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961.
Siddig A. Rahoud Adil Mergani Ammar H. Khamis Osman K. Saeed Qurashi Mohamed-Ali Alain J. Dessein & Nasr Eldin M.A. Elwali 《FEMS immunology and medical microbiology》2010,58(1):106-112
An association study of a cohort of 177 Sudanese patients infected with Schistosoma mansoni [82 (46%) males and 95 (54%) females] was conducted to evaluate the factors controlling the regression of liver fibrosis 39 months after treatment with praziquantel using ultrasound evaluation. Periportal fibrosis (PPF) was regressed in 63 (35.6%) patients, while the disease progressed to higher grades in 24 (13.6%) patients. The grade of PPF did not change in 90 (50.8%) patients. The mean values of portal vein diameter, splenic vein diameter and index liver size in subjects in whom PPF regressed after treatment were significantly lower than in subjects in whom the disease was progressed ( P <0.0001, P =0.031 and P =0.003, respectively). The progression of hepatic fibrosis in males (15, 8.5%) was greater than that in females (9, 5.1%). Patients with regression or progression phenotypes tend to cluster in certain families. Our study indicated that regression, progression and stabilization of PPF after praziquantel therapy is controlled by gender, age, grade of fibrosis and possibly inherited factors. 相似文献
962.
Cemal Sandalli Sabriye Canakci İsmail Demir Mukund J. Modak Ali Osman Belduz 《World journal of microbiology & biotechnology》2010,26(3):459-464
DNA polymerases are used for many applications and we comparatively investigated DNA synthesis activity of DNA polymerase I enzymes of Geobacillus caldoxylosilyticus TK4, Escherichia coli and Mycobacterium tuberculosis with DIG-11-dUTP using synthetic DNA substrates. We showed that Gca polymerase I and Klenow Fragment (KF) used DIG-11-dUTP instead of dTTP almost at the same ratio, but more efficiently than Mtb polymerase I. We considered that Gca polymerase I could be efficiently used to label a DNA oligonucleotide either internally or at the 3′-terminus by DIG-11-dUTP for the generation of non-radioactive labeled DNA substrates at higher temperature than KF. All three polymerases could not elongate the primer terminus after adding ddNTPs into DNA that is characteristic for all known DNA polymerase I enzymes. 相似文献
963.
Kristin Odlo Jérémie Fournier-Dit-Chabert Sylvie Ducki Osman A.B.S.M. Gani Ingebrigt Sylte Trond Vidar Hansen 《Bioorganic & medicinal chemistry》2010,18(18):6874-6885
A series of cis-restricted 1,4- and 1,5-disubstituted 1,2,3-triazole analogs of combretastatin A-4 (1) have been prepared. Cytotoxicity and tubulin inhibition studies showed that 2-methoxy-5-((5-(3,4,5-trimethoxyphenyl)-1H-1,2,3-triazol-1-yl)methyl)aniline (5e) and 2-methoxy-5-(1-(3,4,5-trimethoxybenzyl)-1H-1,2,3-triazol-5-yl)aniline (6e) were two of the most active compounds. Molecular modeling studies revealed that the N-2 and N-3 atoms in the triazole rings in 5e and 6e did not form hydrogen bonds with the amino acids in the anticipated pharmacophore. 相似文献
964.
Faizel Osman Suman Kundu Jiun Tuan Mohamed Jeilan Peter J Stafford G Andre Ng 《Indian pacing and electrophysiology journal》2010,10(2):104-107
Catheter ablation is increasingly used to treat patients with atrial fibrillation (AF). Ablation of ganglionic plexi is often performed to reduce vagal innervation and has been shown to confer a better long-term outcome in terms of AF recurrence. We report a case of a patient having AF ablation with a profound vagal response, suggesting ganglionic plexus ablation, who subsequently developed ventricular fibrillation after programmed ventricular stimulation. Reduced vagal modulation is known to predispose to ventricular arrhythmias and vagal denervation following AF ablation may predispose to ventricular arrhythmias and requires further study. 相似文献
965.
Cation-coupled active transport is an essential cellular process found ubiquitously in all living organisms. Here, we present two novel ligand-free X-ray structures of the lactose permease (LacY) of Escherichia coli determined at acidic and neutral pH, and propose a model for the mechanism of coupling between lactose and H+ translocation. No sugar-binding site is observed in the absence of ligand, and deprotonation of the key residue Glu269 is associated with ligand binding. Thus, substrate induces formation of the sugar-binding site, as well as the initial step in H+ transduction. 相似文献
966.
Nurhan Gumral Mustafa Naziroglu Ahmet Koyu Kurtulus Ongel Omer Celik Mustafa Saygin Mesud Kahriman Sadettin Caliskan Mustafa Kayan Osman Gencel Manuel F. Flores-Arce 《Biological trace element research》2009,132(1-3):153-163
The levels of blood lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamin C were used to follow the level of oxidative damage caused by 2.45 GHz electromagnetic radiation in rats. The possible protective effects of selenium and L-carnitine were also tested and compared to untreated controls. Thirty male Wistar Albino rats were equally divided into five groups, namely Groups A1 and A2: controls and sham controls, respectively; Group B: EMR; Group C: EMR + selenium, Group D: EMR + L-carnitine. Groups B–D were exposed to 2.45 GHz electromagnetic radiation during 60 min/day for 28 days. The lipid peroxidation levels in plasma and erythrocytes were significantly higher in group B than in groups A1 and A2 (p?<?0.05), although the reduced glutathione and glutathione peroxidase values were slightly lower in erythrocytes of group B compared to groups A1 and A2. The plasma lipid peroxidation level in group A2 was significantly lower than in group B (p?<?0.05). Erythrocyte reduced glutathione levels (p?<?0.01) in group B; erythrocyte glutathione peroxidase activity in group A2 (p?<?0.05), group B (p?<?0.001), and group C (p?<?0.05) were found to be lower than in group D. In conclusion, 2.45 GHz electromagnetic radiation caused oxidative stress in blood of rat. L-carnitine seems to have protective effects on the 2.45-GHz-induced blood toxicity by inhibiting free radical supporting antioxidant redox system although selenium has no effect on the investigated values. 相似文献
967.
Osman Erol Mine Kocyigit Levent Şik Neriman Özhatay Orhan Kucuker 《Nordic Journal of Botany》2010,28(2):186-188
A new subspecies Crocus antalyensis subsp. striatus subsp. nov. from western Turkey is described. It is characterized by rough papery, light brown corm tunics, leaves that exceed the flower at anthesis and are recurved, distinctly striped inner perianth segments and deeply branched pale yellow or white style. The karyotype of the new subspecies is presented. 相似文献
968.
969.
Gyrgy Cska Anik Hirka Serap Mutun Milka Glavendeki gnes Mik Levente Szcs Mrton Paulin Csaba Bla Etvs Csaba Gspr Mariann Csepelnyi gnes Sznsi Milivoj Franjevi Yuri Gninenko Mirza Dautbai Osman Muzejinovi Milan Zúbrik Constantin Netoiu Andrei Buzatu Flavius Blcenoiu Maja Jurc Duan Jurc Iris Bernardinelli Jean‐Claude Streito Dimitrios Avtzis Boris Hraovec 《Agricultural and Forest Entomology》2020,22(1):61-74
- The North American oak lace bug feeds on leaves of ‘white oaks” in its native range. In Europe, it was first discovered in northern Italy in 2000. In recent years, it has subsequently spread rapidly and population outbreaks have been observed in several European countries. In the present study, we summarize the steps of its expansion.
- To predict its potential host range, we checked 48 oak species in 20 sentinel gardens in seven countries between 2013 and 2018.
- In total, 27 oak species were recorded as suitable hosts; 13 of them are globally new ones, 23 out of the 29 in section Quercus (~ white oaks, an intrageneric taxonomic unit within genus Quercus), including Asian oaks, native to Japan, Korea and China, and four out of five in section Cerris (another intrageneric unit of the same genus), were accepted as hosts. None of the species in section Lobatae (red oaks) or in the Ilex group was accepted.
- Host records were also collected in forest stands of 10 countries. We found 11 oak species that were infested. Outbreak populations were most commonly found on Quercus robur, Quercus frainetto, Quercus petraea and Quercus cerris, comprising widespread and outstandingly important oaks species in Europe.
- Based on our findings, we conclude that suitable hosts for oak lace bug are present in most of Europe and Asia. This means that a lack of hosts will likely not restrict further range expansion.