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111.
OBJECTIVES: To determine the incidence of and risk factors associated with infant (< 1 year of age) physical abuse in Alaska. METHODS: A population-based retrospective cohort study for the 1994-2000 resident birth cohort was conducted by linking data from birth certificates, Child Protective Services, a statewide hospital-based trauma registry, hospital discharge data, and the Alaska Infant Mortality Review (including death certificates). The main outcome measures were the incidences of overall physical abuse and abuse resulting in hospitalization or death. A case of child abuse was defined as an instance of substantiated physical abuse to an infant identified in the Child Protective Services database or an infant death with homicide identified on the death certificate as the manner of death. RESULTS: During the 7-year study period, there were 70,842 births and 325 cases of physical abuse including 72 that led to hospitalization (n = 58), death (n = 4), or both (n = 10); respective incidences for all abuse and abuse leading to hospitalization or death were 4.6 and 1.0 per 1000 live births. Following multivariate analyses, the risk factors with the highest population attributable risks were maternal or paternal education < or = 12 years, unmarried mother, and maternal prenatal substance use. To determine if the study methodology was likely to have missed cases of severe abuse, we examined information for all 216 infants hospitalized for trauma during the study period who did not have identification of abuse in one of the study databases; of these, at least 39 had injuries inconsistent with the reported mechanism (a long bone or skull fracture that reportedly resulted from a fall of less than 3 feet or from a caretaker's arms or for which the caretaker denied a history of trauma). Conclusions: Alaska has one of the highest documented infant physical abuse incidences reported in the literature and abuse is associated with potentially modifiable-primarily social-risk factors. Despite this high incidence, substantial under-reporting of hospitalized cases likely occurs.  相似文献   
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113.
Tseng V 《Child development》2006,77(5):1434-1445
This study sought to unpack how immigration is associated with youths' educational choices during the transition to college and adulthood. Surveys and school records were collected on 789 youth (ages 18-25) with Asian Pacific, Latino, African/Afro-Caribbean, and European backgrounds. The results indicated generational differences in educational choices, such that children of immigrants chose courses of study with higher math and science content than that of their peers with U.S.-born parents. Mediation analyses indicated that children of immigrants reported higher social and economic aspirations than did their peers, and their economic aspirations accounted for part of the generational difference in educational choices. Generational differences in educational choices were also mediated by verbal achievement test scores and perceived English skills.  相似文献   
114.
Rats will approach and contact a lever whose insertion into the chamber signals response-independent food delivery. This “autoshaping” or “sign-tracking” phenomenon has recently attracted considerable attention as a platform for studying individual differences in impulsivity, drug sensitization, and other traits associated with vulnerability to drug addiction. Here, we examined two basic stimulus selection phenomena—blocking and overshadowing—in the autoshaped lever pressing of rats. Blocking and overshadowing were decidedly asymmetrical. Previously reinforced lever-extension conditioned stimuli (CSs) completely blocked conditioning to auditory cues (Exps. 1 and 2), and previously nonreinforced lever-extension CSs overshadowed conditioning to auditory cues. By contrast, conditioning to lever-extension CSs was not blocked by either auditory (Exp. 3) or lever-insertion (Exp. 4) cues, and was not overshadowed by auditory cues. Conditioning to a lever-insertion cue was somewhat overshadowed by the presence of another lever, especially in terms of food cup behavior displayed after lever withdrawal. We discuss several frameworks in which the apparent immunity of autoshaped lever pressing to blocking might be understood. Given evidence that different brain systems are engaged when different kinds of cues are paired with food delivery, it is worth considering the possibility that interactions among them in learning and performance may follow different rules. In particular, it is intriguing to speculate that the roles of simple cue–reinforcer contiguity, as well as of individual and aggregate reinforcer prediction errors, may differ across stimulus classes.  相似文献   
115.
Non-Hodgkin’s lymphoma constitutes a group of disorders originating from the malignant transformation of lymphocytes and involving either the lymph nodes or extranodal sites. NHL commonly presents in the sixth to seventh decade of life with a male preponderance (50–75 %). Recent studies have shown importance of serum LDH in prognosis of NHL. Authors report a case of a 63 year old male presenting with complaints of fever and backache for past 4 months. General and systemic examination revealed bilateral axillary lymphadenopathy and splenomegaly respectively. Serum LDH level was highly elevated (3441 U/l). Excisional axillary and bone marrow biopsy were done before oncology referral. Complete workup revealed diffuse Non-Hodgkin’s lymphoma with bone marrow infiltration. Patient died because of acute renal failure due to NHL and DM 2 (Type 2 diabetes mellitus).  相似文献   
116.
In order to engage their students in a core methodology of the new genomics era, an ever-increasing number of faculty at primarily undergraduate institutions are gaining access to microarray technology. Their students are conducting successful microarray experiments designed to address a variety of interesting questions. A next step in these teaching and research laboratory projects is often validation of the microarray data for individual selected genes. In the research community, this usually involves the use of real-time polymerase chain reaction (PCR), a technology that requires instrumentation and reagents that are prohibitively expensive for most undergraduate institutions. The results of a survey of faculty teaching undergraduates in classroom and research settings indicate a clear need for an alternative approach. We sought to develop an inexpensive and student-friendly gel electrophoresis-based PCR method for quantifying messenger RNA (mRNA) levels using undergraduate researchers as models for students in teaching and research laboratories. We compared the results for three selected genes measured by microarray analysis, real-time PCR, and the gel electrophoresis-based method. The data support the use of the gel electrophoresis-based method as an inexpensive, convenient, yet reliable alternative for quantifying mRNA levels in undergraduate laboratories.  相似文献   
117.
Our Introduction to Biology course (BIOL 1010) changed in 2004 from a standard instructor-centered, lecture-homework-exam format to a student-centered format that used Web-enhanced, interactive pedagogy. To measure and compare conceptual learning gains in the traditional course in fall 2003 with a section of the interactive course in fall 2004, we created concept inventories for both evolution and ecology. Both classes were taught by the same instructor who had taught BIOL 1010 since 1976, and each had a similar student composition with comparable biological knowledge. A significant increase in learning gain was observed with the Web-enhanced, interactive pedagogy in evolution (traditional, 0.10; interactive, 0.19; p = 0.024) and ecology (traditional, -0.05; interactive, 0.14; p = 0.000009) when assessment was made unannounced and for no credit in the last week of classes. These results strengthen the case for augmenting or replacing instructor-centered teaching with Web-enhanced, interactive, student-centered teaching. When assessment was made using the final exam in the interactive course, for credit and after studying, significantly greater learning gains were made in evolution (95%, 0.37, p = 0.0001) and ecology (143%, 0.34, p = 0.000003) when compared with learning gains measured without credit or study in the last week of classes.  相似文献   
118.
Fatty acids and derivatives (FADs) are resources for natural antimicrobials. In order to screen for additional potent antimicrobial agents, the antimicrobial activities of FADs against Staphylococcus aureus were examined using a microplate assay. Monoglycerides of fatty acids were the most potent class of fatty acids, among which monotridecanoin possessed the most potent antimicrobial activity. The conventional quantitative structure-activity relationship (QSAR) and comparative molecular field analysis (CoMFA) were performed to establish two statistically reliable models (conventional QSAR: R 2=0.942, Q 2 LOO=0.910; CoMFA: R 2=0.979, Q 2=0.588, respectively). Improved forecasting can be achieved by the combination of these two models that provide a good insight into the structure-activity relationships of the FADs and that may be useful to design new FADs as antimicrobial agents.  相似文献   
119.
The purpose of this study was to examine gender differences in upper and lower body strength as a function of lean body weight and the distribution of muscle and subcutaneous fat in the upper and lower limbs. The subjects were 103 physically active men (n = 48) and women (n = 55). The peak torques produced during shoulder flexion (SF) and knee extension (KE) were used as measures of upper body and lower body strength, respectively. Flexed arm girth, thigh girth, triceps skinfold, and thigh skinfold were used to estimate the distribution of muscle and subcutaneous fat in the limbs. Results of the MANOVA revealed that the overall strength of men was significantly greater than that of women. Results of MANCOVA indicated that the SF and KE strength of women and men did not differ significantly when differences in lean body weight, arm girth, thigh girth, triceps skinfold and thigh skinfold were statistically controlled. High levels of SF and KE strength were associated with a high lean body weight and a large arm girth. Results of the multiple regression analysis indicated that for men a substantial portion of the variance in both SF and KE strength was explained by lean body weight alone; whereas strength variations in women were explained more adequately by including limb variables along with lean body weight. Within the limitations of this study, it was concluded that gender differences in upper and lower body strength are a function of differences in lean body weight and the distribution of muscle and subcutaneous fat in the body segments. Upper body strength is relatively more important than lower body strength in characterizing the gender difference in strength.  相似文献   
120.
This article highlights the extent to which international law has changed rapidly in recent years in relation to the rights of Indigenous peoples generally and in particular how this impacts upon the legal status of traditional knowledge and culture. It reviews the recognition of the unique legal status of Māori in Aotearoa and Aboriginal peoples in Canada in relation to self-determination and how their changing place within these nations are affecting the operations of museums, libraries, and archives as case studies, illustrating some of the key legal and practical challenges that now impinge upon the work of archivists and related professionals in many countries.  相似文献   
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