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961.
The Accident Fear Questionnaire (AFQ) is a new self-rated scale for PTSD and “accident phobia” (subsyndromal PTSD) after road vehicle accident (RVA). AFQ data from 54 RVA survivors were compared with two clinician-rated and three self-report measures of psychopathology. Diagnoses were based on the DSM-III-R structured clinical interview for PTSD and on DSM-III-R criteria for specific phobia. Diagnostic groups were similar in regards to demographic variables, duration of illness, measures of pain, self-rated physical impairment, and duration of illness. The AFQ had good internal consistency with a Crohnbach's alpha of 0.89 and yielded the largest group differences between PTSD (n = 12), “accident phobia” (n = 14), and neither diagnosis (n = 28). Subjects with PTSD tended to score highest on all self-report measures of psychopathology, followed by “accident phobics”, followed by subjects with neither diagnosis. On the AFQ, this order of severity was preserved after subjects with major depression had been removed from the analysis. Lacking effects from depression and from pain suggest that the AFQ is a specific measure of RVA-related phobic avoidance.  相似文献   
962.
Previously we have shown that leukaemia inhibitory factor (LIF) potentiates the development of murine spinal cord neurons in vitro , suggesting that it, or related factors, may play an important regulatory role in neuronal development. We have further investigated this role and show here that the generation of neurons in cultures of embryonic day 10 spinal cord cells is inhibited by antibodies to the β subunit of the LIF receptor. Since there are more undifferentiated precursors in antibody-treated cultures than in control and LIF-treated cultures, it is concluded that the primary action of LIF, or related molecules, is to promote neuronal differentiation, not precursor survival. In addition, the failure of LIF to support neuronal survival in the period immediately following differentiation suggests that the increased numbers of neurons generated with LIF are not attributable to its neurotrophic action. By selecting neuronal precursors on the basis of their inability to express class I major histocompatibility complex molecules, it was shown that LIF acted directly upon these cells and not via an intermediary cell. LIF also appears to be involved in regulating the differentiation of astrocytes, since it increases the number of glial fibrillary protein (GFAP)-positive cells present in the cultures and since the spontaneous production of GFAP-positive cells is blocked by antibodies to the LIF β receptor. These findings suggest that LIF or related factors promote the differentiation of neural precursors in the spinal cord, but that they are not involved in preferentially promoting precursors down a specific differentiation pathway.  相似文献   
963.
A multicolour tandem labelling fluorescence in situ hybridization(FISH) procedure was used to compare the frequencies of radiation-inducedchromosome breakage and hyperdiploidy of chromosome 1 occurringin non-cultured granulocytes and Go lymphocytes with those observedin cultured metaphase and interphase lymphocytes. Whole blood,obtained from healthy male donors, was exposed in vitro to 0,100, 200, 300 and 400 cGy of ionizing radiation from a 137Cssource. Aliquots containing granulocytes and Go lymphocytesfrom each dose were treated immediately with hypotonic KCl onice and harvested. Cells were hybridized with  相似文献   
964.
The U.S. multiplant cohort mortality study of workers producing manufactured mineral fibers is finding increasing mortality from nephritis and/or nephrosis. We examine other data sets to see if similar effects can be identified. In a case-referent study among Michigan patients with end-stage renal disease (ESRD), men with exposures to silica have elevated odds ratio for ESRD. In a California occupational mortality study based on 1979–81 data, a number of the construction trades, farmers, and farm laborers show excess mortality for renal disease. The highest mortality ratio is found in the category including insulation workers. This ratio remains significantly elevated when adjusted for estimated exposures to smoking, alcohol, and for socio-economic status. California mortality data from 20 years earlier (1959–61) fail to show much excess renal disease in construction workers, but do for farmers. In Singapore, granite workers with a long-term exposure to silica have excess excretion of albumin and similar compounds compared to less exposed controls, leading to the presumption that silica exposure can lead to silica nephrotoxicity. Balkan nephropathy has been associated with consumption of well water high in silica. In the Negev of Israel, dust storms are a vehicle for increasing respiratory uptake of silica. The Beduin, thought to be a population with maximal exposures, have higher rates of ESRD than do Jews in the age groups over 60 years. Although high blood concentrations of silica are found in persons with renal failure, the close association with elevated creatinine has been interpreted as evidence that the buildup of silica is due to renal failure, rather than vice-versa. The evidence is consistent with, but not yet compelling, that exposure to silica, which can be readily absorbed (or dissolved) from the lung, may increase the long-term risk of renal disease including renal failure. © 1993 Wiley-Liss, Inc.  相似文献   
965.
The public sector in Britain has been subjected to over a decade of major reform aimed at breaking up public service monopolies, at containing costs while at the same time opening services up to greater consumer choice. Health and social services have not been exempt from this revolution in the organization and management of public sector services. The long-standing policy of care in the community is being subjected to market principles and the introduction of a ‘contract culture’ very similar to the NHS reforms introduced in 1991. This paper reviews the origins of these developments in the doctrines of ‘new public management’, a movement which has proved attractive to policy-makers in many countries. Local authority social services departments have been identified as the lead agency for the development of a mixed economy of care following a review of community care policy by the government's health adviser, Sir Roy Griffiths, and a subsequent white paper. This paper examines the limited empirical evidence available on how managers and providers are meeting the challenge bestowed upon them, and concludes that most authorities are moving ahead cautiously if at all. Only a handful of authorities studied have embraced the reforms with any degree of enthusiasm. The paper concludes with an assessment of the reforms from two perspectives: a pessimistic one and an optimistic one. There are many worrying features of the reforms, not least among these being a lack of clarity over their intended purpose. Tensions and contradictions are plentiful, which places in jeopardy the certainty of the reforms in becoming user led rather than provider driven. A more optimistic scenario is that the changes are leading to a loosening up of services and practices which have often suffered from sclerotic tendencies, paternalism and sometimes complacency. If the reform process is skilfully handled and not rushed and if the ends are clearly established and communicated then users and carers could prove to be the principal beneficiaries.  相似文献   
966.
A 45-year-old woman with history of iritis, uveitis, and sarcoidosis of the skin presented with a subacute cervical myelopathy. Magnetic resonance imaging (MRI) ;howed patchy, multifocal, gadoliniumenhancing intramedullary lesions of the spinal cord, and extramedullary lesions of the basal cisterns and fourth ventricle. Symptoms and MRI abnormalities were improved within 1 month of corticosteroid therapy.  相似文献   
967.
A method for rapidly producing velocity images is presented. This sequence combines a modified bipolar gradient pulse to magnitude encode the velocity with the rotating ultra-fast imaging sequence (RUFIS) to image the encoded spins. Velocity encoding is done in 3 msec, and RUFIS acquires 32 projections in 8 msec. The method is applied to turbulent jets associated with a 75% stenosis in a 15-mm inner diameter glass pipe. Data is acquired upstream and downstream from the stenosis for Reynolds numbers from 560 to 3750. In addition, a robust method of reconstructing the unobserved short time region of a free induction decay is presented and incorporated into the image processing.  相似文献   
968.
969.
By use of a double-labeling immunofluorescence method with a confocal laser scanning microscope, we have examined whether a calcium-binding protein, calretinin, is localized in magnocellular oxytocin and vasopressin neurons of the rat hypothalamus. In the supraoptic nucleus, all oxytocin-labeled cells were stained for calretinin. However, in the magnocellular part of the paraventricular nucleus, almost all oxytocin-stained cells were devoid of calretinin immunoreactivity. All vasopressin-positive cells of both the supraoptic nucleus and the magnocellular part of the paraventricular nucleus lacked calretinin immunoreactivity. No calretinin immunoreactivity was found in oxytocin-labeled cells of the the anterior commissural nucleus or in vasopressin-labeled cells of the suprachiasmatic nucleus. We previously showed that another calcium-binding protein, calbindin-D28k, was localized in magnocellular oxytocin neurons of the supraoptic nucleus but not in those of the paraventricular nucleus. These findings suggest that, in general, magnocellular oxytocin neurons of the supraoptic nucleus and those of the paraventricular nucleus can be chemically distinguished, that is, the former contain both calretinin and calbindin-D28k but the latter lack the two calcium-binding proteins.  相似文献   
970.
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