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101.
CONTEXT: Composed of all or a portion of 13 states, Appalachia is a heterogeneous, economically disadvantaged region of the eastern United States. While mortality from cancer in Appalachia has previously been reported to be elevated, rates of cancer incidence in Appalachia remain unreported. PURPOSE: To estimate Appalachian cancer incidence by stage and site and to determine if incidence was greater than that in the United States. METHODS: Using 1994--1998 data from the central registries of Kentucky, Pennsylvania, and West Virginia, age-adjusted incidence rates were calculated for the rural and nonrural regions of Appalachia. These state rates were compared to rates from the Surveillance, Epidemiology, and End Results (SEER) program for the same years by calculating the adjusted rate ratio (RR) and a 95% confidence interval (CI). FINDINGS: Both the entire and rural Appalachian regions had an adjusted incidence rate for all cancer sites similar to the SEER rate (RR = 1.00 [95% CI, 1.00-1.01] and RR = 0.99 [95% CI, 0.99-1.00], respectively). However, incidence of cancer of the lung/ bronchus, colon, rectum, and cervix in Appalachia was significantly elevated (RR = 1.22 [95% CI, 1.20-1.23], 1.13 [95% CI, 1.11-1.14], 1.19 [95% CI, 1.16-1.22], and 1.12 [95% CI, 1.07-1.17], respectively). Incidence of cancer of the lung/bronchus and cervix in rural Appalachia was even more elevated (RR = 1.34 [95% CI, 1.31-1.36] and 1.29 [95% CI, 1.21-1.38], respectively). Incidence of unstaged disease for all cancer sites in Appalachia (RR = 1.06 [95% CI, 1.05-1.08]), particularly rural Appalachia (RR = 1.28 [95%CI, 1.25-1.301), was elevated. CONCLUSIONS: Cancer incidence in Appalachia was not found to be elevated. However, incidence of cancer of the lung/bronchus, colon, rectum, and cervix was elevated in Appalachia. The rates of unstaged cancer of every examined site were elevated in rural Appalachia, suggesting a lack of access to cancer health care.  相似文献   
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CONTEXT: There is a need for community-based, culturally sensitive, cognitive-behavioral interventions to reduce sexual risk behavior among minority adolescents. Studies of adolescent risk and protective behaviors have focused on identifying modifiable psychosocial variables that predict differential outcomes for subsequent intervention efforts. Research has been scarce in studies of rural minority adolescent women. PURPOSE: To examine the protective and risk behaviors of these rural Mexican-American adolescent women and their relationship to physical or sexual abuse. METHODS: Mexican-American adolescent women aged 14-19 years were recruited through a rural health clinic and administered a self-report assessment for protective and risk behavior and sexual, physical, and psychological abuse. FINDINGS: Rural minority adolescent women endured high levels of psychological distress and many risk behaviors yet experienced few protective behaviors. Barriers to health care included access and confidentiality. Physically or sexually abused adolescents endured relatively greater risk and fewer protective behaviors than nonabused. CONCLUSIONS: Rural Mexican-American adolescent women may benefit from confidential identification and assessment of abuse history and risk and protective behaviors so that appropriate psychological treatment can accompany accessible medical treatment. The prevalence of risk behaviors and abuse among these women presents a need for development of behavioral interventions for risk reduction and promotion of health protective behaviors.  相似文献   
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OBJECTIVE: Antenatal perineal massage has been shown to reduce the incidence of perineal tears in primiparous women. The aim of this study was to determine whether perineal massage impacts on primary prevention of symptomatic disruption of the fecal continence mechanism. METHODS: An observational study recruited two cohorts of women. The first, massage group (MG) chose to perform daily perineal massage from 34 weeks gestation, and the second, control group (CG) was asked to avoid massage. Perineal injury and postnatal pain were documented and all women were invited to attend at three months postpartum for continence assessment, anal manometry, and endoanal ultrasound. RESULTS: Of 179 women recruited, 100 were in the MG while 79 women were controls. Mode of delivery was not influenced by perineal massage. Although the impact did not reach statistical significance, women aged over 30 years in the MG were more likely to be delivered with an intact perineum than controls. Postnatal perineal pain was much reduced in the MG compared with the CG (p = 0.029). Of the women recruited, 136 (75.9%) returned for a postnatal continence assessment. Manometry pressures, continence scores, and endoanal ultrasound findings were similar in both groups. CONCLUSION: Antenatal perineal massage was found to significantly affect postnatal perineal pain scores although it did not impact on the incidence of intact perineum at delivery, postnatal continence scores, anal manometry pressures, or endoanal ultrasound findings.  相似文献   
105.
(1) The methylxanthine caffeine has many pharmacological effects, most of which can be linked to blockade of adenosine receptors, inhibition of phosphodiesterases, and augmentation of calcium-dependent release of calcium from intracellular stores. (2) A variety of xanthines have been developed as potent and/or selective antagonists for adenosine receptors. (3) Several xanthines have been developed that are more potent and more selective inhibitors of cyclic nucleotide phosphodiesterase than caffeine or theophylline. (4) Caffeine remains the xanthine of choice for activation of intracellular calcium-sensitive calcium release channels although millimolar concentrations are required, which can have effects on other aspects of calcium regulation.  相似文献   
106.
OBJECTIVE: Evidence suggests that the in utero environment may contribute to subsequent development of cancers in childhood and adulthood. Raised levels of estrogen during pregnancy may be the primary in utero etiologic factor. Mothers of twins have higher estrogen levels during pregnancy than mothers of singletons, therefore, assessment of cancer risk in twins may be informative.METHOD: We conducted a retrospective cohort study of cancer among twin and singleton newborns selected from the Utah Population Database, matched on birth year and sex. Cancer diagnoses were determined by linkage with the Utah state cancer register. Relative rates of all cancers in childhood and in adulthood in twins compared with singletons, and for specific cancers including testicular, breast and melanoma, were calculated using Poisson regression.RESULTS: Twin (35,271) and singleton (74,199) births were identified, among whom there were 336 and 691 cancer diagnoses, respectively. The relative risk (RR) of childhood cancer in twins compared with singletons was 0.82 [95% confidence interval (CI) 0.55-1.24] and of adult cancer was 1.06 (0.92-1.22). We found nonsignificant increases in risk among adult twins for cancers of the breast, prostate, testis, lymphatic system, thyroid, and large bowel. The largest departures from unity were for testicular cancer (RR 1.47; 95% CI, 0.73-2.95) and melanoma (RR 0.67; 95% CI, 0.42-1.06).CONCLUSIONS: These results are consistent with the body of evidence suggesting that twins have a reduced risk of cancer in childhood. Although there is no overall differential in adult cancer risk, these data support the hypothesis that the in utero environment may play an important role in specific cancers.  相似文献   
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There is a well‐documented shortage of physician researchers, and numerous training programs have been launched to facilitate development of new physician scientists. Short‐term research training programs are the most practical form of research exposure for most medical students, and the summer between their first and second years of medical school is generally the longest period they can devote solely to research. The goal of short‐term training programs is to whet the students’ appetite for research and spark their interest in the field. Relatively little research has been done to test the effectiveness of short‐term research training programs. In an effort to examine short‐term effects of three different NIH‐funded summer research training programs for medical students, we assessed the trainees’ (N = 75) research self‐efficacy prior to and after the programs using an 11‐item scale. These hands‐on training programs combined experiential, didactic, and mentoring elements. The students demonstrated a significant increase in their self‐efficacy for research. Trainees’ gender, ranking of their school, type of research, and specific content of research project did not predict improvement. Effect sizes for different types of items on the scale varied, with the largest gain seen in research methodology and communication of study findings.  相似文献   
110.
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