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Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery. Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group 2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4 mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves, and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive blood conservation programs in current pediatric open-heart surgery.  相似文献   
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We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc.  相似文献   
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A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well.  相似文献   
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Detection limit in low-amplitude EEG measurement.   总被引:1,自引:0,他引:1  
Electrocerebral inactivity for the determination of cerebral death is defined as no findings of EEG greater than the amplifier's inherent internal noise level when recording at increased sensitivity. A surface biopotential electrode contains two interfaces composed of skin gel (electrolyte) and gel electrode (metal), each forming a noise source. The power spectral density, S(f), of extremely low noise signals was obtained by means of autocorrelation and fast Fourier transformation. Interelectrode resistance, R(f), was measured with synchronous rectification. The formula of equivalent noise resistance R(n) = S(f)/4kT, where k is the Boltzmann constant and T is room temperature in Kelvin, gives a resistance that generates the thermal noise corresponding to the measured S(f). Rn/R is a parameter derived from normalization by R. When Rn/R = 1, measured noise contains thermal noise only. Meanwhile, Rn/R > 1 indicates presence of excess noise, such as 1/f, and tissue noise in addition to the thermal noise. Mean square root (Rn/R) of the scalp noise was 10.8 at 10 Hz, showing existence of excess noise. The study results suggest that it is necessary to take excess noise into consideration in the measurement of low-amplitude EEG for the determination of cerebral death.  相似文献   
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Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection.  相似文献   
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To evaluate coronary hemodynamics and myocardial perfusion, left coronary digital subtraction angiography (DSA) and Tl-201 myocardial scintigraphy were performed in patients with syndrome X. The coronary circulation time (CCT) was significantly prolonged after the injection of isosorbide dinitrate and contrast medium i.c. Apical T1/2 was also prolonged on ergonovine malate provocation test. We suspected that the vascular response of the coronary peripheral artery was impaired, and microvascular spasm probably existed in patients with syndrome X. The prevalence of abnormal myocardial perfusion defect on exercise Tl-201 SPECT in syndrome X was very high, and coronary hemodynamics was significantly disturbed in the group of syndrome X with abnormal Tl-201 SPECT. Tl-201 lung/heart count ratio significantly increased in syndrome X on treadmill test. Because of this, exercise induced left ventricular dysfunction was suspected. We concluded that the main pathophysiological finding of impaired coronary circulation in syndrome X was microvascular spasm.  相似文献   
20.
A series of 1 beta-methylcarbapenem compounds, which have a 5'-substituted-N-methylpyrrolidin-3'-ylthio group as a C-2 side chain, have been prepared and their biological properties were investigated. Substitution with a methyl group on the nitrogen atom in the C-2 side chain effectively enhanced stability to renal dehydropeptidase-I as well as introduction of methylene spacer between the aminocarbonyl group and the pyrrolidine ring of the 5'-aminocarbonylpyrrolidin-3'-ylthio group.  相似文献   
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