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131.
A structured interview conducted during the postpartum hospitalization of 184 patients aged 17 years or younger was used to study teenagers' perceptions of barriers to prenatal care. The interview consisted of more than 100 questions on demographic characteristics, family and social support, desire for the pregnancy, perceptions of the importance of prenatal care, practical obstacles to access to health care (such as lack of transportation, day care, etc), financial problems related to care, problems finding time to obtain health care, knowledge of available prenatal care resources, and perceptions of ease or difficulty in the use of existing clinics. Multiple regression analysis using the Kessner index as the criterion variable showed that major factors related to the adequacy of prenatal care received by these teenagers were perceptions of cost barriers, the gestational age at which the teenager discovered she was pregnant, school enrollment status (those in school received poorer care than those who had dropped out), and the degree of social support experienced by the teenager. These findings suggest that specific changes in the health care system are needed to make prenatal care more accessible for pregnant teenagers. These changes would include enhancing community awareness that Medicaid pays for prenatal care, establishing links between prenatal clinics and school health systems, and scheduling prenatal clinics at times more convenient for teenagers.  相似文献   
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BACKGROUND: An artificial anal sphincter has been developed which aimed to simulate the normal physiology of the anorectum. As a prelude to human implantation the present study reports the effect of inflation of this device on colonic perfusion in patients undergoing colectomy, which was assessed by using a laser Doppler scanner. METHODS: Eleven patients (median age 49.8 (range 24.3-78.7) years) were studied. Five patients had inflammatory bowel disease (IBD). The neosphincter was placed around the bowel and progressively inflated. The model was designed so that blood flow changes to the colon under the neosphincter would be reflected in the distal segment of the bowel, which could be scanned by the laser Doppler scanner. RESULTS: The blood flow in the colon distal to the device was significantly higher in patients with IBD (mean(s.e.m.) 288.6(71.9) versus 211.1(57.6) perfusion units; P < 0.001). The mean(s.e.m.) 'biological zero' value was 46(14) perfusion units. Blood flow distal to the neosphincter decreased progressively with increased sphincteric compression by 0.66 per cent per mmHg applied pressure in controls and 0.35 per cent per mmHg in patients with IBD (P < 0.05). CONCLUSION: These results suggest that at the planned operating occlusion pressure (less than 45 mmHg) this neosphincter should not put the vascularity of the human colon at risk.  相似文献   
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The present study investigated the effects of a unit of instruction in mental health on rural adolescents' conceptions of mental illness and their attitudes about seeking professional help for emotional problems. Forty students enrolled in a rural Mississippi high school participated. Twenty were designated as the treatment group and twenty served as the control group. Results indicated that scores on both dependent variables (attitudes about seeking professional help and conceptions of mental illness) increased significantly for the treatment group and, further, these scores did not decrease significantly when the students were tested again twelve weeks later. The findings are discussed in the context of educating rural youth about mental illness with the express purpose of removing the stigma associated with the help-seeking process.  相似文献   
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Persons with various forms of albinism frequently have misrouting of their optic nerve fibers. Visual evoked potential (VEP) studies can confirm this because monocular stimulation tends to result in asymmetrical rather than symmetrical occipital response. This type of decussation abnormality is associated only with albinism. In the electroencephalogram (EEG) of normal subjects, unilateral eye opening or closing does not affect the frequency, reactivity, regulation, and symmetry of alpha rhythm. In contrast, in our study, 6 of 19 persons with oculocutaneous and ocular albinism responded to unilateral eye opening with contralateral disappearance or significant attenuation of their alpha rhythm. The most likely explanation of this phenomenon is that the visual pathway misrouting is complete or nearly complete in some children with albinism so that one rather than both occipital lobes receive visual information from each eye. This type of alpha behavior, like VEP studies, supports the diagnosis of albinism, and such testing can be easily performed during a routine EEG recording.  相似文献   
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A new approach for the modification of the heptapeptide core of glycopeptide antibiotics was proposed based on the replacement of amino acid residues in positions 1 and 3 in teicoplanin aglycone and in position 1 in the eremomycin aglycone. Six novel nonnatural aglycones of the vancomycin type were obtained. Compounds derived from the teicoplanin aglycone exhibited in vitro activity against Gram-positive bacteria, and two of them were also active against the vancomycin-resistant enterococci.  相似文献   
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Although activated CD4+ T cells have been implicated in the pathogenesis of asthma, the direct contribution of this leukocyte to the induction of aeroallergen-induced bronchial hyperreactivity and lung damage is unknown. In the present investigation, we have used a model of allergic airways inflammation, which displays certain phenotypic characteristics of late-phase asthmatic responses, together with interleukin-5-deficient (IL-5-/- ) mice and donor antigen-specific CD4+ TH2-type cells to obtain unequivocal evidence for a role of this T lymphocyte in the pathophysiology of allergic airways inflammation. Antigen-primed CD4+ T cells and CD4- cells (CD4+-depleted population) were purified from the spleens of ovalbumin (OVA)-sensitized wild-type mice and adoptively transferred to OVA-sensitized and nonsensitized IL-5-/- mice. In vitro stimulation of the purified cell populations with OVA resulted in the secretion of IL-4 and IL-5, but not interferon-gamma, from the CD4+ T cells, indicating that they were of the TH2 type. In contrast, interferon-gamma, but not IL-4 and IL-5, was produced by the CD4- T cells. The CD4+ TH2-type cells (but not the CD4 cells) reconstituted aeroallergen (OVA)-induced blood and airways eosinophilia, lung damage, and airways hyperreactivity to 1-methacholine in IL-5-/- mice. The reconstitution did not require prior sensitization of the mice, but it did not occur if they were aerosolized with saline instead of OVA. The circulating levels of OVA-specific -IgE and -IgG1 were not significantly altered by the adoptive transfer of either cell population. These investigations establish that IL-5-secreting CD4+ TH2-type cells play a pivotal role in generating blood and airways eosinophilia and in the subsequent development of bronchial hyperreactivity and lung damage that occurs in response to aeroallergens.  相似文献   
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