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61.
62.
Summary ExpressingE. coli inorganic pyrophosphatase in transgenic plants demonstrated that long distance sucrose transport is dependent on cytosolic
pyrophosphate. It was speculated that removal of cytosolic pyrophosphate would impair sucrose utilization during storage of
potato tubers and thereby prevent tuber sprouting. To explore this hypothesisSolanum tuberosum var. Désirée plants were transformed with a chimeric PPa gene. FollowingAgrobacterium mediated transformation, metabolite and carbohydrate contents of growing and stored tubers were measured. There was a large
accumulation of soluble sugars and a decrease of starch at all developmental stages investigated. The PPase activity in PPaII
tubers was parallel with a decrease of PPa, an increase of fructose-2,6-bisphosphate and an increase of UDP-glucose. As expected
the amount of hexose-6-phosphates and glycolytic intermediates decreased. As a consequence PPaII tubers did not sprout even
after a prolonged storage period of two years. Since the energy status of PPaII tubers is unaltered inhibition of sprouting
is most likely due to reduced sucrose export and its subsequent utilization. 相似文献
63.
Annita Seok Kian Yong Wai Yee Mok Mohammad Lal Mohamad Tamrin Rossita Shapawi Yang‐Su Kim 《Aquaculture Research》2020,51(6):2252-2260
This trial was conducted to evaluate the effects of nucleotides on growth of whiteleg shrimp, Litopenaeus vannamei, and the survival and metabolic responses to ammonia stress test. Experimental diets were as follows: low fish meal diet (LFMD), and four LFMD test diets, each supplemented with 0.1% guanosine monophosphate (GMP), 0.1% inosine monophosphate (IMP), 0.1% mixture of GMP and IMP and 0.1% mixture of GMP, IMP, uridine monophosphate (UMP) and cytidine monophosphate (CMP). The shrimp specimens (initial body weight: 0.99 ± 0.01 g) were randomly allocated into five groups and fed four times daily for 8‐weeks. After the trial, final body weight was recorded and haemolymph was withdrawn for haematological analysis. The shrimp was then challenged with 70 mg/L ammonia (LC50) for 10 days. Survival and haemolymph of the shrimp were taken after exposure to ammonia. The highest growth performance was observed in the shrimp fed diet supplemented with GMP (p < .05), while survival was not influenced by the test diets in the feeding trial. In the ammonia challenge test, the highest survival was observed in the shrimp fed GMP supplemented diet compared to others. The plasma protein, glucose and cholesterol levels increased in all the treatments while triglycerides level decreased post challenge. Cortisol level recovered at day 10th after the challenge. Shrimps fed with nucleotides diets showed higher protein and glucose level compared to control groups post challenge. In general, nucleotides supplemented in the diet enhanced growth, improved stress resistance while modulating the haemolymph metabolites in L. vannamei under ammonia stress. 相似文献
64.
Yong Kit Chin Nurhidayu Al‐saari Zarirah Zulperi Aslizah Mohd‐Aris Annas Salleh Santha Silvaraj Aslah Mohamad JingYie Lee Mohd Zamri-Saad Md Yasin Ina-Salwany 《Aquaculture Research》2020,51(1):389-399
Vibrio harveyi causes vibriosis in various marine aquaculture fish species, especially when they are young. The infection subsequently leads to significant economic losses for aquaculture farms. Vaccination is recommended to control this disease. This study describes the efficacy of a live attenuated V. harveyi strain MVh_vhs (LAVh) as a vaccine candidate in controlling infection by wild‐type V. harveyi (WTVh) in Lates calcarifer. A total of 240 fingerlings were divided into four groups. Group 1 was not vaccinated and was not challenged, Group 2 was vaccinated with a formalin‐killed V. harveyi (FKVh), Group 3 was vaccinated with the LAVh before challenge and Group 4 was not vaccinated and was challenged. Bath vaccination was employed for one hour before the LAVh distribution was determined in the fish mucus, gill, liver, gut, kidney and spleen. The gills, livers, kidneys and skins were also sampled for gene expression analysis. To challenge the fish, skin abrasion was conducted before the fish were challenged by immersion with WTVh. The results revealed an extensive distribution of the LAVh in the liver and kidneys of the fish in Group 3 for the first 12 hr, resulting in mild lesions compared with Group 1. Similarly, there were significantly (p < .05) higher expressions of the Chemokine ligand 4 and major histocompatibility complex I genes in the skin and liver of the fish in Group 3 in comparison with other groups. Vaccination with LAVh resulted in a significantly high rate of survival (68%) of the fingerlings after being challenged with WTVh. 相似文献
65.
S. A. Sultan Al-Khalaf B. Taha Mohamad P. Nicoletti 《Tropical animal health and production》1992,24(1):45-49
Summary In Kuwait, approximately 12,000 diary cows were vaccinated with a reduced dose of 3×109
Brucella abortus strain 19 and approximately 350,000 sexually mature sheep and goats with a reduced dose of 107B.melitensis strain Rev. 1. Using the criteria of prevaccinal and postvaccinal incidences of antibodies, abortions, and human cases of
brucellosis, the programme was very successful. Widespread vaccination of adult animals is the most effective method of controlling
brucellosis among cattle, sheep and goats in many countries.
Resumen En Kuwait, se vacunaron aproximadament 12,000 vacas lecheras con una dosis reducida de 3×109 organismos deBrucella abortus cepa 19 y approximadament 350,000 ovejas y cabras sexualmente maduras fueron vacunadas con una dosis reducida de 107 organismos deB. melitensis opa Rev. 1. Utilizando los criterios prevacunales de incidencia de anticuerpos, abortos, y casos humanos de brucelosis, el programa fuvo gran exito. Ef método mas efectivo de control de la brucelosis bovina, ovina y caprina an numerosas paises es la amplia utilización de vacuna en animales adultos.
Résumé Au Kuwait, environ 12,000 vaches laitiěres ont été vaccinées avec une dose réduite de souche 19Brucella abortus (3×109) et environ 350,000 moutons et chevres qui étaient matures sexuellement, one été vaccinés avec une dose réduite de soucheB. melitensis Rev. 1 (107). Basé sur la présence d'anticorps, sur le nombre d'avortements et de cas de brucellose chez les humains avant et aprés vaccination, le programme a été un succěs. La méthode la plus effective pour contr?ler la brucellose chez les bovins, les ovins et les caprins dans beaucoup de pays et de vacciner sans exception tous les animaux adultes.相似文献
66.
Abstract The germination of alang-alang rhizome buds was found to be affected by the colour of the buds, the length of the rhizome sections, and the orientation of the sections in the cultural medium. The position of the buds on the sections did not affect the germination of the buds, nor did the differences in diameter of the rhizomes. Subsequent growth of the buds was positively affected by increasing the lengths of the sections. 相似文献
67.
Mohammed Danish Rokiah Hashim M. N. Mohamad Ibrahim Othman Sulaiman 《Wood Science and Technology》2014,48(5):1069-1083
A study on the preparation of activated carbon from Acacia mangium wood was conducted, and the operating factors, such as activating agent concentration, activation temperature and activation time, were optimized using response surface methodology. In order to determine the effects of the operating factors namely H3PO4 concentration (6.48–48.5 %), activation temperature (364–1,036 °C) and activation time (19–146 min) on the characteristics of activated carbon, a three-level rotatable central composite design was used. The second-order mathematical model was proposed by regression analysis of the experimental data gathered from 20 batch runs. The optimum H3PO4 concentration, activation temperature and activation time were found to be 40 %, 900 °C and 45 min, respectively. At optimum conditions of the operating factors, the percent yield and surface area were 20.3 % and 1,767 m2/g, respectively. The activated carbon was found to be largely composed of mesopores. About 95 % of the total surface area was attributed to mesopores. 相似文献
68.
Moustafa Salouci Nadine Antoine Mohamad Khir Shikh Al Sook Joëlle Piret Yvan Mignon Nathalie Kirschvink Annick Gabriel 《Veterinary research communications》2014,38(4):279-285
Astroglial account for the largest glial population in the brain and play a variety of vital functions in the development of the central nervous system (CNS). An immunohistochemical study was performed in 19 ovine foetuses ranging from 2 to 5 months of gestation, one newborn lamb and three adult sheep. Using the anit-glial fibrillary acidic protein (GFAP) marker, several variations were found in the degree of GFAP positive (GFAP+) astrocyte distribution between the different zones in the cerebellum of sheep during brain development. Our study indicates that the first appearance of astrocytes from restricted zones in the cerebellum occurs around the eighth week of gestation. Bergmann cells were found to be present from around the 15th week of gestation onwards. Our findings suggest that the maturation of astrocytes begins in the caudal parts of the cerebellum, developing from their initial ventral regions to spread first to dorsal regions radially within the white matter, then followed by the more rostral parts of the cerebellum. Astrocytes were also found to proliferate in the vermis before appearing in the cerebellar hemispheres. 相似文献
69.
70.
Saeidi Z Vatandoost H Akhavan AA Yaghoobi-Ershadi MR Rassi Y Sheikh Z Arandian MH Jafari R Sanei Dehkordi AR 《Pest management science》2012,68(5):669-675
BACKGROUND: Phelebotumus papatsi is considered to be the main vector of zoonotic cutaneous leishmaniasis as well as sand fly fever in Iran. There are several measures for vector control, with emphasis on insecticides. The objective of this study was to determine the baseline susceptibility of this vector to the commonly used insecticides in an endemic focus of the disease in central Iran. P. papatasi collected from the field were used for susceptibility status. Its baseline susceptibility to DDT and pyrethroids was assessed on about 6866 specimens collected from Badrood rural district, Esfahan Province, Iran, during the summer of 2010. The LT50 and LT90 values were measured according to the World Health Organisation (WHO) test using probit analysis and regression lines. RESULTS: Results of tests against female P. papatasi revealed LT50 values to DDT 4%, permethrin 0.75%, deltamethrin 0.1%, cyfluthrin 0.15% and lambdacyhalothrin 0.05% of 1104.97, 182.35, 26.79, 15.42 and 1.48 s respectively. The figures for male P. papatasi were 973.51, 59.5, 4.4, 2.65 and 1.5. CONCLUSION: The results of this study provide a guideline for implementation of different vector control measures. Furthermore, guidelines are needed for monitoring and evaluation of insecticide susceptibility tests against sand flies. Copyright © 2012 Society of Chemical Industry 相似文献