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61.
Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content. 相似文献
62.
胃粘膜内pH值测定在危重病人中的预警价值 总被引:3,自引:0,他引:3
目的 :观察在危重病患者中反映组织水平氧代谢的胃粘膜内 p Hi,与反映全身氧代谢的指标间的关系以及胃粘膜内p Hi的预警价值。方法 :用胃张力计测定危重病患者入科即刻及治疗 2 4h后胃粘膜内 p Hi,并测定 p Ha ,Pa O2 / Fi O2 ,行 APACHE 评分。结果 :死亡组入科即刻 p Hi( 7.13 3± 0 .3 74)较存活组 ( 7.3 89± 0 .0 62 )显著降低 ( P<0 .0 1) ,治疗 2 4小时后胃粘膜内 p Hi死亡组( 6.911± 0 .496)较存活组 ( 7.43 4± 0 .0 5 1)降低更显著 ( P<0 .0 0 1) ;入科即刻 p Hi≤ 7.3 2的患者病死率为 75 .0 %,治疗 2 4h后胃粘膜内 p Hi≤ 7.3 2的患者病死率为 88.9%。结论 :作为局部组织氧合指标的 p Hi在常规的全身氧代谢指标未改变之前就发生了明显的变化 ;p Hi的降低与病死率有明显的相关性。 相似文献
63.
目的:利用间接指标的方法,观察急性心肌梗塞(AMI)后心肌再灌注损伤(MyocardialReperfusionInjury,MRI)的临床表现,了解MRI对左室射血功能及梗塞后心绞痛的影响。方法:对尿激酶静脉溶栓后32例冠脉再通者和10例冠脉未再通者进行心电图和心肌酶学动态监测,AMI后3周所有患者接受心脏彩超检查。结果:临床判断冠脉再通者中MRI发生率为5625%(18/32),心电图主要表现为突发短暂性ST段明显抬高,其次是再灌注心律失常,束支或房室传导阻滞最少见。MRI时血清CPK峰值时间为1386±426小时,较冠脉再通而无MRI组1917±536小时显著前移(P<005)。MRI组LVEF(4525±1077%)显著高于冠脉未再通组(3860±925%)(P<005),但与无MRI组(5328±1277%)相比,P>005。MRI组梗塞后心绞痛发生率为2728%,与无MRI组4280%和冠脉未再通组1000%相比,P均>005。结论:AMI静脉溶栓后部分患者发生再灌注损伤,MRI对LVEF和梗塞后心绞痛发作无显著影响。 相似文献
64.
David Pye Peter Herse Ha Nguyen Lan Vuong Quoc Pham 《Clinical & experimental optometry》1999,82(1):11-13
Background : Clinical experience has shown that the sensitivity indices reported by the Humphrey Field Analyser (HFA) are generally higher than those given by the Medmont Automated Perimeter (M600). It is the purpose of this paper to determine a conversion factor for the two perimeters and to confirm this prediction using clinical data. Theory predicted that HFAsensitivity ? 5 dB = M600sensitivity. Methods : Sensitivity versus eccentricity profiles were measured over the central visual field on 10 young subjects using both perimeters. Results : Both the HFA and the M600 operate within the realms of the Weber law and measure similar Weber fractions. The sensitivity profiles had similar slopes (about ?0.2 dB/degree) and were separated by about six decibels with the HFA reporting higher sensitivity values. This result confirmed the theoretical prediction. Conclusion : The difference in threshold sensitivities between the two perimeters is a result of differences in scaling factors and instrument luminances. A suggested clinical conversion factor is to subtract 5 dB from the HFA data to approximate those of the M600. 相似文献
65.
Purpose. The human plasma binding of cyclosporin A was studied in vitro using the technique of microdialysis. The effect of temperature on the overall binding interaction between cyclosporin A and human plasma was also investigated.
Methods. Flow-through loop-type microdialysis probes were constructed from fused silica tubing and regenerated cellulose tubing with a MWCO of 13000 daltons. Probes were perfused with phosphate buffer (0.5 µl/min) and the concentration of 3H-cyclosporin A in the well-mixed medium (plasma or buffer) was 1200 ng/ml. Relative recoveries of cyclosporin A from plasma or buffer were determined for each probe by separate experiments to measure the solute gain or loss with reference to the perfusate.
Results. Recoveries determined by loss were significantly greater than those determined by gain and in each case temperature dependent, with higher recoveries at higher temperatures. The plasma free fraction of cyclosporin A calculated from the recovery data and the perfusate to plasma concentration ratios was dependent on temperature in a log-linear fashion. Mean ± s.d. plasma free fractions expressed in percent were 33.5 ± 4.6, 17.9 ± 3.6, 6.2 ± 0.8, 3.0 ± 0.6, and 1.5 ± 0.2 at temperatures of 4, 10, 20, 30, and 37°C, respectively. Assuming that the enthalpy of binding is constant over the temperature range studied and pseudo-first order conditions exist, the binding reaction at these temperatures was spontaneous, endothermic (H = 74.0 kJ/mole), and entropically driven (S = 0.274 kJ/mole/deg).
Conclusions. These results show that the free fraction of cyclosporin A in human plasma is dependent on temperature with the fraction unbound decreasing with temperature in the range of 4 to 37°C. The thermodynamic parameters for the binding of cyclosporin A to plasma components indicate that the reaction is a spontaneous endothermic reaction that is mainly entropy driven, similar to the partitioning of lipophilic molecules from an aqueous to a hydrophobic phase. Moreover, these results show that microdialysis is a feasible method to determine the binding interactions between plasma and cyclosporin A, which indicates the method may be suitable for other difficult binding studies where the solutes have nonspecific binding to separation devices. 相似文献
66.
TRAINA M.; ROTOLO A.; RAINERI M.; TRAPANI R.; CANDELA B.; RAINERI A. A. 《European heart journal》1993,14(8):1034-1039
Several controlled trials on the thrombolytic treatment of acutemyocardial infarction (AMI) have failed to demonstrate thatthrombolysis has a simultaneous positive effect on left ventricularfunction and survival. One explanation may be that spontaneouschanges in left ventricular function occurred during the progressionof AMI in control patients. The aim of this study was to evaluatethe spontaneous evolution of left ventricular ejection fraction(LVEF) and its prognostic influence on early (1 month) and late(1 year) mortality in patients with AMI. We studied 216 patientsadmitted to our CCU within 24 h of the onset of symptoms. LVEFwas determined by radionuclide ventriculography on admission(RNV1) and at the end of the necrotic phase (RNV2). Fourteenpatients died before RNV2. On the basis of LVEF values at RNV1,the remaining 202 patients were divided into two groups: thosewith a normal LVEF (55%), and those with an abnormal LVEF (<55%). Among patients with a normal LVEF at RNV1 (64 patients) a significantincrease (>12%) in LVEF at RNV2 was observed in 12.5%, asignificant decrease (>12%) in 12.5% and no change at allin 75%. All of these patients survived, regardless of the evolutionof LVEF. In patients with an abnormal LVEF at RNV1 (138) a significantincrease (>5%) in LVEF at RNV2 was observed in 72.5%, a significantdecrease (>5%) in 6.5% and no change at all in 21%. In patientswith a LVEF increase, both early and late mortality were significantlylower than in patients with a LVEF decrease: (early mortality4% vs 55.5%, P<0.001; late mortality 6% vs 66.6%, P<0.001)respectively. In patients without any LVEF change, mortalitywas significantly lower than in patients with a LVEF decrease:(early mortality 10% vs 55.5%, P = 0.01; late mortality 14%vs 66.6%, P=0.004) respectively. In conclusion, our data demonstrate that a significant increasein LVEF occurs in most patients with an early depression ofleft ventricular function. This behaviour is associated witha low early and late mortality in comparison with the patientswith a LVEF decrease and is independent of thrombolytic treatment.When the early measurement of LVEF is normal the prognosis isnot influenced by LVEF evolution. These findings must be keptin mind when LVEF is used as a prognostic index and as an end-pointfor the evaluation of the effects of thrombolytic therapy. 相似文献
67.
F. Scopinaro M. Banci A. Vania R. Tavolaro O. Schillaci A. Tisei B. Werner G. Digilio F. Ventriglia V. Colloridi 《European journal of nuclear medicine and molecular imaging》1993,20(7):603-608
Twenty-five thalassaemic patients treated with repeated blood transfusion (BT) and intensive iron removal therapy were studied by echocardiography and rest/stress equilibrium gated radionuclide angiocardiography (EGNA). Stress left ventricular ejection fraction (LVEF) showed an important negative correlation with number of BTs (r = –0.75). Abnormal values of stress LVEF were measured after 200 BTs: these data demonstrate the effectiveness of stress LVEF in the follow-up of patients who have undergone repeated BTs and the clinical importance of intensive chelation therapy. Peak filling rate did not show diagnostic value in the early detection of iron cardiotoxicity. However, its inverse correlation with BT (r = –60) indicates that iron overload depresses the diastolic parameters. 相似文献
68.
Sven-Börje Ewers Robyn Attewell Bo Baldetorp Åke Borg Eva Långström Dick Killander 《Breast cancer research and treatment》1991,20(2):93-108
In a prospective study of a consecutive breast cancer series accumulated in the period 1978–82, the S-phase fraction (SPF) and ploidy status were determined by flow cytometry performed on cell nuclei derived from samples of 580 primary tumors. Sixty percent of the tumors were non-diploid. After correction for debris the median SPF values were 7.3% overall, 12% for non-diploid tumors, and 2.9% for diploid tumors (2.6% when nodal subsets N2 and N3 and cases with metastases at presentation were excluded). The SPF values correlated both to tumor size (p=0.008) and to the number of positive axillary lymph nodes (p=0.03).At clinical follow-up in 1986, 467 unilateral breast cancer patients who had undergone radical treatment for cure could be evaluated with respect to the prognostic value of both the SPF value and ploidy status. The median duration of follow-up was then 59 months (range 2–90), and the median time-to-recurrence 24 months (range 2–69, n=137).At follow-up in 1991, 201/467 of the patients had died, the median duration of follow-up being 50 months (range 2–126) for the deceased, and 119 (range 6–148) for the survivors. In multivariate analysis (Cox's proportional hazards models), the strongest independent predictors of distant recurrence-free survival (DRFS) were the number of positive axillary lymph nodes (p<0.0001), the debris-corrected SPF value alone (p=0.003,versus p=0.05 for uncorrected value), and ploidy status combined with the corrected SPF value (p=0.0002). When age was taken into account, both the corrected SPF value and the ploidy-SPF combination were predictors of crude survival (p=0.006 and p=0.002, respectively).In univariate life-table analysis, the 5-year DRFS rate was 93% in node-negative (N0) cases with an SPF<7.3%, as compared to 80% in those with an SPF7.3% (p=0.005). Among node-positive cases, the prognostic value of the SPF was confined to those with 1–3 positive nodes, the 5-year DRFS rate being 68% in cases with an SPF<7.3%, as compared to 40% in cases with an SPF7.3% (p=0.01).Ploidy status and SPF were combined to form four groups: diploid & SPF<2.6% (DL), diploid & SPF2.6% (DH), non-diploid & SPF<12% (NDL), and non-diploid & SPF12% (NDH). Among node-negative patients, the DRFS rate fell from 95% in the DL group to 87% in the NDL group, with the DH group at an intermediate level, as compared with 74% (p=0.03) for the NDH group which accounted for the bulk of the early distant recurrences. Among patients with 1–3 positive lymph nodes, the 5-year DRFS rate was 68% in both the groups with low SPF values (DL and NDL), as compared with 45% in the DH group (p=0.03), and 37% in the NDH group (p=0.006).In this study, the flow cytometry SPF value, alone or in combination with ploidy status, yielded the most profound additional prognostic information, enabling both node-negative patients with a high probability of cure and patients at risk of early relapse to be identified. Among node-positive patients, the prognostic value of the SPF value was confined to those with 1–3 positive axillary lymph nodes (the predominant node-positive subgroup), enabling a high and a low DRFS rate subgroup to be distinguished – a useful distinction where selection for adjuvant drug treatment is concerned. As the predictive strength of the SPF value was enhanced when correction was made for debris, we would recommend that the effect of such factors as debris be minimized as far as possible when flow cytometry-derived SPF values are to be used for prognostic purposes. 相似文献
69.
板蓝根抑菌抗炎活性部位的评价 总被引:27,自引:0,他引:27
目的:评价和比较板蓝根5个化学部位抑菌、抗炎活性的强弱。方法:采用管碟法测定板蓝根不同化学部位对于金黄色葡萄球菌、铜绿假单胞菌的敏感性,观察对二甲苯所致小鼠耳廓肿胀的抑制作用。结果:板蓝根Ⅴ部位体外抑菌活性最强,Ⅴ部位具有显著的抗炎活性。结论:板蓝根中高极性成分具有很强的药理活性,是其发挥清热解毒功效的物质基础。 相似文献
70.