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101.
This study explored premorbid, neurocognitive, behavioral, and familial factors in preschoolers, ages 3-6, who experienced a mild to moderate traumatic brain injury (TBI). Twenty-nine children with TBI, 33 children with mild to moderate injuries to other body regions, and 34 non-injured children participated in the study. Neuropsychological assessments and behavioral measures were administered at the time of hospitalization and 6 months later. In comparison to the non-injury children, preschool-aged children with TBI had higher rates of premorbid behavior difficulties, lower premorbid cognitive functioning, and poorer development of pre-academic skills. In addition, parents of children with TBI reported greater situational issues and life stressors than parents of children in the non-injured group. Some neurocognitive recovery was evident in the TBI group, but no differences were recognized in behavioral and family measures at the 6-month follow-up. This study emphasizes the relative effects of premorbid characteristics in later practice of preschool children who sustain TBI.  相似文献   
102.

Background

Variants in GBA are the most common genetic risk factor for Parkinson's disease (PD), and are especially prevalent in the Ashkenazi Jewish (AJ) population. However, most studies on GBA in AJ genotype only seven selected Gaucher-associated pathogenic variants rather than sequencing the whole gene, which may leave carriers of PD-associated GBA variants undiscovered.

Methods

GBA was fully sequenced using molecular inversion probes (MIPs) and Sanger sequencing in 735 AJ PD patients and 662 AJ controls, from Israel and New York. Additional AJ control data (n?=?3044) from the Inflammatory Bowel Disease Exome Portal was used.

Results

Full GBA sequencing increased the number of variants discovered by 17.4%, compared to targeted genotyping. An additional 17 PD patients were identified with GBA-associated PD. The p.E326K variant was found in 1.6% of AJ PD patients, making it the second most common PD-associated GBA variant in AJ. GBA variants were found in 18% of PD patients and 7.5% of controls (OR?=?2.7, 95%CI?=?1.9–3.8, p?<?0.0001).

Conclusion

Without full sequencing of GBA, or at minimum including p.E326K in the genotyping panel, a significant proportion of variant carriers go undiscovered and may be incorrectly assigned as non-carriers in studies or clinical trials.  相似文献   
103.
Ashdown's medium, Burkholderia pseudomallei selective agar (BPSA), and a commercial Burkholderia cepacia medium were compared for their abilities to grow B. pseudomallei from 155 clinical specimens that proved positive for this organism. The sensitivity of each was equivalent; the selectivity of BPSA was lower than that of Ashdown's or B. cepacia medium.  相似文献   
104.
This study examined risk and protective factors that differentiate low-income, abused African American women (N = 200) who attempted suicide from those who had never made a suicide attempt. Results from multivariate analyses revealed that numerous and/or severe negative life events, a history of child maltreatment, high levels of psychological distress and depression, hopelessness about the future, and alcohol and drug problems were factors associated with attempter status. Protective factors associated with nonattempter status included hopefulness, self-efficacy, coping skills, social support, and effectiveness in obtaining material resources. Culturally competent intervention approaches for abused women should target increasing their protective factors and reducing their risk factors to decrease the likelihood that these women engage in suicidal behavior.  相似文献   
105.
106.
Vaginal swab specimens may be preferable to cervical swab or urine specimens for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae because of the ease of specimen collection and transport. The purpose of this study was to evaluate whether vaginal swab specimens are equivalent to cervical swab specimens for the detection of N. gonorrhoeae and C. trachomatis by the Becton Dickinson strand displacement amplification assay (SDA) with the BDProbeTec ET instrument and then to evaluate the use of the amplification control in a clinical research setting. In the first phase, vaginal and cervical swab specimens were obtained from 455 symptomatic women aged 18 to 40 attending primary health care and sexually transmitted disease clinics. Thirty-nine specimens (8.6%) had true-positive results for N. gonorrhoeae and 37 specimens (8.1%) had true-positive results for C. trachomatis. The sensitivity of SDA was superior to that of culture for the detection of N. gonorrhoeae with vaginal swab specimens and equivalent to that of the Roche PCR for the detection of C. trachomatis with cervical swab specimens. In the second phase of the study, 1,411 consecutively collected vaginal swab specimens were evaluated, with 357 (25.3%) specimens giving indeterminate readings on the basis of the result for the amplification control. The prevalences of sexually transmitted pathogens in vaginal swab specimens with and without use of the amplification control were 6.0 and 5.8%, respectively, for C. trachomatis and 3.1 and 3.0%, respectively, for N. gonorrhoeae. Although, vaginal swab specimens were equivalent to cervical swab specimens for the detection of N. gonorrhoeae and C. trachomatis by SDA with respect to sensitivity, one in four vaginal swab specimens yielded an indeterminate result when the amplification control was used. The amplification control has limited value for use with vaginal swab specimens.  相似文献   
107.
Sera from rabbits with early experimental syphilis were tested for their effect on in vitro lymphocyte transformation responses to related specific antigens (sonicated T. pallidum), unrelated specific antigens (sheep erythrocytes), and the T cell mitogen, concanavalin A. Results were compared with responses in preinfection sera and in sera from sham-infected rabbits. Titration experiments in which normal serum was used indicated that optimal lymphocyte responsiveness is obtained with a final serum concentration of 1%. Under these conditions, no differences in concanavalin A stimulation were observed in cultures with syphilitic sera. Responses to sonicated T. pallidum were inhibited, but only by 17 to 25% when compared with the response in preinfection sera. In cultures containing 10% serum, inhibition of lymphocyte proliferation to sonicated T. pallidum antigens was evident with sera from all syphilitic animals from day 10 (55% inhibition) through day 31 (80% inhibition) of infection. Responses to concanavalin A and sheep erythrocytes were significantly inhibited by day 10 sera; only 20% of the sera tested demonstrated substantial nonspecific inhibitory capacity. No differences were evident among sera from any of the sham-infected animals or among the preinfection sera from either group. Pooled serum with high inhibitory activity was fractionated by ammonium sulfate precipitation, DEAE ion exchange chromatography, and Sephadex G-200 gel filtration. Two separate inhibitors were identified: (i) a low-molecular-weight, ammonium sulfate-soluble, nonspecific inhibitory fraction containing albumin and alpha-globulins with the capacity to inhibit both antigen and mitogen responses and (ii) a high-molecular-weight, ammonium sulfate-precipitable, inhibitory fraction containing alpha-globulin and FTA-ABS-reactive immunoglobulin M which affected only the antigen-specific response to sonicated T. pallidum. Immunodiffusion failed to detect immunoglobulin or T. pallidum antigens in either fraction. DEAE-purified immunoglobulin G from immune serum was not inhibitory.  相似文献   
108.
109.
DNA markers that map within the karyotypically defined band q13 on human chromosome 11 are amplified in a subset of mammary and squamous cell carcinomas. It is assumed that the amplified DNA includes a critical gene (or genes) whose overexpression provides a selective force in the development of the tumor. To help identify such genes, we have begun to construct a physical map of CpG islands in the region, making use of a squamous cell carcinoma cell line (UMSCC2) in which the 11q13 region is amplified 11-fold. We previously described the proximal end of this amplicon and the order of markers extending ~800 kb centromeric of the FGF3 locus (formerly INT2). We now report the use of chromosome jumping techniques to define additional CpG islands that lie distal to FGF3. These map within the amplified region in UMSCC2 cells and the most telomeric corresponds to the EMS1 gene. The data imply that the amplified DNA in UMSCC2 cells extends for over 1,500 kb and includes at least 7 potential genes. EMS1 and CCND1 (formerly PRAD1), the best candidates for the key gene on the 11q13 amplicon, are ≥800 kb apart. © 1993 Wiley-Liss, Inc.  相似文献   
110.
Yersinia enterocolitica is an enteric pathogen that consists of six biotypes: 1A, 1B, 2, 3, 4, and 5. Strains of the latter five biotypes can carry a virulence plasmid, known as pYV, and several well-characterized chromosomally encoded virulence determinants. Y. enterocolitica strains of biotype 1A lack the virulence-associated markers of pYV-bearing strains and were once considered to be avirulent. There is growing epidemiological, clinical, and experimental evidence, however, to suggest that some biotype 1A strains are virulent and can cause gastrointestinal disease. To identify potential virulence genes of pathogenic strains of Y. enterocolitica biotype 1A, we used genomic subtractive hybridization to determine genetic differences between two biotype 1A strains: an environmental isolate, Y. enterocolitica IP2222, and a clinical isolate, Y. enterocolitica T83. Among the Y. enterocolitica T83-specific genes we identified were three, tcbA, tcaC, and tccC, that showed homology to the insecticidal toxin complex (TC) genes first discovered in Photorhabdus luminescens. The Y. enterocolitica T83 TC gene homologues were expressed by Y. enterocolitica T83 and were significantly more prevalent among clinical biotype 1A strains than other Yersinia isolates. Inactivation of the TC genes in Y. enterocolitica T83 resulted in mutants which were attenuated in the ability to colonize the gastrointestinal tracts of perorally infected mice. These results indicate that products of the TC gene complex contribute to the virulence of some strains of Y. enterocolitica biotype 1A, possibly by facilitating their persistence in vivo.  相似文献   
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