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11.
PET enables quantitative imaging of the rate constants K 1, k 2, k 3, and k 4, with a reversible two tissue compartment model (2TCM). A new method is proposed for computing all of these rates within a reasonable time, less than 1 min. A set of differential equations for the reversible 2TCM was converted into a single formula consisting of differential and convolution terms. The validity was tested on clinical data with 18F-FLT PET for patients with glioma (n = 39). Parametric images were generated with the formula that was developed. Parametric values were extracted from regions of interest (ROIs) for glioma from the images generated, and they were compared with those obtained with the non-linear fitting method. We performed simulation studies for testing accuracy by generating simulated images, assuming clinically expected ranges of the parametric values. The computation time was about 20 s, and the quality of the images generated was acceptable. The values obtained for K 1 for grade IV tumor were 0.24 ± 0.23 and 0.26 ± 0.25 ml?1 min?1 g?1 for the image-based and ROI-based methods, respectively. The values were 0.21 ± 0.12 and 0.21 ± 0.12 min?1 for k 2, 0.13 ± 0.07 and 0.13 ± 0.07 min?1 for k 3, and 0.052 ± 0.020 and 0.054 ± 0.021 min?1 for k 4. The differences between the methods were not significant. Regression analysis showed correlations of r = 0.94, 0.86, 0.71, and 0.52 for these parameters. Simulation demonstrated that the accuracy was within acceptable ranges, namely, the correlations were r = 0.99, r = 0.97, r = 0.99, and r = 0.91 for K 1, k 2, k 3, and k 4, respectively, between estimated and assumed values. This results suggest that parametric images can be obtained fully within reasonable time, accuracy, and quality.  相似文献   
12.
To assess whether platelets are activated in transient global amnesia (TGA) and TIA, blood samples were analyzed by fluorescence-activated cytoscan using antibodies specific for platelet fibrinogen receptor (PAC1) and P-selectin (CD62P). Samples from TIA contained high levels of CD62P compared with age-matched control subjects, whereas those from TGA did not. The authors suggest that activated platelets are involved in brain ischemia, whereas ischemia appears not to be associated with most TGA.  相似文献   
13.
In the present study we examined the combined effect of application of a capacitively coupled electric field (CCEF) and the tissue respiration stimulating agent, Solcoseryl, on the promotion of bone formation around dental implants histologically and mechanically. After a dental implant was inserted into each femur of Japanese white rabbits, Solcoseryl (2 ml/kg) was administered intravenously in the ear vein and a CCEF was applied for 4 h per day for 14 days. The degree of bone formation on microscopic observation, bone contact ratio, bone surface area ratio, and the level of removal torque of the implant in the Solcoseryl- and CCEF-treated group were significantly higher than the respective value in the control group, which had not been treated with Solcoseryl nor CCEF. Thus, the combination of CCEF stimulation and Solcoseryl effectively promoted the formation of new bone. It is suggested that the clinical use of a combination of CCEF stimulation and Solcoseryl for dental implants promotes osseointegration.  相似文献   
14.
We report the case of a 58-year-old man who underwent complete resection for locally advanced non-small-cell lung cancer (cT4N2M0). The patient received UFT (400 mg/m2 orally on days 1-14 and 22-35) and cisplatin (80 mg/m2 intravenously on days 8, 29) with a total 40 Gy, delivered in 20 fractions on days 1-26. The tumor reduction rate was 76%, and no remarkable toxicities were observed. The patient underwent complete resection and a pathologic complete response was observed. This induction concurrent chemoradiotherapy (followed by surgery) is considered to be effective and safe.  相似文献   
15.
BACKGROUND: The aim of the present study was to investigate whether rapid rewarming after hypothermia therapy during seizures alters the endogenous nitric oxide (NO) production in and around hippocampus, cortical cerebral blood flow (cCBF), and mean arterial blood pressure (MABP) in immature rabbits. METHODS: The hypothermic rabbits (rectal temperatures, 33 degrees C) were given kainic acid (KA; 12 mg/kg, i.v; at 0 min), followed by cooling (33 degrees C) for 60 min (at 60 min), then either rewarming (RW; 33-37 degrees C) was started (KA[+]RW[+] group, n = 7) or cooling was continued (KA[+]RW[-] group, n = 7) for another 60 min (at the end 120 min). In the KA(-)RW(+) group (n = 5), 0.5 mL normal saline was given (at time 0 min), followed by cooling (33 degrees C) for 60 min (at 60 min), then rewarming to 37 degrees C was started with observation for another 60 min (at the end 120 min). NO production in and around hippocampus was continuously measured by an NO-selective electrode, cCBF by laser Doppler flowmetry, cortical electroencephalogram (EEG), rectal and cerebral temperatures, and MABP during the experiment. Comparisons were made of these parameters between the values at 60 min and 120 min after the KA administrations. RESULTS: KA administration induced abnormal discharges in both KA(+)RW(+) and KA(+)RW(-) groups at the same degree. The KA(+)RW(+) group had a significant increase in %NO, and significant decreases in %cCBF and MABP after rapid rewarming, compared with before rewarming. In the KA(+)RW(-) group, there were no significant changes in %NO, %cCBF, and MABP between values at 60 and 120 min. These changes after rapid rewarming in the KA(+)RW(+) group were different from those with only elevation in brain temperature from 33 to 37 degrees C without seizures (KA[-]RW[+] group). CONCLUSIONS: These results suggest that rapid rewarming after hypothermia therapy induces an increase in the NO production in and around hippocampus and the decreases in cCBF and MABP during seizures in immature rabbits.  相似文献   
16.
Thymidine phosphorylase (TP) catalyzes the reversible conversion of thymidine to thymine, thereby generating 2-deoxy-D-ribose-1-phosphate, which upon dephosphorylation forms 2-deoxy-D-ribose (D-dRib), a degradation product of thymidine. We have previously shown that D-dRib promotes angiogenesis and chemotaxis of endothelial cells and also confers resistance to hypoxia-induced apoptosis in some cancer cell lines. 2-Deoxy-L-ribose (L-dRib), a stereoisomer of D-dRib, can inhibit D-dRib anti-apoptotic effects and suppressed the growth of KB cells overexpressing TP (KB/TP cells) transplanted into nude mice. In this study, we examined the ability of L-dRib to suppress metastasis of KB/TP cells using two different models of metastasis. The antimetastatic effect of L-dRib was first investigated in a liver-metastasis model in nude mice inoculated with KB/TP cells. Oral administration of L-dRib for 28 days at a dose of 20 mg/kg/day significantly reduced the number of metastatic nodules in the liver and suppressed angiogenesis and enhanced apoptosis in KB/TP metastatic nodules. Next, we compared the ability of L-dRib and tegafur alone or in combination to decrease the number of metastatic nodules in organs in the abdominal cavity in nude mice receiving s.c. of KB/TP cells into their backs. L-dRib (20 mg/kg/day) was significantly (P < 0.05) more efficient than tegafur (100 mg/kg/day) in decreasing the number of metastatic nodules in organs in the abdominal cavity. By in vitro invasion assay, L-dRib also reduced the number of invading KB/TP cells. L-dRib anti-invasive activity may be mediated by its ability to suppress the enhancing effect of TP and D-dRib on both mRNA and protein expression of vascular endothelial growth factor and interleukin-8 in cultured KB cells. These findings suggest that L-dRib may be useful in a clinical setting for the suppression of metastasis of tumor cells expressing TP.  相似文献   
17.
Two glucuronides (4'-O-, and 7-O-) and a glucuronyl (7-O-) sulfate (4'-O-) of genistein, two glucuronides (4'-O-, and 7-O-) and a glucuronyl (7-O-) sulfate (4'-O-) of daidzein, 7-O-glucuronides of glycitein, dihydrodaidzein and O-desmethylangolensin were isolated from the urine of volunteer subjects fed soy bean curds (Tofu). The estrogenic activities, i.e., i) the effect on the estrogen-dependent growth of MCF-7 cells, ii) the binding ability to human estrogen receptors (hERs) alpha and beta, and iii) the effect on hER-dependent beta-galactosidase induction, of these isoflavone metabolites were examined. Two synthetic isoflavone aglycones (dihydrodaidzein and O-desmethylangolensin) and four synthetic sulfates (4'-O- and 4'-, 7-di-O-) of genistein and daidzein were also studied for their estrogenic activities for the purpose of comparison. With respect to estrogenic acivity, the tested isoflavone metabolites were classified into three groups. The first group shows a very poor stimulatory effect toward the growth of MCF-7 cells, binding activity, and beta-galactosidase induction. The sulfates belong to this group. The second group shows a moderate binding activity but poor stimulation and beta-galactosidase induction. Some glucuronyl conjugates belong to this group. The last group shows a moderate stimulation and beta-galactosidase induction but poor binding activity. A mixed type of conjugates having glucuronyl and sulfony moieties belong to this group.  相似文献   
18.
The aim of this prospective study was to investigate, using echocardiography, the relationship between heart murmurs found in the neonatal period and atrial septal defect (ASD). Heart murmurs were detected in 115 of 5124 term neonates within 1 month after birth. The babies were followed by echocardiographic examination with attention to the atrial septal area. Heart murmurs of 11 term neonates (9.6%) were associated with interatrial shunts consistent with ASD. The defect closed spontaneously in 7 out of the 11 neonates by 18 months of age. Two neonates showed evidence of right ventricular overload from early infancy. This study showed that nearly 1 neonate in 10 with a heart murmur up to 1 month after birth had an interatrial shunt associated with ASD. We concluded that the absence of a flap sign (valve-like openings of the defects) affects the development of the heart murmur of ASD found in the neonatal period.  相似文献   
19.
20.
BACKGROUND: Combination chemotherapy using an oral combination of uracil and tegafur (UFT) plus cisplatin and concurrent thoracic radiotherapy is reported to have a high response rate and less toxicity for locally advanced non-small-cell lung cancer (NSCLC) patients. We performed a phase II trial using this chemoradiotherapy as an induction treatment. METHODS: Patients with marginally resectable stage IIIB NSCLC, an age younger than 70 years, a performance status of 0 or 1, and good organ function were eligible. The UFT (400 mg/m(2)) was administered orally on days 1 through 14 and 22 through 35 and cisplatin (80 mg/m(2)) was injected intravenously on days 8 and 29. Radiotherapy with a total dose of 40 Gy was delivered in 20 fractions from day 1. A surgical resection was performed from 3 to 6 weeks after completing the induction treatment. RESULTS: Twenty-seven patients, 18 male and 9 female with a median age of 56 years and ranging from 36 to 69 years, were entered into the phase II trial. Clinical T4 and N3 cancers were observed in 22 and 7 patients, respectively. Twenty-five (93%) achieved a partial response. The most frequently observed adverse event was grade 3 leukopenia in 26%. Of 25 patients who underwent a thoracotomy, 22 had a tumor resection. In all 22 patients a complex resection including a resection of the superior vena cava, carina, and vertebrae was required. Operative morbidity and mortality rates were 36% and 4% respectively. The calculated 1-year and 3-year survival rates of all 27 patients were 73% and 56% respectively. CONCLUSIONS: Chemotherapy using UFT plus cisplatin and concurrent radiotherapy as induction treatment and a surgical resection for patients with marginally resectable stage IIIB NSCLC is feasible and promising. However it is difficult to conduct multi-institutional trials even for selected stage IIIB disease as a complex resection in almost all patients is necessary.  相似文献   
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