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From October 1988 to January 1992, nine isolates of Pseudomonas aeruginosa carrying transferable plasmids encoding imipenem-hydrolyzing beta-lactamase (pI = c. 9.5) were recovered from nine different patients in a neurosurgical ward of a hospital in Japan. The beta-lactamase activities of the sonicated extracts from the transconjugants were inhibited by EDTA and this was partially reversible by the addition of zinc cation. The substrate specificity and pI of the beta-lactamase were similar to those of the metallo beta-lactamases from P. aeruginosa and Serratia marcescens TN9106. All strains were resistant to imipenem, carbenicillin and antipseudomonal cephems including ceftazidime, cefsulodin, cefpirome, while four and five strains were susceptible to piperacillin and aztreonam, respectively. Both low level imipenem resistance and high level cephem resistance were co-transferred with the production of metallo beta-lactamase, while resistance to piperacillin, aztreonam, and high level imipenem-resistance were not selected. Production of chromosomal cephalosporinase in piperacillin resistant strains was derepressed, and production of outer membrane protein of D2 was diminished in highly imipenem resistant strains. Six strains were isolated in 1991, and the amounts of antipseudomonal agents, especially imipenem, used in the neurosurgical ward increased markedly in this year. Only three of the nine isolates had the same serotype, pyocin type and phage type. Our results suggest that the repeated isolation of imipenem and cephem-resistant P. aeruginosa producing metallo beta-lactamase was related to the high usage of antipseudomonal beta-lactam antibiotics such as imipenem, and was exacerbated by the dissemination of a plasmid.  相似文献   
65.
A case of recovered memory of childhood trauma is reported with documented sexual trauma in early childhood, chronicled evidence of the absence of memory for traumatic experience over a period of time, and substantial evidence of 'spontaneous' recovery of memory. This account contains the first available prospective report of memory loss in a case in which there is both documented evidence of trauma and evidence of recovery of memory. The case emerged as part of a broadband, large-scale study of children followed closely from birth to adulthood which was not focused on memory for trauma. Prospective data gathered in a neutral research context, corroborated and supplemented by retrospective information, circumvent many limitations of previous retrospective accounts of recovered memories.  相似文献   
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In view of the biological relevance of triazole-based heterocyclic structures as antifungal, antiviral, and antitumor agents, we have synthesized a series of substituted pyrazolo[3,4-d]-1,2,3-triazoles (2e-h, 2j, 4b) which we evaluated for their cytostatic and antiviral (HIV-1 included) activity and for their capability to inhibit the multiplication of various human pathogenic fungi and bacteria. Moreover, the biological activities of a few compounds, namely pyrazolo[3,4-d]oxazoles (3a-e) and pyrazolo[3,4-d]-1,2,3-triazoles (2a-d, 4a, 5), previously obtained by us but not investigated for their biological activity, were also studied. Only compounds 3a-e were endowed with a significative antiproliferative activity on the human lymphoblastoid cell line MT-4 cells. All pyrazole derivatives proved ineffective in protecting cell cultures against the HIV-1-induced cytopathogenicity, and none of the compounds was active against the bacteria and fungi tested.  相似文献   
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In a sample of 13 full-term and 10 preterm infants, the development of kicking movements was studied at 6, 12, and 18 weeks (corrected) age. In healthy full-term infants some characteristics are strikingly stable, such as the duration of the flexion and extension phase and the within-joint organization. These parameters did not differ in preterm compared to full-term infants. For other features, however, developmental changes and differences were observed. Full-term infants tended to decrease their kick frequencies slightly with age. In preterm infants much higher initial kick rates were found, followed by a steep decrease, which resulted in kick frequencies comparable to the full-term levels after the (corrected) age of 12 weeks. There is a tight coupling between the movements in the different joints of the leg in full-term newborns. Preterm infants, in contrast, initially show much lower cross-correlations between hip and ankle and between knee and ankle. This is particularly the case for those preterm infants who were born before 32 weeks gestation. Again, the differences resolved after the age of 12 weeks, which might be related to a transformation in neural functions reported previously around this age. The initial differences in the characteristics of kicking appeared to be more readily explainable by differences in neurological condition than by contrasts in leg volume or postural control.  相似文献   
68.
OBJECTIVES: To assess the pathological staging and biochemical progression-free survival (assessed using serum prostate-specific antigen level) of patients with clinically localized prostate cancer using neoadjuvant androgen deprivation therapy (ADT) in combination with radical retropubic prostatectomy (RRP). PATIENTS AND METHODS: A prospective study was carried out on 69 patients with localized prostate cancer who were enrolled in a trial of 3 months of ADT followed by RRP (group 1). These patients were compared with 72 patients matched for age and clinical stage who declined ADT therapy and had RRP concurrently (group 2). Assignment to the individual treatment groups was thus determined by the patient's preference and not the physician's selection. Pathological staging and biochemical progression-free recurrence were compared between the groups. RESULTS: The rate of organ-confined (pT2) tumours was 74% in group 1 and 49% in group 2 (P < 0.01), and the rate of margin-negative tumours was 87% in group 1 and 64% in group 2 (P < 0.01). Within a median follow-up of 35 months, there was no significant difference in biochemical failure between the groups (P = 0.37). Patients with pT2 disease, regardless of treatment, had similar biochemical failure rates. In the patients with margin-positive disease, there was a significantly higher biochemical failure rate in group 1 (P = 0.02). CONCLUSIONS: The rates of organ- and specimen-confined disease were higher among the patients treated with ADT. The preliminary follow-up suggested that patients with pT2 disease after ADT have a biochemical progression-free recurrence rate similar to pT2 patients treated with RRP alone. Additionally, high biochemical failure rates in patients with margin-positive disease after ADT may identify a subset of more biologically aggressive tumours in need of early adjuvant treatment.  相似文献   
69.
Cocaine-using methadone-maintenance patients were randomized to standard contingency management (abstinence group, n?=?49) or to a contingency designed to increase contact with reinforcers (shaping group, n?=?46). For 8 weeks, both groups earned escalating-value vouchers based on thrice-weekly urinalyses: The abstinence group earned vouchers for cocaine-negative urines only; the shaping group earned vouchers for each urine specimen with a 25% or more decrease in cocaine metabolite (first 3 weeks) and then for negative urines only (last 5 weeks). Cocaine use was lower in the shaping group, but only in the last 5 weeks, when the response requirement was identical. Thus, the shaping contingency appeared to better prepare patients for abstinence. A 2nd phase of the study showed that abstinence induced by escalating-value vouchers can be maintained by a nonescalating schedule, suggesting that contingency management can be practical as a maintenance treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
There is currently a stark therapeutic void in the treatment of evolving stroke. Although P-selectin is rapidly expressed by hypoxic endothelial cells in vitro, the functional significance of P-selectin expression in stroke remains unexplored. In order to identify the pathophysiological consequences of P-selectin expression and to identify P-selectin blockade as a potential new approach for the treatment of stroke, experiments were performed using a murine model of focal cerebral ischemia and reperfusion. Early P-selectin expression in the postischemic cerebral cortex was demonstrated by the specific accumulation of radiolabeled anti-murine P-selectin IgG, with the increased P-selectin expression localized to the ipsilateral cerebral microvascular endothelial cells by immunohistochemistry. In experiments designed to test the functional significance of increased P-selectin expression in stroke, neutrophil accumulation in the ischemic cortex of mice expressing the P-selectin gene (PS +/+) was demonstrated to be significantly greater than that in homozygous P-selectin-null mice (PS -/-). Reduced neutrophil influx was accompanied by greater postischemic cerebral reflow (measured by laser Doppler) in the PS -/- mice. In addition, PS -/- mice demonstrated smaller infarct volumes (5-fold reduction, P<.05) and improved survival compared with PS +/+ mice (88% versus 44%, P<.05). Functional blockade of P-selectin in PS +/+ mice using a monoclonal antibody directed against murine P-selectin also improved early reflow and stroke outcome compared with control mice, with reduced cerebral infarction volumes noted even when the blocking antibody was administered after occlusion of the middle cerebral artery. These data are the first to demonstrate a pathophysiological role for P-selectin in stroke and suggest that P-selectin blockade may represent a new therapeutic target in the treatment of stroke.  相似文献   
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