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91.
We successfully cured atrial fibrillation while preserving internodal conduction in a patient with a partial atrioventricular septal defect. Because the anterior and middle internodal tracts are interrupted by the defect, the lower right atrial incision of either the maze or the radial procedure may interrupt the remaining posterior tract, resulting in internodal conduction block. We deleted the posterior septal incision from the radial procedure and replaced it with a right-side left atriotomy. The patient resumed normal sinus rhythm with significant contraction of the right and left atria. The preserved internodal pathway through the posterior interatrial septum was confirmed by electrophysiologic study.  相似文献   
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Human T-cell leukemia virus type 1 (HTLV–1) is an etiologic agent of adult T-cell leukemia/lymphoma and other HTLV-1–associated diseases. However, the interaction between HTLV–1 and T cells in the pathogenesis of these diseases is poorly understood. Mouse cells have been reported to be resistant to cell-free HTLV–1 infection. However, we recently reported that HTLV–1 DNA could be observed 24 h after cell-free HTLV–1 infection of mouse cell lines. To understand HTLV–1 replication in these cells in detail, we concentrated the virus produced from c77 feline kidney cell line and established an efficient infection system. The amounts of adsorption of HTLV–1 are larger in mouse T cell lines, EL4 and RLml, than those in human T cell lines, Molt4 and HUT78, and are similar to that in human kidney cell line, 293T. Unexpectedly, however, the amounts of entry of HTLV–1 are about 10–fold larger in the two mouse cell lines than those in the three human cell lines employed. Moreover, viral DNA was detectable from 1 h in EL4 and RLml cells, but only from 2–3 h in 293T, Molt4 and HUT78 cells. However, the amount of viral DNA in EL4 cells became smaller than that in Molt4 cells. HTLV–1 expression could be detected until day 1–2 in RLml and EL4 cells, and until day 4 in Molt4 cells. Our results suggest that mouse cell experiments would give useful information to dissect the early steps of cell-free HTLV–1 infection.  相似文献   
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MDP-Lys (N2-[(N-acetylmuramyl)-L-alanyl-D-isoglutaminyl]-N6-stearoyl-L-lysine), a macrophage activator, is a lipophilic derivative of muramyl dipeptide (MDP). Multilamellar liposome incorporated MDP-Lys was prepared using phosphatidylcholine and phosphatidylserine by conventional film method, and its inhibitory effect on lung metastasis was compared with MDP-Lys as a solution in hamster's osteosarcoma. The lung metastatic rates after transplantation of the tumor to a lower extremity, in which the extremity was amputated 3 weeks later, were 50% and 100% 3 and 7 weeks, respectively, after transplantation. The rates after amputation were reduced by the treatment with MDP-Lys proportionally to the logarithmic MDP-Lys dose, and the rates 7 weeks after transplantation were 55% and 60%, respectively, in the MDP-Lys solution (50 microg/day) and liposomal MDP-Lys (20 microg twice/week) groups. Fifty percent of hamsters treated with liposomal MDP-Lys survived for more than 6 months. Considering that hamsters had a lung metastasis rate of 50% before MDP-Lys treatment, liposomal MDP-Lys given at a dose of 20 microg twice/week was effective for inhibiting lung metastasis at a far lower dose of MDP-Lys than that given as a solution (40 microg vs. 350 microg per week). No significant side effect of liposomal MDP-Lys, as evaluated by the comparison of body weight changes among differently treated hamsters, was detected. This greater inhibitory effect of liposomal MDP-Lys can be considered to be due to the longer retention of the liposomal form in the lung.  相似文献   
94.
Abstract: To analyze the autonomic nervous system during left heart bypass with a vibrating flow pump (VFP), fluctuations in hemodynamic derivatives were evaluated by the spectral analysis method using fast fourier transform methodology. After the left pleural cavity was opened through the fourth intercostal space under general anesthesia, a VFP was implanted as the left heart bypass device in chronic animal experiments using 3 healthy adult goats. Hemodynamic parameters with and without VFP assistance were recorded on magnetic tape in awake animals and were analyzed by computer through an analog to digital convertor. Power spectral analysis was performed on a beat-to-beat basis for the evaluation of the fluctuations. During left heart bypass with the VFP, Mayer wave fluctuations were decreased significantly although respiratory waves were not changed significantly. These results suggest that sympathetic nervous system modulation was changed under the influences of the left heart bypass with VFP. By using this analysis methodology, truly physiologic ventricular assistance may be achieved.  相似文献   
95.
Summary This is a follow-up study of the second consecutive series of 71 infants during the year of 1965 through 1970. Over-all mortality rate was 15.5 per cent. In the last two years, the result has improved markedly as exemplified by only one death occuring in 33 patients (3 per cent) operated. The striking decrease in the mortality rate during this period was mainly due to the intensive care of postoperative respiratory dysfunction and prevention of low cardiac output especially in infants under one year of age. Permanent heart block and complications of the central nervous system have not been observed in this series. In conclusion, patients with VSD and pulmonary hypertension should be advised to undergo radical operation even in early stage of infancy.  相似文献   
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Gefitinib has a modest activity in previously treated patients with advanced non-small cell lung cancer (NSCLC). However, the efficacy and safety of gefitinib monotherapy in untreated advanced NSCLC is not known. We retrospectively reviewed the records of 12 patients of NSCLC who were unfit or refused cytotoxic chemotherapy, and were treated with a single-agent gefitinib as first-line therapy in our hospital. The patients were 6 males and 6 females. The median age was 76.5 years (range 34-82). The histological types were adenocarcinoma in all patients. Clinical stage was IIB in one patient, IIIB in four, and IV in seven. Five were elderly patients and four were patients with ECOG PS (performance status) 3. Five had partial response (PR), and two had stable disease (SD). The response rate was 41%. The median time to progression (TTP) was 126 days. Grade 1 diarrhea was observed in three patients, grade 1 or 2 eruption paronychia was in eight, and grade 1 or 2 liver dysfunction was in two. No grade 3 or 4 toxicities occurred. Gefitinib monotherapy may provide an opportunity for untreated NSCLC, particularly unsuitable patients with standard chemotherapy. Prospective studies of gefitinib monotherapy as first-line treatment are warranted.  相似文献   
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