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91.
A national household probability sample of 4,023 adolescents aged 12 to 17 years was surveyed by telephone via structured clinical interview to determine the impact of familial substance use, sexual and physical assault, witnessed violence, depression and posttraumatic stress disorder (PTSD) on risk of smoking. Results indicated that familial substance use increased risk of smoking only for boys and sexual assault or depression increased risk of smoking only for girls. Age, Caucasian ethnicity, and experiencing physical assault or witnessing violence elevated risk of current cigarette use for both genders. By contrast, PTSD per se was not associated with increased risk of smoking, after the effects of other variables were controlled.  相似文献   
92.
In a prospective two-centre study targeted US was performed as an adjunct to mammography in a population of 1103 patients with 272 breast cancers, 517 benign lesions and no abnormalities in 314 patients. The purpose of the study was to analyse the distribution of the different US variables among the breast lesions and to determine the prognostic value of these variables with respect to the diagnosis of malignancy. The following variables were analysed: border; contour; orientation; structure; echogenicity; sound transmission; and size. These variables were correlated with the definitive diagnosis and univariate analysis was performed. A statistically significant association with breast cancer (p < 0.001) was present for irregular border; ill-defined contour; indeterminate or vertical orientation; homogeneous, complex or heterogeneous structure; hypoechogenicity; and unchanged or decreased sound transmission. Multivariate analysis showed a high independent prognostic value for malignancy for irregular border, followed by ill-defined contour and unchanged or decreased sound transmission. However, their discriminative power was not absolute: in 38 cancers none of the malignant US variables were present, and in 11 benign lesions all variables were present. There were hardly any benign-looking lesions that proved to be malignant. Received: 6 October 1999; Revised: 3 March 2000; Accepted: 26 June 2000  相似文献   
93.
OBJECTIVE: Over 3% of infants born annually in the United States are from a multiple gestation pregnancy, yet there is little data published about the feeding practices of their mothers. The objectives of this study were to determine and compare the rates of breast milk feeding of mothers of multiples and mothers of singletons. METHODS: Stratified random sampling (n = 686) on the basis of plurality of pregnancy and gestational age at delivery was performed on a 1999 birth certificate database in the greater Cincinnati area. We collected information about infant feeding during the first 6 months of life using a retrospective, self-administered questionnaire and phone interview from mothers of term singletons (TS), preterm singletons (PS), term multiples (TM), and preterm multiples (PM). Data were analyzed using chi-square and logistic or multiple regression. RESULTS: We obtained feeding information from 346 mothers (n = 81 TS, 80 PS, 90 TM, and 95 PM). By 3 days postpartum, PM provided breast milk less often than all other groups: TS = 69%, PS = 66%, TM = 73%, PM = 57% (P =.035). Among mothers who initiated breast milk feeding, the geometric mean duration of at least some breast milk feeding was significantly shorter for PM than for all other groups: TS = 23 weeks, PS = 19 weeks, TM = 24 weeks, and PM = 12 weeks (P =.002). CONCLUSIONS: Further evaluation of the potential causes for the lower breast milk feeding rates among PM is needed to develop effective intervention strategies and increase the number of preterm multiple gestation infants receiving breast milk.  相似文献   
94.
The endogenous cannabinoid system is a relatively novel discovered system consisting of cannabinoid CB1 receptors, which are expressed both in the periphery and in the central nervous system, peripheral cannabinoid CB2 receptors and endogenous cannabinoids, which are anandamide and 2-arachidonyl glycerol. The cannabinoid CB1 receptors have recently been implicated in rewarding aspects of not only the cannabinoid drug Delta9-tetrahydrocannabinol (Delta9-THC), but also of other drugs of abuse, including cocaine. The present study was designed to further investigate the role of CB1 receptors in reward-related effects of cocaine. Using the CB1 receptor selective antagonist SR141716A, the involvement of CB1 receptors in cocaine reinforcement was determined by intravenous cocaine self-administration. In addition, the effects of the CB1 receptor selective antagonist SR141716A upon the development of cocaine-induced behavioural sensitization were investigated. SR141716A did not affect cocaine reinforcement nor did it affect the development of behavioural sensitization to the locomotor stimulant effects of cocaine. These findings suggest that CB1 receptors are not involved in acute cocaine reinforcement nor in cocaine-induced behavioural sensitization.  相似文献   
95.
96.
The epithelium of the human breast is made up of a branching ductal–lobular system, which is lined by a single layer of luminal cells surrounded by a contractile basal cell layer. The co-ordinated development of stem/progenitor cells into these luminal and basal cells is fundamentally important for breast morphogenesis. The ovarian steroid hormones, progesterone (P) and 17β-estradiol, are critical in driving this normal breast development, yet ovarian activity has also been shown to be a major driver of breast cancer risk. We previously demonstrated that P treatment increases proliferation and augments the number of progenitor-like cells, and that the progesterone receptor (PR) is also expressed in the bipotent progenitor-enriched subfraction. Here we demonstrate that PR is expressed in a subset of CD10+ basal cells and that P stimulates this CD10+ cell compartment, which is enriched for bipotent progenitor activity. In addition, we have shown that P stimulates progenitor cells in human breast cancer cell lines and expands the cancer stem cell population via increasing the stem-like CD44+ population. As changes in cell type composition are one of the hallmark features of breast cancer progression, the demonstration that progenitor cells are stimulated by P in both normal breast and in breast cancer cells has critical implications in discerning the mechanisms of how P increases breast cancer risk.  相似文献   
97.
98.
Studies in the Scandinavian countries have shown that orthodontists run an equal or even greater risk of contracting dermatitis compared to other dental personnel. The aim of the study was to find out whether the self-reported occupation-related health problems of general dental practitioners and orthodontists differ from those of office employees in Finland. The subjects were 147 general dentists, 81 orthodontists and 99 office employees (77% women and 23% men). The data were collected using a mailed questionnaire. Within the past year, 42% of the subjects had had occupational health problems, while 51% had experienced symptoms in the previous year or earlier. The complaints of hand dermatoses, musculoskeletal, as well as respiratory symptoms were significantly more common among women than among men. Musculoskeletal complaints were the most common symptoms in all occupational groups, but the odds ratio of having them were significantly higher for dental professionals compared to office employees. The frequency of self-reported hand dermatoses was 42% for dental professionals and 26% for office employees, but the difference did not reach statistical significance. The odds of having hand dermatoses were higher for atopic subjects and for women. Orthodontists did not differ from general practitioners in respect of any of the complaints reported. Materials used in dentistry were mentioned as the cause of symptoms by 49 (21.5%) of the dental professionals. The present results show an increased risk of self-reported musculoskeletal symptoms for the dental professionals. Also, a tendency towards increased occurrence of skin symptoms was noted for the dental professionals compared to office employees of this study.  相似文献   
99.
100.
Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) is present in 30–60 % of HIV-positive (HIV+) individuals and can be assessed by neuropsychological testing and level of functional impairment. HAND diagnosis therefore requires accurate assessment of functional impairment. The Computer Assessment of Mild Cognitive Impairment (CAMCI) is a computer-based screening tool that includes performance-based measures of functional impairment. We sought to evaluate the CAMCI as a functional assessment tool in HAND. One hundred fourteen HIV+ patients and 38 HIV-negative (HIV?) patients underwent neuropsychological and CAMCI testing. Cognitive status for HIV+ subjects was classified using the Frascati criteria. HIV+ subjects grouped together and classified by cognitive impairment performed worse than HIV? subjects on several of the CAMCI tasks, including following directions to the supermarket (p?=?0.05, p?=?0.03), recalling which items to purchase (p?=?0.01, p?=?0.02), and remembering to stop at a supermarket (p?<?0.01, p?=?0.01) and the post office (p?<?0.01, p?=?0.03). After controlling for hepatitis C status and depression symptomatology, the tasks “following directions to the supermarket” and the “recalling which items to purchase” were no longer significant. The “remembering to run two separate errands” tasks retained their significance (p?<?0.01 for both tasks). A subset of the CAMCI tasks therefore successfully differentiated HIV+ patients from HIV? individuals. Differences in hepatitis C status and depression symptomatology could account for some of the function assessment differences in the CAMCI. These results suggest the CAMCI could be a useful objective performance-based functional assessment in patients with HIV.  相似文献   
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