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81.
C. J. Bowden W. D. Figg N. A. Dawson O. Sartor R. J. Bitton M. S. Weinberger Donna Headlee Eddie Reed C. E. Myers M. R. Cooper 《Cancer chemotherapy and pharmacology》1996,39(1-2):1-8
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis,
but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer,
with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken
to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations
(275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous
infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted
in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed
in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml
for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed
this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response
rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses
were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy
with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred
with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well
tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional
therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but
it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment
of suramin’s activity in hormone-refractory prostate cancer.
Received: 9 June 1995/Accepted: 18 March 1996 相似文献
82.
本文对我省56眼矿泉水的地理分布符合国家标准的情况及矿泉水水化学类型进行了统计分析,结果表明:56眼矿泉水基本遍布全省;其感官指标、污染物指标及微生物指标均符合国家标准;通过对限量指标分析,我省矿泉水属念锶或含偏硅酸或二者兼含;水化学分类以HCO3·Ca型居多,其次为HCO3-Ca·Na型。对影响卫生化学性能的决定因子进行相关分析表明:除Ca2+与Mg2+呈正相关外,K+与Na+及Sr与H2SiO3之间无相关性 相似文献
83.
S.J. Gallacher G. Thomson W.D. Fraser B.M. Fisher C.G. Gemmell A.C. MacCuish 《Diabetic medicine》1995,12(10):916-920
Neutrophil bactericidal activity was assessed in patients with type 1 (n=45) and Type 2 diabetes mellitus (n=68) and non-diabetic control subjects (n=40) by measurement of whole blood chemiluminescence. Though chemiluminescence values tended to be highest in the non-diabetic subjects these differences were not statistically significant (mean ± SD) (2.73 ± 1.65 mV (controls), 2.33 ± 1.41 mV (Type 1 diabetes) and 2.38 ± 1.12 mV (Type 2 diabetes), F=1.12, p=0.33). Significant negative correlations were evident, however, in patients with both Type 1 and Type 2 diabetes between chemiluminescence and glycated haemoglobin (rs=-0.35, p=0.005 (Type 1), rs=-0.45, p=0.002 (Type 2), fructosamine (rs=-0.36, p=0.003 (Type 1), rs=-0.42, p=0.004 (Type 2)), and random blood glucose (rs=-0.25, p=0.04 (Type 1), rs=-0.48, p=0.001 (Type 2)). Changes in whole blood chemiluminescence in a further group of 10 patients with Type 2 diabetes mellitus commenced on insulin therapy were followed for 21 days. Serum fructosamine concentrations fell significantly over this time (524 ± 58 μmol l?1 to 405 ± 47 μmol l?1, p<0.001), however, although chemiluminescence values tended to rise these changes were not statistically significant (1.01 ± 0.38 mV to 1.60 ± 0.91 mV, S=4.24, df=5, p=0.52). These results suggest that impaired neutrophil bactericidal function is associated with poor blood glucose control. While it is likely that neutrophil bactericidal function will improve as blood glucose control improves, further studies are required both to confirm this and to demonstrate a reduction in the incidence of clinical bacterial infection. 相似文献
84.
E. M. Robertson R. C. Miall 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(1):148-152
The human arm is kinematically redundant, which may allow flexibility in the execution of reaching movements. We have compared
reaching movements with and without kinematic redundancy to unpredictable double-step targets. Subjects sat in front of a
digitising tablet and were able to view an arc of four targets reflected in the mirror as virtual images in the plane of the
tablet. They were instructed to move, from a central starting point, in as straight a line as possible to a target. In one-third
of trials, the target light switched to one of its neighbours during the movement. Subjects made 60 movements using shoulder,
elbow and wrist and then another 60 movements in which only shoulder and elbow movement were allowed. By restraining the wrist,
the limb was made non-redundant. The path length was calculated for each movement. In single-step trials, there was no significant
difference between path lengths performed with and without wrist restraint. As expected there was a significant increase in
path length during double-step trials. Moreover this increase was significantly greater when the wrist was restrained. The
variability across both single- and double-step movements was significantly less while the wrist was restrained. Importantly
the performance time of the movements did not alter significantly for single-step, double-step or restrained movements. These
results suggest that the nervous system exploits the intrinsic redundancy of the limb when controlling voluntary movements
and is therefore more effective at reprogramming movements to double-step targets.
Received: 24 March 1997 / Accepted: 7 July 1997 相似文献
85.
Bronwyn A. Kingwell Lisa Krause Stevo Julius 《Clinical and experimental pharmacology & physiology》1994,21(1):31-39
1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator. 相似文献
86.
五所医院特需医疗服务状况调查 总被引:1,自引:1,他引:0
通过对上海医科大学附属华山医院、协和医院、北京同仁医院、中山医科大学附属第一医院、浙江医科大学附属第二医院开展的特需医疗服务情况的调查,论述了五所医院的具体做法,在对调查结果进行分析的基础上,就特需医疗服务的管理提出了建议。 相似文献
87.
PAUL CHRISTINE L.; SANSON-FISHER ROBERT W.; REDMAN SELINA; CARTER SUSAN 《Health promotion international》1994,9(4):241-248
Accidental injury in the home is a major cause of death andill-health among young children. Reducing home safety hazardsby the use of safety devices such as stair barriers and safetytaps has the potential to prevent home injuries. Little is knownabout levels of home safety hazards or how to encourage parentsto reduce hazards. The Safe Place Project examined parents'knowledge of home safety and the prevalence of safety hazardsin homes where there were young children. The study also evaluatedthe effectiveness of a low-cost strategy aimed at reducing homesafety hazards. The strategy used trained volunteers to providehome safety checks and tailored safety education in conjunctionwith increasing the availability of home safety devices. Onehundred and six families with young children participated inthe project. Some homes contained many hazards, with 43% ofthe sample having more than 10 home safety hazards. At follow-up,the intervention group showed a significant reduction in homehazards and a trend towards an increase in knowledge of homesafety. 相似文献
88.
Andrea Nardini Carlo Piccardi Rodolfo Soncini-Sessa 《Optimal control applications & methods.》1994,15(1):1-12
A suboptimal controller for a class of discrete-time systems is presented. The controller is derived by first solving ‘off-line’ a simplified optimal control problem obtained by neglecting part of the system state and by considering a larger time step, then by solving ‘on-line’ at each time step an optimization problem based on the results of the previously solved ‘off-line’ problem. A simple numerical example is presented to illustrate the control scheme. 相似文献
89.
运用人力资源管理策略 改革病房护理管理 总被引:3,自引:0,他引:3
从发展成功管理的共同文化,创建优质服务病房;建立有效的护理人力资源管理支持系统,创建适合于专业护理的工作环境,确保护理质量;以病人为中心,以病人满意度作为衡量护理工作优劣的标准三个方面介绍了乐山市人民医院运用护理人力资源管理策略,改革病房护理管理,创建优质服务病房的实践经验及其效果。 相似文献
90.
Symptom Clusters in Patients With High-Grade Glioma 总被引:2,自引:0,他引:2