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31.
Examining interspecies differences in response to ambient pollutantsis an essential component of risk assessment. The potentialhazard to public health from the inhalation of acid sulfateaerosols is of current concern. A significant biological targetis the pulmonary macrophage, which provides a primary defenseof the respiratory region of the lungs. One essential functionof these cells is phagocytosis of particles. This study assessedthe effects of acidic environments on the phagocytic activityof pulmonary macrophages obtained by lavage from humans andthree species of laboratory animals commonly used in acid aerosoltoxicology studies, namely, rats, rabbits, and guinea pigs.Cells were incubated with polystyrene latex particles in mediaacidified by addition of sulfuric acid. The percentage of cellswhich were phagocytic, as well as the relative number of particlesingested by these cells, was found to decrease with increasingacidity for all species. The ranking of response in order ofdecreasing sensitivity to acidic challenge was as follows: guineapig>rat>rabbit>human. 相似文献
32.
33.
Endoscopic Diagnosis of a Giant Esophageal Leiomyosarcoma 总被引:1,自引:0,他引:1
EDWARD K. PARIYKA M.D. ROBERT A. SANOWSKI M.D. RICHARD A. KOZAREK M.D. 《The American journal of gastroenterology》1981,75(2):132-134
A giant polypoid lesion of the cervical esophagus was discovered on barium swallow in a patient with minimal dysphagia. Endoscopy revealed a whitish, polypoid intraluminal mass with superficial ulcerations and mucosal biopsies, necrotic epithelium plus spindle cells consistent with leiomyoma. At exploration, a leiomyosarcoma with microvascular invasion was excised. The clinical features and value of endoscopic biopsies are reviewed for this and other cases reported in the literature. 相似文献
34.
RICHARD L.B. MILEK WILL F.G. ROEFFEN CLEMENS H.M. KOCKEN JOSEPHINE JANSEN ANITA M. KAAN WIJNAND M.C. ELING ROBERT W. SAUERWEIN & RUUD N.H. KONINGS 《Parasite immunology》1998,20(8):377-385
A precondition for the development of a transmission blocking vaccine based on the sexual stage-specific surface antigen Pfs48/45 of Plasmodium falciparum is its heterologous synthesis in a native state. Here we describe the production of recombinant Pfs48/45 in Escherichia coli . Two recombinant proteins, of which one is a glutathione-S-transferase fusion protein, were produced. Enzyme-linked immunosorbent assays showed that at least a subfraction of the recombinant proteins had a conformation capable of binding transmission blocking monoclonal antibodies. However, despite the fact that both proteins were very immunogenic, they did not induce transmission blocking immunity in mice or rabbits. Immunological studies with congenic mouse strains demonstrated that immune responses could be boosted with gametocyte extracts and were not restricted to a particular class II major histocompatibility complex haplotype . 相似文献
35.
Kiyoshi ITO Tatsuro AOYAMA Yoshinari MIYAOKA Tetsuyoshi HORIUCHI Kazuhiro HONGO 《Neurologia medico-chirurgica》2015,55(7):557-563
Cervical spinal neurinomas are benign tumors that arise from nerve roots. Based on their location, these tumors can also take the form of a dumbbell-shaped mass. Treatment strategies for these tumors have raised several controversial issues such as appropriate surgical indications and selection of surgical approaches for cervical dumbbell-shaped spinal neurinomas. In this report, we review previous literature and retrospectively analyze cervical spinal neurinoma cases that have been treated at our hospital. Surgical indications and approaches based on tumor location and severity are discussed in detail. Thus, with advances in neuroimaging and neurophysiological monitoring, we conclude that appropriate surgical approaches and intraoperative surgical manipulations should be chosen on a case-by-case basis. 相似文献
36.
Evaluation of a Flexible Endoscope for Laparoscopy 总被引:1,自引:0,他引:1
ROBERT A. SANOWSKI M.D. F.A.C.G. RICHARD A. KOZAREK M.D. EDWARD K. PARTYKA M.D. 《The American journal of gastroenterology》1981,76(5):416-419
Thirty patients underwent diagnostic laparoscopy using an unmodified Olympus GIF-P2 fiberendoscope. Both feasibility and safety of the fiberoptic instrument were evaluated. Compared to conventional laparoscopy, a greater area of the peritoneal cavity was visualized, and biopsies and photographs were successfully obtained. There were neither mechanical nor infectious complications. As has occurred in other areas of endoscopy, use a flexible instrument for laparoscopy appears to offer advantages over conventional rigid laparoscopes. 相似文献
37.
Summary. Peripheral blood stem cell autografts for the treatment of chronic myeloid leukaemia (CML) are currently under evaluation. A patient with CML received intensive chemotherapy followed by granulocyte colony-stimulating factor prior to the collection of peripheral blood derived stem cells. He developed unusually severe, and fatal, hypophosphataemia and this coincided with the rapid rise of his peripheral blood white cell count. The hypophosphataemia was considered to be due to a combination of severe anorexia, sepsis and the rapid growth factor-stimulated myeloid regeneration in CML. 相似文献
38.
Circulating Megakaryocytes and Platelet Release in the Lung 总被引:8,自引:1,他引:8
1. Megakaryocytes were demonstrated in central venous blood of each of23 patients who underwent cardiac catheterization. Cell counts ranged from0.7 to 5.9 megakaryocytes per ml. of blood; the equivalent of one-third ofthese cells were considered to contain a full complement of cytoplasm. It hasbecome evident that megakaryocytes are normal constituents of blood.2. In an attempt to quantify megakaryocyte migration from the bone marrow it was calculated that from 20-50 per cent of the mature megakaryocytepopulation enters the blood and ultimately reaches the lungs. The possibilitythat all megakaryocytes migrate from the marrow is not precluded with certainty by these studies.3. It was estimated that from 7-17 per cent of the bodys platelets are released in the pulmonary capillaries. If all megakaryocytes migrate from thebone marrow, then as much as 33 per cent of the platelet population is delivered to the blood in the lungs. Submitted on January 15, 1965 Accepted on March 13, 1965 相似文献
39.
A method for the preparation of I131-labeled anti-D eluates (I[unknown] anti-D)specific for the D antigen by adsorption and elution from intact D positivered cells is presented. A standard D antigen reference system for the quantitative comparison of the red cell D antigen from various donors was developedon the basis of kinetic studies of the effect of pH, temperature and antigenconcentration on the I[unknown] anti-D reaction with the D antigen. The red cell Dantigen determinations of the blood from 33 Negro and 102 Caucasiandonors showed wide monomodal frequency distributions which indicate aheterogeneity of quantitative D antigen reactivity consistent with previousserologic and I131-labeled anti-D studies. The average red cell D antigenreactivity of the 20 probable D homozygote and 14 established D hemizygoteCaucasian donors was similar to the D antigen reactivity of the 102 randomCaucasian donors. The red cell D antigen reactivity was strongly depressedby the C antigen (or C gene) in Caucasian bloods and enhanced by the Eantigen (or E gene) in Negro bloods. The E antigen (or E gene) may alsohave enhanced the D antigen reactivity in red cells from Caucasian donors,but the difference in D zygosity provides an alternative explanation for theresults. The marked influence on red cell D antigen reactivity in the presenceof the C and E antigen may well have obscured any lesser influence of Dzygosity. Accepted on December 6, 1962 相似文献
40.
JACQUES M.T. DE BARKER Ph.D. RICHARD N.W. HAUER M.D. PATRICIA F.A. BAKKER M.D. ANTON E. BECKER M.D. MICHIEL J. JANSE M.D. ETIENNE O. ROBLES DE MEDINA M.D. 《Journal of cardiovascular electrophysiology》1994,5(4):335-344
Abnormal Automaticity in Human Atrium, introduction: A 32-year-old woman was operated upon because of drug refractory atrial tachycardia.
Methods and Results: Electrophysiologic study was performed prior to operation. During surgery, epicardial mapping of the electrical activity of the left atrium was performed. The left atrial appendage was resected and studied in a tissue bath. Thereafter, histologic examination was performed. Polarity of the P wave in the surface ECG suggested that the tachycardia originated high in the left atrium. Epicardial mapping disclosed earliest activation in the apex of the left atrial appendage. Intracellular recordings from surgical specimen made at the site of origin, which was marked during surgery, revealed cells with phase 4 depolarization at cycle lengths ranging from 360 to 540 msec. Exit block prevented spread of activation from the spontaneously firing cells to surrounding tissue. Histology showed that spontaneous activity arose in an area with abnormal cells-characterized by an amorphous, pale eosinophilic staining cytoplasm and absence of nuclei-surrounded by normal myocytes.
Conclusion: The observations indicate that the mechanism of the atrial tachycardia was based on abnormal automaticity in an area consisting of a conglomeration of normal and abnormal myocytes. 相似文献
Methods and Results: Electrophysiologic study was performed prior to operation. During surgery, epicardial mapping of the electrical activity of the left atrium was performed. The left atrial appendage was resected and studied in a tissue bath. Thereafter, histologic examination was performed. Polarity of the P wave in the surface ECG suggested that the tachycardia originated high in the left atrium. Epicardial mapping disclosed earliest activation in the apex of the left atrial appendage. Intracellular recordings from surgical specimen made at the site of origin, which was marked during surgery, revealed cells with phase 4 depolarization at cycle lengths ranging from 360 to 540 msec. Exit block prevented spread of activation from the spontaneously firing cells to surrounding tissue. Histology showed that spontaneous activity arose in an area with abnormal cells-characterized by an amorphous, pale eosinophilic staining cytoplasm and absence of nuclei-surrounded by normal myocytes.
Conclusion: The observations indicate that the mechanism of the atrial tachycardia was based on abnormal automaticity in an area consisting of a conglomeration of normal and abnormal myocytes. 相似文献