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21.
A small-for-dates male infant with mental retardation, microcephaly, malformed ears, preauricular sinuses, epicanthal folds, micrognathia, congenital heart diseases, micropenis, and micropolygyria of the parietal and occipital lobes of the cerebral cortex was shown to have a 47,XY,+22 karyotype by trypsin-giemsa banding. Review of reported cases confirms that there may be distinctive trisomy 22 syndrome.  相似文献   
22.
Epithelioid hemangioendothelioma is a rare vascular tumor of bone. Between 1987-1999, seven cases of epithelioid hemangioendothelioma were recorded. The histopathological evaluation was done with hematoxylin and eosin stain and immunohistochemical stains along with the analysis of clinical data and X-ray findings. There were 4 males, 3 females between 15 to 48 years of age with complaints of pain and swelling. Long bones were involved in five of the seven patients and one was multifocal. Radiologically all seven patients showed osteolytic lesions. The histologic hall mark was the presence of eosinophilic, epithelioid cells with intracytoplasmic vacuoles. The tumor may be histologically confused with metastatic carcinoma, chondromyxoid fibroma and osteogenic sarcoma. Immunohistochemical reactivity was as follows: Vimentin (6/6 cases), Factor VIII related antigen (4/6 cases), Ulex Europeaus (5/6 cases), CD31 (3/5 cases), CD34 (3/5 cases), epithelial membrane antigen (1/6 cases), cytokeratin (none). Treatment comprised curettage (4 cases), wide excision (2 cases), below knee amputation (1 case) and post operative radiotherapy (2 cases). At follow-up, (available in 4 patients) two were without disease at 18 months and 120 months. Of the remaining two, one developed local recurrence after 36 months; while the other died of lung metastasis (18 months). A lytic bone shadow, the presence of plump eosinophilic often vacuolated cells on a myxoid background and immunohistochemistry together help in the correct recognition of this tumor.  相似文献   
23.
Cross-reactions in cell mediated immunity induced by atypical mycobacteria   总被引:1,自引:0,他引:1  
Cross-reactivity in the delayed hypersensitivity response to mycobacteria of different Runyon groups was tested in Swiss white mice immunised with live mycobacteria. All the strains tested gave cross-reactions and, generally, slow growers gave stronger cross-reactions with other slow growers than with rapid growers and vice versa. Sonicates of cross-reacting mycobacteria were also tested for their ability to generate activated macrophages in mice immunised with Mycobacterium avium. All the mycobacterial sonicates generated activated macrophages but a sonicate of Salmonella typhi did not. The sonicate of M. tuberculosis H37Rv also generated activated macrophages, which indicates that there might be protective cross-reactions between M. tuberculosis and atypical mycobacteria.  相似文献   
24.
The current study is carried out to find the in-vitro susceptibility of N. gonorrhoeae to Ciprofloxacin, Norfloxacin, Gentamycin etc. in 110 isolates obtained from acute gonococcal urethritis confirmed by smear examination. The isolates obtained are from the patients attending the Skin and STD Clinic of a teaching hospital, clinically diagnosed as suffering from acute gonococcal urethritis. Antibiotic susceptibility test was done by Kirby Bauer disc diffusion technique. Four to five similar well isolated colonies of the gonococcal strains were picked up with a wire loop and transferred to 5 cc of sterile trypticase soya broth (TSB). Tubes were incubated at 36 degrees C. GC agar base plates were inoculated with suspensions using a sterile cotton swab. Antibiotic discs were placed on these plates. The plates were incubated at 35 degrees C for 18-24 hours in a candle jar with 5-10% CO2. The plates were then observed to note the zones of inhibition around the discs. 87.27% of isolated strains were inhibited by norfloxacin at an MIC of 0.06 mu gm/ml; 89.08% of the strains were inhibited by ciprofloxacin at an MIC of 0.025 mu gm/ml. All the strains (110) were inhibited by ciprofloxacin at a concentration of 0.2 mu gm/ml. Gentamycin sensitivity was 86.36%. Out of 110 patients, 85 were treated with norfloxacin of which 81 (95.29%) were cured. Twenty five were treated with ciprofloxacin of which 24 (96%) were cured. This study shows high sensitivity of N. gonorrhoeae to norfloxacin and ciprofloxacin.  相似文献   
25.
In the present study, we describe the potential role of melatonin, a pineal hormone, in regulating the activation of the antigen-specific T cell response. Melatonin encouraged the proliferation of Th cells and improved their ability to secrete IL-4, but down-regulated the levels of IL-2 and interferon-gamma (IFN-γ). Melatonin, however, could not exert any influence on the T cells of unprimed mice. On studying the regulation of subclass of IgG isotype, melatonin specifically enhanced the secretion of antigen-specific IgG1 antibodies and decreased the yield of IgG2a isotype. The results suggest that melatonin possibly acts by selectively activating a Th2-like immune response.  相似文献   
26.
P-selectin inhibition suppresses muscle regeneration following injury   总被引:3,自引:0,他引:3  
This investigation sought to determine if P-selectin-mediated mechanisms contributed to macrophage localization in damaged muscle, an essential process for muscle regeneration. Mice were injected intravenously (i.v.) with soluble P-selectin glycoprotein ligand-1 (sPSGL-1) at 5, 50, or 200 microg/mouse or with 100 microl vehicle alone, and then, lengthening contractions were induced in hindlimb plantar-flexor muscles. The contractions caused fiber damage in soleus muscles, with maximal invasion by CD11b+ mononuclear cells at 24 h post-injury and substantial accumulation of CD11b+ mononuclear cells in the extracellular matrix up to 7 days post-injury. sPSGL-1 treatment caused a dose-dependent decrease in the number of regenerating fibers (P=0.021), as determined by developmental myosin heavy chain (dMHC) expression. This expression was reduced 93% at 7 days post-injury by the highest dose of sPSGL-1, which had no significant influence on intrafiber or extracellular accumulation of cells expressing CD11b, a general marker for phagocytic cells. Additional mice were injected i.v. with 20 microg anti-P-selectin or isotype-control immunoglobulin G and were then subjected to lengthening contractions as before. At 7 days post-injury, soleus muscles from anti-P-selectin-treated mice contained 48% fewer mononuclear cells that bound ER-BMDM1 (P=0.019), a marker for mature macrophages and dendritic cells, and 84% fewer fibers expressing dMHC (P = 0.006), compared with muscles from isotype-injected, control mice. The number of CD11b+ cells was not significantly different between groups. The results are consistent with the concept that P-selectin is involved in the recruitment, maturation, and/or activation of cells that are critical for muscle fiber regeneration.  相似文献   
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29.
Four patients with unusual femoro-patellar chondral defects are presented. We were unable to find their particular lesion described adequately in the literature. The patients all gave a history of relatively minor non-contact injury and presented with anterior knee pain and persistent swelling. The main features on clinical examination were moderate effusion and marked patello-femoral crepitus. Plain X-rays of the knee were unhelpful. At arthroscopy large full thickness chondral defects were seen on the femoral side of the patello-femoral articulation at the site of patellar contact with the knee in about 60° of flexion. The synovium was found to be prolific and vascular. Multiple 1.6-mm drill holes were made in the defect and chondral debris was washed out. Two patients underwent associated lateral patellar release. When a clear cut mechanical patello-femoral disorder presents unexpectedly with associated effusion and a normal radiograph, we suggest that arthroscopy be advised with particular attention to the femoral trochlea.  相似文献   
30.
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