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51.
There were 2040 patients with temporomandibular joint (TMJ) diseases in the investigation including clinical, physiological, X-ray methods of research, contrast arthrotomography, computer arthrotomography and magnetic resonance tomography. The changes of structure in different lesions were estimated. The result of received data was elaboration of classification of TMJ internal derangements with estimation of clinical forms in according with structural changes and characteristics of syndromes. 相似文献
52.
SG Volsen NC Day AL McCormack W Smith PJ Craig RE Beattie D Smith PG Ince PJ Shaw SB Ellis N Mayne JP Burnett A Gillespie MM Harpold 《Canadian Metallurgical Quarterly》1997,80(1):161-174
The beta subunits of voltage-dependent calcium channels, exert marked regulatory effects on the biophysical and pharmacological properties of this diverse group of ion channels. However, little is known about the comparative neuronal expression of the four classes of beta genes in the CNS. In the current investigation we have closely mapped the distribution of beta1, beta2, beta3 and beta4 subunits in the human cerebellum by both in situ messenger RNA hybridization and protein immunohistochemistry. To our knowledge, these studies represent the first experiments in any species in which the detailed localization of each beta protein has been comparatively mapped in a neuroanatomically-based investigation. The data indicate that all four classes of beta subunits are found in the cerebellum and suggest that in certain neuronal populations they may each be expressed within the same cell. Novel immunohistochemical results further exemplify that the beta voltage-dependent calcium channel subunits are regionally distributed in a highly specific manner and studies of Purkinje cells indicate that this may occur at the subcellular level. Preliminary indication of the subunit composition of certain native voltage-dependent calcium channels is suggested by the observation that the distribution of the beta3 subunit in the cerebellar cortex is identical to that of alpha(1E). Our cumulative data are consistent with the emerging view that different native alpha1/beta subunit associations occur in the CNS. 相似文献
53.
G Metry G Wegenius B Wikstr?m V K?llskog P Hansell PG Lindgren H Hedenstr?m BG Danielson 《Canadian Metallurgical Quarterly》1997,52(6):1635-1644
The density of the lung reflects the total mass of fluid, air, and dry lung tissue per unit volume of the lung. Lung density can be measured by evaluation of attenuation of an electron beam with computed tomography (CT). This technique has been shown to be sufficiently reliable and sensitive to distinguish normal from abnormal lung water. The aim of this study was to find out whether lung density properly reflects the hydration status in hemodialysis patients in comparison with other standard methods. Fourteen hemodialysis patients, with an ultrafiltration ranging from 0.3 to 4.5 liters per session, underwent CT measurements of lung density, ultrasonographic measurements of the diameter of the inferior vena cava after quiet expiration (IVCe) and quiet inspiration (IVCi), and measurements of the hematocrit and plasma levels of the biochemical hydration markers cyclic guanosine monophosphate (cGMP) and atrial natriuretic peptide (ANP). These measurements were performed before and 3.5 to 4 hours after termination of dialysis. Quantitative estimates of lung density were obtained within pixels with CT numbers ranging between -1000 and -100 Hounsfield Units (HU), and compared with normal data from 18 normal controls. In normal controls, the lung density ranged from -800 to -730 HU. In hemodialysis patients, lung density was significantly higher than normal before dialysis (-678 +/- 96 HU, P < 0.01) and significantly decreased after dialysis (-706 +/- 92 HU, P < 0.05), indicating a decrease in fluid content of the lung. The density was normalized in 5 patients. A significant correlation was found between lung density and IVCe both before and after dialysis (r = 0.8, P < 0.01 for both). Change in density was significantly correlated to amount of ultrafiltration (r = 0.67, P < 0.01) and percent change in blood volume (r = 0.63, P < 0.05), indicating that lung density is greatly affected by changes in the extracellular fluid volume, mainly the intravascular volume. In conclusion, lung water reflects the hydration status in hemodialysis patients and can be monitored by measuring the lung density by CT. Accordingly, normalization of lung density can help to achieve a proper dry weight in these patients. 相似文献
54.
Intracerebral infection of mice aged 2-3 days with hepatitis C virus (HCV) from chronically infected suckling mouse brain cultures and porcine embryo cells resulted in the death of animals after 12-14 days. Repeated passages of HCV in animals decreased the incubation period to just 3-4 days. Blood serum of surviving mice collected during the 4th week postinfection contained antiHCV antibodies detected by enzyme immunoassay and hemagglutination inhibition test. The results are proof of creation of a new in vivo model of experimental HCV infection. 相似文献
55.
We have used gene disruption to isolate two talin (-/-) ES cell mutants that contain no intact talin. The undifferentiated cells (a) were unable to spread on gelatin or laminin and grew as rounded colonies, although they were able to spread on fibronectin (b) showed reduced adhesion to laminin, but not fibronectin (c) expressed much reduced levels of beta1 integrin, although levels of alpha5 and alphaV were wild-type (d) were less polarized with increased membrane protrusions compared with a vinculin (-/-) ES cell mutant (e) were unable to assemble vinculin or paxillin-containing focal adhesions or actin stress fibers on fibronectin, whereas vinculin (-/-) ES cells were able to assemble talin-containing focal adhesions. Both talin (-/-) ES cell mutants formed embryoid bodies, but differentiation was restricted to two morphologically distinct cell types. Interestingly, these differentiated talin (-/-) ES cells were able to spread and form focal adhesion-like structures containing vinculin and paxillin on fibronectin. Moreover, the levels of the beta1 integrin subunit were comparable to those in wild-type ES cells. We conclude that talin is essential for beta1 integrin expression and focal adhesion assembly in undifferentiated ES cells, but that a subset of differentiated cells are talin independent for both characteristics. 相似文献
56.
The surface chemical composition of whole cells and isolated cell walls of four coryneform bacteria and of a Bacillus brevis strain has been determined by X-ray photoelectron spectroscopy (XPS). The XPS data were converted into concentrations of model compounds: peptides, polysaccharides, and hydrocarbonlike compounds. The composition of the surface of B. brevis differed markedly from that of coryneforms: the peptide concentration was about twice higher in the former case, which is attributed to the presence of an S-layer at the cell surface; in contrast, the surface of coryneforms was rich in hydrocarbonlike compounds (about 40%), which was concomitant with a high water contact angle. The peptide surface concentration of the isolated cell walls of the five strains deduced from XPS data fitted well with the total peptide content determined by biochemical analysis, which supports the validity of XPS to determine the overall macromolecular composition of the bacterial cell surface. Compared to biochemical analysis of isolated cell walls, XPS analysis of whole cells provides information which concerns directly the cell surface (2- to 5-nm-thick layer) and is less subject to alteration via losses of cell wall constituents or contamination by intracellular compounds. 相似文献
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59.
PG de Visme 《Canadian Metallurgical Quarterly》1998,160(42):6088-6091
Ingestion of the increasingly popular designer drug, ecstasy, results in an acute increase in the brain's monoamines: serotonin, dopamine, and noradrenaline. Animal research involving ecstasy has shown lasting damage to serotonergic axons and terminals, leading to reduced serotonin transmission in the CNS. Moreover, several studies suggest that the ingestion of ecstasy may be toxic to the human serotonin system. In animals repeated ecstasy administration has not shown persistent behavioural changes. In humans long lasting alterations in sleep pattern, mental state, personality, and cognition have been reported after repeated ecstasy use. However, these results have not been replicated, and most of them originate from uncontrolled studies of rather small populations. 相似文献
60.
Absolute eosinophil counts were assessed in 15 African patients with proven endomyocardial fibrosis. Though the mean eosinophil count in patients with endomyocardial fibrosis was higher compared with the normals reported from Kampala (1-13 vs 0.72X10(9)/1), the absolute range was comparable. A high percentage of patients with endomyocardial fibrosis had malarial parasites, high malarial antibody titres, hookworms, or strongyloides, but the correlation of eosinophilia to various parasitic infections was poor. Both eosinophilia and parasitic infections are common in the tropics and they effect patients with endomyocardial fibrosis no more than the population at large. Other aetiological factors, genetic, environmental, and immunological, are felt to be important in the causation of endomyocardial fibrosis in Uganda and evidence for this is reviewed. Though there is a similarity in pathological features, African endomyocardial fibrosis is a distinct entity from L?ffler's endocarditis and cardiac lesions seen in eosinophilic leukaemia or reactive eosinophilia. There is no hard evidence to suggest that African endomyocardial fibrosis is a variant of L?ffler's endocarditis caused by parasitic infections via eosinophilia. 相似文献