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991.
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
992.
This paper reexamines the Brody effect, both in the far-field and in the near-field approximation. It stresses the fact that near an inhomogeneity the Brody factor is not a constant but a function of space. A full documentation of this function for realistic values of the inhomogeneity as relevant to electrocardiography is included. The existence of a zone having "anomalous" Brody factors is demonstrated. Moreover, the importance for this problem of the zero reference point is stressed. 相似文献
993.
Dipl.-Phys. B. Dierberger M. Schäch I. Anadere M. Brändle R. Jacob 《Basic research in cardiology》1991,86(6):561-566
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which may lead to a better oxygen supply.Supported by the Alfred-Teufel-Stiftung.This study is part of the unpublished doctoral thesis of M. Schäch 相似文献
994.
C. L. Goh 《Contact dermatitis》1991,24(2):81-85
The effect of repeated exposure of cutting oil on 8 guinea pigs' skin was evaluated by visual scoring for erythema and skin water vapour loss (SVL) measurement over a 6-week period. The visual scores (measuring severity of erythema) and SVL values were significantly higher on skin treated with cutting oils (positive control) compared to untreated skin (negative control) throughout the study period. The scores and SVL values returned to near-baseline values when cutting oil application was stopped. In addition, the effect of 2 "after-work" emollient creams on 8 guinea pigs' skin repeatedly treated with a cutting oil was assessed by similar methods. The visual scores and SVL values of guinea pig skin that was repeatedly treated with the cutting oil and moisturized with "after-work" emollient creams, were significantly higher than negative and positive control guinea pig skin. It appeared that the 2 "after-work" emollient creams do not alleviate the irritant effect of the cutting oil on guinea pig skin. They appeared to aggravate the irritant effect of the cutting oil. 相似文献
995.
H. Liedholm E. Wåhlin-Boll A. Hanson I. Ingemarsson A. Melander 《European journal of clinical pharmacology》1982,21(5):417-419
Summary The concentrations of real and apparent (= real hydralazine + acid-labile hydrazones) hydralazine in maternal and umbilical plasma obtained at delivery of 6 women treated with hydralazine and atenolol for pregnancy hypertension were measured by gas chromatography. In one of the patients, the concentrations of the same substances were subsequently measured in breast milk. Apparent hydralazine reached higher levels in umbilical than in maternal blood. The concentration of real hydralazine seemed to be at least as high in the fetus as in the mother. On the other hand, even though the fraction of real (i.e. presumably active) hydralazine was greater in milk than in plasma, the total concentration was smaller, and the estimated dose per milk feed of 75ml would not exceed 0.013mg. Thus, hydralazine treatment of the pregnant woman would expose her fetus to effective concentrations of the drug, but breast feeding would not result in a clinically relevant concentration in the infant. 相似文献
996.
John Fitzpatrick Arvind Bhargava Ramez Bedwani Marcel Gagnon 《Journal of surgical oncology》1981,16(1):37-41
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
997.
Nancy Telfer Yeu-Tsu N. Lee Quenious Merrill Franz K. Bauer 《Journal of surgical oncology》1981,16(2):159-165
The red blood cell (RBC) uptake of rubidium-86 (Rb-86), a sensitive in vitro test of RBC membrane transport, was measured in 22 controls, 8 patients with benign breast lesions, and 30 stage I/II, 13 stage III/IV untreated breast cancers. Total Rb-86 transport was measured. Following ouabain block, passive transport was determined, allowing calculation of active Rb-86 uptake by difference. There was a significant decrease in total and passive uptake by RBCs from patients with breast cancer when compared to controls and those with benign lesions (total uptake 58.6 ± 6.1% versus 63.6 ± 3.9%, P < 0.01; passive uptake 38.7 ± 6.8% versus 42.7 ± 4.6%, P < 0.02). The Rb-86 uptake returned towards normal in successfully treated stages-II-to-IV patients. There were no correlations with the patient's age, hematocrit, or incubation hematocrit with RBC Rb-86 uptakes. Results from incubation in Krebs-Ringer solution were not consistent with a plasma blocking factor. The RBC potassium content was slightly increased in the cancer patients. This, along with decreased passive transport, eliminates the nonspecific malfunction of the Na-K-pump as an explanation, and suggests that the decreased uptake is a cancer-related phenomenon. 相似文献
998.
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
999.
Michele Baccarani Giovanna Corbelli Sante Tura S. Tura G. Corbelli M. Fiacchini M. Gobbi L. Gugliotta F. Lauria P. Ricci A. Zaccaria M. Baccarani F. Mandelli G. Alimena G. Papa L. Annino G. Guglielmi A. Allegra 《Leukemia research》1981,5(2):149-157
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
1000.
Regional cerebral blood flow was measured with the intra-arterial 133 Xenon clearance technique using a multidetector device in 11 patients undergoing carotid angiography (with normal findings). During the flow studies the patients were awake and strict resting conditions were observed. The patients did not move or speak, and sensory stimulation were kept at a minimum. It was confirmed that the distribution of the grey matter blood flow showed a hyperfrontal pattern, the flow in frontal regions being significantly (20-40%) higher than in postcentral, occipital and temporal regions. There were no technical factors or morphological features of the telencephalon which could explain this difference. It was also shown that the distribution of the white matter flow and the relative weight of the grey matter corresponded in general to hemisphere morphology. Since in normal nervous tissue the blood flow is regulated by the neuronal activity, the following interpretation is given of the main finding. The hyperfrontal flow distribution of the grey matter (cortical) flow during resting wakefulness shows that there is a high activity in frontal "efferent" (motor-behavior) regions. At the same time there is a low activity in post-central and temporal "afferent" (sensory-gnostic) cortical areas. The high frontal activity suggests that in the resting conscious state--unaccompanied by movements, speech or behavioral reactions--the brain is active with an anticipatiory "simulation of behavior". The low postcentral flow, on the other hand, may possibly be related to a global inhibition of the sensory input. Several clinical as well as general biologic arguments are forwarded to support this interpretation. It is further pointed out that the hyperfrontal distribution of the resting activity in the cerebral cortex correlates to the resting EEG, in which lower frequencies (the alpha rhythm) predominate in postcentral and temporal regions where there is a low flow/activity, and high frequencies in frontal areas where the blood flow is high. This is in agreement with the finding that the blood flow and metabolism of the brain correlate to the EEG frequency content. 相似文献