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排序方式: 共有676条查询结果,搜索用时 15 毫秒
1.
Leonard A. Jason PhD Steven B. Pokorny PhD Monica Adams MPH Annie Topliff MA Courtney Harris BA Yvonne Hunt PhD 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》2009,18(5):367-374
This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use. 相似文献
2.
Does Additional Doxorubicin Chemotherapy Improve Outcome in Patients with Hepatocellular Carcinoma Treated by Liver Transplantation? 总被引:5,自引:0,他引:5
Herwig Pokorny Michael Gnant Susanne Rasoul-Rockenschaub Bernd Gollackner Birgit Steiner Günter Steger Rudolf Steininger Ferdinand Mühlbacher 《American journal of transplantation》2005,5(4):788-794
The aim of this prospective randomized study was to determine whether additional doxorubicin chemotherapy improves outcome in patients with hepatocellular carcinoma (HCCA) treated by liver transplantation. Stratification parameters were tumor stage (UICC I-IVa), gender, age 50 years, α-fetoprotein 20 ng/mL, cirrhosis and HbsAg status. For pre-operative chemotherapy doxorubicin (15 mg/m2 ) was given biweekly, intra-operative chemotherapy was a single dose administered before surgical manipulation. Post-operative chemotherapy from day 10 was as given preoperatively for a total dosage of 300 mg/m2 . Outcome parameters were overall survival (OS) and disease-free survival. Of the 75 consecutive patients who received liver transplantation for treatment of HCCA, 62 patients were enrolled. Thirty-four patients were randomized in the chemotherapy group; 28 patients were in the control group and transplanted only. OS rates at 5 years were 38% in the chemotherapy group and 40% in the control group, disease-free survival rates at 5 years 43% and 53%, respectively. Tumor stage and vascular invasion were identified as independent risk factors for recurrence of disease. Doxorubicin chemotherapy did not improve organ survival and disease-free survival in patients undergoing liver transplantation for HCCA. 相似文献
3.
Because of improvements in supportive care, many infants now survive massive intestinal loss and have short bowel syndrome. Unfortunately, some survivors are left with an insufficient amount of intestine and cannot be weaned from total parenteral nutrition. An isoperistaltic intestinal lengthening procedure was used to treat surgically two such infants with 25 centimeters of remaining small intestine and absent ileocecal valves. This surgical technique longitudinally divides the short, dilated small intestine into two smaller, parallel lumens that are anastomosed end to end. This procedure preserves all mucosa, prolongs transit time by doubling intestinal length and corrects the ineffective peristalsis by tapering the dilated intestine. The lengthening technique can be performed because of the anatomic division of the intestinal vasculature within two leaves of the mesentery. Longitudinal division between the two leaves maintains vasculature to each side of the intestine. The isoperistaltic intestinal lengthening procedure, as it was successfully applied to two infants, is described in detail. 相似文献
4.
Stereoscopic depth perception is possible when the short wave sensitive (SWS or "Blue") cones are isolated using a yellow adapting field. We have measured the maximum disparity that can be fused (the diplopia threshold) as a function of the separation between pairs of dots or lines. Under all conditions, these diplopia thresholds are the same for the isolated SWS cones as for the entire visual system. In addition, SWS diplopia thresholds vary as a linear function of dot or line separation, so that they exhibit disparity scaling. Further experiments show that disparity scaling is dependent upon the presence of low spatial frequencies in the stimulus and not upon the retinal eccentricity of stimulation. These data indicate that the SWS cones provide information to the disparity processing system through more than one low spatial frequency channel but not through high frequency ones. 相似文献
5.
Z Frühbauer J Pokorny D Zítová J Sykora M Zást?ra 《Ceskoslovenská epidemiologie, mikrobiologie, imunologie》1990,39(6):327-334
Between reactions assessing one class of immunoglobulins and reactions detecting all serum immunoglobulins comprehensively such as CFT, there is, as might be expected, a very poor quantitative correlation and thus in individual sera the result of one reaction cannot be reliably added to the result of another (CFT:ELISA/IgG). Even the correlation between reactions focused on the same Ig class (ELISA/IgG: IFT/IgG) is no better. Among reactions assessing specific IgM we consider ELISA/IgM better than IFT/IgM because there is not the risk of false negativity caused by concurrence of IgG. A combination of ELISA/IgG and ELISA/IgM gives good results as a statistical group: the distribution of results revealed agglomerations of sera corresponding to the assumed age of the infection derived from the generally accepted pattern of antibody formation. The applicability of the combination of these two reactions alone for evaluation of individual sera is a promising procedure but awaits further confirmation. Long-term investigations revealed within two years after infection a marked decline of CFT antibodies in the majority of cases but it was not sufficiently clear in ELISA/IgG. Despite the technical advantages of ELISA reactions, elimination af the CFT reaction is not foreseen in the near future. As the minimal combination of methods which provides adequate information we may consider at the present time CFT for assessment of total antibodies and ELISA/IgM for more marked differentiation of the acute stage. Evaluation of the lowest CFR titres considered hitherto as "practically negative" must be obviously revised in subjects with immunosuppression and organ donors for transplantation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Paul E. Baer Lisa Berg Garmezy Robert J. McLaughlin Alex D. Pokorny Mark J. Wernick 《Journal of behavioral medicine》1987,10(5):449-466
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence. 相似文献
7.
Leonard A. Jason Steven B. Pokorny Mazna Patka Monica Adams Taylor Morello 《Journal of community psychology》2007,35(8):967-979
Two primary outlets for community psychology research, the American Journal of Community Psychology and the Journal of Community Psychology, were assessed to rank institutions based on publication frequency and scientific influence of publications over a 32‐year period. Three specific periods were assessed (1973–1983, 1984–1994, 1995–2004). Findings indicate that there were a large group of institutions that published articles during these periods. Those academic institutions that had the most published articles as well as the largest influence, based on citations by other authors, were identified. Using archival data from the community psychology literature represents one approach for identifying those settings that made substantial contributions to the development and growth of the field. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 967–979, 2007. 相似文献
8.
Andrew A. Fulvini Akaash Tuteja Jianhua Le Barbara A. Pokorny Jeanmarie Silverman Doris Bucher 《Vaccine》2021,39(3):545-553
The only effective measure to decrease morbidity and mortality caused by the influenza virus in the human population is worldwide vaccination. Vaccination produces neutralizing antibodies that target the HA1 subunit of the HA (hemagglutinin) protein and are strain specific. The effectiveness of new influenza vaccines are linked to two factors, the correct prediction of the circulating strains in the population in a particular season and the concentration of the HA1 protein in the vaccine formulation. With the advent of the licensing of quadrivalent vaccines, pharmaceutical manufacturers are under considerable pressure due to time constraints and dedicated resources to deliver 194–198 million doses (2020–2021 U.S. market) of vaccine. Considering the valuable resources needed to produce the influenza vaccine in a timely manner, the efficient quantitation of the HA1 protein (the main component in the influenza vaccine) is required. Currently the only method approved by regulatory agencies for quantitation of the HA antigen in vaccines is the single radial immunodiffusion assay (SRID), an antibody dependent assay that is not time efficient. Time efficient methods that are antibody independent e.g. reverse phase-high performance liquid chromatography (RP-HPLC) or size exclusion-HPLC (SE-HPLC) are available. An improved method implementing reverse phase-ultra performance liquid chromatography (RP-UPLC) has been developed to quantitate the HA1 protein antigen present in the high yield reassortant vaccine seed viruses from influenza A H1N1 and H3N2 subtypes harvested from inoculated embryonated chicken eggs. This method differentiates between high yield and lower yielding reassortants in order to select the best vaccine candidate seed virus with the highest growth ‘in ovo’. This direct capability to monitor the HA1 concentration of potential reassortant seed viruses and to choose the best yielding HA influenza reassortant when faced with multiple viral seed candidates provides a major advantage on the industrial scale to the influenza vaccine process. 相似文献
9.
Albani C Villmann T Villmann B Körner A Geyer M Pokorny D Blaser G Kächele H 《Psychotherapie, Psychosomatik, medizinische Psychologie》1999,49(11):408-421
The CCRT-method developed by Lester Luborsky is the most widespread and best established method to assess relationship structures in the field of psychodynamic psychotherapy research. Although its categorical structures are criticised in many different ways there have not been any attempts to modify them. This article points out the inconsistency of the current categorical system and demonstrates first approaches to alternative solutions. For this purpose genetic algorithms are used. Their application in psychotherapy research is demonstrated here for the first time. 相似文献
10.
Pokorny LJ 《Journal of mental health administration》1991,18(2):80-87
A summary measure of clients' level of functioning could assist mental health agencies to better document and evaluate their services. Currently, numerous state mental health authorities collect a level of functioning measure within a management information system on virtually all clients served with state resources. The uses of these data include describing the clientele, defining a priority population for services, preparing performance indicators and measuring contract obligations. However, clearer delineation of the construct of functioning, further exploration of the psychometric properties of the instruments and stricter procedures to ensure the accuracy of data would result in data that are more useful for both management and research. 相似文献