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71.
Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis.  相似文献   
72.
Of 1265 patients admitted to the CCU with the diagnosis of acuteMI, 96 (7.6%) developed ventricular fibrillation within 72 hoursfollowing admission. Of these 96, 35 (36.5%) had secondary VFassociated with left ventricular failure; they had a high in-hospitalmortality of 57.1%. The remaining 61 (63.5%) had primary VF,i.e. VF occurring in the absence of significant LV failure.Fourteen of these (23%) died in hospital: 9 due to PVF (3 duringthe first episode, 6 during a recurrence). This mortality figurewas significantly higher (P<0.001) than the mortality of10% seen among patients who did not experience VF. Primary VFshowed a recurrence rate of 20%. Compared with the 1061 patientswho left the hospital without primary VF, the 61 subjects withthis rhythm disorder were older, had larger infarcts and morefrequent complications, such as pericarditis, conduction abnormalities,frequent ventricular premature contractions and signs of rightventricular failure. These findings, in contrast with a widelyheld view, suggest that primary VFmay carry a guarded prognosis.  相似文献   
73.
Chen  CL; Fuscoe  JC; Liu  Q; Relling  MV 《Blood》1996,88(6):2210-2218
Etoposide is one of the most widely used antineoplastics. Unfortunately, the same treatment schedules associated with impressive efficacy are associated with an increased risk of secondary acute myeloid leukemia (AML), which has prompted its withdrawal from some treatment regimens, thereby potentially compromising efficacy against the original tumor. Because etoposide-associated AML is characterized by site-specific illegitimate DNA recombination, we studied whether etoposide could directly cause site-specific deletions of exons 2 and 3 in the hprt gene. Human lymphoid CCRF-CEM cells were treated with etoposide for 4 hours, and DNA was isolated after subculturing. The deletion of exons 2 and 3 from hprt was assayed by a quantitative polymerase chain reaction (PCR) method. In the absence of etoposide treatment, the frequency of deletions of exons 2 and 3 was very low (5.05 x 10(-8)). After exposure to 10 mumol/ L etoposide, the frequency of the exon 2 + 3 deletion was increased immediately after and at 24 hours after etoposide treatment (65 to 89 x 10(-8)) and increased to higher levels (128 to 173 x 10(-8)) after 2 and 6 days of subculture (P < .001 overall). The frequency of the exon 2 + 3 deletion assessed at 6 days of subculture after 4 hours of 0, 0.25, 1, 2.5, 5, and 10 mumol/L etoposide treatment increased with etoposide concentration, ie, 5.05 x 10(-8), 89.2 x 10(-8), 108 x 10(-8), 142 x 10(-8), 163 x 10(-8), and 173 x 10(-8), respectively (P < .0001). Sequencing of a subset of amplified products confirmed the presence of DNA sequences at the breakpoints consistent with V(D)J recombination. By contrast, exon 2 + 3 deletions after etoposide treatment in the myeloid cell lines KG-1A and K562 showed no evidence of V(D)J recombinase in their genesis. We conclude that etoposide can induce the illegitimate site-specific action of V(D)J recombinase on an unnatural DNA substrate after a single treatment in human lymphoid cells.  相似文献   
74.
Colorectal metastases to the liver: selective chemoembolization   总被引:6,自引:0,他引:6  
Lang  EK; Brown  CL  Jr 《Radiology》1993,189(2):417
  相似文献   
75.
ABSTRACT

Schnitzler syndrome is a rare, auto inflammatory condition known to manifest with bone pain, urticarial rash, fevers, relapsing arthralgia, and fatigue. In this case report, we describe a patient who was diagnosed with Schnitzler Syndrome that had initially presented with a unilateral pressure-type headache with a sensation of a ‘dagger’ stabbing into the back of the eye. He also had an associated ipsilateral redness of the conjunctiva, eyelid swelling, subtle optic disc elevations bilaterally and facial flushing - but with no visual acuity, pupillary, or lacrimatory changes. Anterior segment, fundoscopy, intraocular pressures and extraocular muscle movements were otherwise normal.  相似文献   
76.
77.
Renal allograft loss from chronic rejection or cyclosporine toxicity (CsAT) is characterized by progressive interstitial fibrosis, yet the protein composition of these lesions is unknown. The normal tubular basement membrane (TBM) contains laminin (LM), collagen IV (containing collagen IV alpha chain 1 [COL4A1] and COL4A2), thrombospondin (TSP), and fibronectin (FN). Only TSP and FN extend beyond the TBM into the interstitial space. Very scanty amounts of interstitial collagens (I and III) are detected in the interstitium. In a pilot study of human renal allograft biopsy specimens, three patterns of extracellular matrix (ECM) composition were identified. Pattern 1 showed no change in ECM composition; pattern 2 showed generalized accumulation of collagens I and III in the interstitium; and pattern 3 showed new expression of COL4A3 and LM-beta2 in the proximal TBM. Criteria were established for the clinicopathological diagnosis of CsAT and rejection. These diagnoses were correlated with the ECM composition in 22 renal allograft biopsy specimens. Control groups were examined in a similar manner and included native kidney biopsy specimens from patients with other allografts (n = 7), renal biopsy specimens from patients with glomerular disease (n = 9), and renal allograft biopsy specimens from patients without clinicopathological evidence of renal disease. These data show that rejection is associated with pattern 3 and CsAT is associated with pattern 2. Thus, detection of ECM composition may be a useful adjunct to standard microscopy in distinguishing rejection from CsAT in renal allograft biopsy specimens. These data suggest that interstitial fibrosis associated with rejection and CsAT result from different pathogenic mechanisms.  相似文献   
78.
立位X线胸片可敏感而特异地显示膈下游离气体 ,对开放性结肠直肠切除术后空腔脏器出现破损是一项有效的检查 ,但由于剖腹术后气腹自然吸收所需要的时间未知 ,其作用尚未被确定。本次试验的目的即在于确定这一时间。   3个月内连续 92例接受了连续性结肠直肠切除术的病人 (8例拒绝合作 ,9例采用了腹腔镜技术 )中的 75例参与了这次试验 (平均年龄 6 2 1岁 ,男∶女 =1 3∶1) ,手术指征分别为直肠癌 6例 ,憩室病 2例 ,肠道炎症 2例 ,放疗引起狭窄 3例 ,功能性疾患 (慢性运输性便秘 ,直肠脱垂 ) 2例 ,其它 (家族性腺瘤息肉、乙状结肠扭转、短…  相似文献   
79.
80.
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