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901.
CM Gibson K Ryan A Sparano JL Moynihan M Rizzo M Kelley SJ Marble R Laham M Simons TR McClusky JT Dodge 《Canadian Metallurgical Quarterly》1999,137(1):169-179
It is unclear how agents designed to promote angiogenesis in the human heart affect the arteriographic appearance of the collateral circulation. Possible changes in collateral vessels include new collateral vessels arising from epicardial arteries, new branches emanating from existing collateral vessels, wider or longer collateral vessels, and higher dye transit rates that result in improved recipient vessel filling. Given the multiple mechanisms by which these new agents may improve myocardial perfusion, a rigorous, systematic, and comprehensive analysis of coronary arteriograms is required to discern the true mechanism of benefit. The method of analysis must account for potential changes in collateral blood flow, number, branching pattern, and length as well as changes in recipient vessel filling. The ability to detect differences between intricate networks of vessels in an angiographic study is dependent on maintaining consistency in cinefilming as well as the core laboratory methods between time points. In this report, we describe the methodology our angiographic core laboratory has found to be most effective to evaluate these very complex angiograms and attempt to capture all the possible modalities of angiogenesis. 相似文献
902.
Y Tanioka DE Sutherland Y Kuroda TR Gilmore TC Asaheim JW Kronson JP Leone 《Canadian Metallurgical Quarterly》1997,122(2):435-41; discussion 441-2
BACKGROUND: In islet transplantation pancreatic preservation before islet isolation is an obstacle compromising islet yield and viability. We tested the feasibility of a two-layer method (University of Wisconsin solution [UW]/perfluorochemical) for pancreatic preservation before islet isolation. METHODS: Dog pancreases were processed into pure islets by the method of Ricordi preceded by five different preservations (groups 1-a and 1-b, the two-layer method for 3 and 24 hours; groups 2-a and 2-b, simple cold storage in UW for 3 and 24 hours; group 3, without preservation). Islet yields and functional success after autotransplantation into the liver were compared among the groups. RESULTS: Postpurification islet equivalents (IE)/gm pancreas and functional success rate were 5600 (mean), 83% in group 1-a; 4000, 56% in group 1-b; 4700, 33% in group 2-a; 1300, 0% in group 2-b; and 5000, 89% in group 3 (p < 0.05; 2b versus 1-a, 1-b, and 3), respectively. There was no statistical difference among groups 1-a, 1-b, and 3 in terms of islet yield and function (p > 0.2). CONCLUSIONS: The two-layer method is more effective than conventional simple cold storage in UW for pancreatic preservation before islet isolation. Clinical trials with the two-layer method are warranted. 相似文献
903.
JC Byrd NS Dow E Gaertner JB Hargis TR Raber L Burrell RB Weiss 《Canadian Metallurgical Quarterly》1997,55(4):212-215
We report a patient with a history of T-cell ALL in remission who presented with symptoms and laboratory values consistent with subacute thyroiditis but was found to have leukemic thyroiditis as the first clinical manifestation of leukemic relapse. Bone marrow examination at this time demonstrated recurrent ALL. After successful re-induction with chemotherapy and an allogeneic bone marrow transplant this patient developed an isolated recurrence of her ALL manifested by symptomatic thyromegaly and a new mediastinal mass that was treated with irradiation. Despite no medullary recurrence of ALL, the patient developed pleuritic chest pain and shortness of breath and succumbed to pericardial extramedullary leukemia 9 months later. This to our knowledge is the third reported case of symptomatic ALL involvement of the thyroid gland and the first to be confirmed histologically. Furthermore, this patient had blast expression of the neural cell adhesion molecule (CD56), a cell surface marker that has not been studied in ALL but has previously been identified as a risk factor for extramedullary leukemia (EML) in acute non-lymphocytic leukemia. The authors hypothesize that CD56 expression in this patient might have contributed to her predisposition to EML. 相似文献
904.
The elasticity of a single supercoiled DNA molecule 总被引:3,自引:0,他引:3
TR Strick JF Allemand D Bensimon A Bensimon V Croquette 《Canadian Metallurgical Quarterly》1996,271(5257):1835-1837
905.
UR Rao C Nasarre SU Coleman M Bakeer VA Dennis DW Horohov TR Klei 《Canadian Metallurgical Quarterly》1996,82(3):255-266
The Brugia-jird model of lymphatic filariasis was used to examine the induction of cellular immune responses during the early premicrofilaremic phases of the infection. The intensity of the pulmonary granulomatous inflammatory response (PGRN) was determined by measuring granuloma areas around Sepharose beads coated with parasite extracts which were embolized in the lungs of jirds prior to necropsy. Necropsies were performed at 7, 14, 28, 56, and 150 days postinfection (DPI). These time points correspond to specific developmental changes in the life cycle. Lymphocyte blastogenesis assays were performed using cells from draining renal lymph nodes and splenocytes at 14 and 150 DPI. Soluble extracts of third stage larvae (L3), fourth stage larvae (L4), adult females, adult males, microfilariae (MF), and excretory secretory products (ES) of males and females were used in both measurements of cellular responsiveness. A marked granulomatous response to parasite extracts peaked at 7 DPI or 14 DPI followed by a gradual decrease to a hyporesponsive state at 120 DPI. The response of renal lymph node cells also was significantly elevated at 14 DPI and significantly decreased at > 150 DPI. The splenocyte responses were erratic and did not follow this pattern. Significant differences in PGRN responses to somatic extract preparations were not seen during the early stages of the infection (7, 14, 28 DPI), but those to MF and L3 were significantly less at 56 and 120 DPI. Although PGRN responses to ES followed a similar pattern, these were less than those to the somatic extract. The data indicated that a rapid, intense cell-mediated inflammatory response is induced early during a primary infection and that this response is rapidly downregulated. This downregulation begins prior to the maturation of adult parasites and microfilarial production. The early phase of the cellular response appears to be compartmentalized in that this response was consistently observed in the renal lymph nodes but not in the spleen. Soluble protein components of the parasites responsible for these responses are likely multiple and shared by all life cycle stages. 相似文献
906.
907.
908.
TR de Magalh?es ML de Magalh?es TR de Magalh?es Filho 《Canadian Metallurgical Quarterly》1996,44(3):101-103
The arrival of the Royal Family of Portugal in Brazil during the Napoleonic wars resulted in several changes in Brazilian society, as well as the founding of schools of medicine. The dental courses became independent with the imperial decrees of 1882 (Budget of the Empire) and 1884 (New Statutes of the School of Medicine) which are discussed. 相似文献
909.
910.
TR Chay 《Canadian Metallurgical Quarterly》1997,73(3):1673-1688
The extracellular calcium concentration has interesting effects on bursting of pancreatic beta-cells. The mechanism underlying the extracellular Ca2+ effect is not well understood. By incorporating a low-threshold transient inward current to the store-operated bursting model of Chay, this paper elucidates the role of the extracellular Ca2+ concentration in influencing electrical activity, intracellular Ca2+ concentration, and the luminal Ca2+ concentration in the intracellular Ca2+ store. The possibility that this inward current is a carbachol-sensitive and TTX-insensitive Na+ current discovered by others is discussed. In addition, this paper explains how these three variables respond when various pharmacological agents are applied to the store-operated model. 相似文献