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61.
Cerebral intraparenchymal cysts without communication with the ventricles are very rare. We report four such cases with no relevant past history or evidence of infection, haemorrhage, trauma, tumour or congenital neural tube defect. At operation smooth wailed cysts with an ependymal-type lining were found. To the best of our knowledge, we present the first correlation of their pathological and radiological features (including magnetic resonance imaging). We also review the literature on these cysts.  相似文献   
62.
The structure of bromine residue compounds was investigated by X-ray absorption fine structure (XAFS) in order to interpret where and how bromine is present in carbons with different degrees of graphitization. The residue compounds can be classified into three groups, as obtained from X-ray absorption near edge structure (XANES) spectra and the values of the intramolecular distance rBr–Br determined by extended X-ray absorption fine structure (EXAFS). In Group I, prepared from the host carbons heat treated at temperatures higher than 1900 °C, bromine exists in the interlayer space of graphite in the form of Br2 molecules with interaction of the π electrons of graphite. In Group III, from carbon heat treated at 1000 °C, most of the bromine probably reacts with carbon atoms having a dangling bond or functional groups. For Group II, where the host carbons are heat treated at intermediate temperatures, it is likely that bromine exists in undeveloped defects with a unique electronic state.  相似文献   
63.
Much of the morbidity and mortality seen in cystic fibrosis (CF) is related to chronic infection of the respiratory tract with Pseudomonas aeruginosa. Some studies have attributed the strong relationship between CF and Pseudomonas colonization to the presence of increased numbers of specific cell-surface receptors, although other work suggests that this relates to the presence of mucus. Several groups are now assessing the use of gene transfer as a novel form of treatment for CF. We have examined whether P. aeruginosa binding to freshly obtained CF respiratory epithelial cells is increased, and have studied the effects of transfer of the CF transmembrane conductance regulator (CFTR) gene on this attachment. Binding of P. aeruginosa to noncultured nasal epithelial cells from both CF patients (n = 31) and healthy controls (n = 15) was studied with scanning electron microscopy. Binding was also assessed for CF cells following transfection with CFTR/liposome complexes. Epifluorescence microscopy was used to assess the effects of gene transfer on chloride fluxes. Adherence of P. aeruginosa directly to the cell surface of CF airway epithelium was significantly (P < 0.001) increased over that in non-CF controls. Liposome-mediated CFTR gene transfer resulted in a significant (P < 0.01) reduction in the numbers of bacteria bound to ciliated epithelial cells. Fluorescence microscopy confirmed correction of the basic chloride defect. Thus, in CF, the absence of normal CFTR results in increased binding of P. aeruginosa to respiratory epithelial cells. This abnormality can be corrected in vitro by restoration of CFTR function. This has important implications both for the pathogenesis of CF and for the future application and assessment of gene therapy for this disease.  相似文献   
64.
We report a rare case of portal-hepatic venous shunt through an enormous portal aneurysm complicated by pulmonary hypertension. A 66-year-old woman was admitted to our hospital for hepatic encephalopathy. Chest roentgenography revealed pulmonary hypertension. Computed tomography and ultrasound examination demonstrated a shunt between the portal and hepatic veins through an enormous portal aneurysm. The diagnoses of portal-hepatic venous shunt and pulmonary hypertension were confirmed by hepatic venous catheterization and cardiac catheterization. Pulmonary hypertension might result from the effects of vasoconstrictive agents, which should be metabolized by the liver in normal subjects, passing through the intrahepatic shunt into the lung.  相似文献   
65.
A new chemical sensing system using an electrical oscillator has been developed. This sensing system measures the electrical ‘non-linearity’ at the surface of an electrode immersed in a test solution: a sinusoidal voltage is applied to the electrode and the higher harmonics of the output current are obtained by Fourier transformation. This sensing system has been used to detect and quantify surfactant molecules in solutions. The relative intensity P2/P1 of the peaks of the second (P2) and first (P1) harmonics in the output current was found to be linearly correlated with the logarithms of the concentrations of cationic surfactants such as cetylpyridium bromide (CPB) and cetyl-N,N,N-trimethylammonium bromide (CTAB), but not with those of the anionic surfactant sodium dodecyl sulfate (SDS) or the neutral surfactant Triton X-100. The reproducibility of this sensing system was shown to be excellent.  相似文献   
66.
Foreign body (FB) injury from aspiration or ingestion is a common pediatric health problem. Diagnosis relies on clinical judgment plus medical history, physical examination, and radiographic evaluation. A multi-institutional review of 1269 FB events revealed that 85% were correctly diagnosed following a single physician encounter. However, 15% of the children had an elusive diagnosis (>1 week), despite previous evaluation. Delays in diagnosis were seven times more likely to occur in aspirations than in ingestions. Secondary injuries (e.g., pneumonia and atelectasis) occurred in 13% of airway FBs but in only 1.7% of esophageal FBs. Plain radiographs were used in 82% of children, and special studies (e.g., fluoroscopy) in only 7%. We conclude that diagnosis of FB injury in children is frequently achieved at the initial evaluation but that continued surveillance by follow-up visits to health care facilities from parents and other caretakers is important, to reduce pulmonary injuries.  相似文献   
67.
68.
Purpose:  Performed free coagulant hemodialysis to patients having hemorrhage with the hope to avoid aggravation of bleeding caused by anticoagulant agent from dialysis. Method:  Examined 19 cases of patients with bleeding tendency, whether it is possible to perform free coagulant hemodialysis by using PAES membrane, EVAL membrane, PS membrane, Cellulose triacetate membrane and Vitamin‐E modified‐dialysis membrane. Result:  With PAES membrane, the result showed a non‐ blockade rate of 91% after four hours and 100% after two hours. Therefore, blockade was prevented with a fairly high rate. In cases of blockade, most of them were possibly avoidable with a little contrivance as the reason were lack of establish blood flow rate, faulty position of a needle, etc. Conclusions:  By using PAES membrane, it was possible to perform free coagulant hemodialysis. In order to completely have no blockade of blood lines in the future, we must strive further on.  相似文献   
69.
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration.  相似文献   
70.
The inhibitory effects of a potent nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), on 2-deoxy-D-glucose (2-DG)-induced hyperglycemia were investigated in rats. L-NAME significantly inhibited 2-DG-induced hyperglycemia, although N(G)-nitro-D-arginine methyl ester (D-NAME) did not affect it. A similar NO synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), also inhibited 2-DG-induced hyperglycemia. The antagonistic effects of L-NAME are unrelated to the cholinergic system, since the muscarinic receptor antagonist scopolamine did not affect 2-DG-induced hyperglycemia. The neuronal NO synthase inhibitor 7-nitroindazole (7-NI) did not reduce 2-DG-induced hyperglycemia, but rather enhanced it. Our results suggest that NO may be involved in glucose homeostasis and that the inhibitory effects of L-NAME on 2-DG-induced hyperglycemia are not related to muscarinic receptors or neuronal NO synthase.  相似文献   
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