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101.
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The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity.  相似文献   
103.

Background  

It has been observed that ras-transformed cell lines in culture have a higher phosphatidylcholine (PC) biosynthesis rate as well as higher PC-degradation rate (increased PC-turnover) than normal cells. In correspondence to these findings, the concentrations of the PC-degradation product lyso-phosphatidylcholine (LPC) in cancer patients were found to be decreased. Our objective was the systematic investigation of the relationship between LPC and inflammatory and nutritional parameters in cancer patients. Therefore, plasma LPC concentrations were assessed in 59 cancer patients and related to nutritional and inflammatory parameters. To determine LPC in blood plasma we developed and validated a HPTLC method.  相似文献   
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The depth and extent of the invasion of the skull base by a tumor are the most critical information for successful en bloc resection of the tumor. The only means available for the evaluation of these factors are CT or MRI images. In order to clarify the ability of these imaging modes to delineate the invasion of the skull base, preoperative images of ten patients who underwent en bloc resection of skull base tumors at Kobe University Hospital were compared with the histopathological findings of the resected specimens. CT proved to be superior to MRI for evaluating bone destruction of the skull base. On the other hand, MRI provided more useful information about intracranial invasion than CT. As a hypertrophic linear shadow on Gd-enhanced MRI represented dural invasion or thickened dura mater adjacent to the tumor, this technique should be taken into consideration to determine the dural resection. We concluded that preoperative evaluation of the depth of skull base invasion by both CT and Gd-enhanced MRI is essential for planning complete tumor resection.  相似文献   
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Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese. WANG Tao, male, born in 1961, Associate Professor This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial No. WJ 01529).  相似文献   
108.
In embryology, a persistent connection of the left superior vena cava to the left atrium rarely coexists with a coronary sinus. We herein report an unusual case of persistent left superior vena cava terminating in a left atrium with normal coronary sinus, which was revealed at the time of permanent pacemaker implantation after a second operation for recurrent left atrioventricular valve regurgitation. Because this anomaly had gone undiagnosed at the first operation, we were unable to diagnose it prior to the second operation, because the preoperative coronary angiogram clearly demonstrated a coronary sinus that was not dilated. We would have repaired the anomaly using a patch or other procedure had it been diagnosed before the second operation in order to prevent cyanosis or brain complications secondary to right-to-left shunting. One should always be on guard for this rare condition.  相似文献   
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110.
Recently, enormous efforts to measure the quality of healthcare have been made to attain information on ways to improve the quality of healthcare. However, this area of research is still at an early stage of development and more research is required. This article outlines a framework by which the quality of healthcare can be analyzed on the basis of the three quality dimensions introduced by Donabedian. The article then goes on to test the validity of this (theoretical) framework within an empirical analysis.Because of increasing financial shortages within health systems, this article focuses on the treatment of myocardial infarction, which is one of the costliest and most prevalent diseases. This approach establishes a link between medical and economic problems. The variables for structure quality (i.e. number of cardiologists, number of catheterization facilities) were sourced and evaluated from the ‘Herzberichte der Jahrgänge’ (‘heart reports’) compiled by Bruckenberger for the period 1994–2004 for the 16 German federal states. Data from the Federation of Quality Assurance (BQS) were used for the evaluation of process quality (i.e. adequacy of indication for coronary angiography). Finally, administrative data from the German Federal Statistical office for 1994–2004 were used to determine the variables of outcome quality (i.e. standardized mortality rate due to myocardial infarction, potential years of life lost <70 years due to myocardial infarction).Three hypotheses were tested using panel data: (i) a better structure and/or process quality increases the probability of getting a better outcome quality for the clinical picture under observation; (ii) by employing additional input factors (such as additional catheterization facilities), the probability of getting a good outcome quality is increased; and (iii) in addition to structure quality and process quality, factors lying outside of the sphere of influence of the health system have an additional influence on outcome quality (marginal gains would decrease in this case). Three models were used to test these hypotheses using fixed effects estimation.The empirical analysis produced three results. First, the analysis confirms the predicted causality between the different dimensions of quality of care for the German federal states. Notably, the number of catheterization facilities has a highly significant positive influence on the outcome quality. Second, support is found for decreasing marginal gain of inputs. Third, a good structure and a good process quality alone cannot guarantee good outcome quality. However, the analysis also showed that, in addition to healthcare provided, there are other determinants that also affect the outcome quality of healthcare. Further empirical investigation regarding the influence of these factors on the outcome dimension could elaborate on our findings and deliver additional insights.  相似文献   
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