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991.
During the period from August, 1977 to December, 1984, a total of 3003 patients who received open heart surgery were treated postoperatively at the ICU of National Cardiovascular Center. Low cardiac output syndrome (LOS) developed in 669 (22.3%) patients. Organ failures due to LOS were studied in these patients. Although the overall mortality of postoperative patients was 5.6% and improved to around 4% in the later years, death rate of patients with LOS was persistently high (22.8%) and showed no tendency to improve even in the latest years. Moreover, the clinical results of those LOS patients who developed organ failure were extremely poor; the mortality of patients with respiratory failure (RF) accounted for 36.8% and that of patients with other organ failure exceeded 50%. The incidence of impaired organs in LOS patients was 49.9% in RF, 29.9% in acute renal failure (ARF), 18.4% in hepatic failure (HF), 16.4% in disseminated intravascular coagulation (DIC), 15.5% in central nervous system failure (CNSF), and 11.1% in gastrointestinal bleeding (GIB). Pathophysiological mechanisms as well as the management of these major complications caused by LOS are also discussed. Some patients developed multiple organ failure (MOF). Plasma exchange (PE) was performed on 16 patients who developed MOF. Improvement of various organ functions was obtained and consequently three patients were successfully treated by means of PE. Removal of various substances toxic to organs, supplement of deficient substances and cessation of the vicious cycle produced by the interaction of impaired organs in patients with MOF are major roles of PE in the treatment of MOF. 相似文献
992.
Picosecond photochemistry of a cofacial diporphyrin containing iron(III) and zinc(II): Mimicking electron transfer between cytochrome c and the primary electron donor in reaction centers of photosynthetic bacteria 下载免费PDF全文
Fujita I Netzel TL Chang CK Wang CB 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(2):413-417
Comparison of picosecond kinetic and spectroscopic data for Zn octaethylporphine and Fe(III)Cl octaethylporphine with that for Zn—Fe(III)Cl, a cofacial diporphyrin composed of a Zn porphyrin covalently bound to an Fe(III)Cl porphyrin with two chains of five atoms each, supports the assignment of a light-driven electron transfer (k > 1011s-1) within Zn—Fe(III)Cl to form [Zn+·—Fe(II)]Cl. The kinetics (k ≈ 1010s-1) and thermodynamics of the reverse electron transfer are compared to those of a similar electron transfer in bacterial photosynthesis, the reduction of an oxidized bacteriochlorophyll dimer, (BChl)2+·, by Fe(II) cytochrome c. 相似文献
993.
Endothelin activates the dihydropyridine-sensitive, voltage-dependent Ca2+ channel in vascular smooth muscle. 总被引:16,自引:0,他引:16 下载免费PDF全文
K Goto Y Kasuya N Matsuki Y Takuwa H Kurihara T Ishikawa S Kimura M Yanagisawa T Masaki 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(10):3915-3918
Endothelin is a potent endothelium-derived vasoconstrictor peptide recently characterized from porcine and human vascular endothelial cells. Here we provide evidence that endothelin activates the dihydropyridine-sensitive, voltage-dependent Ca2+ channel in porcine coronary artery smooth muscle. The vasoconstrictor action of endothelin is efficiently antagonized by low doses of the dihydropyridine Ca2+-channel blocker nicardipine. Endothelin augments the Ca2+-induced contraction in a high-K+ depolarizing solution, markedly enhances high-threshold Ca2+-channel current on the whole-cell patch clamp recording, and causes a sustained increase in the intracellular Ca2+ that is largely dependent on extracellular Ca2+. These findings suggest that endothelin exerts its vasoconstrictor effect by either directly or indirectly activating the voltage-dependent Ca2+ channel. 相似文献
994.
T Nishimura M Sada H Sasaki N Yamada Y Yamada C Yutani H Amemiya T Fujita T Akutsu H Manabe 《Cardiovascular research》1989,23(7):561-566
Nuclear magnetic resonance (NMR) imaging was used to measure tissue sodium-23 in the myocardium undergoing cardiac rejection. In six dogs, the donor heart was heterotopically transplanted into the recipient's chest cavity. The dogs were then killed and sodium-23 images of the excised hearts were obtained using a high field (1.5 Tesla) NMR imaging system. Proton NMR imaging of each excised heart was also performed and T1, T2 relaxation times were calculated. Subsequently, these data were correlated with pathological findings of mild, moderate and severe rejection. The correlation coefficients between the rejection score and the T1, T2 relaxation times and sodium NMR signal intensity were 0.79, 0.70 and 0.84, respectively. Severely rejected areas of the myocardium were visualised by increased sodium NMR signals. These findings suggest that an increase of sodium NMR intensity is mainly caused by an increase of intracellular sodium content due to irreversible myocardial necrosis. Sodium NMR allows evaluation of the location and extent of rejection of myocardium after heart transplantation. 相似文献
995.
Refractory empyema occasionally reflects hidden malignant disease. We presented a rare case of rapidly progressive malignant mesothelioma of the pleura (MPM) mimicking empyema. Physicians should be aware of MPM when patients with empyema are refractory to the standard treatment, and PET‐CT may be helpful in establishing a precise diagnosis in such cases. 相似文献
996.
J Tanabe S Sasaki T Tamura R Okamoto R Sugamura H Fujita H Fukawa H Kanamori M Matsuzaki H Mohri 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(2):189-193
Myelodysplastic syndrome (refractory anemia with excess of blasts; RAEB) with marked basophilia and eosinophilia is described. An 82-year-old male was admitted to our hospital because of severe normocytic normochromic anemia (Hb 5.6 g/dl). The white cell count was 9,200/microliters with marked basophilia (34.5%) and eosinophilia (19.5%). The bone marrow aspiration also revealed both basophilia and eosinophilia, with blast contents of 9%. Diagnosis of RAEB was established. Although the treatment with red cell transfusion and ubenimex (Bastatin) was started, anemia was not improved. A karyotype of the bone marrow cells from this patient showed 47, XY, +8, i (17q), which has been observed as additional chromosomal abnormalities in blastic crisis of chronic myelogenous leukemia. The diagnosis of CML was not compatible with this case, because Ph1 chromosome and bcr gene rearrangement were negative. It is concluded that eosinophilia and basophilia might be derived from clonal abnormalities associated with MDS. 相似文献
997.
Retardation of skeletal development and cervical abnormalities in transgenic mice expressing a dominant-negative retinoic acid receptor in chondrogenic cells 下载免费PDF全文
Masahiro Yamaguchi Mika Nakamoto Hiroaki Honda Toshiyuki Nakagawa Hiroshi Fujita Takashi Nakamura Hisamaru Hirai Shuh Narumiya Akira Kakizuka 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(13):7491-7496
Skeletal formation is a fundamental element of body patterning and is strictly regulated both temporally and spatially by a variety of molecules. Among these, retinoic acid (RA) has been shown to be involved in normal skeletal development. However, its pleiotropic effects have caused difficulty in identifying its crucial target cells and molecular mechanisms for each effect. Development of cartilage primordia is an important process in defining the skeletal structures. To address the role of RA in skeletal formation, we have generated mice expressing a dominant-negative retinoic acid receptor (RAR) in chondrogenic cells by using the type II collagen α1 promoter, and we have analyzed their phenotypes. These mice exhibited small cartilage primordia during development and retarded skeletal formation in both embryonic and postnatal periods. They also showed selective degeneration in their cervical vertebrae combined with homeotic transformations, but not in their extremities. The cervical phenotypes are reminiscent of phenotypes involving homeobox genes. We found that the expression of Hoxa-4 was indeed reduced in the cartilage primordia of cervical vertebrae of embryonic day 12.5 embryos. These observations demonstrate that endogenous RA acts directly on chondrogenic cells to promote skeletal growth in both embryonic and growing periods, and it regulates the proper formation of cervical vertebrae. Furthermore, RA apparently specifies the identities of the cervical vertebrae through the regulation of homeobox genes in the chondrogenic cells. Great similarities of the phenotypes between our mice and reported RAR knockout mice revealed that chondrogenic cells are a principal RA target during complex cascades of skeletal development. 相似文献
998.
Kensuke Kojima Takashi Sawada Masaki Yasukawa Yoshinubu Matsuo Yoshihiro Yakushijin Hiroshi Narumi Taichi Azuma Hidetaka Takimoto & Masamichi Hara 《British journal of haematology》1998,100(3):567-570
We describe the first case of T-cell prolymphocytic leukaemia (T-PLL) in which the peripheral blood cells contained a human T-lymphotropic virus (HTLV) related tax sequence. Serum screening tests for anti-HTLV-I/II antibodies were negative. Polymerase chain reaction disclosed the presence of an HTLV-I tax sequence in the peripheral blood. Other sets of oligonucleotide primers for HTLV-I gag , pol , env and the long terminal repeat regions and for the HTLV-II pol region were negative in the DNA of the cells. Although patients with T-PLL have been reported to be seronegative for HTLV-I, our findings point to the possibility that HTLV-I infection might be involved in the aetiology of at least some cases of T-PLL and that there may be alternative mechanisms involved in HTLV-associated leukaemogenesis. 相似文献
999.
A Takahashi M Takasugi Y Utsunomiya M Akiyama H Hirose H Masaki A Iwagaki K Watanabe K Ahmed M Tao 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》1992,66(7):956-963
Eighty-seven oropharyngeal isolates of Haemophilus influenzae were obtained by two time cultures six months apart from a total of 288 children who attend a kindergarten. We analyzed the strains by comparing their serotypes, biotypes, beta-lactamase activity and by performing electrophoresis of outer membrane proteins on polyacrylamide gels. Only nineteen strains were not identical, the rest of the 68 strains were classified into 23 types. During 6 months at least 15 types of strains lost from this group and 21 types of new strains were obtained. There were no children who had identical pairs of H. influenzae in their oropharynx during the 6 months. The classification of strains in oropharynx suggested that person-to-person transmission of nontypable H. influenzae can occur. We concluded that oropharyngeal colonization by nontypable H. influenzae is not a normal flora in children. 相似文献
1000.
Colonic endoscopic mucosal resection in patients taking anticoagulants: Is heparin bridging therapy necessary? 下载免费PDF全文