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Continence following the gracilis stimulated neosphincter reconstruction after total rectal excision is inferior to that obtained in the presence of an intact anal canal. We describe a modification of the alpha loop in which the tendon is brought through the belly of the gracilis muscle. The results in three patients are presented.
Résumé La reconstruction sphinctérienne après excision totale du rectum au moyen d'un néosphincter fait d'un muscle gracilis stimulé donne des résultats sur le plan de la continence inférieurs à ceux obtenus en présence d'un canal anal intact. Nous décrivons une modification de l'anse alpha dans laquelle le tendon est fixé après avoir traversé la sangle de muscle gracilis. Les résultats de trois patients sont rapportés.
  相似文献   
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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   
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J Feil  C Burri  H Kiefer 《Der Orthop?de》1988,17(3):272-278
Both in open and in closed elbow fractures, anatomical joint reconstruction and rigid internal fixation, which permit early initiation of motion, are essential for good joint function. However, in open distal intraarticular humerus fractures this is more difficult to achieve, owing to the high rate of comminuted types C 2 and C 3 fractures. In addition, the extensive soft tissue lesions often mean that physiotherapy cannot be started until later than would otherwise be desirable. This retrospective study shows that the functional results in 60 patients operated on for correction of open distal intraarticular humerus fractures were worse (1/3 "excellent/good", 2/3 "moderate/poor") than those in patients treated for closed fractures. Complications included superficial infection in 7 patients, osteitis in 11, late instability in 10, fatigue failure of the implants in 5, and non-union in 10 patients.  相似文献   
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Population and evolutionary analyses of pathogenic bacteria are frequently hindered by sampling strategies that concentrate on isolates from patients with invasive disease. This is especially so for the gram-negative diplococcus Neisseria meningitidis, a cause of septicemia and meningitis worldwide. Meningococcal isolate collections almost exclusively comprise organisms originating from patients with invasive meningococcal disease, although this bacterium is a commensal inhabitant of the human nasopharynx and very rarely causes pathological effects. In the present study, molecular biology-based techniques were used to establish the genetic relationships of 156 meningococci isolated from healthy young adults in the Czech Republic during 1993. None of the individuals sampled had known links to patients with invasive disease. Multilocus sequence typing (MLST) showed that the bacterial population was highly diverse, comprising 71 different sequence types (STs) which were assigned to 34 distinct complexes or lineages. Three previously identified hyperinvasive lineages were present: 26 isolates (17%) belonged to the ST-41 complex (lineage 3); 4 (2.6%) belonged to the ST-11 (electrophoretic type [ET-37]) complex, and 1 (0.6%) belonged to the ST-32 (ET-5) complex. The data were consistent with the view that most nucleotide sequence diversity resulted from the reassortment of alleles by horizontal genetic exchange.  相似文献   
8.
We have sequenced and compared DNA from the ends of three human chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub- domains with entirely different patterns of homology to other chromosome ends. The distal regions contain numerous, short (<2 kb) segments of interrupted homology to many other human telomeric regions. The proximal regions show much longer (approximately 10-40 kb) uninterrupted homology to a few chromosome ends. A comparison of all yeast subtelomeric regions indicates that they too are subdivided by degenerate TTAGGG repeats into distal and proximal sub-domains with similarly different patterns of identity to other non-homologous chromosome ends. Sequence comparisons indicate that the distal and proximal sub-domains do not interact with each other and that they interact quite differently with the corresponding regions on other, non- homologous, chromosomes. These findings suggest that the degenerate TTAGGG repeats identify a previously unrecognized, evolutionarily conserved boundary between remarkably different subtelomeric domains.   相似文献   
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Nitric oxide (NO) modulates a variety of processes in the mammalian brain, but the mechanisms of neuronal NO signaling are poorly understood. In the periphery, many effects of NO are mediated via the generation of the second messenger cyclic guanosine-3',5'-monophosphate (cGMP) and activation of the cGMP-dependent protein kinase type I (cGKI). However, previous studies suggested that the expression of cGKI in the nervous system is rather restricted, thus, questioning the functional significance of the cGMP/cGKI pathway as a mediator of NO signaling in the brain. Here we have performed a detailed immunohistochemical study to elucidate the distribution of cGKI in the CNS and eye of the mouse. Expression of cGKI protein was detected not only in the previously described areas (cerebellum, hippocampus, dorsomedial hypothalamus) but also in a number of additional regions, such as medulla, subcommissural organ, cerebral cortex, amygdala, habenulae, various hypothalamic regions, olfactory bulb, pituitary gland, and retina. Immunoblotting with isoform-specific antibodies indicated that the cGKIalpha isoform is prominent in the cerebellum and medulla, whereas the cGKIbeta isoform is predominant in the cortex, hippocampus, hypothalamus, and olfactory bulb. Similar levels of the isoforms were detected in the pituitary gland and eye. Thus, it appears that distinct brain regions express distinct cGKI isoforms that signal via distinct pathways. Together, these results improve our understanding of the cellular and molecular mechanisms of NO/cGMP/cGKI signaling and indicate that the distribution and functional relevance of this pathway in the mammalian brain is broader than previously thought.  相似文献   
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