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31.
Summary Sulphasalazine in a dose of 50 mg/kg/day was administered to ten patients with pauciarticular-onset juvenile chronic arthritis (JCA), with active disease not adequately controlled by nonsteroidal anti-inflammatory drugs (NSAID). The treatment was initiated with 1/4 of this dose and increased by weekly increments of 250–500 mg until the total dose was reached. In all patients sulphasalazine was the first disease-modifying agent tried. Among nine of the ten patients there was significant improvement in all clinical scores, including the number of active joints and the severity grading (tenderness and limitation of motion). Within 3 months of sulphasalazine therapy the laboratory measurements revealed marked improvement in the erythrocyte sedimentation rate (ESR) and haemoglobin values. One patient, in whom the ESR and haemoglobin were normal at onset, had no change in clinical scores. Transient skin rash and elevated liver enzyme levels developed in one patient. These preliminary data suggest that sulphasalazine is an effective and safe second-line agent in the management of pauciarticular-onset JCA. More trials with this drug are needed, including double blind, to study efficacy and safety of sulphasalazine in JCA.  相似文献   
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Monocytoid B-cell lymphoma (MBCL) is a newly recognized B-cell neoplasm of uncertain histogenesis. The cytologic features of the neoplastic monocytoid B lymphocytes are virtually identical to those of hairy cell leukemia (HCL). As with HCL, progression of MBCL to a higher histologic grade is very unusual. However, whereas circulating leukemic cells are a characteristic feature of HCL, peripheral blood involvement has not been reported in MBCL. We recently studied a patient with MBCL of the spleen and axillary lymph nodes who developed peripheral blood involvement by MBCL cells. Unlike the cells of HCL, the circulating MBCL cells exhibited strong acid phosphatase activity that was tartrate sensitive. The leukemic cells had the antigenic phenotype IgM lambda, CD20+, CD11c+, CD5-, CD25(TAC)-, and PCA-1-. Immunogenetic studies of both lymph node and peripheral blood cells revealed identical immunoglobulin heavy-chain gene rearrangements. When compared with a series of HCL, the immunophenotype was similar except for the absence of PCA-1 and TAC. Progression of the MBCL to a large cell lymphoma, also expressing IgM lambda, was documented in an abdominal lymph node of this patient. Therefore, although rare, peripheral blood involvement by lymphoma cells may occur during the course of MBCL and should be distinguished from HCL with cytochemical and immunophenotypic studies. In addition, comparison of the clinical, pathologic, and immunologic features of MBCL with those of other low-grade B-cell neoplasms suggests that a close lineage relationship exists between MBCL and HCL.  相似文献   
34.
Objective: The objective of this study was to analyze the incidence of immunohistochemically detectable p53 protein accumulation in epithelial ovarian carcinomas and to correlate these data with the clinical outcome so as to clarify further the role of p53 mutations in prognosis with these patients.Methods: Tumor tissues from 179 patients with epithelial ovarian carcinoma were used for immuno-histochemical analysis with monoclonal antibody DO1 and BP 53-12-1 on formalin-fixed, paraffin-embedded tissue.Results: A total of 78 cases (44%) showed positive nuclear p53 staining. The p53-positive cases were found in all histological types of epithelial ovarian tumors. p53 staining was found in tumors of all stages with a higher percentage of positive cases in stage IV ovarian carcinomas (not significant). Poorly differentiated carcinomas showed a significantly higher percentage of p53 protein expression than did highly differentiated tumors (P=0.0002). Clinical follow-up of up to 14 years (median 25 months) showed a slightly but not significantly shortened disease-free and overall survival time for patients with p53-positive epithelial ovarian carcinomas.Conclusions: We conclude from our data that p53 expression in ovarian carcinoma is associated with poor differentiation but not with the disease being in an advanced stage. There was a tendency for shortened disease-free and overall survival for patients with p53-positive tumors.  相似文献   
35.
Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria.  相似文献   
36.
GH release in response to clonidine and human GH-releasing hormone-(1-44) (hGHRH-44) was assessed in 11 boys (aged 7-14 yr) with short stature, who had normal GH secretion. The response to these 2 provocative stimuli was repeated after, respectively, 2 and 3 days of treatment with human GH (0.1 U/kg, im). Exogenous GH significantly blunted the response to both clonidine [the mean 2-h integrated serum GH concentration falling from 1050 +/- 350 (+/- SEM) to 749 +/- 297 ng/ml X min; P = 0.03] and hGHRH-44, the 2-h integrated GH concentration falling from 1553 +/- 358 to 547 +/- 202 ng/ml X min; (P = 0.03). Plasma insulin-like growth factor (IGF-II) concentrations did not change after GH administration. In contrast, plasma IGF-I (somatomedin-C) concentrations increased from 97 +/- 16 ng/ml before administration of GH to 142 +/- 32 ng/ml (P = 0.05) after two days and 149 +/- 23 ng/ml (P less than 0.01) after the third treatment day. However, no correlation was found between the changes in response to clonidine or hGHRH-44 and changes in circulating levels of IGF-I. Our data confirm the existence of GH-dependent feedback inhibition of GH release during childhood and suggest that this inhibition operates, at least in part, at the level of the pituitary. While participation of the IGFs/somatomedins in this feedback loop cannot be excluded, the inhibitory effects of exogenous GH do not depend directly on circulating plasma IGF-I or IGF-II levels.  相似文献   
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Enteric-coated tablets leave the stomach mainly during the interdigestive phase. Composition as well as time of ingestion of meals may influence their gastric emptying considerably. In 12 normal volunteers gastric emptying of a plastic tablet with a metal core was followed by a metal detector in relation to different compositions and various times of ingestion of meals. With an empty stomach and after ingestion of 250 ml water, the mean time for gastric emptying of the tablet was 38 +/- 11 min (mean +/- SEM) and 38 +/- 8 min. Two hundred fifty milliliters of milk (652 kJ) and a formula diet (1000 kJ) delayed gastric emptying time to 128 +/- 14 and 152 +/- 6 min, respectively (P less than 0.05). Breakfast (2200 kJ) further retarded gastric emptying compared with both liquids to 249 +/- 24 min (P less than 0.05). There was a close correlation between nutritive density and gastric emptying of the tablet (r = 0.92; P less than 0.001). Main meals also delayed gastric emptying of tablets when compared to empty stomach (P less than 0.05). A snack after breakfast further delayed gastric emptying from 201 +/- 10 to 278 +/- 19 min (P less than 0.05). The largest delay was observed following ingestion of breakfast, lunch, dinner, and additional snacks (509 +/- 220 min). We conclude that the delay of gastric emptying of enteric-coated tablets by food is related to its nutritive density and eating habits. The gastric emptying of an enteric coated tablet that is ingested early in the morning may be delayed until late at night when several meals and snacks are ingested during the day, leading to unwanted alterations in bioavailability and to possible adverse effects.  相似文献   
39.
Mimuro  J; Schleef  RR; Loskutoff  DJ 《Blood》1987,70(3):721-728
The extracellular matrix (ECM) of cultured bovine aortic endothelial cells (BAEs) was analyzed by immunoblotting and reverse fibrin autography and shown to contain type 1 plasminogen activator inhibitor (PAI-1). Most PAI-1 in the ECM formed complexes with exogenously added tissue-type plasminogen activator (tPA), demonstrating that this PAI-1 was functionally active. The resulting tPA/PAI-1 complexes were recovered in the reaction solution, indicating that the PAI-1 in such complexes no longer bound to ECM. The PAI-1 could not be removed by incubating ECM in high salt (2 mol/L NaCl), sugars (1 mol/L galactose, 1 mol/L mannose), glycosaminoglycans (10 mmol/L heparin, 10 mmol/L dermatan sulfate), or epsilon-aminocaproic acid (0.1 mol/L). However, PAI-1 could be extracted from ECM by treatment with either arginine (0.5 mol/L) or potassium thiocyanate (2 mol/L), or by incubation under acidic conditions (pH 2.5). ECM depleted of PAI-1 by acid extraction was able to bind both the active and latent forms of PAI-1. In this instance, most of the bound PAI-1 did not form complexes with tPA, indicating that the latent form was not activated as a consequence of binding to ECM. Although the PAI-1 activity in conditioned medium decayed with a half-life (t 1/2) of less than 3 hours, the t 1/2 of ECM- associated PAI-1 was greater than 24 hours. These data suggest that PAI- 1 is produced by cultured BAEs in an active form and is then either released into the medium where it is rapidly inactivated or into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation.  相似文献   
40.
Precise FKS mutation rates among Candida species are undefined because studies have not systematically screened consecutive, disease-causing isolates. The Sensititre YeastOne (SYO) assay measures echinocandin MICs against Candida with less variability than reference broth microdilution methods. However, clinical breakpoint MICs may overstate caspofungin nonsusceptibility compared to other agents. Our objectives were to determine Candida FKS mutation rates by studying consecutive bloodstream isolates and to determine if discrepant susceptibility results were associated with FKS mutations. FKS hot spots were sequenced in echinocandin-intermediate and -resistant isolates and those from patients with breakthrough candidemia or ≥3 days of prior echinocandin exposure. Overall, 453 isolates from 384 patients underwent susceptibility testing; 16% were echinocandin intermediate or resistant. Intermediate susceptibility rates were higher for Candida glabrata than for other species (P < 0.0001) and higher for caspofungin than for other agents (P < 0.0001). Resistance rates were similar between agents. FKS mutations were detected in 5% of sequenced isolates and 2% of isolates overall. Corresponding rates among C. glabrata isolates were 8% and 4%, respectively. Among Candida albicans isolates, rates were 5% and <1%, respectively. Mutations occurred exclusively with prior echinocandin exposure and were not detected in other species. Isolates with discrepant susceptibility results did not harbor FKS mutations. Mutation rates among isolates resistant to ≥2, 1, and 0 agents were 75%, 13%, and 0%, respectively. In conclusion, FKS mutations were uncommon among non-C. glabrata species, even with prior echinocandin exposure. Discrepancies in echinocandin susceptibility by SYO testing were not driven by mutations and likely reflect imprecise caspofungin clinical breakpoints.  相似文献   
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