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41.
Identification of the duodenum and potential abnormalities on survey abdominal radiographs is often difficult unless it contains gas. This study investigated the effect of patient positioning on the presence of duodenal gas in survey abdominal radiographs. One hundred dogs receiving a three‐view survey abdominal radiographic study were enrolled in a prospective, randomized study where all dogs were divided into two groups. Group A (n = 51) dogs had a left lateral projection first, followed by a ventrodorsal projection, ending with a right lateral projection. Group B (n = 49) dogs had a right lateral projection first, followed by a ventrodorsal projection, ending with a left lateral projection. The presence of gas within the duodenum and level of distribution of gas throughout the duodenum were recorded for all three projections. In addition, the presence or absence of duodenal pseudoulcers was evaluated on all three projections for each dog. The results for the two groups were compared using Chi‐square analysis with a P‐value of less than 0.05 being considered significant. Results showed that dogs first placed in left lateral recumbency were significantly more likely to have duodenal gas on the subsequent ventrodorsal and right lateral radiographic projections compared to dogs first placed in right lateral recumbency (P‐value < 0.0001). Pseudoulcers were seen in 11 dogs that had duodenal gas making the visualization of pseudoulcers on survey abdominal radiographs somewhat commonplace. This study emphasizes the benefit of using initial left lateral abdominal projections prior to other views for subsequent evaluation of the duodenum.  相似文献   
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43.
猪十二指肠中生长抑素阳性细胞和免疫细胞发育的研究   总被引:3,自引:0,他引:3  
应用免疫组织化学技术分别研究猪十二指肠生长发育过程中生长抑素(SS)阳性细胞、IgA阳性细胞和酸性非特异性脂酶(ANAE)阳性细胞数量的变化。结果表明,SS阳性细胞的发育模式与IgA阳性细胞和AENE阳性细胞的呈相反趋势。SS阳性细胞数量于3日龄开始增加,20日龄达到第一个高峰,然后于45日龄呈极显著降低(P<0 01),90日龄又呈显著上升趋势(P<0 05),至120日龄时又达到第二个高峰;从出生至3日龄猪十二指肠无IgA阳性细胞的分布,20日龄时IgA阳性细胞开始出现,45日龄IgA阳性细胞数量显著增加(P<0 05)并达最高峰,90日龄时又呈下降趋势;猪十二指肠AENE阳性细胞数量在3日龄及20日龄均极显著增加(P<0 01)。然后于45日龄开始显著减少(P<0 05)。结果表明猪十二指肠中SS阳性细胞的发育对免疫细胞的发育可能具有重要的调节作用。  相似文献   
44.
Vagally-mediated regulation of motility in the abomasal body by duodenal and abomasal antral motility was demonstrated in acutely prepared anaesthetized sheep. The enteric plexuses between the abomasal body, antrum and duodenum were interrupted by transection. Antral contractions were more effective than duodenal contractions at causing inhibition of the abomasal body, and antral isometric conditions were more effective than antral isotonic conditions. Inhibition of motility in the abomasal body was reduced by unilateral cervical vagotomy, was abolished by bilateral cervical vagotomy, and was reversibly inhibited by cervical vagus cold block. The demonstration of vagal pathways in abomaso-abomasal reflexes confirms a functional homology of the mechanisms in the ruminant and animals with simple forms of stomach.Abbreviations b-t balloon-tipped - EMG electromyography - NANC non-adrenergic, non-cholinergic - o-t open-tipped  相似文献   
45.
Six sheep were equipped with both a rumen fistula and a duodenal cannula. The duodenal cannula was made of two ordinary T shape cannulas which were vulcanized into a double T cannula. Both the rumen and the duodenal cannulas were made of soft rubber.In two experiments six different diets were fed. In the first experiment the diets consisted mainly of ammonia-treated straw (NH3-straw) plus barley or sodium hydroxide-treated straw (NaOH-straw) plus concentrate containing different N-supplements. In the second experiment, the treated straw (either NH3-straw or NaOH-straw) was fed alone. The animals in the two experiments were fed at maintenance level.Duodenal digesta were collected for periods of 12 h by inflating a balloon in the distal flange of the cannula, using pieces of foam rubber. The volume of fluid leaving the rumen was measured using the marker Gr-EDTA. The effect of digesta removal on blood constituents was studied. Three to four observations on each ration were made.Digesta flow and dry matter entering the duodenum were higher with NH3-straw than NaOH-straw fed either alone or with concentrate. However, there was a considerable variation of which a large part was of individual nature.The volume of fluid reaching the duodenum was always lower than the volume leaving the rumen, indicating a net absorption of water in the omasum and abomasum. This was estimated to be from 10.1 to 11.6 1/24 h in Experiment 1 and from 0.3 to 1.4 1/24 h in Experiment 2 (51–59 and 5–31 % of the ruminai outflow, respectively).A significant increase in plasma K and Mg and decrease in Pi and a-amino N concentration were observed due to 12 h collection of duodenal digesta. However, plasma Na, Ca, glucose and urea nitrogen concentrations remained at their pre-collection levels.Post-mortem examination of duodenum in sheep slaughtered after six and 10 months revealed a normal gut with no sign of dilatation in the immediate vicinity of the cannula.  相似文献   
46.
In 13 anaesthetized hens in the peak phase of their first laying year the influence of intravenously injected substance P (SP), 1–10 g/animal, on oviductal pressure, duodenal pressure, blood pressure and heart rate has been studied within 5 h of oviposition. The neuropeptide induced a significant pressure increase in the different segments of the oviduct (infundibulum, magnum, isthmus, uterus and vagina) as well as in the duodenum. Blood pressure revealed a distinct biphasic response: a short period of hypotension accompanied by a tachycardia and a more pronounced and sustained hypertension, inducing a subsequent bradycardia. The complexity of the observed effects demonstrates the overall impact of intravenously administered SP on the anaesthetized hen.  相似文献   
47.
Light microscopy was undertaken on sections from the caudal flexure of the duodenum and the terminal ileum proximal to the ileocaecal fold in 5 control horses, 5 horses with acute grass sickness (AGS), and 5 horses with chronic grass sickness (CGS). With the exception of the ileal submucous plexus of the CGS group, the AGS group had the lowest number of neurons as measured using a subjective scoring scheme. The proportion of abnormal neurons in the AGS group was similar in both plexuses and both regions, whereas the values for the CGS group were much higher in the duodenal region than in the ileal region. The motility of tissue adjacent to that used for histology was measured isometrically in vitro. The increase in the rate of contractions following exposure to physostigmine was greatest for the AGS group, both from the duodenal and from the ileal region. The latency was longest for the AGS group, suggesting that the material from this group had the least number of active cholinergic neurons. The studies with physostigmine thus indicated that the most severe functional damage occurred in cases of AGS. These findings confirm that extensive damage occurs in the enteric neurons in equine grass sickness. There was good correlation between the functional cholinergic responses and the extent of neuronal degeneration.  相似文献   
48.
为了研究固始鸡十二指肠的生长发育规律和组织学特点,应用大体解剖学和组织切片技术,对0~20周龄父母代固始鸡的十二指肠进行了发育形态学研究,并用Logistic方程模型模拟十二指肠质量的生长变化。结果表明,随着周龄的增加,固始鸡十二指肠的长度、质量、周长、绒毛长度、肠腺隐窝深度、肠腺宽度及各肌层厚度均增大;十二指肠相对生长率、十二指肠指数和肠腺密度均呈下降趋势;肠绒毛有分支现象;淋巴组织的发育比较缓慢,到6周龄后才出现有淋巴小结。  相似文献   
49.
【目的】研究银杏叶提取物(EGB)对肉仔鸡十二指肠黏膜的免疫调节作用。【方法】将360只1日龄健康AA肉用母雏鸡随机分成5组,每组6个重复,其中1组为对照组,饲喂基础日粮;其余4组分别饲喂添加质量分数0.009%金霉素及0.15%,0.20%和0.25%EGB的日粮,试验期为42d。分别于21和42d取样,测定各组肉仔鸡十二指肠黏膜免疫球蛋白含量、黏膜免疫相关细胞数量和白细胞介素-2(IL-2)含量。【结果】日粮中添加质量分数0.20%,0.25%EGB可显著提高42日龄肉仔鸡十二指肠黏膜IgA、IgG、IgM含量(P<0.05),提高十二指肠上皮内淋巴细胞、肥大细胞、杯状细胞数量和IL-2含量(P<0.05),并且作用效果优于金霉素组(P<0.05)。【结论】日粮中添加质量分数0.20%或0.25%EGB,可增强肉仔鸡十二指肠黏膜免疫功能。  相似文献   
50.
试验旨在分析鸭瘟病毒(duck plague virus,DPV)感染樱桃谷鸭后十二指肠黏膜转录组水平的变化,筛选出DPV感染后参与炎症的相关基因和调控通路。DEV-GZ株经腿部肌肉接种35日龄鸭后,于接种后24、48和72 h采集鸭十二指肠黏膜组织样本,提取总RNA进行转录组测序,对数据进行质控与注释,筛选与炎症相关的差异表达基因及调控通路,并应用实时荧光定量PCR对部分差异表达基因进行验证。结果显示,对照组与试验组总计得到21.39 Gb的Clean Bases,测序样本有效序列占原始序列的99%以上,映射率高于83%。鸭接毒DPV后24 h十二指肠黏膜的差异表达基因有221个,参与炎症相关生物学过程的有3个,均为下调基因;接毒DPV后48 h差异表达基因有499个,参与炎症相关生物学过程的有17个,均为下调基因;接毒DPV后72 h差异表达基因有798个,参与炎症相关生物学过程的有20个,其中上调基因13个、下调基因7个。GO数据库分析显示,参与炎症相关的差异表达基因主要是CCR8、CCL19、CCL4、IL-17、IRF1、IFN-γSLC11A1等,涉及急性炎症反应、趋化因子受体活性、急性期反应、炎症反应和炎症反应的正调节等生物学过程。KEGG数据库分析显示,差异表达炎症相关基因主要富集在Toll样受体信号通路、NF-κB信号通路、IL-17信号通路、TNF信号通路和炎症性肠病等;实时荧光定量PCR结果显示,IFN-γMALT基因的相对表达倍数与转录组结果基本一致。本试验完成了DPV感染樱桃谷鸭十二指肠的转录组测序分析,获取了差异表达基因的功能注释信息,初步揭示了参与DPV感染的炎症相关通路,为深入探究DPV的致病机制提供了理论参考。  相似文献   
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