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1.
载人飞船在上升和返回时，航天员会遇到较为强大的胸一背向超重（＋Gx）压力的作用。特别是飞船在主动段大气层外弹道式应急返回时，过载峰值可高达15G甚至20G以上。以往的研究表明，＋Gx作用对人体肺脏和呼吸功能的影响最为突出，除可引起呼吸困难、胸痛等症状外，还可导致咯血、气胸等病理性损伤，但有关＋Gx过载作用后胸腔脏器，特别是有关心脏所呈现的损伤性病理变化和机制目前未见报道。吴斌等研究了＋Gx作用对大鼠膈肌收缩性能的影响及其机理，从而揭示了＋Gx导致大鼠膈肌疲劳的原因可能与＋Gx作用下缺血缺氧引起的膈肌能量代谢和超微结构的改变有关。 相似文献
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电针麻醉对绵羊生理生化指标的影响 总被引：1，自引：0，他引：1
针刺绵羊百会、三台二穴，研究电针麻醉对心率、呼吸频率、体温、血糖、血清谷转氨酶（ＧＯＴ）、谷丙转氨酶（ＧＰＴ）等生理生化指标的影响。结果表明，电针麻醉使心率略有下降，体温、呼吸频率有所上升；电针麻醉过程中血糖含量上升；ＧＯＴ、ＧＰＴ含量变化不显著。 相似文献
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对人工感染日本血吸虫尾蚴45d的家兔作主动脉灌注冲虫，获得的成虫经Earle’s液洗涤，加入细胞培养板内，用含10％牛血清的RPMI-1640培养液于37C、5％CO2培养箱中培养，将30mg／L的苏云金杆菌BtYBT-1532和HD-1毒素蛋白分别加入各孔中，取培养1、2、4、8、24、48h的虫体，制作超薄切片进行透射电镜观察。结果发现：HD-1不引起血吸虫体壁超微结构的变化。YBT-1532毒素则引发血吸虫成虫表皮的各种变化，包括基质空泡化，褶嵴肿胀粘连，基膜和环肌肿胀，杆状分泌小体和指环体减少，感觉结构坏死，环肌溶解，体壁细胞胞质内细胞器溶解坏死，纵肌肿胀，褶嵴破渍；雌虫肠壁基质脂滴增多，出现坏死区域。上述超微结构的改变均随毒素感作时间的延续而渐进增重。 相似文献
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牛磺酸对酒精性脂肪肝大鼠脂肪代谢的影响 总被引：2，自引：0，他引：2
采用白酒灌胃及饲喂高脂饲料的方法建立大鼠酒精性脂肪肝病模型，探讨牛磺酸对酒精脂肪肝病大鼠脂肪代谢的影响。将40只Wister大鼠随机分为对照组（10只）、模型组（10只）、预防组（10只）和治疗组（10只），试验周期共为16周。检测牛磺酸干预后大鼠血清中的总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）、甘油三酯（TG）、甲状腺激素（T3、T4）的含量，制作大鼠肝组织切片，观察病理学变化，从而研究牛磺酸的药理学效应。结果表明，牛磺酸可以有效降低大鼠血清中TC、LDL-C、TG、T4含量，提高大鼠血清中HDL-C、T3含量；牛磺酸能够减轻肝的病理损伤程度，表现为牛磺酸干预后大鼠肝细胞脂肪变性数量明显减少，脂肪空泡变性程度明显减轻。 相似文献
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显示心脏传导系的标本制作 总被引：1，自引：0，他引：1
观察心脏传导系形态的方法很多，可归纳为两大类：一类是肉眼直接观察（借助于解剖显微镜），或辅以染色以显示心传导法，又称大体解剖法；另一类是组织切片染色法，又称显微解剖法。本主要介绍肉眼观察和辅以染色以显示心脏传导系的方法。我们已对3例羊、3例猪、5例牛和5例狗的心脏进行了对比试验观察。结果，肉眼直接观察法主要适用于显示动物心脏传导系中窦房结、房室结和房室束及左右束技的部分分枝，通过分离修整，使其充分显示出来。辅以染色显示心传导法主要适用于显示浦金野氏纤维清晰可见；另一种是在新鲜心脏标本的心内膜下涂以（3-5%）复方碘溶液，染色后使浦金野氏纤维更为明显。在实践中，发现不同的动物心脏和相同动物不同个体的心脏的浦金野氏纤维更为明显。在实践中，发现不同的动物心脏和相同动物不同个体的心脏的浦金野氏纤维不一样。有的很明显，在室中隔心内膜下可用肉眼看到呈网状；有的不很明显，必须辅以染色才能显示出来。 相似文献
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日粮中添加L—NAME对肉鸡腹水综合征发生的影响及其机理 总被引：6，自引：1，他引：5
应用低温环境和日粮中添加三碘甲腺原氨酸（3，3，5－triiodothyronine,T3)诱发肉鸡腹水综合征，同时通过日粮添加一氧化氮合酶抑制剂L－NAME，研究了抑制NO的合成对肉鸡肺动脉压及肉鸡腹水综合征发生的影响。180羽AA肉鸡随机等分为对照组（C）、试验组（A、B），参试鸡14日前按常规条件饲养。14日龄后C组鸡按常规条件饲养，A、B组鸡舍温按每日1－2℃逐步降至12℃，同时日粮中添加T3 1．5mg/kg以诱发腹水综合征。另外，B组肉鸡从14日龄起在日粮中添加100mg/kgL－NAME至试验结束。分别于3、4、5、6周龄测定各组肉鸡肺动脉平均压（mean pulmonary arterial pressure,mPAP)、红细胞压积、右心全心比、血浆一氧化氮（NO）和内皮素（endothelin-1,ET-1)水平并记录腹水综合征发病率。结果显示：低温添加T3处理后，A、B组肉鸡腹水综合征发病率增加，但B组高于A组；A、B组肉鸡mPAP从5周龄起高于C组（P＜0．05）；A、B组右心全心比的升高分别在6、5周龄时出现，B组右心全心比的升高比A组提前1周；B组 肉鸡血浆NO水平低于A组，差异不显著；A、B组肉鸡血浆ET－1水平高于C组（P＜0．05）；在6周龄时，A组肉鸡心率明显降低，B组肉鸡心率明显升高。随着肺动脉高压和右心肥大的出现，心率的升高可能促进了右心衰竭和肉鸡腹水综合征的发生。上述结果提示，抑制NO的合成可能促进了肉鸡肺动脉高压，右心肥大的形成和肉鸡腹水综合征的发生。 相似文献
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【目的】探究马兜铃酸Ⅰ（aristolochic acid Ⅰ，AA-Ⅰ）对大鼠五脏（心脏、肝脏、脾脏、肺脏和肾脏）的毒性及功能影响，为今后马兜铃属类中药临床用药提供参考。【方法】将SD大鼠随机分为AA-Ⅰ给药组和空白对照组，给药组按20 mg/kg灌服AA-Ⅰ，连续7 d。于给药后0.25、0.5、1、2、24 h及停药后15 d，采集大鼠五脏组织。利用HPLC法检测各个时间点五脏组织中的AA-Ⅰ及马兜铃内酰胺Ⅰ（aristolactams-Ⅰ，AL-Ⅰ）含量，并检测大鼠五脏主要生理功能及病理组织学变化。【结果】给药后0.25 h，AA-Ⅰ主要分布于心脏、肝脏、脾脏和肺脏，同时在肝脏和脾脏中检测到AL-Ⅰ；给药后0.5 h，AA-Ⅰ主要分布于心脏、肝脏、脾脏、肺脏和肾脏，除心脏外，其余四脏中AA-Ⅰ含量均达到高峰值，且在肝脏、肺脏、肾脏中检测到AL-Ⅰ；给药后1 h，AA-Ⅰ主要分布于肝脏和肺脏，且在肝脏中检测到AL-Ⅰ；给药后2 h，AA-Ⅰ主要分布于心脏、肝脏、肺脏和肾脏，且在肾脏中检测到AL-Ⅰ；给药后24 h，AA-Ⅰ主要分布于心脏和肝脏，且在肝脏中检测到AL-Ⅰ；停药后15 d，五脏中均未检测到AA-Ⅰ及AL-Ⅰ。功能检测结果显示，大鼠灌服AA-Ⅰ可引起五脏发生氧化应激损伤。【结论】连续7 d给大鼠灌服20 mg/kg AA-Ⅰ，在五脏中均可检测到不同含量的AA-Ⅰ，且在肝脏、肾脏、肺脏及脾脏中检测到AL-Ⅰ。AA-Ⅰ可对五脏造成不同程度的损伤，其损伤与氧化应激有关。 相似文献
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实验旨在探究附植期热应激对小鼠胚胎发育和生殖嵴损伤的影响。将108只体重为（30±3）g的见栓0.5d(0.5dpc)孕鼠随机分配为对照组（24±1℃室温饲养）、38℃热应激组和40℃热应激组；热应激组于4.5dpc分别以38℃和40℃热应激2h/d，连续7d。记录孕鼠每日体重，于13.5dpc取小鼠胚胎，同时记录胚胎数量、胚胎重量和死亡胚胎数量，统计分析胚胎雌雄比率、含死亡胚胎的子宫比率、胚胎分布异常的子宫占比、胚胎子宫内异常分布比率；采用组织切片及透射电子显微镜观察生殖嵴组织细胞结构的变化。结果显示：与对照组相比，38℃和40℃热应激可降低孕鼠4.5～10.5 dpc和0.5～13.5 dpc体重增长率以及胚胎重量（P<0.05），同时增加胚胎子宫内分布异常比率（P<0.01）;40℃热应激可降低附植胚胎数量及增加胚胎分布异常的子宫占比（P<0.05）;38℃和40℃热应激导致生殖嵴组织细胞间隙明显增大，细胞连接方式多为桥粒连接，粗面内质网及部分线粒体肿胀，溶酶体与自噬泡增多。上述研究结果表明，附植期孕鼠遭受热应激导致胚胎发育迟缓及生殖嵴组织细胞超微结构损伤。 相似文献
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本文应用烟酰胺腺嘌呤二核苷酸四唑氧化还原酶（NADH-TR）组化染色，将大鼠与家兔小腿胫前肌与腓肠肌的肌纤维型分成染色最深的快缩氧化FO型、染色较深的慢缩氧化SO型、染色浅的快缩氧化酵解FOG型及染色最浅的快缩酵解FG型纤维。这与定量分析结果相吻合。并对低温液氮保存骨骼肌标本进行观察，发现小块肌组织＋生理盐水和小块肌组织＋5％二甲基亚砜（DMSO）冷冻保护剂的玻璃化冻存一起浸入液氮制成切片，都未见冰晶形成；而在用5％二甲基亚砜玻璃化冻存大块肌组织切片见有少量冰晶出现；未使用5％二甲基亚砜玻璃化冻存大块肌组织切片见有大量冰晶出现。提示小块标本超快速浸入液氮内能减少冰晶形成，保证酶组化染色切片的质量。并进一步对烟酰胺腺嘌呤二核苷酸四唑氧化还原酶组化作用机理与孵育液的科学配制进行了探讨。 相似文献
10.
人工感染鸭病毒性肠炎急性病例超微结构变化 总被引：1，自引：0，他引：1
用鸭病毒性肠炎病毒（Duck enteritis virus，DEV）CH强毒株感染成年鸭复制鸭病毒性肠炎急性病例，分别于接种后不同时间，取心、肝、肾、脾、胸腺、十二指肠、法氏囊、脑和胰组织，制作超薄切片，电镜观察。结果表明：病变最早发生于肝和肾，而鸭死亡后以免疫器官和消化器官损伤最严重；各种细胞的变化主要表现为细胞肿胀，染色质或浓缩、碎裂或溶解，线粒体溶解成空泡样结构，其他细胞器破坏；脾、胸腺、法氏囊以及小肠固有层中的淋巴细胞在感染24h后，在出现细胞坏死的同时还出现较为明显的细胞凋亡变化；而鸭死亡后淋巴细胞主要表现为黑洞核样变化，整个细胞凝聚深染，染色质固缩，细胞浆均质深染，细胞膜模糊或不完整。 相似文献
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以亚麻籽粕为原料，利用微波法进行脱毒，在单因素试验基础上进行正交试验，考察微波时间、微波功率和微波温度对亚麻籽粕微波脱毒效果的影响。用脱毒后的亚麻籽粕制作酸乳，在单因素试验基础上进行正交试验，考察发酵时间、发酵剂添加量、发酵温度对亚麻籽粕酸乳中氰化物含量的影响。结果表明：亚麻籽粕最佳脱毒工艺为微波时间60 s、微波功率640 W、微波温度70 ℃，该条件下微波脱毒后亚麻籽粕氰化物含量最低，为14.02 mg/kg；亚麻籽粕酸乳发酵最佳工艺为发酵时间9 h、发酵剂添加量1.50 g/100 mL、发酵温度41 ℃，该条件下亚麻籽粕酸乳氰化物含量最低，为8.45 mg/kg；通过酸乳发酵可以降低亚麻籽粕中氰化物含量。 相似文献
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为探讨热应激时间对小鼠心肌损伤的影响及其具体作用机制,本试验通过不同的高温(41℃)时间(0、1、2、3 h)处理小鼠,通过酶联免疫、放射免疫、组织学方法以及Western Blot,检测小鼠血清生化指标、心肌组织病理变化以及内质网应激蛋白的表达。结果表明:随着热应激时间的延长,血液中的CK、CK-MB、LDH和COR都呈上升趋势,热应激组显著高于常温对照组,且应激组间差异显著(P<0.05);光镜和电镜发现热应激小鼠心肌纤维、肌细胞等都不同程度地受损,心肌细胞凋亡、线粒体空泡化、内质网肿胀等程度加剧。Western Blot结果表明,内质网应激蛋白BiP和CHOP随着热应激时间延长表达量逐渐升高。综上,内质网应激可能参与了热应激导致的小鼠心肌损伤。 相似文献
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Itsuro KAZAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):313-316
To mimic ischemic heart disease in humans, several animal models have been created, mainly in rodents by
surgically ligating their coronary arteries. In the present study, by simply inducing burn injuries on the
bullfrog heart, we reproduced abnormal ST segment changes in the electrocardiogram (ECG), mimicking those
observed in ischemic heart disease, such as acute myocardial infarction and angina pectoris. The “currents of
injury” created by a voltage gradient between the intact and damaged areas of the myocardium, negatively
deflected the ECG vector during the diastolic phase, making the ST segment appear elevated during the systolic
phase. This frog model of heart injury would be suitable to explain the mechanisms of ST segment changes
observed in ischemic heart disease. 相似文献
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Olkowski AA Rathgeber BM Sawicki G Classen HL 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2001,48(1):1-14
The present study examines ultrastructural and molecular changes in ventricular myocardium associated with ascites cases in fast-growing broilers raised at low altitude. Extensive ultrastructural lesions were seen in the left and right ventricular myocardium of broilers with fulminant heart failure and ascites. Significant changes included lesions in the myofibril contractile apparatus, altered mitochondria, marked reduction in the myofibril component, and changes in the extracellular matrix (ECM) architecture. No lesions were observed in hearts of slow growing broilers, but mild to moderate changes (predominantly in the left ventriculum) were apparent in the hearts from some clinically normal, fast-growing broilers. SDS-PAGE profiles of washed myofibrils showed several distinctly different bands in preparations from left ventricular myocardium of ascitic birds. Western blot analysis of these samples revealed several fragments of myosin heavy chain, M-protein, and titin. Based on gelatinolytic activity, matrix metalloproteinases (MMP) in the cytosolic fraction of ventricular myocardium homogenates were identified as MMP-2. The relative activity of this enzyme appears to be considerably higher in preparations from broilers, particularly in the preparations from the left ventriculum of fast-growing broilers, in comparison to leghorns or slow growing broilers. The nature and distribution of the changes in the heart indicate that chronic cardiomyopathic process in the left ventricular myocardium occurs during the development of ascites. It is postulated that progressive deterioration of the left heart pump function caused by initial lesions in the left ventricular myocardium is a significant factor in the development of pulmonary hypertension and the pathogenesis of ascites in broilers raised at low altitude. 相似文献
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Simões K Vicentini CA Orsi AM Gregório EA Da Cruz C 《Anatomia, histologia, embryologia》2002,31(4):247-251
The histological and ultrastructural characteristics of the heart ventricle in Clarias gariepinus (African catfish) has been studied by light microscopy and transmission electron microscopy. The ventricle of the heart has a saccular shape and the myocardial wall consists of an outer thin compact myocardium and an inner well-developed spongy myocardium. The myocardial layer has small myocytes, interstitial spaces and blood vessels. The myocytes are the major constituents of the ventricular wall. They are long cells, with large nuclei, and predominantly euchromatin. The sarcoplasmic reticulum of the ventricular myocytes consists of a network of tubules and subsarcolemmal cisternae oriented mainly along the longitudinal axis of the myofibrils. In contrast to the ventricular structure of other fish species described in the literature (Greer-Walker et al., 1985; Santer, 1985; Sánchez-Quintana et al., 1995, 1996), the African catfish, a freshwater sedentary fish recently introduced in neotropical climatic environments, showed a saccular ventricle that consisted of two muscle layers, a thin compact layer with large vessels and a developed spongy layer. The ultrastructure of the ventricular myocardium of C.gariepinus is similar to that of other teleosts, inclusive that of fish with other swimming habits. 相似文献
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Maki Hanami Hidaka Anetai Saori Anetai Ryuhei Kojima Kounosuke Tokita 《Anatomia, histologia, embryologia》2023,52(2):312-317
The cardiac conduction system (CCS) is crucial for regulating heartbeats; therefore, clinicians and comedicals involved in cardiovascular medicine treatment must have a thorough understanding of the CCS structure and function. However, anatomical education of the CCS based on actual dissection and observation is uncommon, although such educational methodology promotes three-dimensional structural understanding of the observed object. Based on previous studies, we examined the CCS structure in the heart of a swine (pig, Sus scrofa domestica) which has been used in the biological, medical and anatomical curricula as science teaching materials, by using macroscopic dissection procedures. Most CCS structures in a young pig heart were successfully identified and illustrated on a macroscopic scale. The atrioventricular bundle (His bundle) was located on the lower edge of the membranous interventricular septum and was clearly distinguished from the general myocardial fibres by its colour and fibre arrangement direction. Following the atrioventricular bundle towards the atrium or ventricle with properly removing the endocardium and myocardium, the atrioventricular node or the right and left bundles appeared respectively. In contrast, the sinoatrial node was not identified. The anatomy of the CCS in young pig hearts was essentially similar to that previously reported in humans and several domestic animals. Our findings of the CCS in young pig hearts are expected to be useful for medical and anatomical education for medical and comedical students, young clinicians and comedical workers. 相似文献
19.
本研究比较了3种抗应激处理措施防控肉牛运输应激的效果。74头试验牛分4组,分别在运输前用牛支原体弱毒疫苗滴鼻、肌内注射泰乐菌素或饲料中添加泰妙菌素,并设不做任何抗应激处理的对照。分别对试验牛起运前及运达后体温、血细胞数目、血清中酶含量、牛支原体抗体水平、生长速度、发病率、死亡率及治疗成本进行比较。结果显示,起运前及运达后试验牛体温、血细胞数及牛支原体抗体水平未见明显差异;泰乐菌素肌注组试验牛发病率、死亡率显著低于对照组（P〈0．01）;对照组试验牛治疗成本为抗应激处理组治疗成本的15．9倍。结果表明,运输前进行抗应激处理有利于降低肉牛运输应激,起运前肌注泰乐菌素抗运输应激效果最好。 相似文献
20.
Xiao-hui Zhang Huai-sen Zhu Zhuang Qian Shu Tang Di Wu Nicole Kemper Joerg Hartung En-dong Bao 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(1):35-44
The protective effect of aspirin during exposure to heat stress in broiler chickens was investigated. We assayed pathological damage, expression and distribution of Hsp90 protein and hsp90 mRNA expression in chicken heart tissues after oral administration of aspirin following exposure to high temperature for varying times. Heat stress induced increases in plasma aspartate aminotransferase, creatine kinase and lactate dehydrogenase activities while causing severe heart damage, which was characterized by granular and vacuolar degeneration, nuclear shrinkage and even myocardium fragmentation in cardiac muscle fibers. After aspirin administration, myocardial cells showed fewer pathological lesions than broilers treated with heat alone. A high positive Hsp90 signal was always detected in the nuclei of myocardial cells from broilers treated with aspirin, while in myocardial cells treated with heat alone, Hsp90 in the nuclei decreased, as did that in the cytoplasm. Aspirin induced rapid and significant synthesis of Hsp90 before and at the initial phase of heat stress, and significant expression of hsp90 mRNA was stimulated throughout the experiment when compared with cells exposed to heat stress alone. Thus, specific pre-induction of Hsp90 in cardiovascular tissue was useful for resisting heat stress damage because it produced stable damage-related enzymes and fewer pathologic changes. 相似文献