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1.
Six dogs were used for a radiological investigation of movement of the cervical vertebrae for comparison of range of motion, instantaneous centers of motion and patterns of flexion and extension with those determined for man. Five dogs were embalmed and one live dog was investigated under the influence of general anesthesia. All animals were adult with the exception of one of the embalmed animals. None of the animals exhibited any abnormalities of cervical vertebrae or intervertebral discs. It was demonstrated that range of motion of the dog cervical spine exceeds that of man, largely due to a greater flexion-extension range of the atlanto-occipital joint and of lateral flexion of the cranial and caudal cervical spine. Patterns of flexion and extension of the cranial and caudal cervical spine of the dog are similar to that of man with no differences in the location of centers for these movements. Other differences were primarily due to the organization of intervertebral articulations.
These relationships are discussed in regard to the significance of individual groups of cervical muscles, joint functions and influence of movement on the spinal cord.  相似文献   

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通过聚合聚链式反应从不同源性大肠杆菌的染色体DNA上扩增出大肠杆菌多药耐药基因AcrA,AcrB的部分片段,将该片段分别连接到克隆载体pMD-18T的BamHI,XhoI酶切位点中,测定插入片段的核苷酸序列,并分别推导出其氨基酸序列。序列分析表明,不同源性大肠杆菌的AcrA的部分基因的核苷酸序列及所推导的氨基酸序列与GeneBank中该基因序列的同源性较高;不同源性大肠杆菌的AcrB的部分基因的核苷酸序列的同源性较低。所推导的氨基酸序列与GeneBank中该基因序列的同源性较高。  相似文献   

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Editor's note : The holding of the 19th Annual Meeting of the American College of Veterinary Surgeons in Philadelphia in conjunction with the Centennial Celebration of the School of Veterinary Medicine of the University of Pennsylvania provides an opportunity for reflection. Dr. Jacques Jenny, Professor of Orthopedic Surgery at the School, was Chairman of the Organizing Committee that gave rise to the American College of Veterinary Surgeons on December 16,1965, and was elected as first President of the College. The solid foundation and high ideals that the Organizing Committee established are in large part responsible for the success of the College. Dr. Jenny died on November 20, 1971. Those of us fortunate to have known him personally realize the immense gap that his premature death left. For those that did not know him, I hope that this article permits some appreciation of the contributions of Dr. Jenny the comparative orthopedic surgeon, as well as of the very special human qualities of Jacques Jenny the man. The first author, Dr. Mark Allam, was Professor of Surgery and Dean of the School of Veterinary Medicine during most of Dr. Jenny's career at the University of Pennsylvania, and was the first Chairman of the Board of Regents of the American College of Veterinary Surgeons. The second author, Dr. David Nunamaker, is the first holder of the Jacques Jenny Professorship in Veterinary Orthopedics at the University of Pennsylvania.  相似文献   

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鸡球虫微囊型疫苗的研制及免疫效果   总被引:1,自引:0,他引:1  
研制了微囊型鸡球虫疫苗并对其免疫效果进行探讨。结果表明,强毒微囊组获得的饲养效果最好,其相对增重率和相对饲料转换率分别为104.8%和100%;弱毒水剂组为74.1%和136%,而弱毒微囊组为49.4%和188%。强毒微囊组对球虫病的控制效果也明显好于其他组,其发病率、病变记分、血便记分分别为20%,6分和3分,而弱毒水剂组和弱毒微囊组分别为40%、10分、7分和50%、18分、8分。所研制的这种新型微囊球虫疫苗,具有使用方便,节省人力物力;疫苗大小适中,流动性好容易与小鸡饲料混合均匀等优点。由于微囊型球虫疫苗投服方便,因此能适合各种规模的鸡场使用,也适合鸡场进行多次或长期免疫使用。这种微囊剂型球虫疫苗的进一步完善和推广应用,可为我国鸡球虫病的免疫预防提供新的剂型。  相似文献   

7.
水分胁迫和施磷对草地早熟禾生长的影响   总被引:2,自引:1,他引:1  
通过温室水培,研究了水分胁迫和磷对草地早熟禾品种Midnight和Briuiant生长的影响,结果表明,无论水分胁迫与否,随着磷施入量的增加,植株地上部鲜重、地上部干重、地上部含水量和地下部干重均显著增加,根冠比下降。水分胁迫抑制了地上部鲜重、地上部干重、地下部干重的增加,使同等磷处理植株地上部鲜重、地上部干重、地下部干重、地上部含水量显著下降,根冠比增加。水分胁迫对抗旱品种Midnight地上部鲜重、地上部干重、地下部干重的抑制作用小于不抗旱品种Brilliant。  相似文献   

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随着社会的发展,不作为侵权责任承担的研究成为必要,文中以不作为侵权责任承担的法理基价值础作为切入点,从义务-责任原理和社会价值方面探讨了不作为侵权责任承担的基本理论,分析了其承担责任的构成要件,进而提出了一些不成熟的建议,以期对我国的侵权行为法的研究有所裨益。  相似文献   

9.
The phage typing and cultural characteristics of 574 strains of S. aureus of poultry origin in Australia were examined. With the avian phage set of Shimizu (1979) it was possible to type 74.2% of strains. A number of significant variations in the phage typing patterns of Australian strains compared to those reported from Japan and Europe were observed. A lower proportion of Australian strains were of avian phage group I and a higher proportion of group III. A high proportion of strains were of mixed lytic groups. No locally isolated phages were able to increase significantly the percentage of typeable strains, although four local phages appeared to be of greater value for phage typing poultry strains of S. aureus than some other phages of the avian phage set. The international (human) phage set was of limited value in typing Australian strains of poultry origin although four strains were identified which were indistinguishable from strains of human origin. Using cultural characteristics of the strains in conjunction with phage typing, the Australian strains of S. aureus were assigned to one of three major groups and nine subgroups. A list of typing phages considered to be valuable for use on Australian poultry strains of S. aureus is given.  相似文献   

10.
对北极狐骨骼系统进行解训观察,同时与革食动物马、牛及杂食动物猪的骨骼作形态学上的比较。由于生活习性所致,北极狐骨骼形态结构具有如下特征:北极狐的骨骼由头骨、躯干骨和四肢骨组成。头骨的主要特征是:枕骨的颈交不发达,眶上突不与颧弓相连,无眶上孔;颞骨岩部形成半球形鼓泡,鼻骨与颌前骨的鼻突之间不形成鼻颌切迹;泪骨几乎无颜面部;颌前骨的鼻突发达;上颌骨外面无面嵴;腭骨发达;犁骨腹缘后部不与鼻腔底壁接触;下颌骨支下缘无血管切迹、垂直部后下方有一角突。四肢骨的主要特征是:肩胛岗下端形成肩峰;臂骨未见三角肌结节和圆肌结节;尺骨比桡骨细长;腕骨7块;掌骨5块;指骨5指;左右髋骨几乎平行排列,坐骨弓宽平,荐结节高出荐骨;股骨有发达的大转子和较发达的小转子,缺第三转子;腓骨与胫骨等长;跗骨7块;躯干骨由7个颈椎、13个胸椎、7个腰椎、3个荐椎、15—17个尾椎组成;肋骨13对;胸骨由8个长柱状的胸骨节片和剑状软骨构成。  相似文献   

11.
First the history of the appointment for a full professorship is described in the various stages of development of the School of Veterinary Medicine Dresden. Then the significance of the habilitation degree introduced in 1903 is discussed in terms of the development of the School of Veterinary Medicine Dresden and the Faculty of Veterinary Medicine of the University of Leipzig, respectively. Commentary follows on the current discussion about the discontinuation of further development of the habilitation and possible alternatives to it, the Ph.D. and the assistant professorship.  相似文献   

12.
Development of the testis, epididymis and prostate in 53 male beagles was examined histologically with PAS-hematoxylin stain from birth to sexual maturity. The diameter of the seminiferous tubules of the testes was less than 100 microns until 20 weeks of age, however, it increased markedly between 22 and 28 week of age, reaching 180 +/- 7 (mean +/- SD) microns at 28 weeks of age. Only Sertoli cells and gonocytes (or spermatogonia) were detected in the seminiferous tubules until 16 weeks of age. Spermatocytes and spermatids appeared in the tubules at 20 and 22 weeks of age, respectively. Spermatozoa were first observed in the testes of 2 of the 5 dogs at 26 weeks of age and were found in the testes of all the 3 dogs at 28 weeks of age. The diameter of the ducts in the cauda epididymidis was 146 +/- 4 microns at 20 weeks of age. Thereafter it increased markedly, reaching 341 +/- 14 microns at 28 weeks of age. The height of the epithelium and stereocilia in the ducts of the caput epididymidis increased markedly at about 28 weeks of age. A large number of spermatozoa was seen in the lumens of the ducts of the corpus and cauda epididymidis after 32 weeks of age. The shape of the lumens in the glandular alveoli of the prostate became irregular as a result of projection of the glandular epithelium into the enlarged lumens and the epithelial cells of the alveoli became PAS-positive at 24 weeks of age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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Essential fatty acids (EFAs) exhibit the potential to affect allergic inflammation through the modulation of prostaglandin and leukotriene production, the inhibition of cellular activation and cytokine secretion as well as the alteration of the composition and function of the epidermal lipid barrier. Because of these multi-faceted effects, EFA have been proposed for treatment of canine atopic dermatitis (AD) since 1987. To date, more than 20 trials have been performed, reporting the efficacy of either oral EFA supplements or EFA-rich diets. Unfortunately, most of these studies were found to exhibit one or more of the following deficiencies: heterogeneity of diagnoses used as inclusion criteria, short duration of supplementation, lack of randomization of treatment allocation, lack of blinding of investigators and/or owners, lack of placebo or active controls, lack of documentation of plasma or skin EFA profiles during supplementation, as well as lack of standardization of the basal diets or supplements which could have provided additional EFA. Consequently, there is presently insufficient evidence to recommend for or against the use of EFA to control clinical signs of canine AD. Evidence of efficacy must await the performance of blinded, randomized and controlled trials of at least 3 months duration in which diets are identical for all of study subjects. In these trials, clinical efficacy should be evaluated in relation to plasma and cutaneous EFA treatment-induced alterations.  相似文献   

14.
本试验选择亚热带气候条件下广州地区的娟姗公牛和荷斯坦公牛各5头,比较两个品种公牛的精液品质(采精量、原精密度、原精活力、细管精液产量、冻后活力、低渗膨胀率及穿透率)。研究表明,荷斯坦公牛每次采精的采精量(16.14±0.06 mL)和细管精液产量(189.17±3.11支)都极显著地高于娟姗公牛(4.74±0.05 mL,158.46±2.64支)(P<0.01);娟姗公牛的原精密度(8.95±0.08亿/mL)极显著地高于荷斯坦公牛(8.32±0.07亿/mL;P<0.01);娟姗公牛原精活力(0.731±0.004)高于荷斯坦公牛(0.729±0.003),但两者差异不显著(P<0.05);娟姗公牛精液的冻后活力(0.355±0.003)极显著高于荷斯坦公牛(0.339±0.003;P<0.01);娟姗公牛冷冻精液的低渗膨胀率(34.50%±0.49%)显著高于荷斯坦公牛(31.21%±0.59%;P<0.01);娟姗公牛冷冻精液对去透明带仓鼠卵的穿透率(84.51%±13.83%)显著高于荷斯坦公牛(81.52%±6.13%;P<0.05)。  相似文献   

15.
青藏高原"黑土滩"退化草地植被演替规律的研究   总被引:16,自引:1,他引:15  
研究了青藏高原“黑土滩“退化过程中植被组成、群落综合特征的变化规律,探讨了退化演替的物种替代机制及恢复演替模式.结果表明,在退化演替过程中群落主要种的优势地位发生明显的替代变化.植被覆盖度、地上生物量、优良牧草产量比例随草地退化程度的加剧而明显下降.随着退化程度的加重,草地植物根系逐渐减少,草土比的比值明显减少,比值由轻度退化类型的1:5左右演变到极度退化类型的1:400左右.分析提出了“黑土滩“的形成机制、生态过程及恢复对策.  相似文献   

16.
Thirty clinically healthy dogs of two age categories were studied for the effect of long-continued training load upon the pattern of the components of the white blood picture of dogs. There is a number of changes--leucocytosis, elevation of the neutrophil granulocytes, depression of lymphocytes and eosinophil granulocytes. These changes vary with the age of the dogs. They can be considered as manifestations of myogenic reaction under physical load and under stress, and as manifestations of a gradual adaptation in the course of training. The results can be included in the set of tests within the scientific system of dog training.  相似文献   

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In six heifers without sexual organs the effects were compared of the superanalogues LH-RH [(D-Tle6) and (D-Trp6)] on the secretion of luteinizing hormone (LH) and follicles of stimulating hormone (FSH). The superanalogues were given i. m. at dosages of 10, 50 and 100 micrograms pro toto. Dosages of 50 and 100 micrograms of both superanalogues had a greater effect on the secretion of LH than the dosage of 100 micrograms. The highest average concentration of LH during the time of application (D-Tle6) was recorded in the dosage of 10 micrograms (7.84 ng.ml-1). The average concentrations of LH after application (D-Trp6) were within the range of 5.46 to 9.29 ng.ml-1. Because of the great variability of the concentrations of LH no significant differences were ascertained due to the influence of dosage. From a comparison of the concentrations of LH with the same dosage it emerged that (D-Trp6) after an application of 50 micrograms significantly increased the concentration of LH from the 60th to the 240th minute and thus had a more protracted effect. With dosages of 10 and 100 micrograms of the superanalogues no statistically significant differences were recorded after two hours from application. With (D-Trp6) the higher stimulative effect on the secretion of LH was statistically confirmed. The highest concentrations of follicles of stimulation hormone (FSH) (204.6 and 228.6 ng.ml-1) were found from the 40th to the 100th minute after the application of dosages of 50 and 100 micrograms (D-Tle6). The protracted effect was greatest with a dosage of 100 micrograms (270 mins). (D-Trp6) at a dosage of 100 micrograms caused the greatest effect on the secretion of FSH (226.8 ng.ml-1 for a period of 180 mins). The lower dosages of analogues scarcely differed in response. The dosage of superanalogues has an influence on the concentration of FSH in peripheral blood and on the duration of the protracted effect.  相似文献   

19.
The cloning of livestock is performed by the nuclear transfer of early embryonic stages into prepared oocytes in order to obtain a high number of genetic identical animals. As the most important technical steps there are maturation and enucleation of the oocytes, isolation of single blastomeres or karyoplasts of the donor embryo, transfer of the nucleus-containing membrane vesicle under the zona pellucida of the recipient cell, and fusion of the recipient cell and blastomere or karyoplast. Until now, the largest clone which is known exists of seven bulls. The efficiencies of the particular methodical steps have to be improved. More knowledge of the activation of oocytes, nucleus differentiation and availability of determined cell cycle-stages of mitosis is required. The combination of embryo cloning, cryopreservation of embryos and non-surgical embryo transfer is required for basic research and animal breeding.  相似文献   

20.
Uterine motility may have significance for the transportation of spermatozoa and the elimination of the ejaculate and inflammatory products after mares have been covered. The effect of some of the component stimuli of coitus on uterine contractions was investigated by using M-mode ultrasound. The number, amplitude and duration of the uterine contractions of each uterine horn and of the uterine body were measured in oestrous mares for four minutes before and four minutes after teasing by a stallion, mechanical stimulation of the vagina and cervix, the intrauterine infusion of 80 ml of sterile saline, the intrauterine infusion of 10 ml of sterile saline, the intrauterine infusion of 150 ml of sterile saline, and the transcervical passage of a uterine catheter. Teasing by a stallion did not affect the total number, mean amplitude or mean duration of the uterine contractions. Mechanical stimulation of the vagina and cervix increased the total number of uterine contractions, but did not affect the amplitude or duration of the contractions. The intrauterine infusion of 80 ml of sterile saline resulted in an increase in the total number of contractions and a significant increase in the mean amplitude and the mean duration of the contractions in the uterine horns but not the uterine body. The intrauterine infusion of 10 ml of sterile saline caused a significant decrease in the number of uterine contractions in the uterine horns, but had no effect on the contractions of the uterine body. The infusion of 150 ml of sterile saline reduced the number of contractions in the uterine horns but not the uterine body, and did not affect the mean amplitude and mean duration of the contractions. The transcervical insertion of a catheter reduced the number of contractions in the uterine horns, but did not affect the amplitude or duration of the uterine contractions.  相似文献   

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