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21.
David  Friedman  Lois  Putnam  Walter  Ritter  Marla  Hamberger  Steven  Herman 《Psychophysiology》1992,29(5):593-609
Event-related potentials were recorded in a developmental study of picture matching using an adaptation of Posner's (1978) letter-matching tasks. Subjects ranging in age from 6-39 were asked to decide whether two line drawings, presented sequentially, were the same or different on the basis of physical (physical identity), nominal (name identity), or categorical (category identity) criteria. The amplitude of a negativity at 400 ms (Neg400) increased as the number of dimensions on which the two line drawings differed increased. This effect held for all age groups, and was interpreted as reflecting the degree of semantic and/or physical relationship between the two pictures. However, one finding for Neg400 did suggest a qualitative difference in processing mode between the younger and older subjects. Both Neg400 and P3b latencies showed highly significant linear age trends, decreasing with increasing age. These age-related changes were interpreted as demonstrating quantitative speed of processing differences among age groups. The latencies of both Neg400 and P3b increased as the matching criteria became more complex. Moreover, P3b latency increased as the number of dimensions on which the two pictures differed increased, and this did not interact with age. Although both Neg400 and P3b showed age-related changes in scalp distribution, the fact that each was related to the experimental variables in similar fashion in all age groups suggested that they were homologous components across the age range studied. Taken as a whole, the data support continuity of information processing during these tasks across a wide age range.  相似文献   
22.
This paper characterizes a novel gene, previously identified as uniquely regulated at implantation in mouse uterus. We cloned its full mRNA sequence encoding a serine protease possessing an IGF-binding domain and named it pregnancy-related serine protease (PRSP). PRSP is structurally similar to mammalian HtrA1 (56% amino acid similarity). Northern analysis revealed that the expression of PRSP mRNA was low before pregnancy, but it was increased at implantation and markedly up-regulated post-implantation. In-situ hybridization localized low levels of mRNA expression to the epithelium and stroma during very early pregnancy, but high expression to the decidual cells on day 8.5, primarily at the mesometrial pole where the placenta was forming. By day 10.5, PRSP mRNA was detected in the placenta. We also cloned an alternatively spliced PRSP mRNA that is expressed at a very low level. We located PRSP gene on chromosome 5 and established its intron/exon structure, which unambiguously explains how the two mRNA variants are produced through alternative splicing. Based on PRSP protein domain structure and its unique expression during pregnancy, we propose that PRSP plays an important role in the formation/function of the placenta.  相似文献   
23.
The ability to excrete a volume of isotonic saline equal to 10% of body weight infused over 60 min, was examined in awake rats and in rats anesthetized with 1 of the 2 agents most commonly used in renal clearance studies, Inactin or Nembutal. Rats anesthetized with Inactin excreted significantly less of the infused sodium during the period of infusion and in the 120-min post-infusion periods as compared to Nembutal-anesthetized rats or awake rats. Following saline infusion, there was a significantly greater decrease in serum protein concentration (25.5±4.7%) in rats anesthetized with Inactin, compared to that observed in the awake or Nembutal-treated rats. In a separate group of saline-infused awake rats, induction of anesthesia with Inactin resulted in a significant increase in hematocrit and a decrease in serum protein concentration. These studies suggest that Inactin anesthesia decreases the ability of the kidney to excrete a saline load and that, in studies of sodium excretion in the rat, especially if volume expansion is to be part of the experimental protocol, Nembutal rather than Inactin may be the anesthetic of choice.These studies were performed while Drs. Knight and Frankfurt were Fellows in Nephrology of Baylor College of Medicine, and were supported in part by a Clinical Investigatorship award to Dr. Weinman and an Associate Investigatorship award to Dr. Frankfurt from the Veterans Administration. This work was presented in part at the Combined Session, Southern Section, American Federation for Clinical Research and the Southern Society for Clinical Investigation, New Orleans, Louisiana, January 27–29, 1977, and has appeared in abstract form in Clin. Res.25, 61 A (1977)  相似文献   
24.
The intensity of acoustic stimulation is frequently a variable of interest in psychophysiological studies but calibration procedures, particularly when earphones are employed, are not always adequate. The present study demonstrates that intensity is underestimated, more seriously at low frequencies, when calibration does not employ an appropriate coupler. Several standardized calibration methods are discussed in terms of their suitability For routine laboratory use.  相似文献   
25.
Objectives

The purpose of this study was to examine differences between perceived harm of cigarette and electronic cigarette (e-cigarette) use while pregnant and differences between healthcare providers’ communication about these products during pregnancy.

Methods

A convenience sample of gestational women (n?=?218; ages 18–45) living in the US completed an online survey between May and December 2017. Participants reported perceived likelihood of adverse health outcomes (e.g., low birth weight, sudden infant death syndrome) among infants/children born to mothers who used cigarettes/e-cigarettes. T-tests and two-way ANOVAs examined differences between risk perceptions of using cigarettes/e-cigarettes while pregnant based on pregnancy status (previously pregnant, currently pregnant, future pregnant). Chi-square analyses examined differences between healthcare provider communication about cigarette/e-cigarette use during pregnancy.

Results

Overall, participants believed adverse health outcomes were significantly more likely to be caused by maternal use of cigarettes than e-cigarettes. Participants who planned to be pregnant reported higher endorsement that smoking combustible cigarettes would cause a miscarriage (p?<?.05) or increased blood pressure (p?<?.05) for a child than currently pregnant participants. Participants reported healthcare providers asked about (p?<?.05), advised them not to use (p?<?.001), and talked to them about health effects of smoking combustible cigarettes while pregnant (p?<?.001) significantly more than e-cigarettes.

Conclusions for Practice

Healthcare providers working with pregnant women should perform the 5As behavioral intervention method to provide pregnant women with tobacco cessation care. They should also discuss the absolute harm nicotine exposure (via cigarettes or e-cigarettes) can have on fetal health and development.

  相似文献   
26.
PurposeWe present a conceptual framework based on a review of the literature to highlight the interconnecting and reinforcing elements of a violence syndemic and how this syndemic influences sexual risk behaviors among African American heterosexual adolescents.MethodsWe review existing peer-reviewed published research from 2000 to 2020 that links a violence syndemic (i.e., racism and race-related stress, neighborhood and police violence, peer violence, and family violence and disruptions) to adolescent sexual risk behaviors. Empirical findings and theoretical underpinnings are used to document this relationship and illuminate the factors that mediate this relationship.ResultsEmpirical studies support the links between specific types of violence and sexual risk behaviors among African American adolescents. Further, existing studies point to the important relationships among the specific types of violence, supporting a violence syndemic approach.ConclusionsWhile more researchers are examining socio-ecological contextual factors as important predictors for sexual risk behaviors, there remains inadequate understanding about how violence types reinforce one another to heighten sexual risk behaviors among African American heterosexual adolescents. This article presents new directions for adolescent research, especially how a violence syndemic approach can be used to explain sexual risk, but also to refocus intervention design on the complex burdens experienced by this population.  相似文献   
27.
28.
Several indices have been introduced as convenient alternatives to calculation of the physiological shunt fraction (Qs/QT) for the assessment of pulmonary gas exchange. These include: the arterial-alveolar oxygen tension ratio (a/APO2), the arterial oxygen tension-inspired oxygen concentration ratio (PaO2/FIO2), the respiratory index (RI), [A-a)DO2/PaO2) and the alveolar-arterial oxygen tension difference [A-a)Do2). These indices are in use clinically despite the fact that they may not accurately predict gas exchange in situations where FIO2, Qs/QT or arterial-venous oxygen content is changing. The clinical stability of each of these indices, relative to the behaviour of the physiological shunt, was therefore investigated prospectively in ten mechanically ventilated postoperative adults as FIO2 was varied from 0.30 to 1.00. None of the indices studied reliably reflected the behaviour of the physiological shunt. As FIO2 was increased incrementally from 0.30 to 1.00, 42 to 55 per cent of the measured changes in these indices were opposite in direction to the corresponding changes in the physiological shunt. The maximum magnitudes of the opposite changes were substantial; 24 and 22 per cent for the a/APO2 and PaO2/FIO2 ratio respectively, 67 per cent for the RI and 101 per cent for the (A-a)DO2. We conclude that the use of any of these indices for clinical assessment of a patient's gas exchange defect when FIO2 is varying can be substantially misleading.  相似文献   
29.
An endoaortic calcified mass, sometimes referred to as a coral reef aorta, is an unusual cause of distal leg microembolization. When discovered it is usually in the suprarenal aorta. We present an unusual case of infrarenal coral reef aorta with symptoms of distal atheroembolism. A review of the literature is also presented.  相似文献   
30.
Summary The paper focuses on the relationship between changing societal norms toward women's roles and actual, emotional acceptance of them for oneself, specifically as the norms relate to abortion and sexual behavior. Elective abortion still is regarded by many as a deviant activity. Such a view has sprung from an uncritical acceptance of the traditional role of women. The implications are that women who have abortions accept traditional norms for sexual behavior, in spite of their own sexual activity, and have a generally traditional view of women's roles. They are considered to behave stereotypically and to have failed. Traditional norms for women's roles have been challenged in recent years, however, especially by the feminist movement. The authors hypothesized that women who sought early abortions would tend to have feminist orientations. The paper is based on a study of 1598 women with problem pregnancies, part of a larger study conducted throughout Michigan during 1974–75. The women studied showed little lag in emotional acceptance of changing norms about women's roles. They indicated a non-traditional female role orientation, and seemed to see themselves as competent, selfdirected, and legitimately sexual persons. Most did not have any great conflict over the decision to have an abortion. The findings by and large substantiated the authors' hypotheses.This research is supported by Grant Number 1 RO 1 HD0773901, National Institute of Child Health and Human Development, Washington, D. C.  相似文献   
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