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61.
Because patients with ulcerative colitis have an increased long-term risk of colorectal cancer, colonoscopic surveillance with multiple biopsies is commonly performed for histopathological detection of dysplasia to select high-risk patients for prophylactic colectomy. Improved differentiation between neoplastic vs. nonneoplastic changes is needed because active inflammation may cause significant misinterpretation of nonneoplastic reactive/regenerative changes in the epithelium. We investigated whether the expression of proliferative antigens is correlated with various degrees of epithelial dysplasia and inflammatory changes in biopsy specimens from patients with long-standing ulcerative colitis. Colorectal biopsy specimens from patients undergoing colonoscopic surveillance were analyzed immunohistochemically using two types of monoclonal antibodies: MIB-1 against Ki-67 and NCL-PCNA against proliferating cell nuclear antigen for structural, active inflammatory, and dysplastic changes. Specimens from patients without inflammatory bowel disease or neoplasia were used as controls; these showed no increased proliferation. However, increased staining with the MIB-1 monoclonal antibody was detected in 9% of the specimens from patients with long-standing ulcerative colitis without active inflammation or dysplasia; this was significantly more common in specimens indefinite for dysplasia, probably positive (24%), and in those with definite dysplasia of low (47%) or high grade (67%; P = 0.008). For increased PCNA staining, there was a nonsignificant correlation (P = 0.30) with increasing degrees of dysplasia. Increased MIB-1 immunostaining was found in 50% and increased PCNA immunostaining in 75% of the specimens displaying mild inflammation. Both antibodies had a 100% increased staining in specimens with moderate or severe inflammation. Increased proliferation as expressed by MIB-1 is thus better correlated with increasing degree of dysplasia than is PCNA. Neither staining method is able to differentiate neoplastic from inflammatory epithelial changes. However, in the absence of active inflammation, immunostaining for MIB-1 may be a valuable adjunct in the confirmation of dysplastic epithelial changes in long-standing ulcerative colitis, particularly in the indefinite changes category. Accepted: 26 February 1999  相似文献   
62.
PURPOSE: The aim of the study was to evaluate the results of percutaneous transluminal angioplasty (PTA) of femoropopliteal arteries in patients with subcritical or critical lower limb ischemia.Materials and Methods: Ninety-two patients underwent 121 PTA procedures, 68 were of the superficial femoral artery (SFA), 13 of the popliteal and 40 of both arteries. Fifty-seven procedures were performed for treatment of occlusions. Eighty-four patients (94 procedures) were monitored with duplex scanning. RESULTS: Technical success rate was 88%. Primary success rates at 12 and 60 months in the whole series were 40% and 27%, respectively. The primary success rate in limbs with SFA occlusion of longer than 5 cm was only 12% after 5 years compared with 32% if the occlusion was 相似文献   
63.
A 41-year-old female with a history of total ulcerative colitis for 15 years is presented. After eight years, she was enrolled in a colonoscopic surveillance program with regular examinations every second year and with biopsy sampling for histologic assessment of dysplasia as well as for flow cytometric analysis. Neither dysplasia nor DNA aneupoloidy developed during the course of the follow-up, but, after seven years, the patient developed a rapidly growing malignant stricture in the lower rectum. At the time of diagnosis, a local gluteal metastasis was found. Following preoperative radiation therapy, laparotomy disclosed a rectal cancer with local growth in the pelvis. Despite an attempt to perform curative surgery, the patient deteriorated and died within four months after the diagnosis. The carcinoma was of a poorly differentiated, mucinous, signet ring cell type, and DNA analyses of both the tumor and its metastases were diploid. Retrospective analyses of mucin content in colonoscopic biopsies showed a gradual shift from sulfated mucin to sialomucin. This case underlines the fact that even rigorous follow-ups offer no absolute guarantee against incurable malignancy in surveillance programs for ulcerative colitis despite the inclusion of DNA analyses.  相似文献   
64.
The effects of dopamine-depleting 6-OHDA infusions in the ventral or dorsal striatum on maternal and sexual behaviors were examined in female rats. Like sham-operated controls, lactating rats receiving 6-OHDA in the ventral striatum built good nests, nursed the infants and showed maternal aggression toward strange intruders. By contrast, the lesioned females performed poorly in tests for pup retrieval, as reflected in greatly protracted retrieval latencies. There was no effect of ventral striatal DA depletions on proceptive and receptive elements of female sexual behavior, which was studied after lactation following ovariectomy and exogenous administration of ovarian hormones, but these animals did show an attenuated hyperactivity response to a low dose of amphetamine. Females with dopamine lesions in the dorsal striatum did not differ from controls with respect to maternal and sexual behavior, but they did show an enhanced hyperactivity response to amphetamine treatment.  相似文献   
65.
R Lfberg  T Caspersson  B Tribukait    A Ost 《Gut》1989,30(12):1731-1736
In seven patients with longstanding ulcerative colitis, multiple mucosal biopsies taken at colonoscopy were assessed for DNA content and histological dysplasia. DNA analyses were performed using flow cytometric analyses in biopsies and microspectrophotometry in imprint slides prepared from the biopsies. Abnormal aneuploid DNA content was detected in five of the patients in eight separate locations in the colon. There was good conformity between the two methods in the detection of aneuploidy. Both methods of DNA analysis are considered to be applicable in mucosal biopsies from patients with ulcerative colitis. In two patients with significant low grade dysplasia in association with macroscopical lesions (DALMs), there was a relationship with aneuploid DNA pattern found by flow cytometric or microspectrophotometric analyses. Indefinite changes, probably dysplastic were found in three other patients and two of those also displayed aneuploidy, although only once in the same biopsy location. In five locations aneuploidy was detected without concomitant dysplasia. DNA-aneuploidy seems therefore to appear earlier than dysplasia and may be an early marker of malignant transformation of the mucosa in ulcerative colitis. Prospective trials are needed before the clinical significance of early findings of aneuploidy can be determined.  相似文献   
66.
Low molecular weight heparin as adjuvant therapy in active ulcerative colitis   总被引:13,自引:0,他引:13  
BACKGROUND: Heparin given intravenously has shown beneficial effects in the treatment of refractory ulcerative colitis in open trials. Low molecular weight heparin (LMWH) offers advantages in the method of administration but have not been evaluated in inflammatory bowel disease conditions. AIM: To assess the tolerability and safety of subcutaneous self-administered LMWH in outpatients with refractory ulcerative colitis and to evaluate any potential adjuvant therapeutic effect. PATIENTS AND METHODS: Twelve patients with mild to moderately active ulcerative colitis were included in the trial. The patients had either responded poorly to treatment with conventional therapy, including oral and/or rectal glucocorticosteroids, or had experienced a rapid relapse during or shortly after GCS therapy. Dalteparin sodium 5000 units s.c. injection was administered twice daily for 12 weeks. Patients were monitored for possible adverse events and changes in clinical symptoms, and endoscopic and histological scores were analysed. Leucocyte scanning was performed at inclusion and at the end of the study. RESULTS: Tolerability and compliance were excellent and no serious adverse events occurred. Eleven patients improved symptomatically and six (50%) attained complete remission after 12 weeks of treatment. Endoscopic, scintigraphic and histological scores were found to be significantly improved. CONCLUSION: Self-administered LMWH given s.c. may be a safe adjuvant therapy for patients with active, glucocorticosteroids-refractory ulcerative colitis. A controlled trial should be undertaken to confirm the positive effects found in this study.  相似文献   
67.
B L?fberg  H Tj?lve 《Cancer letters》1986,31(2):153-161
Whole-body autoradiography with 14C-labelled N-nitrosodibutylamine (NDBA) in pregnant Syrian golden hamsters on day 15 of gestation showed an uptake of radioactivity in the fetuses and a localization of metabolites in the tracheobronchial and nasal mucosa. Experiments in vitro showed a considerable capacity of these tissues of 15-day-old fetuses to form 14CO2 and tissue-bound 14C from the 14C-labelled NDBA, whereas in 12-day-old fetuses these transformations were insignificant. In infant hamsters (4-20 days old) the 14CO2-formation and the 14C-tissue-binding in the respiratory tissues were marked and in some instances even higher than in the tissues of adult animals. In hamsters the respiratory tissues are targets of transplacental carcinogenesis by NDBA and these tissues of the progeny may also undergo malignant transformations when the mothers are given NDBA during nursing. Our results indicate that a local bio-activation of the NDBA will occur in the respiratory tissues of fetuses at late gestation and in these tissues of infants and that this can be correlated to the carcinogenic effects.  相似文献   
68.
Seven fetuses at risk of developing a serious inherited skin disorder (epidermolysis bullosa atrophicans generalisata gravis in 4, bullous ichthyosiform erythroderma in 2, and non-bullous ichthyosiform erythroderma in 1) were subjected to prenatal diagnosis by fetal skin sampling. The conventional "blind" biopsy procedure was used in the first 3 cases; a two-cannula technique (one cannula for the optic instrument and the other for the biopsy forceps) that permits biopsy of the skin under direct vision, was employed in the remaining 4 cases. With the "blind" technique, 8 to 10 biopsy specimens had to be taken to ensure that enough skin material would be available for the microscopic examination; only one specimen out of every two was found to consist of skin; the remainder comprised fetal membranes, myometrium, or tro-phoblast. In one case where the "blind" procedure had been used, leakage of amniotic fluid occurred and labor started in the 33rd week. With the two-cannula technique, the number of biopsy samples could be confined to two or three, and all proved to be of skin.  相似文献   
69.
70.
A decision-analytic model was designed to estimate the associated costs and outcomes of maintenance therapy for Crohn's disease with budesonide controlled ileal release (CIR) capsules (Entocort((R)) capsules, Astra Draco, Lund, Sweden) versus no maintenance therapy. A third-party payer perspective was adopted to compare the direct costs associated with the medication and healthcare resource use for each therapy over a period of 12 four-week cycles. The costs of routine patient care and the consequences of failure, in terms of relapses, acute therapies, hospitalisations and surgery, were included. The outcome was measured as the average number of days in remission per patient per 12-cycle period. Based on the assumptions in the model, the results show that budesonide CIR capsules are associated with a reduction of 16.6 (26%) days in relapse, i.e. a 6% increase in days in remission, over a one-year period compared with no maintenance therapy. Direct healthcare costs are increased by 6% or Swedish kronor (SEK) 1673 ($US1 ~ SEK7.60). Overall, the model shows that there are substantial (non-drug associated) cost offsets from using budesonide CIR capsules as maintenance therapy in Crohn's disease. These cost offsets, in addition to improvements in patients' well-being and quality of life, indicate that maintenance therapy is cost effective compared with no maintenance therapy. The cost per added day in remission is relatively modest (SEK101 ~ $US13). If indirect costs are added to the calculation, it is realistic to argue that a net saving to society would be most likely.  相似文献   
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