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71.
PETER A. GREENWOOD RICHARD J. LILFORD 《BJOG : an international journal of obstetrics and gynaecology》1986,93(3):260-263
Summary. One of the arguments used in favour of epidural analgesia for hypertensive patients in labour is its effect on mean arterial blood pressure, although the fetal and maternal risk from hypertension is more closely linked to maximum recorded levels. We have therefore assessed the effect of epidural analgesia on maximum blood pressure. There was no change in the maximum systolic or diastolic blood pressure after epidural analgesia when compared to baseline values or levels in untreated hypertensive controls. We conclude that this form of analgesia should be offered to hypertensive patients purely for its analgesic effect and not as a method for blood pressure control. 相似文献
72.
The presence of tinnitus in pregnancy was investigated by a postal questionnaire survey. A group of pregnant women attending the ante-natal clinic and a control group of non-pregnant members of the nursing staff at the Royal United Hospital in Bath were studied. The prevalence of tinnitus in the pregnant and non-pregnant women was compared. Both groups were similar in age, previous noise exposure and the presence of ear disease or operations. Twenty-five per cent of the pregnant women reported tinnitus compared with 11% of the control group. Chi-square analysis of this data gives a value of χ2= 4.07, d.f. = 1, P < 0.05. The result of our survey shows that there is a significantly increased prevalence of tinnitus in pregnant women compared with a similar non-pregnant control group. This association has not been previously reported. 相似文献
73.
JOHAN C. H. GENTZ RICHARD WARRNER BENGT E. H. PERSSON MARVIN CORNBLATH 《Acta paediatrica (Oslo, Norway : 1992)》1969,58(5):481-490
Blood glucose, plasma insulin, FFA and β-hydroxybutyrate values during intravenous glucose tolerance were reported in 20 small for gestational age (SGA) and 15 appropriate for gestational age (AGA) low birthweight infants. The babies were divided into three groups according to their age when tested; <24 hours, 24–48 hours and >48 hours. Both the SGA and AGA infants cleared glucose more rapidly with increasing age. The change was more marked in the SGA babies. The clearance rates were similar to those reported in normal full-sized infants. The insulin values before the glucose load were similar in all groups and comparable to those reported in normal newborn infants. The insulin response to glucose was variable. There were no significant differences with increasing age or between the two groups of infants. The insulin curve of the individual infant followed one of three patterns. Most commonly seen was a double-peak curve. The infants who showed a single-peak insulin response had a better but not significantly different glucose tolerance than that of the other babies. Infants with no appreciable insulin response still removed glucose from plasma at a rate similar to those with a double-peak insulin curve. It is concluded that insulin as measured in peripheral plasma could not explain the rate of removal of glucose from the plasma of the newborn low birthweight infant. Infants of low birthweight had higher plasma FFA values as compared to that reported in normal full term infants. The FFA values in SGA infants were higher than those in AGA babies. In both groups of infants, the jS-hydroxybutyrate values were comparable to those reported in normal full-term babies. Thus there was an unexpected discrepancy between the high FFA and relatively low β-hydroxybutyrate levels in plasma. The fall in plasma FFA and β-hydroxybutyrate after glucose was minimal but similar in both groups of infants. The findings are compatible with a decreased sensitivity to insulin in the infants studied. 相似文献
74.
Gross and Microscopic Changes Associated with a Nonthoracotomy Implantable Cardioverter Defibrillator 总被引:1,自引:1,他引:0
ANDREW E. EPSTEIN PETER G. ANDERSON G. NEAL KAY SHARON M. DAILEY VANCE J. PLUMB RICHARD B. SHEPARD 《Pacing and clinical electrophysiology : PACE》1992,15(4):382-386
The pathology associated with an invesrigational transvenous defibriliating and sensing lead is described. The lead system had delivered a total of 865 J from the time of implantation to the time of patient death from a noncardiac cause 7 months after implantation and 1 month after his last defibrillator shock. There was mild, superficial fibrous thickening on the endothelial surface of the superior vena cava adjacent to the proximal spring electrode, which did not extend into the vessel wall. The distal portion of endocardial lead was embedded in the interventricular septum near the apex of the right ventricle, surrounded by fibrous thickening, and partially covered by endocardial tissue. Microscopically, there was a thick bed of fibrous connective tissue surrounding the lead with extensive interstitial fibrous connective tissue radiating into the adjacent myocardium. Since this pattern is different from the more generalized fibrotic scarring produced by myocardial infarction, we speculate that the mechanism for the observed interstitial fibrosis is replacement fibrosis following acute myocyte injury that resulted from prior defibrillator shocks and possibly from the trauma produced by the lead compressing adjacent myocardium during systole. Potential effects on device efficacy of these fibrotic changes at the bioelectric interface include their representing a new arrhythmia substrate, the possibility that fibrosis could increase both defibrillation and pacing thresholds, and that the inflammatory reaction may cause deterioration of intracardiac electrograms and interfere with sensing and tachycardia recognition. 相似文献
75.
Abstract. A case of visceral leishmaniasis is presented, where a pre-existing polycythemia vera obscured signs of the infection. Visceral leishmaniasis is a life-threatening but curable protozoan infection of the reticuloendothelial system. We wish to report a case where symptoms and signs were obscured by a preexisting hematologic disease, polycythemia vera. 相似文献
76.
ALAN D. BERNSTEIN A. JOHN CAMM JOHN D. FISHER ROSS D. FLETCHER R. HARDWIN MEAD ANTHONY W. NATHAN VICTOR PARSONNET ANTHONY F. RICKARDS NICHOLAS P.D. SMYTH RICHARD SUTTON PETER P. TARJAN 《Journal of interventional cardiology》1993,6(3):235-239
BERNSTEIN, A.D., et al .: The NASPE/BPEG Defibrillator Code. A new generic code, patterned after and compatible with the NASPE/BPEG Generic Pacemaker Code (NBG Code) was adopted by the NASPE Board of Trustees on January 23, 1993. It was developed by the NASPE Mode Code Committee, including members of the North American Society of Pacing and Electrophysiology (NASPE) and the British Pacing and Electrophysiology Group (BPEG). It is abbreviated as the NBD (for NASPE/BPEG Defibrillator) Code. It is intended for describing the capabilities and operation of implanted cardioverter defibrillators (ICDs) in conversation, record keeping, and device labeling, and incorporates four positions designating: (1) shock location; (2) antitachycardia pacing location; (3) means of tachycardia detection; and (4) antibradycardia pacing location. An additional Short Form, intended only for use in conversation, was defined as a concise means of distinguishing devices capable of shock alone, shock plus antibradycardia pacing, and shock plus antitachycardia and antibradycardia pacing. (PACE, Vol. 16, September 1993) 相似文献
77.
Gender differences in relapse situations 总被引:1,自引:0,他引:1
78.
79.
YVES JANIN M.D. RICHARD STRAUSS M.D. SEYMOUR KATZ M.D. F.A.C.G. NORBERT PALTT M.D. IRWIN KATZKA M.D. F.A.C.G. LESLIE WISE M.D. 《The American journal of gastroenterology》1981,75(4):289-293
A patient with hypersplenism, who was found to have a splenic pseudocyst containing an organized hematoma, is described. There are only two patients with splenic pseudocyst and hypersplenism and an additional two patients with splenic cysts and hypersplenism reported in the world literature. The hypersplenism associated with splenic cysts and pseudocysts is explained on the basis of an expansion of the plasma volume and the total blood volume, an increased destruction of red blood cells and a pooling of blood in the enlarged spleen. The combined use of ultrasonography and computerized tomography has increased the accuracy of noninvasive diagnosis and made more invasive examinations unnecessary. When the ultrasound is technically unsuccessful or when it shows a mixed echo pattern, one should resort to computerized tomography with which it is possible, almost invariably, to differentiate between cysts and neoplasms. 相似文献
80.
RICHARD F. ROSENBHRG M.D. F.A.C.G. JAMES B. NAIDICH M.D. 《The American journal of gastroenterology》1981,76(1):59-69
Four cases of giant colonic diverticula are presented with emphasis on plain film recognition employing the "balloon sign", a persistent, rounded lucency which is consistently seen on any abdominal scout film or survey. The importance of this finding is even greater in the absence of gastrointestinal complaints in view of the complication of torsion and perforation 相似文献