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61.
62.
Several adverse effects have been reported under antiretroviral therapy containing protease inhibitors. We report a further case of avascular necrosis of both femoral heads in an HIV-infected patient treated with protease inhibitor containing antiretroviral therapy. 相似文献
63.
Manderscheid M Messmer UK Franzen R Pfeilschifter J 《Journal of the American Society of Nephrology : JASN》2001,12(6):1151-1163
Mesangial cells and RAW 264.7 macrophages respond to different nitric oxide (NO) donors within 16 to 24 h or 6 to 8 h, respectively, with apoptotic cell death. RAW 264.7 macrophages also die in response to endogenous NO production. In contrast, endogenous NO production fails to significantly induce cell death in mesangial cells. It was hypothesized that differences in the expression of antiapoptotic proteins, in particular the inhibitor of apoptosis (IAP) protein family, might be responsible for this cell type-specific behavior. Therefore, IAP expression was investigated in relation to apoptosis induction in response to NO and cytokines in both cell types. In mesangial cells, interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha induced cellular inhibitor of apoptosis 1 (cIAP1) mRNA expression within 3 h. In contrast, X chromosome-linked inhibitor of apoptosis (XIAP) mRNA levels remained unaffected by cytokines. Although coincubation of cells with IL-1beta and tumor necrosis factor-alpha or IL-1beta and basic fibroblast growth factor resulted in synergistic induction of inducible NO synthase, comparable potentiating effects on cIAP1 induction were absent. Exogenously released NO from NO donors promoted cIAP1 mRNA upregulation in mesangial cells, whereas XIAP mRNA was downregulated. However, the changes observed on the mRNA level were not adequately translated to the protein level, and corresponding values for cIAP1 and XIAP were only slightly affected. In contrast, in lipopolysaccharide/interferon-gamma-stimulated RAW 264.7 macrophages, massive NO-dependent downregulation of cIAP1 and XIAP protein levels, which correlated temporally with the induction of apoptosis, was observed. This effect was at least partially reversed by N(G)-monomethyl-L-arginine, an inhibitor of NO synthase activity. In summary, a direct correlation between the downregulation of IAP protein levels and the induction of apoptosis by endogenous NO was observed in macrophages. In contrast, a stable level of IAP protein in mesangial cells might represent a mechanism for the resistance of the cells to endogenously produced NO. 相似文献
64.
65.
R Muwonge CG Mbalawa N Keita A Dolo H Nouhou M Nacoulma JN Malanda M Koulibaly S Bayo R Sankaranarayanan for the IARC Multicentre Study Group on Cervical Cancer Early Detection 《BJOG : an international journal of obstetrics and gynaecology》2009,116(6):829-837
Objective The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design Cross-sectional study.
Setting Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population Women aged 25–59 years.
Methods A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa. 相似文献
Design Cross-sectional study.
Setting Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population Women aged 25–59 years.
Methods A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa. 相似文献
66.
Zusammenfassung.
Das kürzliche Auftreten des schweren akuten
respiratorischen Syndroms (SARS) ist das wichtigste Ereignis in
der Epidemiologie infektiöser Erkrankungen. Es wird durch ein
neu entdecktes und vermutlich beim Menschen neu aufgetretenes
Coronavirus verursacht. Durch internationale Kooperation und
schnelle Reaktion konnte der Erreger rasch identifiziert und
charakterisiert werden, die Epidemie ließ sich erfolgreich
eindämmen. Die hohe Komplikationsrate und die häufige
nosokomiale Übertragung dieses Erregers haben in den Zentren der
Epidemie viele Probleme verursacht.Die HIV-Infektion ist global weiter auf dem Vormarsch,
nach Afrika und Südostasien sind nun auch die Länder Osteuropas
und Zentralasien von dieser Pandemie bedroht. Präventivmaßnahmen
und die Einführung der modernen antiretroviralen Therapie machen
in Ländern mit hoher Prävalenz und Inzidenz Fortschritte, bisher
nur mit geringen Auswirkungen auf epidemiologische Trends. Die
Maßnahmen der WHO und anderer internationaler Organisationen zur
Eindämmung oder gar Elimination wichtiger Infektionskrankheiten
schreiten nur mühsam voran und haben mit vielen Schwierigkeiten
zu kämpfen. Ein Einsatz von Infektionserregern in militärischen
Auseinandersetzungen oder auch bei terroristischen Anschlägen
ist in den letzten Jahren vermehrt diskutiert und gefürchtet
worden; Anstrengungen richten sich hier vor allem auf die rasche
Erkennung und Prävention solcher Anschläge. Die Befürchtungen
einer rasch steigenden Zahl von Patienten mit der neuen Variante
der Creutzfeldt-Jakob-Erkrankung haben sich glücklicherweise
bisher nicht bestätigt. 相似文献
67.
目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1~L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。 相似文献
68.
Fifty samples of pleural fluid, collected from consecutive patients in a thoracic clinic who had diagnostic thoracentesis, were studied prospectively. Pleural fluid protein was of value in differentiating transudates from exudates. Pleural fluid red cell counts, white blood cell counts, and differential white blood cell counts have no specificity and no usefulness in the differential diagnosis of the origin of the effusion. Pleural fluid cytology was positive in 60% of all the malignancies studied in this series; for the group with metastatic breast carcinoma, there was a 78% positive pleural fluid cytology. Differential white cell counts revealed tumor cells in 45% of malignant effusions. In our experience, the finding of tumor cells is the only useful finding in differential cell counts of the pleural fluid. 相似文献
69.
目的:探讨颈椎椎后肌肉组织Na -K -ATP酶活性变化与颈椎病的关系。资料来源:应用计算机检索PubMed1988-01/2004-12相关骨骼肌损伤与肌组织Na -K -ATP酶关系的文献,检索词“Na -K pump,Na -K -ATPase,muscle”,限定文献语言种类为English。同时计算机检索CNKI1990-01/2005-12相关Na -K -ATP酶与骨骼肌损伤的关系及颈椎病发病病因的文献,检索词“Na -K -ATP酶,骨骼肌,颈椎病病因”,限定文献语言种类为中文。资料选择:对资料进行初审,选取包括Na -K -ATP酶与肌组织损伤关系的文献,开始查找全文。纳入标准:Na -K -ATP酶活性变化与骨骼肌损伤密切相关的文献研究。排除标准:重复研究,Meta分析类文章。资料提炼:共检索到939篇关于Na -K -ATP酶与骨骼肌损伤相关方面的文献,最终纳入20篇符合标准的文献。资料综合:众多研究表明,Na 、K 与骨骼肌的兴奋、收缩、疲劳有密切关系,而Na -K -ATP酶又是调节细胞内外Na 、K 浓度必不可少的高分子蛋白,也就是说,骨骼肌一系列活动均离不开Na -K -ATP酶,Na -K -ATP酶活性变化与骨骼肌损伤是相互影响的。而强迫屈颈体位作为颈椎病发病的危险因素之一,可使颈椎椎后肌肉Na -K -ATP酶活性降低,酶活性降低致使肌细胞损伤,并最终导致骨骼肌损伤而发病。结论:以颈椎椎后肌肉酶活性的变化来阐释中医药对颈椎病确切疗效的相关研究未见,这有待于进一步研究,以充分展示中医药在颈椎病等相关疾病中的治疗优势。 相似文献
70.
Nova Hambersom Minas Joerg Meister Rene Franzen Norbert Gutknecht Friedrich Lampert 《Lasers in medical science》2010,25(6):835-840
The aim of this study was to determine the amount of intra-canal dentine removed with an erbium, chromium:yttrium–scandium–gallium–garnet
(Er,Cr:YSGG) laser using different endodontic tips and different power settings. Ninety intact extracted bovine teeth were
selected as samples. After sectioning the roots and preparing the testing cylinders, we divided the samples into three main
groups (A, B, C), with further subdivision of each group to be irradiated with three different powers (1500 mW, 1750 mW and
2000 mW). An Er,Cr:YSGG laser system (2.78 μm, 140 μs, 20 Hz and 65% water to 35% air ratio) was used for irradiation, and
the loss of intra-canal dentine mass was calculated by the difference between the initial and final sample masses. Data were
analysed with Kolmogorov–Smirnov, analysis of variance (ANOVA) and Tukey tests. At a significance level of α = 1%, the results
showed statistically significant differences (P < 0.0001) between different tip groups, regarding both the ablation rate and the ablation efficiency criteria. With regard
to the three irradiation power settings, statistically significant difference were recorded only between groups C and A, for
the ablation rate criteria. The intra-canal ablation ability of the Er,Cr:YSGG laser improved with increasing power and/or
tip diameter. The latter exhibited a stronger influence on ablation rate and efficiency. Laser intra-canal ablation is an
important addition to the field of endodontics; nevertheless, further investigations and system improvements are required. 相似文献