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排序方式: 共有589条查询结果,搜索用时 15 毫秒
1.
2.
Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
3.
Classical and anaplastic seminoma: difference in survival 总被引:1,自引:0,他引:1
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma. 相似文献
4.
A J Stevenson M P Weber F Todi M Mendonca J D Fenwick L Young E Kwong F Chen P Beaumier S Timmings 《Journal of analytical toxicology》1992,16(2):93-96
The variability in plasma and urine equine procaine measurement between three independent laboratories using current methods led to the development of a sensitive, reliable, and reproducible high-performance liquid chromatographic method. Standardbred mares were administered either a penicillin G procaine preparation intramuscularly or procaine hydrochloride subcutaneously, and blood and urine were collected at defined time intervals. By HPLC the detection limits for procaine in plasma and urine were 1 and 10 ng/mL, respectively. In contrast procaine in plasma could not be detected by GC-NPD, while the urinary detection limit was 50 ng/mL. The concentration of fluoride in the collection tubes and repetitive freeze-thawing modified plasma procaine measurement. Urinary pH was a factor in estimation of urine procaine levels with greater recovery and reproducibility of results at pH 5 as compared to pH 7. This HPLC method provides a simple, sensitive, and reliable quantitation of procaine in equine plasma and urine. 相似文献
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7.
Seropositivity for and Intestinal Colonization with Entamoeba histolytica and Entamoeba dispar in Individuals in Northeastern Brazil
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Lucia L. Braga Yacy Mendonca Clece A. Paiva Andrea Sales Andre L. M. Cavalcante Barbara J. Mann 《Journal of clinical microbiology》1998,36(10):3044-3045
In a slum community in northeastern Brazil 20% of a sample population was colonized with Entamoeba histolytica or Entamoeba dispar and 10.6% was colonized with E. histolytica alone. No correlation between seropositivity for anti-GalNAc lectin antibody and colonization was found. These results suggest that colonization does not necessarily produce immunity to reinfection. 相似文献
8.
Longui CA Lemos-Marini SH Figueiredo B Mendonca BB Castro M Liberatore R Watanabe C Lancellotti CL Rocha MN Melo MB Monte O Calliari LE Guerra-Junior G Baptista MT Sbragia-Neto L Latronico AC Moreira A Tardelli AM Nigri A Taymans SE Stratakis CA 《Journal of medical genetics》2004,41(5):354-359
The R337H TP53 mutation is a low-penetrance molecular defect that predisposes to adrenocortical tumour (ACT) formation in Brazilian and possibly other populations. Additional genetic defects may be responsible for the variable expression of ACTs in these cases. The inhibin α-subunit gene (INHA) on 2q33-qter has been implicated in mouse adrenocortical tumourigenesis. We studied 46 pediatric patients with ACTs from Brazil for INHA genetic alterations; 39 of these patients were heterozygous carriers of the R337H TP53 mutation. We first mapped the INHA gene by radiation hybrid analysis and determined 10 linked microsatellite markers in an area flanked by D2S1371 and D2S206 on 2q33-qter. These markers were then used for loss of heterozygozity (LOH) studies in nine paired germline and tumour DNA samples. Mapping placed the INHA gene in close proximity to D2S2848 (SHGC11864) with a log of odds (LOD) score of 5.84. LOH for at least one marker in the region was identified in 8/9 tumours (89%). Six patients were heterozygous for three INHA mutations: one in exon 1, 127C>G, and two in exon 2, 3998G>A and 4088G>A, all leading to amino acid substitutions (P43A, G227R, and A257T, respectively). A257T is located in a conserved INHA region, highly homologous to transforming growth factor-ß; both G227R and A257T change polarity, and, in addition, G227R changes the pH. We conclude that these sequence alterations and the detected 2q allelic changes suggest that INHA may be one of the contributing factors needed for ACT formation in pediatric patient carriers of the R337H TP53 mutation. 相似文献
9.
Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis 总被引:7,自引:2,他引:7
Li DY; Toland AE; Boak BB; Atkinson DL; Ensing GJ; Morris CA; Keating MT 《Human molecular genetics》1997,6(7):1021-1028
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular
disease that affects the aorta, carotid, coronary and pulmonary arteries.
Previous molecular genetic data have led to the hypothesis that SVAS
results from mutations in the elastin gene, ELN. In these studies, the
disease phenotype was linked to gross DNA rearrangements (35 and 85 kb
deletions and a translocation) in three SVAS families. However, gross
rearrangements of ELN have not been identified in most cases of autosomal
dominant SVAS. To define the spectrum of ELN mutations responsible for this
disorder, we refined the genomic structure of human ELN and used this
information in mutational analyses. ELN point mutations co-segregate with
the disease in four familial cases and are associated with SVAS in three
sporadic cases. Two of the mutations are nonsense, one is a single base
pair deletion and four are splice site mutations. In one sporadic case, the
mutation arose de novo. These data demonstrate that point mutations of ELN
cause autosomal dominant SVAS.
相似文献
10.
Roberto Iglesias Lopes Caio Vinicius Suartz Rubens Pedrenho Neto Ricardo Haidar Berjeaut Berenice Mendonca Madson Q. Almeida Maria Cândida Villares Fragoso Francisco Tibor Dénes 《Journal of pediatric surgery》2021,56(4):768-771
AimThe aim of this study is to present our experience in the management of hormonally active adrenal tumors in children.Material and methodsWe did a retrospective chart review of all children with hormonally active adrenal tumors evaluated at the endocrinology clinic and operated at our institution between 1983 and 2019.ResultsThere were 75 patients included in the study, 58 with adrenocortical tumors (ACTs) and 17 with pheochromocytomas (PCCs). Within the group of patients with ACTs, there were 41 females and 17 males. The mean age was 58.3 (SD: 87.9; range: 9–211) months. The clinical manifestation of the tumor's hormonal activity was virilization in 37 cases, Cushing syndrome in 5, and mixed in 16. A positive family history was present in 11 patients (18.9%). The mean tumor size was 48.2 (SD: 22.4; range: 7–120) mm. The pathological diagnosis was adenoma in 42 cases, carcinoma in 15 cases, and macronodular hyperplasia in 1. Median follow-up was 192 (range: 50–290) months. Tumor recurrence occurred in 6 patients (10.3%), and there were three disease-related deaths (5%). Within the group of patients with PCCs, there were 11 males and 6 females. The mean age was 146.7 (SD: 71.2; range: 60–216) months. A positive family history was present in 7 patients (41.2%). The mean tumor size was 36.6 (SD: 16.7; range: 7–120) mm. The pheochromocytoma was classified as benign in 15 cases and as malignant in 2. During a median follow-up of 180 (range: 127–300) months, recurrence was observed in 6 cases (35.3%) and disease-related death in 1 case (5.9%).ConclusionsProper diagnosis and management at our referral center were associated with a high cure rate, even in cases of malignant tumors. Familial surveillance is highly recommended.Level of evidenceLevel IV. 相似文献