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991.
992.
We examined the effects of a new inotrope, OPC-8212 (OPC: 2(1H)-quinolinone), on coronary sinus flow (CSF), myocardial oxygen consumption, myocardial lactate extraction ratio (LER), cardiac index (CI) and pulmonary arterial diastolic pressure (PADP) in eleven patients with prior myocardial infarction. Measurements were taken before (control) and 8 hours after administration of OPC (480 mg, p.o.). A cardiac function curve was obtained in each stage with rapid intravenous administration of 500 ml of saline (loaded state) after baseline measurements. There was a significant increase in the cardiac index and decrease in the pulmonary arterial diastolic pressure in the loaded state after OPC. Thus the ventricular function curve was shifted to the left and showed a steep incline, indicating an increased inotropic state. On the other hand, myocardial oxygen consumption and myocardial lactate extraction ratio were unchanged. Thus we concluded that OPC improved cardiac performance without increasing myocardial oxygen consumption.  相似文献   
993.
An osteogenic sarcoma of the tibia occurred in an eight-year-old boy with epidermolysis bullosa dystrophica hereditaria (EBDH) (Hallopeau-Siemens type). The patient had had the congenital skin disease since the time of birth. A painful swelling appeared in the proximal portion of his right tibia, which was diagnosed as osteogenic sarcoma on biopsy study. The patient died of massive pulmonary metastases and cachexia four months after the onset of the tumor. Osteogenic sarcoma in a patient with EBDH seems not to have been previously reported. EBDH has been known to be occasionally associated with squamous cell carcinoma. Whether an impairment of the patient's defense mechanism by the chronic skin disease might have enhanced the rapid progression of the associated bone malignancy is unknown.  相似文献   
994.
Twenty-seven shoulders (in 26 patients) that had surgical repair of a rupture of the long head of the biceps tendon between 1962 and 1981 were evaluated at three to 22 years after injury (mean, 13 years). Thirty similar patients had been treated nonsurgically and were evaluated two to 15 years (mean, 4.6 years) after tendon rupture. Biomechanical testing was performed on ten patients in the surgical group and 13 in the nonsurgical group. Residual arm pain was infrequent in both surgically and nonsurgically treated groups. Residual subjective weakness at the elbow was reported in four of the surgical group and in 20 of the nonsurgical group. Surgically treated patients returned to work later than nonsurgical patients; however, 11 in the nonsurgical group were not able to return to full work capacity, versus only two in the surgical group. On biomechanical testing, the nonsurgical group had lost a mean of 21% of supination strength and 8% of elbow flexion strength but had no weakness in grip, pronation, or elbow extension. The surgical group had lost no strength in any of these testing modes.  相似文献   
995.
996.
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998.
A system was developed for exposure of unanesthetized mice to airborne chemicals and for continuous measurement of their breathing pattern prior to, during and following exposure. By measuring inspiratory and expiratory airflows (VI and VE), and integration with time to yield tidal volume (VT), we obtained characteristic modifications to the normal breathing pattern. These permitted recognition that a specific portion of the respiratory tract was affected by the selected airborne chemicals. Following recognition, we also quantitated the degree of effect using one specific measurement in each case. An effect on the upper respiratory tract, induced by the sensory irritant, 2-chlorobenzylchloride, was quantitated by measuring a decrease in respiratory frequency. An effect on the conducting airways, induced by the airway constrictor, carbamylcholine, was quantitated by a decrease in VE at the mid-point of VT. An effect at the alveolar level, induced either by the vagal nerve ending stimulant, propranolol, or by the pulmonary irritant, machining fluid G, was quantitated by an increase in the length of a pause induced at the end of expiration. The system is easy to construct and operate and can be used to rapidly evaluate the effects of airborne chemicals on the respiratory tract.  相似文献   
999.
The influence of phagocytosis on hepatic energy metabolism was investigated in rats injected with colloidal carbon. Following injection of 6 mg colloidal carbon per 100 g body wt (BW) the hepatic energy charge potential (ECP) remained unchanged. However, oxidative phosphorylation of the isolated mitochondria (PR) increased significantly to 120 and 124% of the control at 1 and 3 hr, respectively, and returned to the normal range at 6 hr. The pyruvate level rose to 195 and 150% at 3 and 6 hr. The lactate level was elevated to 195 and 143% at 3 and 6 hr. Following injection of 20 mg colloidal carbon per 100 g BW, the ECP decreased from 0.865 to 0.783 at 1 hr, but recovered to the normal range thereafter. The PR increased more markedly to 135% at 1 hr, concomitant with an elevation of the ketone body ratio. At 3 hr it remained elevated at 118%, but returned to the normal level at 6 hr. The pyruvate and lactate levels increased to more than 250% at 1 and 3 hr. At 6 hr, the lactate level returned to the control level, but the pyruvate level showed still higher level than the control. These results indicate that phagocytosis exerts an acute metabolic load on the total liver. It was tentatively proposed that parenchymal and nonparenchymal cells in the liver have interrelation in the energy metabolism, and that an enhancement of hepatocellular mitochondrial phosphorylative activity occurs to assist the accelerated metabolism due to phagocytosis.  相似文献   
1000.
Laser thermal angioplasty is a new technique. The longest follow-up is 3 years. It is used increasingly for the treatment of atheromatous disease of the femoropopliteal segment. The authors describe a case of successful recanalization of a completely occluded left external iliac artery using laser thermal angioplasty. The artery was approached through a left femoral dissection. The patient was discharged from the hospital on postoperative day 4 without claudication. The present indications and potential benefits and complications of this procedure are discussed.  相似文献   
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