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71.
This study investigated how mothers’ attachment was related to their responses to their own and their children’s positive events and positive affect (PA). Ninety-seven mothers reported on their attachment and their responses to their own and their 7–12-year-old children’s positive events and emotions. Children reported on their mothers’ responses to the children’s positive events and their attachment security with their mothers. The results indicated that more avoidant mothers reported less intense PA in response to their own and their children’s positive events. More avoidant mothers also were less likely to encourage their children to savor positive events (through expressing PA, reflecting on PA or themselves, giving rewards, and affectionate responses). Mothers higher on anxiety reported greater likelihood of dampening (e.g., minimizing the event’s importance) their own positive events and reported being more likely to feel discomfort and to reprimand their children for expressing PA. Children’s security was predicted by mothers’ lower likelihood of encouraging children’s dampening and of reprimanding children for PA displays. This study advances the literature on how mothers’ attachment is related to the ways in which they regulate their own and their children’s PA, which may have implications for children’s attachment and developing PA regulation.  相似文献   
72.
The association between MSHR coding region variation and hair colour in humans has been examined by genotyping 25 red haired and 62 non-red Caucasians, all of whom were 12 years of age and members of a twin pair study. Twelve amino acid substitutions were seen at 11 different sites, nine of these being newly described MSHR variants. The previously reported Val92Met allele shows no association with hair colour, but the three alleles Arg151Cys, Arg160Trp and Asp294His were associated with red hair and one Val60Leu variant was most frequent in fair/blonde and light brown hair colours. Variant MSHR genotypes are associated with lighter skin types and red hair (P < 0.001). However, comparison of the MSHR genotypes in dizygotic twin pairs discordant for red hair colour indicates that the MSHR gene cannot be solely responsible for the red hair phenotype, since five of 13 pairs tested had both haplotypes identical by state (with three of the five having both identical by descent). Rather, it is likely that additional modifier genes exist, making variance in the MSHR gene necessary but not always sufficient, for red hair production.   相似文献   
73.
Analysis of the combined effects of polymorphisms in genes encoding xenobiotic metabolizing enzymes (XMEs) and DNA repair proteins may be a key to understanding the role of these genes in the susceptibility of individuals to mutagens. In the present study, we performed an in vitro experiment on lymphocytes from 118 healthy donors that measured the frequency of diepoxybutane (DEB) induced sister chromatid exchanges (SCEs) in relation to genetic polymorphisms in genes coding for XMEs (CYP1A1, CYP2E1, GSTT1, EPHX, and NAT2), as well as DNA repair proteins (XRCC1, XRCC2, XRCC3, XPD, XPA, XPC, XPG, XPF, ERCC1, BRCA1, NBS1, and RAD51). We found that GSTT1(-) and CYP2E1 c1/c2 polymorphisms were associated with higher DEB-induced SCE frequencies, and that NAT2 G(590)A was associated with lower SCE induction by DEB. Analysis of the effect of pairs of genes showed that for a fixed GSTT1 genotype, the SCE level increased with an increasing number of Tyr alleles in EPHX codon 113. We found that among GSTT1(+) individuals the DEB-induced SCE level was significantly lower when the EPHX 139 codon was His/Arg rather than His/His. An interaction between polymorphisms in CYP2E1 and at EPHX codon 113 was also observed. The results of our study confirm observations in cancer patients and in people exposed to xenobiotics indicating that sensitivity to mutagens depends upon a combined effect of a variety of "minor impact" genes. Moreover, our results indicate that polymorphisms in genes coding for XMEs have a greater influence on the genotoxic activity of DEB, measured by DEB-induced SCE frequency, than polymorphisms in genes encoding DNA repair proteins.  相似文献   
74.
We assessed the locomotor capacity of the left half of the spinal cord hindlimb enlargement in low-spinal turtles. Forward swimming was evoked in the left hindlimb by electrical stimulation of the right dorsolateral funiculus (DLF) at the anterior end of the third postcervical spinal segment (D3). Animals were held by a band-clamp in a water-filled tank so that hindlimb movements could be recorded from below with a digital video camera. Left hindlimb hip and knee movements were tracked while electromyograms (EMGs) were recorded from left hip and knee muscles. In turtles with intact spinal cords, electrical stimulation of the right D3 DLF evoked robust forward swimming movements of the left hindlimb, characterized by rhythmic alternation between hip flexor (HF) and hip extensor (HE) EMG discharge, with knee extensor (KE) bursts occurring during the latter part of each HE-off phase. After removing the right spinal hemi-enlargement (D8-S2), DLF stimulation still evoked rhythmic locomotor movements and EMG bursts in the left hindlimb that included HF-HE alternation and KE discharge. However, post-surgical movements and EMG bursts had longer cycle periods, and movements showed lower amplitudes compared to controls. These results show that (1) sufficient locomotor CPG circuitry resides within the turtle spinal hemi-enlargement to drive major components of the forward swim motor pattern, (2) contralateral circuitry contributes to the excitation of the locomotor CPG for a given limb, and (3) a sufficient portion of the descending DLF pathway crosses over to the contralateral cord anterior to the hindlimb enlargement to activate swimming.  相似文献   
75.
Widespread interest in global health issues is a common characteristic of students and faculty in schools of public health and schools of medicine. Building on strong university-based and community-based programs in global health, the University of Washington has created a unique Department of Global Health that is housed jointly in its School of Public Health and Community Medicine and its School of Medicine. The creation of this department has generated significant enthusiasm throughout the university and the Seattle community as a new paradigm for addressing global health education, research, and service. Placing the new Department of Global Health in two university schools and finding the appropriate niche for the department among the university's many global health initiatives presented challenges, as well as opportunities. This article describes the goals of the department, the process by which it was created, and what it expects to accomplish.  相似文献   
76.
ZC4H2 (MIM# 300897) is a nuclear factor involved in various cellular processes including proliferation and differentiation of neural stem cells, ventral spinal patterning and osteogenic and myogenic processes. Pathogenic variants in ZC4H2 have been associated with Wieacker-Wolff syndrome (MIM# 314580), an X-linked neurodevelopmental disorder characterized by arthrogryposis, development delay, hypotonia, feeding difficulties, poor growth, skeletal abnormalities, and dysmorphic features. Zebrafish zc4h2 null mutants recapitulated the human phenotype, showed complete loss of vsx2 expression in brain, and exhibited abnormal swimming and balance problems. Here we report 7 new patients (four males and three females) with ZC4H2-related disorder from six unrelated families. Four of the 6 ZC4H2 variants are novel: three missense variants, designated as c.142T>A (p.Tyr48Asn), c.558G>A (p.Met186Ile) and c.602C>T (p.Pro201Leu), and a nonsense variant, c.618C>A (p.Cys206*). Two variants were previously reported : a nonsense variant c.199C>T (p.Arg67*) and a splice site variant (c.225+5G>A). Five patients were on the severe spectrum of clinical findings, two of whom had early death. The male patient harboring the p.Met186Ile variant and the female patient that carries the p.Pro201Leu variant have a relatively mild phenotype. Of note, 4/7 patients had a tethered cord that required a surgical repair. We also demonstrate and discuss previously under-recognized phenotypic features including sleep apnea, arrhythmia, hypoglycemia, and unexpected early death. To study the effect of the missense variants, we performed microinjection of human ZC4H2 wild-type or variant mRNAs into zc4h2 null mutant zebrafish embryos. The p.Met186Ile mRNA variant was able to partially rescue vsx2 expression while p.Tyr48Asn and p.Pro201Leu mRNA variants were not. However, swimming and balance problems could not be rescued by any of these variants. These results suggest that the p.Met186Ile is a hypomorphic allele. Our work expands the genotypes and phenotypes associated with ZC4H2-related disorder and demonstrates that the zebrafish system is a reliable method to determine the pathogenicity of ZC4H2 variants.  相似文献   
77.
The renal and systemic changes after stenosis of the left renal artery (n = 5) or sham stenosis (n = 6) in conscious dogs were studied sequentially over 25 days. Stenosis produced a prompt rise in arterial pressure, which was at all times due to reduced peripheral vascular conductance, with no increase in cardiac output despite initial evidence of mild fluid retention. The decrease in peripheral conductance was attributable to 1) the stenotic kidney (25% of the total and due to the mechanical effect of the stenosis itself), 2) the nonstenotic kidney (about 15% of the total and not caused by angiotensin II), and 3) the nonrenal vasculature (60%). The decrease in conductance in the nonrenal vasculature was due partly to angiotensin II, but there was also a gradually developing non-angiotensin II component. Acute administration of captopril caused significantly greater changes in arterial pressure and peripheral conductance throughout the period of stenosis than before stenosis (and greater than in sham-stenosis dogs), indicating that angiotensin II was constricting the peripheral vasculature even when plasma renin levels were no longer elevated. In the stenotic kidneys, captopril produced a fall in renal vascular resistance, but renal blood flow did not rise because there was an approximately equal rise in the resistance of the stenosis. There was no evidence for a role for the autonomic nervous system in the hypertension, as ganglion blockade (pentolinium) had similar hemodynamic effects before and after stenosis. Thus, the hypertension was due at all times to reduced peripheral conductance, with the two kidneys responsible for 40% of this reduced conductance.  相似文献   
78.
OBJECTIVE: We undertook this study to determine whether additional use of selective venography, compared with nonselective venography alone, reveals more abnormal anatomic venous findings that lead to changes in vena cava filter (VCF) position. METHODS: From January 1998 to June 2002, 94 patients underwent VCF placement by vascular surgeons at a university tertiary care center. Indications, techniques, decision analysis, and complications were reviewed. Nonselective venography and selective venography of the inferior vena cava (IVC) were evaluated for image quality, abnormal findings, aberrant anatomy, and the anatomic relationship of vertebral bodies to major venous tributaries. RESULTS: Absolute and relative indications for VCF placement were 44% and 56%, respectively. Jugular, femoral, and subclavian vein approach was used in 47%, 47%, and 6% of patients, respectively. Seventy-three percent of VCFs were placed in the catheterization laboratory, 21% in the operating room, and 5% at the bedside. Nonselective venography was performed in 80 patients (85%), of whom 44% had undergone selective venography. At nonselective venography plus selective venography 7.5% of patients had an abnormal finding (IVC compression, n = 3; IVC thrombus, n = 2; tortuosity, n = 1). Similarly, 17.5% of patients had aberrant anatomy (accessory renal vein, n = 8; IVC duplication, n = 3; large low right gonadal vein, n = 2; megacava, n = 2). Nonselective venography plus selective venography demonstrated that 16% of VCFs required a major change in position, 10% of which were placed above the renal veins. Compared with nonselective venography alone, selective venography enabled detection of significantly more abnormal and aberrant findings (9% vs 49%; P <.001). Changes in VCF placement were necessary significantly more often in patients undergoing additional selective venography compared with nonselective venography alone (31% vs 4%; P =.003). In one patient in the series, a VCF was malpositioned in the iliac vein with intravascular ultrasound visualization. CONCLUSION: When nonselective venography plus selective venography were performed, 23% of patients had either an abnormal finding or aberrant anatomy, and most of these required a major change in VCF position. Nonselective venography plus selective venography redefines the criterion standard and, because of limitations of other methods of vena cava visualization for VCF deployment, should be performed in most patients.  相似文献   
79.
80.
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
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