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61.
62.
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment. Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study.  相似文献   
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This essay examines the role that entomological workers played in U.S. public health efforts during the construction of the Panama Canal (1904-1914). Entomological workers were critical to mosquito control efforts aimed at the reduction of tropical fevers such as malaria. But in the process of studying vector mosquitoes, they discovered that many of the conditions that produced mosquitoes were not intrinsic to tropical nature per se but resulted from the human-caused environmental disturbances that accompanied canal building. This realization did not mesh well with an American ideology of tropical triumphalism premised on the notion that the Americans had conquered unalloyed tropical nature in Panama. The result, however, was not a coherent counternarrative but a set of intra-administrative tensions over what controlling nature meant in Panama. Ultimately, entomological workers were loyal not just to the U.S. imperial mission in Panama but also to a modernist culture of science and to the workings of mosquito ecology as they understood them.  相似文献   
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Treatment practices for childhood posttraumatic stress disorder   总被引:4,自引:0,他引:4  
OBJECTIVE: This study surveyed practices in treating childhood PTSD among child psychiatrists and non-M.D. therapists with self-identified interest in treating traumatized children. METHOD: An anonymous survey was mailed to 207 child psychiatrists ("medical") and 460 nonphysician ("non-medical") therapists inquiring about current interventions used to treat children with PTSD. RESULTS: Two hundred and forty-seven responses were received: of 77 medical and 82 nonmedical respondents who currently treat children with PTSD, a wide variety of modalities are used. Most preferred modalities among medical responders were pharmacotherapy, psychodynamic, and cognitive-behavioral therapy. Most preferred modalities among nonmedical respondents were cognitive-behavioral, family, and nondirective play therapy. Ninety-five percent of medical respondents used pharmacotherapy for this disorder; most preferred medications to treat childhood PTSD were selective serotonin reuptake inhibitors and alpha-adrenergic agonists. Several significant differences between medical and nonmedical practices were identified. CONCLUSIONS: There is little clinical consensus regarding the effectiveness of the many modalities used to treat traumatized children who have PTSD symptoms; empirical research is particularly needed to evaluate the efficacy of pharmacotherapy and EMDR.  相似文献   
66.
The present research examined the role of maladaptive self-regulatory beliefs as vulnerability factors for academic and emotional difficulties during the transition to middle school. A short-term longitudinal design was employed to follow two groups of early adolescents: 187 adolescents who experienced a school transition between the fifth and sixth grades, and 142 adolescents who did not experience a school transition between the fifth and sixth grades. Adolescents completed measures of perceptions of academic control and importance of academic success, experience of chronic academic strain, daily school hassles, and depressive symptoms. Teachers reported on students' academic engagement, including levels of helpless behavior, effort, and academic performance. Consistent with the proposed model of self-regulation, maladaptive self-regulatory beliefs (i.e., decreased perceptions of academic control and importance) predicted individual differences in perceived school-related stress and depressive symptoms over the course of the middle school transition, but were not associated with academic and emotional difficulties in adolescents who remained in a stable school environment. Moreover, a self-regulatory sequence was identified proceeding from maladaptive self-regulatory beliefs, to academic disengagement, to enhanced perceptions of school-related stress, to depressive symptoms. This study bridges prior theory and research concerning the psychological impact of normative developmental transitions, the developmental context of depression, and the associations among self-regulatory beliefs, achievement-related behavior, and emotional experience.  相似文献   
67.
OBJECTIVE: This study explores Korean immigrant mothers' attitudes toward child physical abuse based on an ecological perspective. METHOD: One hundred and forty-four Korean immigrant mothers who came to the US after age 16 and have at least one child under 18 years old participated in this study. Data were collected using instruments translated in Korean that measure mothers' attitudes toward child physical abuse in four areas: degree of agreement with physical abuse, conflict tactics, belief in the use of physical punishment, and perceptions regarding physical abuse. RESULTS: This study found that the following variables affect Korean immigrant mothers' attitudes toward child physical abuse at ecological levels of the environment: amount of time spent with children, experience of corporal punishment as a child, children's gender and age, family acculturation conflicts, mothers' age, and length of time in US at the micro level; involvement in their children's school and involvement in social organizations at the meso level; level of education and reported stress of immigrant life at the exo level; value of children in Korean culture, familiarity with Child Protective Services (CPS), perceived discrimination, and value of corporal punishment at the macro level. CONCLUSIONS: This study suggests the importance of cultural sensitivity in social work practice when working with Korean immigrants. It also implies that intervention and prevention efforts of child abuse should be targeted at more than one level of the environment.  相似文献   
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Teachers often comment that using manipulatives to teach mathematics is ‘fun!’ Embedded in the word ‘fun’ are important notions about how and why teachers use manipulatives in the teaching of mathematics. Over the course of one academic year, this study examined 10 middle grades teachers’ uses of manipulatives for teaching mathematics using interviews and observations to explore how and why the teachers used the manipulatives as they did. An examination of the participants’ statements and behaviors indicated that using manipulatives was little more than a diversion in classrooms where teachers were not able to represent mathematics concepts themselves. The teachers communicated that the manipulatives were fun, but not necessary, for teaching and learning mathematics. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
70.
Research in Higher Education - This study examines how collegiate climates and practices can promote innovation capacities among an international longitudinal sample of undergraduate women. Using a...  相似文献   
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