首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
Glaucoma and inherited retinal degeneration/dystrophy are leading causes of blindness in veterinary patients. Currently, there is no treatment for the loss of vision that characterizes both groups of diseases. However, this reality may soon change as recent advances in understanding of the disease processes allow researchers to develop new therapies aimed at preventing blindness and restoring vision to blind patients. Elucidating the molecular mechanisms of retinal ganglion cell death in glaucoma patients has led to the development of neuroprotective drugs which protect retinal cells and their function from the disastrous effects of elevated pressure. Identification of the genetic mutation responsible for inherited degenerations and dystrophies of the outer retina has enabled researchers using gene therapy to restore vision to blind dogs. Other patients may benefit from retinal transplantation, stem cell therapy, neuroprotective drugs, nutritional supplementation and even retinal prostheses. It is possible that soon it will be possible to restore sight to some blind patients.  相似文献   

3.
4.
5.
1. The effects of egg turning upon the formation of sub‐embryonic fluid (SEF), and albumen weight and composition are described up to day 8 of incubation.

2. The density of albumen increased, and the density of yolk sac contents decreased, during the first 5 d of incubation. Failure to turn eggs diminished these changes.

3. The rate of formation of SEF and its maximum weight were lower if eggs were not turned, as was the rate of decrease in albumen weight.

4. The concentration of sodium and chloride, as well as osmolality, were higher in SEF than in thin albumen, and were affected by a failure to turn eggs.

5. Static incubation altered the concentrations of yolk nutrients in SEF.

6. It is concluded that the formation of SEF is primarily dependent upon the transfer of sodium and chloride from albumen to SEF so creating an osmotic force for water movement in the same direction. Turning the eggs promotes this process by ensuring an adequate supply of ions in thin albumen adjacent to the blastoderm.  相似文献   


6.
Selecting 6 heads of new yak strains(the offspring of reciprocal cross of F1 produced by wild yak male mated with domestic yak female)and 6 domestic yaks at 3 and 12 age in months respectively at Datong Yak Farm of Qinghai Province. This paper was studied for the morphological characteristics of the skin and hair coat of yak and their adaptability to the cold living environment in Qinghai-Tibetan plateau. The results indicated that it should be of vital importance marker for the morphological characteristics of the skin and hair coat with two type of yaks at 3 and 12 age in months and their regulations of growth and development to adapt to the cold living environment in Qinghai-Tibetan plateau,The main morphological indexes of the skin and hair coat of the rearing new yak strain were higher than those of the domestic yaks at the same age in months, or speak precisely, the new yak strain was more powerful adaptable to the alpine cold living environment than that of the domestic yaks. The resvlts above provided scientific basis for the native strain breeding of yak and the new yak strain rearing.  相似文献   

7.
The expression pattern of several intermediate-filament proteins (vimentin, cytokeratin 8, 18 and 19) and the basal lamina component laminin was investigated in the Wolffian and the Müllerian ducts of bovine embryos and fetuses. The material studied comprised sexually undifferentiated stages [crown-rump length (CRL) 0.9 cm/1.0 cm/1.2 cm/1.9 cm/2.5 cm] and female stages (CRL 3.0 cm/4.2 cm/5.1 cm). Laminin could be demonstrated in the basal lamina of the developing Wolffian and Müllerian duct as well as in the stroma surrounding the Müllerian duct. The intermediate-filament protein vimentin was expressed in the mesothelium of the funnel field and in the epithelium of the Müllerian duct in all studied specimens, whereas the epithelial cells of the Wolffian duct only showed vimentin expression from a CRL of 2.2 cm onwards. In the cranial part of the Müllerian ducts only a few cells stained with pan-cytokeratin antibodies, whereas mesothelium and epithelium of the Wolffian duct showed as distinct immunostaining in all investigated stages. Both genital ducts showed no immunostaining with the antibody against cytokeratin 19 at any time of development. We conclude from our immunohistochemical results that the epithelial cells of the Wollfian duct do not contribute cells to the developing Müllerian duct.  相似文献   

8.
9.
10.
11.
12.
Blowfly strike and the methods used to combat blowfly strike were recorded on 33 properties in the R?ens area of South Africa during 2003/2004. Data were recorded on Merino and Dohne Merino hoggets (n = 4951) with at least 3 months' wool growth. The following data were captured: presence or absence of strike, site of the strike (body or breech), presence or absence of dermatophilosis as well as subjective scores for wool quality and wool colour. Control measures recorded include: chemical treatment (preventative and spot treatment), crutching, mulesing and the use of the Lucitrap system. Blowfly strike was not significantly influenced by gender or breed. Hoggets suffering from dermatophilosis were more likely to be struck, compared with contemporaries not suffering from the skin disorder (0.057 vs 0.027; P < 0.05). Merino hoggets generally had higher scores than their Dohne Merino contemporaries for wool quality (32.6 vs 27.4; P < 0.05) and wool colour (29.0 vs 27.2; P < 0.05). There was an indication that the Lucitrap system may have reduced flystrike, but the effect was not statistically significant (P = 0.19 for overall strikes and P = 0.12 for body strike). The Mules operation benefited overall flystrike (0.013 vs 0.110; P < 0.05); mainly through an effect on breech strike (0.010 vs 0.109; P < 0.05). The proportion of fly strikes increased with wool length, and declined with an increase in farm size in wool colour score. None of the ethically acceptable control measures assessed could substantially reduce blowfly strike on their own, and an integrated pest management programme was proposed.  相似文献   

13.
14.
Summary

The experiments demonstrate that the acid‐base status of porcine blood does not change significantly during a six hours’ storage period at 0° C. They further show that the sampling of blood via a vena cava puncture in comparison with sampling via an indwelling ear vein catheter is associated with severe stress that affects the acid‐base statuts of the blood.  相似文献   

15.
1. An investigation was conducted among the progeny from crosses between Silver‐Spangled and Gold‐Pencilled Hamburgh bantams, and between Silver‐Spangled Hamburgh and Double‐Laced Barnevelder bantams.

2. Two subjects were studied: the relationship between three plumage pattern phenotypes, spangling, transverse‐barring and double‐lacing, all of which are arrangements of eumelanin expressed on a background of phaeomelanic pigmentation and the inheritance of the marbled chick down of the Silver‐Spangled Hamburgh bantam.

3. Examination of the F2 generations demonstrated that, in conjunction with silver (S) gene(s) and extended black (E) alleles at the E‐locus the silver‐spangled phenotype can be produced by the addition to the genotypes of the Gold‐Pencilled Hamburgh, homozygous ebc (Db‐ml+‐Pg), and Double‐Laced Barnevelder, homozygous eb (db+‐Ml‐Pg), of Sp and Db genes respectively. Consequently Sp and Ml are one and the same gene, for which I retain the symbol Ml, and the genotype of the Silver‐Spangled Hamburgh is homozygous E (Db‐Ml‐Pg), where the buttercup (ebc) and brown (eb) are alleles of the E‐locus and Db, Ml, Sp and Pg are respectively the eumelanin restrictor dark‐brown Columbian, the eumelanin extension melanotic, plumage pattern spangling and the pattern gene.

4. The exact correlation between S/‐ E/E Db/Db and the marbled chickdown phenotype demonstrated the latter to be a pleiotropic effect of Db/Db, thus enabling the mapping of Db, Ml and Pg in group 3 on chromosome 1.  相似文献   


16.
17.
18.
In order to explore the characteristics of nutrient contents and scientifically evaluate the nutritional value of the alpine grassland plants in the source area of the Yellow River, the plants of the five different alpine grasslands were selected as the research objects, and the content of crude protein (CP), ether extract (EE), crude fiber (CF), crude ash (CA), total phosphorus (TP) of the plants were determined. At the same time, the principal component analysis method was used for quantitative comprehensive evaluation of the plants nutritional value. The results showed that the CP content of the plants in all alpine grasslands was between 12.78%~15.35%, the EE content was between 2.63%~3.38%, the CF content was between 17.56%~25.16%, the CA content was between 5.52%~11.53% and the TP content was between 0.11%~0.27%. The order of nutrient value of plants in different alpine grassland from high to low was: degraded alpine meadow > native alpine meadow > swamp meadow > degraded alpine steppe> native alpine steppe;The order of yield per unit area of the total nutrients of plants in different alpine grasslands from high to low was: swamp meadow > native alpine meadow > native alpine steppe> degraded alpine steppe> degraded alpine meadow;The order of nutrient value of different plant species from high to low was: Leguminosae>Forbs >Cyperaceae>Gramineae. © 2019 Authors. All rights reserved.  相似文献   

19.
1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.  相似文献   


20.
Hayashi  S.  Jinbo  T.  Iguchi  K.  Shimizu  M.  Shimada  T.  Nomura  M.  Ishida  Y.  Yamamoto  S. 《Veterinary research communications》2001,25(2):117-120
The concentrations of C-reactive protein (CRP) and 1-acid glycoprotein (AAG) were evaluated in 1-, 3- and 18-month-old dogs (four of each age) that had been inoculated with turpentine oil. The CRP and AAG in 3-month-old and younger dogs subjected to surgery or inoculated with either Staphylococcus aureus or a viral vaccine were also evaluated. The average CRP concentration in the sera peaked 2 days after inoculation of turpentine oil. The peak CRP concentrations in 3- and 18-month-old dogs were significantly (p<0.05) greater than those in 1-month-old dogs. The average AAG concentration in the sera peaked 4 days after inoculation of turpentine oil. No significant difference was found in AAG concentrations between any of the age groups. When experimentally inoculated with S. aureus or subjected to oophorohysterectomy, the CRP and AAG concentrations increased in 3-month-old dogs, but they increased little in 1-month-old dogs. The CRP and AAG in dogs inoculated with the viral vaccine did not increase. In dogs with fractures or subjected to percutaneous gastrostomy, the CRP and AAG concentrations correlated with the condition of dogs.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号