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11.
本试验旨在通过研究饲喂氧化鱼油对新生仔猪生长性能、肠道黏膜氧化相关指标、免疫因子、氧化和免疫共同相关因子的影响以及添加大豆异黄酮(SI)对其的干预作用,探讨氧化应激对新生仔猪生长、肠道免疫应答的影响机制.试验选用4日龄新生仔猪96头,分成4组,每组6个重复,每个重复4头仔猪,各组饲粮中分别添加5%新鲜鱼油(Ⅰ组)、5%...  相似文献   
12.
The ultrasonographic appearance and size of the liver and kidneys of a litter of five pups was examined from birth until six months of age, and compared with a group of five adults of the same breed. Increased renal cortical echogenicity was evident for the first two weeks of life. Up to 12 weeks of age renal size was relatively large in comparison with body size parameters. After 12 weeks measures of renal size were proportionate with body size and were not significantly different from adult dogs. The neonatal liver had a similar ultrasonographic appearance to the adult, although in the first eight weeks parenchymal echogenic stippling was less coarse and portal veins were less well delineated. Measures of hepatic length were inaccurate during the first four weeks after birth due to changes in body conformation. From eight weeks to six months of age these measures were proportionate with body size, although the ratios differed from adult dogs.  相似文献   
13.
This review summarizes the results of a study on rotaviruses isolated from calves affected by neonatal diarrhea.

The results indicated that rotavirus infection is widespread and supported the evidence for an etiologic role of these viruses in neonatal diarrhea. Differences in virulence among bovine rotaviruses appeared also to be confirmed.

Conventionally reared calves were fully susceptible to the experimental infection induced by rotaviruses originating from heterologous hosts, i.e. monkeys, pigs and rabbits.

When rotavirus strains of bovine, simian and rabbit origin were compared by cross neutralization tests, it was found the simian and porcine strains were indistinguishable and both appeared to relate antigenically to the bovine strain.

Finally, it was proven that feeding newborn calves with colostrum and first milk of their dams, previously vaccinated with an inactivated adjuvanted rotavirus vaccine, could prevent the neonatal diarrhea from occurring.  相似文献   

14.
Objective – To investigate the association between blood lactate concentration, measured at admission and following 12–36 hours of treatment, and age, diagnosis, and survival in neonatal foals. Design – Retrospective, observational study. Setting – Two equine referral hospitals. Animals – One hundred and twelve foals ≤96 hours of age were included. Interventions – Arterial or venous blood samples were obtained from all foals at admission and surviving foals at 12–36 hours. Measurements – The lactate concentration (LAC) was recorded at 2 time points: admission (LAC‐Admission) and 12–36 hours following treatment (LAC‐24 hours). Main Results – LAC decreased by 0.05 mmol/L for each increased hour of age at presentation. Premature/dysmature foals demonstrated increased odds of nonsurvival of 55% for each 1 mmol/L increase in LAC‐Admission while foals with major diagnoses of neonatal encephalopathy (NE), enteritis and ‘Other’ had increased odds of nonsurvival of 52%, 113%, and 247%, respectively, for each 1.0 mmol/L increase in LAC. Blood‐culture positive foals had significantly lower LAC than blood culture negative foals. LAC‐Admission and LAC‐24 hours were significantly larger in nonsurviving foals. LAC‐Admission of >6.9 mmol/L and LAC‐24 hours >3.2 mmol/L, respectively, correctly classified 85.6% and 94.1% of cases as survivors or nonsurvivors. No differences were found when the 24‐hour change in LAC was investigated in terms of outcome, age at admission, or major diagnosis; however, LAC‐24 hours remained significantly associated with survival. Conclusions – Admission or persistent hyperlactatemia is associated with a nonsurvival. Younger foals, premature/dysmature foals, and foals with neonatal encephalopathy had the largest LAC.  相似文献   
15.
An observational study was conducted to comparatively assess the efficacy of three different oral rehydration and buffering solutions, differentiated by their strong ion difference (SID) concentration, for treatment of neonatal calves with naturally acquired diarrhea. The SID concentrations tested were 100 mM, 170 mM and 230 mM for treatments SID100, SID170 and SID230, respectively. Clinical assessment and blood gas analysis were completed for 18 diarrheic calves once pre- and twice post- (6 and 24 hr after) oral administration with one of the three treatments. A repeated measure mixed model approach was used to analyze (a) the within-group efficacy of each treatment over time and (b) the between-group comparison at each timepoint. SID230 treatment resulted in a significant increase in blood pH, HCO3, BE, SID and Na+ at 6 and 24 hr after treatment, and a significant decrease in AG and K+ by 24 hr after treatment. There were no significant changes in any of the blood gas parameters after treatment with SID100 and SID170. SID230 treatment also resulted in blood gas parameter changes that were significantly different to the other two groups. These results suggest that the optimum SID concentration for the treatment of calves with diarrhea is likely to be higher than current recommendations.  相似文献   
16.
Objectives – To review the principles and available technology for pretransfusion testing in veterinary medicine and discuss the indications and importance of test performance before RBC transfusion.
Data Sources – Current human and veterinary medical literature: original research articles and scientific reviews.
Summary – Indications for RBC transfusion in veterinary medicine include severe anemia or tissue hypoxia resulting from blood loss, decreased erythrocyte production, and hemolyzing conditions such as immune-mediated anemia and neonatal isoerythrolysis. Proper blood sample collection, handling, and identification are imperative for high-quality pretransfusion testing. Point-of-care blood typing methods including both typing cards and rapid gel agglutination are readily available for some species. Following blood typing, crossmatching is performed on one or more donor units of appropriate blood type. As an alternative to technically demanding tube crossmatching methods, a point-of-care gel agglutination method has recently become available for use in dogs and cats. Crossmatching reduces the risk of hemolytic transfusion reactions but does not completely eliminate the risk of other types of transfusion reactions in veterinary patients, and for this reason, all transfusion reactions should be appropriately documented and investigated.
Conclusion – The administration of blood products is a resource-intensive function of veterinary medicine and optimizing patient safety in transfusion medicine is multifaceted. Adverse reactions can be life threatening. Appropriate donor screening and collection combined with pretransfusion testing decreases the occurrence of incompatible transfusion reactions.  相似文献   
17.
Recently, we reported that intracerebroventricular (i.c.v.) injection of reduced glutathione (GSH) induces hypnotic and sedative effects under an acute stressful condition in chicks. However, no information is available on the effects of GSH on energy expenditure (EE) under stressful conditions. The purpose of the present study was to clarify whether i.c.v. injection of GSH affects EE of neonatal chicks, and whether EE is correlated with behavioral changes after isolation-induced stress. The EE was rapidly decreased by i.c.v. injection of GSH, but was increased 27 min after injection. This change in EE was correlated with behavioral changes in which GSH induced hypnotic and sedative effects shortly after injection, followed by a period in which activity increased. The present study demonstrates that central GSH initially causes lowered EE through hypnotic and sedative effects under an acute stressful condition in chicks.  相似文献   
18.
为研究日粮中添加γ-氨基丁酸对热应激大鼠子代发育和抗氧化功能的影响,选用90日龄的Sprague-Dawley大鼠52只(雌性大鼠39只,雄性13只)进行试验,交配后27只受孕雌鼠随机分为三组,正常对照组,热应激组和GABA热应激组,仔鼠出生后1天,测定发育指标和肝脏抗氧化指标。结果显示,与正常对照组相比,热应激组新生雌鼠和雄鼠的尾长均显著降低(P<0.01);新生大鼠的肝脏谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性有所降低,丙二醛(MDA)含量有所升高,但差异均不显著。与热应激组相比,GABA热应激组新生雌鼠(P<0.01)和雄鼠(P<0.05)的尾长均显著提高;新生大鼠的肝脏MDA含量有所降低,GSH-Px、SOD活性有所升高,但差异均不显著。结果提示GABA一定程度上可改善孕期热应激条件下新生大鼠的抗应激能力。  相似文献   
19.
Cytokines produced by T helper (Th) cells are important in orchestrating the immune response during health and disease. Recent reports indicated that cytokine mRNA expression in foals is often quantitatively lower than that of adult horses suggesting that foal T cells are not fully mature. Here, peripheral blood mononuclear cells from foals and adult horses were stimulated with phorbol 12-myristate 13-acetate and analyzed for intracellular interferon-gamma (IFN-γ), interleukin-4 (IL-4) and IL-10 production, representing the Th1, Th2 and regulatory TR1 cell phenotypes respectively, by flow cytometry. In agreement with previous reports, all three cytokines were quantitatively reduced in foals compared to adults. However, the balance between Th1 and Th2 cytokines (IFN-γ/IL-4 ratio) showed a clear Th1-biased response in foals by 6 and 12 weeks of life, while similar IFN-γ/IL-10 ratios were found in foals and adult horses. By day 5 after birth, intracellular IFN-γ production by foal CD4+ and CD8+ T cells resembled that in adults. Overall, IL-4 production was low in foals. IL-4+ cells peaked at day 5 of age when IL-4 was mainly produced by IgE+ cells. Relative percentages of IL-4+ Th2 cells were significantly lower in foals at all time points. The data suggested that equine neonates and young foals have an impaired Th2 response, that the immune response of foals is Th1 biased, that IFN-γ production by Th and cytotoxic T cells is qualitatively similar to adult horses, and regulatory IL-10 production by T cells is developmentally mature in foals during the first three months of life.  相似文献   
20.
目的探讨欣普贝生联合地西泮静脉推注用于足月妊娠引产的临床效果及母婴安全性。方法采用随机对照前瞻性研究方法,对正常单胎头位初产妇足月妊娠。宫颈评分小于6分,无瘢痕子宫,具有引产指征而无使用前列腺素禁忌症的孕妇100例,随机分成观察组50例和对照组50例,观察组阴道放人欣普贝生,有不规律宫缩时静推地西泮10mg,对照组阴道放人欣普贝生,用药12h观察用药前后宫颈Bishop评分变化及用药至分娩时问、阴道分娩率、剖宫产率、总产程、产后24h出血量和新生儿体重、Apgar评分及出现子宫过度刺激等情况的差异。结果观察组用药促宫颈成熟有效率(98%)明显高于对照组(72%)(P〈0.05);观察组总产程平均为468min,阴道分娩成功率占82%,对照组总产程平均648min,阴道分娩成功率66%,两组差异有显著性(P〈0.05);产后出血量、新生儿Apgar评分、新生儿体重两组差异无显著性。结论欣普贝生联合应用地西泮对足月妊娠引产安全有效。  相似文献   
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