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1.
P N Bretan D B Vigneron H Hricak G M Collins D C Price E A Tanagho T L James 《The Journal of urology》1987,137(1):146-150
To evaluate the role of magnetic resonance spectroscopy (MRS) and to develop surface coils for assessing cadaveric renal viability during hypothermic storage, we used the monophosphate/inorganic phosphate ratio (MP/Pi) to monitor phosphorous metabolites in intact kidneys during various renal preservation maneuvers. Eighteen canine kidneys and 16 cadaveric kidneys were studied as follows: Group 1 (N = 4) in situ kidneys were monitored by implanted MRS coils; Group 1 (N = 4) ex vivo kidneys were immediately attached to vascular cannulas and monitored by MRS surface coils during normothermic perfusion; Group 3 (N = 4) kidneys were removed, cold-flushed and, after 24 hours of 4C storage, monitored by MRS surface coils before and during four hours of reperfusion via vascular cannulas; Group 4 (N = 6) kidneys were removed, cold-flushed and monitored by surface coils during cold storage up to 72 hours. In addition, 16 cadaveric kidneys were studied while in sterile cold-storage containers. Postoperative renal function was followed in recipient patients. The MP/Pi ratios in Group 1 kidneys correlated with the ability to regenerate adenosine triphosphate (ATP). Groups 2 and 3 showed similar regeneration of ATP and MP/Pi after postischemic reperfusion, and the signal-to-noise ratios of the surface coils were better than those in the implanted coils in Group 1. Surface-coil monitoring in Group 4 kidneys showed predictable decay rates of MP/Pi during one to 72 hours of cold storage; in contrast, simultaneous cortical medullary microcirculation studies with 99mTc-macroaggregated albumin were inconclusive. Human cadaveric kidneys with high MP levels were associated with excellent renal function after transplantation, while those with low MP (less than or equal to 0.50) were associated with nonviability. We conclude that MRS is a practical and safe diagnostic modality for clinical transplantation. 相似文献
2.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
3.
Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
4.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation 相似文献
5.
Differential pattern of DNA-aneuploidy in human malignancies 总被引:5,自引:0,他引:5
Th Büchner W Hiddemann B Wörmann B Kleinemeier J Schumann W Göhde J Ritter K.-M Müller DB von Bassewitz A Roessner E Grundmann 《Pathology, research and practice》1985,179(3):310-317
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
P Labrude P Mouelle P Menu C Vigneron E Dellacherie M Leonard J L Tayot 《The International journal of artificial organs》1988,11(5):393-402
The usefulness of hemoglobin solutions as oxygen transporters is limited by their high affinity for oxygen and rapid elimination from the circulation. Various chemical modifications of hemoglobin aimed at overcoming these two handicaps have been suggested. We have developed a conjugate of pyridoxylated human hemoglobin with monomethoxypolyoxyethtylene 1900, whose preparation and properties are described. We present comparative results on short-term or definitive survival of Wistar rats which, during hemorrhagic shock due to the loss of 60 or 80% of their blood mass, were given a solution of native or modified hemoglobin, in some cases purified by ion-exchange chromatography to remove non-heme proteins, lipids, and some endotoxins. The more complex the treatment used to improve the properties and the purity of the hemoglobin solutions, the longer the animals survived. The loss of hemoglobin in the urine was greatly reduced after conjugation: after 20 h, less than 6% of the total infused. 相似文献
7.
8.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
9.
We have studied the in vitro interactions versus some blood components of the hemoglobin niosomes whose preparation and physicochemical and oxyphoric properties have been published in a precedent paper (this journal, 1989, No. 7, p. 192). This work was devoted to the research of 1) Agglutination phenomena with ABO blood group substances, plasma, some of its components and three plasma expanders, finally main erythrocytic phenotypes. 2) Adsorption of plasma proteins by immunoelectrophoresis. 3) Effects of niosomes on blood coagulation by thromboelastography. 4) Interactions between niosomes and phagocytes by electron microscopy, chemotactic migration, oxygen consumption, superoxide generation and oxydases function. These assays allow to observe and conclude that: 1) The agglutination phenomena are almost constant except with red blood cells. The agglutinates are dissociable by shaking. The agglutination appears to be nonspecific of a niosome component but is not observed with "classical" DPPC-chol-DCP liposomes. 2) Albumin and eventually transferrin are adsorbed at the surface of niosomes but without destabilizing them. 3) The vesicules show no important effects on coagulation factors, the enhancement of clotting time appearing essentially the consequence of blood dilution. 4) Niosomes phagocytosis is important but all the measurements fail to show any cellular metabolism activation: cell oxygen consumption, oxygenated metabolites generation and oxydases activity are not enhanced whatever the "electric" charge or the niosomes/phagocytes ratio used. 相似文献
10.
Influence of inhaled corticosteroids on growth: a pediatric endocrinologist''s perspective 总被引:7,自引:0,他引:7
DB Allen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(2):123-129
Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented. 相似文献