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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   
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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   
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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   
6.
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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A symposium entitled Impact of Nutrients on Cellular Lipid Peroxidationand Antioxidant Defense System was held at the 33rd Annual Meetingof the Society of Toxicology (SOT) at the Loews Anatole Hotelin Dallas, Texas. The symposium was sponsored by the Food SafetySpecialty Section and focused on the role of particular nutrientsin cellular lipid peroxidation and antioxidant defense system.Emphasis was placed on defining underlying mechanisms for damageand protection, as well as potential ramification in human healthissues. The following are extractions of some of the highlightsfrom each presentation.  相似文献   
10.
Previous reports demonstrated that repeated administration ofperoxisome proliferators protects against acetaminophen (APAP)hepatotoxicity in mice. This protection was associated witha decrease in APAP's selective protein arylation and glutathionedepletion. This study was conducted to determine if a singledose of clofibrate (CFB), rather than repeated doses, wouldsimilarly prevent APAP toxicity. CD-1 male mice received a singledose of 500 mg CFB/kg and controls were given corn oil 24 hrprior to APAP challenge. After an 18-hr fast, mice were challengedwith 800 mg APAP/kg (in 50% propylene glycol) and killed at4 or 12 hr. Other mice similarly pretreated were killed withoutAPAP challenge. The results showed that pretreatment with asingle CFB dose significantly decreased APAP-induced hepatotoxicity.At 12 hr after APAP plasma sorbitol dehydrogenase activity andthe severity of hepatocellular necrosis were decreased in CFBpretreated mice. Surprisingly, no differences in hepatic nonproteinsulfhydryl (NPSH) depletion or selective arylation of targetproteins in cytosol were observed at 4 hr after APAP challenge.Neither did a single dose of CFB significantly alter hepaticNPSH content prior to APAP challenge. These results indicatethat protection against APAP hepatotoxicity by CFB does notrequire repeated administration, and the absence of significantalterations in APAP's selective protein arylation or glutathionedepletion suggests that the protection against APAP hepatotoxicityafter a single treatment with CFB may differ mechanisticallyfrom the protection observed after repeted CFB dosing.  相似文献   
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