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81.
This report describes a case of unresectable primary gastrointestinal stromal tumour (GIST) treated with imatinib on a neoadjuvant basis, before subsequent successful surgical resection. After six months of imatinib, computed tomography and positron emission tomography imaging demonstrated a significant size reduction and complete metabolic response to treatment, rendering the tumour resectable. Mutational analysis showed an activating KIT mutation in exon 11. The pathological appearance of the resected tumour was heterogeneous with extensive necrosis, cystic and myxoid change, extensive hypocellularity, and patchy foci of residual viable tumour. The implications for this management option of radiological, pathological, and molecular assessment are discussed.  相似文献   
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A total of 151 unselected malignant and nonmalignant lymphoid tissue samples were surveyed by Southern blotting for the presence of Epstein-Barr virus (EBV) DNA. Eight of 28 Hodgkin's disease (HD) samples (29%) had detectable EBV DNA. Both nodular sclerosis and mixed cellularity histologic results were positive. The tumor type with the next highest frequency, 8%, was diffuse large cell lymphoma. The presence of EBV DNA in some HD biopsies suggests that EBV may be a factor in the pathogenesis of this disease. Alternatively, its presence may be secondary to the immune deficiency characteristic of HD. The clonal B-lymphocyte expansions reported in some cases of HD may result from EBV infection.  相似文献   
85.
The present study further examined the in vitro response of human mononuclear cells (MNC) to theSarcocystis gigantea lectin (SGL). The results confirm our previous report that SGL is mitogenic for human MNC. We now report that SGL is not only a potent mitogen but also a polyclonal activator for human peripheral B cells. As was true for pokeweed mitogen (PWM, 2 g/ml), the addition of SGL (25 g protein/ml) to cultures of MNC caused lymphocyte proliferation and B-cell maturation, indicated by a marked increase in IgG and IgM production. As measured by the [3H]-thymidine incorporation assay, SGL induced significantly higher proliferative responses than PWM (P<0.01,n=24). The values obtained by SGL and PWM for IgG and IgM synthesis were essentially identical. As opposed to SGL, the sarcotoxin-containing fraction (SGTF) did not induce antibody formation or proliferative responses in human MNC.  相似文献   
86.
The persistence of Bordetella pertussis and B. parapertussis within vaccinated populations and the reemergence of associated disease highlight the need to better understand protective immunity. The present study examined host immunity to bordetellae and addressed potential concerns about the mouse model by using a comparative approach including the closely related mouse pathogen B. bronchiseptica. As previously observed with B. pertussis, all three organisms persisted throughout the respiratory tracts of B-cell-deficient mice, indicating that B cells are required for bacterial clearance. However, adoptively transferred antibodies rapidly cleared B. bronchiseptica but not human pathogens. These results obtained with the mouse model are consistent with human clinical observations, including the lack of correlation between antibody titers and protection, as well as the limited efficacy of intravenous immunoglobulin treatments against human disease. Together, this evidence suggests that the mouse model accurately reflects substantial differences between immunities to these organisms. Although both B. pertussis and B. parapertussis are more closely related to B. bronchiseptica than they are to each other, they share the ability to resist rapid clearance from the lower respiratory tract by adoptively transferred antibodies, an adaptation that correlates with their emergence as human pathogens that circulate within vaccinated populations.  相似文献   
87.
Previous studies have demonstrated that morphine inhibits the display of maternal behavior in lactating rats. Whether morphine exerts its actions specifically at the mu receptor has not yet been determined. The present study examined this possibility by evaluating whether naloxonazine, an irreversible and selective antagonist of the mu 1 opioid receptor subtype, is able to attenuate morphine's disruptive effect on maternal behavior in primiparous lactating rats. Experiment 1 compared the ability of naloxonazine (AZINE) and naloxone (NAL) to block the action of morphine (MOR) on maternal care. Virgin, Sprague-Dawley rats were mated in our colony and on day 3 postpartum (parturition, day 0) all rats received jugular catheters. On day 6 the mothers received one of the following treatments: MOR alone (10 mg/kg, SC, N = 10); MOR (10 mg/kg, SC) 24 hr after AZINE pretreatment (10 mg/kg, IV, N = 10); MOR (10 mg/kg, SC) 24 hr after NAL pretreatment (10 mg/kg, IV, N = 8); or MOR (10 mg/kg, SC) immediately after NAL (0.5 mg/kg, SC, N = 10). MOR alone completely disrupted maternal behavior (0% responded) which was blocked by prior NAL administration (100%). AZINE pretreatment 24 hr earlier partially blocked MOR disruption of MB (40% responded; significantly different from MOR alone). The response of rats pretreated 24 hr earlier with NAL did not differ from MOR alone. AZINE blocked MOR's effect on pup retrieval to an even greater degree (70% responded vs. 10% in MOR alone). Experiment 2 determined the ability of AZINE to interfere with varying doses of MOR on maternal behavior.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
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Between 1978 and 1984, we examined and performed arthroscopy on 1000 consecutive patients. Ninety-eight of the 1000 had isolated ACL damage. These cases do not include patients with initial ACL injuries combined with other intraarticular damage. Diagnosis was by physical and arthroscopic examination. Examination took place an average 13.6 months after injury. Of the 98 isolated ACL injuries, 56 were complete ruptures and 42 were partial ruptures. In most cases of partial rupture, the clinical diagnosis was wrong. "Meniscal damage" was the usual diagnosis in these cases; the true diagnosis was made only by arthroscopic examination. Thirty-four of the 98 patients with isolated ACL injuries (30 men and 4 women) developed further intraarticular damage. Of these 34, 20 had complete ACL rupture and 14 had partial ACL rupture. Treatment after primary injury included physiotherapy in all patients and bracing in those whose knee was unstable during daily activities. Reconstructive surgical procedures were not performed in those patients. The time lapse from the primary to the secondary injury varied from 1 month to 20 years, with an average of 28 months. The secondary damage was caused by a secondary injury that was mild (22 cases) or developed insidiously (12 cases). Five types of secondary damage were observed: partial ACL tears that became complete--11 cases; meniscal tear--8 cases; loosening and subluxation of the anterior horn of the medial meniscus--14 cases; and fracture or damage to the articular condylar cartilage, with or without bone involvement--11 cases. It should be emphasized that the secondary damages were at times combined.  相似文献   
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