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31.
Inflammation Research - 相似文献
32.
The eyes of a 72-year-old woman with a history of two branch retinal vein occlusions involving the left eye, were obtained postmortem and studied histopathologically. Prior to her death, she had been enrolled in the multicentered, prospective, randomized clinical trial on branch vein occlusion and treated with peripheral argon laser photocoagulation for disc neovascularization. Routine fluorescein angiograms and fundus photographs were available for clinical correlation. Despite photocoagulation, the patient had frequent recurrent episodes of vitreous hemorrhage. On histologic examination, both venous occlusions were found at arteriovenous crossings and associated with moderately sclerotic retinal arterioles. One occlusion was recanalized. Retinal inner ischemic atrophy was observed distal to the site of both venous occlusions and corresponded to areas of nonperfusion. Cystoid macular edema was not present. Three areas of neovascularization were found; one at the optic nerve head, one at the peripapillary retina, and one at the fovea. It is likely the patient's repeated vitreous hemorrhages were from one or all three areas of neovascularization demonstrated histopathologically. 相似文献
33.
Claus Zimmer Stefanie Märzheuser Stephan Patt Arndt Rolfs Joachim Gottschalk Klaus Weigel George Gosztonyi 《Journal of neurology》1992,239(7):394-400
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment. 相似文献
34.
The lateral vastus muscle flap has the potential to become one of the most appropriate free flaps for reconstructive surgery in the oral maxillofacial area in selected cases. The flap is relatively easy to harvest and gives rise to little donor site morbidity. The quality of the large diameter vessels allows for relatively easy microsurgical anastomosis. Nerve anastomosis is possible, which makes it extremely suitable for tongue reconstruction. 相似文献
35.
Summary. Max Br?del (1870–1941), from Leipzig, Germany, is often referred to in the USA as the father of modern medical illustration
and mentioned in the same breath as Leonardo da Vinci or Andreas Vesal. After a classical formal art education in Leipzig
he worked in Carl Ludwig's laboratory of physiology and anatomy, where he came in contact with American physicians. In 1894,
the anatomist F. P. Mall convinced him to work for the recently inaugurated Johns Hopkins School of Medicine in Baltimore,
where he collaborated with world-famous surgeons such as H. A. Kelly, W. S. Halsted, and H. Cushing. His illustrations were
characterized by meticulous observation, both realistic and explanatory intention, technical superiority, and artistic merit.
In 1911 he established the first “Department of Art as applied to Medicine”. Here, he proved to be an innovative artist, a
creative scientist, and an inspiring and skillful instructor. By the time of Br?del's retirement in 1939, 160 students had
graduated as medical illustrators. His pupils spread his principles and style throughout the USA and Canada, and several similar
academic programs for medical illustration have been founded in these countries.
相似文献
36.
Gudrun Bornh?ft Stefanie Maxion-Bergemann Ursula Wolf Gunver S Kienle Andreas Michalsen Horst C Vollmar Simon Gilbertson Peter F Matthiessen 《BMC medical research methodology》2006,6(1):56
Background
It is often stated that external validity is not sufficiently considered in the assessment of clinical studies. Although tools for its evaluation have been established, there is a lack of awareness of their significance and application. In this article, a comprehensive checklist is presented addressing these relevant criteria. 相似文献37.
Dermatitis in bulb growers 总被引:2,自引:0,他引:2
Derk P. Bruynzeel Edith M. de Boer Elly J. Brouwer Frederik A. de Wolff Peter de Haan 《Contact dermatitis》1993,29(1):11-15
A damaged skin forms a health hazard in flower-bulb growers as it enables higher permeation rates For pesticides than normal skin. Therefore, an investigation was performed into the skin condition of 103 bulb growers and 49 controls. Contact dermatitis of the hands was of the same order (11 and 10%) in both groups. However, minor signs of dermatitis were seen more often in bulb growers (30 versus 8%, p <0.05). Most growers had contact with narcissus sap during the investigation. This irritant sap, as well as many other skin contacts with irritants such as hyacinth dust and pesticides, seemed to be responsible for many skin complaints. Contact serialization was suspected in 19 growers and 3 controls. Patch tests showed that contact sensitization existed to pesticides in probably 10, and to flower-bulb extracts in 4 growers. Reactions to propachlor were not regarded as very reliable as the test concentration seemed to be marginally irritant. There were only a few allergic reactions to narcissus (3) and tulip (2) and none to hyacinth. This investigation showed that minor irritant contact dermatitis was frequent in bulb growers, and indicated that contact sensitization to pesticides and bulbs seemed to be a less frequent but important cause of dermatitis. 相似文献
38.
Bernhard J. Connemann Heidrun Busche Jürgen Kreusch Helmut H. Wolff 《Skin research and technology》1996,2(1):40-48
Background/aims: Quantitative measurement of skin roughness has proved to be a valuable tool in the efficacy-control of external applications, but it suffers from not yielding easily comparable results. The most important sources of inter-observer variability are high-pass filters used to separate roughness and waviness, and low-pass filters which result from the finite resolution of the instrument or from the finite sampling interval of digital measurement. In the present study, the effects of high-pass filters and sampling intervals on the roughness measured were investigated. Methods: Dynamically focusing optical profilometry was used to measure the surfaces of negative replicas of healthy human skin. High-pass cut-off wavelengths and sampling intervals were varied systematically. Results/conclusions: Virtually unbiased estimates for the roughness parameters K, Sk, Rq, and Ra can be obtained using sampling intervals of 40 or even 80 μm. Regarding these roughness parameters, it is far better to do more scans than to shorten the sampling interval. The roughness parameters Rz, Rp, Rt, Rpm, Rmax, Pt, on the other hand are very sensitive to the influence of the sampling interval; to achieve satisfying estimates, the sampling interval should be no longer than 2 to 5 urn; as an important parameter’of the measurement, it is worthy of remark and should always be indicated. The way the mean square roughness Rq depends on the cut-off wavelength is not well described by the Sayles-Thomas-relation Rq~λc0.5. If the power-spectrum |h*(v)|2 approximates sufficiently to a power law, |h*(v)|2~vδ, a better estimate is given by Rq~λcγ with γ=-(δ+1)/2. In many cases, γ=1 or Rq~λc will suffice. 相似文献
39.
40.
Sylvia Czapla Ralf Ruhmann Joachim Rübner Veit Zschuppe Dietmar Wolff 《Macromolecular chemistry and physics.》1993,194(1):243-250
The synthesis and characterization of new poly({6-[4-(4-cyanophenylcarbamoyl)phenoxy]hexyl methacrylate}-co-{6-[4-(4- cyanophenylazo)phenoxy]hexyl methacrylate}) are reported. Their liquid-crystalline properties are investigated using differential scanning calorimetry, polarizing microscopy and X-ray diffraction techniques. The glass transition temperatures and the clearing points can be influenced by variation of the copolymer composition. The substances offer a relatively broad temperature range of mesomorphic properties suitable for photochemical studies. 相似文献