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41.
Background: Contrast videofluoroscopy is the imaging technique of choice for evaluating dysphagic dogs. In people, body position alters the outcome of videofluoroscopic assessment of swallowing.
Hypothesis/Objective: That esophageal transit in dogs, as measured by a barium esophagram, is not affected by body position.
Animals: Healthy dogs ( n = 15).
Methods: Interventional, experimental study. A restraint device was built to facilitate imaging of dogs in sternal recumbancy. Each dog underwent videofluoroscopy during swallowing of liquid barium and barium-soaked kibble in sternal and lateral recumbancy. Timing of swallowing, pharyngeal constriction ratio, esophageal transit time, and number of esophageal peristaltic waves were compared among body positions.
Results: Transit time in the cervical esophagus (cm/s) was significantly delayed when dogs were in lateral recumbency for both liquid (2.58 ± 1.98 versus 7.23 ± 3.11; P = .001) and kibble (4.44 ± 2.02 versus 8.92 ± 4.80; P = .002). In lateral recumbency, 52 ± 22% of liquid and 73 ± 23% of kibble swallows stimulated primary esophageal peristalsis. In sternal recumbency, 77 ± 24% of liquid ( P = .01 versus lateral) and 89 ± 16% of kibble ( P = .01 versus lateral) swallows stimulated primary esophageal peristalsis. Other variables were not significantly different.
Conclusions and Clinical Importance: Lateral body positioning significantly increases cervical esophageal transit time and affects the type of peristaltic wave generated by a swallow.  相似文献   
42.
Background: Eosinophilic inflammation of the gastrointestinal tract of dogs occurs in numerous disorders, typically resulting in diffuse intestinal thickening. Rarely, eosinophilic masses have been reported.
Objective: Describe a series of dogs with 1 or more idiopathic eosinophilic gastrointestinal masses (IEGM) to better characterize the clinical features, treatment, and prognosis.
Animals: Seven dogs with 1 or more gastrointestinal masses composed primarily of eosinophilic infiltrates for which no underlying cause was found.
Methods: Retrospective case series.
Results: Rottweilers and purebred, large breed dogs predominated. Dogs were middle-aged and typically had chronic signs of upper or lower gastrointestinal disease. Decreased appetite, vomiting, and evidence of gastrointestinal hemorrhage were present in the majority of cases. An abdominal or rectal mass was frequently noted on physical examination. Common laboratory abnormalities included peripheral eosinophilia, mature neutrophilia, hypoproteinemia, and hypocholesterolemia. The masses were histologically composed of moderate to severe eosinophilic infiltrates, which were often transmural and accompanied by fibrosis. All dogs treated with surgery alone died of complications of their disease. Treatment with corticosteroids and ivermectin improved clinical signs, caused resolution of eosinophilic infiltrates, and prolonged survival in most dogs treated medically.
Conclusions and Clinical Importance: These findings suggest that the prognosis for dogs with IEGM may be good when recognized and managed appropriately. When surgery is performed, medical treatment should also be added.  相似文献   
43.
Background: Peritoneal D-Dimer concentration can be determined to assess peritoneal fibrinolysis activity in horses with gastrointestinal disorders. However, blood contamination of peritoneal fluid may occur during collection and could alter peritoneal D-Dimer concentration.
Hypothesis/Objectives: Blood contamination in peritoneal fluid does not affect interpretation of peritoneal D-Dimer concentration in horses with colic.
Animals: Thirty-four horses with colic and 4 healthy horses.
Methods: Peritoneal fluid and blood samples were simultaneously collected upon admission. Then, peritoneal fluid was serially contaminated with the horse's own blood; final contaminations corresponded to 1, 5, 10, and 20% of blood in peritoneal fluid. D-Dimer concentration was determined in blood, peritoneal fluid, and contaminated peritoneal fluid samples. Data were analyzed using a longitudinal linear model and a generalized estimating equations analysis to assess the quantitative and qualitative variations of the effect of blood contamination on peritoneal D-Dimer concentration.
Results: Peritoneal D-Dimer concentration was only quantitatively affected when peritoneal fluid was contaminated at 20% of blood. However, when using increasing cut-off values of peritoneal D-Dimer concentration (100, 2,000, 8,000, and 16,000 ng/mL), this effect disappeared at the highest cut-off values (8,000 and 16,000 ng/mL). When peritoneal fluid contamination was grouped as "minimally contaminated" (≤1% of blood) and "highly contaminated" (≥5% of blood), no significant differences on D-Dimer concentration between both groups at each cut-off value were observed.
Conclusions and Clinical Importance: Although quantitative results of peritoneal D-Dimer concentration could be affected by high levels of blood contamination (≥20%), interpretation of increased peritoneal fibrinolytic activity was not significantly affected.  相似文献   
44.
本试验旨在研究日粮碳水化合物/蛋白质水平对240日龄不同品种猪肌内脂肪(IMF)含量和胃肠道重量、长度及消化酶活性的影响,并探讨IMF含量与胃肠道重量、长度及消化酶活性的关系.试验采用2×2因子试验没计,即杜洛克×长白×大约克三元杂交猪(DLY)和太湖猪2个品种,每个品种分别饲喂高碳水化合物/低蛋白(HC/LP)和低碳水化合物/高蛋白(LC/HP)2种日粮.选用150日龄的DLY猪和太湖猪各12头,按体重相近、性别一致的原则共分为4个试验组,每个试验组6个重复,每个重复1头猪.饲养90 d后屠宰取样.结果表明:与LC/HP日粮相比,HC/LP日粮极显著提高了DLY猪的IMF含量(IMF为5.83%)(P<0.01),对太湖猪有提高的趋势(P>0.05),但2种日粮对2品种猪眼肌面积和背膘厚没有显著影响(P>0.05);HC/LP日粮显著(P<0.05)或极显著(P<0.01)降低了2品种猪的胰重和胰指数;无论在何种日粮下,太湖猪的胃、胰、小肠指数都极显著高于DLY猪(P<0.01);HC/LP日粮降低了2品种猪的消化酶活性,但对DLY猪的胰淀粉酶单位活性有所升高(P>0.05),其中对太湖猪的胃蛋白酶和胰脂肪酶活性的影响达到极显著水平(P<0.01).在LC/HP日粮下,太湖猪胰脂肪酶活性极显著高于DLY猪(P<0.01);在HC/LP日粮下,DLY猪的胰淀粉酶活性显著高于太湖猪(P<0.05).因此,HC/LP日粮在对2品种猪眼肌面积和背膘厚影响较小的情况下,可大幅度提高240日龄DLY猪的IMF含量,而大幅度降低了2品种猪的胰重和太湖猪的胃蛋白酶和胰脂肪酶活性,对2品种猪的胃、肝和小肠的重量或长度影响不大.  相似文献   
45.
Gastrointestinal nematodes are becoming increasingly resistant to the commercial products used to control them. The cost of routine vermifuge applications on herds and the problem of residues in animal products and the environment have prompted research on the anthelmintic activity of plant extracts. This work examines the anthelmintic action of neem and the homeopathic product Fator Vermes in sheep kept in a pasture for 18 months. Forty sheep of the Morada Nova breed were divided into four treatments and the control, according to the EPG. During the experiment, each animal received 100 g/day of shredded corn and did not receive protein supplementation. In treatment 1 (control), the animals received only shredded corn. Treatment 2 received 1.6 g/(animal day) of the homeopathic product mixed with the shredded corn, and treatments 3, 4 and 5 received, respectively, 12.5, 25.0 and 37.5 g/(animal day) of dried Azadirachta indica leaves mixed with the shredded corn. The neem was administered for alternating 15-day periods and the homeopathic product daily for 18 months. There were 39 fortnightly fecal collections made to count the EPG, and fecal cultures were performed monthly. The following genera, in percentage, were identified: Haemonchus: 65.58+/-3.27, Trichostrongylus: 15.92+/-7.38 and Oesophagostomum: 18.50+/-6.22. The treatments evaluated were not effective in controlling gastrointestinal nematodes (P>0.05), whose mean log(10) counts (EPG +1) and standard errors for treatments 1-5 were respectively 3.55+/-0.28; 3.48+/-0.31; 3.90+/-0.29; 2.78+/-0.29 and 3.48+/-0.30. A significant effect (P<0.0001) was observed of the periods of the year when the 39 collections occurred. Because of the diet deficient in raw protein, the sheep had higher average EPG counts, for all the treatments, at the end of the dry season, and the opposite occurred in the middle of the rainy season.  相似文献   
46.
采用传统的细菌培养方法,对大菱鲆(Scophthalmus maximus)育苗生产过程中不同发育时期仔稚鱼的消化道、投喂饵料和养殖水源中的可培养细菌进行了菌群结构分析和优势菌株的16S rDNA同源性比较,揭示其形成过程和演替规律。结果显示,在大菱鲆仔稚鱼5?36日龄的不同发育时期,消化道中的细菌数量呈现了先升高后降低的变化趋势,在17?26日龄期间,仔稚鱼消化道可培养细菌数量级在105?106 CFU/g以上,并且与其他时期存在极显著差异(P<0.01)。弧菌总量呈现先升高后稳定的变化趋势,17日龄之前与之后存在显著差异(P<0.05)。至投喂颗粒饵料期,细菌总量和弧菌总量均稳定在104 CFU/g数量级,弧菌成为大菱鲆仔稚鱼消化道中的优势菌种。本研究发现,大菱鲆仔稚鱼发育早期消化道中的优势菌群变化明显,并且生物饵料中的细菌对消化道中的菌群结构影响较大,其中的Vibrio ichthyoenteri最终成为仔稚鱼消化道中的优势菌种。  相似文献   
47.
景怡  胡天惠 《安徽农业科学》2011,39(30):18521-18522,18525
[目的]考察"青皮散"乳液对胃轻瘫模型动物胃肠动力的影响,探讨其作用机制。[方法]建立胃肠动力障碍模型动物,测定灌服"青皮散"乳液后模型小鼠胃内容物残留率、小肠中阿拉伯胶活性炭粉混合物的推进距离;测定灌服"青皮散"乳液后模型大鼠血浆及胃、肠组织匀浆中胃动素(MTL)水平及其在胃窦和空肠中MTL的分布变化。[结果]"青皮散"乳液能明显加快胃肠动力障碍模型动物胃排空速率,降低胃内容物残留率,增加小肠推进百分比,显著升高胃肠动力障碍模型动物血浆及胃、肠组织匀浆中MTL水平,明显增加胃窦及空肠MTL阳性物质的表达。[结论]"青皮散"乳液促实验动物胃肠运动作用与血浆、胃、肠组织匀浆MTL水平的增加及胃肠道MTL细胞分布变化有关。  相似文献   
48.
The aim of this paper is to review the most relevant findings obtained over the last four years on the physiology, microbiology and immunology of the gastrointestinal tract of pigs as influenced by weaning and nutrition in the post-weaning period through the action of feed components or alternative substances to in-feed antibiotics. In recent years, some light has been shed on the physiology of the stomach, including motility, gastric emptying and acid secretion. This organ is important in the control of pathogen entry into the intestines. Recent studies on basic intestinal physiology around weaning have been scarce. Most investigations have been devoted to nutritional approaches on the effects of diet components (e.g. protein, fibre, etc.) and alternative substances (e.g. organic acids, zinc, prebiotics, probiotics, other substances of animal or plant origins) on pig performance and various aspects of gastrointestinal tract physiology, microbiology and immunology. Among these, beneficial effects of some organic acids have been confirmed. Additional data with zinc sources include possible mechanisms of protection. Overall it appears that manipulating carbohydrate (prebiotic) composition of the weaning diet may be the most promising way to improve gut health in weaned piglets. In that respect, consistent results have been obtained with lactose supplementation, and interactions with other feed constituents have been studied. Significant positive results have also been produced with probiotics (bacteria, yeasts) fed to the piglets or to the sows. The major parts of the responses appear to be mediated through changes in gastrointestinal microbiology, including enhanced numbers of favourable bacteria (lactobacilli, bifidobacteria) and/or decreased numbers of potentially pathogenic bacteria (Escherichia coli, Clostridia, etc.) together with more favourable profiles of fermentation products along the intestines. In contrast, measurable effects of these dietary factors on intestinal physiology and mucosal immunology have been limited or difficult to interpret in many cases. Finally, investigations have been conducted with varying diet composition (other than carbohydrates: protein source or level, amino acids, etc) or supplementing with different substances of animal or plant origin. However, positive effects on the gut have often been more variable and sometimes inconsistent.  相似文献   
49.
An experiment was designed to study the effect of corn physical structure and different types of dietary fibre on pig gut microbiota during growing. Ninety-six animals (15 ± 2.2 kg) were assigned to four different diets: a control diet (CT), a diet with coarse ground corn (CC), and other two with 8% of sugar beet pulp (BP) or 10% of wheat bran (WB). Thirty-two animals (8 per diet) were sacrificed on days 7, 21 and 42 to measure microbial activity in digesta. Other 8 pigs were sacrificed on day 0 before receiving the diets. Enterobacteria and lactobacilli population in colon were quantified by qPCR. With all diets enterobacteria diminished with time and were lower than lactobacilli. Expressed as lactobacilli:enterobacteria ratio we found differences between diets at day 7 and 21 that had disappeared at day 42. Purine bases (PB) concentration indicated an adaptation of the microbiota with time which was reflected in an increasing content in the caecum and a decreasing content in the colon. Time of adaptation of microbiota was also shown by xylanase and cellulase activities that were not detected until day 7 and 42, respectively. Results obtained shows that pig gut microbiota need a relative long time to adapt after a change of diet that could last up to 6 weeks. We were not able to detect a clear effect of dietary fibre content on this process.  相似文献   
50.
The purpose of this study was to investigate the potential benefits of yeast cell wall (YCW) on the gastrointestinal development of weaned calves. Twenty healthy Holstein male calves (BW = 92 ± 8.29 kg and 60 ± 5 d of age) were randomly allocated into 2 groups: CON with no YCW, and YCW (accounted for 0.16% of the basal diet). The dietary concentrate-to-roughage ratio was 40:60. All the calves were fed regularly twice a day at 09:00 and 16:00 and had free access to water. The experiment lasted for 60 d. The results showed that calves fed YCW showed higher (P < 0.05) length, width, and surface area of papillae in the ventral sac of the rumen as compared to CON. For the dorsal sac of the rumen, the muscularis thickness was thicker (P < 0.05) in the YCW group when compared with CON group. The villus height of YCW calves was higher (P < 0.05) than that of CON in the ileum. Calves supplemented with YCW also showed a higher (P < 0.05) villus height-to-crypt depth ratio in the ileum. The YCW calves exhibited a greater (P < 0.05) thickness of the wall in the duodenum and jejunum. Calves supplemented with YCW improved (P < 0.05) the claudin 1 mRNA expression in the ileum and occludin mRNA expression in the jejunum and ileum. The YCW increased (P < 0.05) the contents of secretory immunoglobulin A in the jejunum and ileum of calves. In conclusion, dietary supplementation with YCW could improve the gastrointestinal development of weaned calves.  相似文献   
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