خيارات البحث
النتائج 111 - 120 من 445
Effects of ascorbic acid on proliferation and biological properties of bovine chondrocytes in alginate beads
2003
Kim, G. (Hokkaido Univ., Sapporo (Japan)) | Okumura, M. | Bosnakovski, D. | Ishiguro, T. | Park, C.H. | Kadosawa, T. | Fujinaga, T.
Bovine chondrocytes were cultured in monolayers and alginate beads with or without ascorbic acid (Asc) for 16 days. Cell proliferation was examined every 4 days by staining with Hoechst 33258 dye. The gene expression of aggrecan, and collagen type I and II was analyzed at 16 days by reverse transcription and polymerase chain reaction.Cell morphology and the production of extracellular matrix (ECM) were evaluated by cytochemical, immunocytochemical and electron microscopical methods.Cells were continuously cultured in alginate beads with Asc for 2 months, and the cell morphology and ECM were examined. The proliferation of chondrocytes was significantly stimulated with Asc in both monolayers and alginate beads at 16 days. Expression of the collagen type I gene in both cultures was increased, and that of the collagen type II gene in alginate beads was decreased, by Asc. There were no significant cytochemical and immunocytochemical differences between the cultures in alginate beads with or without Asc at 16 days.In alginate beads cultured with Asc for 2 months, proliferating cells were observed mainly at the periphery of the beads, and glycosaminoglycan and collagen type II were found around the cells. These results suggest that Asc stimulated the proliferation of chondrocytes and maintained the chondrogenic properties of the cells in an alginate beads culture.
اظهر المزيد [+] اقل [-]Hepatocyte growth factor transduces different intracellular signals in aortic and umbilical venous endothelial cells
2003
Makondo, K. (Hokkaido Univ., Sapporo (Japan)) | Kimura, K. | Kitamura, T. | Yamaji, D. | Saito, M.
Endothelial cells are important for maintenance of vascular integrity by producing a variety of bioactive molecules such as nitric oxide (NO) . Recent evidence has suggested that there are some differences in characteristics between endothelial cells from different origins. Here we examined responses of two typical endothelial cells to hepatocyte growth factor (HGF), which induces endothelium-dependent relaxation of microvessels. Stimulation of human umbilical vein endothelial cells (HUVEC) and bovine aortic endothelial cells (BAEC) with HGF increased endothelial NO synthase activity, accompanied with an increase of activity-related site-specific phosphorylation of protein kinase B/Akt. However, HGF stimulated phosphorylation of p38 mitogenactivated protein kinase (MAPK) only in HUVEC, but not in BAEC, while it induced phosphorylation of p44 /p42 MAPK in both cells. These results suggest that HGF transduces different intracellular signals between aortic and umbilical venous endothelial cells, and that the differences might represent divergent endothelial responses to growth factors, especially those that activate receptor-tyrosine kinases.
اظهر المزيد [+] اقل [-]Growth pattern and seasonal weight changes of the feral raccoon (Procyon lotor) in Hokkaido, Japan
2003
Asano, M. (Hokkaido Univ., Sapporo (Japan)) | Matoba, Y. | Ikeda, T. | Suzuki, M. | Asakawa, M. | Ohtaishi, N.
Development of enzyme linked immunosorbent assay for seromonitoring against hydropericardium syndrome (ELISA) virus
2003
Manzoor, R. | Kamal, T. | Khawaja, D.A. | Ismail, M.A. | Gill, Z.J. (Veterinary Research Inst., Lahore (Pakistan))
In this study ELISA was standardized for detecting antibodies against Hydropericardium Syndrome Virus. Factors like Antigen, Conjugate and incubation time were studied. Standardization was carried out by checker board titration method. Optimum incubation time for colour development was found to be 15 minutes while 50 mug/ml of antigen gave better results than 100 mug/ml. The conjugate dilution of 1:500 was observed to give satisfactory results as determined by regression analysis. Cut off value was determined by adding 2SDs and 3SDs in the mean optical density (OD) values of negative serum samples. It was found that mean OD+2SD (0.0684) resulted in better diagnostic sensitivity) and diagnostic specificity than mean OD+3SDs (0.0741).
اظهر المزيد [+] اقل [-]Estimation of serum glucose, cholesterol and uric acid contents and proximate analysis of meat in different strains of chickens
2003
Bhatti, B.M. | Talat, T. | Sardar, R. (Poultry Research Inst., Rawalpindi (Pakistan))
In this study five samples each of serum glucose, serum cholesterol and uric acid contents were measured in Fayoumi, Rhode Island Red, Parent desi, desi Fl and desi F2 strains of chickens. Cholesterol contents were found to be lowest in desi F2 chickens whereas in other strains there was least significant difference, which can be attributed to reduced lipogenic activity in desi F2 generation. When five samples each of meat from two locations i.e. breast and thigh was subjected to proximate analysis it was found that there was no difference (P greater than 0.05) in crude protein, crude fat, total ash and moisture contents regardless of sex and strains. Dry matter contents differed (P less than 0.05) in breast meat and found to be lowest in Parent desi stocks.
اظهر المزيد [+] اقل [-]Growth performance of different varieties of desi generation-I chickens maintained under deep litter system
2003
Sahota, A.W. | Bhatti, B.M. (Poultry Research Inst., Rawalpindi (Pakistan))
This study was conducted to examine growth performance of black, dark brown and light brown varieties of Desi Generation-1 chickens obtained from selected Desi parents (originally procured from rural areas of Mianwali and Bhakkar districts) maintained at Poultry Research Institute, Rawalpindi. A total number of 900 day-old Desi chicks 300 each of black, dark brown and light brown varieties were divided into 3 separate groups and further sub-divided into 3 equal replicates. The experimental chicks were maintained on littered floor in 9 separate pens under optimal managemental conditions for a period of 12 weeks. They were fed ad libitum a balanced chick starter ration (from day- old to 8 weeks) and a grower mash (from 9 to 12 weeks). The birds had free access to clean and fresh drinking water. The results showed non- significant difference in growth rate, feed intake and feed conversion efficiency (feed/kg gain), whereas, significantly (P less than 0.05) lower mortality rate was recorded in Desi light brown chicks in comparison to other two varieties. The better growth performance in different varieties of Desi chicks observed during the present study than reported in earlier findings could be due to effect of genetic improvement through selection breeding carried out in the parent Desi flock.
اظهر المزيد [+] اقل [-]Effect of freezing on moisture, protein, fat and ash contents of broiler meat
2003
Bhatti, B.M. (Poultry Research Inst., Rawalpindi (Pakistan)) | Hafeez, F. | Bano, S. | Talat, T. | Sardar, R. | Akhtar, S.
This trial was conducted to study effect of freezing on quality of broiler meat after freezing. Meat samples were taken from two sites such as breast and thigh. The weight, moisture, protein, fat and ash contents were analyzed before and after freezing at -25 degree centigrade for 15 days using methods given in AOAC, (1990). It was observed that protein, fat and ash contents were not changed consequent to freezing. There was loss (P less than 0.05) in weight which can be attributed to drip loss when meat is thawed. This study provided evidence that there is no change in nutrients when meat is subjected to freezing.
اظهر المزيد [+] اقل [-]Proportion of edible and non edible body parts in different strains of laying chickens
2003
Bhatti, B.M. | Anjum, A.R. | Bhatti, S.U. (Poultry Research Inst., Rawalpindi (Pakistan))
This study was conducted to ascertain anatomical variation in different body parts of Desi, Fayoumi, Cross (Rhode Island Red x Fayoumi) and Nick Chick laying hens. A total 16 laying hens of average body weight were selected using random numbers out of 2600 laying hens, slaughtered and eviscerated. It was observed that proportion of neck, ribs, breast, back, wings, thigh and legs out of aggregate weight was highest (51.74 plus minus 2.85) in Fayoumi hens. The proportion of liver, gizzard, heart and spleen combined weight was highest (6.05 plus minus 1.81) in desi hens. The proportion of non edible offals including trachea, lungs, kidneys, blood, feathers, head, crop, proventriculus, intestines, shanks, gizzard waste, skin, tail, testes, ova, oviduct and fat was estimated to be highest i.e. 46.60 plus minus 1.16 in Nick Chick laying hens. The anatomical variation in Desi and Fayoumi chicks was attributable to scavenging habit of these birds. The high proportion of edible offal in commercial Nick Chick hens may be ascribable to higher productive and reproductive traits.
اظهر المزيد [+] اقل [-]Studies on the thermostability of vero cell adapted rinderpest virus vaccine
2003
Asim, M. | Noor, M.S. | Zulfiqar, M. | Hussain, A. | Raza, M.A. (Veterinary Research Inst., Lahore (Pakistan))
This study was conducted to determine the optimum storage temperature for Rinderpest vaccine prepared on vero cells to know the shelf life of the vaccine. The vials were randomly selected from one batch of the vaccine, titrated and stored at minus 20 degree centigrade (Freezer), 4 degree centigrade (refrigerator) and room temperature. The titre was found to be 105.1 per ml. The vials stored at minus 20 degree centigrade & 4 degree centigrade were subjected to titration after an interval of six months for 3 and 2 years respectively. The vials stored at room temperature were tested after 4 weeks, 8 weeks and 12 weeks. Titration results indicated that the titre of the vaccine vials stored at room temperature decreased by 100.9 101.2 and 101.6 after storage time of 4 weeks, 8 weeks and 12 weeks respectively. The vials stored at 4 degree centigrade maintained their titre for a period of six months but after that the loss in titre was 100.4, 101.0, and 102.4 after storage time of one, one and half and two 2 years respectively. The vaccine vials stored at minus 20 degree centigrade maintained their original titres (initial titre of the vaccine) even after the storage for three years. It is concluded that vero cell adapted Rinderpest virus vaccine can be stored at 4 degree centigrade for a period of six months, however, at 20 degree centigrade it can be stored for three years without any adverse effect on titre.
اظهر المزيد [+] اقل [-]Recent advances in sheep breeding
2003
Hanif, M. (Directorate of Planning and Evaluation, Lahore (Pakistan)) | William, H.L.
The effects of melatonin and Light treatments on the reproductive performance of yearling Suffolk rams were investigated. The two groups (A, n = 8; B, n = 8) were given a priming period of long days (18 h Light (L): 6 h dark (D) during 1st February to 14th March. During 14th March to 9th September, group A was exposed to local light + melatonin Implants (Regulin) at 5 weekly intervals, group B was exposed to local light + melatonin Fed (M- 5250) alongwith the feed. The group (C, n = 8) in the local light during 1st February to 14th March and during 14th March to 9th September remained on local light + melatonin implants (Regulin) at 5-weekly intervals. However, the group (D, n=8) was treated as control and kept on local light environment (Lat. 51 degree 43'N) throughout the experiment. Testis diameter, sexual behaviours and semen quality were used to assess reproductive performances. The treatment to group A & B resulted in a significant advancement in high reproductive performance. The treatment to group C indicated that the abrupt application of melatonin in mid March resulted in a weak response in terms of all the criteria of assessment. The investigation indicated that seasonal fluctuations in reproductive behaviour and semen quality may be rephrased by the application of light and melatonin treatments and that these treatments may be considered for the preparation of rams for out of season breeding.
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