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82.
Sex hormones and anabolic-androgenic steroids are implicated in the development and progression of hepatic adenomas (HA). We studied the expression of their receptors in HA and adjacent liver. Archival tissue sections of 27 HA (16 resections, four needle biopsies, seven aspirations) from 18 patients, and the adjacent liver, were immunostained with monoclonal antibody to estrogen receptor (ER, 1/80) (Dako, Carpinteria, CA), progesterone receptor (PR, 1/50) (BioGenex, San Ramon, CA), and androgen receptor (AR, 1/80) (BioGenex). An avidin-biotin complex technique was used with microwave antigen retrieval. Nuclear expression was assessed as 1+ to 3+ intensity, with semiquantitation of the percentage of nuclei immunopositive. Five percent or more nuclei immunopositive was regarded as positive. The 18 patients included 16 females of 34 years mean age (range, 16 to 49) with an available history of oral contraceptives in five; the two men were 24 and 30 years, with no history of androgenic steroids. ER, PR, and AR were present in seven (26%) (1+/-2+ intensity, 5% to 10% of nuclei) of HA, seven (26%) (1+/-2+ intensity, 5% to 30% of nuclei) and nine (33%) (1+/-3+ intensity, 5% to 80% of nuclei), respectively. In the adjacent liver in 11 cases, there were one (9%) ER, (2+ intensity, 5% of nuclei), four (36%) PR (1+/-2+ intensity, 5% to 20% of nuclei), and two (18%) AR (2+/-3+ intensity, 10% of nuclei). Receptors are present and may mediate the action of sex hormones or androgenic steroids on HA and adjacent liver, but in less than one third of patients. This may have therapeutic implications. 相似文献
83.
Dobutamine-induced hypotension has been disregarded as a marker of more severe functional abnormalities in patients with suspected coronary artery disease. However, its functional significance in patients with myocardial infarction has not been studied. The aim of this study was to define the predictors of systolic blood pressure (SBP) response to dobutamine in patients with previous myocardial infarction. Dobutamine stress (up to 40 microg/kg per minute) echocardiography was performed in 326 patients with prior myocardial infarction referred for evaluation of myocardial ischemia. A 16-segment, four-grade score model was used to assess left ventricular function. Wall motion score index was derived by summation of wall motion score divided by 16. SBP and heart rate increased from rest to peak dobutamine stress (127 +/- 22 vs 134 +/- 27 mm Hg and 72 +/- 14 vs 122 +/- 24 bpm, p < 0.00001 in both). An increase of SBP > or = 30 mm Hg occurred in 50 patients (15%). By multivariate analysis, independent predictors of failure of SBP increase were higher peak wall motion score index (p < 0.001), higher resting SBP (p < 0.01), and medication with calcium channel blockers (p < 0.05). SBP drop > or = 20 mm Hg occurred in 54 patients (17%). Independent predictors of SBP drop were higher resting wall motion score index (p < 0.001), higher resting SBP (p < 0.0001), and older age (p < 0.05). In patients with myocardial infarction, left ventricular function and baseline systolic blood pressure are powerful predictors of SBP response to dobutamine stress testing. 相似文献
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PB Sullivan 《Canadian Metallurgical Quarterly》1995,9(3):519-528
Helicobacter pylori is the major cause of antral gastritis in children, however, it is not always associated with symptoms. The exception to this occurs in duodenal ulcer disease with which H. pylori is linked in children albeit less strongly than in adults. Duodenal ulcers do not recur in older children following eradication of H. pylori. The importance of asymptomatic carriage of H. pylori in children, particularly in relation to the duration of this infection and the subsequent development of gastric cancer, remain to be established. Helicobacter pylori is associated with both hypochlorhydria and persistent diarrhoea in children in developing countries, but the significance of this association is still unknown. Although there is no consensus on the optimal regimen for treating H. pylori infection in children, dual therapy with amoxycillin and bismuth subcitrate for 2 weeks followed by monotherapy with bismuth subcitrate for a further 6 weeks will eradicate H. pylori infection in the majority of children. Those who relapse may be treated with a repeat course plus metronidazole for 4 weeks. Compliance with such regimens is a problem and shorter treatment courses that are equally effective in children need to be defined. Similarly, studies are required on the influence of the intrafamilial reservoir of H. pylori infection on relapse after treatment and the need for whole family eradication therapy. 相似文献
87.
RATIONALE AND OBJECTIVES: The authors compared complications and hemodynamic and electrophysiologic effects of two formulations of diatrizoate, one with additives that bind calcium and one without, in diagnostic cardiac angiography. METHODS: Two hundred twenty-three consecutive low-risk patients alternately received Hypaque 76 (group 1, little calcium binding effect), and MD 76 (group 2, significant calcium binding). Electrocardiographic and hemodynamic changes related to coronary angiography and left ventriculography were measured, and complications requiring treatment were recorded. RESULTS: There were more complications in patients in group 2 than in group 1 (18 versus 8, P = 0.04). Arterial pressure fell more, the QT interval increased more, and the heart rate fell more in group 2 after coronary angiography. CONCLUSIONS: Formulations of diatrizoate that minimize calcium binding are advocated for cardiac angiography when using high osmolality contrast media. The more detrimental effects that calcium binding has on myocardial function and cardiac conduction may lead to the higher incidence of complications. 相似文献
88.
JL Martal NM Chêne LP Huynh RM L'Haridon PB Reinaud MW Guillomot MA Charlier SY Charpigny 《Canadian Metallurgical Quarterly》1998,80(8-9):755-777
IFN-tau (IFN-tau) constitutes a new class of type I IFN which is not virus-inducible, unlike IFN-alpha and IFN-beta, but is constitutively produced by the trophectoderm of the ruminant conceptus during a very short period in early pregnancy. It plays a pivotal role in the mechanisms of maternal recognition of pregnancy in ruminants and it displays high antiviral and antiproliferative activities across species with a prominent lack of cytotoxicity at high concentrations in vitro in cell culture and possibly in vivo. It exhibits high antiretroviral activity against HIV and exhibits immunosuppressive activity in a multiple sclerosis model and reduces embryo and fetal mortality by stimulation of IL-10 production. In this review all the biochemical and para-hormonal properties of this novel IFN-tau are described in detail: structural characteristics of proteins and genes, trophoblast expression, regulation of its expression, structure of its gene promoter, its absence in human species and in non-ruminant animals, the evolution of the IFN-tau genes, its structure-function relationships with its three-dimensional structure, structural localization of biological activities, its lack of cytotoxicity and its receptor. Surprisingly, for an IFN, IFN-tau is also a pregnancy-embryonic signal with paracrine antiluteolytic activity. In order to maintain luteal progesterone secretion, IFN-tau inhibits PGF-2alpha pulsatile secretion and oxytocin uterine receptivity in early pregnancy. It is believed to suppress pulsatile release of endometrial PGF-2alpha by preventing oxytocin and estrogen receptor expression. Additionally, it directly regulates prostaglandin metabolism and possibly the PGE:PGF-2alpha ratio. 相似文献
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PB Hoebeke E Van Laecke A Raes J Vande Walle W Oosterlinck 《Canadian Metallurgical Quarterly》1997,32(4):480-484
OBJECTIVE: Based on 4 cases of infravesical obstruction due to extreme caliber disproportion between the posterior urethra and the penile urethra, a pathophysiological mechanism for this dynamic obstruction is given and endoscopic treatment is described. SUBJECTS: Four cases of membrano-bulbo-urethral junction (MBUJ) stenosis, seen between September 1995 and April 1996, are described. Two boys had previous successful valve resection but still showed extreme ballooning of the posterior urethra. The other 2 boys showed bladder instability on urodynamics and the male variant of the spinning top urethra on voiding cystourethrography (VCUG). RESULTS: All cases were successfully treated by endoscopic incision at the 12 o'clock position of the kink between the posterior and the penile urethra which is seen when the full bladder is expressed. Disproportion in the posterior urethra, seen on VCUG, together with bad urinary flow measured on uroflowmetry raise the suspicion of MBUJ stenosis. CONCLUSION: Although rarely seen, extreme caliber disproportion in the male urethra can cause obstruction. Ballooning of the posterior urethra, caused by urethral valves, bladder instability resisted by voluntary sphincter contraction or congenital posterior urethral dilatation, creates an obstructive kink in the urethra comparable to some obstructions in ureteropelvic junction stenosis. If suspicion of such a form of obstruction arises, cystoscopy during pressure on the full bladder is mandatory in order to see the obstruction, descending as a membrane from the vault of the urethra. 相似文献