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1.
在光镜和电镜水平下对太湖鹅松果体组织结构和细胞结构进行研究,结果表明,鹅松果体主要由松查体细胞组成,其间夹有少数胶质细胞,松果体细胞偶尔排列为滤泡状,松果体细胞具有突起,胞核椭圆形,胞核椭圆形,圆形,线粒体常在胞附近集聚,粗面内质网丰富,高尔基体发达,胞质中有散在的游离核蛋白体,脂滴和溶酶体,胞突中微管方向与胞突平行,胞体中方向不一,质细胞的胞核不规则,胞体和胞突中含有微丝。  相似文献   

2.
成年母鸡松果腺组织结构的研究   总被引:1,自引:0,他引:1  
用透射与扫描电镜和荧光显微镜对25只成年母鸡的松果腺进行了系统观察。松果腺主要由松果体细胞组成,其间夹杂有少量胶质细胞。松果体细胞的核呈圆形或椭圆形,而胶质细胞的核多呈不规则形。松果体细胞具有突起,线粒体丰富,高尔基复合体发达,胞质中散布有核糖体,并见有粗面和滑面内质网、微管、溶酶体、脂滴以及少量致密核芯小体和板层小体。胶质细胞的结构特征为胞质中含有微丝。毛细血管内皮不含窗孔。本研究结果表明,鸡松果体细胞具有内分泌细胞的结构特征,因而认为鸡的松果腺是一个内分泌腺。  相似文献   

3.
莱芜黑山羊松果体超微结构及5-羟色胺分布的季节性变化   总被引:1,自引:0,他引:1  
应用5-羟色胺(5-HT)免疫组织化学方法和电镜技术,对莱芜黑山羊4个季节的松果体进行了研究.结果显示:(1)松果体内有大量5-HT阳性的松果体细胞及纤维;(2)松果体5-HT免疫阳性细胞面积以冬季最大,且与其他3个季节差异极显著(P<0.01);夏季最小;春秋季之间无明显差异(P>0.05).4个季节5-HT阳性细胞的光密度差异不大(P>0.05).松果体中5-HT阳性面积占总面积的比值.春、秋季相差不大(P>0.05),夏、冬季差异极显著(P<0.01);(3)松果体细胞有明细胞和暗细胞之分,2种细胞超微结构明显不同.明细胞胞核较大,常染色质多,粗面内质网(RER)、游离核糖体丰富,高尔基复合体的扁平囊泡层数较多,线粒体嵴发达,糖原较少;暗细胞的异染色质多,RER和游离核糖体较少,高尔基复合体的扁平囊泡层教少,线粒体嵴缺乏,糖原较丰富.结果提示,明细胞功能较暗细胞活跃;(4)不同季节松果体内明、暗细胞的数量不同,冬季为明细胞,夏季为暗细胞,春、秋2季2种细胞皆有,表明季节是影响松果体结构和功能活动的重要因素.  相似文献   

4.
本试验旨在探讨松果体细胞与季节性繁殖的关系,为进一步揭示山羊季节性繁殖的内分泌机理提供参考。通过透射电镜观察济宁青山羊松果体细胞超微结构的季节性变化。结果表明:①松果体细胞可分为明细胞和暗细胞,在明细胞内滑面内质网(SER)的含量较粗面内质网(RER)丰富,而暗细胞内RER含量较丰富。另外明细胞内高尔基复合体和线粒体都较暗细胞内的复杂,但暗细胞内有较多的糖元颗粒。②夏季松果体细胞以暗细胞为主,明细胞较少,而春季明、暗细胞都较多。济宁青山羊松果体细胞的功能活动呈现季节性变化。  相似文献   

5.
采用免疫组化SABC法,对冬季莱芜黑山羊松果体中含5-羟色胺细胞及纤维进行研究。结果显示:①松果体内存在大量5-羟色胺阳性的松果体细胞,细胞轮廓较清晰。②松果体的蒂部、被膜及内部含有丰富的5-羟色胺纤维,且呈现出不同的形态和免疫反应强度。  相似文献   

6.
采用免疫组化SABC法,对冬季莱芜黑山羊松果体中含5羟色胺细胞及纤维进行研究。结果显示:①松果体内存在大量5羟色胺阳性的松果体细胞,细胞轮廓较清晰。②松果体的蒂部、被膜及内部含有丰富的5羟色胺纤维,且呈现出不同的形态和免疫反应强度。  相似文献   

7.
兔脑炎原虫的超微形态与发育   总被引:1,自引:0,他引:1  
用电镜连续7代动态地观察了培养细胞中兔脑炎原虫的超微结构与发育状态。脑炎原虫含有细胞核,但无线粒体、内质网和高尔基复合体等细胞器,其表面有几根极丝。脑炎原虫在培养细胞中除二分裂增殖外,还有裂体增殖和配体增殖。由于脑炎原虫有3种增殖方式,故在光学显微镜下呈多形态结构。  相似文献   

8.
银狐、蓝狐及貉松果体的形态及组织结构初步研究   总被引:1,自引:1,他引:0  
银狐、蓝狐及貉松果体的形态位置相近。3 种动物松果体的不同之处是:蓝狐松果体体积最大,细胞密度最小,毛细血管最丰富,银狐松果体毛细血管比貉多一些,细胞密度稍小,银狐松果体细胞核直径平均为5-2 μm ,蓝狐平均为4-6 μm ,貉平均为4-3 μm 。  相似文献   

9.
休产期和产蛋期太湖鹅甲状腺的组织细胞结构比较   总被引:5,自引:0,他引:5  
在光镜和电镜水平对太湖鹅甲状腺休产期和产蛋期的组织和细胞结构作对比观察。鹅甲状腺组织是滤泡状结构 ,滤泡由单层上皮细胞构成。产蛋鹅甲状腺滤泡腔内富含胶质。休产期鹅甲状腺滤泡腔内胶质较少 ,空泡化程度高 ,呈现功能旺盛状态 ,上皮细胞顶端具有许多微绒毛 ,以摄取滤泡腔内的胶体 ;胞质内线粒体、胶质滴、溶酶体数量较多 ,内质网丰富 ,高尔基体发达。  相似文献   

10.
选用48头成年母牦牛,采用光镜和电镜技术对发情周期中不同时期黄体的组织结构进行了观察。结果表明,牦牛黄体主要由2种细胞组成,即颗粒黄体细胞(granulasa lutein cell,GLC)和膜黄体细胞(theca lutein cell,TLC),其特征性变化主要表现在GLC和纤维的分布。成熟黄体中GLC及其胞核的平均直径分别为36.6μm和15.2μm,而TLC则分别为14.4μm和10.9μm。黄体细胞胞质中线粒体的比例随黄体的成熟而增高;脂滴在Ⅰ期黄体时较多,Ⅱ期时减少,Ⅲ期时显著增多,后又减少;滑面内质网也随黄体的成熟而增加,并随黄体的退化发生膨胀。黄体组织中有同心圆状或同心轮状的粗面内质网膜系统。黄体细胞间主要是缝隙连接,偶见中间连接。黄体组织中存在窗孔型毛细血管.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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