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61.
An enantioselective synthesis of the (1'S,2'R)-dimethylheptyl cannabinoid side chain has been developed and employed in the synthesis of 11-hydroxy-(1'S,2'R)-dimethylheptyl-delta 8-THC (3). Pharmacology, in vivo and in vitro, indicate (3) to be one of the most potent traditional cannabinoids known. 相似文献
62.
JW Franks 《Canadian Metallurgical Quarterly》1998,24(9):989-993
BACKGROUND: Mounting specimens onto chucks, so the cryostat knife follows the exact path of the surgeon's knife, poses difficulties even for experienced histotechnologists. Oftentimes, the frozen planar surface of the tissue falls at an angle that requires gimballing the chuck holder to compensate. OBJECTIVE: To demonstrate the use of a precision tissue mounting machine and associated fast freezing chucks. METHODS: Specimens of pickled pig skin were marked with blue dye on the cut surface. The pieces were mounted onto chucks with the blue surface exposed, and then sectioned in a cryostat. RESULTS: A complete section with all edges was obtained after eight turns of the cryostat handwheel, at 12 microns per turn. CONCLUSIONS: A precision machine used in conjunction with a properly adjusted chuck holder can yield results unobtainable by other methods. 相似文献
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E Elstner M Linker-Israeli J Le T Umiel P Michl JW Said L Binderup JC Reed HP Koeffler 《Canadian Metallurgical Quarterly》1997,99(2):349-360
Patients with acute promyelocytic leukemia (APL) usually relapse after all-trans retinoic acid (RA) treatment because this therapy fails to eradicate the malignant clone. Our data showed that KH 1060 and other 20-epi vitamin D3 analogs alone were potent inhibitors of clonal growth of NB4 cells, an APL cell line (ED50, approximately 5 x 10(-11) M). The combination of KH 1060 and 9-cis-RA synergistically and irreversibly enhanced this effect. Neither KH 1060 nor 9-cis-RA (10(-6) M, 3 d) were strong inducers of differentiation of NB4 cells. However, 98% of the cells underwent differentiation to a mature phenotype with features of both granulocytes and monocytes after exposure to a combination of both compounds. Apoptosis only increased after incubation of NB4 cells with 9-cis-RA alone (28%) or with a combination of 9-cis-RA plus KH1060 (32%). Immunohistochemistry showed that the bcl-2 protein decreased from nearly 100% of the wild-type NB4 cells to 2% after incubation with a combination of KH 1060 and 9-cis-RA, and the bax protein increased from 50% of wild-type NB4 cells to 92% after culture with both analogs (5 x 10(-7) M, 3 d). Western blot analysis paralleled these results. Studies of APL cells from one untreated individual paralleled our results with NB4 cells. Taken together, the data demonstrated that nearly all of the NB4 cells can be irreversibly induced to differentiate terminally when exposed to the combination of KH 1060 and 9-cis-RA. 相似文献
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One way hospitals complicate themselves is by increasing the participation of clinical professionals and middle managers in making strategic decisions. Using a survey methodology this article investigates the relationships between the participation of clinical professionals (MDs and RNs) and middle managers with hospital costs, as well as the possible moderating effect of strategic complexity. 相似文献
68.
Adhesive interactions between leukocytes and endothelium are required for subsequent leukocyte extravasation toward inflammatory sites. Understanding the possible kinetic expression of vascular cell adhesion molecule-1 (VCAM-1) in the middle ear cavity during an inflammatory cascade in vivo may be important for clarifying local immunological responses in otitis media. Two inflammatory models were produced in the rat and involved acute middle ear mucosal and cutaneous inflammation induced after inoculation or intradermal injection of lipopolysaccharide (LPS). After intravenous injection of both 125I-labeled anti-VCAM-1 and 131I-labeled control monoclonal antibody (mAb), the kinetic expression of VCAM-1 in the middle ear and skin was assessed by local radionuclide uptake. The biodistribution of an 125I-labeled anti-VCAM-1 mAb as a potential detector of focal inflammation was examined in normal rats. Both inflammatory lesions were characterized by early and sustained (up to 24 h) expression of VCAM-1, with maximal expression at 4 h after LPS stimulation. The kinetics of VCAM-1 expression was similar among the middle ear mucosa or skin specimens studied and different stimulation methods. A similar biodistribution and clearance of radioactivity between 125I-labeled anti-VCAM-1 mAb and 131I- or 99mTc-labeled control mAb were observed. The present result suggest that functional VCAM-1 induced by LPS is expressed in both middle ear tissue and skin lesions and may play a role in the initial stage of inflammatory response produced. Although VCAM-1 upregulation is a very early event in the inflammatory cascade, 125I-labeled anti-VCAM-1 mAb may be useful for the early detection of focal inflammation in the middle ear. 相似文献
69.
JW Brufsky D Ross-Degnan D Calabrese X Gao SB Soumerai 《Canadian Metallurgical Quarterly》1998,36(3):321-332
Three receptor tyrosine kinases of the PDGF receptor family (RTKP) that clustered within 1000 Kb of the mouse chromosome 5 constitute an interesting unit that are expressed in three distinct cell lineages essential for constructing hematopoietic tissues. Namely, the c-kit gene that is expressed in hematopoietic stem cells is flanked by pdgfr alpha and flk genes expressed respectively in stromal cells and vascular endothelial cells. In this article, we review our results on their expression in the embryonic hematopoietic tissues. We found that co-expression of Flkl and c-Kit was frequently detected either in vascular endothelial cells or hematopoietic cells in the early hematopoietic tissues. On the other hand, the three RTKPs are expressed in different cell lineages in the fetal liver. On the basis of this finding, we propose two modes of embryonic hematopoiesis; hematogenic angiopoiesis and hematopoiesis. 相似文献
70.
MJ Telford JW Martin BJ Rock LL Turik JE Hairfield 《Canadian Metallurgical Quarterly》1994,19(3):25-9, 33
Small local chapter groups can present quality cost effective regional seminars. Key components are dedication of members, teamwork, and a sense of direction. The following guidelines and information can provide a framework for planning and coordinating a seminar. 相似文献