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141.
为明确宽叶独行菜(Lepidium latifolium L.)提取物中促胃肠动力的有效部位,在小鼠腹腔注射硫酸阿托品的方法制造胃肠动力障碍模型,测定胃内色素残留率和小肠推进比,并检测血浆胃动素(MTL)和血浆胃泌素(GAS)的含量。结果表明,正丁醇部位对小鼠胃内色素残留率的影响与模型对照组比较有显著差异,水提取部位、乙酸乙酯部位有极显著差异;水提取部位对小肠推进比的影响与模型对照组比较有显著差异,乙酸乙酯部位有极显著差异;水提取部位、正丁醇部位对小鼠MTL含量影响与模型对照组比较有显著差异,乙酸乙酯部位有极显著差异,乙酸乙酯部位对小鼠GAS含量的影响与模型对照组比较有显著差异。初步判断乙酸乙酯部位为宽叶独行菜促胃肠动力的有效部位,其作用机制还有待进一步研究。  相似文献   
142.
Sheep can be vectors for the long‐distance dispersal of weeds when seed becomes attached and retained in wool or survives the gastrointestinal tract. This study aimed to determine an appropriate quarantine period for sheep that minimized the risk of the long‐distance dispersal of the seeds of branched broomrape (Orobanche ramosa L. subsp. mutelii [F.W. Shultz] Cout.), a parasitic weed. Experiments with penned sheep found that the seeds that were placed on the soil surface adhered to the wool on the thigh and belly of the sheep, with most of the seeds attaching to the feet. Most of the seeds that were applied to the belly and thigh wool detached within 2 days, although a small proportion was present after 7 days. The seeds that were introduced to the digestive tract via drenching had a peak voidance 2 days later and no seed was detected on Day 8. It is suggested that a 7 day quarantine period for sheep would be sufficient in order to reduce the risk of the internal transport of seed to acceptable levels, but a small risk of the external transport of seed on the fleece remains.  相似文献   
143.
采用16S r DNA-PCR菌群分离鉴定的方法,对循环水养殖条件下云纹石斑鱼(Epinehelus moara)幼鱼的胃、幽门盲囊、前肠、中肠和后肠的菌群结构进行了鉴定,用产酶菌筛选培养法对产消化酶的菌株进行了分离鉴定,并测试了各菌株消化酶的活力。研究发现,云纹石斑鱼幼鱼消化道内可培养的主要菌群为假单胞菌属(Pseudomonas)、微小杆菌属(Exiguobacterium)、不动杆菌属(Acinetobacter)、寡养单胞菌属(Stenotrophomonas)和葡萄球菌属(Staphylococcus),其中产消化酶的菌株占可培养菌的55.6%。在产酶菌中,同一株菌产3种酶的有5株;产2种酶的有9株;中肠和后肠的菌株数最为丰富,胃次之,幽门盲囊和前肠菌群种类较少;产脂肪酶的菌株都集中在中肠。产消化酶的菌株主要以产蛋白酶和淀粉酶为主,且产酶量丰富,产蛋白酶活力最高达(87.732±1.134)U/m L;淀粉酶活力为(77.176±0.599)~(73.458±0.574)U/m L;产纤维素酶的菌仅一株,且酶活力较低。分析得知,消化道的菌群结构直接影响了外源性消化酶的种类与活性。本研究为工厂化循环水养殖条件下产酶有益菌的筛选提供了理论依据。  相似文献   
144.
蓝狐消化道5-羟色胺和生长抑素免疫组化定位   总被引:2,自引:0,他引:2  
采用免疫组织化学SP法.研究蓝狐消化道内5-羟色胺和生长抑素2种免疫阳性细胞的形态结构与分布密度.结果表明,消化道中这2种免疫阳性细胞形态多呈圆形、椭圆形或锥体形,主要集中分布在胃腺上皮、肠上皮及肠腺上皮细胞之间.5-HT免疫阳性细胞数量以结肠最多,直肠和空肠次之,胃底腺区、十二指肠、回肠和幽门腺区较少,食管、贲门腺区和盲肠中未见:SS免疫阳性细胞大量出现于幽门腺区,食管、责门腺区和盲肠中未见;根据其形态推测,蓝狐消化道这2种免疫阳性细胞有内、外2种分泌功能.  相似文献   
145.
Background: Surfactant alterations are described in horses after exercise, anesthesia, and prolonged transport, in horses with recurrent airway obstruction, and in neonatal foals. The effect of horse age or bronchoalveolar lavage fluid (BALF) sample characteristics on surfactant is unknown.
Objectives: To evaluate surfactant phospholipid composition and function in healthy horses, and to investigate the influence of age and BALF sample characteristics on surfactant.
Animals: Seventeen healthy horses 6–25 years of age maintained on pasture year-round.
Methods: BALF was collected by standard procedures and was assessed for recovery volume, nucleated cell count (NCC), and cytology. Cell-free BALF was separated into crude surfactant pellet (CSP) and surfactant supernatant (Supe) by ultracentrifugation. Phospholipid and protein content were determined from both fractions. CSP phospholipid composition was analyzed by high-performance liquid chromatography with an evaporative light scatter detector. Surface tension of CSP was evaluated with a pulsating bubble surfactometer. Regression analysis was used to evaluate associations between age, BALF sample characteristics, and surfactant variables.
Results: Results and conclusions were derived from 15 horses. Increasing age was associated with decreased phospholipid content in CSP but not Supe. Age did not affect protein content of CSP or Supe, or surfactant phospholipid composition or function. Age-related surfactant changes were unaffected by BALF recovery percentage, NCC, and cytological profile.
Conclusions and Clinical Importance: Older horses have decreased surfactant phospholipid content, which might be because of age-related pulmonary changes. Surfactant composition is unaffected by BALF sample characteristics at a BALF recovery percentage of at least 50%.  相似文献   
146.
缓释复合酸化剂对断奶仔猪消化道酸度及肠道功能的影响   总被引:7,自引:0,他引:7  
本试验选用28 R龄断奶、平均体质量(7.00±0.10)kg的长白猪(♂)×大白猪(♂)二元杂交仔猪64头,按单因索试验设计原则,研究在玉米一豆粕一膨化大豆型基础日粮中添加不同类型(包被未包被)复合酸化剂对断奶仔猪胃肠道酸度、生产性能、肠组织形态、消化酶活性、肠道微生物菌群及肠黏膜抗体SIgA的影响.试验设4个处理,每个处理4个重复,每个重复4头猪(公母各半),饲养试验时间为35 d.结果表明,微胶囊型缓释复合酸化剂可以极显著降低断奶仔猪胃和小肠pH(P<0.01);极显著提高空肠绒毛高度和隐窝深度的比值(P<0.01);断奶前期,显著提高小肠蔗糖酶和乳糖酶活性(P<0.05);断奶后期,极显著提高仔猪盲肠和结肠中乳酸杆菌数量,降低大肠杆菌数量(P<0.01);微胶囊型缓释复合酸化剂还有增加仔猪肠黏膜抗体SIgA分泌量的趋势(P>0.05).结果提示,在断奶仔猪日粮中添加微胶囊型缓释复合酸化剂,可以通过降低肠道pH,优化肠道微生物区系,改善肠组织形态和功能,从而提高断奶仔猪肠道的消化力和适应性,并促进仔猪生长.  相似文献   
147.
Objective   To determine a reference range for serum cobalamin concentration in healthy cats in Australia using a chemiluminescent enzyme immunoassay and to prospectively investigate the prevalence of hypocobalaminaemia in cats with non-alimentary tract disease.
Design   Prospective study measuring serum cobalamin concentrations in clinically healthy cats and cats with non-alimentary tract illness.
Procedure   Blood was collected from 50 clinically healthy cats that were owned by staff and associates of Veterinary Specialist Services or were owned animals presented to Creek Road Cat Clinic for routine vaccination. Blood was collected from 47 cats with non-alimentary tract illness presented at either clinic. Serum cobalamin concentration was determined for each group using a chemiluminescent enzyme immunoassay.
Results   A reference range for Australian cats calculated using the central 95th percentile in the 50 clinically healthy cats was 345 to 3668 pg/mL. Median serum cobalamin concentration in 47 cats with non-alimentary tract illness (1186 pg/mL; range 117–3480) was not significantly different to the median serum cobalamin of the 50 healthy cats (1213 pg/mL, range 311–3688). Using the calculated reference range one sick cat with non-alimentary tract illness had a markedly low serum cobalamin concentration.
Conclusion   Although hypocobalaminaemia is uncommon in sick cats with non-alimentary tract illness in Australia, its occurrence in this study warrants further investigation.  相似文献   
148.
A massive unilateral scrotal pyocele caused by Staphylococcus capitis in a 6‐year‐old ram is reported. Ultrasound examination of the right hemiscrotum showed an irregular hyperechoic mass in an anechoic fluid. A dense exudate was collected from the scrotum for microbiological analysis. Grossly, there was an extensive greenish purulent exudate and a completely atrophied right testis. Coagulase‐negative S. capitis was isolated in pure culture. To the authors' knowledge, this is the first report of genital infection by S. capitis in rams. This microorganism should be included in the differential diagnosis of ovine genital infections.  相似文献   
149.
150.
A 10-week-old, female, Jersey calf was referred to the University of Minnesota Veterinary Medical Center for evaluation of difficult breathing and inappetence of 18-hours duration. Cytologic examination of a transtracheal wash specimen revealed pyogranulomatous inflammation, with increased numbers of multinucleated cells. Differential diagnoses included established bacterial infection, viral infection, fungal infection, and foreign body reaction. Immunocytochemical staining was done on a direct smear of the transtracheal wash using a cocktail of 4 mouse monoclonal antibodies against 3 human respiratory syncytial virus proteins. Strong intracytoplasmic staining within mononuclear cells was observed and a diagnosis of bovine respiratory syncytial virus infection was made. Immunocytochemistry may be used as a rapid, inexpensive, adjunctive diagnostic tool for the antemortem diagnosis of bovine respiratory syncytial virus on transtracheal wash specimens.  相似文献   
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