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11.
The effect of intravenous infusion of 10% glycerol on polymorphic delta waves of EEG was investigated in 13 patients (15 studies) with brain tumors in cerebral hemisphere. The delta waves were analyzed by two-dimensional EEG topography and power spectrum of delta waves (P(delta)) over the tumor, adjacent, and distant regions in the same hemisphere to the tumor, and ipsi- and contralateral hemispheres to the tumor. The data focus of EEG topography was well corresponded to the tumor and surrounding brain edema which visualized by x-ray CT-scan. In the patient with brain tumors with marked brain edema (group A, 11 studies), EEG topography showed marked reduction of delta focus within 20 minutes from the end of intravenous infusion of glycerol, and returned to preinfusion distribution within 60 minutes. In patients with absent to minimum brain edema (group B, 4 studies), delta focus showed the tendency to enlarge and returned to preinfusion state at 60 minutes after the end of glycerol infusion. In patients of group A, P(delta) of ipsilateral hemisphere to tumor decreased at the end of glycerol infusion, and showing maximal reduction ratio (30%, p less than 0.01) at 20 minutes, re-increased there-after. In group B, P(delta) of ipsilateral hemisphere showed no definite changes after the glycerol infusion. P(delta) of contralateral hemispheres in patients of both group A and B, showed similar reduction ratio and time course to those of ipsilateral hemisphere of group A.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
12.
Changes in cardiac myosin heavy chain (MHC) gene expression and isozyme transitions have been shown to be caused by developmental changes, hemodynamic overload, or the activity of various hormones. In this study, to examine whether caffeine, which has teratogenic effects on the fetal cardiovascular system, causes the distribution of cardiac MHC phenotype and, if so, to evaluate the mechanisms of the distribution of cardiac MHC phenotype by caffeine, we examined the effects of caffeine, theophylline, and cAMP on the cardiac MHC isoform transitions at the gene and protein levels using hypothyroid adult rats. Furthermore, we examined the expression of alpha- and beta-MHC gene in cardiac muscles of fetuses whose dams had received caffeine. The results showed that caffeine, theophylline, and cAMP caused accumulations of alpha-MHC mRNA and MHC isozyme V1. Furthermore, in the fetal hearts, it was recognized that caffeine induced an accumulation of alpha-MHC gene expression, as was also seen in the dams. However, this effect of caffeine on the heart was stronger in the fetus than in the dam. Intracellular cAMP concentration was increased by the administration of caffeine, theophylline, or cAMP, and the levels showed a positive correlation with those of alpha-MHC mRNA. These results suggest that the induction of alpha-MHC mRNA expression by the administration of caffeine may be induced by an increase in intracellular cAMP concentration.  相似文献   
13.
OBJECTIVES: To evaluate the accuracy of sonographic identification of the site of umbilical cord insertion (CI) at 18-20 weeks of gestation, to compare the sensitivities for detection of a velamentous cord insertion (VCI) secondary to a CI into the anterior, posterior or fundal wall, and to compare the intrapartum complications secondary to VCI into the upper, middle or lower third of the uterus. METHODS: As part of the routine ultrasound scan at 18-20 weeks' gestation we evaluated abnormal CI (VCI and marginal CI) and the location of the CI in the uterus in 3446 pregnancies. In cases of abnormal CI, the location of the CI was further classified as being in the upper, middle or lower third of the uterus. After delivery, the placenta and the umbilical cord were examined and intrapartum complications were compared with the location of the CI. RESULTS: The values for antenatal detection of VCI were: sensitivity, 25 of 40 (62.5%); positive predictive value, 25 of 25 (100%); and negative predictive value, 3406 of 3421 (99.6%). The sensitivity for cases in which the CI was located on the anterior wall was 12 of 13 (92.3%); when it was located on the posterior wall, the sensitivity was 11 of 22 (50.0%); and when it was fundal the sensitivity was 2 of 5 (40.0%). Variable decelerations were frequently observed with a VCI. In lower VCI cases, non-reassuring fetal heart rate patterns and emergency Cesarean sections occurred with a higher frequency than in cases with upper or middle VCI (P < 0.01). After delivery, the length of the aberrant vessels in cases of VCI by pathologic examination was 3.9 +/- 3.3 cm in the upper third, 4.7 +/- 4.6 cm in the middle third, and 10.6 +/- 6.8 cm in the lower third; thus, the aberrant vessel length was significantly greater when the CI was in the lower third of the uterus (P = 0.024). CONCLUSION: We have demonstrated that VCI with a lower CI site and with longer aberrant vessels is associated with various intrapartum complications. This finding has the potential for improving perinatal outcome.  相似文献   
14.
The effects of region of interest (ROI) selection and correction for Compton-scattered photons using a buildup factor on radionuclide left ventricular volumes calculated by the Links method were compared in 19 humans with contrast ventriculography and in phantoms. Three different methods of ROI selection were compared: a manual ROI, a second derivative ROI and a 50% count-threshold ROI. In phantoms without Compton scatter correction, volumes were overestimated by 30% (manual ROI), 20% (derivative ROI) and 1% (count threshold ROI). In subjects, results without Compton scatter correction were similar with overestimates of 50% (manual ROI) and 20% (derivative ROI) and an underestimate by 3% (count threshold method). Correction for Compton-scattered photons with the use of a phantom-derived buildup factor resulted in improved accuracy for the manual ROI (+15%) and the derivative ROI (0%). A 50% count threshold ROI following interpolative background subtraction allows the accurate calculation of cardiac volumes without the need for scatter correction, while a second derivative ROI method requires a correction for Compton scatter with the use of a buildup factor.  相似文献   
15.
We reported an autopsy case of a 14-year-old girl with cardiac myxoma, presenting sudden onset of consciousness disturbance and right hemiplegia while running in an 800 meter race. Though CT scan showed no abnormal findings, cerebral angiogram revealed an embolic stenosis of the left middle cerebral artery, and abdominal aortogram showed complete obstruction of the bilateral common iliac artery. Histological study of emboli taken from obstructed femoral arteries showed systemic embolization of the cardiac myxoma. She died three days after admission. Autopsy was performed. Myxoma tissue was not found, but its stalk was left in the left atrial septum. The brain was very edematous, and a myxoma emboli was found in the left middle cerebral artery. Systemic embolization of myxoma to spleen, kidneys, liver, pancreas, etc. was found histologically. Left atrial myxoma is a rare but potentially treatable cause of stroke, and should be included in the differential diagnosis of cerebral vascular disease, especially in young patients.  相似文献   
16.
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders.  相似文献   
17.
The authors report on 48 patients with calculous pyelonephritis. Urinary obstruction was caused by renal calculi in 21 patients and ureteral calculi in 27. Urine cultures were positive in 87.5% and bacteremia was seen in 70%. The common organisms in urine and blood culture wereE. coli, Proteus and Klebsiella. Septic shock occurred in 10 (20.8%) out of 48 patients. Calculous pyelonephritis with urinary obstruction is a very serious condition.  相似文献   
18.
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.  相似文献   
19.
The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI.  相似文献   
20.
OBJECTIVE: Pulmonary metastasis of non-small cell lung cancer is classified as an advanced disease stage, with limited indications for surgical treatment. However, the prognosis of patients with pulmonary metastasis of non-small cell lung cancer is better than that of patients with distant metastases. The purpose of the present study was to analyze and detect possible prognostic factors in surgically treated patients with ipsilateral pulmonary metastasis of non-small cell lung cancer. METHODS: Among 1198 patients with non-small cell lung cancer who underwent surgery at Kurashiki Central Hospital (Okayama, Japan) from April 1982 to March 2004, a total of 48 (4.0%) patients with pathologically diagnosed ipsilateral pulmonary metastasis were retrospectively evaluated. The median follow-up time was 20.5 months (range 1-103 months) and 37 patients (77.1%) were completely followed up until their death or more than 5 years after the operation. RESULTS: Among the 48 patients, 31 (64.6%) patients had metastatic nodules in the same lobe as the primary tumor (PM1) and 17 (35.4%) patients had metastatic nodules in different ipsilateral lobes (PM2). There was no significant difference in survival between patients with PM1 and the other patients with pT4-stage IIIB, or between patients with ipsilateral PM2 and the other patients with stage IV. Univariate analysis of postoperative survival stratified according to clinicopathologic factors revealed significant differences for the radicality of resection (complete vs. incomplete), tumor size (0-30 vs. >30mm) and pathological nodal (pN) factor (among pN0, pN1 and pN2-3). Multivariate analysis revealed that tumor size (0-30 vs. >30mm) and pN factor (pN0-1 vs. pN2-3) were independent prognostic factors. CONCLUSIONS: The results of our study suggest that undergoing a complete resection, having a tumor size of 30mm or less and having no mediastinal lymph node metastases were better prognostic factors for surgically treated patients with ipsilateral pulmonary metastasis of non-small cell lung cancer.  相似文献   
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