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51.
52.
Guan  XY; Horsman  D; Zhang  HE; Parsa  NZ; Meltzer  PS; Trent  JM 《Blood》1996,88(4):1418-1422
Deletion of the long arm of chromosome 6 (6q) is one of the most common chromosomal alterations in human B-cell lymphomas. Conventional cytogenetic banding analysis and loss-of-heterozygosity (LOH) studies have detected several common regions of deletion ranging across the entire long arm (6q), with no defined recurrent breakpoint yet identified. We describe here a strategy combining chromosome microdissection and fluorescence in situ hybridization (Micro-FISH) to determine a minimal region of deletion along chromosome 6. Seven clinical cases and one cell line of follicular lymphoma containing a t(14;18) and one case of diffuse lymphoma, also with a t(14;18), were used for this study. All nine cases had previously defined abnormalities of chromosome 6 determined by cytogenetic analysis. The results of chromosome dissection were unexpected and in contrast to the suggestion of disparate breakpoints by conventional chromosome banding. Specifically, Micro-FISH analysis provided evidence for a common breakpoint at 6q11 in seven of nine cases. After Micro-FISH analysis, all of the presumed simple deletions of chromosome 6 were carefully reanalyzed and shown to actually represent either nonreciprocal translocations (three cases), interstitial deletions (five cases), or isochromosome (one case). The recurrent proximal breakpoint (6q11) was detected in seven of nine cases, with the minimal region of deletion encompassing 6q11 to 6q21. By analogy to other tumor systems, the identification of recurring breakpoints within 6q11 may suggest that a gene(s) important to the genesis or progression of follicular lymphoma can be localized to this band region.  相似文献   
53.
BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8)  相似文献   
54.
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive.  相似文献   
55.
Oxidative metabolism of the human eosinophil   总被引:14,自引:1,他引:14  
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.  相似文献   
56.
A retrospective analysis of 127 surgically treated cases of T-1, T-2 carcinoma of oral tongue during the period 1987-1990 was undertaken. 68.5 per cent (87) underwent hemiglossectomy and 31.5 per cent (40) underwent wide excision. There were loco-regional recurrences in 22 per cent (27). In the hemiglossectomy group 9 per cent (8 of 87) had local recurrences compared to 25 per cent (10 of 40) of wide excision group, (P = 0.01). Mean disease free survival was 40 months and 33 months for hemiglossectomy group and wide excision group respectively, (P = 0.006). It is seen that local recurrences are significantly less for the hemiglossectomy group compared to the wide excision group.KEY WORDS: Disease free survival, Early cancer, Recurrence, Surgery, Tongue  相似文献   
57.
大量的动物实验和许多早期临床试验显示放射在冠状动脉再狭窄治疗中的价值。为了建立有效的放射实施技术及合适的病例选择标准,作者进行了这项研究。SCRIPPS试验是一项小样本的双盲法随机研究,病例入组标准是患者冠状动脉再狭窄已置支架或准备置支架;先前病灶处介入间隔>4周;参照血管直径在3~5mm之间,病灶长度≤30mm。将病例随机分成两组:一组后装管内用192Ir源,而另一组为假源。192Ir源的放置取决于病灶的长短。较短的病灶用一长19mm的带状物,该带状物含有5个长3mm的192Ir源,每个源间隔1mm,较长的病灶用含9个192I…  相似文献   
58.
OBJECTIVE: An orally administered antimicrobial regimen for the treatment of group A beta-hemolytic streptococcal (GABHS) pharyngitis given once rather than multiple times each day would be more convenient and might result in improved patient compliance. The purpose of this study was to evaluate the effectiveness of once-daily amoxicillin in the treatment of GABHS pharyngitis. PATIENTS: Children presenting to a private pediatric office with GABHS pharyngitis. DESIGN: Patients were randomly assigned to receive orally either amoxicillin (750 mg once daily) or penicillin V (250 mg three times a day) for 10 days. Compliance was monitored by urine antimicrobial activity. OUTCOMES: Outcomes were measured by impact on the clinical course, eradication of GABHS within 18 to 24 hours, and bacteriologic treatment failure rate as determined by follow-up throat cultures 4 to 6 and 14 to 21 days after completing therapy. GABHS isolates were serotyped to distinguish bacteriologic treatment failures (same serotype as initial throat culture) from new acquisitions (different serotypes). RESULTS: During the 16 months of this study, 152 children between 4 and 18 years of age (mean, 9.9 years) were enrolled; 79 children were randomly assigned to receive once-daily amoxicillin and 73 were assigned to receive penicillin V three times a day. The children in the two treatment groups were comparable with respect to age, duration of illness before initiation of therapy, compliance, and signs and symptoms at presentation. There was no significant difference in the clinical or bacteriologic responses of the patients in the two treatment groups at the 18- to 24-hour follow-up visit. Bacteriologic treatment failures occurred in 4 (5%) of the 79 patients in the amoxicillin group and in 8 (11%) of the 73 patients in the penicillin V group. CONCLUSIONS: These data demonstrate that once-daily amoxicillin therapy is as effective as penicillin V therapy given three times a day for the treatment of GABHS pharyngitis, and if confirmed by additional investigations, once-daily amoxicillin therapy could become an alternative regimen for the treatment of this disease.  相似文献   
59.
60.
Ho  PS; Yu  SW; Sether  LA; Wagner  M; Ho  KC; Haughton  VM 《Radiology》1988,169(1):87-91
Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body.  相似文献   
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