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991.
The cause of female urethral instability is still controversial. With the help of this retrospective analysis of 1168 continuous long-term recordings of the intraurethral pressure at the maximum point of urethral pressure, the correlation between pressure variations (UPV) and simultaneous bladder instability was investigated. It could be stated that clinically important UPV (more than 15 cmH2O) are found more often in women who suffer from signs of bladder instability (defined as low bladder compliance combined with uninhibited detrusor contractions and/or urinary leakage) than in patients without signs of unstable bladder.  相似文献   
992.
The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2). Measurements of SpO2 were taken at 1, 5, 10 min, and 24 hr after delivery. At one and five minutes, SpO2 recorded from the right hand was higher than that recorded from the lower extremities (71.9% +/- 6.5% vs 63.4% +/- 4.3% and 83.3% +/- 4.2% vs 76% +/- 4.1%, mean +/- SD, respectively). At ten minutes these differences diminished, and had almost completely disappeared after 24 hr. These results can be explained by the presence of R-L shunting at the ductus arteriosus level, producing reduced SaO2 in the lower extremities. Oxygen saturation did not differ between neonates delivered vaginally or by Caesarean section, regardless of the presence or type of anaesthesia. We concluded that neonates remain relatively desaturated in the immediate postpartum period and that the SpO2 obtained from the right hand is a better index of neonatal oxygenation than that obtained from the heel.  相似文献   
993.
The hypothesis that histamine receptor (H1 and H2) blockade beneficially affects the hepatic oxygen supply-demand relationship was tested during experiments performed on 13 miniature pigs. Hepatic arterial and portal blood flows were measured with electromagnetic flowmeters. Cardiac output was determined by thermodilution. H1 and H2 receptor blockade was achieved with promethazine, 5 mg.kg-1 and cimetidine 30 mg.kg-1 IV, respectively. The study demonstrated no significant effect of H1 and H2 receptor blockade on hepatic oxygen uptake and no noticeable effects of cimetidine on hepatic circulation. However, promethazine decreased total hepatic blood flow, primarily by decreasing portal blood flow; this resulted in an increase in oxygen extraction as reflected in a decreased oxygen content in hepatic venous blood. The results reject the posed hypothesis: H1 receptor antagonist promethazine decreased, while H2 receptor antagonist cimetidine did not affect hepatic blood flow and oxygen supply; hepatic oxygen demand remained unaffected during H1 and H2 receptor blockade.  相似文献   
994.
Attitudes to autologous blood donation have been surveyed in a group of 38 postoperative bariatric patients. Only two patients (5%) declined to participate. Twenty-eight of 38 (70%) successfully predeposited autologous blood. Twenty-five of 28 donors (90%) had done so at the suggestion of their surgeon. Concern about contracting AIDS was the motivating factor in the majority of patients (21 patients, = 55%). Lack of infectious complications in general was cited by an additional four (11%). All respondents would donate autologous blood in the future, and would recommend the procedure to others who were about to undergo elective surgery. There was an increase from 29% to 50% who stated that, following their autologous donation experience, they would consider being homologous volunteer blood donors in the future.  相似文献   
995.
延髓吻端腹外测区(Rostral ventrolateral medulla,RVL)微量注射红藻氨酸(Kainic acid,KA)前,分别用弱、强电刺激“人中”穴时可引起动脉血压(BP)显著升高,心率(HR)明显增快。一侧或双侧RVL注射KA后,再用弱、强电刺激“人中”穴时,BP、HR的反应基本消失。结果表明,RVL在“人中”穴加压效应中起关键性作用。  相似文献   
996.
Methods for the acquisition and analysis of intracranial pressure (ICP) signals are reviewed from clinical and technical perspectives. The clinical importance of ICP monitoring is presented, and methods for ICP transduction are briefly discussed. These methods include intraventricular catheters, subarachnoid screws, epidural techniques, and the new fiberoptic ICP measurement systems. Approaches to the visual analysis of the ICP waveform are presented, with special emphasis on the relationship between the ICP waveform and the arterial blood pressure signal. Methods of computer-based ICP analysis are also reviewed, including histogram and systems analysis methods. Methods to predict ICP pressure rises and to estimate intracranial compliance are also discussed. Finally, ICP monitoring is reviewed from the point of view of patient outcome. It is concluded that advanced ICP waveform analysis methods warrant further clinical evaluation to demonstrate their clinical usefulness.  相似文献   
997.
Summary The influence of a diet rich in linseed oil (10 % in weight) with a content of 61.2 % of -linolenic fatty acid on blood pressure and complex blood viscosity was investigated in spontaneously hypertensive rats. A decrease in blood pressure by 59 mm Hg was found compared to the age-matched, untreated control group. The viscous () and elastic () components of viscosity were also reduced at various shear rates ( ). The same applies to the aggregation index, which is a measure of the aggregation tendency of red blood cells (RBC).Of course, the effects on blood viscosity cannot explain the observed degree of blood-pressure lowering. Nevertheless, a decrease in the viscosity can improve the flow conditions in the microcirculation, which may lead to a better oxygen supply.Supported by the Alfred-Teufel-Stiftung.This study is part of the unpublished doctoral thesis of M. Schäch  相似文献   
998.
Whole blood catalase levels were estimated using a disc flotation method in 209 random patients with a wide variety of malignancies. Fifty patients had received no treatment, and the remainder, although having undergone prior therapy, had recurrent or metastatic disease at the time of the study. No relationship was found between the presence of cancer and catalase levels. A direct relationship was found for catalase with hemoglobin levels in both normal and patients' samples. Whole blood catalase is of no value in diagnosis and monitoring of cancer. The decreased catalase values found here and reported previously by others are the result of low hemoglobin levels found in many patients with cancer.  相似文献   
999.
Evaluation of cell mediated immunity against human melanoma target cells was performed in an in vivo model using human tumor xenografts growing in Balb/c athymic mice. Intraperitoneal inoculation of 1 × 107 human melanoma cells produced peritoneal carcinomatosis which lead to death of the animals at 23.8 ± 2.6 days (N = 12). Peripheral blood lymphocytes (PBL) from normal donors were administered to tumor bearing mice, and survival times of 22.0±2.3 days were observed (N = 8). Peripheral blood lymphocytes from four of five normal donors which had been presensitized on monolayers of melanoma tissue culture cells in vitro failed to prolong host survival times. In contrast, PBL obtained from 15 of 20 melanoma patients were found to prolong survival of the tumor bearing nude mice. Of these 15 patients, 8 were undergoing specific active immunotherapy, while 7 had not been sensitized except by the disease process. The ability of PBL obtained from patients to prolong survival of tumor bearing animals did not appear to correlate with either the stage of the disease or the patient's clinical course. The possible mechanisms for the prolonged survival and usefulness of this model are discussed.  相似文献   
1000.
The effect of early splenectomy and of polychemotherapy with hydroxyurea, busulfan, and alternate bimonthly courses of arabinosyl cytosine and vincristine plus prednisone, was evaluated in 139 previously untreated patients with chronic myeloid leukemia (CML), consecutively admitted to 18 hospitals from March 1973 to October 1974. Fifty-six patients were splenectomized and 83 patients were not splenectomized. Splenectomy did not influence the duration of chronic and blastic phase, and did not prolong survival. The prognosis of high risk patients was not improved. During the chronic phase, high platelet counts were more frequent in splenectomy group, and five patients developed thrombotic or thromboembolic complications, 5 to 19 months after the operation. The median survival of the whole group was 50 months, with 32 of 139 patients (actuarial proportion 30%) remaining alive 72 months after diagnosis, but the slope of the survival curve was similar to that of historical controls. The results of this trial suggests that new strategies should be developed for the therapy of CML.  相似文献   
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