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21.
For cardio-pulmonary resuscitation there are standardized treatment concepts, but there have been few prospective investigations examining the efficacy of prehospital advanced trauma life support and its effect on the outcome in patients with severe head injury and multiple trauma treated within the German emergency system. The results of this study underline the importance of intensive prehospital treatment and highlight some problems that should be taken into account in future in the training of emergency physicians. Methods. A total of 179 patients with cerebral trauma were investigated. Data obtained included demographic and logistic data of the patients and the emergency physicians, diagnoses and treatment at the scene of the accident and state of the patient on admission in each case. Having divided the patients into three groups by severity of the trauma, we distinguished between sufficient and insufficient treatment and assessed infusion therapy, ventilatory support, positioning and immobilization, and analgesic and sedative therapy. For statistical analysis of the data we used χ2-test and Fisher's exact test. P<0.05 was considered significant. Results. There were 102 patients who had sustained a cerebral trauma without other life-threatening lesions (score 1), 40 with multiple trauma (score 2) and 37 with multiple trauma (score 3). On average 2.4?IV lines were established and the patients received 1186±765?cc of crystalloid in addition to 801±411?cc of colloid fluids. In all groups, patients who received adequate infusion therapy had a better outcome; even in the group with score 1 significantly fewer had a fatal outcome. In all, 167 (93%) patients had endotracheal tubes placed, and in 150 cases (84%) ventilatory therapy was considered sufficient. The proportion of score 1 patients with sufficient ventilatory support who had a fatal outcome was significantly lower than that in the group with insufficient treatment. In patients with multiple trauma we could not separate the benefits of sufficient respiratory therapy and infusion therapy. In only 54% of the cases a vacuum mattress was used and in only 41% the patients were positioned with the upper part of the body elevated by 30°. These were 28 patients (16%) who received neither analgesics nor sedatives. Regardless of the quality of prehospital treatment of isolated head injury, a Glasgow Coma Scale (GCS) score lower than 5 involved a very high mortality and all patients with a GCS score of 9 or more survived. In the group with GCS scores between 5 and 8, however, significantly more of the patients who received adequate treatment survived (82.5% vs 40%). Conclusions. The present study confirms that sufficient advanced trauma life support can improve the outcome of trauma victims with cerebral trauma. Adequate infusion and respiratory therapy reduce the mortality among such patients significantly. In patients with multiple trauma a clear positive effect of generous infusion therapy also is evident. The clearest effect of sufficient prehospital treatment is seen in patients with isolated cerebral trauma and a GCS score between 5 and 8. These results demonstrate the importance of advanced trauma life support and show emphatically that the so-called scoop-and-run strategy should be abandoned when resources are available for extended preclinical emergency treatment. On the other hand, we detected some problem areas in the prehospital treatment of trauma victims, such as positioning, immobilization and drug therapy with analgesics and sedatives. These findings allow us to pinpoint specific points that should be stressed in the training of emergency physicians and paramedics.  相似文献   
22.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
23.
By employing neoglycoproteins (NGP) and glycosaminoglycans, the detection of endogenous glycoligand-binding sites has become possible. Monitoring specific binding of 11 of these sugar receptor-specific tools, 13 trypanosomatids of monogenetic genera Blastocrithidia, Crithidia, Herpetomonas , and Leptomonas and digenetic genera Endotrypanum , Leishmania , and Sauroleishmania were analysed by agglutination and fluorescence assays. NGP showed agglutination reactions only with the digenetic but not with the monogenetic species. Sensitive flow cytofluorimetric investigations revealed that the apparently different reactivity to NGP is due to a pronounced quantitative difference in expression of binding sites between mono- and digenetic flagellates. Moreover, flow cytofluorimetry was used to demonstrate the occurrence of receptor sites for heparin on the cell surfaces of all trypanosomatids. An indication for a correlation of the binding capacity for the NGP N-acetyl-β-d-glucosamine and heparin to differences in the pathogenicity of parasites was observed for Leishmania donovani as well as Leishmania enriettii . Infective populations of these species contained a significantly higher number of cells which had bound N-acetyl-β-d-glucosamine and heparin than noninfective (long-term in vitro -cultured) populations. The results of the present report additionally support the hypothesis that lectin–carbohydrate interactions with neutral sugar moieties and heparin or heparin-like molecules participate in the interactions between trypanosomatids and host (cells), and that the detected binding sites for carbohydrates and heparin may thus be referred to as potential virulence factors.  相似文献   
24.
The hippocampus and amygdala, the entorhinal cortex and the parietal cortex participate, in that sequence, both in the formation and in the expression of memory for a step-down inhibitory avoidance task in rats. Bilateral infusion of AP5 or muscimol caused retrograde amnesia when given O min after training into both hippocampus and amygdala, when given or 180 min after training into the entorhinal cortex, or when given 180 min after training into the parietal cortex. Therefore, memory formation requires the sequential and integrated activity of all these areas mediated by glutamate NMDA receptors in each case. Pre-test administration of CNQX 1 day after training into hippocampus and amygdala, 1 or 31 days after training in entorhinal cortex, or 1, 31 or 60 days after training in the parietal cortex temporarily blocked retention test performance. Therefore, 1 day after training, all these brain structures are necessary for retrieval; 1 month later, the hippocampus and amygdala are no longer necessary for retrieval but the entorhinal and parietal cortex still are; and 60 days after training only the parietal cortex is needed. In all cases the mechanisms of retrieval require intact glutamate AMPA receptors.  相似文献   
25.
Purpose: A comprehensive pharmacokinetic study of leucovorin (5-formyltetrahydrofolate, 5-HCO-FH4) and its metabolites was conducted in plasma, liver and implanted tumor tissue from mice maintained on a low folic acid diet. While it has been previously demonstrated that the antitumor activity of fluorouracil (FU) can be potentiated by 5-HCO-FH4, the optimum time for administration of FU after 5-HCO-FH4, to maximally elevate the active folate metabolite methylenetetrahydrofolate in tumor has not been established. Human plasma studies have defined the pharmacokinetics of circulating 5-HCO-FH4 and its metabolites, but comparison with human tumor accumulation has not been practicable because of sampling difficulties. As an alternative, a mouse model system, based on low dietary folic acid, was used to evaluate plasma, liver and implanted tumor reduced folates after administration of 5-HCO-FH4.Methods: Plasma and tissue samples were collected from folate-deplete mice over a 12-h period after intraperitoneal administration of 90 mg/kg [R, S ] 5-HCO-FH4. Reduced folates were evaluated using a ternary complex assay. Results: The time at which max‐imal accumulation of parent compound and all metabolites, except 5-methyltetrahydrofolate (5-CH3FH4), occurred in tumor was the same as in plasma. Alternatively, peak liver accumulation was delayed relative to plasma for all folates except 5-CH3FH4. Conclusions: The results suggest that mouse plasma accumulation of reduced folates, with the exception of 5-CH3FH4, can predict tumor accumulation. Hence, evaluation of human plasma folate accumulation may potentially provide a means to improve the timing of the administration of FU relative to 5-HCO-FH4 to achieve a superior therapeutic outcome. Received: 24 July 1996 / Accepted: 29 October 1996  相似文献   
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Ninety-two patients and 28 staff members of an institute for mentally retarded patients were immunized intradermally with 2 microgram doses hepatitis B vaccine (HB-Vax), initially at month 0 and 1, and after evaluation followed by two booster injections at month 5 and 10, respectively. Blood samples were taken at months 2 and 11. Seroconversion rates of the two groups were similar on both occasions. Titre distributions for mentally retarded patients and staff members corrected for age, side effects and sex using multiple regression were significantly different at month 2 (p = 0.05) but not at month 11. Geometric mean titres for mentally retarded patients and staff members were 39 and 67 at month 2, respectively, and 1082 and 672 IU l-1 at month 11, respectively. Percentage anti-HBs/a(w) differed significantly between patients and staff members. Side effects, largely local (pigmentation), were observed with a frequency of about 35% in both mentally retarded patients and staff members. Since 92% of the mentally retarded patients had anti-HBs titres greater than 10 IU l-1 and approximately equal to 80% greater than 100 IU l-1, low dose vaccination, four injections by intradermal route, seems to be a suitable cost-reducing immunization system in institutes for mentally retarded patients.  相似文献   
29.
Vieth S  Torda AE  Asper M  Schmitz H  Günther S 《Virology》2004,318(1):153-168
The L RNA of three Lassa virus strains originating from Nigeria, Ghana/Ivory Coast, and Sierra Leone was sequenced and the data subjected to structure predictions and phylogenetic analyses. The L gene products had 2218-2221 residues, diverged by 18% at the amino acid level, and contained several conserved regions. Only one region of 504 residues (positions 1043-1546) could be assigned a function, namely that of an RNA polymerase. Secondary structure predictions suggest that this domain is very similar to RNA-dependent RNA polymerases of known structure encoded by plus-strand RNA viruses, permitting a model to be built. Outside the polymerase region, there is little structural data, except for regions of strong alpha-helical content and probably a coiled-coil domain at the N terminus. No evidence for reassortment or recombination during Lassa virus evolution was found. The secondary structure-assisted alignment of the RNA polymerase region permitted a reliable reconstruction of the phylogeny of all negative-strand RNA viruses, indicating that Arenaviridae are most closely related to Nairoviruses. In conclusion, the data provide a basis for structural and functional characterization of the Lassa virus L protein and reveal new insights into the phylogeny of negative-strand RNA viruses.  相似文献   
30.
Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general.  相似文献   
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