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41.
Data are presented on the family distribution of nearsightedness, including the frequency of the disorder in the children of two myopes. The previous literature is reviewed, embracing several quantitative family or population studies in addition to extensive pedigree material. It is concluded that there is substantial evidence that recessive inheritance is the principal mechanism of transmission, and that most instances of myopia probably fall into that category. 相似文献
42.
Evaluation of the E test for susceptibility testing of anaerobic bacteria. 总被引:10,自引:11,他引:10 下载免费PDF全文
D M Citron M I Ostovari A Karlsson E J Goldstein 《Journal of clinical microbiology》1991,29(10):2197-2203
The susceptibilities of 105 clinical isolates of anaerobic bacteria were determined by a new method, the E test (AB Biodisk, Solna, Sweden), and were compared with the MICs for these organisms obtained by the reference agar dilution method by using supplemented brucella and Wilkins-Chalgren agars. The E test is a plastic strip with a predefined antibiotic gradient immobilized on one side and a MIC interpretive scale printed on the other side. Strips with cefoxitin, cefotaxime, imipenem, penicillin, metronidazole, and clindamycin were used in this study. A suspension of the test strain equal to the visual turbidity of a no. 0.5 McFarland standard was prepared and swabbed onto a 150-mm-diameter plate. The strips were applied in a radial fashion, and the plates were incubated under anaerobic conditions. After growth had occurred, an ellipse of inhibition was seen around each strip. At the point of intersection of the ellipse with the strip, the MIC was read from the interpretive scale. For most antibiotic-organism combinations, the ellipse was clear and the endpoint was sharp. The E-test MICs were interpreted after overnight and 48-h incubation for 58 of the strains. After overnight incubation, 87% of the E-test MICs were within 1 dilution of the agar dilution MICs, and 98% were within 2 dilutions. After 48 h of incubation, agreement was 86 and 97% respectively. E-test MICs obtained for the Bacteroides fragilis group after overnight incubation were more comparable than those obtained after 48 h of incubation to agar dilution MICs determined at 48 h for all drugs except clindamycin. On brucella agar, there was a 2% categorical discrepancy rate between the E-test MICs and agar dilution MICs, which occurred mostly with cefoxitin. The E test is easy to perform and read, is suitable for all anaerobes, can be used to test single patient isolates as needed, and offers the laboratory a reliable method for susceptibility testing of anaerobic bacteria. 相似文献
43.
R. Karlsson B. Agrell S. Dreborg T. Foucard N.-I. M. Kjellman A. Koivikko R. Einarsson 《Allergy》1986,41(2):141-150
This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarum allergen preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment. IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' active treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarum, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment. 相似文献
44.
H E Carlsson A A Lindberg G Lindberg B Hederstedt K A Karlsson B O Agell 《Journal of clinical microbiology》1979,10(5):615-621
The enzyme-linked immunosorbent assay (ELISA) was applied for immunological diagnosis of human tularemia, using lipopolysaccharide from Francisella tularensis as antigen. Sera collected from patients, healthy individuals, and vaccinated volunteers were investigated for antibodies against F. tularensis by ELISA and tube agglutination. In ELISA all sera were titrated with a polyspecific anti-immunoglobulin enzyme conjugate. A limited number of consecutive sera from individual patients were also investigated for immunoglobulin G (IgG) and IgM antibodies by means of immunoglobulin class-specific conjugates. On an average ELISA was more than 10-fold as sensitive as tube agglutination. Two weeks after onset of disease, sera from patients had significantly higher titers in ELISA than sera from healthy controls. High titers persisted after more than 2 years. Significant amounts of both IgG and IgM antibodies were present within 1 to 2 weeks after infection. The antibody activity increased during the first month, without any significant change of the relation between IgG and IgM titers. After 2.5 years the IgG/IgM titer ratio of sera from patients was significantly increased. Within 6 weeks after vaccination sera from about half of the vaccinees had significantly elevated titers in ELISA. Titers observed after vaccination were generally lower than those found after infection. An elevated ELISA titer can be of diagnostic importance by the end of the first week of illness. A significant increase of titer in consecutive serum samples indicates a diagnosis of tularemia. Determination of IgG and IgM antibodies may be of value in determing whether a positive titer of a single serum sample is of longstanding or recent origin. 相似文献
45.
Development of porcine pancreatic hydrolases and their isoenzymes from the fetal period to adulthood
The appearance and activity of various porcine pancreatic hydrolases were studied during fetal and postnatal development. Quantitatively, the enzyme activities in activated pancreas homogenates were low but increased during the second half of the fetal period, using the substrates Bz-Arg-pNA for measuring anodal and cathodal trypsin, Suc-Phe-pNA (chymotrypsin A and C, and elastase II) and Suc-(Ala)3-pNA (elastase I and protease E). Postnatally, after an initial decrease during the first week, the enzyme activities increased markedly, especially from 10-14 weeks to 6 months. The individual hydrolases were identified after electrophoretic separation in agarose gel and staining with various substrates either directly in the gel or after transfer to nitrocellulose membranes (enzymoblotting). During the fetal period, chymotrypsin A and B, elastase II, carboxypeptidase A, and amylase appeared at approximately 65 days and anodal trypsin, at approximately 76 days. After birth, new proteinases appeared after the first week including chymotrypsin C, cathodal trypsin, and protease E, whereas elastase I was found from 5 weeks after birth. Concomitantly, unidentified "fetal proteinase(s)" with caseinolytic, Ac-Phe-beta NE and CBZ-Ala-beta NE activities began to diminish and disappeared 10-14 weeks after birth. This study showed a marked increase in the overall pancreatic enzyme activities, as well as an age-dependent expression of the variety of pancreatic hydrolases during porcine ontogeny. 相似文献
46.
Nicholas C Harvey Eric Orwoll Timothy Kwok Magnus K Karlsson Björn E Rosengren Eva Ribom Jane A Cauley Peggy M Cawthon Kristine Ensrud Enwu Liu Alfonso J Cruz-Jentoft Roger A Fielding Cyrus Cooper John A Kanis Mattias Lorentzon Claes Ohlsson Dan Mellström Helena Johansson Eugene McCloskey 《Journal of bone and mineral research》2021,36(7):1235-1244
Dual-energy X-ray absorptiometry (DXA)-derived appendicular lean mass/height2 (ALM/ht2) is the most commonly used estimate of muscle mass in the assessment of sarcopenia, but its predictive value for fracture is substantially attenuated by femoral neck (fn) bone mineral density (BMD). We investigated predictive value of 11 sarcopenia definitions for incident fracture, independent of fnBMD, fracture risk assessment tool (FRAX®) probability, and prior falls, using an extension of Poisson regression in US, Sweden, and Hong Kong Osteoporois Fractures in Men Study (MrOS) cohorts. Definitions tested were those of Baumgartner and Delmonico (ALM/ht2 only), Morley, the International Working Group on Sarcopenia, European Working Group on Sarcopenia in Older People (EWGSOP1 and 2), Asian Working Group on Sarcopenia, Foundation for the National Institutes of Health (FNIH) 1 and 2 (using ALM/body mass index [BMI], incorporating muscle strength and/or physical performance measures plus ALM/ht2), and Sarcopenia Definitions and Outcomes Consortium (gait speed and grip strength). Associations were adjusted for age and time since baseline and reported as hazard ratio (HR) for first incident fracture, here major osteoporotic fracture (MOF; clinical vertebral, hip, distal forearm, proximal humerus). Further analyses adjusted additionally for FRAX-MOF probability (n = 7531; calculated ± fnBMD), prior falls (y/n), or fnBMD T-score. Results were synthesized by meta-analysis. In 5660 men in USA, 2764 Sweden and 1987 Hong Kong (mean ages 73.5, 75.4, and 72.4 years, respectively), sarcopenia prevalence ranged from 0.5% to 35%. Sarcopenia status, by all definitions except those of FNIH, was associated with incident MOF (HR = 1.39 to 2.07). Associations were robust to adjustment for prior falls or FRAX probability (without fnBMD); adjustment for fnBMD T-score attenuated associations. EWGSOP2 severe sarcopenia (incorporating chair stand time, gait speed, and grip strength plus ALM) was most predictive, albeit at low prevalence, and appeared only modestly influenced by inclusion of fnBMD. In conclusion, the predictive value for fracture of sarcopenia definitions based on ALM is reduced by adjustment for fnBMD but strengthened by additional inclusion of physical performance measures. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献
47.
Induction of circulating activated suppressor-like T cells by methimazole therapy for Graves' disease 总被引:6,自引:0,他引:6
T H T?tterman F A Karlsson M Bengtsson I Mendel-Hartvig 《The New England journal of medicine》1987,316(1):15-22
Thyrostatic drug treatment of Graves' disease suppresses excessive thyroid hormone synthesis and causes a parallel decrease in serum thyroid autoantibody levels. The mechanism of this immunosuppression is unknown. We studied methimazole-induced immunoregulatory effects prospectively in 14 patients with Graves' disease treated for up to six months. The numbers of circulating activated, HLA-DR-positive T helper/inducer cells decreased gradually, from 8.3+1.7 percent (+SD) to 1.0+1.7 percent (P less than 0.001). HLA-DR-positive T suppressor/cytotoxic cells increased transiently at one month, from 2.0+1.9 percent to 12.6+6.4 percent (P less than 0.001), and returned to 2.9+3.7 percent at six months. Methimazole did not alter the HLA-DR expression of T cells in vitro. In two patients, the helper activity of T cells in inducing autoantibody secretion in vitro was substantially reduced after one month of methimazole treatment. Before treatment, large proportions of thyroid-infiltrating T-cell subsets expressed the activation markers HLA-DR, interferon-gamma, and interleukin-2 receptors, which were partially lost during therapy. Methimazole treatment was accompanied by a gradual reduction in circulating levels of thyrotropin-receptor, microsomal, and thyroglobulin autoantibodies. These results are compatible with the view that methimazole-induced immunoregulation in Graves' disease is mediated by a direct inhibitory effect on thyrocytes. This inhibition is in turn accompanied by marked changes in the proportions of activated T helper-like and T suppressor-like cells. This altered T-cell activation profile reflects, at least in part, the functional suppression of autoantibody production observed in methimazole-treated patients with Graves' disease. 相似文献
48.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
49.
Jan -Erik Karlsson Anders Björkholm Eva Nylander Jan Ohlsson Lars Wallentin 《The International Journal of Cardiac Imaging》1995,11(2):127-137
The additional value of thallium-201 SPECT to a conventional exercise test for the identification of patients with severe coronary lesions was evaluated in 170 men, one month after an episode of unstable coronary artery disease. Severe coronary lesions at coronary angiography — defined as three vessel disease, left main stenosis or proximal left anterior descending artery stenosis as part of two vessel disease — were observed in 45.9%. In the SPECT image, the left ventricular myocardium was divided into nine segments and each segment was classified as either normal (=0), reduced uptake (=1) or uptake defect (=2). The sum of gradings in all segments post-exercise was denoted SPECT score. The patients were divided into nine different groups regarding ST-depression during exercise (no ST-depression, ST-depression in 1–2 leads or 3 leads) and SPECT score (no SPECT score, 1–3 scores or 4 scores). Severe coronary lesions were, in 68% identified by SPECT score 4 and in 65% by ST-depression in 1 lead at exercise test. The specificity for identification of severe coronary lesions was, for both tests, 65%. SPECT score 4 and/or ST-depression in 3 leads identified 82% of the patients with severe coronary lesions with a specificity of 63%. Furthermore, SPECT score 3 identified more patients with isolated proximal left anterior descending artery stenosis than ST-depression alone at exercise test. 相似文献
50.
B Gulyás C Halldin P Karlsson Y H Chou C G Swahn P B?n?czk L Farde 《Orvosi hetilap》1999,140(30):1687-1691
Vinpocetine, a vinca alkaloid, is a therapeutic agent widely used in the treatment of acute and chronic stroke patients. To explore the uptake and distribution of vinpocetine in the primate brain, vinpocetine was labelled with 11C and positron emission tomography (PET) was used to measure the uptake and distribution of 11C-vinpocetine in the brain and the trunk of a cynomolgous monkey. HPLC was used to determine the concentration of vinpocetine and its labelled metabolites in blood and plasma. Following the radioligand's intravenous administration, after an initial peak, the total concentration of radioactivity in blood was relatively stable with time. The uptake of 11C-vinpocetine into the brain was rapid and about 5% of the total injected radioactivity was present in the brain two minutes after drug administration. These facts indicate that the compound passes the blood-brain barrier readily and enters the brain. The radioactivity uptake was heterogeneously distributed among brain regions. The highest concentrations were found in the thalamus, the basal ganglia and certain neocortical regions. In an earlier PET investigation on chronic stroke patients the highest increases in cerebral blood flow and glucose metabolism after intravenous vinpocetine treatment occurred in these anatomical structures. The heterogenous regional distribution of vinpocetine and the observation that the highest uptake values in brain structures go parallel with the greatest regional blood flow and glucose metabolic rate increases indicate that direct CNS effects of vinpocetine should be considered as an explanation for the therapeutic effects. The confirmation of this suggestion requires further investigations. 相似文献