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1.
Abstract: The efficacy and safety of recombinant human erythropoietin (rhEPO) were tested when given subcutaneously (s.c.) in an escalating dose of 2000–10,000 units (U) daily in 60 patients with cancer-related anaemia (CRA). A positive response, defined as an increase in haemoglobin more than 2 g/dl and independence of blood transfusions, was observed in 23 of 48 evaluable patients (48%) within a median of 8 wk. In detail, rhEPO corrected anaemia in 11 of 14 patients (79%) with malignant lymphoma, in 8 of 15 patients (53%) with multiple myeloma and in 4 of 10 patients (40%) with a solid tumour. The median dose of rhEPO in successful cases was 5000 U daily. Four patients with agnogenic myeloid metaplasia and 5 with myelodysplastic disorder failed to respond to rhEPO. No patient had any severe side effects. Pretreatment serum erythropoietin levels appeared to be a weak predictor for response to rhEPO treatment. In conclusion, rhEPO seems to be safe and effective in correcting CRA in certain groups of patients.  相似文献   
2.
Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future.  相似文献   
3.
目的探讨舒利迭(吸入型肾上腺皮质激素与长效β2-受体激动剂的预混制剂)联合双水平气道正压通气(B iPAP)对稳定期慢性阻塞性肺疾病(COPD)的治疗作用。方法稳定期COPD病人52例,舒利迭TM50/250,1吸/次,2次/d;B iPAP,吸气压力(IPAP)10~20cm H2O,呼气压力(EPAP,也称PEEP)3~6cm H2O,吸氧浓度(FiO2)3L/m in,每天夜间通气6~8h。观察治疗前、治疗后12周病人临床症状、生活质量、健康状态和肺功能。结果治疗前、治疗后12周病人的临床症状、急性加重次数及严重程度、健康状态和生活质量、肺功能等指标比较差异有统计学意义(P<0.05)。结论舒利迭联合B iPAP治疗稳定期COPD病人能够明显改善其症状,提高生活质量,有一定的临床应用价值,对减缓COPD病人肺功能下降有积极意义。  相似文献   
4.
Background: Multiple factors related to specific dimensions of health – general, physical and mental – contribute to mortality in the elderly, but their relative contributions to mortality risk is not well‐known. The objectives of this prospective population‐based cohort study were to measure mortality rates and to identify predictors of mortality in community‐dwelling men and women aged 65 years or older in Korea by examining self assessments of general health, objective medical burden, and measurement of cognition, mood and function. Methods: A total of 1245 elderly (529 men; 716 women) were followed up longitudinally for 3.5 years. Fixed predictor variables observed at baseline examined in Cox proportional hazards models were age, sex, education, chronic medical illnesses, self‐rated health, basic activities of daily living, depression measured by the Geriatric Depression Scale, and cognition measured by the Mini‐Mental State Examination. Results: Mortality rates were similar to those of the 2001 Korean population. Older age, male sex, poor self‐rated health and presence of cerebrovascular disease were significant predictors of mortality. Presence of ischemic heart disease and cerebrovascular disease at baseline predicted mortality in men, but not in women. Depression predicted mortality only when chronic medical illnesses were excluded from the model. Conclusions: Subjective self‐rated health and objective medical burden are strong independent predictors of mortality in this elderly community population, in addition to age and sex.  相似文献   
5.
This study is a predictor analysis of the screening procedure followed by a psychiatric service for a period of 1 year preceding and a period of 1 year following the introduction of community psychiatry. Throughout this period, the psychiatric service consisted of a local service within the catchment area and a central service at a psychiatric hospital outside the area. At the time of the reorganization, the responsibility for the psychiatric service was transferred from the public health authorities to the social services. Before the reorganization, screenings were conducted on the basis of referral papers or simply as a result of telephone communication. After the reorganization, the screening procedure was intensified by means of a pre-examination. One aim of the reorganization was to ensure that the severely mentally ill take priority over patients characterized predominantly by social strain. Patients with manic-depressive psychosis and other psychoses showed a significantly increased probability of being accepted for treatment, whereas those with schizophrenia showed no significant increase, irrespective of the service reorganization. Similarly, manic-depressive psychosis and other psychoses (not schizophrenia) were significant predictors of hospitalization at the mental hospital outside the catchment area as well as hospitalization in the local facilities, irrespective of the service reorganization. Indicators of social strain were not given higher priority following the service reorganization.  相似文献   
6.
目的 探讨急性心肌梗死(AMI)溶栓治疗后无创法评价心肌再灌注的可行性。方法选择AMI溶栓治疗后行冠状动脉造影的患者,溶栓后90min血浆肌红蛋白(Mb)浓度与溶栓前血浆Mb浓度比值≥2.4或心电图ST段回落≥50%定义为成功再灌注(阳性)。上述两项指标均阳性为完全再灌注,仅一项阳性为部分再灌注,两项均阴性为无再灌注。再根据冠状动脉造影结果将患者分为完全再灌注(TIMI3级)、部分再灌注(TIMI2级)、无再灌注(TIMI0~1级)。对无创法和介入法进行一致性检验。共入选45例患者。结果无创法和介入法评价心肌再灌注经一致性检验,符合率为84.4%,Kappa=0.75(P〈0.01)。结论.心电图ST段回落和血浆Mb浓度变化两项指标合用可提高评价心肌再灌注准确性,和介入法有很高的符合率,简便易行,且结果可靠。  相似文献   
7.
Electrocardiographic imaging (ECGI) is a developing imaging modality for cardiac electrophysiology and arrhythmias. It reconstructs epicardial potentials, electrograms, and isochrones from electrocardiographic body-surface potentials noninvasively. Current ECGI methodology employs Tikhonov regularization, which imposes constraints on the reconstructed potentials or their derivatives. This approach can sometimes reduce spatial resolution by smoothing the solution. Accuracy depends on a priori knowledge of solution characteristics and determination of an optimal regularization parameter. These properties led us to implement an independent, iterative approach for ECGI—the generalized minimal residual (GMRes) method—which does not apply constraints. GMRes was applied to experimental data during activation/repolarization of normal and infarcted hearts. GMRes reconstructions were compared to Tikhonov reconstructions and to measured gold standards in isolated hearts. Overall, the accuracy of GMRes solutions was similar to Tikhonov regularization. However, in certain cases GMRes recovered localized potential features (e.g., multiple potential minima), which were lost in the Tikhonov solution. Simultaneous use of these two complementary methods in clinical ECGI will ensure reliability and maximal extraction of diagnostic information in the absence of a priori information about a patient's condition.© 2003 Biomedical Engineering Society. PAC2003: 8719Hh, 8757Gg  相似文献   
8.
Using a flexible piezoelectric film, the authors developed a simple system to determine noninvasively the heart rate of chicken embryos and hatchlings. The film was piezoelectric polyvinylidene fluoride (PVDF), which is sensitive enough to detect cardiogenic ballistic movements of the egg (ballistocardiogram (BCG)) and precordial movements of the hatchling attributable to cardiac contractions (apexcardiogram (ACG)). The BCG could be detected, during the second half of incubation, by placing the egg on the PVDF film on a soft substrate. The detected signal was found to be a measure of movement velocity. The ACG could be measured when the hatchling's chest wall made contact with the PVDF film installed in a box in which the hatchling was confined. The heart rate was counted from the lag time of autocorrelation calculated for a certain time segment (e.g. 2s) of the BCG and ACG recordings.  相似文献   
9.
Summary The reliability of noninvasive, automatic blood pressure monitoring is not yet clearly established. A 24-h ambulatory blood pressure profile was obtained in 9 healthy, normotensive subjects with an automatic, noninvasive device. The blood pressure profile showed the typical circadian pattern with lower systolic and diastolic values during sleep, although pulse pressure was fairly constant (about 40 mm Hg). The systolic blood pressure rose steeply in the early morning hours — before waking up. The results were compared with simultaneous hourly readings using the auscultatory method. There were no statistically significant differences between the automatic and auscultatory readings, 13 of the 18 mean values at. different time points being within 2 mm Hg of each other. All the auscultatory means fell within the 95% confidence limits of those measured hourly by the automatic method. Although the automatic method seemed to be reliable compared with the auscultatory method, its sensitivity to motion artifacts is a disadvantage in a truly ambulatory setting.  相似文献   
10.
Three different auditory stimulus paradigms were used to elicit P300 potentials. Normal subjects were tested on the classical rare target stimulus, single-stimulus and omitted-stimulus conditions. Noninvasive identification of the cerebral sources of the event-related potentials (ERPs) was performed using spatio-temporal multiple dipole modeling (BESA software) with individually sized spherical head models. The grand average data of each condition was first independently modeled and these models were used as starting values for modeling each individual subject's data. Models for the rare-stimulus condition and single-stimulus condition both consisted of 6 dipoles. Models for the omitted-stimulus condition consisted of 2 dipoles. The dipole locations of the final individual 6-dipole models for the rare and single-stimulus conditions did not differ significantly from each other or from one previous result obtained from a another group of subjects (Tarkka et al. 1995). Super-imposition of the dipole coordinates on the sterotaxic brain atlas suggests that bilateral deep medial temporal lobe structures are the major contributors to rare and single-stimulus P300s. Because both the wave form morphology and the source model of the P300 elicited by single stimulus were close to those of the rare-stimulus P300 it may be that the underlying neural mechanisms eliciting these P300 potentials are essentially the same.  相似文献   
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