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91.
Two double-stranded RNA (dsRNA) segments of a virus with a bipartite genome identified in fig (Ficus carica L.) and denoted Fig cryptic virus (FCV) were cloned and sequenced. Viral dsRNAs are 1696 bp (RNA-1) and 1415 bp (RNA-2) in size. RNA-1 contains a single ORF (1419 nt) potentially encoding a 54 kDa protein and comprising the conserved amino acid motifs of the RNA-dependent RNA polymerase (RdRp) domain of species of the genus Alphacryptovirus. Its full-length amino acid sequence has the highest identity with Raphanus sativus cryptic virus 2 (RsCV-2) (36%), Beet cryptic virus 3 (BCV-3) (36%) and Fragaria chiloensis cryptic virus (FCCV) (34%). RNA-2 has also a single ORF (1014 nt) coding for a polypeptide with a predicted molecular mass of 38 kDa, identified as the viral coat protein (CP). In a phylogenetic tree constructed with the amino acid sequences of the RdRp domain, FCV clusters in a clade comprising BCV-3 and a number of tentative species of the genus Alphacryptovirus. FCV is not mechanically transmissible. It was detected in fig orchards of six Mediterranean countries (Albania, Algeria, Italy, Lebanon, Syria and Tunisia) where it does not seem to induce a visible disease.  相似文献   
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During the invasive phase of malignant tumors, neoplastic cells break into the basal lamina and enter in contact with the underlying connective tissue, which concurrently undergoes extensive modifications. The aim of our present minireview is to focus the changes in the collagenous matrix occurring during breast cancer progression and to explore the possible effects of different collagen substrates on breast cancer cell behavior and proteomic modulation.  相似文献   
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Sir, The calcimimetic drug cinacalcet, recently introduced as therapyfor Secondary Hyper-Parathyrodism (SHP) in dialysis patients,has greatly enhanced the ability to achieve simultaneous controlof parathyroid hormone (PTH), calcium and phosphate [1]. However, there have been no data to show that a better controlof mineral metabolic parameters is matched with improved clinicaloutcomes of vascular calcification processes, and hence, ofvascular morbidity and mortality. Recent studies have shown that both osteoprotegerin (OPG) andFetuin-A are associated with the vascular calcification process  相似文献   
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Acute leukaemias are characterized by non-random chromosomal aberrations which are often strictly related to the inactivation of tumour suppressor genes (TSGs). Alterations at the short arm of chromosome 9 have been reported in a remarkable percentage of acute lymphoblastic leukaemias (ALL) and have been suggested to cause the loss of activity of the putative TSG, p16INK4A (MTS1/CDKN2) gene. In order to evaluate the correlation between this gene inactivation and visible cytogenetic abnormalities, we have investigated p16INK4A homozygous gene deletions in 10 paediatric acute leukaemias of different cell lineages which demonstrated karyotype aberrations involving chromosome 9. Moreover, the dimension of the genetic alteration was evaluated by studying the loss of heterozygosity of two highly polymorphic markers of chromosome 9p, namely α-interferon (IFNA) and D9S104, and the deletion of 5'-methylthioadenosine phosphorylase (MTAPase) gene. Finally, the deletion of a gene belonging to p16INK4A family, the p18 gene, was analysed in these acute leukaemias. Our results demonstrated that: (i) the biallelic loss of p16INK4A gene is strictly related to a specific immunophenotype, namely ALL of T-cell lineage; (ii) no significant correlation exists between alterations at chromosome 9p level and the homozygous deletions of p16INK4A gene; and (iii) p18 gene was not deleted in the examined cases. These findings suggest a possible correlation between the T-lymphocyte phenotype and the expression of p16INK4A gene. Moreover, the absence of MTAPase activity seems to be a valuable marker of p16INK4A gene inactivation, thus indicating that the deleted chromosomal area on 9p21 very frequently involves the MTAPase gene.  相似文献   
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This report describes the usefulness of transesophageal atrial pacing in the treatment of five patients with hyperkalemia-induced bradycardias. Three patients had marked sinus bradycardia while the other two had a regular rhythm with QRS of left bundle branch block morphology, with no P waves visible on the surface electrocardiogram. Four patients were in chronic hemodialysis three times a week, and one had severe post-traumatic hemorrhage. In three patients, hyperkalemia had been precipitated by food intoxication. In one case the cause was unknown while, in the last case, hyperkalemia was due to rapid infusion of stored blood and solutions containing high concentrations of potassium. Transesophageal atrial pacing was performed in all cases utilizing a bipolar catheter introduced into the esophagus and a constant current generator delivering square wave pulses of 10 msec duration and 19-28 mA intensity. Atrial capture, followed by impulse conduction to the ventricles, was constant in all cases, being performed for between 15 and 35 minutes until a normal sinus rhythm was restored. The procedure was well tolerated. The advantages of this procedure as opposed to invasive ventricular pacing are discussed.  相似文献   
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This case-report shows that high frequency repetitive Transcranial Magnetic Stimulation (hf-rTMS), applied to the left prefrontal cortex, may improve the linguistic skills in Primary Progressive Aphasia (PPA). The patient's performance was evaluated on a battery of language production and memory span tasks, before and after two hf-rTMS treatments and one SHAM treatment. We observed a significant and lasting improvement of the patient's performance on verb production following the application of hf-rTMS versus Baseline and SHAM conditions. This finding suggests that hf-rTMS may directly strengthen the neural connections within an area of metabolic dysfunction and encourages the use of rTMS as an alternative therapeutic tool for neurodegenerative forms of aphasia.  相似文献   
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