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41.
血小板血浆对人牙髓细胞增殖的影响   总被引:3,自引:0,他引:3  
目的:观察血小板血浆及其细化成分对人牙髓细胞增殖的影响。方法:使用因正畸而拔除的人牙的牙髓细胞,用细胞定量测定试剂盒测定细胞增殖情况。结果:5%的多血小板血浆(platelet-rich plasma,PRP)、5%和10%的洗净血小板(washed platelet,WPLT)均明显地促进了人牙髓细胞的增殖,而且WPLT的作用较PRP更显著。乏血小板血浆(platelet-poor plasma,PPP)呈浓度依赖性地抑制了人牙髓细胞增殖,5%WPLT促进人牙髓细胞增殖的作用。结论:去除血浆成分的WPLT对培养的人牙髓细胞增殖有明显的促进作用;血浆中可能存在对抗血小板生长因子作用的因子。  相似文献   
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Abstract. As part of the FINMONICA project, serum total cholesterol (TC) and high density lipoprotein cholesterol (HDLC) concentrations were determined in 1216 AMI patients (937 men. 279 women) aged 35–64 years in the province of Kuopio in eastern Finland during the 5-year period 1983–87. The distributions were compared with the corresponding distributions in a representative sample of the general population of the same area (1026 men, 1021 women). The mean serum TC levels did not differ between the AMI patients and the normal population. Only the prevalence of a very high serum TC level (> 8.0 mmol l?1) among women was significantly higher in the AMI group than in the population sample. On the other hand, in both sexes the age-adjusted mean HDLC was significantly lower in the AMI group than in the population sample. Our findings emphasize the importance of HDLC measurement as a part of the assessment of the lipid risk factor profile in patients with AMI.  相似文献   
45.
Sequential Bilateral BBB During Dofetilide. Introduction: I in mechanism of wide QRS complex tachycardias during dofetilide infusion was studied in a patient with atrial fibrillation.
Methods and Results: Endocardial recording from the intraventricular conduction system showed that dofetilide caused "classic" aberrant conduction (Ashman phenomenon, typical QKS morphology) at high prematurity ratios (preceding interval = 1.78 X coupling interval 290), thus mimicking ventricular ectopy. In addition, there was frequent sequential bilateral bundle branch block, caused by a significant difference in preceding bundle-to-bundle intervals (mean difference ± 1 SD: 74 ± 26 msec).
Conclusion: The present findings may prove helpful in the clinical assessment of wide QKS complex rhythms after dofetilide and possibly other "pure" Class III antiarrhythmics.  相似文献   
46.
Abstract. Objectives . To examine, whether the acute myocardial infarctions (AMIs) are becoming smaller. Design . Analysis of electrocardiogram (ECG) and enzyme findings of community-based AMI registers in three geographical areas of Finland during the 8-year period 1983–90. Setting . In the FINMONICA AMI Register, all suspected coronary events in persons aged 25–64 years have been registered since 1983 according to the protocol of the WHO MONICA project in the provinces of North Karelia and Kuopio in eastern Finland and Turku/Loimaa area in south-western Finland. Subjects . Each consecutive case of suspected AMI originating from the monitored populations. During the study period, 11487 definite or possible AMIs were registered. Main outcome measures . Trends in ECG findings classified as definite or probable, and trends in enzyme findings classified as abnormal or equivocal. Results . Of the registered AMIs, 8439 (73.5%) reached the hospital alive and survived ≥ 24 h from the beginning of the symptoms. They were included in the analyses of this report and divided further, to first ever AMIs (n = 5392) and to recurrent AMIs (3047). During the study period, the proportion of ECG findings classified as definite on the basis of the serial Minnesota coding declined in men 3.1% year?1 (P < 0.0001) on average for first AMIs and 1.9% year?1 (P = 0.004) for recurrent AMIs. In women, the corresponding declines were 1.9% year?1 (P = 0.007) and 1.6% year?1 (P = 0.02), respectively. Also, the proportion of enzymes classified as abnormal declined amongst men 2.2% year (P < 0.0001) for first AMIs and 2.8% year?1 (P < 0.0001) for recurrent AMIs. In women, the corresponding declines for abnormal enzymes was 1.3% year?1 (P = 0.13) and 3.0% year?1 (P = 0.02). These findings were consistent in all three areas with different registration teams and different laboratories. The proportion of definite ECG findings amongst patients hospitalized for AMI declined almost by half and the proportion of abnormal enzyme findings declined almost by one-third during the study period. Conclusions . Our findings are compatible with the clinical observation that the hospitalized AMIs are becoming smaller. The timing and magnitude of the changes suggest that they are mainly caused by decreased risk-factor levels in the population. Improved treatment of coronary heart disease and changed hospital admission policy are likely to be contributing factors.  相似文献   
47.
Summary
  • ? This paper gives a brief review of existing research studies concerning patient information.
  • ? The paper outlines two relevant perspectives on information giving and on the meaning of information to the individual patient: ideological and practical.
  • ? From these two perspectives the knowledge structures of four patient groups: surgical patients, cancer patients, dialysis patients and psychiatric patients are looked at more closely.
  相似文献   
48.
Ohno  YI; Hirai  KI; Kanoh  T; Uchino  H; Ogawa  K 《Blood》1982,60(5):1195-1202
The ultrastructural H2O2-producing site in human polymorphonuclear leukocytes (PMN) stimulated with soluble stimuli was studied using a CeCl3-technique. CeLlular aggregation and formation of small vacuoles were observed when PMN were stimulated with 100 microgram/ml concanavalin-A, 1 mg/ml phytohemagglutinin, or 100 microgram/ml wheat germ agglutinin for 10 min at 37 degrees C. Electron-dense deposits formed from the reaction of H2O2 and CeCl3 were observed on the contact surface of the plasma membrane of aggregated PMN stimulated with lectins. Treatment with 5 microgram/ml cytochalasin-B before lectin- stimulation induced an enhanced formation of vacuoles, degranuLation, rounding of the contour, cellular aggregation, and enhancement of the deposits. Phorbol myristate acetate (PMA; 100 ng/ml) induced strong leukocyte aggregation, the formation of multiple huge vacuoles, degranulation, and H2O2 production at almost all of the contact surface between adjoining PMN and between PMN and erythrocytes, mononuclear cells, or thrombocytes. In PMN stimulated with digitonin (B microgram/ml), vacuolar formation, degranulation, multiple projections on the surface, and H2O2 production on the whole surface membrane were demonstrated. It is shown that cellular aggregation and cell-to-cell contact have an important role in the induction of O2- production induced by lectins or PMA and that O2- production induced by the detergent is not dependent on leukocyte aggregation.  相似文献   
49.
STATEMENT OF THE PROBLEM: Low levels of high-density lipoprotein cholesterol (HDL-C) have a strong association with coronary artery disease (CAD) in patients with non-insulin-dependent diabetes mellitus (NIDDM). In this study, we tried to evaluate whether one or both of the major HDL subclasses (HDL2, HDL3) is strongly associated with the risk of CAD in NIDDM subjects. METHODS: The separation of HDL subclasses was carried out by ultracentrifugation in a Beckman Airfuge. HDL2 subclass was isolated from the supernatant and its cholesterol content was measured enzymatically. Plasma HDL3 cholesterol was calculated as the difference between results for total HDL cholesterol and HDL2 cholesterol. RESULTS: NIDDM patients with CAD had significantly higher triglyceride levels compared to either control (217.09+/-55.04 versus 89.62+/-31.29 mg/dl, P=.001) or CAD patients without NIDDM (217.09+/-55.04 versus 156.28+/-46.39 mg/dl, P<.05). However, in the diabetic patients with CAD, there was a statistically significant decrease in HDL cholesterol (39.63+/-8.59 versus 55.86+/-13.49 mg/dl, P<.01), HDL2 cholesterol (8.74+/-3.28 versus 16.95+/-5.73 mg/dl, P<.001), and HDL3 cholesterol (31.23+/-7.41 versus 38.91+/-8.93 mg/dl, P<.05) in comparison to nondiabetic controls. Moreover, in the comparison between non-insulin-dependent diabetics with CAD and CAD subjects without NIDDM, HDL cholesterol (39.63+/-8.59 versus 46.13+/-6.33 mg/dl, P<.05) and HDL2 cholesterol (8.74+/-3.28 versus 11.84+/-4.01 mg/dl, P<.02) were significantly reduced, while HDL3 cholesterol levels were (31.23+/-7.41 versus 34.29+/-7.94 mg/dl, P=.92) unaltered. Additionally, the percentage reduction of cholesterol in HDL2 fraction was proportionately greater than the decrease in HDL3 subclass in both comparisons. Moreover, in NIDDM with CAD, HDL cholesterol was reduced by 29% and 14%, HDL2 cholesterol by 48% and 26%, and HDL3 cholesterol by 20% and 9%, compared relatively to controls and CAD subjects without NIDDM. CONCLUSIONS: In conclusion, HDL2 is the more variable subclass and reflects changes in HDL. This suggests that the protective role of total HDL against CAD is mainly mediated through HDL2 fraction. Therefore, HDL2 might be a better predictor of coronary heart disease than total HDL, in non-insulin-dependent diabetes mellitus.  相似文献   
50.
Mills  KI; MacKenzie  ED; Birnie  GD 《Blood》1988,72(4):1237-1241
The Philadelphia (Ph1) chromosome, characteristic of chronic myelogenous leukemia (CML), arises from a reciprocal translocation between chromosomes 9 and 22. The site of the breakpoint on chromosome 22 is within a small region called the breakpoint cluster region (bcr). We have mapped the breakpoint within the bcr in peripheral blood leukocyte DNA from 22 Ph1-positive CML patients. No correlation between the site of the breakpoint and the clinical phase of the disease was found. However, a striking correlation between the site of the breakpoint and the length of time between presentation and onset of acute phase was observed: on average, patients with a 5' break-point had a fourfold longer chronic phase (median, 203 weeks) than those with a 3' breakpoint (median, 52 weeks).  相似文献   
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