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A new serological test, diffusion in gel-enzyme-linked immunosorbent assay (DIG-ELISA) was developed and compared with the microscopic agglutination test (MAT) for the serological diagnosis of leptospirosis. The results suggest that DIG-ELISA is a viable alternative to the MAT because of its simplicity, sensitivity, versatility and potential for standardisation.  相似文献   
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BACKGROUND: Levels of IgE antibody to egg white of greater than 7 kIU/L are highly predictive of clinical reactivity to egg, and lower levels often require evaluation with oral food challenge (OFC) to establish definitive diagnosis. OFCs have inherent risks, and diagnostic criteria indicating high likelihood of passing would be clinically useful. OBJECTIVE: We sought to determine whether the size of the skin prick test (SPT) to egg white adds diagnostic utility for children with low egg white-specific IgE antibody levels. METHODS: A retrospective analysis of clinical history, egg white-specific IgE antibody levels, SPT responses, and egg OFC outcomes was performed. RESULTS: Children who passed (n = 29) egg OFCs and those who failed (n = 45) did not differ significantly in age, clinical characteristics, or egg white-specific IgE levels. There were, however, significant differences between both egg white SPT wheal response size and egg/histamine SPT wheal index. Children who failed egg OFCs had a median wheal of 5.0 mm; those who passed had a median wheal of 3.0 mm (P = .003). Children who failed egg OFCs had a median egg/histamine index of 1.00; those who passed had a median index of 0.71 (P = .001). For egg white-specific IgE levels of less than 2.5 kIU/L, an SPT wheal of 3 mm or an egg/histamine index of 0.65 was associated with a 50% chance of passing. CONCLUSION: In children with low egg white-specific IgE levels, those with smaller SPT wheal responses to egg were more likely to pass an egg OFC than those with larger wheal responses. The size of the egg white SPT response might provide additional information to determine the timing of egg OFC. CLINICAL IMPLICATIONS: The size of the egg white SPT wheal response might provide the clinician with additional information to determine the timing of egg OFC in children with low egg white-specific IgE antibody levels.  相似文献   
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ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects.  相似文献   
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目的探讨瘦素质量浓度与早期静脉营养及生长发育的关系。方法新疆医科大学第一附属医院新生儿科于2005-01—2006-02,将收治的86例早产适于胎龄儿用随机数字表法分为观察组(早期微量喂养同时辅助胃肠外营养组)45例和对照组(单纯早期微量喂养组)47例,分别测定脐血及第7天血清瘦素质量浓度,同时监测营养状况和生长发育指标,并作对比分析。结果(1)观察组与对照组脐血瘦素质量浓度分别为(4.6±3.7)ng/mL、(4.8±2.2)ng/mL,生后第7天两组瘦素质量浓度分别为(4.3±2.2)ng/mL、(3.1±1.7)ng/mL。对照组第7天血清瘦素质量浓度明显低于脐血(P<0.05),而观察组其差异无统计学意义(P>0.05)。(2)脐血瘦素质量浓度与出生体重、胎龄成正相关(r=0.56、r=0.67)。(3)观察组第7天热卡及蛋白质摄入量、血清瘦素质量浓度、皮褶厚度变化值与对照组相比,差异有统计学意义(P<0.05)。结论对早产儿应尽早喂养,同时需要胃肠外营养作为肠内营养的补充。瘦素可作为新生儿营养效果判定的实验室指标之一。  相似文献   
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Dendritic cells (DCs) are critical to the outcome of many viral infections. Questions still remain as to the relevance of artificially generated DCs in models of in vivo immune responses. We compared different DC generation pathways, in terms of phenotypic expression, cytokine production, apoptosis, and T cell proliferation, following viral infection. Direct viral infection of monocytes or monocytes cultured with supernatants from virally infected lung epithelial cells (A549 DCs) induce distinct DC subsets compared with viral infection of artificially generated IL-4 DCs and IFN-DCs. These virally infected DC subsets stimulated different cytokine secretion profiles and displayed contrasting sensitivities to viral-induced apoptosis. It is most interesting that we observed marked differences in the proliferation of purified CD3+ T cells from the virally infected DC subsets. In conclusion, artificially generated DCs skew immune responses to viral infections, and direct viral infection of monocytes and DCs, generated from monocytes cultured with supernatants from infected epithelial cells, appears to be a more relevant pathway of producing DCs, which mimic those generated in vivo.  相似文献   
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