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101.
K. Saïd T. Jacquart C. Montgelard H. Sonjaya A. N. Helal J. Britton-Davidian 《Genetica》1986,68(2):151-156
A new population of Mus musculus domesticus showing Robertsonian translocations (2n = 22) has been identified in Tunisia.
Mice carried 9 pairs of Robertsonian translocations: Rb(1.11), Rb(2.16), Rb(3.12), Rb(4.6), Rb(5.14), Rb(7.18), Rb(8.9), Rb(10.17)
and Rb(13.15). Five of the nine translocations are not known to occur elsewhere. In two populations only 2n = 22 mice were
present, whereas in a third one a mixture of karyotypes (2n = 22, 38, 39, 40) was found. The slight electrophoretic differentiation
observed for other Robertsonian populations as well as the hybrid nature of the karyotypically heterogeneous populations are
confirmed. Allele frequency differences between the 2n = 22 and 2n = 40 mice in the latter population show that local electrophoretic
differentiation exists and allow to compare chromosome flow and gene flow. The presence of a chromosome-1 polymorphism for
additional fragments of heterochromatin present in the Robertsoman population provides a convenient marker of recombinational
events in the hybrid zone. 相似文献
102.
The first gene assignment to a horse chromosome is reported for equine leucocyte antigen (ELA), the major histocompatibility complex of the horse. A cloned DNA sequence derived from a class I gene of the porcine major histocompatibility complex was used as a probe for an in situ hybridization experiment. We present the regional localization of ELA, using this sequence, to equine chromosome 20g14-q22. 相似文献
103.
Studies of esterase 6 in Drosophila melanogaster. XVIII. Biochemical differences between the slow and fast allozymes 总被引:1,自引:0,他引:1
Most natural populations of Drosophila melanogaster are polymorphic for two
major electrophoretic variants at the esterase-6 locus. The frequency of
the EST 6F allozyme is greatest in populations in warmer latitudes, whereas
the EST 6S allozyme is predominant in colder latitudes. Latitudinal clines
in electromorph frequencies are found on three continents. Purified
preparations of the allozymes have been characterized for their pH optimum,
substrate specificity, organophosphate inhibition, alcohol activation,
thermal stability, and kinetic parameters. These and previous analyses of
the EST 6 allozymes reveal that the two variants have differences in their
physical and kinetic properties that may provide a basis for the selective
maintenance of the polymorphisms and an explanation of the clinal variation
observed in natural populations.
相似文献
104.
Khalid Eljaaly Asalah Helal Tamather Almandeel Rawan Algarni Samah Alshehri 《Saudi Journal of Biological Sciences》2021,28(12):6929-6932
IntroductionOral fluoroquinolones and tetracyclines are known to interact with divalent or trivalent cation-containing compounds (DTCCs) via chelation. The objective of this study is to describe the prevalence of these drug-drug interactions (DDIs) in an inpatient setting.MethodsA cross-sectional study of prospectively collected data were conducted at an academic tertiary care hospital. We included hospitalized adults who were receiving oral fluoroquinolones or tetracyclines with DTCCs in 2019. Our hospital uses electronic health records for medication ordering and handwritten medication administration records (MARs). The primary study outcome was the percentage of simultaneous administration of fluoroquinolones or tetracyclines with DTCCs, and the secondary outcome was the percentage of inappropriate separation time.ResultsAmong patients who received oral fluoroquinolones or tetracyclines, 47 patients (26.6%) were co-administered DTCCs and included in this study. Ciprofloxacin (n = 29; 61.7%) was the most commonly interacting antibiotic, followed by moxifloxacin (n = 12; 25.5%) and doxycycline (n = 6; 12.8%). The interacting DTCCs included iron-containing products and calcium-containing products, and half of the patients (n = 24; 51%) received DTCCs once daily. Most patients (n = 35; 74.5%) were found to receive oral fluoroquinolones or tetracyclines at the same time as DTCCs, while one (2.1%) received inappropriately separated DTCCs.ConclusionsDespite being a very known contraindicated DDI, the prevalence of simultaneous co-administration of oral fluoroquinolones or tetracyclines with polyvalent cations was extremely high in a hospital with handwritten MARs. Antimicrobial stewardship programs should target this DDI, and future studies should evaluate the impact of different practical solutions to this problem in different clinical settings. 相似文献
105.
Racha Helal Matthias F. Melzig 《In vitro cellular & developmental biology. Animal》2010,46(6):492-496
The main purpose of this study was to investigate lysozyme synthesis and secretion in three human monocyte cell lines: U-937,
HL-60, and THP-1, using sensitive fluorescence-based assay of lysozyme activity. PMA and hIFN-γ were evaluated for inducing
lysozyme activity. Using well-defined cell lines from the cell culture collection, no lysozyme activity could be detected
in the cultured U-937 cells either with or without addition of the inducing factors. These data suggested, contrary to previous
reports, that U-937 cell line cannot synthesize or secrete active lysozyme. THP-1 and HL-60 cells were proved to produce enzymatically
active lysozyme in increasing amounts with the time course. PMA and hIFN-γ had no significant inducing effect on the production
or the release of active lysozyme in THP-1 and HL-60 cells. We showed inhibiting effect of PMA and hIFN-γ on the lysozyme
activity, particularly in HL-60 cell line. 相似文献
106.
107.
Plasmodium falciparum calcium-ATPase (PfATP6) has been reported to be a target of artemisinin and related endoperoxides. In this study, a series of previously reported guaianolide-endoperoxides (thaperoxides) were docked into a homology model of PfATP6 and also used to develop a pharmacophore model. This combined approach led to useful insights into the binding determinants of thaperoxides to the malarial enzyme. In addition, in silico mutagenesis and molecular dynamics suggested the importance of Phe264 and the electrostatic interactions between Lys260 in helix H3 and Lys1036 and Asp1038 in L6/7 loop for the binding of thaperoxides. These results could help in the design of more potent inhibitors of PfATP6. 相似文献
108.
A new fluorogenic substrate 1, which enables the fast and quantitative analysis of alkaline phosphatase activity, has been developed. Selective enzymatic hydrolysis of 1 instantly generated fluorescent compound 2 in aqueous media, which undergo an excited-state intramolecular proton transfer process, resulting in a remarkable fluorescence turn-on signal with an unusually large Stokes shift. 相似文献
109.
110.
Mirjafari H Farragher TM Verstappen SM Yates A Bunn D Marshall T Lunt M Symmons DP Bruce IN 《Arthritis research & therapy》2011,13(5):R159