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K-1735 clones 10 and M2 are cell lines cloned from a UV-induced murine melanoma. While both lines are highly tumorigenic, only the M2 cells are highly invasive in vitro and metastatic in vivo. Here we have exposed the clone 10 cells to the synthetic peptide PA22-2, which contains the IKVAV sequence from the A chain of laminin and which, like laminin, induces collagenase IV production and enhances metastasis formation by B16F10 cells. Zymogram analysis of conditioned media from clone 10 cells cultured on the peptide demonstrated a dose-dependent increase in collagenase IV activity. When clone 10 cells were cultured on a reconstituted basement membrane (Matrigel), this peptide caused an invasive phenotype comparable to the M2 cells. The invasive clone 10 cells were, however, unable to form lung colonies in vivo in the presence of this peptide. We conclude that this peptide represents an active site on laminin which is able to stimulate the invasiveness of this tumor cell line, but that this activity is not sufficient to confer metastatic potential.  相似文献   
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A 73-year-old woman was studied after admission for anteriorwall ST-segment elevation myocardial infarction. Transthoracicechocardiography (GE Vingmed, Vivid 7, Horten, Norway)  相似文献   
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AIMS: To determine the morbidity, mortality and healthcare costs of intravenous drug-abusing patients with Type 1 diabetes (IVDA-DM), who are admitted to hospital. METHODS: Retrospective case note analysis of admissions, complications and cost estimation over a 6-year period. Each drug-abusing patient (IVDA-DM) (n = 9) was compared with two controls (n = 18) with Type 1 diabetes but without a history of intravenous drug abuse (DM-controls). Admissions were also analysed for patients with intravenous drug abuse, but without Type 1 diabetes (IVDA-controls) (n = 198). Admissions were at a University teaching hospital in Liverpool, UK. DM-controls were drawn from a population attending diabetes outpatient clinics between 1997 and 2002 at the same hospital. The main outcome measures were: the duration and healthcare costs of hospital admissions per year, outpatient attendances per year, glycated haemoglobin (HbA(1c)), weight, micro- and macrovascular complications and mortality. RESULTS: Multiple admissions, mainly related to ketoacidosis, led to marked differences in mean (95% CI) inpatient days per year per patient [IVDA-DM 28.1 (13.6-42.7) vs. DM-control 1.1 (0.2-1.9); P < 0.0001], mean inpatient days per year per patient in critical care bed (IVDA-DM 1.7 (-0.7-4.2) vs. DM-control 0; P < 0.02) and mean costs of admission, per patient per year (pound sterling 7320 vs. pound sterling 230). The IVDA-DM group frequently omitted insulin, were underweight, failed to attend as outpatients and five had died by the end of 2002. The IVDA-controls spent considerably less time in hospital [3.4 (2.8-3.9) days per patient per year]. CONCLUSION: IVDA-DM patients have higher rates of diabetes complications, are admitted more frequently and have a high mortality compared with DM and IVDA-controls. The cost of inpatient care of this small group of patients was considerable.  相似文献   
157.
A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate.  相似文献   
158.
Tissue microarrays (TMA) consist of up to 1000 cylindrical tissue cores from different donor paraffin blocks relocated into one recipient block, allowing for efficient histopathological studies by fluorescence in situ hybridization, RNA in situ hybridization or immunohistochemistry. On the background of the increasing interest of the TMA technique in cancer research and the suggestion of its application also in studies of non‐neoplastic intracranial disorders, the technique was applied to pathologic white matter in AD brains. Eight cases with AD and concomitant white matter pathology were neuropathologically diagnosed on whole brain coronal slides. The TMA technique was used to grade severity of white matter pathology and to quantify small vessels with traditional staining and immunohistochemical markers. These measurements were compared with the whole brain neuropathological assessment. The technique produced good results with preserved tissue structures as confirmed by the whole brain evaluation. Severity of white matter pathology evaluated on the TMA cores correlated negatively with small vessel quantities, and statistically significant differences in vessel quantities paralleled different grades of white matter pathology. It is concluded that the TMA technique could be further utilized in studies of dementing disorders, and may have its advantages in large, clinically well‐characterized materials (e.g. in quantitative mapping of white matter changes).  相似文献   
159.
PURPOSE:. To compare the efficacy of endoscopic erbium:YAG laser goniopuncture in glaucoma treatment to trabeculectomy, both methods as adjuncts to cataract surgery. METHODS:. Fifty-nine eyes of 59 glaucoma patients with coexistent cataract were treated by phacoemulsification and endoscopic Er:YAG goniopuncture in a combined fashion. The primary study endpoints were intraocular pressure (IOP), number of antiglaucomatous drugs, postoperative complications, hospitalisation time and visual acuity at 1 year after surgery. To date, 24 eyes have finished the 1-year follow-up. This prospective treatment arm was compared to a retrospective inclusion-matched control group treated by trabeculectomy and cataract surgery in a single procedure. RESULTS:. In the laser-treated group, the mean IOP dropped by 30% from 23.4+/-3.7 mmHg to 16.3+/-6 mmHg ( P<0.0001) after 12 months. Without reoperation, treatment was successful in 71% of these eyes. In the control group, the IOP decreased by 33.5% from 22.7+/-3.3 mmHg to 15.1+/-3.8 mmHg ( P<0.0001). The success rate without reoperation was 46%. The number of antiglaucomatous drugs needed decreased from 1.48+/-0.95 to 0.48+/-0.7 ( P<0.0001) in the laser-treated group and from 2.0+/-0.9 to 0.39+/-0.6 ( P<0.0001) in the control group. Postoperative complications were found more frequently in the control group ( P<0.0001). Hospitalisation was shorter in the laser group ( P<0.0001). Postoperative visual acuity was lower in the control group ( P=0.004). CONCLUSION:. Combined Er:YAG goniopuncture and cataract surgery lowers the IOP to an extent comparable to combined trabeculectomy and cataract surgery. Due to fewer postoperative complications, Er:YAG goniopuncture seems to be superior to standard fistulation surgery as the primary approach within the first year.  相似文献   
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