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排序方式: 共有492条查询结果,搜索用时 140 毫秒
51.
Eight patients with the diagnosis of lymphangiomyomatosis were evaluated with computed tomography (CT), chest radiography, and pulmonary function tests to determine the relationship between the extent of disease seen on imaging studies and functional status. Chest radiographic assessment included the subjective determination of disease extent and measurements of lung length and the arc of the right hemidiaphragm. Disease extent on CT scans was scored as a percentage of lung that was abnormal on the basis of visual assessment of the degree of cystic replacement of the lung parenchyma. Significant correlations were observed between CT scores and percentages of predicted forced expiratory volume in 1 second/forced vital capacity (r = -.92, P less than .002) and diffusing capacity of the lungs for carbon monoxide (r = -.80, P less than .017). No significant correlations were observed between subjective chest radiographic scores and pulmonary function tests, although measurements of lung length and percentage of predicted total lung capacity were correlated (r = .76, P less than .045). CT was more accurate than chest radiography in defining the presence and extent of parenchymal cysts and provided for greater morphologic-physiologic correlation. CT, particularly high-resolution CT, may be useful in the diagnosis and longitudinal evaluation of patients with this disease and may be more sensitive than pulmonary function tests in the early stages of lung damage. 相似文献
52.
F Moureau J Wouters DP Vercauteren S Collin G Evrard F Durant F Ducrey JJ Koenig FX Jarreau 《European journal of medicinal chemistry》1992,27(9)
Toloxatone is a reversible MAOA-inhibitor, marketed as antidepressant (Humoryl®), with an original chemical structure. It differs from first generation irreversible MAOIs, known to induce covalent bonds with the enzyme active site. In order to understand the mechanism of the reversible inactivation of the MAO, as a first step, a detailed structural and electronic analysis was undertaken. An X-ray diffraction-crystallographic study showed that toloxatone is a planar molecule and brought to light hydrogen bonds and π-π interactions. MO calculations confirmed the planar structure as energetically favoured. Electronic analysis demonstrated a delocalization of both ring systems. The combined results give evidence for the potential of toloxatone to participate in reversible, long distance interactions with an appropriate partner. 相似文献
53.
54.
JKS Parihar SM DP Vats SM VSM RP Gupta TR Bera R Phooken A Singh 《Medical Journal Armed Forces India》2007,63(1):19-22
Background
Phaconit or ultra micro incision phacoemulsification cataract surgery involves phacoemulsification through a 0.9 millimetre sleeveless phaco tip and irrigating chopper followed by implantation of a rollable intraocular lens. The procedure leads to negligible astigmatism and faster visual recovery as compared to phacoemulsification with a foldable intraocular lens.Methods
This prospective study analysed 80 cases of sub millimetre phaconit surgery with implantation of rollable intraocular lenses(IOL) in 40 cases and acrylic foldable IOL in the remaining 40 cases. Evaluation of efficacy and adaptability of procedure, equipment settings, operative constraints, postoperative complications, keratometric and topographic evaluation of induced astigmatism with visual outcome and patient''s rehabilitation were studied.Results
The intraoperative complications were surge/ chamber collapse in 16 (20%), iris chaffing in one and corneal burns in two cases. All cases had an induced astigmatism of less than or equal to ± 0.25 D in four to six weeks after rollable IOL and ± 0.5 D to ± 0.75 D after acrylic IOL implantation. All patients had best-corrected visual acuity of 6/6 by third post operative day.Conclusion
Phaconit with rollable IOL is a perfect blend of surgical skill, application of technology and ultra thin IOL.Key Words: Phaconit, Ultra micro phaco, Submillimetre incision, Rollable IOL implantation 相似文献55.
目的:间充质干细胞具有强大的增殖能力和多向分化潜能,文章对其主要的来源途径予以综述。资料来源:应用计算机检索Medline1991-01/2006-01期间的相关文章,检索词为“mesenchyma stem cells,origin,research progress”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库1998-01/2006-10期间的相关文章,检索词为“间充质干细胞,来源,研究进展”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:①间充质干细胞的起源。②间充质干细胞研究进展、干细胞的分离及鉴定。排除标准:重复研究、个案报告或Meta分析类文章。资料提炼:共收集到96篇相关文献,40篇文献符合纳入标准,排除的56篇文献为内容陈旧或重复。符合纳入标准的40篇文献中,分别涉及骨髓、肌肉、脐血、胎盘、外周血、脂肪组织、血管及其他来源的间充质干细胞。资料综合:间充质干细胞是属于中胚层的一类多能干细胞,具有强大的增殖能力和多向分化潜能,动物模型试验和临床应用研究也取得了一定的效果。间充质干细胞来源广泛,易于获得,临床上为神经损伤及其他系统的损伤修复提供了更为广泛的途径。结论:间充质干细胞主要来源于骨髓、肌肉、脐血、外周血、胎盘等组织,具有广阔的应用前景。 相似文献
56.
Rapid mobilization of hematopoietic progenitor cells in rhesus monkeys by a single intravenous injection of interleukin-8 总被引:13,自引:6,他引:13
Laterveer L; Lindley IJ; Heemskerk DP; Camps JA; Pauwels EK; Willemze R; Fibbe WE 《Blood》1996,87(2):781-788
Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation. 相似文献
57.
58.
Nora Pashayan Paul DP Pharoah Johanna Schleutker Kirsi Talala Teuvo LJ Tammela Liisa M??tt?nen Patricia Harrington Jonathan Tyrer Rosalind Eeles Stephen W Duffy Anssi Auvinen 《British journal of cancer》2015,113(7):1086-1093
Background:
We derived estimates of overdiagnosis by polygenic risk groups and examined whether polygenic risk-stratified screening for prostate cancer reduces overdiagnosis.Methods:
We calculated the polygenic risk score based on genotypes of 66 known prostate cancer loci for 4967 men from the Finnish section of the European Randomised Study of Screening for Prostate Cancer. We stratified the 72 072 men in the trial into those with polygenic risk below and above the median. Using a maximum likelihood method based on interval cancers, we estimated the mean sojourn time (MST) and episode sensitivity. For each polygenic risk group, we estimated the proportion of screen-detected cancers that are likely to be overdiagnosed from the difference between the observed and expected number of screen-detected cancers.Results:
Of the prostate cancers, 74% occurred among men with polygenic risk above population median. The sensitivity was 0.55 (95% confidence interval (CI) 0.45–0.65) and MST 6.3 (95% CI 4.2–8.3) years. The overall overdiagnosis was 42% (95% CI 37–52) of the screen-detected cancers, with 58% (95% CI 54–65) in men with the lower and 37% (95% CI 31–47) in those with higher polygenic risk.Conclusion:
Targeting screening to men at higher polygenic risk could reduce the proportion of cancers overdiagnosed. 相似文献59.
Preparation of factor IX deficient human plasma by immunoaffinity chromatography using a monoclonal antibody 总被引:1,自引:0,他引:1
Goodall AH; Kemble G; O'Brien DP; Rawlings E; Rotblat F; Russell GC; Janossy G; Tuddenham EG 《Blood》1982,59(3):664-670
A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable from severe Christmas disease plasma and can be used as the substrate in a one stage coagulation assay for factor IX. The affinity column has high capacity and can be regenerated so that large scale production from normal plasma of factor IX deficient plasma as a diagnostic reagent is now feasible. 相似文献
60.
Alterations in neutrophil subpopulations during human hemodialysis or following injection of C5a des arg into rabbits were studied. Whereas baseline peripheral blood neutrophils contained approximately 80% of cells that formed rosettes with IgG-sensitized erythrocytes, neutrophils harvested at the granulocyte nadir (20 min after initiating hemodialysis or the injection of C5a des arg) were markedly depleted of this population. This was seen in a change in ratio of rosette-forming neutrophils (RFN) to non-rosette-forming neutrophils (non-RFN) from 4:1 at 0 time to 1:2 at 20 min. Since non-RFN are less active in assays of adherence and chemotaxis, these alterations in circulating neutrophil populations were reflected in abnormal functional capacity of neutrophils harvested at 20 min. To study the mechanism of RFN depletion, we investigated the ability of C5a des arg to aggregate various human neutrophil suspensions. Unfractionated neutrophils and RFN demonstrated prompt in vitro aggregation in response to C5a des arg, whereas this activated complement fragment induced little aggregation in a population enriched for non-RFN. These results may explain the alterations in neutrophil adherence, chemotaxis, phagocytosis, and bactericidal activity, which have been reported to accompany clinical disorders characterized by in vivo complement activation (i.e., hemodialysis or gram-negative sepsis). 相似文献