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121.
Surface ultrastructural observation of the thyroid gland in donkey revealed the coexistence of certain unusual follicles or cysts, the ultimobranchial (UB) follicles, which exhibited large diameters and less regular outlines. In addition, several small follicles, cell nests or solid cellular masses were also demonstrated in association with these structures. Surface of most UB follicular cells was almost hexagonal in shape, studded with sparse or dense pleomorphic microvilli, which were much denser at the cellular borders. Each follicular cell bore single cilium that projecting over the cell surface. Interestingly, bleb-like apocrine protrusion of the apical cytoplasm of some follicular cells was frequently demonstrated. These apocrine blebs (or aposomes) were varied in shape, size and showed smooth or irregular surface. In addition to such aposomes, deep to shallow circumscribed or eroded areas of the apical cell surface was frequently demonstrated. These findings indicate that the UB follicular cells in donkeys, similar to those of camels, exhibit an apocrine activity alongside with the usual merocrine mode of secretion. 相似文献
122.
Medan M Shalaby AH Sharawy S Watanabe G Taya K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(1):83-85
The induction of estrus during the non-breeding season was investigated in 100 Egyptian Baladi goats (Capra hircus). All animals assigned to treatments had low progesterone concentrations (<0.5 ng/ml) tested 2 times 10 days apart to confirm anestrous condition. Animals were assigned to three experimental groups. A group of animals received subcutaneous norgestomet ear implant for 11 days and a single i.m. injection of PGF2alpha 24 hr before implant removal (group I; n=40). Second group of animals received subcutaneous norgestomet ear implant for 11 days and a single i.m. injection of PGF2alpha 24 hr before implant removal and gonadotropin releasing hormone 24 hr after implant removal (group II; n=40). Third group of animals received no treatment (control group; n=20). The percentage of goats that showed estrous behavior during the first 72 hr after implant removal was 77.5, 85.0% and 10.0% in group I, group II and control group, respectively. The fertility rate was 57.5, 70.0% and 10.0% in group I, group II and control group, respectively. In conclusion, estrus can be induced in seasonally anestrous Egyptian Baladi goats using norgestomet and PGF2alpha and the injection of GnRH 24 hr after norgestomet implant removal synchronized ovulation in a higher percentage of goats. 相似文献
123.
Two experiments were conducted to further clarify the importance of cell-mediated immunity in cases of canine demodectic mange. Pups obtained from pregnant pedigreed beagle bitches were exposed to mites (Demodex canis Leydig, 1859) and then injected with rabbit anticanine lymphocyte serum (ALS). Littermates received either mites alone, ALS alone, or were retained as negative controls. Squamous lesions of demodicosis developed in all pups receiving both ALS and mites as well as in two pups receiving only mites. No lesions were observed in any of the remaining pups. A marked decline in the number of peripheral lymphocytes developed in pups receiving ALS. These cells returned to normal numbers 3 weeks after treatment was discontinued. The squamous lesions on affected pups continued to coalesce until generalized demodicosis became established. Spontaneous resolution of mite-infested areas was never observed and pustular lesions did not develop.It was concluded that the cellular immune system of the dog, functioning as a defense mechanism against the establishment and proliferation of D. canis, is of paramount importance in preventing the development of demodectic mange. 相似文献
124.
The T-lymphocyte mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) were used as skin test agents to assess the cellular immune competence of dogs with demodectic mange. The intradermal injection of either mitogen into the abdomen of dogs produced a local erythematous and indurated papule characteristic of a delayed hypersensitive response. The mean diameter of the reaction at 24 and 48 following injection was significantly smaller in eight demodectic dogs than in eight dogs free from mite infestation (P < 0.05). This suppressed response suggested that dogs with demodicosis may have a hypoactive cellular immune system rendering them less capable of combating invading demodicids.The intradermal injection of PHA and Con A also produced an immediate wheal reaction. The mean diameter of the wheal after 15 min was significantly larger in demodectic dogs than in the control animals (P < 0.05). A possible reason for this difference and a potential mechanism for the reaction are discussed. 相似文献
125.
Makled M. N. Abouelezz K. F. M. Gad-Elkareem A. E. G. Sayed A. M. 《Tropical animal health and production》2019,51(8):2333-2342
Tropical Animal Health and Production - This study was conducted to assess the effects of early dietary supplementation with probiotic, yoghurt, and sodium butyrate (SB) on the growth performance,... 相似文献
126.
Laila A. Mohamed Mohamed M. El‐Hindawy Mahmoud Alagawany Ayman S. Salah Sabry A. A. El‐Sayed 《Journal of animal physiology and animal nutrition》2019,103(5):1380-1387
This study was to investigate the effect of dietary protein levels and supplementation with two cold‐pressed oils on the performance, immunity and antioxidant indices of growing Japanese quails. A 3 × 4 factorial experiment, using 3 dietary crude protein (CP) levels (22%, 24% and 26%) and 4 supplemental herbal oils levels: control without additives, 250 mg marjoram (Mar), 250 mg thyme (Thy) and 125 mg Mar + 125 mg Thy per kg diet. A total of 720 unsexed, 7‐day‐old quail chicks were randomly distributed into twelve treatment groups (4 replicates per group of 15 chicks in each). The live body weight (LBW) on 42 days and body weight gain (BWG) from 7 to 42 days were significantly improved (p < 0.01 and 0.05) in chicks fed 24% or 26% CP compared with those of the 22% CP group. The groups fed diets supplemented with Mar or in combination with Thy oil exhibited significantly better LBW, BWG and feed conversion ratio (FCR) than the control at all periods except BWG from 21 to 42 days and FCR from 7 to 21 days were not significant. Feed intake was gradually decreased with increasing dietary CP level or adding herbal oils during the periods 21–42 and 7–42 days of age. Plasma triglycerides, cholesterol, total lipids and malondialdehyde were decreased by cold‐pressed oils supplementation, but the activity of reduced glutathione and superoxide dismutase was increased (p < 0.01) compared with the control. In conclusion, quails fed a diet containing 24% or 26% CP or diets supplemented with Mar or Thy oils or both exhibited improvement in the performance, lipid profile, immunity and antioxidant capacity without any detrimental impacts on the other studied parameters. 相似文献
127.
Rajwali Khan Hongfang Guo Sayed Haidar Abbas Raza Abdur Rahman Muhammad Ayaz Zan Linsen 《Tropical animal health and production》2018,50(8):1733-1738
Pre-slaughter and slaughter stressors are considered major concerns in animal welfare. Halal slaughtering method is considered one of the slaughtering stressors in livestock. This method seems to cause fear followed by stress in animals mainly due to inhuman handling. In this review, empathy and animal welfare are discussed in light of Islamic sharia and has further linked with animal’s physiology and behavioral responses during slaughtering. Islam as a religion forbids slaughtering an animal in front of another animal as through optic, olfactory, and cochlear senses animals can perceive the stress state of conspecifics. This suggests and strengthens the hypothesis that animals being slaughtered in front of each other may produce stress in them. This argument further leads to a claim that animals can experience empathy of each other through olfaction of semiochemicals (stress pheromones) emitted from animals slaughtered in the stressful condition that can be detected by other animals in abattoirs. Hence, research is needed to find out these specific stress pheromones and legislation needs to be adopted in slaughterhouses to isolate the areas of butchery from slaughtering lines to ensure proper guidelines of Halal slaughtering in slaughterhouses. 相似文献
128.
Mohammed S. Uddin Sharif A. Mukul Mohammed Abu Sayed A. Khan Mohammed Alamgir Md. Y. Harun Mohammad S. Alam 《Small-Scale Forestry》2008,7(2):139-149
Globally, trade in agar-based products is growing rapidly due to their recent adoption as an ingredient in the cosmetics and
pharmaceuticals sector. In Bangladesh, people living in some north-eastern districts have been engaged in the production,
processing and trading of such products for several decades. These practices, which they consider as the lifeblood of their
existence, have been inherited from their ancestors. This paper reports a case study carried out in Maulvibazar district exploring
the production and marketing, and industry problems, of agar-based enterprises and their potential contribution to socio-economic
development. An exploratory survey was undertaken over 30 randomly selected agar-based factories during December 2005–April
2006, with entrepreneurs of the factories personally interviewed using a semi-structured questionnaire. The majority of the
factories of the area were found to depend on local sources of raw materials to produce agar-based products. About 514 full
and part-time workers are employed in the factories. Average annual expenditure, revenue and net annual income per factory
for three consecutive years 2003–2005 of the study were estimated as Tk 63,980, Tk 111,414 and Tk 47,435, respectively, being
highest where attar (agar oil) of superior grade was produced for export. There appears to be a sustainable source of raw materials, availability
of technical and financial assistance and opportunity for expansion of market facilities to secure the maximum benefit achievable
from this highly promising industry.
相似文献
Sharif A. MukulEmail: |
129.
Mohamed R. Akl Nehad M. Ayoub Hassan Y. Ebrahim Mohamed M. Mohyeldin Khaled Y. Orabi Ahmed I. Foudah Khalid A. El Sayed 《Marine drugs》2015,13(1):288-311
Receptor tyrosine kinases are key regulators of cellular growth and proliferation. Dysregulations of receptor tyrosine kinases in cancer cells may promote tumorigenesis by multiple mechanisms including enhanced cell survival and inhibition of cell death. Araguspongines represent a group of macrocyclic oxaquinolizidine alkaloids isolated from the marine sponge Xestospongia species. This study evaluated the anticancer activity of the known oxaquinolizidine alkaloids araguspongines A, C, K and L, and xestospongin B against breast cancer cells. Araguspongine C inhibited the proliferation of multiple breast cancer cell lines in vitro in a dose-dependent manner. Interestingly, araguspongine C-induced autophagic cell death in HER2-overexpressing BT-474 breast cancer cells was characterized by vacuole formation and upregulation of autophagy markers including LC3A/B, Atg3, Atg7, and Atg16L. Araguspongine C-induced autophagy was associated with suppression of c-Met and HER2 receptor tyrosine kinase activation. Further in-silico docking studies and cell-free Z-LYTE assays indicated the potential of direct interaction between araguspongine C and the receptor tyrosine kinases c-Met and HER2 at their kinase domains. Remarkably, araguspongine C treatment resulted in the suppression of PI3K/Akt/mTOR signaling cascade in breast cancer cells undergoing autophagy. Induction of autophagic death in BT-474 cells was also associated with decreased levels of inositol 1,4,5-trisphosphate receptor upon treatment with effective concentration of araguspongine C. In conclusion, results of this study are the first to reveal the potential of araguspongine C as an inhibitor to receptor tyrosine kinases resulting in the induction of autophagic cell death in breast cancer cells. 相似文献
130.
Yongchao Zhang Yun-Kai Zhang Yi-Jun Wang Saurabh G. Vispute Sandeep Jain Yangmin Chen Jessalyn Li Diaa T. A. Youssef Khalid A. El Sayed Zhe-Sheng Chen 《Marine drugs》2015,13(4):2267-2286
Our previous studies showed that several sipholane triterpenes, sipholenol A, sipholenone E, sipholenol L and siphonellinol D, have potent reversal effect for multidrug resistance (MDR) in cancer cells that overexpressed P-glycoprotein (P-gp/ABCB1). Through comparison of cytotoxicity towards sensitive and multi-drug resistant cell lines, we identified that the semisynthetic esters sipholenol A-4-O-acetate and sipholenol A-4-O-isonicotinate potently reversed P-gp-mediated MDR but had no effect on MRP1/ABCC1 and BCRP/ABCG2-mediated MDR. The results from [3H]-paclitaxel accumulation and efflux studies suggested that these two triterpenoids were able to increase the intracellular accumulation of paclitaxel by inhibiting its active efflux. In addition, western blot analysis revealed that these two compounds did not alter the expression levels of P-gp when treated up to 72 h. These sipholenol derivatives also stimulated the ATPase activity of P-gp membranes, which suggested that they might be substrates of P-gp. Moreover, in silico molecular docking studies revealed the virtual binding modes of these two compounds into human homology model of P-gp. In conclusion, sipholenol A-4-O-acetate and sipholenol A-4-O-isonicotinate efficiently inhibit the P-gp and may represent potential reversal agents for the treatment of multidrug resistant cancers. 相似文献