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71.
72.
OBJECTIVE: Our purpose is to present findings regarding student attitudes towards a virtual PBL program used to standardize their pediatric clinical experience. DESCRIPTION: With funding provided by the Fund for the Improvement of Post-Secondary Education, we developed Project LIVE (Learning through Interactive Video Education), a CD-ROM/Web hybrid program that uses digital video cases to conduct "virtual" problem-based learning groups with students doing a clinical rotation in a remote setting. Cases were progressively disclosed by videos of patient/physician encounters on a CD-ROM. Groups of five students and a faculty facilitator collaborated, teaching each other within the discussion section of the program. We conducted a multifaceted evaluation of Project LIVE to study the impact of case modality or distance on student learning and attitudes. We placed students in one of three groups (1) a face-to-face group with a paper case (FFT), (2) a face-to-face group with a video case (FFV), and (3) a virtual group (VG) with the digital video case. We then studied student attitudes about the three teaching formats. Over a six-month period three education specialists, who were not a part of the development team, conducted eight focus groups lasting one hour to assess student attitudes about Project LIVE. No one from the project team was present during these groups, and an independent evaluator analyzed the notes taken by each focus group leader. DISCUSSION: Trends across the groups included the following: (1) Authenticity (video)-Students reported that the authenticity of the case was a critical feature and that, "seeing (videos) made learning more memorable." Virtual and FFV groups reported more confidence in their ability to recognize abnormal findings in their patients. "You can't expect to teach clinical exam skills with a piece of paper." (2) Use of time-Students from all groups believed the cases were a good use of their time and improved their ability to solve clinical problems. They said it gave them an opportunity to "get away from just doing and focus on learning." However, the virtual groups complained of the lack of "a barometer for how much is too much" time. Some students reported spending an average of eight to ten hours per case over the period of a week. (In contrast, face-to-face groups met for three hours.) (3) Modeling clinical reasoning-Students believed the cases were valuable in structuring their knowledge, conceptualizing how to handle difficult situations, distinguishing abnormal from normal physical examination findings, and collaborating with their peers and their mentor to develop critical thinking. "It forced us to be logical" and ". how to think through the process-it mimics the real setting." (4) Technical support-The responsiveness of the Project LIVE staff was essential in assisting students in troubleshooting problems. (5) Distance component-Students preferred to work through the cases in face-to-face groups but agreed that the virtual experience is "good if you are in the middle of nowhere." This program was enjoyed by students and gave us an approach to standardizing experiences across multiple clinical sites.  相似文献   
73.
Immunological activity to various antigens, including brain components, measles and other viruses, has been associated with IgG in multiple sclerosis (MS). One possible explanation for the presence of anti-viral antibodies and antibody to myelin basic protein (MBP) in MS patients is that there are antigenic determinants common to certain viruses and MBP. To assess this possibility, IgG from individual brains and sera from patients with MS, subacute sclerosing panencephalitis (SSPE) and controls was isolated by protein A and MBP-Sepharose affinity chromatography. Antibody to MBP was measured with a solid phase radioimmunoassay and antibody to measles and other viruses by immunofluorescence and/or complement fixation. Anti-MBP activity was detected in brain extracts and sera of all MS patients tested. In contrast to the low levels of antibody to MBP in control brains, high levels of anti-MBP antibodies were found in most of the normal sera. There was no correlation between the presence and levels of serum anti-measles antibodies and the anti-MBP activity. None of the anti-MBP antibodies affinity purified from brain and serum of MS patients reacted with any of the viruses tested, including measles. IgG purified from SSPE patients or from a rabbit hyperimmunized with measles antigen had no reactivity to MBP, despite high levels of anti-measles antibody. It is concluded that there is not direct link between the presence of antibody to MBP and antibody to measles and other viruses in MS patients.  相似文献   
74.
75.
Telechelic aromatic diamines ( 11 ) containing an oligo- or polysiloxane chain were prepared in a 4-step synthesis. In the first step 1-allyloxy-4-nitrobenzene ( 6 ) was synthesized and subsequently hydrosilylated with chlorodimethylsilane. In the third step the product ( 7 ) was hydrolyzed or condensed with α-hydro-β-hydroxyoligo- or polydimethylsiloxane ( 9a or 9b ). In the last step the nitro groups were reduced into amino groups. The steps were controlled by means of 1H and 29Si NMR spectroscopy.  相似文献   
76.
Grant  D.  Long  W. F.  Mackintosh  G.  Williamson  F. B. 《Inflammation research》1994,41(2):C214-C215

Chronically inflamed tissues contain significant concentrations of oxygen radicals, possibly generated by transition metal species such as Fe(II) and Cu(I). In addition, the pH of such tissues may well be lower than that of normal counterpart tissues. In this communication, the effect of variation of pH on the antioxidant activity of caeruloplasmin (a copper-containing acute-phase protein possessing important ferroxidase and other antioxidant activities) and of heparin are reported. Heparin, unlike caeruloplasmin, retains antioxidant activity at low pH. Heparins possess a variety of metal cation-binding chemical groups allowing them to bind damaging Cu(I) and Fe(II) ions and consequently prevent their redox involvement in oxygen radical-generating Fenton reactions. In conclusion, heparins may function as endogenous antioxidants and sequestration and/or oxidation by them, of ions such as Fe(II), may contribute to their effectiveness.

  相似文献   
77.
The use of elongated prophase and prometaphase chromosome preparations has allowed detection of an insertion of a small segment of 3q into 11q in a kindred with 4 balanced carriers and 8 unbalanced offspring. Those with partial 3q deletion have a true multiple congenital anomalies/mental retardation (MCA/MR) syndrome with an appearance suggestive of the Schwartz-Jampel syndrome.  相似文献   
78.
A study of caries experience and gingivitis prevalence in 6-, 9- and 12-yr-old children attending primary schools in Brisbane was undertaken in November/December 1983. Children from high socioeconomic level (SEL) schools exhibited lower dmft and DMFT scores at all ages. At age 6 yr the proportion of children with caries-free primary dentitions was for high SEL Schools 70%, for middle SEL schools 52% and for low SEL Schools 23%. At 12 yr DMFT scores were 1.8 (high), 2.1 (middle) and 3.3 (low). Similar differences in gingivitis prevalence occurred, children from high SEL schools displaying a much lower proportion of bleeding sites than those from middle and low SEL schools. For selection of children at "high risk" to gingival disease for intensive prevention programmes, an increased emphasis on probing techniques is indicated to achieve diagnostic consistency.  相似文献   
79.
Responding to a preceding article by Michael J. Newton ("Moral dilemmas in surgical training: intent and the case for ethical ambiguity"), Downie comments on three of Newton's themes. He agrees that trainees should engage in ethical self-appraisal but cautions that introspection is inappropriate at the time of an operation. Regarding Newton's downplaying of philosophical analysis in medical ethics, Downie agrees that there are limitations to the philosophical approach but contends that it can serve a very worthwhile function in helping doctors deal with ethical uncertainties. Finally, Downie perceives ambiguities in Newton's emphasis on the central importance of "ethical intent," which rejects the idea of ethical standards while urging individuals to take "personal responsibility" for their actions.  相似文献   
80.
Alcohol consumption and many alcohol-related problems have increased in most industrialized countries in the postwar period. The main societal responses have been increases in the treatment response to alcohol problems and in public and school education efforts. In the present era of fiscal crisis, there is also a trend toward punitive controls of the individual drinker. Potential policy alternatives should be broadened to include environmental protections for and from drunkenness, and a reconsideration of alcohol control strategies. Recent studies have shown that in some circumstances such laws have strong effects.Revised from a paper presented at a Plenary Session on Alcohol and Public Policy at the 28th International Institute on the Prevention and Treatment of Alcoholism, Munich, West Germany, July 9, 1982. Preparation of this article was supported by NIAAA National Alcohol Research Center grant (AA-05595) to the Alcohol Research Group, Institute of Epidemiology and Behavioral Medicine, Medical Research Institute of San Francisco, 1816 Scenic Ave., Berkeley, CA 94709.  相似文献   
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