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61.
62.
David Shitrit Lev Nirit Sheely I Shiran Gabriel Izbicki Dov Sofer Melamed Eldad Mordechai R Kramer 《The Journal of heart and lung transplantation》2003,22(8):946-950
Progressive multifocal leukoencephalopathy (PML) is a sub-acute, demyelinating disease of the brain caused by a human polyomavirus. We describe a patient with the onset of PML 7 months after lung transplantation. The patient was treated with immunosuppressive modulation and cidofovir, a new anti-viral therapy for PML, with stabilization of the symptoms. We also review the 4 additional reports in the literature of PML after heart and lung transplantation. Progressive multifocal leukoencephalopathy may become more prevalent as the population of heart and lung transplantation recipients increases. 相似文献
63.
The effects of GABA receptor agonists on prolactin secretion in vitro was examined using a rapid superfusion system. GABA and muscimol caused a biphasic effect on prolactin secretion, both components of which were antagonised by bicuculline methiodide, while baclofen had no effect on basal or stimulated secretion, demonstrating the GABAA receptor specificity of both components. Homocarnosine caused only inhibition of secretion, and a range of partly rigid GABA analogues were relatively poor at causing stimulation of secretion. Both effects of muscimol were antagonised by low-chloride medium and the anion channel blocker DIDS, but strychnine and picrotoxinin were both potent and selective antagonists of the stimulatory effect. These results demonstrate a novel biphasic effect of GABAA agonists or prolactin secretion, the two components of which appear to be independent and mediated by different types or states of GABAA receptor/chloride channel complex. 相似文献
64.
Elevated adenosine deaminase activity and hereditary hemolytic anemia. Evidence for abnormal translational control of protein synthesis. 总被引:1,自引:0,他引:1 下载免费PDF全文
E G Chottiner H J Cloft A P Tartaglia B S Mitchell 《The Journal of clinical investigation》1987,79(3):1001-1005
We have investigated the molecular basis of the marked elevation in erythrocyte adenosine deaminase (ADA) activity in a kindred with hereditary hemolytic anemia. Red cell ADA-specific activity was verified to be 70- to 100-fold normal levels. Western blots demonstrated a corresponding increase in erythrocyte ADA-specific immunoreactive protein. Analysis of genomic DNA revealed no evidence for amplification or major structural changes in the ADA gene. ADA-specific messenger RNA (mRNA) from proband reticulocytes was comparable in size and amount to mRNA from control reticulocytes. Translation of proband poly A+ reticulocyte mRNA in a rabbit reticulocyte lysate system and immunoprecipitation of 35S-labeled protein products with anti-ADA antibody yielded a band of approximately 42,000 apparent mol wt that was absent in translation products from control reticulocyte mRNAs. These data suggest that the increased ADA activity in red cells in this disorder results from the increased translation of an aberrant ADA mRNA. 相似文献
65.
S D Harlow S Crawford L Dennerstein H G Burger E S Mitchell M-F Sowers 《Climacteric》2007,10(2):112-119
In 2001, the Stages of Reproductive Aging Workshop (STRAW) proposed bleeding and endocrine criteria for defining the early and late menopausal transition stages. Based on expert consensus, STRAW recommended a shorter interval of amenorrhea than the commonly used 90-day amenorrhea criteria for late transition and a >7-day change in cycle length for early transition. The ReSTAGE collaboration used prospective menstrual calendar data from four cohorts (TREMIN, Melbourne Women's Midlife Health Project, Seattle Midlife Women's Health Study, and Study of Women's Health Across the Nation) to quantitatively evaluate STRAW's recommendations. This empirical assessment supported the STRAW recommendations that (1) > or =60 days of amenorrhea be used to define the late menopausal transition and (2) that early transition is consistent with a persistent 7 or more day difference in length of consecutive cycles. Serum follicle stimulating hormone (FSH) values > or =40 IU/l was an independent marker of the transition and, when occurring together with a bleeding marker, increased prediction of final menstrual period. Such a FSH criterion could be incorporated into the STRAW paradigm to facilitate prediction of proximity of the final menstrual period. 相似文献
66.
From a population of singleton pregnancies, 152 overweight women (greater than 110% of standard) were matched with normal weight women (95-110%) for age, height, parity, race, and smoking habits. Comparisons were made of initial weight (weight at the first prenatal visit) and gestational weight gain and pregnancy outcome. Mean birth weights and gestational ages of infants of normal and overweight women were not significantly different. For normal weight women birth weight increased significantly as height, initial weight, and body mas index increased (p less than 0.01), but no such relationship existed for overweight women. The lack of effect of initial weight on birth weight in overweight women is attributable, in part, to the significantly less gestational weight gains of these mothers (6.3 kg vs 8.2 kg). When normal and overweight gravida had gestational weight gains of less than 7 kg, offspring of overweight mothers were significantly heavier. Gestational weight gain was positively correlated with birth weight for both normal (p less than 0.0001) and overweight women (p less than 0.001). Within the overweight and normal weight groups, smokers had lower initial weights and gestational weight gains than nonsmokers. Offspring of normal weight smokers had a mean birth weight 232 g less than that of nonsmokers (p less than 0.01). The difference in birth weight between overweight smokers and nonsmokers (135 g) was not statistically significant. While there is substantial data to support a weight gain of 10-12 kg in normal weight gravida, it would appear that a gain of approximately 7 kg in overweight middle class women does not impair fetal growth as measured by birth weight.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
67.
To investigate indirectly the central neurotransmitter mechanisms of D,L-fenfluramine-induced hormone release, prolactin, adrenocorticotropic hormone, cortisol, growth hormone, 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5HIAA) responses to D,L-fenfluramine (60 mg, oral) were examined in a single-blind, placebo-controlled trial in 14 normal subjects. As compared with placebo, D,L-fenfluramine significantly increased both prolactin and cortisol. There was a significant correlation between the cortisol and prolactin responses. HVA levels were also significantly increased, but there were no changes in MHPG or 5HIAA. The elevation in HVA significantly correlated with increases in both prolactin and cortisol. These findings are consistent with recent animal studies suggesting that D,L-fenfluramine-induced prolactin and cortisol release may be mediated, at least in part, by catecholaminergic systems. 相似文献
68.
J A Sorenson C R Mitchell J D Armstrong H Mann D G Bragg F A Mann I B Tocino M M Wojtowycz 《Investigative radiology》1987,22(10):772-780
We evaluated the effects of unsharp masking and highly efficient scatter rejection on film-screen chest radiographs of cancer patients. Unsharp masking significantly improved the detectability of lung nodules and visibility of anatomic structures in poorly penetrated areas of the chest. Highly efficient scatter rejection by an improved antiscatter grid provided only modest additional benefits. The study supports the conclusion that nodule detection in poorly penetrated areas on conventional chest radiographs is limited primarily by display contrast, whereas in the well-penetrated lung fields it is limited primarily by confusing background structures, rather than inadequate contrast. A method for analyzing clinical nodule detection data by transforming the FROC data to ROC coordinates also is demonstrated. 相似文献
69.
70.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献