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1.
This study concentrated on the histogenesis of bovine sympathetic ganglia, especially the development of the capsule, the interaction of sympathoblasts and supporting cells, and the ultrastructural detail of developing sympathoblasts. For this purpose 1st thoracic ganglia from 19 embryos and foetuses were collected and separated into 4 groups. The methods of study involved light and electron microscopy. From the study it was concluded that for neuronal development a functional interaction was necessary with satellite and Schwann cells, that the capsule had a role in maintaining neuronal homeostasis, and that sympathetic neurons displayed a number of morphologically distinct forms before reaching maturity. 相似文献
2.
L. De Schaepdrijver H. Lauwers P. Simoens J. P. de Geest 《Anatomia, histologia, embryologia》1990,19(3):222-235
Morphogenesis of the porcine retina was studied using light microscopy from 4 weeks of gestation until birth (18 to 310 mm crown-rump length), and compared with the adult stage (6 months). Tissue samples were examined from the posterior and peripheral parts of the retina. At 18 mm the retina consists of an inner marginal layer and an outer layer of neuroblastic cells. At 18-40 mm the latter layer is divided into an inner and an outer neuroblastic layer by the transient layer of Chievitz. Subsequently, the development of the different retinal layers begins at the inner retinal border and moves progressively outwards; it also spreads from the posterior to the peripheral part of the neural retina. Many cells of the inner neuroblastic layer are prospective ganglionic cells which migrate inwards, thus forming the ganglion cell layer and the inner plexiform layer at 90 mm. At 120 mm, primitive horizontal cells appear within the outer neuroblastic layer. Separation of this layer into the inner nuclear, outer plexiform and outer nuclear layers is first evident at 180 mm. At this stage all retinal layers are present, except the layer of the photoreceptor cells which is not widespread until at 220 mm. The inner and outer segments of the photoreceptor cells lengthen considerably during the last month of gestation. During the late fetal stage the nerve fiber layer, the inner and outer plexiform layers and the layer of rods and cones all continue to increase in thickness. Concurrently, the ganglion cell layer and the inner and outer nuclear layers have reached their maximal thickness and become thinner. After the total thickness of the neural retina amounts to approximately 180 microns at two to three weeks before birth, it then thins to approximately 160 microns in the adult stage. 相似文献
3.
为探究鹅个体发育过程中小肠绒毛形态发育情况,通过扫描电子显微镜对鹅胚胎发育过程中和成体的小肠绒毛进行形态学观察。结果表明:鹅胚胎时期,小肠绒毛经历了由山脊状黏膜褶发育为“W”形板状黏膜嵴最后变为指状绒毛的过程;出雏后,鹅小肠绒毛形态由指状变回板状。其中,鹅胚胎发育18 d后(胚胎发育的60%阶段后),小肠表面黏膜由山脊状黏膜褶变为规则的“W”形板状黏膜嵴。发育25 d后(胚胎发育的83.3%阶段后),板状黏膜嵴均变为指状绒毛。鹅胚孵出8 d后小肠指状绒毛开始变扁,17 d龄鹅的小肠指状绒毛变成板状绒毛,成体鹅一直保持板状绒毛形态。 相似文献
4.
M. Yörük R. N. Aslti N. Kurtdede Z. Agaoglu H. Altunay 《Anatomia, histologia, embryologia》1998,27(5):289-292
The purpose of this study was to determine the percentage of peripheral blood T lymphocytes and the localization of ANAE enzyme at the electron microscopic level in Van cats by using an alpha-naphtyl acetate esterase procedure. Peripheral blood samples taken from 20 Van cats were used. The percentage of ANAE positive lymphocytes was 83.0%. Neutrophilic gra-nulocytes gave a negative reaction, whereas monocytes, eosinophilic granulocytes showed a diffuse granular positivity. In the electron microscopic examination, ANAE positive reactions were seen in lysosomal granules found in lymphocytes. 相似文献
5.
无毛同类系小鼠皮肤形态及扫描电镜观察 总被引:3,自引:0,他引:3
对3种无毛同类系小鼠的皮肤形态及超微结构进行了观察。结果发现,3种无毛同类系小鼠约在12日龄开始从眶周脱毛,3~4周龄后除触须外全部脱净,并终生保持无毛状态;1月龄时,无毛小鼠内脏可视,随年龄的增长,皮肤逐渐变松、变厚,并形成特别的皱纹和褶痕,似犀牛状,指甲过度生长,呈螺旋状弯曲;BALB/c无毛小鼠无色素沉着,表型类似于豫医无毛小鼠,DBA/2、C57BL/6无毛同类系小鼠皮肤有黑色素沉着,嘴角、眶周、耳和尾部颜色较重。随年龄增长,皮肤及尾部表面出现一些类似人粉刺样的丘疹,数量逐渐增多,触须也随着年龄增长变得异常而稀疏。电镜扫描观察,脱毛前毛囊上部的毛管先变大,然后再脱毛。无毛同类系小鼠表面有较厚的一层鳞片状角化物,毛囊腔宽大,部分毛囊内含有一些能脱落到表面的角化样碎片。35日龄无毛同类系小鼠可见明显的包囊结构,4月龄包囊增多、变大。 相似文献
6.
试验探讨了铁与维生素A水平对小鼠胚胎存活的影响。选取21日龄昆明种小鼠,饲喂商品日粮2周,随后采用试验饲粮饲喂第11周时,进行交配。此后选有阴栓的小鼠随机分为1个对照组和9个处理组(采用2因素3水平完全随试验设计,铁添加水平为3.5、35、175mg/kg,维生素A水平为400、4000、20000IU/kg),每组分3个重复,每个重复6只。结果表明:妊娠3、6、18d,与对照组相比,35mg/kgFe+4000IU/kg维生素A组胚胎存活率分别提高了25.6%(P<0.05)、9.2%(P<0.05)、46.6%(P<0.05)。适量的铁和维生素A水平有利于胚胎的发育,高铁会降低胚胎的存活率。铁与维生素A对胚胎的存活率的影响存在互作效应(P<0.05)。 相似文献
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8.
不同剂量阿苯达唑治疗鼠旋毛虫病效果初探 总被引:1,自引:0,他引:1
使用不同剂量阿苯达唑对人工感染旋毛虫的小白鼠进行疗效试验,观察其不同剂量的杀虫效果.结果表明:应用阿苯达唑20 mg/(kg·d)×7治疗鼠旋毛虫病有很好的治疗效果,为阿苯达唑临床应用提供科学参考. 相似文献
9.
Enamel formation and structure were investigated in 102 developing or erupted teeth of roe, fallow and red deer. Special attention was given to the topography of the forming enamel surface, the form, arrangement and course of enamel rods, its relation to interprismatic enamel and the occurrence of Hunter-Schreger-bands in the enamel. Discussed are the significance of the enamel pattern for the identification of certain taxa and the adaptive value of Cervidean enamel structures. 相似文献
10.
The purpose of this study was to investigate the morphological changes in the epithelium of Thai swamp buffalo oviducts at the follicular and luteal phases by histological technique and scanning electron microscopy. The samples from the infundibulum, ampulla, isthmus and uterotubal junction (UTJ) of the oviduct were taken immediately after slaughter at the local abattoir. Noticeable cyclic changes were observed on the epithelial surface of the infundibulum and ampulla, but few changes were present in the isthmus and UTJ. At the follicular phase, the epithelium of infundibulum and ampulla were densely covered with ciliated cells whose cilia concealed the apical processes of the secretory cells. In contrast, the secretory cells dominated in the epithelium at the luteal phase and most of the ciliated cells were hidden by the bulbous processes of these cells. In the isthmus and UTJ at the follicular and luteal phases, the secretory cells were almost flat or gently rounded and covered with numerous microvilli at their apical surface. In conclusion, the histological and ultrastructural observation of Thai swamp oviduct epithelium revealed marked cyclic changes in the cellular differences associated with the main functions of segmental variations. 相似文献
11.
铜和维生素A及互作效应对肉仔鸡生产性能及理化指标的影响 总被引:2,自引:0,他引:2
选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每重复14只(公母各半)。采用4×2(Cu×VA)完全随机试验设计,研究了日粮添加不同水平的Cu(0,8,150,225 mg/kg)和维生素A(1 500,5 000 IU/kg),对肉仔鸡不同生长阶段(0~4周龄和5~7周龄)的生产性能及理化指标的影响。结果表明:铜的适宜添加量,前期为8 mg/kg,后期为0~8 mg/kg;全期高铜抑制了肉仔鸡生产性能、免疫功能、CuZn-SOD活性及胰岛素浓度;维生素A(5 000 IU/kg)组获得较好的生产性能、免疫功能及CuZn-SOD活性,并显著(P<0.05)抑制了血清胰岛素浓度;Cu与维生素A互作效应对前期体增重及全期料重比影响均显著(P<0.05),对后期淋巴细胞ANAE %、全期血清CuZn-SOD活性及前期血清胰岛素浓度影响均极显著(P<0.01),且二者间存在互补作用。 相似文献
12.
探讨铁与维生素A水平对小鼠子宫分泌蛋白及胚胎存活率影响。选取21日龄昆明种小鼠,随机分为9个处理组,每个处理3个重复,饲喂商品日粮2周,随后采用试验饲粮饲喂。试验采用3×3(铁、维生素A)2因子3水平有重复设计(铁添加水平为3.5、35和175 mg/kg,维生素A水平为400、4000和20000 IU/kg),饲喂第11周时,进行交配,此后选有阴栓的小鼠162只,每个处理3个重复,每个重复6只。结果表明:(1)妊娠3 d,与对照组(Fe1-VA1)相比,5组(Fe1-VA2、Fe1-VA3、Fe2-VA2、Fe2-VA3、Fe3-VA1)添加铁与维生素A对胚胎存活率影响显著(P<0.05),分别提高了20.0%、22.7%、24.7%、19.5%和7.7%。妊娠6 d,添加3.5 mg/kg Fe 4000 IU/kgVA、3.5 mg/kg Fe 20000 IU/kg VA、35 mg/kg Fe 4000 IU/kg VA和35 mg/kg Fe 20000 IU/kg VA效果较好(P<0.05)。妊娠18 d,与对照组相比,添加35 mg/kg Fe 4000 IU/kg VA组显著提高了47.4%(P<0.05);(2)铁与维生素A水平组合在对胚胎存活率、酸性磷酸酶含量、视黄醇结合蛋白含量影响显著(P<0.05)。添加35 mg/kg Fe 4000 IU/kg VA可使胚胎存活率、酸性磷酸酶含量、视黄醇结合蛋白含量和子宫总蛋白分泌含量最高;(3)175 mg/kg铁水平组降低了胚胎存活率、酸性磷酸酶、视黄醇结合蛋白和子宫总分泌蛋白含量。35 mg/kg铁水平组使胚胎存活率、酸性磷酸酶含量、视黄醇结合蛋白含量最高,提高了子宫总分泌蛋白含量;(4)4000 IU/kg维生素A组使胚胎存活率、酸性磷酸酶含量、视黄醇结合蛋白含量最大,提高了总分泌蛋白含量;(5)铁对子宫酸性磷酸酶含量影响显著(P<0.05),维生素A对视黄醇结合蛋白含量影响显著(P<0.05)。适量的铁和维生素A有利于胚胎发育;铁与维生素A水平组合对胚胎存活率、酸性磷酸酶含量、视黄醇结合蛋白含量影响存在互作效应。随着铁在3.5~35.0 mg/kg、维生素A在400~4000 IU/kg范围内增加,子宫铁蛋白、视黄醇结合蛋白增加,更好地促进胚胎存活。 相似文献
13.
F. K. Al-Bagdadi L. P. Ruhr L. F. Archbald C. W. Titkemeyer C. S. Foil 《Anatomia, histologia, embryologia》1988,17(4):349-359
Eight healthy dogs of mixed breeds with short hair coats were used in this study. The skin and the hair of a small area on the left side of the saddle region were dyed 80 times once every day with a permanent hair dye, Clairol Hair Dye Flaxen Blonde. The dyed regions were red and dry toward the last two weeks of the experiment. None of the dogs had abnormal hair shedding. Four of the dogs were restless, and their epidermis were parakeratotic and hyperkeratotic.
The cuticular cells of the hair shafts of two dogs upon examination showed deep fractures at the lower part of the hair shaft. The fractures extended through the whole thickness of the cuticular cells leading to splitting of the hair shaft. Secondary hairs showed excessive peeling of their cuticle cells causing distortion and deterioration of the cortex of the hair. Cuticular cells of large numbers of hairs lost their apical parts and some of them were deformed due to partial dissolution attributed to the intensive use of the hair dye. The intensive usage of the hair dye on the compound type of hair coat of the dog caused damage to the hair shafts and to the skin in the form of irritation, dryness and parakeratosis of the epidermis. Also, some of the dogs became restless and hyperactive during the later part of the experiment. 相似文献
The cuticular cells of the hair shafts of two dogs upon examination showed deep fractures at the lower part of the hair shaft. The fractures extended through the whole thickness of the cuticular cells leading to splitting of the hair shaft. Secondary hairs showed excessive peeling of their cuticle cells causing distortion and deterioration of the cortex of the hair. Cuticular cells of large numbers of hairs lost their apical parts and some of them were deformed due to partial dissolution attributed to the intensive use of the hair dye. The intensive usage of the hair dye on the compound type of hair coat of the dog caused damage to the hair shafts and to the skin in the form of irritation, dryness and parakeratosis of the epidermis. Also, some of the dogs became restless and hyperactive during the later part of the experiment. 相似文献
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15.
Masataka CHIHARA Saori OTSUKA Osamu ICHII Yasuhiro KON 《The Journal of reproduction and development》2013,59(6):525-535
The blood testis-barrier (BTB) is essential for maintaining homeostasis in the
seminiferous epithelium. Although many studies have reported that vitamin A (VA) is
required for the maintenance of spermatogenesis, the relationships between the BTB,
spermatogenesis and VA have not been elucidated. In this study, we analyzed BTB
assembly and spermatogenesis in the testes of mice fed the VA-deficient (VAD) diet
from the prepubertal period to adulthood. During the prepubertal period, no changes
were observed in the initiation and progression of the first spermatogenic wave in
mice fed the VAD diet. However, the numbers of preleptotene/leptotene spermatocytes
derived from the second spermatogenic wave onwards were decreased, and initial BTB
formation was also delayed, as evidenced by the decreased expression of mRNAs
encoding BTB components and VA signaling molecules. From 60 days postpartum, mice fed
the VAD diet exhibited apoptosis of germ cells, arrest of meiosis, disruption of the
BTB, and dramatically decreased testis size. Furthermore, vacuolization and
calcification were observed in the seminiferous epithelium of adult mice fed the VAD
diet. Re-initiation of spermatogenesis by VA replenishment in adult mice fed the VAD
diet rescued BTB assembly after when the second spermatogenic wave initiated from the
arrested spermatogonia reached the preleptotene/leptotene spermatocytes. These
results suggested that BTB integrity was regulated by VA metabolism with meiotic
progression and that the impermeable BTB was required for persistent spermatogenesis
rather than meiotic initiation. In conclusion, consumption of the VAD diet led to
critical defects in spermatogenesis progression and altered the dynamics of BTB
assembly. 相似文献
16.
研究光照和噪声对小鼠血液指标及肝肾功能的影响.将昆明(KM)小鼠分别放在不同光照和噪声条件下,探讨光照、噪声对KM小鼠血液常规和血清生化指标的影响.结果显示,不利的光照和噪声条件造成血常规中红细胞、血红蛋白数改变,平均红细胞血红蛋白含量、平均红细胞血红蛋白浓度发生变化;血清中ALT和AST浓度升高;ALB升高;CREA、UREA和UA降低;TG、GLU降低.可见不适宜的光照(小于150 lx或大于300 ix)和噪声(大于60 dB)环境对实验动物的肝肾功能有一定的损害,导致实验动物消化不良,出现营养不良、贫血、脱水等症状,因此实验动物环境因素与动物福利有着密切的关系. 相似文献
17.
实际生产中人们对维生素A缺乏问题很关注.近期报道维生素A和维生素E之间有拮抗作用,日粮中维生素E量对动物机体脏器中维生素A含量有很大影响.为了验证此说法,笔者进行了喂服维生素E缺乏的饲料来测定动物肝脏中维生素A含量的试验,具体过程报道如下: 相似文献
18.
28只繁殖獭兔随机均分两组,基础日粮相同,试验组自配种前3天至妊娠第7天于日粮中添加维生素A8mg/kg、维生素E100mg/kg。结果与对照组相比:试验组产活仔数提高了20.23%(P<0.05),断奶成活率提高了7.23%(P<0.05),增重提高7.11%(P<0.05)。 相似文献
19.
A new light microscopy classification of spermatogenesis in the bull and the boar was formulated to be used in conjunction with electron microscopy. It uses information available from all cell types and allows for very small portions of testicular epithelium at any orientation to be evaluated. The classification devised, being simple in outline, allows for the natural overlap of cell types. Furthermore, it emphasises the direct comparability of the morphological events occurring during spermatogenesis in the bull and the boar. 相似文献
20.
为观察猪肝动脉注射磷-32 玻璃微球(32P-GMS)对肝脏急性、亚急性反应的超微结构损伤及修复过程。用7 只健康猪经切皮肝动脉内接受由选择性导管注射直径为46~76μm 的玻璃微球。其中4 只猪注射放疗性32P-GMS;3 只猪注射31P-GMS(对照)。术后2、4、8 或16 周分批取不同部位的肝组织进行电镜常规制样及电镜观察。结果选择性导管注射32P-GMS,内放射急性期(2 周时)肝细胞均出现明显的异常和严重损伤;亚急性期(4 周时)大部分肝细胞核基本正常,胞浆细胞器仍有变化;恢复期(8 周时)大部分肝细胞已修复,肝细胞基本正常,但胶原和贮脂细胞增多。内放射16 周时,肝细胞全部修复正常。观察结果表明,当吸收剂量每次不超过200Gy 的32P-GMS经肝动脉给药时,肝细胞的损伤是短期而可逆性的。 相似文献