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排序方式: 共有885条查询结果,搜索用时 15 毫秒
881.
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883.
Antimicrobial and antispasmodic activity of leaf extract and fractions of Stachytarpheta cayennensis
TC Okoye PA Akah CO Okoli AC Ezike FN Mbaoji 《Asian Pacific journal of tropical medicine》2010,3(3):189-192
ObjectiveTo investigate the antimicrobial activity of the methanol leaf extract (ME), n-hexane fraction (HF), ethylacetate fraction (EF) and methanol fraction (MF), of Stachytarpheta cayennensis C. Rich (verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions (HF, EF and MF) on acetylcholine (Ach) and histamine (H) induced contractions on isolated guinea pig ileum.MethodsThe in vitro agar well diffusion method was used for the antimicrobial studies while the isolated tissue method was employed for the antispasmodic test. Organisms used were all clinical isolates of Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella paratyphi, Candida albicans and Aspergillus niger.ResultsThe extract and fractions exhibited dose dependent inhibition against all the bacteria tested and also exhibited insignificant antifungal activity against Candida albicans and Aspergillus niger. The minimum inhibitory concentration (MIC) of the extract and fractions (mg/mL) on Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella paratyphi respectively were ME 5.62, 14.12, 22.38, 2.11; EF 1.25, 6.30, 9.40, 9.40 and MF 3.98, 8.81, 39.80, 21.13. The n-hexane fraction exhibited MIC of 1.07 mg/mL against only Bacillus subtilis. The extract and fractions exhibited significant (P< 0.05) dose dependent attenuation of contractions induced by acetylcholine and histamine on isolated guinea pig ileum. Concentrations of the extract and fractions (μg/mL) which evoked 50% inhibition of maximal response exhibited by Ach were ME 0.64, HF 0.16, EF 0.08 and MF 0.15, while that of histamine included ME 5.12, HF 0.16, EF 0.04 and MF 0.64. Preliminary phytochemical studies on the extract and fractions indicated the presence of carbohydrates, alkaloids, saponins, flavonoids, steroids and terpenoids.ConclusionsThe extract and fractions of Stachytarpheta cayennensis possessed both antibacterial and antispasmodic effects confirming the claimed use in folkloric medicine for wound healing and gastrointestinal ulceration. 相似文献
884.
A stable, nonsense mutation associated with a case of infantile onset polycystic kidney disease 1 (PKD1) 总被引:8,自引:0,他引:8
Peral B; Ong AC; San Millan JL; Gamble V; Rees L; Harris PC 《Human molecular genetics》1996,5(4):539-542
Autosomal dominant polycystic kidney disease (ADPKD) is the most common
single gene disorder resulting in renal failure. It is generally an adult
onset disease, but rarely, cases of severe childhood polycystic disease
arise in ADPKD families. The clear clinical anticipation in these pedigrees
has led to the suggestion that the mutation may be an unstable
trinucleotide repeat. We have now identified a nonsense mutation,
Tyr3818Stop, in one such family (P117) within the major ADPKD gene,
polycystic kidney disease 1 (PKD1). The mutation is shown to be a de novo
change in the father, and of grandpaternal origin. PKD1 manifests as
typical adult onset disease in the father, but is seen as severe disease,
detected as enlarged polycystic kidneys in utero, in one of a pair of
dizygotic twins; the other twin has the mutation but no evidence of cysts,
consistent with an adult onset disease course. The finding of the same
stable mutation associated with very different disease severity in this
family indicates that phenotypic variation in PKD1 is not due to a dynamic
mutation. It seems most likely that a small number of modifying factors may
radically affect the course of disease in PKD1; identification of such
factors will have important prognostic implications in this disorder.
相似文献
885.
Saskia Lassche Anke Rietveld Arend Heerschap Hieronymus W van Hees Maria TE Hopman Nicol C Voermans Christiaan GJ Saris Baziel GM van Engelen Coen AC Ottenheijm 《Neuromuscular disorders : NMD》2019,29(6):468-476
Atrophy and fatty infiltration are important causes of muscle weakness in inclusion body myositis (IBM). Muscle weakness can also be caused by reduced specific force; i.e. the amount of force generated per unit of residual muscle tissue. This study investigates in vivo specific force of the quadriceps and ex vivo specific force of single muscle fibers in patients with IBM. We included 8 participants with IBM and 12 healthy controls, who all underwent quantitative muscle testing, quantitative MRI of the quadriceps and paired muscle biopsies of the quadriceps and tibialis anterior. Single muscle fibers were isolated to measure muscle fiber specific force and contractile properties. Both in vivo quadriceps specific force and ex vivo muscle fiber specific force were reduced. Muscle fiber dysfunction was accompanied by reduced active stiffness, which reflects a decrease in the number of attached actin-myosin cross-bridges during activation. Myosin concentration was reduced in IBM fibers. Because reduced specific force contributes to muscle weakness in patients with IBM, therapeutic strategies that augment muscle fiber strength may provide benefit to patients with IBM. 相似文献