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91.
目的 观察犬热缺血供体同种异体肺移植术后早期移植肺功能情况。方法 采用室温下热缺血 3 0min、LPD液灌注后 4℃保存 2 5h时的供肺 ,行右肺同种异体移植手术 7例 ,术前及监测恢复灌注 0 5 ,1,2及 4h的动脉血氧分压 (PaO2 )、肺动态顺应性 (Cdyn)、平均肺动脉压 (mPAP)、肺毛细血管楔压 (PCWP)和心输出量的变化 (CO)。结果 所有受体犬在观察期间均存活。恢复灌注 4h内的肺功能各指标变化差异无显著性 (P >0 0 5 ) ,或者虽然有统计学差异 ,但仍有较好的绝对水平。结论 热缺血 3 0min低温保存 2 5h的供肺可以维持生命 ,恢复灌注后 ,受缺血再灌注损伤的影响 ,在灌注后一段时间内 ,供肺功能下降 ,但仍可较好支持生命。 相似文献
92.
目的 建立一种可靠、简便的非同位素PCR方法检测脆性X综合征的突变基因。方法 采用生物素标记的CGG寡核苷酸探针,检测通过PCR扩增的FMR-1基因中CGG三核苷酸重复序列数目。从而判断所检样品中FMR—1基因是否正常。结果 该法可检测出正常人及携带者的CGG重复拷贝数。结论 该方法可以简便、安全、可靠地检测FMR—1基因中(CGG)n重复拷贝数,从而确定为正常人或携带者,可作为临床上筛查脆性X综合征的首选方法。 相似文献
93.
I. Ibarrola M. L. Sanz† P. M. Gamboa‡ A. Mir§ D. Benahmed§ A. Ferrer¶ M. C. Arilla A. Martínez J. A. Asturias 《Clinical and experimental allergy》2004,34(2):303-309
BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT. 相似文献
94.
J. A. Dunstan J. Roper L. Mitoulas† P. E. Hartmann† K. Simmer S. L. Prescott 《Clinical and experimental allergy》2004,34(8):1237-1242
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function. 相似文献
95.
Cow's milk-specific immunoglobulin E levels as predictors of clinical reactivity in the follow-up of the cow's milk allergy infants 总被引:2,自引:0,他引:2
M. C. García-Ara M. T. Boyano-Martínez J. M. Díaz-Pena M. F. Martín-Muñoz M. Martín-Esteban 《Clinical and experimental allergy》2004,34(6):866-870
Background IgE‐mediated cow's milk proteins (CMPs) allergy shows a tendency to disappear with age. The sooner tolerance is detected, the earlier the substitute diets can be suspended and the quicker family emotional hardship is alleviated. Objective To analyse the specific IgE levels to cow's milk and its proteins, which help to separate tolerant from no tolerant children in the follow‐up of infants with allergy to cow's milk. Patients and methods Sixty‐six infants diagnosed with IgE‐mediated allergy to CMPs were included in this prospective follow‐up study. Periodic reassessments were carried out every 6 months until they were 2‐years old and then, annually, until tolerance arose or until the last reassessment in which tolerance had not been achieved. Non‐tolerant infants were followed, at least, for a period of 3 years. In each visit, the same skin tests and determination of specific IgE (CAP System FEIA) for milk and its proteins were carried out. The open challenge test was repeated unless a clear transgression to milk, which came to be positive, had taken place within the previous 3 months in each of the follow‐up visits. Specific IgE levels to milk and its proteins, in different moments of the follow‐up were analysed by means of the receiver‐operating characteristic curve to predict clinical reactivity. Results Throughout the follow‐up 45 (68%) infants became tolerant. The follow‐up mean for tolerant infants was 21.2 months whereas for non‐tolerant infants it was 58 months. The specific IgE levels which were predictors of the clinical reactivity (positive predictive value (PPV)90%), grew as the age of the infants increased: 1.5, 6 and 14 kUA/L for milk in the age range 13–18 and 19–24 months and in the third year, respectively. Specific IgE levels to casein: 0.6, 3 and 5 kUA/L, respectively, predicted clinical reactivity (PPV90%) in the different analysed moments of the follow‐up. The cut‐off points: 2.7, 9 and 24 kUA/L for milk and 2, 4.2 and 9 kUA/L for casein, respectively, predicted clinical reactivity with an accuracy 95% corresponding to a specificity of 90%. Conclusions Monitorization of specific IgE concentration for milk and casein by means of the CAP system in allergic children to CMPs allows us to predict, to a high degree of probability, clinical reactivity. Age factor must be taken into account to evaluate the specific IgE levels which are predictors of tolerance or clinical reactivity. 相似文献
96.
P. Botas E. Delgado G. Castaño C. Díaz de Greñu J. Prieto F. J. Díaz-Cadórniga 《Diabetic medicine》2003,20(11):904-908
AIMS: To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. METHODS: A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. RESULTS: The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K=0.42; WHO-1985/WHO-1999 80%, K=0.88; ADA-1997/WHO-1999 48%, K=0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose > or =11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. CONCLUSIONS: The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l. 相似文献
97.
98.
脂肪干细胞免疫学性状的初步实验观察 总被引:3,自引:0,他引:3
目的初步研究脂肪干细胞(Adiposederivedstemcells,ADSC)表面免疫分子的表达以及体外免疫调节功能,以期为组织工程提供同种异体种子细胞来源。方法体外培养人脂肪抽吸术中获取的脂肪干细胞,体外培养至第二代,流式细胞仪检测免疫分子HLA、HLA、B7-1、B7-2、CD40的表达。1×105个/孔ADSC细胞分别刺激单一异体淋巴细胞或混合双向淋巴细胞反应,观察淋巴细胞增殖情况。同时观察ADSC经IFN-γ作用后,免疫分子表达与淋巴细胞增殖的调节情况。结果ADSC表达HLA类分子,但未检测到HLA类分子阳性表达。B7-1(CD80)、B7-2(CD86)、CD28、CD40未见明显阳性表达。人IFN-γ刺激48h后,HLA类分子表达明显增高,HLAI表达未见明显增高。异体或经IFN-γ作用的ADSC均未能刺激异体淋巴细胞增殖。同样数量的ADSC可明显抑制双相混合淋巴细胞增殖,经IFN-γ作用后抑制作用未见明显减弱。结论ADSC具有一定的体外调节淋巴细胞反应的能力,有可能成为组织工程同种异体细胞来源。 相似文献
99.
Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (Pes using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both Pes and airway opening pressure (Pao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between Pes and Pao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of Pao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔPao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔPes was within 10% of ΔPao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc. 相似文献
100.
We reported a case of photoleukomelanodermatitis (Kobori) type drug eruption due to afloqualone (Arofuto®). The patient was given afloqualone and imipramine hydrochloride (Chrytemin®) for cervical spondylosis from November of 1990. Edematous erythema with slight itching appeared on the sun-exposed areas in December of 1990. As drug eruption was suspected, drugs were ceased, and the cutaneous lesions almost disappeared but pigmentations and depigmentations developed in spots in sun-exposed areas in March of 1991. Photopatch and oral challenge tests were positive. 相似文献