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91.
目的 探讨系统性红斑狼疮(SLE)患者活动性发热的临床特点并进行相关性分析.方法 由各参研单位根据统一方式收集病历资料,总结江苏省1999-2009年住院SLE患者的临床资料及治疗情况,分析发热与SLE的临床表现、免疫学指标、疾病活动及治疗情况间的关系.组间的计数资料比较采用x2检验,非正态分布的计量资料比较采用秩和检验,相关性分析采用Logistic回归分析.结果 1762例SLE患者纳入研究范围,其中活动性发热患者729例,非发热患者1033例,通过对照研究,发热组入院年龄、是否初治、光敏感、浆膜炎、神经精神系统累及、肝脾淋巴结肿大、血白细胞、血红蛋白、红细胞沉降率(ESR)、C反应蛋白(CRP)、丙氨酸转氨酶(ALT)、白蛋白、血清肌酐、补体C3、抗双链DNA (dsDNA)抗体、抗Sm抗体、SLE疾病活动指数(SLEDAI)评分、既往治疗与非发热组比较差异有统计学意义(尸<0.05);Logistic回归分析显示血白细胞异常[比值比(OR)=1.396,95%可信区间(CI)1.114~1.711,P=0.004]、CRP (OR=1.005,95%CI 1.002~1.009,P=0.002)、ALT( OR=1.003,95%CI 1.001 ~1.005,P=0.005)、血清肌酐(OR=0.997,95%CI 0.995~0.999,P=0.007)、血红蛋白(OR=0.986,95%CI0.981~0.992,P=0.000)、入院年龄(OR=0.984,95%CI 0.974~0.993,P=0.001)及环磷酰胺应用比例(OR=0.557,95%CI 0.382~0.813,P=0.002)与SLE 患者发热相关.结论 发热是SLE常见的临床表现之一.血白细胞下降、CRP升高、肝功能异常、贫血、入院年龄轻为SLE患者出现发热症状的危险因素,而肾累及、环磷酰胺应用为保护因素. 相似文献
92.
目的 研究基因组芯片检测大黄抑制鼠疫耶尔森菌分子机制的方法 .方法 使用的鼠疫耶尔森菌全基因组芯片包含4005条鼠疫耶尔森菌基囚.应用液体稀释法测定大黄对鼠疫耶尔森菌的最小抑菌浓度(MIC),基因芯片表达谱实验中,大黄作用鼠疫耶尔森菌的浓度为10×MIC,作用时间为30 min,提取并纯化鼠疫耶尔森菌总RNA,反转录合成cDNA,用Cy3,Cy5染料标记后,与鼠疫耶尔森菌全基因组芯片杂交,通过芯片扫描仪获得表达谱分析结果 .应用实时定量PCR技术对芯片结果 进行验证.结果 大黄对鼠疫耶尔森菌的MIC为0.02500 kg/L.获得了大黄作用鼠疫耶尔森菌的基因芯片表达谱.大黄作用鼠疫菌的明显差异表达基凶共有498个,上渊基闪358个,下凋基因140个.结论 应用鼠疫耶尔森菌全基因组DNA芯片可以进行大黄抑制鼠疫耶尔森菌的分子作用机制研究. 相似文献
93.
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep. 相似文献
94.
CRISTIANE MARIA DA COSTA‐SILVA FABIANO JEREMIAS JULIANA FELTRIN De SOUZA RITA De CÁSSIA LOIOLA CORDEIRO LOURDES SANTOS‐PINTO ANGELA CRISTINA CILENSE ZUANON 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2010,20(6):426-434
International Journal of Paediatric Dentistry 2010; 20: 426–434 Background. The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries. Objective. To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil. Methods. Children aged 6 to 12 years (n = 918) with all four‐first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Results. Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post‐eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values. Conclusion. Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries. 相似文献
95.
目的评价腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后的临床疗效。方法计算机检索Co-chrane Library、PubMed、Embase、SCI、CNKI、CBM、VIP、WANFANG DATA,纳入腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后疗效比较的随机对照试验,对纳入研究的方法学质量进行评价,用Cochrane协作网提供的RevMan 5.1软件对数据进行统计分析,并对统计结果进行系统评价。结果共纳入6个随机对照试验,共计1 885例患者。Meta分析结果显示:腹膜外切口单层缝合与常规分层缝合法在手术时间[MD=-17.09,95%CI(-19.32,-14.87)],术后切口感染率[RR=0.06,95%CI(0.03,0.12)],7 d内出院率[RR=1.17,95%CI(1.13,1.22)]方面差异均具有统计学意义,但两者在术后疼痛程度(需应用镇痛药物比率)[RR=1.05,95%CI(0.91,1.20)]方面的差异无统计学意义。结论目前研究表明,与常规分层缝合法相比,腹膜外切口单层缝合法能显著缩短化脓性或坏疽性阑尾炎患者的手术时间,降低术后切口感染率,提高7 d内出院率,但本研究纳入的样本量小且质量不高,因此,有必要开展更多高质量、多中心的随机盲法对照试验进一步予以证实其疗效。 相似文献
96.
AD Cohen†‡§ J Dreiher†‡ Y Shapiro¶ L Vidavsky† DA Vardy‡§ B Davidovici J Meyerovitch† †† ‡‡ 《Journal of the European Academy of Dermatology and Venereology》2008,22(5):585-589
Background Previous reports have shown an association between psoriasis and the metabolic syndrome, but there are only a few studies on the association between psoriasis and diabetes. Objectives To study the association between psoriasis and diabetes. Methods A cross‐sectional study was performed utilizing the database of Clalit Health Services (CHS). Patients who were diagnosed with psoriasis were compared with CHS enrolees without psoriasis regarding the prevalence of diabetes. Patients with diabetes were identified using the CHS chronic diseases registry. Chi‐squared tests were used to compare categorical parameters. Logistic regression models were used for multivariate analyses. Results The study included 16 851 patients with psoriasis and 74 987 subjects without psoriasis (control patients). The proportion of diabetes was significantly higher in patients above 35 years (P < 0.05). The age‐adjusted proportion of diabetes was significantly higher in psoriasis patients as compared to the control group [odds ratio (OR), 1.38, P < 0.05] and was similar in men and women (OR, 1.32, 1.45, respectively). A multivariate logistic regression model showed that psoriasis was significantly associated with diabetes, independently of age and gender (OR, 1.58, P < 0.001). Conclusions Our study supports previous reports of an association between psoriasis and diabetes. Dermatologists taking care of patients with psoriasis should be aware of this association and advise the patients to reduce additional risk factors such as smoking, hypertension or dyslipidemia. 相似文献
97.
DA Fairhurst M Shah 《Journal of the European Academy of Dermatology and Venereology》2008,22(10):1227-1231
Background There are few studies comparing the incidence of allergic contact dermatitis among different racial groups living within the same community. Objectives The objectives of this study were to compare white European patients with Fitzpatrick's skin phototypes (FSP) I to IV and patients from Indian, Pakistan and Bangladesh with FSP V living within the same community. Referral rates for patch testing, incidence of contact allergies and differences in contact allergens found were assessed. Method All patients referred to the Contact Dermatitis Unit at Dewsbury and District Hospital between 2004 and 2006, inclusive, were included in the study. All patients were patch tested to the British Contact Dermatitis Society standard series, plus other series according to their clinical history, occupational history and clinical findings. Results Four hundred and thirty‐five consecutive patients from the patch testing clinic were included in the study. Fewer patients from the Indian subcontinent underwent patch testing (11.5%) than would have been expected for the size of the local population (18%). Fewer patients from the Indian subcontinent (44%) had one or more positive reactions compared with the white European patients (56%). No significant differences in the contact allergens responsible were detected between the two racial groups. Conclusion There is a lower incidence of positive patch test results among patients with racial origins from the Indian subcontinent compared with white Europeans. This modest difference could be explained by a lower average age within the study population, and increased or differing exposure to contact allergens rather than demonstration of variability in the susceptibility to develop contact sensitivities following equal exposure. 相似文献
98.
Blood coagulation is initiated when plasma factor VII(a) binds to its essential cofactor tissue factor (TF) and proteolytically activates factors X and IX. Progressive inhibition of TF activity occurs upon its addition to plasma. This process is reversible and requires the presence of VII(a), catalytically active Xa, Ca2+, and another component that appears to be associated with the lipoproteins in plasma, a lipoprotein-associated coagulation inhibitor (LACI). A protein, LACI(HG2), possessing the same inhibitory properties as LACI, has recently been isolated from the conditioned media of cultured human liver cells (HepG2). Rabbit antisera raised against a synthetic peptide based on the N-terminal sequence of LACI(HG2) and purified IgG from a rabbit immunized with intact LACI(HG2) inhibit the LACI activity in human serum. In a reaction mixture containing VIIa, Xa, Ca2+, and purified LACI(HG2), the apparent half-life (t1/2) for TF activity was 20 seconds. The presence of heparin accelerated the initial rate of inhibition threefold. Antithrombin III alpha alone had no effect, but antithrombin III alpha with heparin abrogated the TF inhibition. LACI(HG2) also inhibited Xa with an apparent t1/2 of 50 seconds. Heparin enhanced the rate of Xa inhibition 2.5-fold, whereas phospholipids and Ca2+ slowed the reaction 2.5-fold. Xa inhibition was demonstrable with both chromogenic substrate (S-2222) and bioassays, but no complex between Xa and LACI(HG2) could be visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Nondenaturing PAGE, however, showed that LACI(HG2) bound to Xa but not to X or Xa inactivated by diisopropyl fluorophosphate. Thus, LACI(HG2) appears to bind to Xa at or near its active site. Bovine factor Xa lacking its gamma-carboxyglutamic acid-containing domain, BXa(-GD), through treatment with alpha-chymotrypsin, was used to further investigate the Xa requirement for VIIa/TF inhibition by LACI(HG2). LACI(HG2) bound to BXa(-GD) and inhibited its catalytic activity against a small molecular substrate (Spectrozyme Xa), though at a rate approximately sevenfold slower than native BXa. Preincubation of LACI(HG2) with saturating concentrations of BXa(-GD) markedly retarded the subsequent inhibition of BXa. The VII(a)/TF complex was not inhibited by LACI(HG2) in the presence of BXa(-GD), and further, preincubation of LACI(HG2) with BXa(-GD) slowed the inhibition of VIIa/TF after the addition of native Xa. The results are consistent with the hypothesis that inhibition of VII(a)/TF involves the formation of a VIIa-TF-XA-LACI complex that requires the GD of XA.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
99.
100.
Single-acquisition chemical-shift imaging of a binary system with use of stimulated echoes 总被引:1,自引:0,他引:1
A method for separating binary chemical-shift components with a single image data acquisition by means of stimulated echoes is demonstrated. With a strategy analogous to the modified Dixon method, three stimulated echoes were acquired to form three complex images. In each of the images, the complex pixel intensities were imparted, by design of the pulse sequence, with a phase factor carrying chemical-shift or field inhomogeneity information. With these three images, true fat/water separation can be obtained in biologic tissues. Studies at high field strength (4.7 T) on a toluene phantom, a pseudo-binary chemical-shift system, were used to evaluate the applicability of the method. Its clinical feasibility was demonstrated on a healthy human subject in a 0.6-T whole-body imaging system. 相似文献