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81.
82.
BACKGROUND: Factors associated with Asian/Pacific-Islander adolescent adjustment is a greatly neglected research area. AIMS: The purpose of the present study was to investigate the relation between demographic, social and adjustment measures based on a large-scale investigation of Asian/Pacific-Islander youths. METHOD: A total of 2577 adolescents were surveyed across 4 public schools in Hawai'i during the 1992--1993 school year. RESULTS: Three social variables (number of relatives frequently seen, family support and friends' support) exhibited statistically significant but low correlations. Family support had the highest negative association with the four psychiatric symptoms (depression, anxiety, aggression, substance use). Friends' support was inconsistently associated with the adjustment measures, and the number of relatives frequently seen resulted in negligible effects. In contrast, demographic variables, especially ethnicity, played a much greater role in the association with the four school-related measures (grade-point average, absences, suspensions, conduct infractions). DISCUSSION: For Asian/Pacific-Islander youths, the quality of the social supports, including family relations, may be particularly important in the adolescents' adjustment. When examining school-related outcomes, demographic variables, with particular emphases on ethnicity and culture, must be considered. When developing and implementing prevention and intervention services and programs, consideration of family and ethnic-cultural influences should be taken into account, with further research needed in several related domains: other SES influences, life stressors, migration-generational effects, ethnic identity, self-concept indicators and socio-political aspects.  相似文献   
83.
Enteropathogenic Escherichia coli (EPEC) has been associated with infantile diarrhea and mortality in humans in developing countries. While diarrhea is also a major problem among primates kept in captivity, the role of E. coli is unclear. This study was designed to characterize diarrheagenic E. coli recovered from the feces of 56 New World nonhuman primates, primarily marmosets (Callithrix spp.). Seventeen of the 56 primates had signs of diarrhea and/or enteritis. E. coli recovered from feces from these animals was tested by PCR for genes encoding virulence factors of diarrheagenic E. coli and for patterns of adherence to HeLa cells. In addition, isolates were characterized by the fluorescence actin staining test and by their ability to induce attaching and effacing lesions. PCR for the eae gene was positive in 10 of the 39 (27%) apparently healthy animals and in 8 of the 17 (47%) animals with diarrhea and/or enteritis. Colonies of eae(+) E. coli were serotyped and examined by PCR for genes encoding EPEC virulence markers. The eae(+) E. coli isolates recovered from both healthy and sick nonhuman primates demonstrated virulence-associated attributes similar to those of EPEC strains implicated in human disease and are designated monkey EPEC. The results presented here indicate that EPEC may be a significant pathogen for nonhuman primates, deserving further investigation. The similarities between the affected animals investigated in this study and human EPEC infections suggest that marmosets may represent an important model for EPEC in humans.  相似文献   
84.
Seven fresh animal carcasses were monitored throughout decomposition in a mixed flatwood forest in East Baton Rouge Parish, LA from 1 April to 1 July 1999. Succession patterns of necrophilous insects were documented for the following: one Louisiana black bear (threatened species), two white-tailed deer, two alligators, and two swine as the experimental reference. Our results suggest variation in the species composition of necrophilous insects among animal carcass types. A total of 93 arthropod species, from 46 families and three classes, were manually collected from the seven carcasses. Only 19 insect species were collected on all four animal types and were represented by eight families: Coleoptera: Histeridae, Nitidulidae, Silphidae, Staphylinidae; Diptera: Calliphoridae, Muscidae, Piophilidae, Sepsidae. Eleven of the 46 families were not collected at either alligator site but were observed at bear, deer, and swine carrion: Coleoptera: Cleridae, Dermestidae, Geotrupidae, Scarabaeidae; Diptera: Micropezidae, Sarcophagidae, Syrphidae; Hymenoptera: Apidae; Lepidoptera: Nymphalidae; and Odonata: Libellulidae. Residency and succession patterns of necrophilous insects are presented for each animal type with particular emphasis on selected fly (Calliphoridae, Muscidae, Piophilidae, Stratiomyidae) and beetle species (Cleridae, Dermestidae, Histeridae, Nitidulidae, Silphidae, Staphylinidae).  相似文献   
85.
BACKGROUND: Renal transplantation is the therapy of choice for patients with end-stage renal disease (ESRD). However, African Americans' (AA) access to this modality is not commensurate with that of other races. This imbalance, coupled with AA disproportionately representing those with ESRD, has kept AA disadvantaged compared with other races, especially whites. METHODS: We reviewed published reports that examined the connection between race and the incidence of chronic renal failure, access to optimal therapy, and outcomes of renal transplantation. RESULTS: The incidence of ESRD in AA is 4 times greater than in whites, but AA remain less likely than whites to be referred for or undergo renal transplantation. Also, AA are at greater risk than whites to experience premature graft failure. CONCLUSIONS: ESRD management has improved dramatically with the advent of successful renal transplantation. However, AA remain significantly disadvantaged in both access and outcomes compared with whites. Further evaluation of underlying causes and development of specific remedies is warranted.  相似文献   
86.
87.
Prostate cancer metastasis to bone may be mediated by preferential proliferation of these cells in the bone's microenvironment. We hypothesize that this preferential proliferation is mediated by bone-associated growth factors (GFs) and cytokines. To test our hypothesis, human prostate cancer cells, derived from both soft tissue (LNCaP, DuCaP, DU145) and bone metastases (PC-3, VCaP, MDA-2a, MDA-2b), were treated with bone-associated GFs and cytokines (PDGF, IGF-1, TGF-beta, EGF, bFGF, TNF-alpha, IL-1, and IL-6) for 48 h, and their growth responses were compared. The responses of soft tissue-derived prostate cancer cell lines to bone GFs and cytokines were variable. LNCaP cell growth was stimulated by IGF-1 but was inhibited by TNF-alpha. DU145 cell growth was stimulated with EGF. Prostate cancer cell lines derived from bone metastases also responded variably to bone GFs and cytokines. IL-1 stimulated the growth of MDA-2a and 2b cell lines in a dose-dependent manner. PDGF and bFGF both demonstrated variable effects on bone-derived prostate cancer cell lines. TNF-alpha inhibited proliferation of the VCaP cells. These findings demonstrate that human prostate cancer cell lines derived from bone metastases may not respond preferentially to bone-associated GFs and cytokines.  相似文献   
88.
Ventilated sanders are commonly used during aircraft surface abrasion but there is limited data on their effectiveness in reducing worker exposures. This study compared two handheld ventilated sander brands, DCM and Dynabrade, in a laboratory glovebox. Both sanders collect particulates by drawing air through holes in the sanding pads; the dust subsequently passes into a vacuum collection system. Aluminum panels coated with aircraft epoxy primer and polyurethane paint were abraded and inhalable dust concentrations were measured inside the glovebox with IOM samplers. The results indicate that both sanders effectively control inhalable dust, with the DCM sander reducing mass concentrations by 93 percent, and the Dynabrade by 98 percent, when the ventilation system is used. The Dynabrade unit, however, was more aggressive and produced over four times as much dust per unit time as the DCM unit. In spite of this, the Dynabrade sander adequately collected this additional dust. Varying abrasive grit size did not significantly affect dust generation, although the differences between the grit sizes used (180 and 240 grit) were not great and may have influenced the results.  相似文献   
89.
Despite 10 years of intensive education and training in Australia only around 14% of hysterectomies are performed with laparoscopic assistance. In particular total laparoscopic hysterectomy (TLH) has a poor penetration rate because of perceived technical difficulties that include instrumentation, prolonged operating times and an increase in complications. We present a series of 200 consecutive cases of TLH with very good results and propose that because of the many advantages that this technique offers that it should become the standard procedure for benign uterine disease.  相似文献   
90.
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