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91.
Tetsuo Hadama Yoshiaki Mori Osamu Shigemitsu Tatsunori Kimura Shinji Miyamoto Hidenori Sako Tooru Soeda Toshihide Yoshimatsu Yuzo Uchida 《Surgery today》1996,26(1):60-63
We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system. 相似文献
92.
Penetration of etoposide into human malignant brain tumors after intravenous and oral administration
Katsuzo Kiya Tohru Uozumi Hidenori Ogasawara Kazuhiko Sugiyama Takuhiro Hotta Takashi Mikami Kaoru Kurisu 《Cancer chemotherapy and pharmacology》1992,29(5):339-342
Summary Penetration of etoposide into the cerebrospinal fluid, brain tumor, and brain tissue after intravenous administration was investigated in patients presenting with malignant brain tumors. A relatively low dose (55–65 mg/m2) was used to compare intravenous with oral administration. High-performance liquid chromatography with fluorescence detection was used to evaluate drug levels. Plasma and cerebrospinal fluid levels of etoposide after oral administration (50–150 mg/day) were also studied so as to determine the adequate oral dose for the treatment of malignant brain tumors. The peak plasma concentration after intravenous administration ranged from 7.01 to 10.47 g/ml, varying in proportion to the injected dose, whereas that after oral administration was lower, namely, 1.44–4.99 g/ml, and was unstable when the oral dose was 150 mg daily. The peak cerebrospinal fluid level following either intravenous or oral administration was much lower than the plasma concentration and was influenced by the peak plasma level and the sampling site. The etoposide concentration in cerebrospinal fluid taken from the subarachnoid space and ventricle of patients displaying no tumor invasion and of those presenting with meningeal carcinomatosis and in cerebrospinal fluid taken from the dead space after tumor resection was 0.7%±0.5%, 3.4%±1.0%, and 7.2% ± 8.5%, respectively, of the plasma concentration. Serial oral administration did not result in the accumulation of etoposide in cerebrospinal fluid. The tumor concentration (1.04–4.80 g/g) was 14.0%±2.9% of the plasma level after intravenous administration, was related to the injected dose, and was approximately twice the concentration detected in the brain tissue. Therefore, a relatively low dose of etoposide injected intravenously penetrates the brain tumor at an efficacious concentration. Our results indicate than an oral dose of 100 mg etoposide be given for malignant brain tumors, as limited penetration of the drug into the intracranial region was observed. 相似文献
93.
N. Yagi 《Journal of muscle research and cell motility》1992,13(4):457-463
Summary The effects of N-ethylmaleimide (NEM) and other sulfhydryl modifiers on the structure of skinned frog skeletal muscles were studied using the X-ray diffraction technique. In sartorius muscle with full overlap between the thick and thin filaments, 0.1-1.0 mM NEM changed the intensity ratio of the (1,0) and (1,1) equatorial reflections from 4.35 to 0.72, and the (1,0) spacing of the hexagonal filament lattice from 40.4 to 41.4 nm. The axial X-ray diffraction pattern showed weak myosin layer-lines after the NEM treatment but enhancement of the actin layer-lines was not observed. In overstretched semitendinosus muscle, NEM did not affect the equatorial spacing but the myosin layer-lines were weakened. These results indicate that modification of myosin by NEM destroys the helical arrangement of myosin heads around the shaft of the thick filament and that when thin filaments are available, myosin heads move towards, and possibly bind to them. This binding is different from that in rigor since the ladder-like appearance of the higher actin layer-lines, which is typical of patterns from rigor muscles, was not observed. On removal of ATP after the NEM treatment, the diffraction pattern showed features characteristic of that from normal rigor muscles but no tension was produced. The pattern showed well-defined samplings on layer-lines in the small-angle region, indicating the presence of an extensive lattice order and exact axial alignment of the filaments. The first actin layer-line did not show samplings from the superlattice of the thick filaments, which are observed on the myosin layer-lines in patterns from resting muscles. This indicates that in NEM-treated rigor muscles the pattern of binding of myosin heads to the thin filaments is not influenced by the azimuthal orientation of the thick filament. 相似文献
94.
95.
96.
There are no published data of manometric studies of pyloric motor function in patients with infantile hypertropic pyloric
stenosis (IHPS). The present study attempted to examine the characteristics of motor abnormality of the pylorus in five children
with IHPS. Using a transducer-built-in manometric catheter cannulated through the pylorus under fluoroscopy, the pressure
in the pyloric canal was recorded continuously over 3 h during fasting. Clusters of high-amplitude spastic contractions of
over 300 mmHg were recorded at intervals. The frequency was 1–3/min (mean 1.7 cpm) and the duration was 7–15 s. These periodic
spastic contractions were suppressed temporarily for 20–30 min after intravenous injection of 0.01 mg/kg atropine. After pyloromyotomy,
these spastic contractions decreased remarkably in amplitude, but there were no changes in frequency. It is concluded that
the underlying motor abnormality observed in hypertrophied pyloric muscle is clusters of high-amplitude contractions, although
more precise measurements of basal pyloric pressure are needed to explore the pathophysiology of IHPS in detail. The effect
of pyloromyotomy may be related to the decrease in high-amplitude contractions.
Accepted: 26 May 1998 相似文献
97.
98.
Statistical Analysis of Factors Affecting the Outcome of Patients with Ruptured Distal Anterior Cerebral Artery Aneurysms 总被引:3,自引:0,他引:3
Miyazawa N Nukui H Yagi S Yamagata Z Horikoshi T Yagishita T Sugita M 《Acta neurochirurgica》2000,142(11):1241-1246
Summary
The clinical factors affecting the outcome of patients with ruptured distal anterior cerebral artery (ACA) aneurysms were
analyzed using multiple logistic regression analysis.
The medical records were reviewed of 52 patients (57 aneurysms) with ruptured distal ACA aneurysms operated on by the same
neurosurgeon over 25 years. The standard policy was early surgery for patients in Hunt and Kosnik grades I to IV. Age, sex,
Hunt and Kosnik grade, timing of operation, size of aneurysms, number of aneurysms, association of intracerebral haemorrhage
(ICH), intraventricular haemorrhage, and azygos ACA, use of temporary clipping , occurrence of premature rupture, and presence
of psychiatric change were investigated. Univariant analysis disclosed that clinical grade (P=0.0006), size of aneurysm (P=0.005),
and size of ICH (P=0.012) affected the outcome of patients. Multiple logistic regression analysis found that Hunt and Kosnik
grade (P=0.010) and timing of operation (P=0.033) affected the outcome. There was no significant relationship between long-term
outcome and clinical factors, although a close relationship was found with Hunt and Kosnik grade (P=0.071).
Clinical grade and timing of the operation affected the outcome of patients with ruptured distal ACA aneurysms. Patients
harboring ICH of over 3 cm diameter in poor grades should also be carefully treated. 相似文献
99.
Total parenteral nutrition-associated intrahepatic cholestasis in infants: 25 years' experience 总被引:10,自引:0,他引:10
Kubota A Yonekura T Hoki M Oyanagi H Kawahara H Yagi M Imura K Iiboshi Y Wasa K Kamata S Okada A 《Journal of pediatric surgery》2000,35(7):1049-1051
BACKGROUND/PURPOSE: There are few long-term chronological reviews examining the incidence of total parenteral nutrition (TPN)-associated intrahepatic cholestasis (TPNAC) in infants. The authors therefore reviewed TPNAC in their 25-year series, and also looked at the current problems associated with TPN in infants. METHODS: Two hundred seventy-three surgical neonates who received TPN for more than 2 weeks were divided into 3 groups chronologically: group A (1971 through 1982, n = 77), group B (1983 through 1987, n = 72), and group C (1992 through 1996, n = 124). TPNAC was defined as serum direct bilirubin (DB) level greater than 2.0 mg/dL during the neonatal period. RESULTS: The incidence of TPNAC in groups A, B and C was 57%, 31%, and 25% (P< .01), respectively, and the mortality rate from TPN-associated complications was 13%, 3%, and 3% (P< .05), respectively. Over the last 5 years, severe TPNAC developed in 20 patients (16%). Four of 20 died of TPN-associated sepsis with hepatic failure; 2 had hypoganglionosis with intractable stagnant enteritis and subsequent sepsis, and 2 had fatal respiratory or cardiac disease. CONCLUSIONS: The incidence of TPNAC in surgical neonates and TPN-associated mortality rates have decreased significantly. The mortality rate, however, still remains at 3%. Two of 4 fatal cases had hypoganglionosis, which were totally dependent on TPN. In patients who require long-term TPN, TPN still has unsolved problems, and small bowel transplantation may be indicated. 相似文献
100.
Measurement of serum hyaluronic acid as a sensitive marker of liver fibrosis in biliary atresia 总被引:4,自引:0,他引:4
Hasegawa T Sasaki Kimura T Hoki M Okada A Mushiake S Yagi M Imura K 《Journal of pediatric surgery》2000,35(11):1643-1646
PURPOSE: The aim of this study was to clarify whether serum hyaluronic acid level (SHA) can reflect the degree of liver fibrosis in biliary atresia (BA). METHODS: SHA was measured in 44 postoperative BA patients at 7 months to 22 years of age, with sandwich enzyme method (Hy-A 100 kit). SHA was compared with T.Bil (group 1, T Bil < 2; group 2, 2 < or = T Bil < 5; group 3, T Bil > or = 5 mg/dL), fibrosis score (0-6, the number of abnormal values among Alb, PT, ChE, T Chol, Fischer's ratio, prealbumin), and histologic grading (0-IV). RESULTS: SHA was 499.8 +/- 332.5 in group 3, significantly higher than in the control, group 1, or group 2. As fibrosis score rose, SHA became higher, and SHA in Score 6 (430.1 +/- 366.1 ng/mL) and score-5 (172.9 +/- 141.8 ng/mL) was significantly higher than in the control and other scores, respectively. As the histologic grade rose, SHA became higher, and SHA in grade IV (444.8 +/- 323.5 ng/mL) and grade III (166.0 +/- 70.3 ng/mL) was significantly higher than in the control or other Grades. Serial change of SHA since before HPE was parallel to the clinical course in 8 patients. CONCLUSION: SHA may be a useful serum marker reflecting the degree of liver fibrosis in BA. 相似文献