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41.
Experimental delayed cerebral vasospasm was produced in canine basilar arteries by 2 successive injections, 2 days apart, of fresh autogenous arterial blood into the cisterna magna. When angiographic evidence of delayed vasospasm was confirmed 7 days after the initial intracisternal blood injection, a selective inhibitor of 5-lipoxygenase, 2-(12-hydroxydodeca-5,10-diynyl)-3,5,6-trimethyl-1,4-benzoqu inone (AA-861), was infused intravenously at 6.5 X 10(-4) mg/kg/min for 2 hours. However, angiographic evidence of delayed vasospasm was not reversed, and mean regional cerebral blood flow was not significantly increased. In other studies, oral doses of AA-861 at 100 mg/kg/day were given twice a day for 7 days after the initial intracisternal blood injection. In the treated group, angiographic evidence of delayed vasospasm was significantly reduced, and the contractile property of excised basilar arteries in response to vasoconstrictor agents was significantly improved. It is suggested that leukotrienes, 5-lipoxygenase products of arachidonic acid, might be important etiologic factors responsible for the development of delayed vasospasm and that AA-861 would have a therapeutic effect not on the reduction of delayed vasospasm once developed but on the prevention of the development of delayed vasospasm. 相似文献
42.
K Yamashita K Shigematsu T Maeda Y Ishida M Niwa M Ozaki 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1989,93(1):7-15
The antihypertensive effect of bopindolol, a long-acting beta-adrenoceptor blocking agent, was investigated in stroke-prone spontaneously hypertensive rats (SHRSP). One group received tap water during the period of 8 to 32 weeks of age. The average dose of bopindolol administered was calculated from water intake to be approximately 1.4 mg/kg/day. The lowering effect in blood pressure of bopindolol was apparent at the age of 14 weeks, and this continued up to the end of the experiment. Bopindolol significantly reduced the heart rate. Plasma levels of urea nitrogen (BUN), triglyceride, and phospholipid of SHRSP treated with bopindolol were lower than those of the control SHRSP. One of the 8 control SHRSP died, and no rats treated with bopindolol died during the experiment. The histopathological study revealed that three of the control SHRSP had cerebral apoplexy, whereas there was no evidence of cerebral apoplexy in the treated SHRSP. Chronic treatment of bopindolol clearly alleviated myocardial fibrosis and hypertrophic changes in the left ventricular wall of the heart. Decreases in the incidence of proliferative arteritis and malignant nephrosclerosis in the kidney and necrotizing arteritis of the mesenteric arteries were observed in SHRSP treated with bopindolol. The data presented indicate that bopindolol is a powerful antihypertensive agent. 相似文献
43.
O Maeda K Yokokawa T Oka M Namiki H Fujioka M Matsuda M Nishiyama R Shirakura H Hirose T Sonoda 《Urologia internationalis》1986,41(4):318-320
A rare case of a thrombus in the inferior vena cava (IVC) after retroperitoneal lymphadenectomy for a testicular tumor is reported. A computed tomograph performed after the operation incidentally showed a filling defect in the IVC. However, it was impossible to decide whether the defect was due to an ordinary or a neoplastic thrombus. For this reason, a thrombectomy was performed, and postoperatively it was diagnosed as an ordinary thrombus. The cause of thrombi found only in the IVC is reviewed and the indication for thrombectomy is discussed. 相似文献
44.
R. P. Iacono M. D. F.A.C.S. J. D. Carlson S. M. Kuniyoshi Y. J. Li A. S. Mohamed G. Maeda 《Acta neurochirurgica》1997,139(5):433-441
Summary The current interest in stereotactic posteroventral pallidotomy (PVP) for treating Parkinson's disease and the variability of published results have raised questions regarding techniques for target localization. In our technique the probe is guided to the optimum target at the most ventral pallidum and ansa lenticularis by macroelectrode stimulation of the internal capsule and optic tract from within the globus pallidus, with the thresholds providing a relative measure of the electrode proximity to these structures. We have characterized these localizing macroelectrode stimulation parameters in 57 posteroventral pallidotomies with consistent anatomic lesion placement, excellent outcome, and no complications.Using a 1.8 × 2.0 mm radiofrequency electrode for macroelectrode stimulation (RFG-3C, Radionics Inc.), minimum voltages (thresholds) to activate motor (at a frequency of 2 Hz) or visual (at a frequency of 100 Hz) responses as well as impedance measurements were obtained at the final target (Tf) and at distances proximal to Tf along the electrode trajectory. The visual and motor threshold voltages at Tf via our standard approach angles (50 ° above base plane, 20 ° from the sagittal plane), had a range of 1.0 to 1.5 V, and 2.0 to 3.5 V respectively. We also found that as the probe approaches Tf there is a significant decrease in voltage thresholds for motor (P<.0001) and visual (P<.0001) responses in an individual patient indicating that the probe is converging on these structures. Increases in impedance between Tf, 2–3 mm, and 4–5 mm proximal to Tf were also statistically significant (P<.0001). Microelectrode recording of electrophysiological neuronal activity at various points along the trajectory towards the target showed distinct firing patters providing identification of the globus pallidus externus and internus, ansa lenticularis, and optic tract.Macroelectrode electrophysiological stimulation within the target volume, inducing threshold responses in the internal capsule and optic tract, provides for accurate localization of the most effective PVP target in the ansa lenticularis. In unresponsive patients, the utilization of microelectrode recording for the identification of the pallidal borders and the optic tract improves safety. 相似文献
45.
Takuo Fujita Masaaki Fukase Takao Shimada Hironosuke Yamamoto 《Journal of bone and mineral metabolism》1992,10(1):37-40
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin
D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess
the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at
higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups
with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications
for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a
week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3.
In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body
T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior
or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below
0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio
values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of
vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis. 相似文献
46.
Comparison of p53 expression in proximal and distal gastric cancer: Histopathologic correlation and prognostic significance 总被引:2,自引:0,他引:2
Huihuan Tang MD Shuichi Hokita MD PhD Xiangming Che MD Masamichi Baba MD PhD Kuniaki Aridome MD PhD Fumio Kijima MD Gen Tanabe MD PhD Sonshin Takao MD PhD Dr. Takashi Aikou MD PhD 《Annals of surgical oncology》1997,4(6):470-474
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but
no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53
expression of proximal and distal gastric cancer concerning histopathology and prognosis.
Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical
methods.
Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher
than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference
between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology
of gastric cancer.
Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer. 相似文献
47.
48.
Changes in cardiac myosin heavy chain (MHC) gene expression and isozyme transitions have been shown to be caused by developmental changes, hemodynamic overload, or the activity of various hormones. In this study, to examine whether caffeine, which has teratogenic effects on the fetal cardiovascular system, causes the distribution of cardiac MHC phenotype and, if so, to evaluate the mechanisms of the distribution of cardiac MHC phenotype by caffeine, we examined the effects of caffeine, theophylline, and cAMP on the cardiac MHC isoform transitions at the gene and protein levels using hypothyroid adult rats. Furthermore, we examined the expression of alpha- and beta-MHC gene in cardiac muscles of fetuses whose dams had received caffeine. The results showed that caffeine, theophylline, and cAMP caused accumulations of alpha-MHC mRNA and MHC isozyme V1. Furthermore, in the fetal hearts, it was recognized that caffeine induced an accumulation of alpha-MHC gene expression, as was also seen in the dams. However, this effect of caffeine on the heart was stronger in the fetus than in the dam. Intracellular cAMP concentration was increased by the administration of caffeine, theophylline, or cAMP, and the levels showed a positive correlation with those of alpha-MHC mRNA. These results suggest that the induction of alpha-MHC mRNA expression by the administration of caffeine may be induced by an increase in intracellular cAMP concentration. 相似文献
49.
The present investigation was designed to clarify what induces circulatory enhancement in the delay procedure. Two different sizes of a bipedicle flap were prepared in rats and the blood flow was measured at the centre of the flaps. The delay effect, that is, elongation of the survival length, was significantly less in the wide flap than in the narrow flap, though the two flap groups had almost identical levels of central ischaemia when averaged for each group. On the basis of ischaemic level, the flaps, regardless of size, were classified into two groups: more and less ischaemic than the mean. The delay effects noted in the more ischaemic flaps were not significantly different from those in the less ischaemic flaps. These results indicate that flap width has more influence on the delay effect than the degree of ischaemia. 相似文献
50.
Yamaji Yasuyoshi; Nakazato Yuichi; Oshima Naoki; Hayashi Matsuhiko; Saruta Takao 《Nephrology, dialysis, transplantation》2004,19(10):2592-2597
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients. 相似文献