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101.
Amália Turner Giannico Elaine Mayumi Ueno Gil Daniela Aparecida Ayres Garcia Marlos Gonçalves Sousa Tilde Rodrigues Froes 《Veterinary research communications》2016,40(1):11-19
The aim of this study was to develop regression models for correlation of canine fetal heart development with body size to characterize normal development or suggest cardiac anomalies. Twenty clinically healthy pregnant bitches, either brachycephalic and non-brachycephalic, were examined ultrasonographically. Transabdominal fetal echocardiography was conducted every 4 days from the beginning of cardiac chambers differentiation until parturition. Ten cardiac parameters were measured: length, width and diameter of the heart; heart area; left and right ventricular dimensions; left and right atrial dimensions; and aortic and pulmonary artery diameter. Femoral length, biparietal diameter and abdominal cross-sectional area were also recorded. Regression equations were developed for each parameter of fetal body size, and linear and logarithmic models were compared. The model with the highest correlation coefficient was chosen to produce equations to calculate relative dimensions based on the correlations. Only the left-ventricular chamber differed between the two racial groups. Biparietal diameter was the independent parameter that produced the highest correlation coefficient for the most fetal cardiac dimensions, although good correlations were also observed using femoral length and abdominal cross-sectional area. Heart width and heart diameter were used as surrogates of cardiac development, as these measurements showed the best statistical correlation. Quantitative evaluation of fetal cardiac structures can be used to monitor normal and abnormal cardiac development. 相似文献
102.
Chiara Gomiero Giulia Bertolutti Tiziana Martinello Nathalie Van Bruaene Sarah Y. Broeckx Marco Patruno Jan H. Spaas 《Veterinary research communications》2016,40(1):39-48
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate. 相似文献
103.
104.
Galina P. Simeonova Svetozar Z. Krastev Radostin S. Simeonov 《Veterinary research communications》2016,40(3-4):107-115
Background
The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.Objectives
The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.Methods
Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.Results
CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.Conclusions
Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.105.
106.
Tuntivanich N Petersen-Jones SM Steibel JP Johnson C Forcier JQ 《Veterinary ophthalmology》2007,10(1):2-5
OBJECTIVE: The objectives of this study were to document the development of axial globe length (AGL) in normal mesocephalic cross-bred dogs between 2 and 52 weeks of age, to determine a relationship between AGL and age, and derive an equation to predict AGL in normal mesocephalic cross-bred dogs. ANIMALS STUDIED AND PROCEDURE: The AGL of twenty normal mesocephalic cross-bred dogs was measured at 12 time points from 2 to 52 weeks of age using B-scan ultrasonography. RESULTS: The mean (+/- SEM) AGL increased from 12.65 mm (+/- 0.18) at 2 weeks of age to 19.52 mm (+/- 0.18) at 52 weeks of age. The correlation between AGL and age was evaluated by fitting possible variables to a regression pattern. A linear model of natural logarithmic-transformed value of AGL (mm) and age (week) was established. Side (left or right eye) and gender did not correlate with development of AGL. CONCLUSIONS: A reverse transformation of the formula can be used to predict AGL in mesocephalic cross-bred dogs: AGL = 10.847 * age in weeks 0.1653. 相似文献
107.
Iauhenia Isayenka Juan Duque-Yate Marie-Claire Goulet Dominique Michaud Carole Beaulieu Nathalie Beaudoin 《Plant pathology》2023,72(1):100-111
Potato common scab caused by the actinobacterium Streptomyces scabiei is characterized by the formation of corky lesions on tubers that reduce their marketability. Management of common scab is very complex and often ineffective under various environmental conditions. Using potato varieties that are more resistant to common scab remains one of the most efficient strategies to control this disease. However, very little is known about the factors associated with resistance to common scab. Somaclone RB9 regenerated from thaxtomin A-habituated potato Russet Burbank calli produced tubers more resistant to common scab than the original variety. Comparison of the RB9 tuber proteome with that of Russet Burbank using label-free quantitative proteomic analysis revealed changes in the accumulation of defence-related proteins from the patatin and lipoxygenase (LOX) families, which are involved in the metabolism of lipids, and of two miraculins of the Kunitz-type protease inhibitors family. The implication of LOX during common scab infection was studied using synchronized minitubers developed from leaf-bud cuttings. S. scabiei infection stimulated the accumulation of LOX in both Russet Burbank and RB9 minitubers, but this accumulation was intensified in RB9 minitubers. Infection also increased LOX activity in Russet Burbank and RB9 minitubers. However, LOX activity measured in noninfected RB9 minitubers was similar to that of infected Russet Burbank minitubers, indicating endogenous activation of LOX activity in RB9 minitubers. We discuss how increased LOX abundance and activity in the somaclone RB9 may contribute to improving tuber defence against common scab. 相似文献
108.
为探究梨火疫病菌解淀粉欧文氏菌Erwinia amylovora在全球的潜在地理分布,基于其全球分布数据和筛选得到的环境变量,利用MaxEnt模型对其在当前气候和未来气候条件下的潜在地理分布进行预测,并利用刀切法和皮尔逊相关性分析法筛选对梨火疫病菌分布有重要影响的环境变量。结果显示,对梨火疫病菌分布有重要影响的环境变量包括2月平均最高温度、1月平均降水量、7月平均最低温度、温度变化方差、昼夜温差月均值和7月平均降水量,表明春季和夏季的温度和降水对梨火疫病菌的分布有较大影响。在当前气候条件下,梨火疫病菌在全球的适生区分布较广,适生区总面积达到5.58×107 km2,且高适生区主要分布在北美洲沿海地区、地中海沿岸和亚洲中部及东部的部分地区;梨火疫病菌在我国的适生区总面积为7.36×106 km2,占全国陆地总面积的76.70%;在未来气候SSP126和SSP585情景下,梨火疫病菌在全球的适生区总面积分别为5.52×107 km2和5.24×107 km2。表明梨火疫病菌对我国大部分地区有潜在威胁,应加强监测与防控。 相似文献
109.
110.
不同驱虫药驱虫后伊犁马血液生化指标变化的研究 《畜牧与饲料科学》2023,44(1):116-121
[目的] 研究不同驱虫药对伊犁马血液生化指标的影响,为伊犁马科学驱虫及健康养殖提供参考。[方法] 将平均体重(265.5±35.6)kg、出生日期相近的40匹1岁伊犁马随机分为5组,每组8匹,分别为对照组、试验Ⅰ组、试验Ⅱ组、试验Ⅲ组和试验Ⅳ组。在相同的饲养管理和日粮营养水平条件下,对照组不驱虫,在试验开始第1天,试验Ⅰ组使用伊维菌素驱虫,试验Ⅱ组使用吡喹酮驱虫,试验Ⅲ组使用阿苯达唑驱虫,试验Ⅳ组使用伊维菌素和阿苯达唑的混合药剂驱虫;在试验第14天采集马匹血液样品,测定血浆氮代谢指标、葡萄糖及酶相关指标、脂代谢指标及金属离子指标。[结果] ①试验Ⅲ组总蛋白(TP)浓度最低,与对照组、试验Ⅰ组、试验Ⅱ组及试验Ⅳ组相比,分别降低了8.16%、7.15%、4.98%及6.62%(P>0.05)。对照组及各试验组白蛋白(ALB)、尿素(UREA)浓度均无显著(P>0.05)差异。与对照组相比,试验Ⅲ组及试验Ⅳ组血浆中UREA浓度分别降低了33.15%及36.10%(P>0.05)。②与对照组相比,试验Ⅰ组、试验Ⅱ组、试验Ⅲ组、试验Ⅳ组丙氨酸氨基转移酶(ALT)活力分别降低了26.51%、21.11%、47.14%及52.38%(P>0.05)。试验Ⅲ组血浆中碱性磷酸酶(ALP)活力低于对照组,降低了0.19%(P>0.05)。与对照组相比,试验Ⅱ组和试验Ⅳ组的乳酸脱氢酶(LDH)活力显著(P<0.05)升高,分别提高了17.84%、13.51%;谷草转氨酶(AST)活力分别提高了5.40%和4.08%(P>0.05)。③对照组血浆中甘油三酯(TG)、肌酐(CREA)及尿酸(UA)的含量与各试验组相比均无显著(P>0.05)差异。试验Ⅰ组及试验Ⅳ组血浆中CREA浓度较对照组分别提高13.38%和9.86%(P>0.05)。试验Ⅱ组血浆中胆碱酯酶(CHE)活力显著(P<0.05)高于试验Ⅲ组,提高了17.70%。④对照组血浆中Mg2+浓度与各试验组相比差异不显著(P>0.05);试验Ⅲ组血浆中Ca2+浓度最低,与对照组、试验Ⅰ组、试验Ⅱ组及试验Ⅳ组相比,分别降低了23.44%、16.40%、25.89%及21.43%(P<0.05)。[结论] 综合来看,使用伊维菌素和阿苯达唑混合驱虫,对伊犁马血浆中的氮代谢、糖脂代谢指标及肝功能代谢酶活力改善效果更明显。 相似文献