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1.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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The effects of metoclopramide (MTC) and bromocriptine (BRC) (two drugs which act as antagonist and agonist of DOPA-receptors, respectively) on the zona glomerulosa of dexamethasone/ACTH-treated rats were investigated by coupled biochemical and morphometric techniques. Short-term (1-h) MTC administration significantly increased the plasma concentration of aldosterone, while long-term (7-day) MTC administration, as well as short- and long-term treatment with BRC did not cause any apparent change. Long-term MTC administration was found to significantly potentiate both the rise in the plasma level of aldosterone and the hypertrophy of the zona glomerulosa and its parenchymal cells induced by a prolonged treatment with angiotensin II (AII), but not those evoked by a chronic sodium deprivation alone or combined with AII infusion. Long-term BRC administration notably counteracted the effects of sodium restriction (coupled or not with AII infusion), but not those induced by the administration of AII alone. Long-term MTC administration partially reversed both the lowering of the plasma concentration of aldosterone and the atrophy of the zona glomerulosa and its parenchymal cells caused by a prolonged sodium-loading (combined or not with captopril infusion), but not those produced by the administration of captopril alone. On the other hand, long-term BRC treatment induced a further significant reduction in the blood level of aldosterone and the volume of zona glomerulosa and its cells only in captopril-treated animals. These findings are consistent with the view that the dopaminergic system exerts a maximal tonic inhibitory effect not only on the secretory activity, but also on the growth and steroidogenic capacity of the rat zona glomerulosa. Furthermore, they suggest that the activity of the dopaminergic system is in turn controlled by the sodium balance, being almost completely suppressed by a prolonged sodium deprivation.  相似文献   
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The aim of the study was to evaluate the effectiveness of transabdominal wedge colpectomy as surgical treatment for cystocele. One hundred and sixty-three women with either first or second-degree cystocele (Beecham classification), rectocele and concomitant stress urinary incontinence or benign pelvic masses were submitted for a combined operation. Transabdominal repair of the cystocele was performed by wedge colpectomy employing two different absorbable sutures, Vicryl and PDS. The choice of suture was not random but depended on the period at which surgery was performed. Data obtained were analyzed with Student’st-test and Fisher’s exact test. The cystocele cure rate was 90.2% (110 out of 122) at 3-year follow-up and was significantly associated with the preoperative degree, being 95.5% and 76.5% in first and in second degree, respectively (P=0.003). At 1-year follow-up the cure rate was significantly associated with the type of the suture employed (P=0.01). At 2-year follow-up rectocele cure rate was 97.2% and vaginal vault prolapse appeared in 3.5% of cases. Stress urinary incontinence relapsed in 10% of patients after Burch colposuspension. After the operation 94.1% of the women declared normal coitus. In the present series wedge colpectomy was found to be effective in repairing first-degree cystocele, whereas a high incidence of relapse was observed when second-degree cystocele was present preoperatively. The suture material employed influenced the cure rate. EDITORIAL COMMENT: Wedge colpectomy of the anterior vaginal wall has been described by Weinstein and Roberts (1949), Macer (1978) and Drutz (1991) as a means of abdominally correcting anterior vaginal wall relaxation. Although the present authors did not find as high a success rate with the procedure as the previous investigators, they do show that an abdominal approach to cystocele repair is feasible. There are instances when such an approach would be advantageous to avoid repositioning for a vaginal anterior wall repair. The danger of abdominal anterior wedge colpectomy lies in the dissection of the bladder base from the underlying vaginal wall. Dissection in this area must proceed carefully to avoid trauma to the bladder, ureters and, more distally, to the urethrovesical junction. Performed carefully, with attention directed at avoiding these structures, the abdominal wedge colpectomy is a potentially useful procedure to add to the armamentarium of the urogynecologic surgeon.  相似文献   
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A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence.  相似文献   
9.
Competitive control of the self-renewing T cell repertoire   总被引:1,自引:0,他引:1  
We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.   相似文献   
10.
Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by disproportionate short stature and precocious osteoarthritis. Radiographic manifestations include epiphyseal, metaphyseal and vertebral abnormalities. Mutations in the cartilage oligomeric matrix protein (COMP) have been identified to cause PSACH. Most of them affect one of the eight calcium-binding domains of COMP. We describe a clinically and radiologically typical PSACH 4-year-old girl and her 31-year-old father. A novel mutation, 1345-1347CCC deletion in exon 13, of COMP was identified in both patients. The deletion would be expected to result in the loss of the conserved proline at codon 449 from the sixth calcium-binding domain. This result further supports that COMP is the only gene, discovered to date, responsible for PSACH across different populations and that the calcium-binding domains are important to the function of the normal COMP.  相似文献   
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