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51.
To assess the biventricular response of the clearance rate of carbon-11 acetate as an index of myocardial oxidative metabolism to increase in work-load, dynamic positron emission tomography was performed at rest and during dobutamine infusion in 14 normal subjects. The clearance rate constant (Kmono) of the left ventricular (LV) myocardium increased during dobutamine infusion (0.112±0.020 min–1 vs 0.065±0.015 min–1 at rest) (P<0.001) in proportion to the increase in the pressure-rate product. Kmono in the right ventricular (RV) myocardium also increased (0.080±0.018 min–1 vs 0.034±0.013 min–1 at rest) (P<0.001), with an excellent correlation with the LV Kmono (r=0.920). The fact that the increase in RV Kmono during dobutamine infusion was greater (158%±81%) than that in LV Kmono (79%±39%) (P < 0.005) indicates a greater increase in oxidative metabolism in the RV in response to inotropic stimulation in normal subjects. Correspondence to: N. Tamaki  相似文献   
52.
In order to reassess the value of quantitative thallium-201 brain SPECT in the differentiation of miscellaneous brain tumors, we studied a total of 89 patients—35 pre-operative patients suspected of having a brain tumor and 54 post-operative patients with a brain tumor. We came to the conclusion that quantitative Tl-201 brain SPECT was very useful in discriminating cerebral radiation necrosis from recurrent tumor, estimating residual tumor burden, and detecting tumor regrowth earlier in postoperative patients. In preoperative patients, however, Tl-201 SPECT cannot be used effectively to differentiate glioma from other intracranial tumors, although intense uptake of Tl-201 may provide evidence of glioblastoma or a hypervascular lesion.  相似文献   
53.
 We investigated the relative contribution of lean body mass (LBM) and body fat mass to bone mineral density (BMD) in 93 healthy Japanese male volunteers (mean age, 33.1 ± 6.9 years; range, 18–54 years). Age, height (Ht), weight (Wt), and body mass index (BMI, Wt/Ht2) were recorded. Body fat mass, percentage of body fat, body fat mass/Ht2, LBM, LBM/Wt, LBM/Ht2, and lumbar spine (L2–L4) and total body BMD (TBBMD) were measured by dual-energy X-ray absorptiometry. On the Pearson correlation test, LBM was positively correlated with L2–L4 BMD. LBM, LBM/Wt, and LBM/Ht2 were positively correlated with TBBMD. However, body fat mass and body fat mass/Ht2 were not correlated with lumbar spine and total body BMD. On the partial correlation test, LBM was still correlated with lumbar spine (r = 0.307, P < 0.05) and total body BMD (r = 0.545, P < 0.0001), irrespective of age and height, whereas body fat mass was not correlated with BMD of these sites (r = −0.069 and −0.169, respectively). We concluded that, in males, LBM is one of the significant determinants of BMD whereas body fat mass is a negligible BMD determinant. Received: February 15, 2002 / Accepted: July 5, 2002 Offprint requests to: T. Douchi  相似文献   
54.
A 39-year-old woman with multiple sclerosis (MS) at exacerbation stage underwent dilatation and curettage. MS is characterized by chronic inflammation, demyelination, and gliosis in the central nervous system. Surgical stress often induces exacerbation of MS symptoms. Therefore, deep anesthesia is required for anesthetic management in cases of MS. We monitored electroencephalograph (EEG), spectral edge frequency 90 (SEF 90), spectral median frequency (SMF) and delta-amplitude for depth of anesthesia using pEEG (Dr?ger, Germany). In this case, anesthesia was induced with sevoflurane and gradually increased to 5% in oxygen 4 l.min-1 and maintained with sevoflurane 2-3% in 2 nitrous oxide l.min-1 and 2 l.min-1 oxygen. Surgery was completed and no spike wave was observed by pEEG monitoring during surgery. In conclusion, sevoflurane anesthesia was useful for a patient with MS during exacerbation stage.  相似文献   
55.
The purpose of this study was to investigate the pharmacological advantages of transarterial chemoembolization (TACE) with cisplatin powder for hypervascular hepatic tumors in animal experiments. VX2 tumors were transplanted to the livers of nine rabbits. Cisplatin (1 mg/kg) was infused into the proper hepatic artery. In the cisplatin-HAI group, cisplatin solution was infused. In the cisplatin-GS-TACE group, after infusion of cisplatin solution, gelatin sponge particles were used for embolization. In the cisplatin-Lp-TACE group, after infusion of a cisplatin powder and lipiodol (10 mg/ml) suspension, gelatin sponge particles were used for embolization. Before and after administration, platinum concentrations in plasma were measured. Using liver specimens that were excised 60 min after infusion, platinum concentrations in tumorous and nontumorous liver tissues were measured. The mean platinum concentration in tumorous tissue was 0.88 μg/ml for the cisplatin-HAI group, 1.23 μg/ml for the cisplatin-GS-TACE group, and 12.65 μg/ml for the cisplatin-Lp-TACE group. The platinum concentration for the cisplatin-Lp-TACE group was significantly higher than that for the cisplatin-HAI group (p = 0.004) and the cisplatin-GS-TAE group (p = 0.004). The mean platinum concentration in nontumorous liver tissue was 0.98 μg/ml for the cisplatin-HAI group, 1.13 μg/ml for the cisplatin-GS-TACE group, and 1.09 μg/ml for the cisplatin-Lp-TACE group; no significant differences were seen. At both 5 and 10 min after infusion, the platinum concentrations for the cisplatin-Lp-TACE group were lower than those for the other two groups. The present results suggest that TACE using cisplatin powder/lipiodol suspension and gelatin sponge for hypervascular hepatic tumors has a number of pharmacological advantages. This material was presented at 2007 CIRSE.  相似文献   
56.
Okada S  Shikata K  Matsuda M  Ogawa D  Usui H  Kido Y  Nagase R  Wada J  Shikata Y  Makino H 《Diabetes》2003,52(10):2586-2593
Diabetic nephropathy is a leading cause of end-stage renal failure. Several mechanisms, including activation of protein kinase C, advanced glycation end products, and overexpression of transforming growth factor (TGF)-beta, are believed to be involved in the pathogenesis of diabetic nephropathy. However, the significance of inflammatory processes in the pathogenesis of diabetic microvascular complications is poorly understood. Accumulation of macrophages and overexpression of leukocyte adhesion molecules and chemokines are prominent in diabetic human kidney tissues. We previously demonstrated that intercellular adhesion molecule (ICAM)-1 mediates macrophage infiltration into the diabetic kidney. In the present study, to investigate the role of ICAM-1 in diabetic nephropathy, we induced diabetes in ICAM-1-deficient (ICAM-1(-/-)) mice and ICAM-1(+/+) mice with streptozotocin and examined the renal pathology over a period of 6 months. The infiltration of macrophages was markedly suppressed in diabetic ICAM-1(-/-) mice compared with that of ICAM-1(+/+) mice. Urinary albumin excretion, glomerular hypertrophy, and mesangial matrix expansion were significantly lower in diabetic ICAM-1(-/-) mice than in diabetic ICAM-1(+/+) mice. Moreover, expressions of TGF-beta and type IV collagen in glomeruli were also suppressed in diabetic ICAM-1(-/-) mice. These results suggest that ICAM-1 is critically involved in the pathogenesis of diabetic nephropathy.  相似文献   
57.
The mineral component of bone is mainly composed of calcium phosphate, constituting 70% of total bone mass almost entirely in the form of hydroxyapatite (HAp) crystals. HAp crystals have a hexagonal system and uniaxial elastic anisotropy. The objective of this study was to investigate the effect of HAp crystallite preference on macroscopic elasticity. Ultrasonic longitudinal wave velocity and the orientation of HAp crystallites in bovine cortical bone are discussed, considering microstructure, density, and bone mineral density (BMD). Eighty cube samples of cortical bone were made from two bovine femurs. The orientation of HAp crystallites was evaluated by integrated intensity ratio of (0002) peak using an X-ray diffractometer. Ultrasonic longitudinal wave velocity was investigated with a conventional pulse system. The intensity ratio of HAp crystallites and velocity were measured in three orthogonal directions; most HAp crystallites aligned in the axial direction of the femurs. Our results demonstrate a linear correlation between velocity and intensity ratio in the axial direction. Significant correlation between velocity and BMD values was observed; however, the correlation disappeared if we focused on the identical type of microstructure. In conclusion, differences in microstructure type have an impact on density and BMD, which clearly affects the velocity. In addition, at the nanoscopic level, HAp crystallites aligned in the axial direction also affected the velocity and anisotropy.  相似文献   
58.
Background  Sentinel nodes (SNs) are the lymph nodes that directly receive lymphatic flow from a primary cancer lesion. The SN concept implies that lymphatic metastasis initially occurs at SNs. SN navigation surgery can be introduced for cancers in which the SN concept is established. In SN navigation surgery, lymph node dissection beyond SNs can be omitted if SNs are metastasis free. Although the SN concept has been investigated frequently for oral and oropharyngeal cancer, it has so far been investigated less for laryngeal and hypopharyngeal cancer. In this study, we investigated whether the SN concept is applicable for laryngeal and hypopharyngeal cancer. Methods  Twenty patients with T2–T4 and clinically N0 laryngeal and hypopharyngeal cancer were recruited. 99mTc-phytate was injected into several sites surrounding the tumor on the day before surgery. Lymphoscintigrams were acquired from at least two different viewpoints. SNs were surveyed intraoperatively, and neck dissections including at least levels II, III, and IV were performed. Results  SNs had occult metastases in five cases. In the remaining 15 cases, neither SNs nor other lymph nodes contained metastases, consistent with the SN concept. There was one false-negative case showing delayed nodal metastasis 2 years after initial surgery. The overall accuracy of the SN concept was 95%. Conclusion  Our study shows that SN biopsy is a reliable strategy to determine correct lymph node status in N0 laryngeal and hypopharyngeal cancer. SN detection was valuable in evaluating the need for neck dissection, whether ipsilaterally or bilaterally. Presented at the 2004 Annual Meeting of the American Academy of Otolaryngology, New York.  相似文献   
59.
Intravesical Bacillus Calmette-Guerin (BCG) therapy is commonly used against superficial urothelial carcinoma, especially carcinoma in situ (CIS). We report a case of tuberculous epididymitis that occurred during a course of intravesical BCG therapy. A 76-year-old man had received intravesical BCG therapy for multiple superficial bladder cancer and CIS in prostatic urethra after transurethral resection of bladder tumor (TUR-Bt). He recognized hard nodules in the left scrotum after 4 times intravesical BCG therapy. Skin fistula in scrotum occurred 5 months later. We performed left orchiectomy with scrotum skin resection. Histological diagnosis was tuberculous epididymitis. Postoperatively, he was administered chemotherapy consisting of isoniazid, refampin and ethambutol.  相似文献   
60.
Adipose tissue-derived stem cells (ASCs) are expected to have clinical applications as well as other stem cells, because ASCs can be obtained safely from adult donors and used in autologous therapies without concern about rejection and the need for immunosuppression. However, the use of gene transfer with Sendai virus (SeV) vectors, which can efficiently introduce foreign genes without toxicity into several cells, with ASCs has not yet been investigated. This study documents on the use of SeV vectors for gene transfer to ASCs. The dose-dependent GFP expression of ASCs transfected with SeV vectors after 48 h of culture at 37 degrees C was first evaluated. Next, the cellular toxicity of ASCs transfected with SeV vectors was verified. In addition, SeV vectors were compared with adenovirus (AdV) vectors. Finally, the time-dependent GFP expression of ASCs transfected with SeV vectors was evaluated. The results showed that transfection of ASCs with SeV vectors results in more efficient expression of transgene (GFP expression) in the ASCs than with AdV vectors after 48 h of culture at 37 degrees C. Moreover, while the transfection of ASCs with AdV vectors at high MOIs was cytotoxic (a lot of transfected cells died) that of ASCs with SeV vectors at high MOIs was not necessarily cytotoxic. In addition, the preservation of multilineage ASCs transfected with SeV was observed. In conclusion, this is the first report describing the successful use of SeV-mediated gene transfer in ASCs, and the results indicate that SeV may thus provide advantages with respect to safety issues in gene therapy.  相似文献   
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