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21.
Agmatine has been identified as a clonidine-displacing substance in extracts from bovine brain. We studied its effect on cardiovascular regulation and the role played in this effect by 2-adrenoceptors.In conscious rabbits, agmatine 10 g kg–1 injected intracisternally (i.e.) caused no change, whereas agmatine 30, 100 and 300 g kg–1 i.e. increased renal sympathetic nerve firing, the plasma concentration of noradrenaline and adrenaline and arterial blood pressure. Heart rate tended to be decreased. Yohimbine 1.5 g kg–1 i.e. caused no change, whereas yohimbine 5, 15 and 50 g kg–1 increased renal sympathetic nerve activity, the plasma concentration of noradrenaline and adrenaline, blood pressure and heart rate. In rabbit brain cortex slices preincubated with [3H]-noradrenaline, agmatine 1 to 100 M did not modify the electrically evoked overflow of tritium (either 4 pulses at 100 Hz or 36 pulses at 3 Hz). The evoked overflow was reduced by 5-bromo-6-(2-imidazolin-2-ylamino)quinoxaline (UK 14304) 0.03 to 30 nM (4 pulses at 100 Hz), and this inhibition was not affected by agmatine 10 and 100 M. Agmatine did not change the basal efflux of tritium.The results show that agmatine, like yohimbine, causes central sympathoexcitation when given i.e., but agmatine differs from yohimbine in that it does not increase heart rate. Agmatine acts neither as an agonist nor as an antagonist at the 2-autoreceptors in rabbit brain cortex. 2-Adrenoceptors, therefore, are probably not involved in its cardiovascular effects. An action at imidazoline receptors in the medulla oblongata or some other hitherto unknown mechanism may be responsible for the sympathoexcitation.  相似文献   
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ObjectivesTo develop an international consensus on managing penile cancer patients during the COVID-19 acute waves. A major concern for patients with penile cancer during the coronavirus disease 2019 (COVID-19) pandemic is how the enforced safety measures will affect their disease management. Delays in diagnosis and treatment initiation may have an impact on the extent of the primary lesion as well as the cancer-specific survival because of the development and progression of inguinal lymph node metastases.Materials and methodsA review of the COVID-19 literature was conducted in conjunction with analysis of current international guidelines on the management of penile cancer. Results were presented to an international panel of experts on penile cancer and infection control by a virtual accelerated Delphi process using 4 survey rounds. Consensus opinion was defined as an agreement of ≥80%, which was used to reconfigure management pathways for penile cancer.ResultsLimited evidence is available for delaying penile cancer management. The consensus rate of agreement was 100% that penile cancer pathways should be reconfigured, and measures should be developed to prevent perioperative nosocomial transmission of COVID-19. The panel also reached a consensus on several statements aimed at reconfiguring the management of penile cancer patients during the COVID-19 pandemic.ConclusionsThe international consensus panel proposed a framework for the diagnostic and invasive therapeutic procedures for penile cancer within a low-risk environment for COVID-19.  相似文献   
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Oral human papillomavirus (HPV) carriage rates were investigated in relation to genital HPV carriage in women with HPV‐associated cervical lesions and male partner of such women, including several couples, in comparison with healthy individuals. Buccal and lingual mucosa of 60 males and 149 females with healthy oral mucosa and without known genital lesion, genital and oral mucosa of further 40 females with cervical high‐grade squamous intraepithelial lesion (HSIL) and 34 male sexual partners of women with HSIL (including 20 couples) were sampled. HPV DNA was detected using MY/GP PCR. Genotype was determined by sequencing or restriction fragment length polymorphism. Virus copy numbers were determined by real‐time PCR. Overall, oral HPV carriage rate was 5.7% (12/209) in healthy individuals; average copy number was 5.8 × 102 copies/1 μg DNA; male and female rates were comparable. Oral carriage in women with HSIL was significantly higher, 20.0% (8/40, P = 0.003); males with partners with HSIL showed a carriage rate of 17.6% (6/34), copy numbers were similar to the healthy controls. In contrast, genital carriage rate (52.9%, 18/34 vs. 82.5%, 33/40; P = 0.006) and average copy number were lower in males (5.0 × 105 vs. 7.8 × 105 copies/1 μg DNA; P = 0.01). Oral copy numbers in these groups and in healthy individuals were comparable. High‐risk genotypes were dominant; couples usually had the same genotype in the genital sample. In conclusion, genital HPV carriage is a risk factor of oral carriage for the individual or for the sexual partner, but alone is not sufficient to produce an oral HPV infection in most cases.  相似文献   
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Roma people are underprivileged, neglected population worldwide, with severe healthcare problems. They have significantly increased prevalence of cardiovascular morbidity, presumably related to their poor social status, alcohol consumption and smoking habits. Assuming that genetic background also plays a role in their susceptibility for cardiovascular diseases, we hypothesized that APOA5 gene polymorphisms, an important role-player in lipid metabolism and in the development of metabolic syndrome and cardio/cerebrovascular events, may also be involved. We examined four APOA5 polymorphisms in 363 Roma and 404 Hungarian DNA samples. For rs662799, rs2266788, rs207560 and rs3135506 we found elevated plasma triglyceride levels in the risk allele carriers compared to non-carriers in both populations. At least a two-fold significant increase was detected in minor allele frequencies in Roma when compared to Hungarians, except the rs2266788 variant. Haplotype analysis revealed significant increase of APOA5*2, APOA5*4 in Roma, as opposed to the higher levels of APOA5*5 found in Hungarians. Different linkage disequilibrium was found between rs207560 and rs3135506 variants in Roma compared to Hungarians. The profound differences observed in almost all APOA5 polymorphisms in Roma require special attention, since these variants are known to associate with cardio/cerebrovascular susceptibility.  相似文献   
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Diffuse large B-cell lymphoma (DLBCL) is the most frequent, complex and heterogeneous lymphoma of adulthood. Heterogeneity is expressed at clinical, genetic, and molecular levels. It is known that BCL-6 expression is a favorable prognostic factor in DLBCL. However, the underlying mechanisms of BCL-6 expression in DLBCL relapse are not yet elucidated. Here, we present so far undescribed clinical phenomenon of switching BCL-6+ protein expression into BCL-6 expression in 19 of 41 relapsed DLBCL patients. The switch in relapsed DLBCL was associated with more aggressive clinical course of the disease. Bone marrow infiltration and high IPI risk were more often present in BCL-6 patients. Significantly increased biochemical parameters, such as LDH, beta-2 macroglobulin, CRP, and ferritin have been found, as well as significantly decreased serum Fe, TIBC, and hemoglobin. A Ki-67 proliferation marker was considerably high in relapsed DLBCL, but without significant differences between BCL-6+ and BCL-6 groups of patients. Thus, switching of the positive into negative BCL-6 expression during DLBCL relapse could be used as a prognostic factor and a valuable criterion for treatment decision.  相似文献   
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Sequence analysis was conducted on structural and non-structural genes of 7 strains of dengue virus type-3 (DENV-3 virus) isolated in Indonesia and Thailand in the year 1973, 1994, and 1998 from patients with different clinical manifestations. In general, sequence similarity among isolates was greater than 93%, indicating that the mutation rate of DENV-3 circulating in this region was not more than 7% in the last 3 decades and suggesting that sequences that may responsible for viral architectures and/or biological function were strictly conserved. Mutations unique to viral strains associated with specific clinical manifestations were not found. Alignment of PrM/M and E nucleic acid sequences followed by parsimony analysis of sequences obtained in this study and published elsewhere allowed generation of phylogenetic trees, demonstrating that DENV-3 strains isolated in Indonesia in 1998 belonged to a separate cluster (subtype 2) from those isolated between 1973-1985 (subtype 1).  相似文献   
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