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排序方式: 共有1255条查询结果,搜索用时 15 毫秒
911.
912.
H M Eissa A S Ahmed B H Serur M A el-Sayed 《Archiv fuer experimentelle veterinaermedizin》1990,44(4):621-625
6 pregnant Baladi goats underwent general anaesthesia, using thiopental sodium. Intravenous application of 10-15 mg/kg body weight of thiopental sodium in 2.5% solution produced light anaesthesia for about 20 minutes. The effect of general anaesthesia on progesterone and cortisol levels was studied before and during the application of anaesthesia as well as 1/2, 1, 4, and 24 hours after anaesthesia. Progesterone was determined by RIA and cortisol by competitive protein binding reaction. Decrease in progesterone and rise in cortisol were noticed during and after anaesthesia. 4 of 13 foetuses were aborted 1-2 weeks after the application of anaesthesia. 6 were born dead. 2 died few hours after birth, and 1 stayed alive. 相似文献
913.
Calves were infected with 25,000 or 50,000 viable eggs of Taenia saginata. Larval numbers ranged between 2077 and 6005. During infection the animals developed leucocytosis, which was mainly due to lymphocytosis. An apparently positive correlation was observed between the lymphocytosis and the in vitro proliferative response of the lymphocytes to antigen prepared from proglottids. Maximal in vitro blast transformation of the cells stimulated with antigen occurred on Days 12 and 32 post-infection (p.i.). Specific antibodies to T. saginata were demonstrated on Day 14 p.i. At that time, the proliferative response of the cells paralleled the formation of specific antibodies, particularly of the IgG class. The stimulated cells produced a lymphokine showing interleukin 2 (IL 2)-like activity, since the addition of supernatant of such cells to IL 2-dependent concanavalin A (Con A)-blast cells supported the in vitro growth of the cells. In addition, peripheral blood lymphocytes (PBL) specific for T. saginata could be maintained in long-term cultures when they were cultured in medium containing supernatants of MLA-144 cell lines. The data presented in this study indicate that cells specific for T. saginata produced and consumed T cell growth factor (TCGF). 相似文献
914.
In vitro culture of mouse preantral follicles using membrane inserts and developmental competence of in vitro ovulated oocytes 总被引:3,自引:0,他引:3
Adam AA Takahashi Y Katagiri S Nagano M 《The Journal of reproduction and development》2004,50(5):579-586
To develop a reliable follicle culture system, mouse preantral follicles 150-200 microm in diameter were cultured individually for 5 or 6 days in membrane inserts or in droplets, and then induced to ovulate with hCG (Experiment 1). The nuclear maturation and developmental competence of the oocytes that ovulated from the follicles cultured in inserts were determined (Experiment 2). There was no significant difference between the two culture systems in the survival rate (83 and 77%). However, follicles cultured in inserts showed a higher ovulation rate (63%) than those cultured in droplets (39%, P<0.05). About 80% of the oocytes that ovulated from the follicles cultured in inserts were at the metaphase II stage. After in vitro fertilization, 75 and 48% of in vitro ovulated oocytes cleaved and developed into blastocysts, respectively. These results demonstrate that the insert culture system is superior to the droplet culture system in terms of follicular growth and ovulation, and can be used to investigate the growth and ovulation of follicles in vitro. 相似文献
915.
Daoubi M Durán-Patrón R Hmamouchi M Hernández-Galán R Benharref A Collado IG 《Pest management science》2004,60(9):927-932
An efficient, one-pot synthesis of angular and linear dihydropyranocoumarins, along with C-6 and C-8 prenylated coumarins is reported. These compounds, together with single- and furanocoumarins, were tested for their potential antifungal activity against the phytopathogen Botrytis cinerea Pers ex Fr. The results show that furanocoumarins may be able to control the fungus B cinerea. 相似文献
916.
917.
Amira M. K. Abouelella Yasser E. Shahein Sameh S. Tawfik Ahmed M. Zahran 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(4):341-351
Echinacea (E.) purpurea herb is commonly known as the purple coneflower, red sunflower and rudbeckia. In this paper, we report the curative efficacy of an Echinacea extract in γ-irradiated mice. E. purpurea was given to male mice that were divided into five groups (control, treated, irradiated, treated before irradiation & treated after irradiation) at a dose of 30 mg/kg body weight for 2 weeks before and after irradiation with 3 Gy of γ-rays. The results reflected the detrimental reduction effects of γ-rays on peripheral blood hemoglobin and the levels of red blood cells, differential white blood cells, and bone marrow cells. The thiobarbituric acid-reactive substances (TBARs) level, Superoxide dismutase (SOD) and glutathione peroxidase (GSPx) activities and DNA fragmentation were also investigated. FT-Raman spectroscopy was used to explore the structural changes in liver tissues. Significant changes were observed in the microenvironment of the major constituents, including tyrosine and protein secondary structures. E. purpurea administration significantly ameliorated all estimated parameters. The radio-protection effectiveness was similar to the radio-recovery curativeness in comparison to the control group in most of the tested parameters. The radio-protection efficiency was greater than the radio-recovery in hemoglobin level during the first two weeks, in lymphoid cell count and TBARs level at the fourth week and in SOD activity during the first two weeks, as compared to the levels of these parameters in the control group. 相似文献
918.
919.
Abdelhadi Hammi Amina Bennani Ahmed El Ismaili Yamina Msatef Mohamed Najib Serrhini 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(5):553-556
One hundred and eight isolates of Phytophthora infestans were collected from infected potato and tomato crops in the middle-north of Morocco during 1997–2000. Pairings of these isolates with tester isolates of mating type A1 and A2 revealed that 60% of the isolates were mating type A2 (65/108) and 40% were mating type A1. After 10 days incubation at 20 °C and a 16-h photoperiod, approximately 25% and 18% of the oospores produced in-vitro germinated in potato soil extract and potato root extract, respectively. Oospores were observed in potato leaf tissues in pairings that were fertile in-vitro. Maximum production of oospores was obtained in potato leaves of cultivars that were moderately susceptible (Desirée, Nicola) after 10 days of incubation at 15 °C and a 16-h photoperiod. These results confirm the presence of P. infestans strains that are sexually compatible under Moroccan climatic conditions. Production of oospores constitutes a threat for these crops because of the occurrence of recombinants with new virulences which may be difficult to control and as a consequence survival of oospores in absence of the host plant in the soil. 相似文献
920.
Expression profile of myostatin mRNA during the embryonic organogenesis of domestic chicken (Gallus gallus domesticus) 总被引:2,自引:0,他引:2
Sundaresan NR Saxena VK Singh R Jain P Singh KP Anish D Singh N Saxena M Ahmed KA 《Research in veterinary science》2008,85(1):86-91
Myostatin is a potent growth and differentiation factor involved in skeletal muscle tissue formation in vertebrates. However, recent studies in chicken embryo suggested that the myostatin was expressed even before the establishment of myogenic lineage. No studies have thus far been reported in birds to define the role of myostatin during the embryonic organogenesis. The present experiment was designed for studying the expression profiles of myostatin mRNA in the chicken liver, heart, brain, and intestine during their morphogenesis, using real-time PCR. The myostatin mRNA expression was significantly upregulated in liver during E15-E18. Similar results were observed during the development of chicken heart. In brain, the expression of myostatin was upregulated from E4 onwards. In intestine, the expression of myostatin was significantly increased many folds on E9-E18. Therefore, the increase in myostatin expression might be related to the growth of liver and heart on days E12-E18; morphogenesis and growth of brain during E15-E18; and morphogenesis and differentiation of intestine during E9-E18. In the present study, the tissue-specific expression of myostatin gene in chicken is similar to fishes, but different from that in mammals. Further, the inspection of chicken genome also suggested that there is no differentiation of GDF-8 and -11. A recent finding suggests that the chicken myostatin gene is closely related to mammals than fishes. Therefore, we propose that the chicken myostatin gene might have diverged in its function between teleosts and mammals. Indeed it is possible that its function might have only become fully differentiated to serve as a control of muscle mass in mammals. 相似文献