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81.
82.
This study investigated relationships between child/parent dissatisfaction with child facial appearance and the self-concept/social competence of 8- to 15-year-old children with (N = 34) and without (N = 34) oral clefts. Children in both groups had normative psychosocial adjustment, but also reported moderate dissatisfaction with facial appearance. Cleft group parents were more likely to agree with their child's dissatisfaction. When cleft group parents were more dissatisfied with child facial appearance, their children reported better quality of life. Results suggest that parents of children with clefts reporting greater dissatisfaction may respond in positive ways that enhance quality of life.  相似文献   
83.
Daily postpartum separations from the litter produce enduring changes in anxiety and sensitivity to the antinociceptive effects of morphine in Long-Evans dams. We tested whether postpartum experience alters sensitivity to the effects of morphine on locomotor activity. Dams were tested 4-6 weeks after their pups were weaned, and had one of the following backgrounds: daily separation from the litter on postpartum days 2-14 for either 3 h (prolonged separation-LS) or 15 min (brief separation-BS), or no separation (nonhandled control-NH). After 2 consecutive days (B1-2) of baseline activity measurements, subjects were tested daily after s.c. injections of either morphine (10 mg/kg) or saline for 7 days and again on day 10. Beginning 5 days later, saline and 1.0-10 mg/kg of morphine were tested in all dams. On B1, LS and BS dams habituated slower than NH controls, yielding higher horizontal counts. LS dams failed to habituate across baseline days and were more active than other dams on B2. Sensitization, a progressive increase in horizontal activity, was more rapid and robust in LS and BS dams compared to NH animals. LS was the only group that developed tolerance to morphine-induced decreases in vertical activity. In LS dams with the history of morphine treatment, injection of saline resulted in higher horizontal activity and center time compared to saline-treated counterparts, indicative of conditioning. Among animals with a history of saline treatment, LS dams were more sensitive to morphine challenges than BS and NH dams. As a result of the robust and long-lasting increases in the ability of morphine to induce behavioral sensitization in litter-separated dams, periodic postpartum separation may represent a new animal model of increased vulnerability to substance abuse.  相似文献   
84.
Cytotoxic T lymphocytes (CTL) recognize antigens derived from endogenously expressed proteins presented on the cell surface in the context of major histocompatibility complex (MHC) class I molecules. Because CTL are effective in antiviral and antitumor responses, the delivery of antigens to the class I pathway has been the focus of numerous efforts. Generating CTL by immunization with exogenous proteins is often ineffective because these antigens typically enter the MHC class II pathway. This review focuses on the usefulness of bacterial toxins for delivering antigens to the MHC class I pathway. Several toxins naturally translocate into the cytosol, where they mediate their cytopathic effects, and the mechanisms by which this occurs has been elucidated. Molecular characterization of these toxins identified the functional domains and enabled the generation of modified proteins that were no longer toxic but retained the ability to translocate into the cytosol. Thus, these modified toxins could be examined for their ability to carry peptides or whole proteins into the cytosolic processing pathway. Of the toxins studied—diphtheria, pertussis, Pseudomonas, and anthrax—the anthrax toxin appears the most promising in its ability to deliver large protein antigens and its efficiency of translocation.  相似文献   
85.
The random dot stereogram E (RDE) has been shown to be a simple and effective test for the detection of binocular abnormalities and defective visual acuity in children. We determined the validity of the RDE as a screening test for reduced visual acuity, amblyopia and strabismus in two separate populations of children.
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening.  相似文献   
86.
87.
Background: Septic shock is associated with vasopressin deficiency and a hypersensitivity to its exogenous administration. The goal of the current study was to determine whether short-term vasopressin infusion in patients experiencing severe septic shock has a vasopressor sparing effect while maintaining hemodynamic stability and adequate end-organ perfusion.

Methods: Patients experiencing septic shock that required high-dose vasopressor support were randomized to a double-blinded 4-h infusion of either norepinephrine (n = 11) or vasopressin (n = 13), and open-label vasopressors were titrated to maintain blood pressure. To assess end-organ perfusion, urine output and creatinine clearance, gastric mucosal carbon dioxide tension, and electrocardiogram ST segment position were measured.

Results: Patients randomized to norepinephrine went from a median prestudy norepinephrine infusion of 20.0 [mu]g/min to a blinded infusion of 17.0 [mu]g/min at 4 h, whereas those randomized to vasopressin went from a median prestudy norepinephrine infusion of 25.0 [mu]g/min to 5.3 [mu]g/min at 4 h (P < 0.001). Mean arterial pressure and cardiac index were maintained in both groups. Urine output did not change in the norepinephrine group (median, 25 to 15 ml/h) but increased substantially in the vasopressin group (median, 32.5 to 65 ml/h;P < 0.05). Similarly, creatinine clearance did not change in the norepinephrine group but increased by 75% in the vasopressin group (P < 0.05). Gastric mucosal carbon dioxide tension and electrocardiogram ST segments did not change significantly in either group.  相似文献   

88.
89.
This study compares the characteristics of general practitioners and a pen and paper test in the detection of psychiatric disorder in primary care settings. A psychiatrist interviewed a stratified sample of 283 patients drawn from 590 consecutive new illnesses seen in 15 general practices. Research diagnoses could be made in between one-quarter and one-third of the consecutive new illnesses. Two different research diagnostic systems agreed quite well with one another about who should be regarded as a psychiatric 'case' - although agreement between them for individual diagnoses was less impressive. Research diagnoses of psychiatric illnesses could be made in approximately 30% of new episodes of illnesses seen. If the DSM-3 system was used as a criterion of 'caseness', the specificity of the general health questionnaire was 75.4%, and the sensitivity was 87.1%. The general practitioners had fewer false positives than the questionnaire, but they were much more likely to miss psychiatric cases. Use of the general health questionnaire could increase their sensitivity from about 50% to 95%.  相似文献   
90.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms.  相似文献   
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