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1.
Summary Parental care was analyzed separately with the PBI for both father and mother or their surrogate to assess its association with suicidal behavior (attempt or serious ideation). The study was conducted on two French-speaking samples from Montreal: the first included 2,327 high school students and the second 701 young adults (18 to 24) reached by phone. Results showed poor care of father to be highly associated with suicidal behavior in the highschool group. Poor care of the mother and parental divorce obtained a lower association. In the second sample, only poor care of the father was significantly associated with suicidal behavior. The conclusion is that more attention should be focused on the father and that parental divorce may have a short-term effect but not a lasting influence when poor care is absent.  相似文献   
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C Bastien  K Campbell 《Sleep》1992,15(3):236-245
The functional significance and topographical variation of the different components of the evoked K-complex were examined. In the first experiment, the intensity of the stimulus (80 and 60 dB SPL) and its rise-and-fall time (2 and 20 milliseconds) were manipulated during nonrapid eye movement sleep. In the second experiment the tonal frequency (500, 1,000 and 2,000 Hz) of the stimulus was manipulated. In the first experiment, nine stimuli were presented every 10 seconds, whereas in the second, 20 consecutive stimuli were presented. The evoked K-complex consisted of two different negative components peaking at approximately 350 and 550 milliseconds, respectively, and followed by a positive component peaking at approximately 900 milliseconds. K-complexes were easier to elicit for high-intensity fast rise-and-fall time stimuli than for low-intensity slow rise-and-fall time stimuli. The probability of occurrence was not affected by the tonal frequency of the stimulus. When a K-complex was evoked, the amplitude and latency of N350, N550 and P900 remained invariant regardless of its intensity, rise-and-fall or its tonal frequency. The N550-P900 portion of the K-complex therefore appears to be an all-or-none phenomenon. On trials in which a K-complex could not be elicited, N350 was still visible although much attenuated. In these trials, its amplitude was further reduced when stimulus intensity was lowered. N350 might need to reach a certain critical threshold before the much larger N550-P900 complex is elicited.  相似文献   
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Summary A case is described of symmetrical cavitating brain stem necrosis produced by cardiac arrest in a premature infant. Two months after birth this 25-week gestational age infant suffered a prolonged episode of bradycardia. She was resuscitated and then died 3 weeks later. The autopsy revealed striking bilateral cavitation of the brain stem tegmentum extending in a columnar fashion from the upper portion of the spinal cord to the hypothalamus. The findings in this case are identical to the brain stem injury experimentally produced by complete cardiac arrest in the rhesus monkey.  相似文献   
5.
目的评价温泉浮游生物纯提取物(pureextractthermalplankton,PETP)即线状透明颤菌(Vitreoscillafiliformis,VF)提取物用于中国女性敏感性皮肤的功效与耐受性。方法经临床检查和乳酸刺激实验筛选出伴有敏感性皮肤的健康女性36例。早晚清洁面部后,均匀涂抹1%VF面霜,每日2次,连续使用3周。分别于实验前后由同一个皮肤科医师观察受试者的皮肤乳酸刺激分数,以及皮肤的临床表现(干燥、红斑、鳞屑、弹性、光滑度)。同时,检测皮肤颜色及皮肤角质层水合度等皮肤生物学参数。结果受试者的乳酸刺激分数显著降低,使用前后差异显著(P<0.0001)。干燥、红斑、鳞屑、光滑度均有不同程度改善。受试者对VF面霜耐受良好。结论伴有敏感性皮肤的中国女性,在皮肤日常护理中,使用含有VF提取物的护肤品有助于改善皮肤的敏感状态和皮肤保健。  相似文献   
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Molecular methods for the rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) are generally based on the detection of an S. aureus-specific gene target and the mecA gene. However, such methods cannot be applied for the direct detection of MRSA from nonsterile specimens such as nasal samples without the previous isolation, capture, or enrichment of MRSA because these samples often contain both coagulase-negative staphylococci (CoNS) and S. aureus, either of which can carry mecA. In this study, we describe a real-time multiplex PCR assay which allows the detection of MRSA directly from clinical specimens containing a mixture of staphylococci in <1 h. Five primers specific to the different staphylococcal cassette chromosome mec (SCCmec) right extremity sequences, including three new sequences, were used in combination with a primer and three molecular beacon probes specific to the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. Of the 1,657 MRSA isolates tested, 1,636 (98.7%) were detected with the PCR assay, whereas 26 of 569 (4.6%) methicillin-susceptible S. aureus (MSSA) strains were misidentified as MRSA. None of the 62 nonstaphylococcal bacterial species or the 212 methicillin-resistant or 74 methicillin-susceptible CoNS strains (MRCoNS and MSCoNS, respectively) were detected by the assay. The amplification of MRSA was not inhibited in the presence of high copy numbers of MSSA, MRCoNS, or MSCoNS. The analytical sensitivity of the PCR assay, as evaluated with MRSA-negative nasal specimens containing a mixture of MSSA, MRCoNS, and MSCoNS spiked with MRSA, was approximately 25 CFU per nasal sample. This real-time PCR assay represents a rapid and powerful method which can be used for the detection of MRSA directly from specimens containing a mixture of staphylococci.  相似文献   
9.
BACKGROUND: Ingestion of small amounts of an offending food can elicit adverse reactions in individuals with IgE-mediated food allergies. The threshold dose for provocation of such reactions is often considered to be zero. However, because of various practical limitations in food production and processing, foods may occasionally contain trace residues of the offending food. Are these very low, residual quantities hazardous to allergic consumers? How much of the offending food is too much? Very little quantitative information exists to allow any risk assessments to be conducted by the food industry. OBJECTIVE: We sought to determine whether the quality and quantity of existing clinical data on threshold doses for commonly allergenic foods were sufficient to allow consensus to be reached on establishment of threshold doses for specific foods. METHODS: In September 1999, 12 clinical allergists and other interested parties were invited to participate in a roundtable conference to share existing data on threshold doses and to discuss clinical approaches that would allow the acquisition of that information. RESULTS: Considerable data were identified in clinical files relating to the threshold doses for peanut, cows' milk, and egg; limited data were available for other foods, such as fish and mustard. CONCLUSIONS: Because these data were often obtained by means of different protocols, the estimation of a threshold dose was very difficult. Development of a standardized protocol for clinical experiments to allow determination of the threshold dose is needed.  相似文献   
10.
Patterns of linkage disequilibrium (LD) in the human genome are beginning to be characterized, with a paucity of haplotype diversity in "LD blocks," interspersed by apparent "hot spots" of recombination. Previously, we cloned and physically characterized the low-density lipoprotein-receptor-related protein 5 (LRP5) gene. Here, we have extensively analysed both LRP5 and its flanking three genes, spanning 269 kb, for single nucleotide polymorphisms (SNPs), and we present a comprehensive SNP map comprising 95 polymorphisms. Analysis revealed high levels of recombination across LRP5, including a hot-spot region from intron 1 to intron 7 of LRP5, where there are 109 recombinants/Mb (4882 meioses), in contrast to flanking regions of 14.6 recombinants/Mb. This region of high recombination could be delineated into three to four hot spots, one within a 601-bp interval. For LRP5, three haplotype blocks were identified, flanked by the hot spots. Each LD block comprised over 80% common haplotypes, concurring with a previous study of 14 genes that showed that common haplotypes account for at least 80% of all haplotypes. The identification of hot spots in between these LD blocks provides additional evidence that LD blocks are separated by areas of higher recombination.  相似文献   
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