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81.
应用链霉亲和素-生物素过氧化物酶(Streptavidinbiotincomplex,SABC)免疫组织化学技术,用胃泌素、5-羟色胺抗哺乳动物血清对重口裂腹鱼消化道内分泌细胞进行了研究。结果表明:胃泌素阳性反应细胞仅分布于前肠和中肠,以前肠前段分布最密集(32.51个细胞/mm2);5-羟色胺阳性反应细胞前、中、后肠均有分布,其密度前肠前段最高(24.25个细胞/mm2),后肠后段次之(23.56个细胞/mm2),中肠最低(15.51个细胞/mm2)。本文详细描述了各种内分泌细胞的形态特征并对其生理功能进行了初步讨论。  相似文献   
82.
Two experiments were conducted to study the effect of supplemental histamine in the diet ofearly-weaned piglets. In experiment A, 24 cross bred piglets with an average body weight of 6.10±0.40 kg,weaned at the age of 28 days, were divided into four groups, fed with basal diet of low dietary copper without(control) or with supplemental histamine at 60, 120, 180 μg kg-1 BW. During the two weeks and the thirdweek after weaning, ADG(average daily gain) of piglets were increased by 15.8% (P<0.05), 9.5% (P<0.10) by addition of 60 μg kg-1BW histamine, but decreased by addition of 180 μg kg-1BW histamine, whichalso increased the amount of E. coli in colon and the scour incidence. The secretion of gastric acid and pepsinwere improved by both dose of supplemental histamine (60, 180 pg kg-1BW) and gastric digesta pH were de-creased by both. Addition of 60 μg kg-1 BW histamine improved the activities of trypsin, amylase in duodelumdigesta. In experiment B, 12 cross bred piglets with an average body weight of 6.85±0.35 kg, weaned at theage of 28 days, were divided into two groups, fed with basal diet of high dietary copper without (control) orwith supplemental 60 μg kg-1 BW histamine. During the two weeks and the third week after weaning, ADG ofpiglets were increased by 9.8% (P<0.05), 7.0% (P<0.10). The secretion of gastric acid, activities oftrypsin and amylase in duodelum digesta, were also improved by addition of 60 μg kg-1 BW histamine. The re-sults showed that addition of histamine (60 μg kg-1 BW) in early weaned piglets could increase the secretion ofgastric acid and pepsin, reduce gastric digesta pH and scour incidence, improve activities of trypsin, amylasein duodelum digesta, and the growing performance of early weaned piglets.  相似文献   
83.
红尾副鳅消化系统结构研究   总被引:1,自引:0,他引:1  
对红尾副鳅的消化系统结构进行研究,结果表明:口咽腔顶壁有味蕾分布,粘液细胞较底壁多;胃呈"U"形,贲门部和盲囊部含有大量胃腺,而幽门与肠交接处胃腺消失;肠各段在组织结构上差异不显著;肛门粘膜下层发达。消化腺主要为肝脏和胰腺。肝细胞索明显,但无明显的肝小叶,亦无明显的中央静脉存在,但肝血窦发达;胰腺主要弥散分布于肝脏中以及胃与肠交接之处,其他还伴随着肠呈纵行分布。  相似文献   
84.
Objective A dog model was developed to study visceral pain by stimulating the ovarian ligament. Study design Prospective experimental trial. Animals Twelve 1‐year old female hound dogs weighing 25.7 ± 3.6 kg. Methods Dogs were anesthetized with sevoflurane. The right ovary was accessed via laparoscopy. A suture was placed around the ovarian ligament and exteriorized through the abdominal wall for stimulation. The noxious stimulus consisted of pulling the ovary and ovarian ligament with a force transducer. The response to noxious stimulation was determined using the anesthetic minimum alveolar concentration requirement (MAC) for sevoflurane. The ovarian MAC was compared to the standardized somatic noxious stimulation tail clamp MAC. The results are depicted as mean ± SD and corrected to sea‐level. Results The stimulus–response curve during ovarian stimulation in three dogs was hyperbolic and best represented by a three‐parameter logistic growth curve model. The curve plateaued at 7.12 ± 4.19 N. From the stimulus‐response curve, we chose 6.61 N to test the consistency and repeatability of the model in nine dogs. The ovarian stimulation MAC for sevoflurane in these dogs was 2.16 ± 0.46%. The ovarian stimulation confidence interval and limits are comparable to the results from tail stimulation MAC. The tail stimulation MACs before and after laparoscopy surgery were not different (1.86 ± 0.28% and 1.77 ± 0.38% respectively; p > 0.05) but lower when compared to the ovarian MAC (p < 0.01). The dogs recovered from anesthesia without complications. Conclusions and clinical relevance The ovarian stimulation model is an adequate and repeatable means of producing visceral stimulation to determine MAC. The model may provide a humane mechanism to study the effectiveness of analgesics for acute ovarian pain.  相似文献   
85.
A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made.  相似文献   
86.
Twenty-four gilts were inseminated pair-wise with live or dead spermatozoa from the same ejaculate. The insemination dose was 100 ml undiluted semen containing, on average, 19×109 spermatozoa. The gilts were slaughtered 1, 2, 6 and 12 h after insemination. The numbers of spermatozoa were counted in the uterus, uterotubal junction and in four equally long segments of the oviduct, called I–IV, with a haemocytometer. IV was adjacent to the uterotubal junction. The numbers of spermatozoa recovered in the uterus diminished significantly during the first 12 h after insemination. From gilts inseminated with live spermatozoa more spermatozoa were recovered in the uterotubal junction than from gilts inseminated with dead spermatozoa. Two h after insemination spermatozoa were recovered in all oviducts. Significantly more live than dead spermatozoa were recovered in Segments III and IV of the oviduct, regardless of time. In gilts inseminated with live spermatozoa the sperm count in Segment I varied significantly with time, being hiigest 2 h after insemination. At 6 and 12 h there were no distinct differences in the distribution of live spermatozoa between the various oviduct segments. The numbers of spermatozoa recovered in the oviduct were at these times apparently related to the sperm depots in the uterotubal junction.  相似文献   
87.
本文应用光学显微镜对蓝狐消化道显微结构进行了较为详细的观察,并与其它动物进行了比较。结果表明,蓝狐食管腺数量较多,苏木素深染,胃贲门腺区为邻接贲门约1.4mm左右的狭长区,其中贲门腺不含壁细胞及主细胞,由柱状细胞构成。胃底腺壁细胞含量较多。十二指肠仅在近幽门1cm的范围内具有粘膜下腺。在十二指肠部,胆管在粘膜下层形成长约1.5-2cm的壁内段。  相似文献   
88.
AIM: To investigate the protective effects of diltiazem (Dil) on liver, pancreas and small intestines in hemorrhagic-shock canines and its mechanism. METHODS: The canines were bled to a mean arterial pressure (MAP) of 5.33-6.67 kPa for 30 min to produce the model of shock. During the shock, the dogs received water-soluble calcium channel blocker Dil or normal saline. The MAP was kept at the level for 90 min, then the total blood which was bled previously was reperfused. They were observed for 240 min. RESULTS: Dil could significantly elevated MAP of the hemorrhagic-shock canines (P<0.01) and the activity of superoxide dismmutase (SOD) of pancreas tissue (P<0.01), also it could decrease content of malondialdehyde (MDA) of the liver, pancreas and small intestine tissues (P<0.01). Electron microscope data indicated that Dil-treated dogs have a normal ultrastructure in the liver, pancreas and small intestine tissues. CONCLUSION: Dil can protect the structure and function of the liver, pancreas and small intestine in hemorrhagic-shock canines.  相似文献   
89.
From 1984 until 1986, influenza isolates were obtained from 59 outbreaks of respiratory tract disease in Belgium. In 21 of the outbreaks, H3N2-influenza virus isolates, related to the human A/Port Chalmers/1/73 strain were obtained. All other isolates were H1N1-influenza virus strains. The prevalence of variants of the human H3N2-influenza virus in the Belgium swine population was determined by examining sow sera which had been collected between 1969 and 1984. The results of this serological study showed that, although a Port Chalmers-like strain was associated with outbreaks of respiratory tract disease in swine only since 1984, such strain was already present in the swine population in 1974, when a low percentage of sow sera (7%) reacted with A/Port Chalmers/1/73. Between 1975 and 1984, antibody against this strain were present in 28–61% of the sera. Furthermore, 3–6% of the sera collected between 1971 and 1980 reacted with the A/Hong Kong/1/68 strain. There were no indications that more recent human H3N2-strains (A/Texas/1/77, A/Bangkok/1/79 and A/Belgium/2/81) circulated in the Belgian swine population.  相似文献   
90.
对健康成龄本地犬20只分5组进行了39次静脉胆道造影。分别缓慢(3~4mL/min)静注胆影葡胺0.2、0.4、0.6、0.8和1.0mL/kg,于注药后20、30、40、60、120和180min分别摄取胆区X线照片。结果,注药后20min,72%的胆囊开始显影,60min时,显影率达100%;造影剂剂量以0.4~0.8mL/kg为宜,以此剂量注入后120min,胆囊显影良好者达97%,180min达100%。当剂量在0.4mL/kg体重以上时,胆管显影率为59%。饲喂缩胆剂后1~2h左右胆囊收缩到最大限度。  相似文献   
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