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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   
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OBJECTIVE: Several recent studies have reported high rates of sexual risk-taking and HIV infection among young men who have sex with men (MSM). Most of these studies used samples of convenience. The authors obtained population-based data on young MSM living in South Beach (Miami Beach, Florida), a resort community where some of the highest AIDS rates in the United States have been reported. METHODS: A household probability sample was drawn to survey unmarried 18- to 29-year-old MSM living in South Beach. Subjects were interviewed, completed self-administered questionnaires, and provided oral specimens for HIV antibody testing. RESULTS: From the 2,622 screened residential units, 100 mostly white and Hispanic MSM (92.6% of eligible participants) were enrolled in the study. Fifteen percent of the sample tested positive for antibodies to HIV. White and Hispanic MSM had similar rates. Forty-five percent of the sample reported engaging in unprotected anal intercourse (UAI) in the prior 12 months, and 31% reported UAI with a nonprimary partner. The estimated annual incidence of HIV infection was 6.3%. CONCLUSION: The high prevalences of UAI and HIV infection in South Beach attest to a previously undocumented public health concern. The extremely high estimated incidence for young MSM in South Beach highlights the urgent need for more effective risk-reduction interventions and further epidemiological research on resort areas.  相似文献   
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The Association of American Medical Colleges publishes an enormous database each year, which encompasses every conceivable category of medical education. This information covers high-school student premedical activities, medical school/student data, demographics of residents and fellows in training, a profile of medical school faculty according to academic rank and the enrollment of each medical school in the country. It is all categorized according to race, ethnicity and gender. Furthermore, it is a longitudinal survey and, therefore, valid comparisons can be made over long periods of time. The extensive coverage of African-American involvement in the system at all levels allows for healthcare planners, administrators, politicians and students/parents at all levels to use this as a roadmap for planning purposes. Much of the data is broken down according to individual states, thus enabling students to make better decisions about selecting private versus public institutions for their training. The data on residents in training and medical school faculty provides very useful information for healthcare planners, state and federal government officials, and medical school deans and university administrators interested in addressing diversity issues within their respective domains.  相似文献   
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Background: A previous study of piglet lung growth (Mansell et. al. 1989. J. Appl. Physiol., 67:1422–1427) showed transient stiffness to changes in shape and volume immediately after birth. Later, elastic recoil was found to increase as the lung grew in weight and volume. The present study uses morphometry to test possible structural correlates of these two mechanical changes. Methods: Piglet lungs were fixed near full inflation via the airways during the immediate newborn period (6–12 hours, n=3), at 3–5 days (n=6), 25–30 days (n=5), and 80–85 days (n=3). Morphometry comprised arithmetic and harmonic mean thicknesses of alveolar septae and average mean surface curvature. Measurements of curvature and airspace volume were combined to differentiate alveolar expansion from septal proliferation as mechanisms for volumetric growth. Results: The unique mechanical behavior of the newborn lungs was associated with relatively thick alveolar septae. Marked thinning of the septae and resolution of the stiffness to shape and volume change had occurred by 3–5 days. An increase in elastic recoil during the first postnatal month was found to be associated with simple airspace expansion. The second and third months were characterized by septal proliferation and increase in arithmetic mean septal thickness but elastic recoil did not increase further. Harmonic mean septal thickness and airspace volume per gram of lung tissue did not change over the course of the study. Conclusions: 1) A relative stiffness to shape and volume change in freshly newborn piglet lung is associated with relatively thick alveolar septal walls; 2) postnatal development of piglet lung parenchyma involves septal lengthening and thinning followed by septal proliferation; 3) the initial phase of septal lengthening, rather than the later phase of septal proliferation, is associated with increase in parenchymal recoil. © 1995 Wiley-Liss, Inc.  相似文献   
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BackgroundThe use of robotic-assisted total knee arthroplasty (TKA) has significantly increased over the past decade. Internet content is largely unregulated and may contain inaccurate and/or misleading information about robotic TKA. Our goal was to assess the content, quality, and readability of online material regarding robotic-assisted TKA.MethodsWe conducted an internet search for the top 50 web sites from each of the 3 most popular search engines (Google, Yahoo, and Bing) using the search term robotic total knee replacement. Each web site was assessed for content, quality, and readability. Web site quality was assessed utilizing the QUality Evaluation Scoring Tool (QUEST). Readability was assessed utilizing the Simple Measure of Gobbledygook, Flesch-Kincaid Grade Level, and Flesch Reading Ease Formula scores.ResultsGeneral risks of TKA were discussed in 47.2%, while benefits were discussed in 98.6% of all web sites. Inaccurate claims occurred at a significantly higher rate in physician/community hospital sources compared to university/academic web sites (59% vs 28%, P = .045). Web sites from university/academic web sites had the highest QUEST scores, while physician/community hospital sources scored the lowest (16.1 vs 10.6, P = .01). Most web sites were written at a college reading level or higher.ConclusionPatients should be counseled on the largely unregulated nature of online information regarding robotic-assisted TKA. Physicians and hospitals should consider revising the readability of their online information to a more appropriate level in order to provide accurate, evidence-based information to allow the patient to make an informed consent decision.  相似文献   
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BackgroundThe long-term safety results of the REALIZE (Ethicon Endo-Surgery, Inc., Cincinnati, OH) adjustable gastric band collected in this prospective, multicenter study in patients with morbid obesity are presented.ObjectivesTo determine the reoperation rate, including band revisions, replacements, and explants, resulting from a serious adverse device-related event through years 4 and 5. Various efficacy measures were also assessed as secondary objectives.SettingNine academic and/or private institutions.MethodsThe participating institutions enrolled 303 patients, who were then assessed on an annual basis, with 231 patients completing 5 years of follow-up. The study parameters included reoperation rates, changes in percentage of excess weight loss (%EWL), and changes in body mass index (BMI), as well as parameters of diabetes and dyslipidemia. Quality of life was assessed using the Short Form (SF)-36 and the Impact of Weight on Quality of Life-Lite questionnaires.ResultsThe reoperation rate due to a serious adverse event in this population at 5 years after implantation with the REALIZE gastric band was 8.9%. The most common serious adverse event was band slippage, which affected 6.9% of the study population. The mean %EWL was 35.6% ± 26.84%, and the decrease in mean BMI was ?7.01 ± 5.45 kg/m2 at 5 years. Patients experienced improvements in mean glycated hemoglobin and serum lipid levels, in addition to improvements in the quality of life measures.ConclusionNo new safety concerns were identified during the 5 years of follow-up. Although the results of this study did not meet the predefined safety criteria of 8% or less, the safety profile and long-term effectiveness observed in this study are consistent with those in the current literature.  相似文献   
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BackgroundWhile anti-vaccine messages on social media have been studied for content, reach, and effectiveness, less is known about those who create and promote the messages. Online influencers, or ‘everyday people who are influential within their online social networks’, are viewed as trusted voices who are often making similar life decisions as their followers. Therefore, their experiences with and perspectives on health issues can be persuasive.MethodsWe collaborated with a formal network of online influencers to interview, using a semi-structured interview guide, vaccine hesitant influencer mothers about their views on vaccination; their process for developing health-related social media content; their motivation to promote anti-vaccine messages; and their opinions on current vaccination messaging. Prescreening ensured a diverse sample by race/ethnicity, age, education, number of children, and geographic residence. Interviews occurred by telephone, were audio recorded, and transcribed. Themes were generated independently by two coders using a deductive coding approach.ResultsWe interviewed 15 online influencer mothers from across the U.S. (average age 39 years old; all married; 13 Caucasian, 1 African American, 1 Hispanic). In some capacity, 5 of the 15 wrote about vaccination on their blog. Those who chose not to post anti-vaccine content did so for fear of alienating followers or having their platform be the site of combative discourse among readers. When researching their social media posts, the influencers did not trust mainstream sources of health information and relied on alternative sources and search engines.Implications: This exploratory study interviewed influential mothers who have the ability to spread anti-vaccine messages on social media. While most do not contribute to the anti-vaccine sentiment, understanding the motivation and practices of those that do assists the public health community in better understanding the online vaccination communication environment, leading to more effective messages to counterbalance anti-vaccine content on social media.  相似文献   
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