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1.
Trauma und Berufskrankheit - Eine Vielzahl von Präventivmaßnahmen sowie Fortschritte in der medizinischen Akutversorgung von Unfallpatienten führten in den letzten Jahren zu deutlich... 相似文献
2.
The synthesis of 15 possible metabolites of prolintane (1) (Katovit) which is used in the treatment of blood pressure disregulations is described. Furthermore, the preparation of the enantiomers of 1 is reported, starting with R-(+)- and S-(-)-phenylalaninol respectively. 相似文献
3.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
4.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
5.
During the time from 1982/83 the intracranial pressure was continuously measured from patients who were polytraumatized and also had severe head injuries. In 53% of these cases the first readings could be obtained within 6 hours after the injury and in 33% first after 12 hours. During the time of evaluation this relationship shifted to earlier implantation. From 27% of these patients the intracranial pressure values fell into a range that instigated immediate therapeutical measures. This proves how important it is to have a direct reading from the intracranial pressure as soon as possible after injury. The aspects of therapy by increased intracranial pressure were discussed. 相似文献
6.
7.
The formation of postsynaptic clusters of various ligand-gated ion channels is regulated by receptor activity. Here we describe the developmental- and activity-dependent modification of N-methyl-D-aspartate (NMDA) receptor clustering in spinal cord neurons in vitro detected by immunofluorescence analysis using subunit and splice variant specific antibodies. NMDA receptors form synaptic and extrasynaptic clusters with sequential changes in subunit composition during in vitro development. During the first week of in vitro culture, a NR1 splice variant containing the C2-carboxy terminus and lacking the N1-cassette and the NR2B subunit are the prevailing components of receptor clusters at synaptic and extrasynaptic sites. After 3 weeks in culture (days in vitro [DIV] 22), the numbers of postsynaptic receptor clusters with N1-containing NR1 splice variants and NR2A subunits are upregulated. At DIV22, C2-specific clusters are abundant and are predominantly localized at postsynaptic sites, whereas the total number of C2'-clusters in dendrites is much lower and these clusters are localized mostly extrasynaptically. However, upon chronic inhibition of NMDA receptor activity in DIV8 and DIV22 cultures with MK801, the number of postsynaptic NR1-C2' subunit clusters is strongly upregulated. In contrast, numbers of NR1-C2 clusters are only modestly increased in DIV8 and not changed in DIV22 cultures upon MK801 treatment, suggesting a specific role of NR1 carboxy-terminal sequences in the activity-dependent synaptic targeting of NMDA receptor clusters of spinal cord neurons. 相似文献
8.
Changes in tonic descending inhibition of spinal neurons with articular input during the development of acute arthritis in the cat. 总被引:10,自引:0,他引:10
1. In 15 alpha-chloralose-anesthetized cats we studied the presence of tonic descending inhibition (TDI) of spinal neurons with input from the knee and its modulation during an acute inflammation of this joint. TDI of spinal neurons with articular input was assessed by applying reversible cold blocks to the lower thoracic cord. The amount of descending inhibition was estimated from the induction and/or increase of resting discharges and of the responses to mechanical stimuli to the knee and other structures during the transitory and reversible blocks. In each experiment one or a few neurons were investigated while the joint was in normal condition [altogether 15 nociceptive-specific (NS) and 6 wide-dynamic-range (WDR) neurons]. One of the neurons was then selected for long-term recordings during which an acute inflammation in the knee was induced by the intra-articular injection of kaolin and carrageenan. Before and during developing arthritis, cold blocks were applied to examine whether the amount of TDI would change during the inflammatory process. 2. The neurons with input from the normal knee were under TDI because application of the cold block induced or increased resting discharges and the responses to noxious compression of the knee and the adjacent thigh and lower leg. In 10 of 15 NS neurons, the response threshold was lowered into the innocuous range. In 9 of 17 cells tested, the excitatory receptive field expanded to the ipsilateral paw, and 4 neurons became inhibited by paw compression. Seven of 18 neurons tested revealed inhibitory receptive fields on the contralateral leg during cold block. The neurons were located in laminae IV-VII. 3. Fourteen neurons were continuously monitored during development of inflammation, and changes in the effectiveness of TDI were assessed by blocking the cord before and during the development of arthritis. In most neurons baseline resting activity in the intact state of the cord increased while the arthritis developed. This inflammation-evoked enhancement of resting discharges was more pronounced during periods of spinalization. Consequently, the differences between the resting discharges in the cold-blocked and the intact state were progressively enhanced in arthritis. 4. After induction of arthritis, the responses to compression of the knee joint increased in the intact state as well as during cold blocks. In 11 of 14 neurons, the differences between the responses in the spinal and intact state were progressively enlarged during the development of inflammation. A similar result was obtained for flexion of the injected knee.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
9.
Neugebauer E. Beckurts T. Lorenz W. Maroske D. Merte H. Horeyseck G. Dietz W. 《Inflammation research》1986,18(1-2):23-29
The hypothesis of a causal relationship between a progressive and unrestrained increase of tissue histamine formation by activation of an inducible histidine decarboxylase (HDC) and lethality in endotoxic shock (Schayer's induced histamine concept) was tested in a standardized rat endotoxic shock model.Initial enzyme identification studies in the rat shock liver (8 hrs after endotoxin challenge) clearly demonstrate that the induced histidine decarboxylase is an acid (specific) HDC. The succeeding randomized, controlled study with appropriate inhibitors of the enzyme, -methyl-histidine (competitive inhibitor) and -fluoromethyl-histidine (irreversible inhibitor) using doses of 2, 20 or 100 mg/kg showedno significant effect on the survival rate of rats in endotoxin shock. The survival rate of the non-treated endotoxin control group (NaCl) was 25%; all methylprednisolone treated rats (50 mg/kg) survived.Thus, the induced histamine isnot a predominant factor (necessary or sufficient determinant) for the lethal outcome in rat endotoxic shock. The protective effect of MP isnot predominantly due to the inhibition of the induced histidine decarboxylase. The use of HDC-inhibitors as the appropriate instruments for evaluation of the significance of this mechanism is discussed.Clinic of General Surgery, City Hospital Sieburg. 相似文献
10.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献