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Effects of intraaortic balloon position on renal artery blood flow.   总被引:2,自引:0,他引:2  
Debate continues over what happens to renal blood flow when intraaortic balloons are adjacent to the renal arteries. Fourteen dogs were prepared by implanting instruments to measure heart rate; right atrial, pulmonary arterial, carotid arterial, and femoral arterial pressures; cardiac index; mixed venous oxygen saturation; urine output; and left and right renal blood flows. A 12-mL intraaortic balloon was inserted through the left (n = 9) or right (n = 5) femoral artery. The position of the balloon was randomized so that it was initially placed in either the control (thoracic) or renal position (at the level of the renal arteries). Intraaortic balloon pumping was performed for 4 hours in each position. In 8 dogs, at least one of the renal arteries had partial occlusion, 23% to 98% decrease in flow (mean decrease, 66%), while the intraaortic balloon was in the renal position. An intraaortic balloon in the renal position results in lower renal blood flow as well as a high risk (57%) of selective renal artery occlusion. Decreased renal blood flow is not apparent using conventional monitoring, as hemodynamics do not change.  相似文献   
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OBJECTIVE: Our treatment strategy for pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries is a staged repair that comprises the first complete unifocalization (UF) with 'unification' of intrapulmonary arteries and then the definitive repair. The purpose of this study is to evaluate the outcome of our staged repair strategy with complete UF and to determine the results of our current management strategy. METHODS: From 1982 to 2004, 113 consecutive patients were treated with staged repair at our institute. We evaluated the risk of definitive repair failure or death in the 3 years after definitive repair using logistic regression. Furthermore, we compared the early group (patients who underwent UF before December 1995) and the late group (patients who underwent UF after January 1996). RESULTS: The mean follow-up interval was 8.8 years (0.8 months to 23.3 years), and Kaplan-Meier-estimated overall survival rates after first UF were 80.9, 73.8, and 69.9% at 5, 10, and 15 years, respectively. Survival in patients with an absent central pulmonary artery (PA) was significantly lower than in those with a central PA (p<0.05), and the factor that was significantly associated with definitive repair failure or death in the 3 years after definitive repair was central PA morphology (p<0.05). Higher mean PA pressure after UF was detected in patients with hypoplastic central PA, compared with those without hypoplastic PA (30.9 mmHg vs 23.3 mmHg, p<0.05). In the late group, age (in years) at first UF (3.9 vs 8.4, p<0.01), second UF (4.3 vs 9.2, p<0.01), and definitive repair (5.8 vs 9.1, p<0.01) was significantly younger than in early group, and the survival rate after first UF in the late group was 96.2 and 91.3% at 3 and 7 years, respectively. Systolic right ventricular pressure and the pressure ratio between the right and the left ventricles after definitive repair in the late group were significantly lower than in the early group (53.6 mmHg vs 75.0 mmHg, p<0.01; 61.7% vs 75.9%, p<0.05). CONCLUSIONS: Hypoplastic central PA was a significant risk factor in this disease. The overall survival was improved by our current management strategy. Improved RV pressure after definitive repair appears to affect the long-term outcome.  相似文献   
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Pulmonary thromboembolism induced by deep vein thrombosis (DVT), which is known as economy-class syndrome, is one of sudden death in psychiatric patients under physical restraint. (1) A decrease in venous blood flow, (2) damage to vessel walls, and (3) the enhancement of blood clotting are the major risk factors for DVT (Virchow triad). It has been speculated that physical restraint inhibits venous blood flow, and that antipsychotic drugs facilitate blood clotting. In order to prevent sudden death due to DVT, prophylactic measures and early diagnosis are crucial. Whereas Doppler ultrasonography and contrast venography are the gold standards for the diagnosis of DVT, more simplified methods are now under development. Of those, D-dimer measurement, which can be conducted with a small blood sample, is the most potent candidate for the biochemical diagnosis of DVT. Although there are many prophylactic measures, including anticoagulant medications and physical therapies, it is not clear which is the most effective and suitable in psychiatric practice. Psychiatric professionals should pay closer attention to DVT in psychiatric patients under physical restraint.  相似文献   
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We retrospectively reviewed 32 patients who underwent parathyroidectomy at our hospital for the last fourteen years. 1) Clinical appearance of primary hyperparathyroidism was in younger age in women. 2) In previous history or at the time of PTX, 9 patients had malignant tumors including 6 thyroid cancers, 36% of the patients with out bone related symptoms had a remarkable decrease in bone mineral content. 3) After PTX, none of patients had recurrent urolithiasis and bone mineral content of all patients was significantly increased in a short time. In addition, upper GI complaints were improved, or hypertension was partially normalized. However, renal insufficiency remained unchanged. 4) In preoperative localization study, Ultrasound sonography (US) demonstrated the best accuracy rate of 88% when only one gland was involved. US was able to detect multiple gland involvement only in 20% of 5 cases. 5) Hypercalciuria was recognized as one of the risk factors of stone formation in patients with primary hyperparathyroidism.  相似文献   
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Enhancement of the antitumor effects of adriamycin (ADR) by concomitant use of degradable starch microspheres (DSM) and pharmacokinetics of ADR in combination with DSM was investigated. An intra-arterial chemotherapy model of the nude rats transplanted of human gastric cancer xenografts (H-154) in the hind-limbs was used for this study. Drug was administered through a catheter inserted into the carotid artery with the tip in the common iliac artery. In the pharmacological study, increase of regional uptake of ADR and decrease of systemic distribution of ADR were recognized in some degree. DSM 30 mg/kg, which caused temporary arrest of blood flow in the tumor, had an only weak effect on tumor growth. ADR 3 mg/kg mixed with DSM 30 mg/kg was more effective than ADR 3 mg/kg solution. Furthermore, mixture of ADR 2 mg/kg and DSM 30 mg/kg had a greater effect on tumor growth than ADR 2 mg/kg following DSM 30 mg/kg. It seems that embolization by DSM, retention of ADR in regional tissues and cytotoxic effect of ADR have contributed to such a strong effect of ADR mixed with DSM.  相似文献   
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Rat peritoneal macrophages, which were induced by intraperitoneal injection of vitamin E for 6 successive days, contained 387.6 to 569.0 ng alpha-tocopherol/10(6) cells and produced 0.9 to 1.5 nmol O2-/min/10(6) cells following stimulation by phorbol myristate acetate (PMA). On the other hand, control macrophages contained 1.7 ng alpha-tocopherol/10(6) cells and produced 3.9 to 4.5 nmol O2-/min/10(6) cells. The particulate fraction of macrophages from vitamin E-treated rats contained 285.2 to 294.4 ng alpha-tocopherol/10(6) cells and showed scarcely any protein kinase C activity, whereas the specific activity of control rats showed 323 to 357 pmol/min/mg protein. From these results, we concluded that vitamin E seems to decrease O2- production from macrophages stimulated with PMA through inhibition of protein kinase C.  相似文献   
30.
Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1). Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases. Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis, immunoexpression of differentiation markers was examined. Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every NF1 case.  相似文献   
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