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51.
1. The inducible isoform of nitric oxide synthase (iNOS) is expressed in human and experimental cardiac allografts and is localized to infiltrating macrophages, cardiac myocytes, endothelial cells and smooth muscle cells. A recent clinical report proposes a causal link between myocardial expression of iNOS and ventricular contractile dysfunction, a potentially graft- and life-threatening post-transplant complication. 2. Coronary blood flow is elevated in human graft recipients with biopsy proven cellular rejection, indicating that vasodilation accompanies graft rejection. In Lewis-to-F-344 coronary resistance vessels, which show intimal expression of iNOS, pressure-induced myogenic tone is significantly inhibited. Selective iNOS inhibition partially reverses the inhibition of myogenic tone, confirming that iNOS produces vasoactive nitric oxide (NO) and may mediate the rejection-induced vasodilation seen clinically. 3. Endothelial dysfunction, identified as loss of endothelium-dependent dilation, has tremendous prognostic significance in vascular diseases of multiple aetiologies. In transplantation, endothelial dysfunction predicts early cardiac allograft vasculopathy and poor clinical outcome. Lewis-to-F-344 coronary vessels develop endothelial dysfunction at 1 week post-transplantation, but this is preceded by a transient state of endothelial cell hyperfunction, with enhanced endothelial production of NO. 4. The normal interaction between endothelial and smooth muscle cells in coronary resistance vessels is critical for the regulation of coronary blood flow and the maintenance of fluid homeostasis. With allospecific expression of iNOS, the inhibition of vascular tone predicts greatly enhanced intravascular pressure in precapillary arterioles and capillaries; this would be expected to cause a net movement of fluid from the intravascular compartment into the myocardial interstitium, resulting in ventricular oedema, non-compliance and poor contractile performance.  相似文献   
52.
Stabilized enzymatic reagents for measuring some components in biological fluids have been successfully developed based on two kinds of thermostable enzymes derived from Bacillus stearothermophilus with separation of the reagent into two complementary solutions. The thermostable glucokinase produced was applied to the measurement of glucose and creatine kinase activity, while the alanine dehydrogenase produced was used for the measurement of gamma-glutamyltransferase activity. The enzymatic reagents were also stabilized by developing two separate reagents with an optimum pH for the main reagent components. The stability of the reagents in liquid form was examined at 10 degrees C. It was clearly shown that the reagents for measuring glucose and creatine kinase activity were stable and retained their full capability for accurate measurement in biological fluids for over one year. The alanine dehydrogenase product was stable for at least 40 days.  相似文献   
53.
BACKGROUND: Hepatocellular carcinoma (HCC) occurs in patients with hepatitis C virus-RNA positive chronic liver disease. It is important to prevent HCC with drug administration. METHODS: A retrospective study was undertaken to evaluate the long term preventive effect of Stronger Neo-Minophagen C (SNMC) on HCC development. SNMC is a Japanese medicine that is commonly administered to patients with chronic hepatitis C to improve the serum alanine aminotransferase (ALT) level. Of 453 patients diagnosed with chronic hepatitis C retrospectively in the study hospital between January 1979 and April 1984, 84 patients (Group A) had been treated with SNMC; SNMC was given at a dose of 100 mL daily for 8 weeks, then 2-7 times a week for 2-16 years (median, 10.1 years). Another group of 109 patients (Group B) could not be treated with SNMC or interferon for a long period of time (median, 9.2 years) and were given other herbal medicine (such as vitamin K). The patients were retrospectively monitored, and the cumulative incidence of HCC and risk factors for HCC were examined. RESULTS: The 10th-year rates of cumulative HCC incidence for Groups A and B were 7% and 12%, respectively, and the 15th-year rates were 12% and 25%. By Cox regression analysis, the relative risk of HCC incidence in patients not treated with SNMC (Group B) was 2.49 compared with that of patients treated with SNMC (Group A). CONCLUSIONS: In this study, long term administration of SNMC in the treatment of chronic hepatitis C was effective in preventing liver carcinogenesis.  相似文献   
54.
Macroscopic dynamics of the hydrodynamic (Lamb) impulse J V induced by the chaotic vortex filaments in the counterflowing superfluid turbulent HeII is studied. Both the Lamb impulse and its dynamics are considered on the basis of the Gaussian model of chaotic vortex tangle elaborated earlier by one of the authors (S.N.). The rate of change of the quantity J V is shown to be equal to the force F sn exerted by the normal component on the vortex tangle. That contradicts the obvious fact that in steady case the quantity J V should have a constant value. Resolving that apparent paradox we draw some conclusions concerning the stochastic dynamics of the quantized vortex lines.  相似文献   
55.
To assess the efficacy of the zinostatin derivative, the anti-tumor agent, styrene-maleic acid neocarzinostatin, in treating multiple small liver cancers, 29 patients with multiple hepatocellular carcinoma of 3 cm or less in diameter were treated with intraarterial injections of this high molecular weight agent, mixed with Lipiodol. Computed tomography 3 months after the first therapy showed complete deposition of Lipiodol in the entire area of the original tumor in 8 patients (27.6%), 50%-99% deposition in 4 (13.8%), 10%-49% in 10 (34.5%), and less than 10% in 7 (24.1%). After repeated injections, Lipiodol deposition in the entire area of the original tumor was found in 11 patients (37.9%). The degree of Lipiodol deposition depended on the angiographic vascularity of the tumor and on the images of the computed tomogram during arterial portography. Although complete deposition of Lipiodol was found in all tumors in 10 (58.8%) of the 17 patients with well demarcated round hypervascularity, only 1 (8.3%) of 12 patients with ill demarcated tumors showed complete deposition of Lipiodol in the tumors. Taking into account that hypervascularity on angiograms was closely correlated with the degree of Lipiodol accumulation on computed tomograms taken later, it appears that well demarcated round-shaped liver cancer is the best candidate for styrene-maleic acid neocarzinostatin therapy.  相似文献   
56.
The spin dynamics and the spin relaxation mechanisms of the superfluid3He-B were studied by using the NMR method in a slab geometry, where the superfluid3He-B was confined between narrow parallel plates with a gap smaller than the healing length of then-texture and the magnetic field was applied parallel to the plates. The relaxation parameter in the Leggett-Takagi (LT) equations was determined from a line width measurement of the transverse CW NMR. By using the pulsed NMR method, spin dynamics were studied in the nonlinear region. The observed spin dynamics were in good agreement with a numerical calculation of the LT equations together with the relaxation parameter determined by the CW NMR. When the tipping angle became larger than a certain critical value, the superfluid3He-B entered the Brinkman-Smith (BS) state. In this case, we observed the slow relaxation process in the BS state and then the rapid recovery process from the BS state to the initial non-Leggett configuration. The slow process in the BS state was attributed to the surface relaxation mechanism due to the torque from the surface-field energy.  相似文献   
57.
A prospective randomized trial was conducted to evaluate the efficacy of long-term oral administration of low-dose tegafur combined with uracil as an adjuvant chemotherapy, following transcatheter arterial embolization (TAE) in 40 patients with hepatocellular carcinoma (HCC). Forty eligible patients were randomized into two groups: 20 with TAE plus UFT (a compound of tegafur 200 mg and uracil 448 mg per day) and 20 with TAE alone. A good necrosis rate or decrease in size of more than 70% of the original tumor mass was attained in 10 by TAE plus UFT arm and in 12 by TAE arm alone. As for the "responded" patients, there was no significant difference in the time from tumor response to tumor regrowth between the two groups. The appearance rate of ascites and/or encephalopathy in patients with chemotherapy was slightly higher than that in control patients. The median survival time was 22.7 months for TAE plus UFT arm and 28.2 months for TAE arm alone. There was no significant difference in the cumulative survival curves. In conclusion, these results indicated no substantial benefit for this chemotherapy regimen, as an adjuvant therapy for patients with HCC during repeated TAE.  相似文献   
58.
The oxidation of propylene to propylene oxide (PO) with hydrogen–oxygen mixtures was studied on gold supported on the mesoporous titanium silicate, Ti-TUD. The catalyst gave stable activity at low conversions of propylene (<6%) and high selectivity to PO (>95%). Kinetic data were fit to a power-rate law and gave the following expression: rPO = k(H2)0.54(O2)0.24(C3H6)0.36. The fractional orders in hydrogen, oxygen, and propylene indicated that these reactants interacted with the catalyst to form species that led to the final PO product. The catalyst likely operated by the commonly accepted mechanism of hydrogen peroxide production on gold sites, and epoxidation on titanium centers. Carbon dioxide was formed primarily from further oxidation of PO rather than the oxidation of propylene, while water was produced from the reaction of hydrogen and oxygen.  相似文献   
59.
We numerically study spin turbulence (ST) in spin-1 spinor Bose-Einstein condensates with ferromagnetic and antiferromagnetic interaction by solving the Gross-Pitaevskii equation. In the previous study for ST with ferromagnetic interaction, the directions of the spin density vectors were found to be spatially disordered but temporally frozen. This behavior of ST is similar to that of spin glass. In this study, to characterize the “spin-glass-like” behavior, we calculate the order parameter of the spin glass. In ST with ferromagnetic interaction, we confirm the growth of the order parameter, which indicates that ST behaves like spin glass. On the other hand, in ST with antiferromagnetic interaction, the order parameter does not grow. This means that spin density vectors temporally fluctuate, not being frozen.  相似文献   
60.
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