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51.
BACKGROUND: Although gender differences have been noted in the risk factors for suicide and attempted suicide, comparative studies to date have used only 2 groups and a limited number of measures. The present study compared the effect of gender on suicide among 4 groups of psychiatrically hospitalized adolescents using a cross-sectional design. METHODS: The study sample consisted of 404 patients, aged between 12 and 21, who were divided into 4 groups: 76 male suicide attempters, 103 male nonattempters, 143 female suicide attempters, and 82 female nonattempters. Patients were tested for life events, affective disorders, aggression, impulsivity, ego defense mechanisms, and death perception with the Child Suicide Potential Scale, Beck Depression Inventory, State-Trait Anxiety Inventory, Overt Aggression Scale, Multidimensional Anger Inventory, Impulsivity Control Scale, and Life Style Index. Findings were analyzed by multivariate regression with stepwise logistic models. RESULTS: Depression and anxiety were more prevalent in female nonattempters than in male nonattempters; there were no such gender differences among the attempters. Antisocial behavior was more prevalent in male attempters than in female attempters; there were no gender differences on this aspect among the nonattempters. There were gender differences for defense mechanisms in the attempters. Logistic regression models for men and women separately revealed that antisocial behavior and anxiety were common predictors of suicide attempt, that destructiveness was a predictor in women only, and that depression was associated with suicide attempt in men only. CONCLUSIONS: Suicide-prone female and male adolescent inpatients show distinct differences in psychopathology, ego defense mechanisms, and life events compared to psychiatrically hospitalized adolescents without any history of suicide attempt. Any deviation from a gender-specific behavior must raise suspicion of a risk of attempted suicide.  相似文献   
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The use of services for mental problems is generally reported as being relatively low. However, the methods used for data collection in surveys may have influenced the quality of self-reported service use. This study compares the information on recourse to physicians for mental problems reported in different sections of a survey conducted in six European countries. Thus, 5545 respondents were asked questions on contacts with physicians at least twice: (1) after the symptoms checklist in any completed diagnostic section, and (2) in a section devoted to use of care for mental problems. Of these 39.3% reported contacts with physicians about mental problems in the diagnostic sections, whereas 29.5% did so in the use-of-care section. Inconsistencies concerned 20.1% of participants, among whom those reporting consultations in diagnostic sections without reporting them in the use-of-care section represented the majority (74.4%). Multiple logistic regression analysis revealed that age, marital status, educational level and country were associated with under-reporting in the use-of-care section, as well as having mood or sleep problems. In conclusion, services used for mental health reasons when measured through a question referring to use of care due to the presence of a mental problem may underestimate the care people received for their problems.  相似文献   
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PURPOSE: To measure circulating antigens, sandwich ELISA assays require two complementary affinity reagents. Mouse monoclonal antibodies (mAb) and polyclonal antibodies (pAb) are commonly used, but because their production is lengthy and costly, recombinant antibodies are emerging as an attractive alternative. EXPERIMENTAL DESIGN: We developed a new class of recombinant antibodies called biobodies (Bb) and compared them to mAb for use in serodiagnosis. Bbs were secreted biotinylated in vivo by diploid yeast and used as affinity reagents after Ni purification. Bead-based assays for HE4 and mesothelin were developed using Bbs in combination with pAbs (Bb/pAb assays). To assess precision, reproducibility studies were done using four runs of 16 replicates at six analyte levels for each marker. Pearson correlations and receiver-operator characteristic analyses were done in 214 patient serum samples to directly compare the Bb/pAb assays to mAb assays. Diagnostic performance of the Bb/pAb assay was further assessed in an expanded set of 336 ovarian cancer cases and controls. RESULTS: On average across analyte levels, Bb/pAb assays yielded within-run and between-run coefficients of variations of 11.7 and 23.8, respectively, for HE4 and 14.0 and 14.5, respectively, for mesothelin. In the subset (n = 214), Pearson correlations of 0.95 for HE4 and 0.92 for mesothelin were observed between mAb and Bb/pAb assays. The area under the curves for the mAb and Bb/pAb assays were not significantly different for HE4 (0.88 and 0.84, respectively; P = 0.20) or mesothelin (0.74 and 0.72, respectively; P = 0.38). CONCLUSION: Yeast-secreted Bbs can be used reliably in cost-effective yet highly sensitive bead-based assays for use in large validation studies.  相似文献   
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Methyl tertiary butyl ether (MTBE) is an additive in some formulationsof unleaded gasoline (UG) that enhances octane and reduces carbonmonoxide emissions from motor vehicles. MTBE in CD-I mice andUG in B6C3F1 mice increased the incidence of liver tumors selectivelyin female mice in their chronic bioassays. Both agents werenegative in in vitro tests of genotoxicity, and exhibit similarhepatic microsomal cytochrome P450 activity and hepatocyte proliferationafter short-term exposure. We previously demonstrated that UGhas hepatic tumor-promoting activity in DEN-initiated femaleB6C3F1 mice. Thus, we hypothesized that MTBE would have hepatictumor-promoting activity in the same initiation-promotion modelsystem in which UG was a hepatic tumor promoter. Twelve-day-oldfemale B6C3F1 mice were initiated with a single i.p. injectionof the mutagen N-nitrosodiethylamine (DEN) (5 mg DEN/kg, 7.1ml/kg body weight) or saline. Beginning at 8 weeks of age, micewere exposed to 0 ppm or the hepatocarcinogenic dose of approximately8000 ppm MTBE. After subchronic exposure, MTBE significantlyincreased liver weight and hepatic microsomal cytochrome P450activity without hepa-totoxicity or an increase in non-focalhepatocyte DNA synthesis. These are subchronic effects similarto those produced by UG. However, MTBE did not significantlyincrease the mean size of hepatic foci and volume fraction ofthe liver occupied by foci as compared to DEN-initiated controlsat either 16 or 32 weeks. The lack of tumor-promoting abilityof MTBE in DEN-initiated female mouse liver was unexpected andsuggests that MTBE does not produce liver tumors through a tumor-promotingmechanism similar to that of UG.  相似文献   
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The clinical and echocardiographic manifestations in 25 patients with Marfan's syndrome diagnosed during infancy and childhood (mean [+/- SD] age, 8.1 +/- 4.8 years; range 0 to 16 years) were evaluated. Twenty-one patients (84%) had a midsystolic click, 11 patients (44%) had mitral regurgitation (MR), and five patients (20%) had combined MR and aortic regurgitation (AR). Echocardiography demonstrated mitral valve prolapse in all 25 patients, aortic root dilatation in 20 patients (80%), AR in seven patients (28%), and aortic aneurysm in five patients (20%). During the follow-up period (mean, 5 +/- 4.5 years), progressive AR and aortic aneurysm were documented in four patients, progressive MR in three patients, and progressive aortic root dilatation in two patients. Five patients (22%) died during the follow-up period. Among patients with a positive family history of Marfan's syndrome, MR was less frequent as compared with sporadic cases (29.4% vs 75%, respectively). Progressive cardiovascular involvement was more frequent among patients diagnosed before 10 years of age compared with those diagnosed later (60% vs 12.5%, respectively). Cardiovascular involvement was a common feature of childhood Marfan's syndrome, causing significant morbidity and mortality. Sporadic cases and children diagnosed before 10 years of age represented a particularly high-risk group.  相似文献   
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Membrane cofactor protein (MCP; CD46) is a widely expressed transmembrane complement regulator. Like factor H it inhibits complement activation by regulating C3b deposition on targets. Factor H mutations occur in 10-20% of patients with hemolytic uremic syndrome (HUS). We hypothesized that MCP mutations could predispose to HUS, and we sequenced MCP coding exons in affected individuals from 30 families. MCP mutations were detected in affected individuals of three families: a deletion of two amino acids (D237/S238) in family 1 (heterozygous) and a substitution, S206P, in families 2 (heterozygous) and 3 (homozygous). We evaluated protein expression and function in peripheral blood mononuclear cells from these individuals. An individual with the D237/S238 deletion had reduced MCP levels and approximately 50% C3b binding compared with normal controls. Individuals with the S206P change expressed normal quantities of protein, but demonstrated approximately 50% reduction in C3b binding in heterozygotes and complete lack of C3b binding in homozygotes. MCP expression and function was evaluated in transfectants reproducing these mutations. The deletion mutant was retained intracellularly. S206P protein was expressed on the cell surface but had a reduced ability to prevent complement activation, consistent with its reduced C3b binding and cofactor activity. This study presents further evidence that complement dysregulation predisposes to development of thrombotic microangiopathy and that screening patients for such defects could provide informed treatment strategies.  相似文献   
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