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排序方式: 共有974条查询结果,搜索用时 15 毫秒
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Plasmid-Determined AmpC-Type β-Lactamases 总被引:26,自引:0,他引:26
5.
Howard B. Yeon Jacob Weinberg Vincent Arlet Jean A. Ouelett Kirkham B. Wood 《European spine journal》2007,16(9):1379-1385
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4. 相似文献
6.
Ralstonia paucula (Formerly CDC group IV c-2): unsuccessful strain differentiation with PCR-based methods, study of the 16S-23S spacer of the rRNA operon, and comparison with other Ralstonia species (R. eutropha, R. pickettii, R. gilardii, and R. solanacearum) 下载免费PDF全文
Moissenet D Bidet P Garbarg-Chenon A Arlet G Vu-Thien H 《Journal of clinical microbiology》2001,39(1):381-384
Ralstonia paucula (formerly CDC group IV c-2) can cause serious human infections. Confronted in 1995 with five cases of nosocomial bacteremia, we found that pulsed-field gel electrophoresis could not distinguish between the isolates and that randomly amplified polymorphic DNA analysis was poorly discriminatory. In this study, we used PCR-ribotyping and PCR-restriction fragment length polymorphism analysis of the spacer 16S-23S ribosomal DNA (rDNA); both methods were unable to differentiate R. paucula isolates. Eighteen strains belonging to other Ralstonia species (one R. eutropha strain, six R. pickettii strains, three R. solanacearum strains, and eight R. gilardii strains) were also tested by PCR-ribotyping, which failed to distinguish between the four species. The 16S-23S rDNA intergenic spacer of R. paucula contains the tRNA(Ile) and tRNA(Ala) genes, which are identical to genes described for R. pickettii and R. solanacearum. 相似文献
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Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma 总被引:3,自引:4,他引:3
Botchan A; Hauser R; Gamzu R; Yogev L; Lessing JB; Paz G; Yavetz H 《Human reproduction (Oxford, England)》1997,12(1):73-76
The study was conducted to determine the deleterious effect of lymphoma
disease on spermatogenesis and to evaluate the possibility that the disease
is mediated primarily by inherent mechanisms in Hodgkin's disease and
non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma
disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation
prior to adjuvant treatments. A comparison was made of pre- and post-thaw
sperm quality between lymphoma patients and healthy volunteers who applied
for sperm donation. This was followed by further assessment of the
differences between patients with Hodgkin's disease and non-Hodgkin's
lymphoma in terms of sperm variables, clinical parameters and blood hormone
concentrations. It was found that patients with lymphoma disease had
significantly impaired pre-freeze and post-thaw sperm quality compared with
that of healthy volunteers. Patients with non-Hodgkin's lymphoma had
spermatozoa of higher quality than patients with Hodgkin's disease. No
differences were found in the clinical or hormonal parameters between these
two groups. As expected, reduced testicular size and abnormal testicular
consistency were correlated with decreased sperm quality. The mere presence
of cancer disease has a direct negative effect on spermatogenesis, which is
probably not related to incidental side-effects. A variable degree of
impairment should be expected with different categories of cancer.
相似文献
10.
A. Philippon G. Arlet P. H. Lagrange 《European journal of clinical microbiology & infectious diseases》1994,13(1):S17-S29
Resistance to oxyimino cephalosporins was originally highlighted by the emergence of plasmid-encoded extended-spectrum β-lactamases deriving by mutation from TEM-1, TEM-2 and SHV type enzymes (class A). The broader spectrum of resistance produced by these enzymes is related to more amino acid substitutions, but susceptibility to seven alpha-methoxyimino cephalosporins and carbapenems was preserved until recently. Clavulanate-sensitive extended-spectrum β-lactamases are distributed worldwide, mainly amongKlebsiella pneumoniae isolates. Novel clavulanate-sensitive extended-spectrum β-lactamases deriving from other class A enzymes (e.g. MEN-1 from βlaOXY, OXA-11 inPseudomonas aeruginosa from PSE-2) have been reported. Recently, clavulanate-resistant extended-spectrum β-lactamases (class C) were encountered amongst single isolates, mostlyKlebsiella pneumoniae. These cephalosporinases or cefamycinases (usually chromosomally mediated) have expanded the spectrum of plasmid-encoded resistance to include seven alpha-methoxyimino cephalosporins. Thus far, only two isolates (1Pseudomonas aeruginosa, 1Bacteroides fragilis), both recovered in Japan, with plasmid-mediated resistance to carbapenems have been found. 相似文献