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Gastroepiploic veins: CT appearance in pancreatic disease.   总被引:7,自引:0,他引:7  
The frequency with which gastroepiploic vein (GEV) enlargement was seen on CT and its relevance to disease of the portal venous system associated with pancreatic disease were studied. We performed a retrospective study of 50 patients with proved pancreatic disease and another 50 patients without such disease. The CT examinations were done in incremental dynamic fashion after a bolus injection of contrast medium. Scans were evaluated for collateral channel formation, including GEV enlargement, and for involvement of the portal venous system by pancreatic disease. Part of the GEV arcade was visible in 36 patients without pancreatic disease, and on average measured 3.2 mm in diameter (range, 1-5.5 mm). GEV enlargement was visible in 62% of the patients with disease; 16% demonstrated a vessel 6 mm or more in diameter. Thirty-four percent of the patients with disease had portal venous complications: 26% had isolated splenic vein involvement, 2% had isolated portal vein involvement, and 6% had a combination of splenic and portal vein involvement. Of the patients with splenic vein disease, 81% had collateral channel formation, 50% of them demonstrating isolated GEV enlargement. Patients with splenic vein disease due to acute pancreatic disease had a much higher instance of GEV enlargement (83.3%). Collateral vessels are commonly seen on CT scans of patients with splenic vein disease and most often occur via enlarged GEVs. Acute pancreatic disease is frequently associated with GEV enlargement, suggesting that the latter represents an early response to splenic vein disease. In contrast, multiple collateral pathways tend to develop in patients with chronic pancreatic disease.  相似文献   
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To our knowledge, this is the first clinical trial in multiple sclerosis (MS) demonstrating the feasibility of directing immunomodulating therapy by monitoring immunologic results. Cyclophosphamide was administered at monthly intervals, escalating the dose until there was a significant reduction in both the number of blood B lymphocytes and helper/inducer (CD4) T cells of 14 patients with chronic progressive MS. The frequency and severity of adverse effects led us to conclude that the regimen is too toxic for the long-term treatment of patients with MS.  相似文献   
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Among 404 patients with primary tumors of extremity-trunk sites entered in the Intergroup Rhabdomyosarcoma Study (IRS) (1972 to 1984), 154 were placed in clinical group IIa, ie, with negative nodes but with "microscopic residual" (MR) disease, following the initial excisional (not biopsy) procedure. An elective reexcision of the area of the primary tumor (PRE) was performed in 41 of these patients within 35 days (mean interval, 14 days; SE, 0.9) with no intervening therapy. These procedures consisted of wider excision of the tumor "bed," resulting in a technical transfer of these patients from group IIa to group I, ie, complete excision. This reduced intensity of nonsurgical therapy (irradiation and chemotherapy). Among the 41 patients who underwent PRE, the 3-year survival estimate (Kaplan-Meier) was 91% (SE, 4%). This may be compared with the results in 113 patients who remained in group IIa, in which the 3-year survival estimate was 74% (SE, 4%). A second group for comparison consisted of the 73 patients with trunk/extremity tumors who were placed in group I after a single excisional procedure, ie, no PRE, in whom the 3-year survival estimate was 74% (SE, 5%). Recognized prognostic factors influencing survival in these groups were comparable, with the exception of tumor size, ie, the largest tumors (greater than or equal to 10 cm in diameter) were concentrated in groups I and IIa. When patients with tumors greater than or equal to 10 cm in diameter (9.7% of the total) were removed from all three study groups, patients undergoing PRE had longer survival duration estimates than patients in the control groups.  相似文献   
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Spontaneous immunoglobulin (Ig) secretion by cells from multiple sclerosis (MS) patients (in the progressive phase) treated with monthly pulse doses of cyclophosphamide (CY) (1000–1600 mg/M2) was measured using the protein A plaque assay, to evaluate the effect of CY treatment on B-cell function. Surprisingly, an increase, rather than a decrease, in Ig-secreting cells was seen following CY treatment. CY-treated MS patients averaged 1380±535 spontaneous total (IgM+G+A) Ig plaque-forming cells (PFC) per 1×106 peripheral blood mononuclear cells (MNC), measured at 15–22 days after monthly CY administration, while healthy adults had 280±47 Ig PFC/106 MNC, and MS patients not treated with CY had 300±43 Ig PFC/106 MNC. The observed increase was due to an increase in IgG and IgA PFC. PFC levels remained elevated for 4 weeks following CY treatment, decreasing to control levels by 7–8 weeks post-CY. A small increase in serum IgG level was noted after >12 months of pulse CY therapy; no increase was seen in CSF IgG levels. A preferential decrease in the number of CD4+ T cells was also seen in the CY-treated MS patients. We propose that the observed increase in the number of spontaneous Ig PFC was due to the CY-induced disruption of the CD4+ T cell-mediated control ofin vivo activated B cells.  相似文献   
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A novel method for processing respiratory specimens to improve culture and acid-fast staining of mycobacteria is introduced. This new method utilized N,N-dimethyl-N-(n-octadecyl)-N-(3-carboxypropyl)ammonium inner salt (Chemical Abstract Service no. 78195-27-4), also known as C18-carboxypropylbetaine (CB-18). In a blinded, five-center study, CB-18-based processing was compared to the standard method combining NALC and NaOH (NALC/NaOH). A total of 573 respiratory specimens were tested. Individual specimens were split approximately equally; the host institutions processed half of each specimen by the NALC/NaOH method, while the other half was processed with CB-18 at Quest Diagnostics—Baltimore. A total of 106 specimens were culture positive for acid-fast bacilli (AFB). Replacement of the primary decontamination agent with CB-18 caused changes in all diagnostic parameters. Aggregate culture sensitivity improved by approximately 43% (P < 0.01), and smear sensitivity improved by approximately 58% (P < 0.01). The sensitivity of smear relative to that of M. tuberculosis isolates exceeded 93% (P < 0.01) when specimens were processed with CB-18. The average times to a positive result were reduced by 7.3 days in liquid culture (P < 0.01) and 5.3 days on solid media (P < 0.05); however, the CB-18 method had a 20.8% contamination rate in liquid culture versus a rate of approximately 7.5% with NALC/NaOH processing. There were also unusual reductions in liquid culture sensitivity and smear specificity among CB-18-processed specimens. The characteristics of the latter parameters suggested that refinement of the CB-18 processing method should allow further improvements in culture sensitivity. This study showed that the CB-18 method has the potential to improve both smear and culture detection for these important human pathogens.  相似文献   
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AIMS--To detect enteric microsporidia in faecal specimens from patients with the acquired immunodeficiency syndrome (AIDS), and to identify the spores to species level without using invasive procedures. METHODS--Formalised faecal preparations were examined using a modification of the strong trichrome staining method to demonstrate microsporidian spores. Six positive specimens were prepared for electron microscopy by emulsification and separation using a 9% Ficoll gradient. RESULTS--The modified staining technique readily identified microsporidian spores. Spores of different species showed variation in size. Identification using electron microscopy was successful for five of the six positive specimens examined. It was unsuccessful for one specimen in which spores were less abundant on initial staining. CONCLUSIONS--The modified strong trichrome staining method is a useful way of detecting spores of intestinal microsporidia in faecal specimens. Variation in spore size may permit provisional identification by light microscopy. Electron microscopic examination of faecal preparations is useful for identifying spores to species level.  相似文献   
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