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A Hodgkin cell-specific antigen is expressed on a subset of auto- and alloactivated T (helper) lymphoblasts 总被引:21,自引:0,他引:21
A Hodgkin cell-specific antigen detected by the monoclonal antibody Ki- 1 was found on T helper lymphocytes after activation by autologous and allogeneic stimulator cells. About 50% of lymphoblasts generated by auto- and alloactivation reacted with the antibody. In contrast, only less than 6% of lymphoblasts stimulated with Con-A, phytohemagglutinin (PHA), or protein A, and none of lymphoblasts activated by oxidative mitogenesis, expressed this antigen. Among several permanent cell lines tested, the K562, MOLT-4, HL-60, and EBV transformed B lymphoblastoid cells reacted with the Ki-1 antibody. The results may indicate possible relationships between the autoreactive subset of T lymphocytes and the pathogenesis of Hodgkin's disease. 相似文献
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Varma A Gunn J Gardiner A Lindow SW Duthie GS 《Diseases of the colon and rectum》1999,42(12):1537-1543
PURPOSE: An obstetrically damaged anal sphincter is the principal cause of the development of fecal incontinence in otherwise healthy females. Reports suggest that such damage complicates as many as 35 percent of primiparous vaginal deliveries, with 13 percent of first-time mothers becoming symptomatic. In maternity units delivering 3,000 patients annually, it would follow that 390 symptomatic patients would develop new symptoms each year. This incidence of dysfunction does not reflect current clinical practice. We have investigated this discrepancy to establish the actual incidence of anal sphincter trauma associated with childbirth. METHODS: During a six-week period, 159 females (105 primiparous and 54 para-I) were prospectively assessed postnatally using a standardized symptom questionnaire, endoanal ultrasound, and anal manometry. This group constituted 84 percent of all eligible deliveries occurring in the unit during the study period. RESULTS: One patient developed fecal urgency after this delivery; there were no reports of fecal incontinence. Anal sphincter injuries were identified ultrasonically in 6.8 percent of primiparous patients, 12.2 percent of para-I patients having vaginal deliveries, and 83 percent of patients having forceps deliveries overall. Manometric data provided confirmatory evidence, with significantly reduced maximum squeeze pressures in patients with a disrupted anal sphincter (P<0.0005). CONCLUSIONS: A symptom questionnaire is inadequate to identify anal sphincter injuries. The incidence of sphincter injury in relation to vaginal delivery has been overestimated in previous published work. This study demonstrates that the true incidence is 8.7 percent overall and that symptoms of sphincter dysfunction are uncommon this is in keeping with current clinical practice. 相似文献
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Tang SJ Gordon ML Yang VX Faughnan ME Cirocco M Qi B Yue ES Gardiner G Haber GB Kandel G Kortan P Vitkin A Wilson BC Marcon NE 《Gastrointestinal endoscopy》2003,58(4):591-598
BACKGROUND: Hereditary hemorrhagic telangiectasia is characterized by mucocutaneous telangiectases and visceral arteriovenous malformations. Knowledge is limited concerning the development hemodynamics of mucocutaneous telangiectases. Doppler optical coherence tomography can demonstrate microvascular blood flow at flow rates as low as 20 microm/second, which is up to approximately 100 times more sensitive than Doppler US. The aims of this study were to collect in vivo Doppler optical coherence tomography images of mucocutaneous telangiectases and normal surrounding mucosa and skin, and to gain experience for an in vivo GI endoscopic study. It was hypothesized that visibly normal areas may have occult telangiectases and that mucocutaneous telangiectases that have bled may have a higher rate of blood flow than mucocutaneous telangiectases with no history of bleeding. METHODS: Twelve patients with hereditary hemorrhagic telangiectasia and mucocutaneous telangiectases were studied. Two to 3 visible mucocutaneous telangiectases on the digits, lips, and tongue were imaged with Doppler optical coherence tomography, along with visually normal surrounding areas at each site. The Doppler optical coherence tomography images were obtained in 0.5 second by using 1310 nm light. RESULTS: A total of 67 mucocutaneous telangiectases from the 12 patients were imaged (38 digit, 16 lip, 13 tongue). Blood flow was demonstrated within every mucocutaneous telangiectasis imaged. Doppler optical coherence tomography did not identify any abnormal vasculature within visually normal areas. Mucocutaneous telangiectases with a history of bleeding (n = 18) were situated closer to the surface, compared with mucocutaneous telangiectases with no bleeding history (n = 49), but there was no difference in the Doppler flow appearance. CONCLUSIONS: Visually normal areas in patients with hereditary hemorrhagic telangiectasia did not appear to have abnormal vasculature. Mucocutaneous telangiectases with a history of bleeding were more superficial but were otherwise similar to mucocutaneous telangiectases with no bleeding history. 相似文献