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11.
J D Myers 《Clinical chemistry》1986,32(9):1714-1718
In this preliminary study concerning the applicability of expert computer systems, such as INTERNIST-I, to providing advice to clinical pathologists regarding patients' diagnoses and the pertinence of performing further laboratory tests, 32 complex cases, drawn from Case Records of the Massachusetts General Hospital, were analyzed diagnostically by computer, on the basis of clinical laboratory data only. Half (16 cases) were diagnosed correctly, but in 15 of the rest no diagnostic conclusion could be reached. However, no diagnostic errors were made. The study provides preliminary evidence that expert computer systems can be useful to clinical pathologists and clinical internists in guiding the laboratory workup of patients toward correct diagnosis.  相似文献   
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The involvement of children in research studies is historically fraught with difficulties. Experiments on children without their consent or knowledge have been carried out in the past and thus the need for stringent ethical control is undoubtedly necessary. However this paper argues that the need to protect children from unethical research has somehow become entwined in the web of secrecy that surrounds the very nature of child abuse. In the name of 'protection' are children in danger of not having their voice heard?

In the foreword to 'Listening to Children' (Alderson, 1995) Roger Singleton writes, 'much research is carried out on and about children, but seldom with children. Children themselves are often strangely silent'. This paper draws on recent literature on the institutional abuse of young people in residential care and the lack of voice that those abused in residential care have traditionally had, suggesting that their silence is not 'strange' but perhaps contrived.

This paper does not repeat the work of Alderson (1995) and make suggestions as to how research with children may best be carried out, but seeks to address the issues in relation to research with children who are in institutions.  相似文献   
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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   
15.
A model for training the trainers of child care providers that employs Vygotsky's framework of the Zone of Proximal Development is described. This efficient training mechanism proposes mentoring relationships as a means to meet the developmental needs of experienced child care professionals and improve the quality of existing child care programs.The authors would like to thank Dr. Bille Thomas and the satellite resource center directors and staff members for their work on the project.  相似文献   
16.
In the presence of fixed basal levels of insulin, the route of intravenous glucose delivery (protal vs. peripheral) determines whether net hepatic glucose uptake (NHGU) occurs. Our aims were to determine if the route of intravenous glucose delivery also plays a role in regulating NHGU in the presence of hyperinsulinemia and to determine if length of fast (18 vs. 36 h) influences regulation of NHGU. Five conscious dogs fasted 18 h were given somatostatin and replacement insulin (245 +/- 34 microU.kg-1.min-1) and glucagon (0.65 ng.kg-1.min-1) infusions intraportally. After a 40-min control period, the insulin infusion rate was increased fourfold, and glucose was infused for 3 h. Glucose was given either through a peripheral vein or the portal vein for 90 min to double the glucose load reaching the liver. The order of infusions was randomized. NHGU was measured with the arterial - venous difference technique. Insulin and glucagon levels were 12 +/- 2, 35 +/- 6, and 36 +/- 5 microU/ml and 55 +/- 12, 61 +/- 13, and 59 +/- 7 pg/ml during the control, peripheral, and portal infusions, respectively. The glucose infusion rate, the load of glucose reaching the liver, and the arterial-portal plasma glucose gradient were 0, 9.58 +/- 2.28, and 10.44 +/- 2.94 mg.kg-1.min-1; 29.4 +/- 3.6, 56.8 +/- 3.4, and 56.8 +/- 2.8 mg.kg-1.min-1; and 2 +/- 1, 5 +/- 1, and -51 +/- 15 mg/dl during the same periods.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Using the concepts of stigma, NIMBY and place, this paper examines the difficulties of finding a place for needle exchange programs (NEPs). Data were drawn from semi-structured interviews with NEP staff (Ontario, Canada) that focused on operational policies and routines. An iterative, inductive analytic process was used. NEPs, their staff and clients are not always welcome additions to organizations or communities because of concerns about the ‘dangerousness’ of clients and the potential contamination of communities and workplaces by stigmatized individuals and their artefacts (e.g. contaminated injection equipment). Public parks where a lot of drug ‘action’ takes place are good destinations for outreach workers but these places are contentious sites for NEP activities, particularly when residents do not perceive a need for the program and/or want to redefine their neighbourhoods. Issues of ‘place’ are further complicated when service delivery is mobile. Finding a place within organizations is difficult for NEPs because of concerns about the diversion of limited financial and spatial resources to ‘non-core’ activities and ‘undesirable’ clients. Workers respond to these challenges by contesting the social and spatial boundaries of who is an acceptable client or neighbour and refuting the perceived ‘differentness’ of injection drug users. Implementation of an unpopular service involves a delicate balancing act of interests, understanding of the dynamics of particular communities and a willingness to reinvent and redefine programs. The sociospatial stigmatization of injection drug use has had a negative impact on NEPs, and perhaps limits HIV prevention efforts.  相似文献   
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The radiographic findings in 24 cases of bronchiolitis obliterans with organizing pneumonia and 16 cases of usual interstitial pneumonia were reviewed and compared. Some cases of bronchiolitis obliterans with organizing pneumonia have been mistaken for usual interstitial pneumonia, although the two diseases have distinct pathologic findings. Clinically, the diseases often have different manifestations. Bronchiolitis obliterans with organizing pneumonia has a better prognosis and often responds well to steroids. This study shows that the radiologic findings of bronchiolitis obliterans include alveolar opacities without lung-volume loss. Patients with usual interstitial pneumonia, however, have bilateral diffuse interstitial opacities with occasional honeycomb changes, and there is loss of lung volume in most patients. These findings suggest that the chest radiograph can aid in distinguishing the two diseases.  相似文献   
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