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61.
In view of the high binding ability of cardiac glycosides to the myocardial Na,K-ATPase, radioiodinated digoxin derivatives were surveyed as candidates for myocardial imaging, with particular emphasis on the noninvasive monitoring of cardiac glycoside therapy. Among the radioiodinated digoxin derivatives surveyed, 125I-digoxin-iodohistamine(bis(O-carboxymethyloxime)) showed the highest accumulation in the myocardium and similar binding ability to Na,K-ATPase as digoxin itself against ouabain displacement, as indicated by in vivo and in vitro studies. Based on these results, 123I labeling of digoxin-histamine(bis(O-carboxymethyloxime)) and imaging in a dog demonstrated uptake in the myocardium.  相似文献   
62.
Amygdaloid-kindled rats received intravenous human copper-zinc superoxide dismutase (CuZn-SOD) either in free form or entrapped within liposomes (SOD-L), at 5, 10 or 20 mg/kg. The animals were stimulated at the generalized seizure-triggering threshold 5 min, 2 h and then every 24 h after the drug was given, until 5 consecutive stage 5 seizures were induced. Free CuZn-SOD had little or no effect. However, SOD-L, particularly at 10 mg/kg, had a prolonged anticonvulsant effect, although there was great individual variation in the onset and duration of seizure suppression. This effect of SOD-L may be due to the ability of liposomes to act as a depot for the sustained release of drugs.  相似文献   
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OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected.  相似文献   
67.
A 31-year-old adult with an aortico-left ventricular tunnel (ALVT) arising from the right aortic sinus is reported. Preoperative transesophageal echocardiography demonstrated a ruptured sinus of Valsalva with severe aortic valve regurgitation which originated from the right coronary sinus entering the outlet portion of the left ventricular outflow tract. Operation revealed the aortic entrance of the tunnel was above the right coronary sinus. Direct closure of the orifice of the tunnel using three stitches of 4-0 polypropylene with felt and aortic valve replacement (AVR) was performed. At 10-month follow-up the patient is asymptomatic and receiving no oral medications except anticoagulants. We believe this to be the oldest case of ALVT managed with AVR.  相似文献   
68.
A case of a cervical cancer in a 40-year-old woman with a plasma carcinoembryonic antigen (CEA) level of 29.4 ng/ml was investigated using light and electron microscopy. In addition, the plasma CEA levels before treatment were determined in 168 patients with cervical cancer and in 33 patients with endometrial cancer. CEA was found to be elevated in the plasma of 19% of those with cervical cancer and in 6% of those with endometrial cancer. Effective serial plasma CEA determinations following therapy, in patients whose plasma or tumors initially contain elevated amounts of antigen, might be useful as an adjunctive method in the earlier detection of a recurrent cancer.  相似文献   
69.
Abstract: Monoamine and their acid metabolites were determined in the CSF of 18 drug-treated chronic schizophrenic patients with the symptoms of tardive dyskinesia and neuroleptic-induced Parkinsonism (Parkinsonism). Six healthy volunteers were used as the control group.
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism.  相似文献   
70.
Summary Cell kinetic study plays an important role in treatment planning of brain tumour patients. MIB-1 antibody has recently become available, which detects Ki-67 antigen even in the formalin-fixed paraffin-embedded specimens. We performed MIB-1 immunostaining in 50 meningiomas and 50 neurinomas, and estimated the cell cycle time (tc) and potential doubling time (Tpot) from MIB-1 staining index (MIB-1 SI) and mitotic index (MI). MIB-1 SI logarithmically correlated with MI in both meningiomas and neurinomas. The tc and the Tpot were expressed as a function of the mitosis time (tm), while the tm is known to be around one hour and not exceeding two hours. When the tm was assumed to be one hour, the average tcs of meningiomas and neurinomas were 6.53±3.56 days and 7.67±3.27 days, respectively. The Tpots were447 × (MIB-1 SI)–1.29 × tm in meningiomas, and490 × (MIB-1 SI) –0.98 × tm in neurinomas.The tumour doubling times (Tds) were calculated from serial imaging studies in 22 neurinomas and 15 meningiomas. The Tds were formulated as794 × (MIB-1 SI) –0.83 in meningiomas and1380 × (MIB-1 SI) –0.97 in neurinomas. Most of the Tds correlated well with the Tpots in meningiomas and neurinomas, and exceeded values of the Tpot when the tm is assumed to be one hour, although a few tumours showed unexpectedly longer Tds. The Tpot and the tc estimated from MIB-1 SI and MI are clinically useful parameters for predicting the growth potential of meningiomas and neurinomas where no other simple methods are available.  相似文献   
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