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41.
Most of "so-called" posterior communicating artery aneurysms previously reported, originated from the internal carotid-posterior communicating junction. Aneurysms arising from the posterior communicating artery itself are very rare. The abducens nerve palsy caused by cerebral aneurysm is also very rare. We are reporting a case with the saccular aneurysm arising directly from the distal half of the posterior communicating artery presenting the abducens nerve palsy. This 73-year-old woman who had no treatment with hypertension for several years was admitted for sudden onset of severe headache, vomitting and unconsciousness on March 1, 1984. She opened her eyes when addressed and had disorientation, urinary incontinence, right-hemiparesis and left-abducens nerve palsy. A 4-vessel angiography revealed the saccular aneurysm originating directly from the distal half of the posterior communicating artery. The patient underwent left-frontotemporal craniotomy on the 27th day after subarachnoid hemorrhage under Hunt & Kosnic Grade 3. The aneurysm originated directly from the distal half of the posterior communicating artery and directed inferior-posterior-laterally below the oculomotor nerve. The neck was successfully clipped. Immediate post-operative course was uneventful until the 7th day after surgery. On the 8th day she had hypertensive intraventricular hemorrhage and expired. The autopsy could not be obtained. The saccular "true" posterior communicating artery aneurysm with isolated unilateral abducens nerve palsy as seen in our case has not been reported. Considering the operative findings, we thought the aneurysmal dome contacted directly with the abducens nerve.  相似文献   
42.
The ACOSOG Z0011 trial has resulted in the omission of axillary lymph node dissection (ALND) in early breast cancer patients with one or two metastatic sentinel lymph nodes (SLNs). There has been increasing interest in the necessity of intraoperative assessment of SLNs in patients treated based on the Z0011 criteria. We evaluated the utility of intraoperative assessment in these eligible patients. A total of 1396 patients were treated following the Z0011 criteria from April 2012 to December 2019. We examined the proportion and clinicopathological features of patients who underwent ALND due to three or more metastatic SLNs and the sensitivity of intraoperative assessment. Only 16 (1.1%) patients had three or more metastatic SLNs diagnosed by intraoperative assessment, and they immediately underwent ALND. Of the clinicopathological factors, high clinical tumor stage (p = 0.002) and high Ki-67 labeling index value (p = 0.056) were more likely to be associated with the presence of three or more metastatic SLNs. The major independent risk factor for three or more metastatic SLNs was high clinical tumor stage (OR 3.94 [95% CI 1.42–11.0]; p = 0.009). Intraoperative assessment had low sensitivity (70.5%) and a high false-negative rate (29.5%) in detecting SLN metastases. The main finding of our study was the small proportion of patients who required ALND due to three or more metastatic SLNs according to the Z0011 criteria. The Z0011 strategy enables intraoperative assessment of SLNs to be omitted in early breast cancer patients.  相似文献   
43.
Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
44.
45.
The collagen cross-links, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) excreted in urine have recently been suggested as new markers of bone metastasis. In a pilot study we measured Pyr and D-Pyr in 61 patients with breast cancer, 16 with known bone metastasis and 45 with no recognized metastasis in bone. Twenty healthy female subjects were also measured as controls. The mean values (+/-SD) of Pyr and D-Pyr in the group with bone metastasis were significantly higher (Pyr: p<0.01, D-Pyr: p <0.05) than those in the group without bone metastasis and in the control group. The mean (+/-SD) values of postmenopausal women were significantly higher than those of premenopausal in the group without bone metastasis (p<0.05) and in the control group (p<0.01). Therefore, the effect of menopause should be taken into account in the diagnosis of bone metastasis by assays of Pyr and D-Pyr. Setting the cut-off values (mean + 2SD of the values of control) for pre and postmenopausal patients, the accuracy for Pyr was 71.4% in premenopausal and 75.8% in postmenopausal patients; and for D-Pyr it was 71.4% and 78.8% respectively. We consider that measurement of urinary collagen cross-links assays can contribute to the early detection of metastatic spread to bone in breast cancer.  相似文献   
46.
We synthesized 18F-FDG by using an automated synthetic apparatus "FDG MicroLab" (GE Medical Systems) which produces 18F-FDG by a solid phase 18F-fluorination. Its quality and reproducibility were evaluated in order to assess feasibility of the apparatus for routine clinical production of 18F-FDG. For 5 consecutive 18F-FDG synthesis, target irradiation was carried out at 15 microA for 60 min. 18F-FDG was obtained in 50 min after EOB with an end-of-synthesis yield of 9.34 +/- 1.06 GBq. Radiochemical yield and radiochemical purity were 47 +/- 3% (decay corrected) and 98.0 +/- 0.5%, respectively. Other several quality control parameters tested conformed with "Standards of Compounds Labeled with Positron Nuclides" (RADIOISOTOPES, 44, 1995). Thus, the automated synthetic apparatus "FDG MicroLab" has proven to stably produce 18F-FDG with high yield and high purity. The apparatus is feasible for routine clinical production of 18F-FDG.  相似文献   
47.
The rapid development of nuclear medicine instruments and the widespread availability of new radiopharmaceutical agents has created a new era of nuclear cardiology. This review will introduce new techniques beyond perfusion and function that have recently become available in Japan. Tc-99m perfusion imaging agents provide excellent myocardial perfusion images that may enhance diagnostic accuracy in the study of coronary artery disease. In addition, greater photon flux from the tracer permits simultaneous assessment of regional perfusion and function with the use of first-pass angiography or ECG-gated acquisition. In addition, Tc-99m perfusion agents are available for acute patients in emergency departments. When the tracer is administrated at both the acute and subacute phases of myocardial infarction, perfusion SPECT imaging permits accurate estimates of areas at risk and salvaged myocardium. Nuclear cardiology has progressed toward biochemical imaging in vivo. Positron emission tomography (PET) enables metabolic assessment in vivo. Preserved FDG uptake indicates ischemic but viable myocardium that is likely to improve regional dysfunction after revascularization. While FDG-PET is available only in a limited number of facilities, FDG-SPECT using ultrahigh energy collimators and branched fatty acid analog I-123 BMIPP SPECT offer potential for metabolic imaging in routine clinical settings. Less uptake of BMIPP than thallium is often observed in the ischemic myocardium and hypertrophic cardiomyopathy. Such a perfusion-metabolic mismatch as that in FDG-PET seems to be similarly observed in BMIPP SPECT. Severe ischemia is identified as reduced BMIPP uptake at rest despite normal or normalized perfusion, suggesting a significant role of BMIPP in ischemic memory imaging. I-123 MIBG uptake in the myocardium reflects adrenergic neuronal function in vivo. In the study of coronary artery disease, neuronal denervation is often observed around the infarcted myocardium and post-ischemic region as well. More importantly, reduced MIBG uptake in these patients can assess the severity of congestive heart failure. In addition, the improvement in MIBG can be seen in relation to improved patient condition following medical treatment. These new techniques will provide insights into new pathological states in ischemic heart disease and a variety of myocardial disorders. Nuclear cardiology plays an important role in selecting optimal treatments for these patients.  相似文献   
48.
Ischemic "cross" tolerance in hypoxic ischemia of immature rat brain   总被引:13,自引:0,他引:13  
Wada T  Kondoh T  Tamaki N 《Brain research》1999,847(2):227-307
The phenomenon of ischemic tolerance has been closely associated with the expression of heat shock proteins but recently, stress tolerance not related to hsp72 has been reported. In the present study, we focused on ischemic tolerance induced by hypoxia and hyperthermia in neonatal rat brain and analyzed the expression of hsp72. In a neonatal rat model of hypoxic ischemia (H-I), preconditioning by whole-body hyperthermia or hypoxia was induced 24 h prior to the ischemia. Brain damage was histologically evaluated and the expressions of hsp72 were analyzed. Hyperthermic preconditioning at 41 degrees C for 15 min, as well as hypoxic preconditioning with 8% hypoxia for 3 h, had almost complete neuroprotective effects. However, we failed to detect the expression of hsp72 in any of preconditioning. Only the H-I insult itself induced hsp72 in the dorsal striatum and slightly in the thalamus and the hippocampus. Hyperthermic preconditioning has neuroprotective effects which are comparable to hypoxic preconditioning in immature brain. The expression of hsp72 is not likely necessary for the ischemic tolerance in immature brain.  相似文献   
49.
We examined 133 patients with Kienbock's disease, five of whom had bilateral disease. There were 47 women and 86 men. The mean age of patients was 42.7 years (range, 14-80 years). The frequencies of involvement of the right and left sides were approximately equal for women, but male patients tended to have right wrist joint involvement. The side of the affected wrist in the female group differed significantly from that in the male group. The age at onset for women was significantly higher than that for men. The percentage of manual workers was significantly lower among women than among men. The characteristics of Kienb?ck's disease in women differed from those in men and those previously reported for this disease. These findings suggest that the pathogenesis of Kienb?ck's disease in women differs from that in men.  相似文献   
50.
PURPOSE: To study the effects of nilvadipine, a Ca2+ antagonist, on tissue circulation in the optic nerve head (ONH), choroid, and retina in rabbits and on the ONH circulation in normal tension glaucoma (NTG) patients. METHODS: Nilvadipine (3.2 microg/kg) or vehicle solution was injected intravenously into urethane-anesthetized rabbits, and the normalized blur value (NB), a quantitative index of in vivo tissue blood velocity, was measured in the choroid and in an area of the ONH and retina free of visible surface vessels before and for 90 minutes after injection, using the laser speckle method. The effects of nilvadipine on the ONH circulation was also studied using the H2 gas clearance method in separate groups of rabbits. Oral nilvadipine (4 mg/d) or placebo was administered to NTG patients in a double-masked manner, and NB in an area of the ONH rim free of visible surface vessels was measured by the same method before and 2, 4, 8, and 12 weeks after administration. RESULTS: The NB obtained from the ONH, choroid, or retina during the experimental period was increased by approximately 10% to 25% in the nilvadipine group compared with the NB in the control group (P < 0.0001, ANOVA), although systemic condition parameters and intraocular pressure (IOP) showed no significant intergroup difference except for a transient decrease in blood pressure in the nilvadipine groups. Blood flow rate in the ONH determined by the H2 gas clearance method also showed an approximately 25% increase in the nilvadipine group. The NB in the ONH of the oral nilvadipine-treated patients was significantly increased, by approximately 20% compared with the placebo-treated patients throughout the follow-up period. No significant intergroup difference was seen in blood pressure, pulse rate, or IOP. CONCLUSIONS: Nilvadipine increased blood velocity and, probably, blood flow in the ONH, choroid, and retina of rabbits. It also increased blood velocity in the ONH of NTG patients.  相似文献   
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