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21.
Antibody Conjugates for the Treatment of Cancer 总被引:3,自引:0,他引:3
22.
23.
Geoffrey G Hallock 《CANADIAN JOURNAL OF PLASTIC SURGERY》2003,11(2):67-69
The use of the radial artery as an alternative vascular conduit for coronary bypass surgery has become increasingly popular. The plastic surgery experience with radial forearm flaps has shown that sacrifice of the radial artery is not always a benign maneuver. The potential morbidity after using this conduit donor site in terms of hand dysfunction or wound healing problems can be significant, and frequently must ultimately be addressed as part of the role of the reconstructive surgeon. Case examples of skin necrosis, subsequent forearm wound infection and hypertrophic scarring after radial artery harvest are presented to introduce this as a real concern and to allow a review of the entire spectrum of potential problems in this regard. Any selection process where the radial artery may be chosen as the coronary revascularization conduit must anticipate these known donor site complications. 相似文献
24.
J. Thiele T. K. Zirbes J. Lorenzen H. M. Kvasnicka S. Scholz A. Erdmann U. Flucke V. Diehl R. Fischer 《Annals of hematology》1997,75(1-2):33-39
In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed
cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition
to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly
(PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML).
Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal
antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index
was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed
the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and
PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid
or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the
control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant
expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant
feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the
latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive
lesions extends previous experimental data on hematopoietic cell kinetics.
Received: 10 March 1997 / Accepted: 18 May 1997 相似文献
25.
L H Anderson T L McDonald G M Thiele L W Klassen 《Journal of clinical laboratory analysis》1992,6(3):113-118
Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells. 相似文献
26.
27.
Egidio L. Romano res Soyano Ramón F. Montaño Murray Ratcliffe Marilyn Olson Guillermo Suarez Nelly Martínez and Geoffrey Worstey 《Vox sanguinis》1994,66(3):194-199
Thirteen infants, 10 with A-O and 3 with B-O hemolytic disease of the newborn (ABO-HDN), were treated with synthetic A or B blood group trisaccharides (ATS, BTS) which cause dissociation of maternal antibody bound to infant red cells. The clinical outcome was compared with that of a control group of 21 infants treated with phototherapy during the preceding year. Exchange transfusion was required in 2 out of 13 infants in the experimental group and in 7 in the control group. A randomized prospective controlled study is necessary to confirm these results. 相似文献
28.
PURPOSE: To assess the consistency of ratings assigned by health sciences faculty members relative to community members during an innovative admissions protocol called the Multiple Mini-Interview (MMI). METHOD: A nine-station MMI was created and 54 candidates to an undergraduate MD program participated in the exercise in Spring 2003. Three stations were staffed with a pair of faculty members, three with a pair of community members, and three with one member of each group. Raters completed a four-item evaluation form. All participants completed post-MMI questionnaires. Generalizability Theory was used to examine the consistency of the ratings provided within each of these three subgroups. RESULTS: The overall test reliability was found to be .78 and a Decision Study suggested that admissions committees should distribute their resources by increasing the number of interviews to which candidates are exposed rather than increasing the number of interviewers within each interview. Divergence of ratings was greater within the pairing of community member to faculty member and least for pairings of community members. Participants responded positively to the MMI. CONCLUSION: The MMI provides a reliable protocol for assessing the personal qualities of candidates by accounting for context specificity with a multiple sampling approach. Increasing the heterogeneity of interviewers may increase the heterogeneity of the accepted group of candidates. Further work will determine the extent to which different groups of raters provide equally valid (albeit different) judgments. 相似文献
29.
30.
Transformation of Penicillium chrysogenum using the Aspergillus nidulans amdS gene as a dominant selective marker 总被引:5,自引:0,他引:5
Summary The Aspergillus nidulans acetamidase gene (amdS) has been used to transform Penicillium chrysogenum at low frequency. Several transformants were tested and shown to be mitotically stable. Southern blot analysis indicated that transforming DNA had integrated into the chromosomal DNA, possibly at multiple sites. 相似文献