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排序方式: 共有314条查询结果,搜索用时 15 毫秒
1.
E J Brewer E H Giannini N Kuzmina L Alekseev 《The New England journal of medicine》1986,314(20):1269-1276
One hundred sixty-two children with severe juvenile rheumatoid arthritis were entered in a randomized, double-blind, placebo-controlled 12-month clinical trial designed to establish the efficacy and safety of two slower-acting antirheumatic drugs, penicillamine and hydroxychloroquine. The study was a cooperative effort of the United States and the Soviet Union. One group of subjects received 10 mg of penicillamine per kilogram of body weight per day, another group received 6 mg of hydroxychloroquine per kilogram daily, and a third group received placebo. All three groups were allowed a single concurrent nonsteroidal antiinflammatory drug, but no other antirheumatic medications, including corticosteroids. All three groups had dramatic improvement in many of the clinical and laboratory outcome variables after one year of study. There were no significant differences in efficacy between the penicillamine and placebo groups. Pain on movement was the only index of articular disease that was alleviated more by hydroxychloroquine than by placebo. Serious adverse drug reactions attributable to the active agents were rare. We were unable to demonstrate that, in the presence of a nonsteroidal antiinflammatory drug, either penicillamine or hydroxychloroquine is superior to placebo in the treatment of children with juvenile rheumatoid arthritis. 相似文献
2.
Jun Zhang Ciro R Martins Zoya B Fansler Kristina L Roemer Erik A Kincaid Karen S Gustafson Daniel F Heitjan Douglas P Clark 《Clinical cancer research》2005,11(18):6544-6549
PURPOSE: Anal intraepithelial neoplasia is associated with human papillomavirus infection and may progress to invasive squamous cell carcinoma (SCC), which is increasing in immunocompromised patients. We hypothesize that anal intraepithelial neoplasia is associated with abnormal DNA methylation and that detection of these events may be used to improve screening programs. EXPERIMENTAL DESIGN: Seventy-six patients were identified who underwent anal cytology screening and subsequent biopsy at our institution between 1999 and 2004. The specimens from these patients included 184 anal biopsies [normal, n = 57; low-grade squamous intraepithelial lesion (LSIL), n = 74; high-grade squamous intraepithelial lesion (HSIL), n = 41; and invasive SCC, n = 12] and 37 residual liquid-based anal cytology specimens (normal, n = 11; LSIL, n = 12; HSIL, n = 14). The methylation status of the following genes was determined for each biopsy and cytology sample using real-time methylation-specific PCR: HIC1, RASSF1, RARB, CDKN2A, p14, TP73, APC, MLH1, MGMT, DAPK1, and IGSF4. RESULTS: Methylation-specific PCR analysis of biopsy samples revealed that DNA methylation was more common in SCC and HSIL than LSIL and normal mucosa. Specifically, methylation of IGSF4 and DAPK1 was prevalent in SCC (75% and 75% of cases, respectively) and HSIL (59% and 71%, respectively) but was absent in LSIL and normal biopsy samples. Methylation profiles of cytologic samples were similar to those found in the biopsy samples. CONCLUSIONS: Aberrant DNA methylation is a frequent event in anal HSIL and SCC. Methylation of IGSF4 and DAPK1 is specific for HSIL and SCC, and may serve as a useful molecular biomarker. 相似文献
3.
Zoya M. Petrushenko Hang Zhao Helen I. Zgurskaya Valentin V. Rybenkov 《Antimicrobial agents and chemotherapy》2016,60(5):2949-2953
Condensins play a key role in the global organization of bacterial chromosomes. In Escherichia coli, the inactivation of its sole condensin MukBEF induces severe growth defects and renders cells hypersusceptible to novobiocin. We report here that this hypersusceptibility can be observed in TolC-deficient cells and is therefore unrelated to multidrug efflux. We further show that mutations in MukE that impair its focal subcellular localization potentiate novobiocin and that the extent of the potentiation correlates with the residual activity of MukE. Finally, both DNA gyrase and topoisomerase IV might partially complement novobiocin susceptibility in a temperature-dependent manner. These data indicate that the observed antibiotic susceptibility resides in both type II DNA topoisomerases and is efflux independent. Furthermore, novobiocin susceptibility is associated with the activity of MukBEF and can be induced by its partial inactivation, which makes the protein a plausible target for inhibition. 相似文献
4.
Examination of the biodiversity of horse strongylid communities was performed on 51 domestic horses from Southern Poland and
Western Ukraine by in vivo method. All horses were dewormed with macrocyclic lactone anthelmintics. Strongylids (34,715 specimens) were collected and
identified by morphological criteria. In Poland, 25 strongylid species were found. Five cyathostome species dominated in the
community. Large strongyles were found in 23.1 % of horses and composed 0.56 % of total strongylid number. General structure
of strongylid community was multimodal with dominant, subdominant, background and rare species. In Ukraine, 19 species were
found. Five cyathostome species dominated in the community. Strongylinae were found in 17.4 % of horses and composed 0.07%
of community. General structures of strongylid community were multimodal or bimodal depends on type of horse keeping conditions.
Regularity of anthelmintic treatment was found to be more influential on strongylid community structure than differences in
horse-keeping conditions at the both countries. 相似文献
5.
6.
The cost-effectiveness of HIV preventive measures among injecting drug users in Svetlogorsk, Belarus
Kumaranayake L Vickerman P Walker D Samoshkin S Romantzov V Emelyanova Z Zviagin V Watts C 《Addiction (Abingdon, England)》2004,99(12):1565-1576
AIM: To undertake a cost-effectiveness analysis of a harm reduction and HIV prevention project for injecting drug users (IDUs) in Eastern Europe. Economic evaluation methods were adapted to consider the effect of an 8-month financing gap that negatively impacted on project implementation. DESIGN: Financial and economic costs of implementing the intervention were analysed retrospectively. The data were also modelled to estimate the costs of a fully functioning project. Estimates of the intervention impact on sexual and drug injecting behaviour were obtained from existing pre- and post-intervention behavioural surveys of IDUs. A dynamic mathematical model was used to translate these changes into estimates of HIV infections averted among IDUs and their sexual partners. Projections of the potential effect of the shortfall in funding on the impact and cost-effectiveness of the intervention were made. SETTING: Svetlogorsk, Belarus, where in 1997 the IDU HIV prevalence was 74%. FINDINGS: The intervention averted 176 HIV infections (95% CI 60-270) with a cost-effectiveness of 359 dollars per HIV infection averted (95% CI 234-1054 dollars). Without the 2311 dollars reduction (7%) in financing, the estimated cost-effectiveness ratio of the project would have been 11% lower. The costing methods used to measure donated mass media can substantially influence cost and cost-effectiveness estimates. CONCLUSIONS: Harm reduction activities among IDUs can be cost-effective, even when IDU HIV prevalence and incidence is high. Relatively small shortfalls in funding reduce impact and cost-effectiveness. Increased and consistent allocation of resources to harm reduction projects could significantly reduce the pace of the HIV epidemic in Eastern Europe. 相似文献
7.
Takashi Hato Seth Winfree Rabih Kalakeche Shataakshi Dube Rakesh Kumar Momoko Yoshimoto Zoya Plotkin Pierre C. Dagher 《Journal of the American Society of Nephrology : JASN》2015,26(6):1347-1362
Preconditioning is a preventative approach, whereby minimized insults generate protection against subsequent larger exposures to the same or even different insults. In immune cells, endotoxin preconditioning downregulates the inflammatory response and yet, preserves the ability to contain infections. However, the protective mechanisms of preconditioning at the tissue level in organs such as the kidney remain poorly understood. Here, we show that endotoxin preconditioning confers renal epithelial protection in various models of sepsis in vivo. We also tested the hypothesis that this protection results from direct interactions between the preconditioning dose of endotoxin and the renal tubules. This hypothesis is on the basis of our previous findings that endotoxin toxicity to nonpreconditioned renal tubules was direct and independent of immune cells. Notably, we found that tubular protection after preconditioning has an absolute requirement for CD14-expressing myeloid cells and particularly, macrophages. Additionally, an intact macrophage CD14-TRIF signaling pathway was essential for tubular protection. The preconditioned state was characterized by increased macrophage number and trafficking within the kidney as well as clustering of macrophages around S1 proximal tubules. These macrophages exhibited increased M2 polarization and upregulation of redox and iron-handling molecules. In renal tubules, preconditioning prevented peroxisomal damage and abolished oxidative stress and injury to S2 and S3 tubules. In summary, these data suggest that macrophages are essential mediators of endotoxin preconditioning and required for renal tissue protection. Preconditioning is, therefore, an attractive model to investigate novel protective pathways for the prevention and treatment of sepsis. 相似文献
8.
Jeffrey L. Bennetzen Phillip SanMiguel Mingsheng Chen Alexander Tikhonov Michael Francki Zoya Avramova 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(5):1975-1978
For the most part, studies of grass genome structure have been limited to the generation of whole-genome genetic maps or the fine structure and sequence analysis of single genes or gene clusters. We have investigated large contiguous segments of the genomes of maize, sorghum, and rice, primarily focusing on intergenic spaces. Our data indicate that much (>50%) of the maize genome is composed of interspersed repetitive DNAs, primarily nested retrotransposons that insert between genes. These retroelements are less abundant in smaller genome plants, including rice and sorghum. Although 5- to 200-kb blocks of methylated, presumably heterochromatic, retrotransposons flank most maize genes, rice and sorghum genes are often adjacent. Similar genes are commonly found in the same relative chromosomal locations and orientations in each of these three species, although there are numerous exceptions to this collinearity (i.e., rearrangements) that can be detected at the levels of both the recombinational map and cloned DNA. Evolutionarily conserved sequences are largely confined to genes and their regulatory elements. Our results indicate that a knowledge of grass genome structure will be a useful tool for gene discovery and isolation, but the general rules and biological significance of grass genome organization remain to be determined. Moreover, the nature and frequency of exceptions to the general patterns of grass genome structure and collinearity are still largely unknown and will require extensive further investigation. 相似文献
9.
Anisakid nematodes parasitize the alimentary tracts of aquatic vertebrates, including northern fur seals (Callorhinus ursinus) (NFS). The main purpose of this study was to estimate the prevalence, intensity, and species composition of anisakids in NFSs on St. Paul Island, Alaska, and to analyze changes in NFS infection with these nematodes during the last decades. The study was carried out on St. Paul Island, Alaska, in July–August 2011–2013. Stomachs of 443 humanely harvested NFS males were collected from five separate haul-out areas. A total of 4,460 anisakid specimens were collected and identified by morphological criteria. Gross and histological examinations of stomachs were also performed. The overall prevalence of NFS infection was 91.2 %; overall mean intensity 10.9, and overall median intensity 6. Five species, Anisakis simplex s. l., Contracaecum osculatum s. l., Pseudoterranova decipiens s. l., P. azarazi and Phocascaris cystophorae, were found. The prevalence of Anisakis was 46.5 %, its intensity 7.5. The prevalence and intensity of Contracaecum, Pseudoterranova, and Phocascaris were 33.6 % and 3.5, 81.9 % and 6.5, and 5.2 % and 1.7, respectively. Significant differences in the prevalence of NFS infection were observed between separate haul-outs. Comparison of the present data with the results of studies performed in the North Pacific in the 1960s, showed a significant decrease in the intensity of NFS infection with anisakids during the last decades. The prevalence of mucosal lesions in NFS stomachs caused by anisakids also decreased from 92 to 20.9 %. Possible reasons for the changes in NFS infection with anisakids are discussed. 相似文献
10.