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排序方式: 共有336条查询结果,搜索用时 718 毫秒
1.
The aim of this investigation was to evaluate the semen quality traits of purebred male rabbits and their crosses under subtropical Egyptian conditions. A full 3 x 3 diallel crossing was performed for producing the first generation progeny of New Zealand White (N), Flander (F) and Rex (R) breeds. The highest ejaculate volume (p< 0.05) and percentage of live sperms (p<0.01) with the lowest percentage of sperm cell morphological abnormalities (p<0.05) had been recorded in the NF bucks. Moreover, they possessed positive estimates of direct heterosis for ejaculate volume, mass motility (Mm), individual motility (Im) and sperm cell concentration (SCC). On the contrary, pH had negative estimates of direct heterosis in all crosses and their reciprocal. Semen pH was negatively correlated with SCC (r = -0.18), Mm (r = -0.13) and Im (r = -0.23). In conclusion, the superiority of crossbreeding was particularly obvious in the New Zealand White x Flander males, which cumulated heterosis and favorable maternal effects of the Flander dams. 相似文献
2.
The effect of NAD(P) and analogs of this nucleotide on nitrogenase activity in Rhodospirillum rubrum has been studied. Addition of NAD+ to nitrogen fixing Rsp. rubrum leads to inhibition of nitrogenase. NADP+ has the same effect but NADH or analogs modified in the nicotinamide portion do not cause inhibition. In contrast to ammonium
ions, addition of NAD+ leads to inhibition of nitrogenase in cells that have been N-starved under argon. The inhibitory effect of NAD+ is more pronounced at lower light intensities. Addition of NAD+ also leads to inhibition of glutamine synthetase, a phenomenon also occurring when “switchoff” is produced by the addition
of effectors such as ammonium ions or glutamine. It is also shown that NAD+ is taken up by Rsp. rubrum cells. 相似文献
3.
Ginette Pauly Abdelhamid Yani Louis Piovetti Colette Bernard-Dagan 《Phytochemistry》1983,22(4):957-959
The essential oils of the leaves of Cupressus dupreziana and Cupressus sempervirens were compared. The composition of the hydrocarbon fraction showed a great similarity between the two species. 相似文献
4.
Youssef Dalia El-Bakatoushi Ranya Elframawy Asmaa El-Sadek Laila Badan Ghada El 《Journal of plant research》2023,136(3):305-322
Journal of Plant Research - The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of... 相似文献
5.
Khaoula Rochdi Cerino Mathieu Da Silva Nathalie Delague Valerie Nahili Halima Kriouile Yamna Gorokhova Svetlana Bartoli Marc Saïle Rachid Barakat Abdelhamid Krahn Martin 《Molecular biology reports》2021,48(10):6999-7006
Molecular Biology Reports - Congenital myasthenic syndromes (CMS) are associated with defects in the structure and the function of neuromuscular junctions. These rare disorders can result from... 相似文献
6.
Mariem Khouja Rita C. Alves Diana Melo Anabela S. G. Costa M. Antonia Nunes Abdelhamid Khaldi M. Beatriz P. P. Oliveira Chokri Messaoud 《化学与生物多样性》2021,18(6):e2100071
The lipid fraction of seeds from different pine species and populations was studied regarding total lipid content, fatty acid profile and vitamin E composition. The investigated seeds contained a high percentage of lipid (13.6 to 31.5 %). Lipid fractions were found to be rich in vitamin E, which varied significantly among species and populations. P. halepensis (Ph−Hn) showed the highest content of vitamin E (256.3 mg/kg of seeds) and the uppermost content of α-tocopherol (44 mg/kg). However, P. halepensis (Ph−Kas) was the richest in γ-tocopherol (204.9 mg/kg). Lipid fractions had a low content of δ-tocopherol (1.2 to 3.6 mg/kg. The highest content of γ-tocotrienol (∼18 %) was determined for P. halepensis (Ph−Dc and Ph−Hn). Thirteen fatty acids were identified by GC-FID with significant variation between the investigated species. The linoleic acid was the major fatty acid followed by oleic acid and palmitic acid. The chemical differentiation among species for the composition of fatty acids and vitamin E was confirmed by PCA. Significant correlations were observed between the content of vitamin E and fatty acids and ecological parameters of P. halepensis populations. 相似文献
7.
Ghada Farouk El-Said 《人类与生态风险评估》2013,19(5):1285-1305
This study examined the bioaccumulation of key metals and other contaminants (SO4, F, Na, K, Ca, Mg, P, Si, Fe, Mn, Zn, Ni, Co, Cu, and Cd) by seaweeds from the Egyptian Mediterranean Sea coast and their risk to human health. Bioaccumulation factor calculations indicated that S, F, Na, K, Zn, Cu, and Cd had high seaweed uptake and this referred to the potential pollution of the coastal area. Multivariate analysis of the studied contaminants confirmed the bioaccumulation factor results as well as the physiological processes in seaweeds. Human health risk assessment of F, Mn, Zn, Ni, Cu, and Cd was conducted using hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) analyses. The carcinogenic assessment of sediments and ingestion of seaweeds using ILCR calculations revealed that Mn, Ni, and Cd in sediments and F and Zn in seaweeds require remedial action in order to reduce their human health risks. Additionally, HQ calculations for the contaminants in seaweeds and reference to toxicological references values from different agencies revealed that F and Co present high human health risk effects. Consequently, the potential public health risks from dietary exposure to hazardous contaminants in seaweeds must be continually subjected to research, regulation, and debate. 相似文献
8.
Ghada S Hassan Daniel Yacoub Nada Alaaeddine Amal Nadiri Yahye Merhi Walid Mourad 《Arthritis research & therapy》2013,15(1):206
Atherosclerosis, now regarded as a chronic inflammatory disease of the arterial wall, and its clinical manifestations have increasingly been associated with rheumatoid arthritis (RA), supporting the notion that autoimmune diseases and vascular disorders share common etiological features. Indeed, evidence pertaining to this matter indicates that inflammation and its multiple components are the driving force behind the pathogenesis of these disorders. Interestingly, CD154 and its receptors have emerged as major players in the development of RA and atherosclerosis, which raises the possibility that this axis may represent an important biological link between both complications. Indeed, CD154 signaling elicits critical inflammatory responses that are common to the pathogenesis of both diseases. Here, we provide an overview of the traditional and disease-related interrelations between RA and vascular abnormalities, while focusing on CD154 as a potential mediator in the development of atherosclerotic events in RA patients. 相似文献
9.
Lawren VandeVrede Ramy Abdelhamid Zhihui Qin Jaewoo Choi Sujeewa Piyankarage Jia Luo John Larson Brian M. Bennett Gregory R. J. Thatcher 《PloS one》2013,8(8)
Selective estrogen receptor modulators (SERMs) are effective therapeutics that preserve favorable actions of estrogens on bone and act as antiestrogens in breast tissue, decreasing the risk of vertebral fractures and breast cancer, but their potential in neuroprotective and procognitive therapy is limited by: 1) an increased lifetime risk of thrombotic events; and 2) an attenuated response to estrogens with age, sometimes linked to endothelial nitric oxide synthase (eNOS) dysfunction. Herein, three 3rd generation SERMs with similar high affinity for estrogen receptors (ERα, ERβ) were studied: desmethylarzoxifene (DMA), FDMA, and a novel NO-donating SERM (NO-DMA). Neuroprotection was studied in primary rat neurons exposed to oxygen glucose deprivation; reversal of cholinergic cognitive deficit was studied in mice in a behavioral model of memory; long term potentiation (LTP), underlying cognition, was measured in hippocampal slices from older 3×Tg Alzheimer''s transgenic mice; vasodilation was measured in rat aortic strips; and anticoagulant activity was compared. Pharmacologic blockade of GPR30 and NOS; denudation of endothelium; measurement of NO; and genetic knockout of eNOS were used to probe mechanism. Comparison of the three chemical probes indicates key roles for GPR30 and eNOS in mediating therapeutic activity. Procognitive, vasodilator and anticoagulant activities of DMA were found to be eNOS dependent, while neuroprotection and restoration of LTP were both shown to be dependent upon GPR30, a G-protein coupled receptor mediating estrogenic function. Finally, the observation that an NO-SERM shows enhanced vasodilation and anticoagulant activity, while retaining the positive attributes of SERMs even in the presence of NOS dysfunction, indicates a potential therapeutic approach without the increased risk of thrombotic events. 相似文献
10.
Majida Charif Amina Bakhchane Omar Abidi Redouane Boulouiz Abdelmajid Eloualid Rachida Roky Hassan Rouba Mostafa Kandil Guy Lenaers Abdelhamid Barakat 《Gene》2013
Mutations in the CLDN14 gene, encoding the tight junction claudin 14 protein has been reported to date in an autosomal recessive form of isolated hearing loss DFNB29. In order to identify the contribution of CLDN14 to inherited deafness in Moroccan population, we performed a genetic analysis of this gene in 80 Moroccan familial cases. Our results show the presence of 7 mutations: 6 being conservative and one leading to a missense mutation (C11T) which was found at heterozygous and homozygous states, with a general frequency of 6.87%. The pathogenicity of the resulting T4M substitution is under discussion. 相似文献