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21.
Most theories of grieving derive from Sigmund Freud and Erich Lindemann's understanding of mourning and include two assumptions: (a) Grieving is time limited; the process should be completed or resolved after a year or two; and (b) The main task of grieving is to achieve “decathexis.” One should detach oneself from emotional ties to the deceased so as to be able to form new relationships. This study presents evidence that these assumptions are flawed and that modern theories of grieving fall short of explaining the complicated reality of the mourning process. An alternative model is presented arguing that when a “high-grief” death occurs, a griever may be able to adapt and adjust to loss, but the grieving continues indefinitely. Implications of this model for older grievers are explored.  相似文献   
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The National Cancer Institute (NCI) is the largest single sponsor of studies using anti-neoplastic agents with over 100 compounds currently in various stages of clinical testing. Most of the clinical trials are conducted by the NCI sponsored cooperative oncology groups and community oncology programs, cancer centers, and the pharmaceutical industry. These organizations conduct studies both independently as well as in a collaborative fashion.  相似文献   
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During much of the past century, the microbe itself stood at the heart of microbial pathogenesis. Little thought was devoted to the host per se, though it was granted that differences in susceptibility to certain infections did exist between individuals, and between different ethnic groups. During the past 20 years, extraordinary strides in our grasp of mammalian genetics have made the host side of the equation far more approachable. A restricted collection of genes now presents itself as the likely repository for genetic differences that foretell susceptibility to infectious disease. The Toll-like receptors, of which 10 are presently known to exist in humans, offer an excellent example of this genetic reductionism, in that they embody the afferent component of the innate immune system, and strongly influence the containment of an infection from its earliest stages. The Toll-like receptors were identified as the culmination of a long and relentless inquiry into the yet-unsolved clinical problem of sepsis.  相似文献   
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Single parent women   总被引:1,自引:1,他引:0  
Summary While there has been considerable interest in the problems of single parent families, no study has yet determined if the problems are due to increased risk of specific psychiatric disorders in single parents as compared to their married counterparts. Data collected as part of the National Institute of Mental Health Epidemiologic Catchment Area (ECA) Project are presented to compare the psychiatric as well as economic and social functioning of single vs. married parent women ages 18–44, based on a probability sample of members of the greater New Haven community. The major finding between groups is their relative similarity in psychiatric as well as social functioning. The major difference is economic. Single parents, both Black and White, more frequently are less educated and poorer. While many are on welfare, single compared to married female parents are more likely to be working and to report insufficient income to meet their needs. There are no appreciable differences in social contacts, use of health services or six-month prevalence rates of psychiatric disorders including major depression, alcohol or drug abuse. The data suggest that the problems faced by single parent women and their children may be a reflection of poverty and stress in families and not of psychiatric disorders or poor social relations in mothers.  相似文献   
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Background: Although the activation-induced intracellular Ca2+ signal is disrupted by sensory neuron injury, the contribution of specific Ca2+ channel subtypes is unknown.

Methods: Transients in dissociated rat dorsal root ganglion neurons were recorded using fura-2 microfluorometry. Neurons from control rats and from neuropathic animals after spinal nerve ligation were activated either by elevated bath K+ or by field stimulation. Transients were compared before and after application of selective blockers of voltage-activated Ca2+ channel subtypes.

Results: Transient amplitude and area were decreased by blockade of the L-type channel, particularly during sustained K+ stimulation. Significant contributions to the Ca2+ transient are attributable to the N-, P/Q-, and R-type channels, especially in small neurons. Results for T-type blockade varied widely between cells. After injury, transients lost sensitivity to N-type and R-type blockers in axotomized small neurons, whereas adjacent small neurons showed decreased responses to blockers of R-type channels. Axotomized large neurons were less sensitive to blockade of N- and P/Q-type channels. After injury, neurons adjacent to axotomy show decreased sensitivity of K+-induced transients to L-type blockade but increased sensitivity during field stimulation.  相似文献   

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