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排序方式: 共有461条查询结果,搜索用时 18 毫秒
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Ig heavy chain variable region (VH) genes expressed by human diffuse large-cell lymphoma (DLC) and follicular lymphoma (FL) were identified and analyzed with respect to germline gene families. In 67 cases of FL, VH region genes were expressed in a pattern similar to that of normal B cells, with a predominance of the large VH3 gene family being used. In contrast, of the 17 cases of DLC, there was an extremely biased use of VH genes. Of these DLC tumors, 88% expressed genes from the small VH4 gene family; and even among these tumors, there was a limited use of genes, with 11 cases producing Igs derived from the VH4.21 germline gene. Although most of the VH genes expressed by DLC tumor cells contained mutations with respect to their germline counterparts, almost all of these mutations occurred before the clonal expansion of the tumor. This contrasts with our previous findings of ongoing mutations in FL and represents a fundamental difference between these two malignancies. This preferential gene use implies an important role for the VH4 gene family, and specifically for VH4.21, in the genesis of DLC. 相似文献
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BD Heckman KA Holroyd G Tietjen FJ O'Donnell L Himawan C Utley R Watakakosol & M Stillman 《Cephalalgia : an international journal of headache》2009,29(6):650-661
This study sought to determine if Whites and African-Americans respond similarly to headache treatment administered in 'real-world' headache specialty treatment clinics. Using a naturalistic, longitudinal design, 284 patients receiving treatment for headache disorders completed 30-day daily diaries that assessed headache frequency and severity at pretreatment and 6-month follow-up and also provided data on their headache disability and quality of life at pretreatment and 1-, 2- and 6-month follow-up. Controlling for socioeconomic status and psychiatric comorbidity, hierarchical linear models found that African-Americans and Whites reported significant reductions in headache frequency and disability and improvements in life quality over the 6-month treatment period. African-Americans, unlike Whites, also reported significant decreases in headache severity. Nevertheless, Africans-Americans had significantly more frequent and disabling headaches and lower quality of life after treatment relative to Whites. Although Whites and African Americans responded favourably to headache treatments, more efficacious treatments are needed given the elevated level of headache frequency that remained in both racial groups following treatment. 相似文献
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Brod SA Lindsey JW Vriesendorp FS Ahn C Henninger E Narayana PA Wolinsky JS 《Neurology》2001,57(5):845-852
OBJECTIVE: To investigate whether ingested human recombinant interferon-alpha2a (IFN-alpha2a) was safe and whether treatment reduces the number of gadolinium-enhanced lesions on serial MRI in patients with active relapsing-remitting MS (RRMS). METHODS: Entry criteria included clinically definite RRMS and one or more gadolinium-enhanced lesions on a screening MRI. RESULTS: Of 80 patients screened, 33 were eligible and 30 patients were enrolled for treatment. Patients were randomized (10 per group) to placebo, 10,000 or 30,000 IU IFN-alpha2a ingested on alternate days for 9 months. They were examined clinically and with monthly cerebral MRI. Sample size projections were based on the assumption of a parenteral IFN-like effect, a 90% reduction of enhancing lesions evident within 1 month of the initiation of treatment in the active treatment groups sustained during the 9-month study as the primary outcome variable. RESULTS: There was no significant effect on enhancing lesions. However, post hoc analysis suggested a possible treatment effect in the 10,000 IU group. By direct monthly comparison of placebo and 10,000 IU group in treatment month 5, there were 73% (p < 0.05) fewer enhancements in the 10,000 IU group than in the placebo group. There was a decrease of tumor necrosis factor-alpha protein secretion at months 4 and 5. Relapses and adverse events were not different among the treatment groups. Ingested IFN-alpha2a did not induce systemic anti-IFN-alpha antibodies. CONCLUSIONS: This trial showed no benefit based on the primary outcome measure. Because changes were detected in immune response and post hoc analysis suggested that a smaller dose could have an effect, IFN-alpha may deserve further study. 相似文献
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Vallbracht C; Liermann DD; Prignitz I; Beinborn W; Roth FJ; Kollath J; Landgraf H; Kaltenbach M 《Radiology》1989,172(2):327-330
Between December 1986 and October 1988, 83 patients with chronic peripheral artery occlusions were treated with a new technique. In 56 patients, the superficial femoral artery was completely occluded; in 21 patients, the popliteal artery; and in six patients, the iliac artery. The length of occlusion ranged from 5 to 35 cm (mean, 12.5 cm). The duration, estimated by history, was 5-48 months (mean, 16.5 months). In seven patients, durations of 6-36 months were documented angiographically. A flexible, blunt, motor-driven rotating catheter was introduced through an 8-F sheath, and rotational angioplasty was performed at low speed (up to 200 rpm). In 49 of 60 (82%) patients in whom this new technique was used as the primary intervention, the occlusions were successfully reopened. In 23 patients in whom conventional methods had failed more than 4 weeks earlier, the success rate for rotational angioplasty was 67% (12 of 18 patients); when the time interval was less than 4 weeks, only one of five patients was treated successfully. In none of the 83 patients did a perforation occur. This new technique can reopen chronic artery occlusions with a high degree of success and without the danger of vessel-wall perforation, even after failure of conventional techniques. 相似文献
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FJ Weir A Smith P Littleton N Carter PA Hamilton 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(9):672-675
The aim of this study was to measure plasma atrial natriuretic peptide in preterm infants with a patent ductus arteriosus before and after closure with indomethacin. Atrial natriuretic peptide was measured in 28 preterm infants with clinical and echocardiographic evidence of a patent ductus arteriosus and in eight preterm infants who did not develop clinical evidence of a patent ductus arteriosus. Plasma concentration of atrial natriuretic peptide was measured by radioimmunoassay. In 18 infants the patent ductus arteriosus closed after one course of indomethacin; atrial natriuretic peptide levels decreased from median 1240 pg/ml (range 201-5483 pg/ml) to 266 pg/ml (range 62-1108 pg/ml). In four infants the patent ductus arteriosus closed after two courses of indomethacin and two infants had surgical ligation after indomethacin treatment failed. The patent ductus arteriosus closed spontaneously in four infants (atrial natriuretic peptide median level 152 pg/ml, range 61-495 pg/ml). In the eight infants without patent ductus arteriosus, atrial natriuretic peptide level was median 224 pg/ml (range 38-876 pg/ml). Measurement of plasma atrial natriuretic peptide concentration has a role in predicting when indomethacin treatment is indicated. 相似文献
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