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1.
Psychometric data are presented which examine the validity of using the concentration of benzoylecgonine in urine, a major metabolite of cocaine, as a measure of drug use, in studies of drug abuse treatments. In such research the standard biological indicator of drug use is usually a qualitative urine drug test, which merely indicates the presence or absence of a drug or its metabolite. A quantitative (i.e. continuous) outcome measure, such as the concentration of a drug or its metabolite in a biological fluid, has substantially more statistical power than a dichotomous measure and should, therefore, prove a more sensitive measure of drug use when viewed from a measurement perspective. Data from two placebo-controlled clinical trials of fluoxetine as an adjunct to treatment for cocaine abuse are analyzed to address this issue. Results indicate that urine benzoylecgonine level is closely related to self-reports of drug use and is independent of levels of anxiety, depression and hopelessness.  相似文献   
2.
医院中团队建设涉及到医生、护士、医技等,但是并不是把这些人简单组合在一起就可以称为团队。除了团队组建的目标外,还包括团队里每个人明晰的责任义务、团队领导、对团队成果的考评以及团队所处的外在文化环境,只有综合上面各方因素,才能谈得上是团队建设,才能充分发挥团队优势,实现1+1>2的简单道理。法律、规章以及专业分类在加拿大,现存的法律、制度结构与他们对卫生保健专业定义的范围不一致。这一弊端妨碍了从业者潜能的最大发挥,这也意味着卫生保健行业中的人力资源并没有被充分利用。此外,除了法律以及规章制度方面的影响因素,专业…  相似文献   
3.
Computer-Assisted Design of an Implantable, Intrathoracic Artificial Lung   总被引:3,自引:0,他引:3  
Abstract: A semiempirical mathematical model of convective oxygen transport is used to design a new, low pressure loss, implantable artificial lung that could be used as a bridge to lung transplantation in patients with advanced respiratory failure. The mass transfer and flow friction relations pertinent to the design of a cross–flow hollow fiber membrane lung are described. The artificial lung is designed to transfer over 200 ml/min of oxygen at blood flow rates up to 5 L/min. A compact design and a blood-side pressure loss of <15 mm Hg allows the device to be implanted in the left chest without the need for a prosthetic blood pump. Surgical implantation of the artificial lung would require the creation of inflow and outflow anastomoses. Oxygen would be supplied via an external source. Blood properties, operating conditions, and empirically determined mass transfer and flow properties are all specified and input into a computer program that numerically solves the design equations. Computer–generated values for the device frontal area, blood path length, and fiber surface area are thereby obtained. The use of this computer–assisted design minimizes the need for extensive trial–and–error testing of prototype devices. Results from in vitro tests of a prototype implantable lung indicate that the mathematical model we describe is an accurate and useful tool in the design of hollow fiber artificial lungs.  相似文献   
4.
The current treatment of choice for chronic tympanic membrane perforations is surgery. Recent studies using various polypeptide growth factors to accelerate closure of tympanic membrane perforations in model systems have produced mixed results. This study evaluates the effect of acidic fibroblast growth factor (AFGF) and live yeast cell derivative (LYCD) on the rate of healing of acute tympanic membrane perforations in a rat model. Thirty-seven rats had both ears separately randomized in a blinded fashion to receive AFGF in one of three concentrations, LYCD, or a control solution. The rats initially underwent subtotal removal of the tympanic membranes bilaterally. Solutions were applied to the randomized ears daily for 3 days, starting at the time of the surgical perforation. The ears were photographed every 3 to 8 days for 35 days. The photographs were digitally scanned and a computer analysis was used to calculate the percentage of residual perforation. No significant difference in the rate of healing was observed for ears treated with AFGF or LYCD versus the controls. Given the potential advantages of medical treatment of tympanic membrane perforations and the established efficacy of growth factors in other model systems, however, further research is warranted. (Otolaryngol Head Neck Surg 1997;117:616-21.)  相似文献   
5.
本刊上期刊登该文章的第一部分.并引起很多读者的共鸣; 医院管理无大事.也无小事;因为医院运营的系统是通过纷繁复杂的各个子系统组成. 医院只有解决每个子系统中的各个问题.才能保证医院稳健的发展![编者按]  相似文献   
6.
7.
Atriofascicular Ablation During Fibrillation. Introduction: A male patient with an atriofascicular pathway underwent catheter ablation of the atriofascicular pathway during atrial fibrillation.
Methods and Results: The patient had preexcited atrial fibrillation both clinically and repeatedly during electrophysioiogic study. A preexcited tachycardia with a 1:1 AV relationship and regular RR intervals was also induced. Catheter ablation of the atriofascicular pathway could only be performed during persistent atrial fibrillation, based on mapping of the pathway's insertion into the right bundle branch. Following successful ablation and cardioversion to sinus rhythm, a regular QRS tachycardia (atrioventricular [AV] nodal reentry) having (he same rate, atrial activation sequence, and His-atrial time as the regular preexcited tachycardia noted preablation was initiated. An AV nodal slow pathway modification eliminated this tachycardia. Neither atrial fibrillation nor AV nodal reentry has recurred on follow-up.
Conclusion: This is the first report of atriofascicular mapping and ablation performed exclusively during atrial fibrillation and illustrates the utility of mapping the pathway's ventricular insertion. Other unusual features ("bystander" pathway activation during AV nodal reentry, possible role of the pathway in genesis of atrial fibrillation) are discussed.  相似文献   
8.
The neurotoxic effects of single subcutaneous injections of1000 mg triphenyl phosphite (TPP)/kg body weight were investigatedin White Leghorn hens. At 7 days postexposure, birds began toshow signs of mild to moderate ataxia that progressed to severeataxia and paralysis at 21 days. Inhibition of whole brain neuropathytarget esterase was 85% at 48 hr and 73% by 21 days postexposure.After postexposure periods of 7, 14, and 21 days, hens werekilled and their brains and spinal cords were examined for degeneratingaxons and terminals using the Fink-Heimer silver impregnationmethod. A small amount of degeneration was noted at 7 days.By 21 days, dense degeneration was noted in the spinal graymatter and funiculi. Degeneration was also present in the granularcell layer of cerebellar folia I-VI and in nuclei and fibertracts of the medulla. Moderate to dense degeneration was alsoseen in several forebrain and midbrain areas including the paleostriatum,ansa lenticularis, the dorsointermediate thalamic nucleus, lateralspiriform, pedunculopontine tegmental, and lateral mesencephalicnuclei and in the deeper layers of the optic tectum. These resultsindicate that, in addition to affecting the spinal cord andbrainstem, exposure to TPP also damages higher order centersresponsible for processing and integrating sensorimotor, visual,and auditory information.  相似文献   
9.
The locations of the three disulfide bonds of eclosion hormone (EH) isolated from Manduca sexta were assigned by sequence analysis of thermolysin fragments and by comparison of a key heterodimeric fragment to regiospecifically synthesized parallel and antiparallel isomers. We elucidated the complete structure of Manduca EH as a 62-residue peptide which has three disulfide bonds between Cys14-Cys38, Cys18-Cys34, and Cys21-Cys49.  相似文献   
10.
Summary We report our experience of the treatment of carcinoma in situ (CIS) using intravesical therapy with the Danish Bacillus Calmette-Guérin (BCG) strain 331 (SSI). Forty-two patients received treatment, 11 had primary and 31 secondary CIS. The median follow-up period was 26 months (range 3–68). Patients received 6 weekly instillations (1 course) and non-responders an additional 6 instillations at 2-week intervals (2 courses). The complete response rate was 59% for 1 -course patients, 33% for the 2-course patients and 68% for the entire series. Patients were considered treatment failures if they suffered progression to invasive cancer, metastasis or died from transitional cell carcinoma. BCG treatment was more effective in primary than in secondary CIS, with a complete response rate of 80% versus 65% and with no failures versus 35%. Patients with persistent CIS after the first course of BCG had a greater risk of failure than responders: 50% versus 17%. Patients with persistent CIS after the second course had a 75% failure rate. This suggests that cystectomy should be considered for non-responders following a 6-week course and recommended to those not responding to 2 courses. Ten patients had CIS in the prostatic urethra. All responded to BCG treatment; 2 suffered from recurrent CIS 1 associated with invasive urethral tumour. The incidence and severity of side effects were similar to those reported with other strains of BCG. One patient with primary CIS failed to complete the treatment owing to “BCG-itis”.  相似文献   
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