotypes. In conclusion, these results suggest that breed and sex are important sources of the variations for fatty acid composition of TAG and PL in LM. 相似文献
86.
猪肉品质及其影响因素的研究概况 总被引:3,自引:0,他引:3
随着猪肉生产中瘦肉率的提高,以及有害添加剂的饲喂.猪肉品质恶化。而另一方面,人们的保健意识增强,对各种畜禽肉质和风味提出了更高的要求。本文综述了常规肉品质性状,以及品种和营养对它的影响。 相似文献
87.
88.
子宫蓄脓症是一种常见的母犬生殖系统疾病,为提高宠主对此病的重视及早期诊断提供帮助,文章收集了2017~2018年重庆8家动物医院的162例病例,分析子宫蓄脓症的发生与品种、年龄、生育史等之间的关系.结果 可见:从犬种上看,常见患犬为北京犬27.78%,吉娃娃12.96%,博美11.11%;从体型上看,小型犬的发病率较高... 相似文献
89.
特种木匆心 木菜含多种人体需要的氨基酸 ,营养丰富 ,风味独特 ,药用保健价值高 ,其植株含皂甙 2 0 4 % ,是人参的 2 5倍。野生资源少 ,国内外市场紧俏。为了解决规模生产 ,供应市场 ,特进行人工栽培技术研究。试验初步结果显示 ,用野生植株的枝条、根系、种子均能繁殖 ,在露地、大棚均能栽培 ,可以发展规模生产。 相似文献
90.
An epidemiological study with the objective to assess the prevalence of paramphistomosis in association with season, age,
sex and breed was carried out in naturally infected sheep over a period of two years from February 2005 to January 2007. Gastrointestinal
tract (GIT) and faecal examination were conducted monthly to monitor the seasonal occurrence of paramphistomosis. 793 sheep
were examined in the first year, out of which 7.06% were positive for Paramphistomum infection. In the second year, 740 animals were investigated and 7.7% were infected. The overall prevalence of paramphistomosis
was 7.3% with a mean of 56.50 ± 0.50 and 95% confidence interval (CI) (lower bound: 50.1469; upper bound: 62.8531). The prevalence
of paramphistomosis through GIT examination (P = 0.593) was 7.6% at 95% CI (lower bound: −19.1186; upper bound: 57.1186) and the prevalence through faecal examination (P = 0.884) was 7.2% at 95% CI (lower bound: 5.7345; upper bound: 69.2655). Generally, season and age were the factors found
to have a significant influence on the risk of paramphistomosis in sheep. The highest infection was found in the summer season
(P < 0.005); lower age groups (P < 0.005) in males and in migratory (Bhakarwal) breed (P ≥ 0.005). Winter, adult animals, females and local breed reported low infection. The present study will be of great significance
to understand the epidemiology of gastrointestinal helminthes of sheep initially in the resource poor communities of Himalayan
region and will definitely be helpful to devise appropriate control strategies for paramphistomosis. 相似文献