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51.
Age of onset reports obtained retrospectively for each symptom of DSM-III-R alcohol dependence (AD) are used to study patterns of lifetime symptom progression in a large general-population survey of people in the United States. It is shown that symptom progression among a substantial majority of respondents can be summarized as movement across three clusters. Cluster A is defined by symptoms of role impairment/hazardous use (A4), use despite social, psychological or physical problems (A6), and drinking larger amounts or over a longer period of time than intended (A1). Cluster B is defined by tolerance (A7) and impaired control (A2, A3). Cluster C is defined by withdrawal (A8, A9) and giving up activities in order to drink (A5). Clusters are shown to follow a time sequence, with at least one symptom in Cluster A usually occurring first, followed by symptoms in Clusters B and C. In all, 83.4% of the symptom cluster transitions estimated from retrospective age of onset reports are consistent with this progression. Progression to AD is differentially predicted by symptom profiles reported at the age of first symptom onset, with persons reporting Cluster C symptoms most likely to progress subsequently to AD. Furthermore, profiles of AD defined by the highest symptom cluster present at AD onset are differentially predicted by prior personal and parental histories of psychopathology and, among men, are predictive of diagnosis persistence. 相似文献
52.
JE Eberhart-Phillips PD Frederick RC Baron L Mascola 《Canadian Metallurgical Quarterly》1993,82(5):797-801
OBJECTIVE: To describe the effects of measles in pregnancy using a large case series. METHODS: Pregnant women with measles were identified by county health department records, and their hospital and clinic records were reviewed. When available, records for the infants of case patients were also reviewed. RESULTS: Fifty-eight pregnant women with measles were identified. Thirty-five (60%) were hospitalized for measles, 15 (26%) were diagnosed with pneumonia, and two (3%) died of measles complications. Excluding three induced abortions, 18 pregnancies (31%) ended prematurely; five were spontaneous abortions and 13 were preterm deliveries. All but two of the 18 pregnancies that terminated early did so within 14 days of rash onset. Two term infants were born with minor congenital anomalies, but their mothers had measles late in the third trimester. No newborns were diagnosed with congenital measles. CONCLUSIONS: The incidence of death and other complications from measles during pregnancy may be higher than expected for age-comparable, nonpregnant women. Measles in pregnancy may lead to high rates of fetal loss and prematurity, especially in the first 2 weeks after the onset of rash. 相似文献
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BACKGROUND: FRTL-5 thyroid cells are a cell line extensively used for the investigation of thyroid functions. Activation of alpha-1 adrenergic receptors stimulates both arachidonic acid (AA) release and cytosolic Ca2+ increase in this cell line. Cytosolic Ca2+ and arachidonic acid are known to be important second messengers regulating a variety of thyroid functions. The generation of these messengers is regulated primarily by two different types of phospholipases, phospholipase C (PLC) and phospholipase A2 (PLA2). METHODS: Norepinephrine (NE, 10 mumol/L) was used as an alpha-1 adrenergic activator, and cytosolic-free Ca2+ concentration ([Ca2+]i) was determined using the fluorescent dye indo-1. Arachidonic acid release was measured as an indicator of PLA2 activation, and protein kinase C (PKC) activity determination and isoforms identification were performed using commercial kits. RESULTS: Norepinephrine increased [Ca2+]i and AA release. Prevention of NE-induced cytosolic Ca2+ influx, either by removal of extracellular Ca2+ or by use of Ca2+ channel blockers, NiCl2 or CoCl2, inhibited AA generation entirely. Inhibition of NE-induced increase in [Ca2+]i by the Ca2+ chelator, 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA), also significantly suppressed NE-induced AA release. Inhibition of PKC activity by PKC inhibitors (H-7 or staurosporine) or downregulation induced by prolonged treatment with phorbol 12-myristate 13-acetate (PMA) or thyleametoxin (TX) significantly blocked the NE-induced AA release, which indicates PKC is involved in mediating NE-induced AA release. Protein kinase C activity measurement indicated that NE induced an activation of PKC in 5 minutes. To further characterize the role of PKC or Ca2+ in regulation of AA release, we identified PKC isoforms by immunoblotting with specific antibodies against 8 different Protein kinase C isoforms. PKC-alpha, -beta I, -beta II, -gamma, delta, -epsilon, -zeta, and -eta isoforms were identified. Norepinephrine induced translocation of PKC-alpha, -beta I, -beta II, -gamma, -delta, and -epsilon isoforms but not -zeta and -eta from cytosol to membrane. Chelation of intracellular Ca2+, prevention of Ca2+ influx, or prolonged treatment with thymeleatoxin (TX) completely blocked the NE-induced translocation of PKC-alpha. CONCLUSIONS: These results, taken together with data obtained from AA experiments, suggest that PKC plays a critical role in alpha-1 adrenergic receptor mediated PLA2 activation and subsequent AA release. Extracellular Ca2+ influx is a prerequisite for both PKC-alpha translocation and AA release. Whether Ca2+ acts directly upon the PLA2, or via PKC-alpha, to regulate AA generation is an intriguing question that remains to be clarified. 相似文献
55.
LM Brown 《Canadian Metallurgical Quarterly》1993,154(1-2):43-46
Developmental alterations in N-methyl-D-aspartate (NMDA)-stimulated[3H]norepinephrine release from rat brain cortical and hippocampal slices were studied. NMDA (10-1000 microM) resulted in a concentration-dependent increase in [3H]norepinephrine efflux; maximal responses (% released) in the cortex were: (1.53 +/- 0.12, 3.68 +/- 0.20, 2.94 +/- 0.20, 4.60 +/- 0.28 and 5.28 +/- 0.33) and the hippocampal responses were: (1.90 +/- 0.18, 3.84 +/- 0.23, 3.60 +/- 0.28, 5.16 +/- 0.38 and 5.81 +/- 0.45) at varying postnatal ages (1, 7, 14, 21 and 90 days) respectively. Cortical tissue from 7-day-old pups exhibited a transient increase in maximal efflux and a decrease in EC50. These results indicated that developmental alterations in the NMDA receptor appear to be translated into differences in NMDA stimulated [3H]norepinephrine release. 相似文献
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58.
B Cullen D Silcock LJ Brown A Gosiewska JC Geesin 《Canadian Metallurgical Quarterly》1997,29(1):241-250
Until recently, research on the pathogenesis of glomerulonephritis has been mainly focused on the characterization of humoral immune responses in the initiation of glomerular injury. However, there is a growing recognition that both cellular and humoral immune responses, in varying proportions, are involved in the pathogenesis of immunologically-mediated glomerulonephritis. T lymphocytes are essential cellular elements of cell-mediated immunity. Both in experimental models of immune-mediated renal disease and in histopathological analyses of human nephropathies, the involvement of T cells has been demonstrated in the immunoregulation of nephritogenic immune responses and in the immune injury in the kidney. T cell activation resulting in either delayed-type hypersensitivity, cytolytic reactions, abnormal expression of major histocompatibility complex (MHC) molecules, or B cell activation can result in glomerulonephritis. These different types of responses are exerted by distinct T cell subsets defined by cell surface markers and cytokine profiles. CD4+ T cells in vivo are functionally heterogeneous with respect to cytokine production and the CD45 isoforms that are found on their surface. Like CD4+ T cells, CD8+ T cells may also be heterogeneous at the level of cytokine production. The roles of CD4+ and CD8+ cells and their cytokine profiles in glomerulonephritis have not been extensively investigated yet, but such studies might improve the understanding of the pathogenesis and possibly lead to new therapeutic approaches of human glomerulonephritis. In this review the role of distinct T lymphocyte subsets in experimental and human glomerulonephritis will be discussed. 相似文献
59.
Rothenberg B.C. Brown J.E.C. Hurst P.J. Lewis S.H. 《Solid-State Circuits, IEEE Journal of》1997,32(5):713-721
A mixed-signal RAM decision-feedback equalizer (DFE) that operates at 90 Mb/s is described. In the analog domain, the DFE subtracts intersymbol interference caused by the past four outputs. The equalized signal is fed into a nonuniform flash analog-to-digital converter (ADC) to produce the decision output and error signal used to adapt the RAM contents in the digital domain. With a 5 V supply voltage, the power dissipation is 260 mW during steady-state operation. The active area is 4.5 mm2 in a 1 μm CMOS process 相似文献
60.