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OBJECTIVE: The National Institute of Mental Health developed the Depression Awareness, Recognition, and Treatment Program to provide up-to-date information and training to health, mental health, and social service professionals regarding the identification and treatment of depression. This study was undertaken to evaluate a series of these programs for professionals who provide services to rural residents in the Midwest. METHOD: The 18 2-day training programs were attended by a total of 1,221 participants, physicians, psychologists, social workers, and nurses. Participants' knowledge regarding depression was assessed both before and after each program. Practice characteristics and perceived ability to assess and treat depression were assessed. Finally, 6-month follow-up evaluations of the usefulness of the training to the participants were undertaken. RESULTS: Following the programs, participants evidenced significant increases in levels of knowledge of depression and a high degree of satisfaction with most elements of the program. Six-month follow-up evaluations indicated a continued positive evaluation of the program. CONCLUSIONS: These outcomes suggest that the goals of the Depression Awareness, Recognition, and Treatment Program were met and provide support for the wider dissemination of these training programs.  相似文献   
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DNA encoding a single unit of the DvA-1 polyprotein of the parasitic nematode Dictyocaulus viviparus was isolated and the polypeptide ("rDvA-1L") expressed in Escherichia coli, to give a protein showing high binding affinity for fatty acids and retinoids. Fluorescent fatty acid probes show substantial changes in emission spectrum in the presence of rDvA-1L, which can be reversed by fatty acids (oleic, palmitic, stearic, arachidonic) and retinoids, but not by tryptophan, squalene, or cholesterol. Moreover, changes in intrinsic fluorescence of retinol or retinoic acid confirm a retinoid binding activity. Fluorescence titration experiments indicate stoichiometric binding to a single protein site per monomer unit with affinities (Kd) in the range 3 x 10(-8) M for 11-((5-dimethylaminonaphthalene-1-sulfonyl)amino)undecanoic acid, and by competition, 5 x 10(-8) M for oleic acid. The extreme blue shift of bound fluorescent fatty acid suggests an unusually low polarity for the protein binding site. The emission spectrum of the single tryptophan of rDvA-1L indicates that it is deeply buried in a nonpolar environment, and its spectrum is unaffected by ligand binding. Far UV circular dichroism of rDvA-1L reveals a high alpha-helix content (53%). Differential scanning calorimetry studies indicate that rDvA-1L is highly stable (T(m) approximately 98 degrees C), refolding efficiently following thermal denaturation. DvA-1 therefore represents an example of a new class of lipid binding protein, and is the first product of a polyprotein with this activity to be described.  相似文献   
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Since its discovery 10 years ago PCR has been introduced for a variety of practical applications. PCR has opened new dimensions particularly in laboratory diagnostics because of its sensitivity, accuracy and speed. In spite of the availability of user friendly kits, basic knowledge is of great importance for the user especially if PCR has to be optimized for special needs or when specific problems arise. The general mechanism of the reaction and the significance of the reaction components and the PCR conditions are discussed initially. Several recent developments in PCR (new enzymes, RNA-PCR, improvements of the specificity, prevention of contamination and development of new equipment) that are critical for the user are shortly introduced. Finally, "long PCR" is discussed in order to demonstrate that even 10 years after the invention of PCR significant new breakthroughs in the PCR technology are still possible.  相似文献   
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BACKGROUND: The purpose of this study was to determine whether imbrication of native fascia versus excision and closure of new raw fascia forms a stronger union. METHODS: We utilized the anterior rectus sheath fascia of Sprague-Dawley rats as the model. Sixty rats underwent fascial tightening procedures. Each rat had the anterior rectus sheath shortened by 1 cm, 30 by imbrication and 30 by excision and closure. Ten of each group were harvested at 7 days' healing, 10 at 14 days, and 10 of each group at 28 days' healing. The anterior rectus sheath was removed, a "dumbbell" shape constructed, and the cross sectional area at the point of interest determined. The fascia was placed on an Instron tensiometer to determine the breaking strength. Tensile strength was calculated and the data analyzed by ANOVA and the Kruskall-Wallis test. Tissue samples of the closures were histologically analyzed for fibroblast counts, degree of inflammation, and presence of dense fibrous connective tissue. Tissue samples were also analyzed for enzymatic collagen crosslinking. RESULTS: There was a statistically significant difference in tensile strength between the two groups at 7, 14, and 28 days. Results show that at 7 days the mean tensile strength of excision was 0.133 kg/mm2 +/- 0.056 and the mean tensile strength of imbrication was 0.083 kg/mm2 +/- .048 (P < 0.05); at 14 days the mean tensile strength of excision was 0.105 kg/mm2 +/- 0.033 and the mean tensile strength of imbrication was 0.057 kg/mm2 +/- 0.014 (P < 0.002), and at 28 days the mean tensile strength of excision was 0.279 kg/mm2 +/- 0.143 and the mean tensile strength of imbrication was 0.145 kg/mm2 +/- 0.061 (P < 0.03). Histologic findings showed no statistical significance between the two closure methods when comparing degree of inflammation or the number of fibroblasts present. However, at 7 and 14 days there is a significantly greater presence of dense fibrous connective tissue in the excision group (P < 0.03 at 7 days and P < 0.044 at 14 days by ANOVA). Collagen crosslink analysis showed that by day 28 there is a significantly greater amount (P < 0.05 by ANOVA) of the difunctional crosslink dihydroxylysinonorleucine (DHLNL) and a greater ratio between DHLNL and the difunctional crosslink hydroxylysinonorleucine (HLNL) in the excision and closure group. CONCLUSION: We conclude that at 7, 14, and 28 days healing, excision provides a significantly stronger closure than imbrication. According to the crosslinking analysis, it is likely that this strength advantage may continue to increase over time. These findings suggest that excision and closure may be the preferred method for fascial tightening procedures.  相似文献   
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Diminution of apparent ultrasonic cell lysis in vitro with increasing cell concentration/volume fraction has often been observed. A substantial fraction of the cells may be lysed by ultrasound at low cell concentrations, but only a few percent are lysed when the concentration is a fraction of that of whole blood. This suggests that sonolysis of cells in vitro is suppressed by high cell concentrations, and, therefore, that sonolysis of cells in vivo is unlikely. We present the results of a retrospective analysis of experimental data and a theoretical analysis; these indicate that while relative sonolytic yield declines with increasing cell concentration, the "absolute" extent of ultrasound-induced lysis remains large. We find evidence that in vitro sonolysis of cells is limited at high cell densities by the number of available microbubbles and/or the number of cells each bubble may encounter and lyse prior to bubble "inactivation." Theory indicates the latter arises in consequence to the cell concentration-dependent formation of cell aggregates around pulsating bubbles.  相似文献   
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