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Mamas A. Mamas PhD BM BCh Farzin Fath‐Ordoubadi MD BM BChir Douglas G. Fraser MD BM BChir 《Catheterization and cardiovascular interventions》2010,76(1):102-111
Failure to deliver stents is one of the commonest causes of procedural failure in contemporary PCI practice. We describe successful use of the Guideliner Catheter, the first purpose designed FDA and CE marked device delivery catheter in 13 complex cases in native coronary vessels and bypass grafts performed via the radial route to enable distal stent delivery following failure of conventional techniques. We discuss how the Guideliner catheter may be used to facilitate difficult radial cases. © 2010 Wiley‐Liss, Inc. 相似文献
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Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting. 相似文献
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Summary
Background. The histogenesis of pancreatic cancer is still debatable. Ductal, ductular, and acinar cells all have been declared the tumor
progenitor cells. Our long-term human and experimental studies indicate that pancreatic ductal adenocarcinomas arise within
ductal cells and islets. Supporting studies are presented in this article.
Methods. Several human studies and experimental studies on Syrian hamsters conducted within the last 20 years were used in this article.
Hamster and human islets were established, and their growth and morphologic changes were examined electron microscopically,
immunohistochemically, cytogenetically, and molecular biologically.
Results. Studies using the hamster pancreatic cancer model showed that most pancreatic adenocarcinomas develop within islets, most
probably from stem cells, which are also believed to be the progenitor cells for tumors that develop within ducts. Studies
in newly established human and hamster islets culture validated the immense potential of islet cells to differentiate and
become malignant. The higher susceptibility of islet cells to become malignant could be related to their high drug-metabolizing
enzymes and their high proliferation rate. Dietary studies indicate that the promoting effect of a high-fat diet on pancreatic
carcinogenesis is unrelated to the energy intake, but rather is related to its effect on islet cell replication.
Conclusion. Experimental and human studies during 20 years of research in our laboratories point to the importance of pancreatic
islets in the development of ductal-type adenocarcinomas. We believe that pancreatic cancer that develops within ducts, but
more frequently within islets, derives from pancreatic stem cells that are distributed within the ductal trees and within
the islets
The data was presented at the 8th meeting of the International Association of Pancreatology, as the IAP Founder’s Lecture
July 14, 1998 in Tokyo, Japan. 相似文献
108.
G. Purcell-Jones BSc MRCP FFARCS F. Dormon MB BS FFARCS Registrars E. Sumner BM BCh FFARCS Consultant 《Anaesthesia》1987,42(12):1316-1320
This is a retrospective study on the use of postoperative opioids in neonates admitted to the surgical intensive care unit at Great Ormond Street over a 5-year period (1980-84). A total of 131 (14%) babies received opioids out of 933 neonates admitted to the unit. The use of opioids increased from 9.7% to 27.2% of admitted cases during the survey period. Postoperative ventilation of the lungs was necessary in 240 (25.7%) cases and 88 (36.6%) of these were given opioids. Four babies initially failed to wean from controlled ventilation as a result of opioid induced respiratory depression. A total of 51 (7.35%) spontaneously breathing neonates received opioids and seven (13.7%) of these developed apnoea or respiratory failure thought to be induced by opioids. The administration of opioids by nurses occurred most frequently in the late evening and early hours of the morning, when medical cover is at its lowest level. 相似文献
109.
Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma. 相似文献
110.