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In order to detect morphological changes and activity of the apical ectodermal ridge of the chike embryo limb bud, a series of “in vitro” and “in ovo” experiments were planned. “In vitro* bioassay: ectodermal covering from stage 21 limb buds were cultured in limb bud extracts and non limb bud extracts. Tissues after culture were examined under optic and electron microscopies. “In ovo” studies: Ectodermal jakets, previously cultured, were recombinated with intact limb bud mesoderm and then grafted onto a host embryo. Limb bud extract was able to maintain the ectodermal ridge and even to regenerate flattened ridges previously cultured in non limb bud extracts. The regenerated ridge did not loose the capacity to induce the growth of distal segments of the limb. The regenerated ridge was only produced at the level of its primitive region.  相似文献   

3.
高原鼢鼠肌肉脂溶性物质抗缺氧机制的探讨   总被引:3,自引:0,他引:3  
为了探讨高原鼢鼠肌肉脂溶性物质(FSC)抗缺氧机制。分别以10%FSC、5%FSC、1%FSC、0.5%CLA(阳性对照)和蒸馏水(阴性对照)给小鼠灌胃,连续10d,在常压缺氧条件下测定小鼠存活时间,并测定小鼠心肌和骨胳肌肌红蛋白含量。结果显示,在浓度为10%时,FSC能显著提高小鼠在缺氧条件下的生存时间,并显著提高小鼠心肌和骨胳肌肌红蛋白含量。  相似文献   

4.
为了解饲喂壳聚糖后鲤鱼体内部分组织中壳聚糖的沉积情况,将210尾鲤鱼随机分为7组,即对照组和试验Ⅰ-Ⅵ组。试验Ⅰ-Ⅵ组饲料中分别添加0.50%、1.00%、1.50%、2.00%、3.00%、4.00%的壳聚糖,对照组饲喂常规饲料。正试期60 d,每隔10 d 分别从各试验组及对照组的每个重复中随机选取1尾鲤鱼,测定并比较不同处理组鲤鱼鱼鳞、鱼鳍、鱼肌肉组织中的壳聚糖沉积量。结果表明,随着养殖时间的延长和饲料中外源性壳聚糖添加量的增加,对照组和所有试验组鲤鱼的鱼鳞、鱼鳍、鱼肌肉组织中的壳聚糖沉积量均有不同程度的提高。但当饲料中外源性壳聚糖的添加量≥3.00%时,鱼鳞中壳聚糖沉积量的变化不显著(P>0.05);当添加量≥1.50%时,鱼鳍中壳聚糖沉积量的增加差异不显著(P>0.05);在相同的试验阶段,各试验组与对照组之间、各试验组之间鱼肌肉组织中壳聚糖的沉积量差异均不显著(P>0.05)。结果提示,当饲料中外源性壳聚糖的添加量达到一定程度时,鱼鳞及鱼鳍中壳聚糖的沉积量不会随着添加量的增加而显著增加,且添加不同水平的外源性壳聚糖,对鲤鱼肌肉组织中壳聚糖沉积量的影响较小。  相似文献   

5.
Arthroscopic mosaic arthroplasty in the equine third carpal bone   总被引:1,自引:0,他引:1  
OBJECTIVE--To investigate survival and function of autogenous heterotopic osteochondral grafts in a site where injuries are common. STUDY DESIGN--Three osteochondral grafts were harvested arthroscopically from the femoropatellar joint and transplanted to the third carpal bone (C(3)). Nine months later, histologic, histomorphometric, and biochemical comparisons were made between the transplanted grafts in C(3) and tissue adjacent to the recipient site, the opposing radial carpal bone (C(r)), the donor site in the femoropatellar joint, and the sham-operated contralateral C(3). ANIMALS--One mixed-breed pony and 5 Standardbred horses aged 3 to 8 years old. METHODS--Using instruments modified for equine use, four 4.5-mm-diameter osteochondral grafts were harvested arthroscopically from the distal aspect of the lateral trochlea of the right femur and inserted into the radial facet of the right third carpal bone. The fourth graft was kept as a donor-site control sample. Three months later, regular exercise was started and at 6 months, repeat arthroscopy was conducted to evaluate healing. The horses were euthanatized 9 months after transplantation, and comparisons were made between the grafts, opposing radial carpal bone, and contralateral third carpal bone. The assessment criteria included paravital staining, a modified Mankin scoring system, and biochemical analyses for collagen type, total collagen content, and sulfated glycosaminoglycan concentration. RESULTS--All horses were sound 21 days' postoperatively. At 6 months, all 18 grafts were intact but somewhat soft and opaque compared with surrounding carpal cartilage. Nine months' postoperatively, the bony portions of the grafts were well integrated with the recipient sites, but 6 grafts had histologic evidence of cartilage degeneration. From biochemical analysis of grafts, there was little or no new repair tissue invading the experimental sites, but sulfated glycosaminoglycan (proteoglycan) loss from the transplanted cartilage was marked. CONCLUSIONS--Heterotopic transfer of osteochondral grafts from the distal aspect of the lateral femoral trochlea to the third carpal bone is feasible with minor modifications of human mosaic arthroplasty instruments. The bony portion of the osteochondral grafts was quickly remodeled to provide subchondral support to the transplanted articular cartilage. The loss of proteoglycan from the transplanted cartilage indicates that the grafts might have been injured during harvesting or insertion, or, more likely, did not remodel to meet the demands of a new biomechanical environment. CLINICAL RELEVANCE--These findings suggest that arthroscopic resurfacing of focal osteoarticular defects will not be successful in the long term unless donor and recipient sites can be matched with respect to cartilage thickness, biochemical constituents, and physical properties. Mosaic arthroplasty may be indicated in selected cases in which no other options exist to create a confluent cartilage-covered surface.  相似文献   

6.
本试验旨在研究不同水平发酵棉粕替代豆粕对科宝肉鸡生长性能、屠宰性能和血清生化指标的影响。选取240只1日龄科宝肉鸡,随机分成4组,每组6个重复,每个重复10只鸡。对照组饲喂基础日粮,不添加发酵棉粕;试验组分别添加3%、6%、9%发酵棉粕代替豆粕。试验共分生长前期(1~21 d)和生长后期(21~42 d)2个阶段进行,每个阶段开始和结束时对肉鸡称重,采集血液样品,测定各阶段肉鸡生长性能、屠宰性能及血清生化指标。结果表明:①与对照组相比,试验组肉鸡1~21 d的料重比(F/G)均显著降低(P<0.05);9%发酵棉粕组肉鸡21~42 d平均日采食量(ADFI)显著降低(P<0.05);②与对照组相比,各阶段试验组肉鸡半净膛率、胸肌率、腿肌率均升高,皮下脂肪厚度显著降低(P<0.05),其中6%组42 d的胸肌率和腿肌率显著高于对照组和9%发酵棉粕组(P<0.05);试验组42日龄肉鸡屠体率升高,其中3%和6%发酵棉粕组与对照组差异显著(P<0.05);③21 d时,试验组肉鸡血清甘油三酯(TG)、葡萄糖(GLU)含量均较对照组降低,而血清总蛋白(TP)含量升高,其中6%发酵棉粕组效果最好;且42 d试验组血清钙(Ca)含量增加。综上所述,日粮中添加适量发酵棉粕可一定程度上改善科宝肉鸡生长性能,提高屠宰性能,降低血清中的TG和GLU含量,增加血清TP及Ca含量。  相似文献   

7.
The study was aimed to analyze the effect of transplanted bone marrow mesenchymal stem cells (BMSCs) on the mammary gland development and serum hormone level of Saanen dairy goat.16 healthy goats with 2 months old and similar body weight were randomly divided into control group and experimental group. The BMSCs which was amplified to the P6 generation was injected to the goat via jugular vein,and the control group was injected with the same amount of normal saline. Feeding and management of the two groups were the same. Blood samples were collected monthly,and mammary gland tissue samples were collected at 3,5 and 7 months old. Frozen sections of mammary gland tissue was prepared, the ducts and acinus numbers were observed and recorded. The results showed that after transplantation of BMSCs,at 5 and 7 months old,the ducts and acinus number of goat in experimental group were significantly higher than that of control group (P<0.05).At 5,7,8 and 9 months old,the serum E2 level of goat in experimental group was significantly higher than that of control group (P<0.05);At 5 to 9 months old,the serum P level in experimental group was significantly higher than that of control group (P<0.05).At 7 to 9 months old,the serum PRL and INS levels in experimental group were significantly higher than that of the control group (P<0.05);At 8 and 9 months old,the serum levels of GnRH level in experimental group was significantly higher than that of the control group (P<0.05).The serum LEP,CRH and ACTH levels were higher than that of the control group at the whole test process,but the difference was not significant (P>0.05).In conclusion, injection of BMSCs could increase the duct and acinus number of dairy goat mammary,improve the hormone level in serum,and promote mammary gland development.  相似文献   

8.
试验旨在研究移植骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)对萨能奶山羊乳腺发育的影响。选取体重接近的2月龄健康萨能奶山羊16只,随机分为对照组和试验组。将扩增至P6代的BMSCs经颈静脉注射至奶山羊体内,对照组注射等量生理盐水,两组间饲养管理均相同。每月进行空腹采血,并分别在3、5和7月龄采集乳腺组织样品,制备乳腺组织冰冻切片,观察记录各组乳腺组织导管数和腺泡数。结果显示,移植BMSCs后,5和7月龄时,试验组奶山羊的导管数、腺泡数均显著高于对照组(P<0.05)。在5、7、8、9月龄时,试验组奶山羊血清中雌激素(E2)水平显著高于对照组(P<0.05);在5~9月龄时,试验组血清中孕酮(P)水平显著高于对照组(P<0.05);在7~9月龄时,试验组血清中催乳素(PRL)和胰岛素(INS)水平均显著高于对照组(P<0.05);8、9月龄时,试验组血清中促性腺激素释放激素(GnRH)水平显著高于对照组(P<0.05);整个试验过程中试验组血清中瘦素(LEP)、促肾上腺皮质激素释放激素(CRH)和促肾上腺皮质激素(ACTH)水平均高于对照组,但差异不显著(P>0.05)。综上所述,注射BMSCs能增加奶山羊乳腺导管数和腺泡数,提高血清中激素水平,从而促进乳房发育。  相似文献   

9.
静脉注射纤维素微粒诱发肉鸡腹水综合征模型的建立   总被引:1,自引:0,他引:1  
通过翅静脉注射CM-32纤维素微粒,观察血清白蛋白(ALB)、总蛋白(TP)、血细胞压积(PCV)、血红蛋白(Hb)、腹水等方面的变化,探讨建立肉鸡腹水综合征(AS)模型的可行性。试验分为2组,试验组在20日龄时注射0.3 mL纤维素悬液,对照组注射等量生理盐水。饲养期间统计临床型AS的发病率,并分别于21、28、35、42日龄从各组随机抽样,测定右心/全心重量比值(RV/TV),检查ALB、TP、PCV、Hb、腹水液等。结果试验组AS发病率(12%)显著高于对照组(3.3%),RV/TV值显著增加。纤维素微粒阻塞在肺血管,引起明显的炎性细胞聚集和肉芽结缔组织增生。试验组血清ALB、TP在42日龄明显低于对照组,PCV在28、35日龄时显著高于对照组(P<0.05),Hb在35日龄时显著高于对照组(P<0.05),其腹水液为典型的漏出液,表明翅静脉注射CM-32纤维素微粒成功诱发了AS。  相似文献   

10.
16只3~5月龄阉割波尔公山羊随机分为4组,即对照Ⅰ组(n=3)、对照Ⅱ组(限水对照组n=3)、试验Ⅰ组(n=5)、试验Ⅱ组(限水试验组,n=5)。对照组饲喂羊精料和花生秧,试验组饲喂棉饼和稻草,同时在试验组棉饼中加入4%棉饼量的氯化钠,对照Ⅰ组和试验Ⅰ组在试验期间不限制饮水,而对照Ⅱ组和试验Ⅱ组每天限制饮水,经预试期后试验期为4个月。结果表明:(1)添加氯化钠各试验组均未发现临床型尿石症,未添加氯化钠对照Ⅰ组有1头发病,未添加氯化钠限水对照Ⅱ组有3头发病。(2)添加氯化钠不限制水组,山羊的饮水量、排尿量较未添加氯化钠组(对照组)明显增加,尿液pH值明显降低,且差异显著;而添加氯化钠限水组,山羊的排尿量、尿液pH值与限水对照组差异不显著。(3)两个试验组血清醛固酮含量较对照组明显降低,并且尿沉渣生成量明显减少。由此推测氯化钠预防棉饼诱发山羊泌尿系结石的机理是通过降低血清中的醛固酮含量,减轻醛固酮对肾脏的损害,减少了结石核心的形成和尿液中盐类结晶沉着点,在非限饮水的情况下羊还可通过增加饮水量和排尿量,使沉渣生成量减少,从而有效地防止尿石症的发生。  相似文献   

11.
Sixteen tenorrhaphies were performed at the mid-metatarsal region in eight buffalo calves under lignocaine epidural analgesia. A 2 cm long gap was created in the superficial digital flexor (SDF) tendon and immediately repaired with acellular grafts in animals of group I, 1% glutaraldehyde-preserved tendon allografts in group II. In group III, the defect was repaired with autografts. This group served as control. The contralateral limb in each animal was operated after an interval of 60 days and the animals underwent the same procedure according to the designed groups. Diclofenac sodium and Enrofloxacin was given post-operatively for 5 days. Clinical examination revealed significant increase (P < 0.05) in rectal temperature, heart and respiratory rate for 3-4 postoperative days in all the animals. Mild pain and exudation as well as early restoration of tendon gliding movements and weight-bearing were observed earlier in group I in comparison with group II. Air-tendograms revealed early organization, minimal adhesion formation and lesser thickening of tendon at the reconstructive site in the acellular group whereas in the glutaraldehyde group dense homogenous swelling with adhesions was seen along the flexors. Angiography on day 30 showed that the area of proximal and distal host tendon graft junction appeared hypervascularized, whereas the area occupied by the graft appeared relatively less vascularized. Normal vascularization was observed on day 90 in all the three groups.  相似文献   

12.
以芦竹属(Arundo)菌草绿洲3号诱导的愈伤组织为材料,进行不定芽、不定根诱导以及移栽试验。以愈伤组织为受体材料,对绿洲3号的遗传转化体系进行初步研究。结果表明,不定芽最佳分化培养基为MS+1.0 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA,不定芽诱导率为100%。不定根诱导的最适培养基为MS,不定根的诱导率为100%。在9种移栽基质中,泥炭基质中组培苗的移栽成活率最高,为100%。以绿洲3号愈伤组织预培养3 d,于农杆菌OD600值为0.1侵染10 min为宜,共培养基中添加300μmol·L~(-1)AS的条件下,共培养1 d的GUS表达率最高,为1.5%。  相似文献   

13.
Axial pattern flaps based upon the genicular branch of the saphenous artery and medial saphenous vein were developed in eight dogs. On one hind limb of each dog, the experimental flap was raised and immediately transferred to a cutaneous defect created over the lateral aspect of the lower limb distal to the stifle. A control flap was elevated and transferred on the opposite hind limb with the genicular branches of the saphenous artery and vein ligated and divided at the base of the flap. Eighty-nine per cent of the length of the flap survived in those flaps in which the genicular vessels were left intact, whereas only 54% of the flap's length survived in the control flaps. Postoperatively, all dogs were bearing weight on the limbs normally. The genicular axial pattern flap may have special clinical application in cases of cutaneous defects involving the lateral aspect of the tibia.  相似文献   

14.
本试验旨在研究饲粮中添加不同水平的红豆杉干粉对产蛋初期仙居鸡的生产性能、血清脂质代谢和抗氧化指标的影响。选取400只140日龄仙居鸡,随机分成4组,每组5个重复,每个重复20只。对照组饲喂基础饲粮,试验组在基础日粮中分别添加2%、3%和4%红豆杉干粉,预试期7 d,正试期90 d。结果表明:在试验初期(1~30 d),各试验组平均日采食量(ADFI)均低于对照组(P<0.05),4%红豆杉干粉组的产蛋率低于对照组(P<0.05);在试验中期(31~60 d),各试验组ADFI、平均蛋重与对照组无显著差异, 4%红豆杉干粉组的产蛋率高于对照组(P<0.05),4%红豆杉干粉组的料蛋比低于对照组(P<0.05);在试验后期(61~90 d),3%红豆杉干粉组的平均日采食量高于对照组(P<0.05),3%红豆杉干粉组的平均蛋重低于对照组(P<0.05),4%红豆杉干粉组的产蛋率高于对照组(P<0.05);在试验46~90 d, 2%红豆杉干粉组平均日增重较对照组降低(P<0.05);各试验组血清总抗氧化能力高于对照组(P<0.05)。综上所述,饲粮中添加不同水平红豆杉干粉可以改善仙居鸡生产性能、血清生化指标和抗氧化能力,建议产蛋期日粮中添加4%红豆杉干粉。  相似文献   

15.
This study was carried out to evaluate the healing potential of water-soluble extract of Plantago lanceolata as a topical ointment on experimental tendinitis in burros. Tendinitis was induced by injection of 2,500 U of bacterial collagenase in the superficial digital flexor tendon of both forelimbs of six male burros. Tendinitis was confirmed ultrasonographically. 48 hours after collagenase injection, two grams of 10% P lanceolata ointment was applied on one limb (treatment group) and the same amount of eucerin (the vehicle of the ointment) on the other limb (control group), every other day for 6 weeks. Ultrasonographic examination of the tendon was performed weekly during the study and mean cross-sectional area of the superficial digital flexor tendon was measured, which was found to increase significantly after injection of collagenase in both groups. From the third week, it decreased significantly in the treatment group in comparison with the control group. At the end of the study, the animals were euthanized for histopathological study of the tendons. In control group, degenerative changes in tendon could be seen, whereas significant degree of healing was observed in the treatment group. It can thus be concluded that the P lanceolata ointment was effective in promoting the healing process of the tendon.  相似文献   

16.
试验以屠宰场云岭黑山羊卵巢卵母细胞为材料,研究其玻璃化冷冻的效果。试验中选用20% EG+20% DMSO为冷冻液、冷冻环为载体,以20 s、40 s玻璃化时间冷冻GV和MⅡ期的卵母细胞。结果表明,GV期卵母细胞的形态正常率、成熟率和卵裂率都很低,且解冻成熟培养后冷冻组的成熟率和卵裂率极显著低于对照组(P<0.01)。而MⅡ期卵母细胞冷冻效果较好,毒性试验组和冷冻组形态正常率分别为91.1%和83.3%,明显高于GV期;孤雌激活后毒性组卵裂率与对照组无显著性差异(P>0.05),冷冻组的卵裂率显著低于对照组(P<0.05)。用20 s、40 s玻璃化时间冷冻的卵母细胞解冻后GV和MⅡ期各组均无显著差异。根据试验结果得出在冷冻保存中最好冷冻MⅡ期的卵母细胞,以便提高后期的卵裂率和囊胚率;卵母细胞玻璃化时间在40 s内均不影响卵母细胞的活力和发育潜力。  相似文献   

17.
The total quantitative changes of ovaries, proportion of atretic and non atretic follicles and changes of tertiary follicles in sheep after administration of increasing doses of PMSG during the anoestrous period were observed. In experimental groups the statistically significant increase of average weight, volume and dimensions of ovaries in comparison with control group were determined biometrically. The average number of tertiary follicles was greater in experimental groups but at the same time we observed a higher proportion of atretic follicles (64% of the total number in the control group; 71-77% in the experimental groups). In the group of sheep administered a dose of 1500 m.u. PMSG we determined a high proportion of luteinized follicles (as much as 21% of the total number of atretic follicles). The total number of small follicles in the so called transient phase in the comparison of experimental and control groups was not changed significantly. In the experimental group an increased incidence of preovulatory follicles and a reduction of tertiary follicle dimensions in the period of follicle cavity formation was determined.  相似文献   

18.
[目的]为了筛选饲用豌豆在肉牛饲养中的最适添加量。[方法]试验以4头安装永久性瘤胃瘘管的杂交公牛为研究对象,采用4×4拉丁方设计,试验日粮共分4组,分别为对照组:基础日粮;试验组一:精料中添加15%豌豆;试验组二:精料中添加25%豌豆;试验组三:精料中添加35%豌豆。[结果]表明试验组二和试验组三的干物质表观消化率显著高于其他两组(P〈0.05),试验组二和试验组三的酸性洗涤纤维消化率(P〈0.05)显著高于对照组;第24 h的干物质消失率对照组显著高于其他组(P〈0.05),试验组二在48 h和72 h的粗蛋白消失率显著高于对照组(P〈0.05);对照组和试验组三日粮中干物质的b值和有效降解率显著低于其他组(P〈0.05),对照组和试验组三日粮中粗蛋白的b值显著低于试验组一(P〈0.05),对照组的c值显著高于其他各组(P〈0.05),NDF和ADF的降解参数和有效降解率各组之间差异不显著。[结论]豌豆在中混合精料中的最适添加量为25%。  相似文献   

19.
Sixteen tenorrhaphies were performed at mid-metatarsal region in eight buffalo calves. A 2-cm long gap was created in the superficial digital flexor (SDF) tendon in all animals. The gap was immediately repaired with acellular grafts in animals of group I, 1% glutaraldehyde-preserved tendon allografts in group II, and in group III the defect was repaired with autografts (control group). The contralateral limb in each animal was operated after an interval of 60 days and the animals underwent the same procedure according to the designed groups. Gross observation revealed filling of host tendon-graft junction with fibrous connective tissue. Increased vascularity was seen in group I when compared with group II and III. Graft was resorbed in animals of group I and III, whereas partial absorption of graft was seen in group II. Histological observations on day 30 revealed restoration of cellularity in acellular graft and fragmentation and resorption of glutaraldehyde-preserved graft. Graft was replaced by newly formed fibrous connective tissue. Tissue reaction around polygalactin suture consisted of plasma cells, lymphocytes and macrophages. On day 90, most of the acellular graft was replaced by newly formed fibrous connective tissue. In group II the majority of graft portion remained at the site and was in a state of resorption. In the control group it was difficult to distinguish between the host tendon and the graft. Scanning electron microscopical observation showed densely packed neoformed tissue at host tendon-graft junction. Hydrolysis and invasion of connective tissue between polygalactin suture filaments, resorption of graft with cavity formation and dissolution of ground substance were observed.  相似文献   

20.
在果蝇羽化至性成熟期间补饲不同剂量的蜂王浆,研究了蜂王浆对果蝇繁殖力的影响。结果表明,补饲蜂王浆可极显著提高雌果蝇的繁殖力,其F1代成蛹数最高可比对照组高158%;而王浆对雄果蝇的繁殖力影响不明显。试验还发现,王浆对果蝇繁殖力的影响主要发生在雌性果蝇的性发育阶段。  相似文献   

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