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1.
2.
Primary pulmonary hypertension in HIV infection 总被引:6,自引:0,他引:6
A prospective evaluation of 74 human immunodeficiency virus (HIV)-infected patients with cardiopulmonary complaints revealed six patients (8.1 percent) with pulmonary hypertension with elevated right ventricular systolic over right atrial pressure of 58 +/- 8 mm Hg (range, 49 to 66 mm Hg), as documented by Doppler echocardiography. A thromboembolic cause was excluded by normal lung perfusion scans. Electrocardiographic and roentgenographic features of pulmonary hypertension were present in five patients. Two patients died three and nine months after diagnosis of pulmonary hypertension. Autopsy revealed plexogenic pulmonary arteriopathy in both. The observation of six patients with primary pulmonary hypertension (PPH) in a cohort of 1,200 HIV-infected subjects corresponding to an incidence of 0.5 percent is striking and suggests a possible association of PPH with HIV infection. 相似文献
3.
P-fimbriae vaccines 总被引:3,自引:0,他引:3
M. Bernice Kaack Auli Pere Timo K. Korhonen Stefan B. Svenson James A. Roberts 《Pediatric nephrology (Berlin, Germany)》1989,3(4):386-390
To test for cross-protective capacity of two different P-fimbriae vaccines we vaccinated baboons with fimbriae purified from either Escherichia coli strain ER2 or strain JR1. The vaccinated animals showed elevated antibody titers to P-fimbriae from each of the E. coli strains used, suggesting cross-reactivity as was expected from the results of immunoprecipitation of the fimbriae. Enzyme-linked immunosorbent assay inhibition by heterologous P-fimbriae proved this to be true immunologic cross-reactivity. 相似文献
4.
M L Latvala T T Korhonen M Penttinen P Laippala 《The British journal of ophthalmology》1994,78(5):339-343
The ophthalmic findings of 55 dyslexic 12 to 13-year-old Finnish schoolchildren and 50 age, sex, and social class-matched control children were evaluated. On a neuropsychological basis the children could be divided into six subgroups: general deficiency, general language, visuomotor, naming, mixed, and normal. The two groups did not differ significantly from each other in visual acuity, cycloplegic refraction, the amount of phorias and tropias, stereo acuity, fusion, or accommodation. Convergence near point > or = 8 cm was, however, statistically more frequent in the dyslexic group. This finding was also significant in the general deficiency subgroup compared with the other subgroups. The most conspicuous common denominator in those with dyslexia was revealed to be the convergence insufficiency type of exodeviation, occurring in 38% of the general deficiency dyslexic subgroup and in 36% of the visuomotor dyslexic subgroup. This finding suggests a low accommodative convergence/accommodation ratio in these children. 相似文献
5.
The local mean and the average difference of four pairs of test locations within the 26° visual field, situated above and below the horizontal nasal meridian, were used to predict the global field indices MD and CLV of the Gl glaucoma program. Out of 539 examinations (194 eyes suspected of having glaucoma), the local indices NDIFF (describing asymmetrical behavior around the nasal horizontal meridian), ND0 (the mean defect in the nasal region), and the global indices MD and CLV were calculated. Seven hundred fifty-five examinations (446 normal eyes) served as a control group. First and second examinations of 146 glaucoma suspect eyes were used to calculate the retest reliability scores for the indices in question. When analyzing the glaucoma suspects, the local index NDIFF, together with the local mean defect, ND0, yielded highly reliable estimates of the global indices MD and CLV, with a retest correlation r = 0.86 for NDIFF, and r = 0.96 for ND0. The covariance of NDIFF with CLV was r = 0.67, while the co-variance of MD with ND0 was r = 0.95.The ranges of the local indices ND0 and NDIFF were each classified into normal range and range of suspected pathology, in analogy to the normal and pathological ranges of the global field indices. Equivalence of the local indices with the corresponding ranges of MD and CLV was investigated and the results are shown. The establishment of local indices may prove to be a powerful tool in early detection of glaucomatous damage. 相似文献
6.
Korhonen RK Wong M Arokoski J Lindgren R Helminen HJ Hunziker EB Jurvelin JS 《Medical engineering & physics》2002,24(2):99-108
Indentation testing is a widely used technique for nondestructive mechanical analysis of articular cartilage. Although cartilage shows an inhomogeneous, layered structure with anisotropic mechanical properties, most theoretical indentation models assume material homogeneity and isotropy. In the present study, quantitative polarized light microscopy (PLM) measurements from canine cartilage were utilized to characterize thickness and structure of the superficial, collageneous tissue layer as well as to reveal its relation to experimental indentation measurements. In addition to experimental analyses, a layered, transversely isotropic finite element (FE) model was developed and the effect of superficial (tangential) tissue layer with high elastic modulus in the direction parallel to articular surface on the indentation response was studied. The experimental indentation stiffness was positively correlated with the relative thickness of the superficial cartilage layer. Also the optical retardation, which reflects the degree of parallel organization of collagen fibrils as well as collagen content, was related to indentation stiffness. FE results indicated effective stiffening of articular cartilage under indentation due to high transverse modulus of the superficial layer. The present results suggest that indentation testing is an efficient technique for the characterization of the superficial degeneration of articular cartilage. 相似文献
7.
The omptins are a family of enterobacterial surface proteases/adhesins that share high sequence identity and a conserved beta-barrel fold in the outer membrane. The omptins are multifunctional, and the individual omptins exhibit differing virulence-associated functions. The Pla plasminogen activator of Yersinia pestis contributes by several mechanisms to bacterial invasiveness and the systemic, uncontrolled proteolysis in plague. Pla proteolytically activates the human proenzyme plasminogen and inactivates the antiprotease alpha2-antiplasmin, and its binding to laminin localizes the uncontrolled plasmin activity onto basement membranes. These properties enhance bacterial migration through tissue barriers. Pla also degrades circulating complement proteins and functions in bacterial invasion into human epithelial cells. PgtE of Salmonella enterica and OmpT of Escherichia coli have been shown to degrade cationic antimicrobial peptides from epithelial cells or macrophages. PgtE and SopA of Shigella flexneri appear important in the intracellular phases of salmonellosis and shigellosis, whereas functions of OmpT have mainly been associated with protein degradation in E. coli cells. The differing virulence roles and functions have been attributed to minor sequence variations at the surface-exposed regions important for substrate recognition, to the dependence of omptin functions on lipopolysaccharide, and to the different regulation of omptin expression. 相似文献
8.
Event-related potentials (ERPs) to visual stimuli were recorded from the scalp of eight adult humans performing a task in which they counted vowels from a heard story. In the oddball condition, a repeated (standard) light bar of 50 ms in duration was rarely (P = 0.1) replaced by a (deviant) one differing in orientation from the standard. In the control condition, standards were simply omitted from the series and only (alone-) deviants retained. In both conditions, visual stimuli were asynchronous with auditory-task-relevant stimuli. ERPs to deviants significantly differed in amplitude from those to standards in the midline electrodes centrally, parietally and occipitally at 160-200 ms from stimulus onset. Occipitally, such a difference was absent between ERPs to alone-deviants and those to standards. The occipital differential ERPs to deviants, which thus could be found only when standards were present in the series, are discussed in the context of the mismatch negativity (MMN). 相似文献
9.
J. Wahlfors J. H. Meurman J. Toskala A. Korhonen P. Alakuijala E. Janatuinen U. M. Kärkkkäinen P. Nuutinen J. Jänne 《European journal of clinical microbiology & infectious diseases》1995,14(9):780-786
A rapid and simple polymerase chain reaction (PCR) method was developed to detectHelicobacter pylori in gastric biopsy specimens and dental plaque samples. The primers were targeted to the 16S rRNA sequence ofHelicobacter pylori strain ATCC 43504. The system was found to have a theoretical detection level of 0.5 to 5Helicobacter pylori cells in a 5 l sample of dental plaque. In the absence of plaque, the detection level was even better: theoretically, 0.05 to 0.5Helicobacter pylori cells were detected in water suspension. However, this appeared to be due to the presence of free bacterial DNA in the culture used for the sensitivity determination. Thus, the actual sensitivity of the system was found to be fewer than fiveHelicobacter pylori cells, irrespective of the type of sample used. The method was then used to analyse 29 dental plaque and gastric biopsy specimens collected from patients with a history of recurrent peptic ulcer disease. Fourteen stomach specimens were positive forHelicobacter pylori when tested with the PCR method, while the respective figures with culture, histological examination and the urease test were 11, 12 and 9. No positive dental plaque samples were observed. 相似文献
10.
R. Christen R. Morant J. Schneider R. Jenni J. Fehr 《Journal of molecular medicine (Berlin, Germany)》1989,67(6):358-365
Summary A female patient is described in whom the diagnosis of idiopathic hypereosinophilic syndrome (HES) with heart disease and peripheral neuropathy was made at the age of 32 years. Although prednisone induced a prompt and longstanding complete hematological remission, progressive and eventually intractable heart failure developed, and the patient died 6 years later. Endomyocardial biopsy at diagnosis showed infiltration with intact and disintegrated eosinophils and Charcot-Leyden crystals. Echocardiographic follow-up (including Doppler-Echocardiography) revealed mitral regurgitation with thickening and impaired motility of the posterior mitral leaflet, as well as progressive dilated cardiomyopathy. At autopsy, a diffuse interstitial fibrosis with patchy prominence in an eccentric hypertrophic and highly dilated heart was found. There were no significant endocardial thickening and no mural thrombi. In contrast to the findings of the initial endomyocardial biopsy, autopsy revealed no eosinophilic infiltrate.In this case, eosinophil-induced heart disease manifested as dilated cardiomyopathy, without endocardial fibrosis as originally described by Löffler. We speculate, that eosinophils have been deposited predominantly in the myocard at an early stage of disease, and — activated locally — secreted their granule proteins producing an initial damage to capillary endothelial cells and myocytes. After prednisone-induced clearance of eosinophils from blood and tissues, progressive, self-perpetuating interstitial fibrosis of the myocard and loss of myocytes eventually resulted in end-stage dilated cardiomyopathy.Abkürzungsverzeichnis HES
idiopathic hypereosinophilic syndrome
- UBBC
unsaturated vitamin B12 binding capacity
- ECP
eosinophil cationic protein
- MBC
major basic protein
- EDD
end-diastolic diameter of the left ventricle
- LA
left atrium diameter
- LVEDP
left ventricular end-diastolic pressure
- NIH
National Institutes of Health 相似文献