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101.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age. 相似文献
102.
Israel Lerman Liliana Lozano Antonio
R. Villa Sergio Hernndez-Jimnez Katie Weinger A. Enrique
Caballero Carlos Aguilar Salinas Maria Luisa Velasco Francisco Javier Gmez-Prez Juan
A. Rull 《Biomedicine & Pharmacotherapy》2004,58(10):566-570
To examine the relationship between demographic, clinical and psychosocial variables and diabetes self-care management in Mexican type 2 diabetic patients. Cross-sectional study of 176 consecutive patients with type 2 diabetes aged 30-75 years, attending a tertiary health-care center in Mexico City. A brief medical history and previously validated questionnaires were completed. The study group consisted of 64 males/112 females, aged 55 +/- 11 years, mean diabetes duration of 12 +/- 8 years and HbA1c of 9.0 +/- 2.0%, 78.4% reported following the correct dose of diabetes pills or insulin, 58% ate the recommended food portions, and 44.3% did exercise three or more times per week. A good adherence to these three recommendations was observed in only 26.1% of the patients. These patients considered as a group were characterized by a greater knowledge about the disease (P < 0.00001), regular home blood glucose monitoring (P < 0.01), an inner perception of better diabetes control (P = 0.007), good health (P = 0.004) and better communication with their physician (P < 0.02). A poor adherence to two or the three main diabetes care recommendations was associated with a depressive state (OR 2.38, 95% CI 1.1-4.9, P < 0.01) and a history of excessive alcohol intake (OR 4.03, 95% CI 1.1-21.0, P = 0.03). Poor adherence to standard diabetes care recommendations is frequently observed in patients with type 2 diabetes attending a specialized health care center in Mexico City. Depression must be identified and treated effectively. 相似文献
103.
H. GALLION W.A. CHRISTOPHERSON† R.L. COLEMAN‡ L. DEMARS§ T. HERZOG S. HOSFORD¶ H. SCHELLHAS# A. WELLS & B.-U. SEVIN†† 《International journal of gynecological cancer》2006,16(1):194-201
The study objective was to determine the effectiveness of a phenotypic chemoresponse assay in predicting response to chemotherapy measured by progression-free interval (PFI) in a retrospective series of ovarian cancer patients whose tumor specimens had been tested with the ChemoFx assay. A statistically significant correlation between assay prediction of response and PFI was observed in 256 cases with an exact or partial match between drug(s) assayed and received. In 135 cases with an exact match, the hazard ratio for progression of the resistant group was 2.9 (confidence interval [CI]: 1.4-6.3; P < 0.01) compared to the sensitive group and 1.7 (CI: 1.2-2.5) for the intermediate compared to the sensitive group. The median PFI for patients treated with drugs assayed as resistant was 9 months, 14 months for those with drugs assayed as intermediately sensitive, and PFI had not been achieved for those with drugs assayed as sensitive. These data indicate that the ChemoFx assay is predictive of PFI in ovarian cancer. As the majority of ovarian cancers display different degrees of response to different chemotherapy agents ex vivo, the incorporation of assay information into treatment selection has the potential to improve clinical outcomes in ovarian cancer patients. 相似文献
104.
高性能战斗机改装体检飞行员的耳功能分析 总被引:6,自引:3,他引:3
目的 分析高性能战斗机改装体检飞行员的咽鼓管功能、前庭功能和听功能状况。方法 对改装体检的196名飞行员的耳功能资料进行分析。结果 ①声导抗示196例392耳中193例368耳为A型曲线,6例7耳为AD型曲线,15例17耳为C型曲线。196例392耳均无声反射衰减;②眼震电图示196例前庭功能均正常:③纯音测听以气导在500、1000、2000、3000Hz的平均听阈表示,196例的结果为左耳12.58dB HL;右耳12.48dB HL,但37例47耳有高频区噪声性听损伤的表现。结论 参与高性能战斗机改装体检的飞行员,其耳功能状况总体良好,但部分有噪声性听损伤的应随访观察。 相似文献
105.
大鼠腓总神经“π”式桥接于胫神经后再生神经的电生理溯源 总被引:5,自引:1,他引:4
目的 研究大鼠胫神经原位桥接切断的腓总神经,观察腓总神经再生程度、神经纤维的来源等。方法 将断裂的腓总神经近端和远端分别就近与胫神经施行端侧吻合,存活18个月后,电生理检测再生神经纤维的动作电位传导,取腓总神经远段行光镜及电镜观察神经纤维再生数量及状态。结果 远段腓总神经有明显的神经纤维再生,远段腓总神经通过邻近神经的桥接与近段腓总神经之间有动作电位传导。结论 断裂腓总神经“π”式桥接于胫神经,部分再生神经纤维可能来源于原腓总神经近段,部分来自胫神经。 相似文献
106.
Theoretical and simulation evidence is presented in support of the idea that the optimal manner of determining blood flow from MR perfusion studies is not necessarily obtained by setting experimental conditions to maximize either the arterial input or the measured tissue concentration level for a particular echo time (TE). The noise power in the contrast concentration curve is associated with its peak because of the nonlinear relationship between the contrast concentration and MR signal intensity curves. The optimum signal-to-noise ratio (SNR), SNR(C), for a particular contrast concentration curve can be obtained when the experimental concentration level and TE are adjusted to produce an MR intensity curve whose signal loss is 63% of the precontrast MR signal intensity. It is demonstrated that the stability of the singular valued decomposition (SVD) deconvolution approach to determine blood flow parameters is increased when the tissue curve maximum signal loss is in the range of 40-80%. The accuracy and stability of the SVD-determined blood flow parameters are affected by deviations from these optimum conditions in a manner that depends on the mean transit time (MTT) associated with the residue function. It is recommended that the experimental TE value be set so that neither the tissue nor the arterial curves are placed a region of rapidly deteriorating SNR(C). 相似文献
107.
绞股蓝多甙100mg/kg·d-1×4wk灌胃给药,观察结果表明该物具有降低实验性高脂血症家兔的血脂水平及血清过氧化脂质、心肌褐脂质含量的作用。 相似文献
108.
研究补肾抗衰口服液对大鼠衰老模型免疫器官胸腺和脾脏的影响.结果显示,模型组大鼠胸腺和脾脏重量减轻,胸腺重/体重比值、脾重/体重比值减小,胸腺组织学观察,显示萎缩改变;药物组大鼠胸腺和脾脏重量、胸腺重/体重、脾重/体重比值接近正常对照组,胸腺组织学观察,未显示萎缩改变.本研究结果表明,补肾抗衰口服液能延缓胸腺和脾脏萎缩,保护机体的正常免疫功能,提示该药有抗衰老的作用. 相似文献
109.
M. K. Watson L. S. Jakobson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(2):273-280
In the present study, a kinematic analysis was made of unconstrained, natural prehension movements directed toward an object
approaching the observer on a conveyor belt at one of three constant velocities, from one of three different directions (head-on
or along the fronto-parallel plane coming either from the subject′s left or right). Subjects were required to grasp the object
when it reached a target located 20 cm directly in front of the hand′s start position. The kinematic analysis revealed that
both the transport and grasp components of the movement changed in response to the experimental manipulations, but did so
in a manner that guaranteed that, for objects approaching from a given direction, hand closure would begin at a constant time
prior to object contact (regardless of the object’s approach speed). The kinematic analysis also revealed, however, that the
onset of hand closure began earlier with objects approaching from the right than from other directions – an effect which would
not be predicted if time to contact was the key variable controlling the onset of hand closure. These results, then, lend
only partial support to the theory that temporal coordination between the transport and grasp components of prehension is
ensured through their common dependence on time to contact information.
Received: 20 September 1996 / Accepted: 16 June 1997 相似文献
110.
为了探讨动脉分支处及小动脉端侧吻合处的血液流动方式,采用微循环电视显微镜成像技术,活体观察大鼠肠系膜微动脉分支区域血液流动方式和红细胞流变行为,研究动脉血流方向的改变对血流方式的影响。实验中观察到,在形态各异的大鼠肠系膜微动脉分支区域血液流态为稳定层流;红细胞通过不规则变形能很好地适应血管腔不同的几何形态,以保持血液流态的稳定。结果表明,微小动脉血流方向的改变未能在分支区域导致湍流发生,小动脉端侧吻合只是人为增加了侧支循环,同样不会导致血流紊乱和增加血栓形成的危险 相似文献