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101.
Mario Perl Rolf E. Brenner Sabine Lippacher Manfred Nelitz 《Clinical orthopaedics and related research》2009,467(9):2472-2478
Dysplasia epiphysealis hemimelica (DEH) is a rare developmental disorder. The underlying pathophysiology is largely unclear.
Its diagnosis is based on clinical findings and may be difficult due to its low incidence and close relationship to other
disorders such as osteochondroma. We describe a 13-year-old boy who presented with a unilateral lesion of the left medial
femoral condyle and left ankle. In addition to standard diagnostic tools such as radiographs and MRI, arthroscopy-guided biopsy
was performed; histologic/immunohistochemical findings from cartilage-bone specimens confirmed the diagnosis and provided
novel information toward a disease mechanism. The cellular phenotype of clustered chondrocytes exhibited characteristics of
chondroprogenitor cells and terminally differentiated cells, suggesting dysregulation of resident progenitor cells. No other
surgery was performed and during a 2 year period, we observed spontaneous ossification of the lesion associated with decreased
joint impairment. Immunohistochemical analysis of the lesion provided a more accurate diagnosis and may contribute to unraveling
potential novel mechanisms involved in its pathogenesis.
Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest,
patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.
Each author certifies that his or her institution has approved the reporting of this case report, that all investigations
were conducted in conformity with ethical principles of research, and that informed consent for participation in the study
was obtained. 相似文献
102.
T J Masaryk J Perl R C Wallace M Magdinec D Chyatte 《AJNR. American journal of neuroradiology》1999,20(6):1103-1106
We describe a relatively unusual case of carotid cavernous fistula in association with a persistent trigeminal artery, presumably related to aneurysm rupture near the carotid origin of the vessel. We emphasize the use of a second, nondetachable balloon solely for the purpose of stabilizing placement of the first device at the time of detachment. 相似文献
103.
David N. Durrheim MPH TM MACTM Peter A. Leggat FAFPHM FACTM 《Journal of travel medicine》1999,6(3):172-179
BACKGROUND: One of South Africa's principal tourist attractions is the opportunity to encounter Africa's large mammals in the wild. Attacks by these mammals can be exceptionally newsworthy with potentially deleterious effects on tourism. Little is known about the risk of injury and death caused by wild mammals to visitors to South Africa's nature reserves. The aim of this study was to determine the incidence of fatal and nonfatal attacks on tourists by wild mammals in South Africa and to ascertain avoidable factors, if any. METHODS: Commercial press records covering all South African Newspapers archived at the Independent Newspapers' central library were systematically reviewed for a 10-year period, January 1988 to December 1997 inclusive, to identify all deaths and injuries to domestic and international tourists resulting from encounters with wild mammals in South Africa. All of these incidents were analyzed to ascertain avoidable factors. RESULTS: During the review period seven tourists, including two students from Thailand and a German traveler, were killed by wild mammals in South Africa. Three of the four deaths ascribed to lions resulted from tourists carelessly approaching prides on foot in lion reserves. A judicial inquiry found that the management of a KwaZulu-Natal Reserve was culpable for the remaining death. Tourist ignorance of animal behavior and flagrant disregard of rules contributed to the two fatalities involving hippopotami. The unusual behavior manifested by the bull elephant responsible for the final death, resulted from discomfort caused by a dental problem to this pachyderm. During the same period there were 14 nonfatal attacks on tourists, including five by hippo, three by buffalo, two by rhino, and one each by a lion, leopard, zebra and musth elephant. Only the latter occurred while the visitor was in a motor vehicle. Tourist ethological naivete and failure to determine the experience of trail guides prior to travel, resulted in inadvertent agonistic behavior, unnecessary risk-taking and avoidable injury. CONCLUSIONS: This retrospective study has shown that attacks on tourists by wild mammals in South Africa are an uncommon cause of injury and death. Sensible precautions to minimize this risk include remaining in a secure motor vehicle or adequately fenced precincts while in the vicinity of large mammals, rigidly observing nature reserve instructions, never approaching animals that appear ill, malnourished, displaying aggressive behavior traits or female wild mammals with young, and demanding adequately trained and experienced game rangers when embarking on walking trails. Any behavior that might be construed as antagonistic and which could provoke an attack by large mammals should be avoided (e.g., driving directly at a lion). Visitors need to be informed of classic signs of aggression, in particular in elephants, which will allow timely avoidance measures to be taken. The risk-enhancing effect of excessive alcohol intake is undesirable in the game reserve setting, as is driving at high speed after dusk in areas where hippos graze. Local advice on personal safety in wildlife reserves and the credentials of trail guides should be obtained from lodge or reserve management, tourism authorities or the travel industry prior to travel to game reserves. 相似文献
104.
TM Stein 《Canadian Medical Association journal》1999,160(13):1821-1821
105.
Ten anesthetized, paralyzed dogs were ventilated at 10 breath/min and 100 cycle/min with a valveless ventilator. When fresh respiratory gas was supplied at the carina or insufflated into the bronchi, there was a significant (p less than .05) reduction in PaCO2, which was maximal during high-frequency ventilation (HFV) with twice normal minute volume. There was no statistically significant advantage in using a more complicated system for bronchial insufflation compared with supplying the fresh gas through a single tube near the carina. The improvement in ventilation and oxygenation during HFV with gas at the carina was reduced markedly when normal lungs were injured by oleic acid. Thus, when peak airway pressure was minimized during HFV, there was a further improvement in gas exchange without an appreciable increase in airway pressure when the gas was supplied at the carina. 相似文献
106.
An immunocytochemical comparison of cytoskeletal proteins in aluminum-induced and Alzheimer-type neurofibrillary tangles 总被引:1,自引:1,他引:0
D. Munoz-Garcia W. W. Pendlebury J. B. Kessler D. P. Perl 《Acta neuropathologica》1986,70(3-4):243-248
Summary Exposure of the central nervous system (CNS) of rabbits to aluminum salts produces a progressive encephalopathy. Examination of CNS strucres discloses widespread perikaryal neurofibrillary tangle (NFTs) formation. The aluminum-induced NFTs consist of collections of normal neurofilaments, and differ ultrastructurally and in their solubility characteristics from Alzheimer-type NFTs, the latter being composed of largely insoluble paired helical filaments. The present study compares NFTs found in the rabbit to those of Alzheimer's disease, using monoclonal antibodies (SMI 31, SMI 32) that recognize phosphorylated and non-phosphorylated determinants respectively in normal neurofilaments, and an antiserum raised against purified microtubules. Paraffin-embedded sections were stained by the avidin-biotin immunocytochemical method. Intense staining of aluminum-induced NFTs was found after processing with SMI 31 and SMI 32, while no staining of non-tangled perikarya of control rabbits or of Alzheimer-type NFTs was seen. Antimicrotubule antiserum gave weak, nonfocal staining in the aluminum-treated and control rabbits, while Alzheimer-type NFTs were stained intensely. These results show that phosphorylated and non-phosphorylated neurofilaments accumulate in aluminum-induced NFTs, thus complementing the previously demonstrated specific slowing of the axonal transport of neurofilaments in aluminum intoxication. Further, they suggest that the presence of microtubular proteins may be necessary for altered neurofilaments to take on a paired helical configuration.Supported by NIH grant No. 1 KO8 AG00258 相似文献
107.
Carcinosarcomas are rare malignant biphasic tumours that contain intermingled carcinomatous and sarcomatous elements. Primary cutaneous carcinosarcomas (PCCS) are extremely rare. We present the 20th reported case and review the literature especially regarding histogenesis and clinical features such as diagnosis and management. PCCS resembles other non-melanocytic neoplasms of the skin. Diagnosis is obtained by primary excision with subsequent histologic and immunohistochemical examination. PCCS is a potentially lethal neoplasm, but radical surgery is successful in most cases. 相似文献
108.
The paper reports the determination of paracetamol in the serum by means of high-performance liquid chromatography. Prior to analysis, the sample is purified by deproteination with perchloric acid. The analysis is carried out isocratically on the reverse phase (SEPARON SIX C18, 5 microns, 150 x x 3.7 mm). The mobile phase consists of 40% methanol in 0.4% phosphoric acid. The detection is performed at 254 nm. The calibration curve is linear in the region 6.62-331 mumol.l-1 (1.0-50.0 micrograms.ml-1) with 95% reproducibility. The sensitivity of detection is 1.3 mumol.l-1 (0.2 microgram.ml-1). The suitability of the method was checked by processing 300 serum samples. 相似文献
109.
110.
Disease-free survival after autologous bone marrow transplantation in patients with acute myelogenous leukemia 总被引:1,自引:0,他引:1
Korbling M; Hunstein W; Fliedner TM; Cayeux S; Dorken B; Fehrentz D; Haas R; Ho AD; Keilholz U; Knauf W 《Blood》1989,74(6):1898-1904
Autologous bone marrow transplantation (ABMT) makes it possible to escalate the dose of cytotoxic treatment to a lethal range. Disease- free survival (DFS) following myeloablative therapy and ABMT has been shown to be superior to conventional treatment in high risk patients with acute myelogenous leukemia (AML). It was the purpose of the present study to compare hematopoietic reconstitution, actuarial DFS, and relapse rate of patients transplanted in first complete remission (CR) of AML with those in second or subsequent CR, and to evaluate transplant related mortality. Fifty-two patients with AML, 22 in first CR (low risk) and 30 in second or subsequent CR (high risk), underwent total body irradiation (12.1 to 16.7 Gy) and cyclophosphamide (CY) treatment (200 mg/kg) followed by ABMT. The autograft was incubated with the active CY derivative Mafosfamide (ASTA Werke, Bielefeld, Federal Republic of Germany) to reduce the number of possibly contaminating clonogenic tumor cells. All patients showed three lineage engraftments with platelet recovery observed as being the slowest. The transplant related death rate was low at 5.8%. There was no significant difference in the kinetics of polymorphonuclear (PMN) cell or platelet reconstitution between the low and high risk patient subgroups. The estimated probability of DFS (relapse) after ABMT in first CR was 61% (36%) compared with 34% (65%) in second or subsequent CR, the longest follow-up being 55 months and 57 months, respectively (median follow-up 31 months and 19 months, respectively). ABMT offers a stable long-term DFS when performed in first CR with no relapses occurring in over a year after transplantation. Six later relapses, however, were seen after ABMT in second or subsequent CR, although DFS was not statistically different from that of first remission patients (P = .72). 相似文献