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61.
Caroline S. Drugan rea Stone Steve M. Game Stephen S. Prime 《Journal of oral pathology & medicine》1997,26(7):327-333
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes. 相似文献
62.
We report on a man without any symptoms until the age of 29 years when a ventricular tachyarrhythmia occurred for the first time. There were electrocardiographic signs of a previous myocardial infarction of the anterior wall, but there had not even been any episode of angina pectoris. The cause was the anomalous origin of the left coronary artery from the pulmonary trunk (Bland-White-Garland syndrome). Therapy consisted of ligation of the left coronary artery and the implantation of an aortocoronary vein graft to the left coronary artery in order to reinstall a two-coronary system. Diagnosis is easily made by coronary angiography. At a 3-year follow-up there was an increase of the ejection fraction/cardiac output, a stable sinus rhythm, and an improved physical endurance. 相似文献
63.
A patient known with acute intermittent porphyria who developed primary liver-cell carcinoma is described. No other risk factors were found. A possible association of acute intermittent porphyria with the development of primary liver-cell carcinoma has been suggested in recent, mainly Scandinavian literature. So far this association has never been described in The Netherlands. 相似文献
64.
J E Meyer R L Christian T H Frenna M R Sonnenfeld E D Waitzkin K Shaffer 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(4):433-435
During the 30-month period from March 1, 1988, through August 31, 1990, image-guided aspirations of 183 solitary occult breast masses, which were considered possible cysts, were performed. Indications for aspiration included (1) mass on mammography, either invisible on ultrasonography or with features atypical of a cyst, in 111 patients; (2) enlarging solitary mass on mammography with ultrasonic features suggesting a cyst in 45 patients; and (3) mammographic mass with features typical of a cyst in 27 patients, with confirmation requested by the referring physician. Of the group, 151 (83%) lesions were fluid-filled and 32 (17%) were solid. All aspirates had normal cytologic features. Of the 32 aspirates found to be solid, 19 were subsequently removed after wire localization and 13 were unchanged on mammography for a minimum of 6 months after aspiration. This is a simple and safe procedure, confirming the innocuous nature of an occult solitary breast cyst, and obviates the need for surgical biopsy. 相似文献
65.
K Marsot-Dupuch B Meyer B Falisse P A Nicklaus C H Chouard 《Annales de radiologie》1992,35(1-2):44-49
Cochlear implantation is a treatment for profound bilateral cochlear hearing loss. Two broad varieties of cochlear implants are used: single or multichannel device (22- channel) inserted either into the cochlea (tympanic ramp) or on the promontory on round window Imaging modalities have to predict cochlear patency prior surgery, an essential factor for choosing between intra or extra cochlear implant. Since March 1991, we have investigated 23 implant candidates to evaluate cochlear patency prior surgery, 6 patients underwent surgery: 4 had a multichannel and 2 had a monochannel electrode. Both CT and MRI play a role in pre operative study. CT easily predicts cochlear ossification and labyrinthine malformations MRI (3 D applications) with T 2 Weighted images, one millimeter thick, more clearly depicts labyrinthine liquid and can predict cochlear fibrosis before ossification. 相似文献
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68.
Caroline Hartmann Hervé Récipon Marie-France Jubier Christiane Valon Evelyne Delcher-Besin Yves Henry Jacques De Buyser Bernard Lejeune André Rode 《Current genetics》1994,25(5):456-464
The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements. 相似文献
69.
70.
E. Nagel J. Jähne K. Obermann J. Lotz A. Meyer zu Vilsendorf R. Pichlmayr 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(1):29-32
In this retrospective study of 24 patients who were treated at our clinic during the last 22 years after having attempted suicide, we evaluated aspects concerning abdominal-and transplantation surgery. There was a predominance of “hard” (70%) versus “soft” (30%) methods for suicide attempt. Intra-abdominal injuries resulting from attempted suicide by stabbing or shooting should lead to laparotomy— the prognosis is then good. Surgical treatment after intoxication, especially caustic ingestion, depends on endoscopic and clinical findings. The highly increased rates of suicide significantly by kidney transplantation. The risk of suicide after transplantation is further diminished with improved immunosuppressive treatment. Only in a few cases there is an indication for liver transplantation— in some cases of fulminant hepatic failure caused by self-administered paracetomol overdose. Auxiliary liver transplantation may then be considered. 相似文献