全文获取类型
收费全文 | 657篇 |
免费 | 74篇 |
国内免费 | 1篇 |
专业分类
林业 | 38篇 |
农学 | 6篇 |
基础科学 | 2篇 |
14篇 | |
综合类 | 58篇 |
农作物 | 12篇 |
水产渔业 | 26篇 |
畜牧兽医 | 546篇 |
园艺 | 5篇 |
植物保护 | 25篇 |
出版年
2020年 | 11篇 |
2018年 | 19篇 |
2017年 | 12篇 |
2016年 | 10篇 |
2015年 | 10篇 |
2014年 | 24篇 |
2013年 | 21篇 |
2012年 | 22篇 |
2011年 | 29篇 |
2010年 | 21篇 |
2009年 | 36篇 |
2008年 | 21篇 |
2007年 | 23篇 |
2006年 | 20篇 |
2005年 | 12篇 |
2004年 | 15篇 |
2003年 | 12篇 |
2002年 | 20篇 |
2001年 | 22篇 |
2000年 | 9篇 |
1999年 | 12篇 |
1998年 | 17篇 |
1997年 | 17篇 |
1996年 | 20篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1993年 | 12篇 |
1992年 | 19篇 |
1991年 | 15篇 |
1990年 | 24篇 |
1989年 | 21篇 |
1988年 | 12篇 |
1987年 | 8篇 |
1986年 | 11篇 |
1985年 | 6篇 |
1984年 | 18篇 |
1983年 | 7篇 |
1982年 | 4篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1975年 | 5篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1972年 | 9篇 |
1971年 | 10篇 |
1970年 | 5篇 |
1969年 | 8篇 |
1968年 | 4篇 |
1967年 | 5篇 |
1966年 | 3篇 |
排序方式: 共有732条查询结果,搜索用时 46 毫秒
1.
Findings are presented on the precision of a clinical biochemistry analyser designed specifically for veterinary use. Twenty biochemical analytes have been examined in detail for variation within and between runs. The results indicate that the analyser can provide high precision for all the analytes with the possible exception of calcium, and suggest that the instrument can be used with confidence in the practice laboratory to aid diagnosis and to monitor biochemical changes in animals receiving treatment. 相似文献
2.
Jeffrey R. Crass MD Ronald L. Genovese VMD James A. Render DVM Errol M. Bellon MD 《Veterinary radiology & ultrasound》1992,33(4):206-216
Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries. 相似文献
3.
George J. Brewer MD William Schall DVM Robert Dick BS Vilma Yuzbasiyan-Gurkan PhD Michael Thomas DVM George Padgett DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):41-43
Inherited canine copper toxicosis is a serious problem in Bedlington terriers and West Highland White terriers, and may also be a problem in other less-studied breeds. Affected dogs become ill at midlife with progressive and ultimately fatal liver disease. Treatments for removal of copper and prevention of copper accumulation are available, but are most effective if begun before the dog becomes ill. Until recently diagnosis has not been available until the dog is 1 year of age, and then only by an invasive liver biopsy with determination of liver copper concentration. The authors studied the use of 64copper for early diagnosis of canine copper toxicosis. Two procedures were evaluated. The first involved measuring the concentration of 64copper in blood 24 hours after oral administration of the radioisotope. At this time, 64copper was associated primarily with ceruloplasmin secreted into the blood by the liver. This procedure is useful in the diagnosis of the human counterpart, Wilson's disease. However, the authors found it to be nondiscriminatory between affected and unaffected dogs. In contrast, the second procedure, which involved measuring 64copper excreted in stool during 48 hours after an intravenous dose of radioisotope, yielded results that differentiated most affected and unaffected dogs. 相似文献
4.
D. A. Little P. van der Grinten R. H. Dwinger K. Agyemang S. Kora 《Tropical animal health and production》1991,23(2):126-132
Summary The potential for increased productivity of N'Dama cattle in response to small supplementary inputs of proteinaceous by-products
has been shown to be substantial under village husbandry conditions in The Gambia. Young N'Dama bulls were used to compare
sesame cake with cottonseed as sources of supplementary protein during the wet and early dry seasons of 1987. They were fed
0, 40, 80 or 160 g crude protein/day in these forms for four months. Supplementation significantly increased growth rate from
169 g/d in controls to means of 272 and 271 g/d for those given sesame cake and cottonseed respectively; there were no significant
differences among the supplemented groups.
During the four months of the dry season immediately after supplementation ceased all previously supplemented groups grew
significantly more rapidly than the controls (at leastP<0·05), indicating a substantial carry over effect of the supplements. Over this period the mean gain of the groups previously
given sesame cake exceeded that of those that had received cottonseed (217 cf. 158 g/d;P<0·01). The economic benefits of these responses were substantial.
Comparacion de torta de sesamo y de semilla de algodon como fuente suplementaria de proteina para terneros destetos N'Dama en Gambia
Resumen Se ha demonstrado el potencial para incrementar la productividad del ganado N'Dama, como resquesta a peque?as cantidades de insumos suplementarios de proteína, bajo condiciones de villorrio en Gambia. Se utilizaron terneros destetos N'Dama par comparar la torta de sésamo y de semilla de algodón como fuente de proteína suplementaria durate la estaicón lluviosa y principio de la seca del a?o 1987. Se les dió a los animales 0, 40, 80 o 160 g de proteína cruda/día en éstas formas durante cuatro meses. La suplementación incrementó significativamente la tasa de crecimiento, de 169 g/día en controles a 272 y 271 g/día en aquellos que recibieron torta de sésamo y de algodón respectivamente; no hubo diferenca estadística entre los grupos suplementados. Durate los cuatro meses de la estación seca inmediatamente después de que la suplementación fue suspendida, todos los grupos que habían sido suplementados crecieron sgnificativamente más rápido que los controls (P<0·05), indicando un efecto compensatorio en los suplementados. Durante ese período la media de crecimento de los grupos que recibieron torta de sésamo excedió a aquella de los que habían recibido torta de algodón (217 cf. 158 g/d;P<0·01). Los beneficios económicos de estos resultados fueron substanciales.
Comparaison entre le tourteau de sesame et la graine de coton comme sources complementaires de proteines pour les taurillons N'Dama sevres en Gambie
Résumé Le potentiel de réponse à de petites quantités supplémentaires de sous-produits proteiniques pour accroitre la productivité de bétail N'Dama, s'est révélé manifeste, dans les conditions d'élevage villageois en Gambie. De jeunes taureaux N'Dama ont été utilisés pour comparer le tourteau de sésame et la graine de coton en tant que source de complémentation protéinique pendant la saison sèche et le début de la saison humide au cours de l'année 1987. Ils ont re?u respectivement 0, 40, 80 ou 160 g de proteines brutes par jour sus ces deux formes pendat quatre mois. Cette supplémentation a accru de fa?on significative le taux de croissance, de 169 g/jour pour les témoins jusqu'à des moyennes de 272 et 271g/jour respectivement pour ceux qui ont re?u du tourteau de sésame et de la graine de coton. Quant aux groupes complémentés, il n'ont révélé aucune différence significative. Pendat les quatre mois de la saison sèche et immédiatement après l'arrêt de la supplémentation, tous les lots ayant fait précédemment l'objet d'une distribution complémentaire ont eu une croissance significativement plus rapide que les animaux témoins, du moins pourP<0,05, ce qui indique un effet important de report des suppléments. Durant cette période, le gain moyen des lots qui ont re?u le tourteau de sésame a dépassé celui des lots auxquels on a donné de la graine de coton, soit 217 g/jour contre 158 g/jour pourP<0,01. Les profits économiques de ces réponses ont été appréciables.相似文献
5.
Clifford R. Berry DVM Kathy N. Wright DVM Edward B. Breitschwerdt DVM Jerome M. Feldman MD 《Veterinary radiology & ultrasound》1993,34(1):52-55
A 13-year-old neutered female Yorkshire terrier presented with a history of progressive episodic weakness and disorientation of 4 months duration. Physical and neurologic examinations were normal at presentation. Abdominal ultrasound revealed a mass involving the right adrenal gland. Standard planar scintigraphy was performed at 4, 18, and 24 hours after intravenous injection 185 MBq (5mCi) of 123 I-labeled metaiodobenzylguanidine (123 I-MIBG). An area of focal intense uptake was identified in the area of the right adrenal gland. A pheochromocytoma was confirmed histologically after surgical excision. 相似文献
6.
7.
Linda J. Barton DVM Jennifer J. Devey DVM Steven Gorski BSt Louis Mainiero MSt Daniel DeBehnke MD FACEP 《Journal of Veterinary Emergency and Critical Care》1996,6(1):21-28
Ten, anesthetized dogs were instrumented with three pulse oximeter probes; two lingual transmittance probes and one rectal reflective probe. Arterial oxygen desaturation was produced by decreasing the inspired oxygen concentration. Hypotension was produced with an infusion of nitroprusside. Simultaneous pulse oximeter readings (SpO2 ) were compared to co-oximeter measured arterial saturation (SaO2 ) collected over a range of SaO2 (50–100%) and mean arterial pressures (40–100mmHg). Each of the monitors and means of evaluating SpO2 studied provided accurate SpO2 measurements over a range of mean arterial pressure from 40–100mmHg. All of the monitors tested tended to overestimate the SaO2 when the arterial saturation was less than 70%. 相似文献
8.
9.
Shapiro JL Rostkowski C Little PB Smith-Maxie L Julian RJ Van Dreumel AA 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(5):155-158
Caprine β-mannosidosis, a fatal inherited deficiency of the lysosomal enzyme β-mannosidase, was diagnosed in neonatal female Nubian crossbred twin kids from a small herd near Guelph, Ontario. The kids had been tetraplegic since birth, with whole body tremors, abnormal nystagmus and an intention tremor of the head. 相似文献
10.