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101.
Criteria for the classification of juvenile rheumatoid arthritis were analyzed in a detailed database of 250 children in order to assess the accuracy of diagnosis and validity of onset types and course subtypes. A number of conclusions have been derived from this study: All definitions of the 1973 criteria for classification of juvenile rheumatoid arthritis should be retained. The addition of onset types to the 1976 revision of the criteria has been validated. The course of the disease after the onset period of 6 months is as important to the outcome of a group of children as is the onset type. The current classification should be broadened to include the course subtypes.  相似文献   
102.
The properties of 709 strains of Escherichia coli isolated from feces of healthy schoolchildren were compared with those of 115 strains from the urine of girls with asymptomatic bacteriuria (ABU) detected in a screening program. These fecal strains were also compared with 45 strains that caused asymptomatic reinfections and 10 that caused symptomatic reinfections in the same group of girls. Typing of O antigen was done by direct bacterial agglutination, and K typing was done with a serum agar technique. Hemolytic capacity was assessed in solid medium. Sensitivity to the bactericidal effect of normal serum and minimal inhibitory concentrations of ampicillin were also determined. The strains isolated from girls who had reinfections of ABU were found to be a random sample of the fecal flora, but the strains from children with symptomatic reinfection were not. Strains from index patients with ABU differed from the other groups in a way that was indicative of adaptive changes in the structure of cell envelopes.  相似文献   
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The relationship of the numbers of amastigotes in the liver to the duration of infection with two lines of a Khartoum strain of Leishmania donovani [designated the parent (P) line and the meglumine antimoniate (Glucantime) resistant (MAR) line] and the effect of meglumine antimoniate on these two lines of Leishmania were studied in the squirrel monkey. All experimental monkeys were inoculated via the saphenous vein with 32.5 X 10(6) amastigotes (per kg body weight), obtained from heavily-infected hamster spleens. Subsequently in Experiment I, liver biopsy samples were taken chronologically from all monkeys. Imprints of liver were made on glass slides and stained with Giemsa's staining solution, and parasite density per gram of liver tissue was determined. The parasites reached a maximum density of 6.2 X 10(6) amastigotes per gram between two to four weeks and 9.4 X 10(7) amastigotes per gram between four to six weeks in the monkeys receiving the P line and the MAR line, respectively. Parasite numbers then decreased, and all the livers and spleens of all monkeys became microscopically negative for Leishmania eight to 13 weeks post-infection. Comparison of the multiplication of the two lines of Leishmania indicated that the MAR line persisted longer in the livers than did the P line. A slight decrease in body weight was observed at eight weeks post-infection. Packed cell volume and haemoglobin were low at four to eight weeks post-infection, but were within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
108.
Objectives: The purpose of this study was to establish that the prostacyclin (PGI2) receptor (IP receptor) is present on rabbit and human erythrocytes and that its activation stimulates cyclic adenosine monophosphate (cAMP) synthesis and adenosine triphosphate (ATP) release. Methods: The effect of incubation of erythrocytes with the active PGI2 analogs, iloprost or UT‐15C, on cAMP levels and ATP release was determined in the absence and presence of the IP receptor antagonist, CAY10441. Western analysis was used to determine the presence of the IP receptor on isolated membranes. To establish that effects of PGI2 analogs were not due to prostaglandin E2(PGE2) receptor activation, the effect of PGE2 on cAMP levels and ATP release was determined. Results: Rabbit and human erythrocytes possess IP receptors. Iloprost and UT‐15C stimulated increases in cAMP and ATP release that were prevented by the IP receptor antagonist, CAY10441. PGE2 did not stimulate cAMP accumulation or ATP release and did not inhibit iloprost‐induced increases in cAMP. Conclusions: This study establishes that the IP receptor is present on rabbit and human erythrocytes and that its activation results in increases in cAMP and ATP release. These results suggest a novel mechanism by which PGI2 and its active analogs, when administered pharmacologically, could produce vasodilation.  相似文献   
109.
The hemodynamic and angiographic data of 147 individuals were analyzed in an attempt to assess the value of three techniques used in the diagnosis of mitral incompetence. One hundred patients had clinical evidence of mitral incompetence (group A) and 47 had normal hemodynamics (group B). The degree of mitral incompetence was assessed in all 147 individuals by two methods: determination of a regurgitant index (RI) using indicator dilution curves and determination of a regurgitant fraction (RF) using left ventricular volumes. In 26 patients of group A and 26 individuals in group B mitral incompetence was also assessed by cineangiocardiography. Each of these methods was compared with the clinical and hemodynamic evidence of mitral valvular incompetence. Both the determination of RI by dye dilution curves and RF by angiocardiography were found to be useful in separating normal individuals from patients with mitral valvular incompetence. Severe mitral incompetence is associated with an RI greater than 35% and with an RF greater than 55%. The degree of incompetence by either method was not well correlated with any independent hemodynamic variable. The use of cine angiocardiography to quantify the degree of mitral incompetence was found to be too subjective, depending on the observer, and thus less useful.  相似文献   
110.
Several single nucleotide polymorphisms (SNPs) associated with type 2 diabetes mellitus (T2DM) have been identified, but there is little information on their role in populations at high risk for T2DM. We genotyped SNPs at 63 T2DM loci in 3,421 individuals from a high-risk American Indian population. Nominally significant (P < 0.05) associations were observed at nine SNPs in a direction consistent with the established association. A genetic risk score derived from all loci was strongly associated with T2DM (odds ratio 1.05 per risk allele, P = 6.2 × 10−6) and, in 292 nondiabetic individuals, with lower insulin secretion (by 4% per copy, P = 4.1 × 10−6). Genetic distances between American Indians and HapMap populations at T2DM markers did not differ significantly from genomic expectations. Analysis of U.S. national survey data suggested that 66% of the difference in T2DM prevalence between African Americans and European Americans, but none of the difference between American Indians and European Americans, was attributable to allele frequency differences at these loci. These analyses suggest that, in general, established T2DM loci influence T2DM in American Indians and that risk is mediated in part through an effect on insulin secretion. However, differences in allele frequencies do not account for the high population prevalence of T2DM.  相似文献   
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