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951.
We report here on five new cases of solid and cystic papillary neoplasm (SCPN) of the pancreas diagnosed by fine-needle aspiration cytology (FNAC). All cytologic samples were obtained by ultrasonography, and the smears were conventionally fixed and stained. Special histochemical and immunocytochemical stains were also performed in some samples. Cytology revealed in all but one case numerous pseudopapillary structures composed of fibrovascular stalks lined with one or more layers of bland-appearing, uniform tumor cells. The tumor cells had round-to-oval euchromatic nuclei with frequently folded smooth contours and one or two small nucleoli. Their cytoplasm often contained eosinophilic, PAS-positive, and diastase-resistant inclusions. Foamy cells, psammoma bodies, blood, and cellular debris were found in the background. The criteria for the differential diagnosis versus other pancreatic lesions are discussed in some detail, as is the role of immunocytochemistry (ICC). In the literature, only 28 cases of cytologically investigated SCPN have been reported to the best of our knowledge. The most helpful criteria for the conclusive identification of SCPN by FNAC include the pseudopapillary arrangement with bland-appearing tumor cells, and, especially, the finding of acidophilic, PAS-positive, and diastase-resistant cytoplasmic granules. 相似文献
952.
953.
PURPOSE: We report the case of a renal transplant recipient with rectal lymphoma manifested by sudden onset of abdominal pain from a perforated rectum who was treated successfully with prompt surgical resection and reduction of immunosuppressants. METHODS: An emergent anterior resection with Hartmann's procedure was done. Immunosuppressants were drastically reduced by discontinuation of cyclosporine. RESULTS: Pathologic examination showed diffusely infiltrated large-cell malignant lymphoma with an immunoblastic feature. The patient has been followed-up for four years, with no tumor recurrence or graft rejection. CONCLUSION: Rectal lymphoma, although rare, should be kept in the list of differential diagnoses for transplant recipients who exhibit lower gastrointestinal bleeding, intestinal obstruction, or abdominal pain. 相似文献
954.
A McEntegart E Morrison HA Capell MR Duncan D Porter R Madhok EA Thomson 《Canadian Metallurgical Quarterly》1997,56(7):410-413
OBJECTIVE: Social deprivation is now recognised to have an important impact on morbidity and mortality. This study sought to ascertain the effect of deprivation, if any, on disease severity, functional disability, and outcome in rheumatoid patients in Glasgow. METHODS: 814 patients with rheumatoid arthritis (RA) were assessed for clinical, functional, and laboratory indices of disease activity. Deprivation categories for individual patients were determined using the Carstairs index. Five year follow up is available for 440 patients. RESULTS: The study population of RA patients live largely in the most deprived areas. Patients from deprived areas have significantly poorer function at outset and at five years as defined by the Health Assessment Questionnaire (HAQ) score. This is not attributable to differences in disease duration in patients from the most deprived regions or compliance with treatment. Furthermore, these patients do not achieve over five years the initial functional level of those living in the most advantaged localities. CONCLUSION: RA patients from deprived areas have poorer function, which is associated with greater need--medical, social, and paramedical. Strategies and resources for healthcare need to be adjusted according to this variation. 相似文献
955.
Microsatellite polymorphisms are invaluable for mapping vertebrate genomes. In order to estimate the occurrence of microsatellites in the rabbit genome and to assess their feasibility as markers in rabbit genetics, a survey on the presence of all types of mononucleotide, dinucleotide, trinucleotide and tetranucleotide repeats, with a length of about 20 bp or more, was conducted by searching the published rabbit DNA sequences in the EMBL nucleotide database (version 323). A total of 181 rabbit microsatellites could be extracted from the present database. The estimated frequency of microsatellites in the rabbit genome was one microsatellite for every 2-3 kb of DNA. Dinucleotide repeats constituted the prevailing class of microsatellites, followed by trinucleotide, mononucleotide and tetranucleotide repeats, respectively. The average length of the microsatellites, as found in the database, was 26, 23, 23 and 22 bp for mono-, di-, tri- and tetranucleotide repeats, respectively. The most common repeat motif was AG, followed by A, AC, AGG and CCG. This group comprised about 70% of all extracted rabbit microsatellites. About 61% of the microsatellites were found in non-coding regions of genes, whereas 15% resided in (protein) coding regions. A significant fraction of rabbit microsatellites (about 22%) was found within interspersed repetitive DNA sequences. 相似文献
956.
957.
BACKGROUND: Cow's milk is one of the most common food allergens in children. Limited information is available on the prevalence of reactivity to a related food source, beef. The purposes of this study were to examine the prevalence of symptomatic sensitivity to beef in a selected pediatric population and to determine the frequency of concomitant reactivity to cow's milk and beef. METHODS: Children referred for assessment of atopic dermatitis and possible food hypersensitivity were evaluated for symptomatic reactivity to beef by double-blind placebo-controlled food challenges (DBPCFCs) and subsequent open feedings of beef. Sodium dodecyl-sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblot, and immunodot blot analyses were performed with patients' sera on preparations of beef extracts subjected to different cooking conditions: raw (no heating), medium, and well-cooked. RESULTS: Eleven of 335 children referred for evaluation of atopic dermatitis and possible food hypersensitivity were found to have symptomatic sensitivity to beef; eight were also sensitive to milk, as demonstrated in previous DBPCFCs. Eight patients reacted to beef during DBPCFC, and three tolerated beef in a DBPCFC and well-cooked beef in an open challenge but reacted to ingestion of less well-cooked beef. SDS-PAGE of raw beef revealed at least 24 protein fractions. Several protein bands in raw beef appeared to denature with heating. Bovine serum albumin and bovine gamma globulin were heat-labile in the beef extract, but six protein fractions persisted even after heating the beef extract for 2 hours at 85 degrees C. IgE from patients reacting to rare and well-cooked beef bound up to six of these heat-resistant fractions, but IgE from patients reacting only to rare beef failed to bind any of these fractions with one exception. In addition, patients reacting to rare and well-cooked beef had specific IgE to a 17.8 kd fraction, which was only weakly recognized by one patient reacting only to rare beef. CONCLUSIONS: Specific IgE antibodies to heat-labile beef proteins might explain why some patients can tolerate well-cooked beef but not medium-rare and rare beef. Patients reacting only to rare beef may not need to maintain a complete beef elimination diet. 相似文献
958.
Comparison of regularly scheduled with as-needed use of albuterol in mild asthma. Asthma Clinical Research Network 总被引:1,自引:0,他引:1
JM Drazen E Israel HA Boushey VM Chinchilli JV Fahy JE Fish SC Lazarus RF Lemanske RJ Martin SP Peters C Sorkness SJ Szefler 《Canadian Metallurgical Quarterly》1996,335(12):841-847
This in vitro study investigated the temperature changes experienced during electric welding of titanium to determine if the welding heat presented a potential danger to pulpal vitality. Welds were applied to cast titanium simulations of a three-unit fixed partial denture containing two thermocouples measuring temperature changes. Mean maximal temperature changes were 127.4 degrees F near the weld and 68.6 F degrees at the axial wall. The mean times for the temperature to drop to within 10.0 degrees F of the starting temperature ranged from 84.1 to 133.7 seconds. The relatively low temperatures recorded in this study suggest that further investigation is warranted into the use of the welder intraorally. 相似文献
959.
A cross-sectional study was done, focusing on the prevalence of exercise-induced asthma in Jamaica and variables that may account for this rate. No previous study of this nature had been undertaken, and the investigators contend that there is a need to identify children who suffer from this condition but are unaware of it. A sample of 214 students from primary and secondary schools in the Corporate Area were chosen and given questionnaires to complete. Eighty-four of the children reported a history consistent with that of exercise-induced asthma and were further subjected to stress testing for a definitive diagnosis of this condition. A prevalence of 20.8% [C.I. +/- 5.35] was identified which reflected a rate comparable to that recorded in North America. There was a significantly higher prevalence in children of primary school ages, but all other variables considered for significance testing to determine associations between these and the prevalence of EIA proved not significant. A recommendation has been made for opportunity screening by medical practitioners. 相似文献
960.
HA Martin 《Canadian Metallurgical Quarterly》1996,104(2):229-238
Endothelin-1 (Et-1) is a 21-amino acid peptide primarily synthesized by endothelial cells. It was originally classified as a potent vasoconstrictor but recent evidence suggests that it also possesses a wide variety of non-vascular actions. It stimulates fibroblast and smooth muscle cell proliferation and it has been shown to stimulate fibroblast collagen metabolism. However, studies on its ability to regulate collagen production remain incomplete, and its effect on post-translational processing of procollagen has not been studied. This report details the effect of Et-1 on the rates of procollagen synthesis and degradation in two fibroblast cell lines; human foetal lung (HFL-1) and whole foetal rat fibroblasts (Rat 2). Fibroblast cultures were incubated for 24 hr in the presence or absence of Et-1 before procollagen metabolism was determined by measuring hydroxyproline. Non-collagen metabolism was also determined in these cultures from the uptake of tritiated phenylalanine. Et-1 stimulated procollagen synthesis in HFL-1 fibroblasts and reduced synthesis in Rat 2 cells. The response was dose dependent with the greatest effect at 1.10(-6) M Et-1 for both cell types (155 +/- 6% of control (mean +/- SD, n = 6, P < 0.01) and 61 +/- 4% of control (n = 4, P < 0.01) for HFL-1 and Rat 2 fibroblasts, respectively). Non-collagen protein synthesis was increased to 148 +/- 5% of control (P < 0.05) at 1.10(-6) M Et-1. Non-collagen protein synthesis remained unaffected in the HFL-1 fibroblast cultures. Procollagen degradation, expressed as a proportion of total procollagen synthesis, was decreased in HFL-1 fibroblasts (control, 29 +/- 2%; Et-1, 1.10(-6) M; 21 +/- 2%; P < 0.01), and increased in Rat 2 fibroblasts (control 42 +/- 1%; Et-1, 1.10(-6) M; 49 +/- 1%; P < 0.01). Blocking of the EtA receptor for Et-1, using the receptor antagonist-BQ123, abolished the effect of Et-1 on procollagen metabolism in both cell types. These results suggest that different populations of fibroblasts exhibit heterogeneous responses to Et-1. It is concluded that Et-1 may play an important role in the extent and distribution of fibrosis seen in diseases associated with the overproduction of Et-1. 相似文献