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991.
992.
Summary Thirty-eight human pancreatic cancer cases were examined by immunohistochemistry for expression of CA 19-9 and DU-PAN-2 antigens by the respective monoclonal antibodies. CA 19-9 was expressed in 82% and DU-PAN-2 in 87% of cases. A combination of two antibodies increased the reactivity to 97%. Six CA 19-9-negative cases were DU-PAN-2 positive and 4 DU-PAN-2-negative cases expressed CA 19-9. In only 1 case (an anaplastic carcinoma), neither of the antibodies was reactive with cancer cells. The reactivity of tumor cells with each of the antibodies varied from case to case, and, within the same tumor, from one area to another. Histologically, all but one tumor were adenocarcinomas. Thirty-five cases showed areas of either a moderate degree of differentiation (16 cases), poor differentiation (11 cases) or anaplastic areas (8 cases). Although both antigens were expressed in a greater number of cancer cells in well differentiated areas, and less frequently in poorly differentiated and anaplastic regions, the difference in antigen expression in relation to the degree of tumor differentiation was not statistically significant. The cellular localization of the antigens varied. DU-PAN-2 was primarily localized within the cytoplasm, whereas CA 19-9 was found mostly on the luminal cell surface and in luminal content of the glandular structure. In tumor-free pancreatic tissue, adjacent to the tumor, CA 19-9 was detected almost exclusively in the cells of large and medium sized ducts, whereas DU-PAN-2 was primarily expressed in terminal ductular and centrocinar cells. The results indicate that a cocktail of CA 19-9 and DU-PAN-2 antibodies could increase the likelihood of identifying a biomarker in most patients with pancreatic cancer.  相似文献   
993.
Balb/3T3 fibroblasts were cultured in type I collagen gel and the effects of tretinoin (all-trans-retinoic acid) were examined on cell growth and the gel contraction produced by cells. Cell proliferation was suppressed and the degree of gel contraction was enhanced by the addition of 10(-7) and 10(-6) M tretinoin. Growth and gel contractility of transformed cells derived from the Balb/3T3 cells were not influenced by this agent. Addition of 12-O-tetradecanoylphorbol ester, which is known to antagonize tretinoin in several biological processes, enhanced gel contraction synergistically with tretinoin. These results suggest that tretinoin influences cell-to-collagen interactions.  相似文献   
994.
995.
OBJECTIVES: It is well known that injection of calcitriol (CT) or maxacalcitol (OCT) is very effective in hemodialysis patients with secondary hyperparathyroidism (2HPT). However, it is difficult to use these drugs with peritoneal dialysis (PD) patients with 2HPT because these drugs must be injected two or three times per week. The objective of the present study was to evaluate the stability of physiological activities of CT and OCT in PD bags and to determine the CT or OCT dosage for intraperitoneal (IP) administration. MATERIALS AND METHODS: We added CT 1.5 microg or OCT 10 microg to Dianeal PD-2 (approximate pH = 5.0, calcium = 0.87 mmol/L; Baxter,Tokyo, Japan), Midpeliq 250 (approximate pH = 7.0, Ca = 1.0 mmol/L;Terumo Corporation, Tokyo, Japan), and Peritoliq 250 (approximate pH = 5.5, Ca = 1.0 mmol/L; Terumo Corp.). Dialysis solutions were collected from the PD bags at 0, 1, 4, 8, 12, 24, 48, and 72 hours after addition of CT and OCT. The activities of CT and OCT in the dialysis effluent were measured by radioimmunoassay. The levels of serum and effluent OCT after a single IP administration of 10 microg OCT were examined in 4 PO patients with advanced 2HPT. RESULTS: Although the levels of CT and OCT in PD bags made of polyvinyl resins decreased by 70% - 75% immediately after injection, levels in PD bags made of polypropylene resins decreased only slightly. The concentration of CT mixed into the acidic solution in glass containers was stable; the decreased concentration of CT in the PD solution might be due to adsorption onto polyvinyl resins. The maximum serum concentration after IP administration of 10 microg OCT was 750 pg/mL after 5 minutes, and remained at 500 pg/mL at 60 minutes. These results show good peritoneal transport of OCT but not rapid disappearance, unlike intravenous administration. CONCLUSIONS: If peritoneal administration of vitamin D derivatives is contemplated, it is important to select the composition of PD bag resins, type of vitamin D analog, and time lag to use when deciding the dosage of injectable vitamin D preparations, such as OCT or CT, for IP administration to PD patients. It appears that IP administration in overnight dwells might be useful for PD patients as a complementary vitamin D preparation.  相似文献   
996.
Eight cases of Ehlers-Danlos syndrome (EDS) were surveyed for clinical manifestations and orthopaedic treatment. Cases of EDS were clinically subdivided into three groups. The first group was characterized by multiple congenital contractures in the extremities, so that it was very difficult to distinguish it from arthrogryposis multiplex congenita in early infancy. Since laxity of the soft tissue coexists with contracture in this group, over-correction of deformity caused much more disability than under-correction, especially in clubfoot. Care should therefore be taken to avoid this. The third group was characterized by marked laxity of the soft tissue from birth. Diagnosis in this group was easily made by the obvious triad of EDS. Lengthy immobilization in an appropriate position was necessary to maintain a corrected position for the treatment of any deformity in the hip, foot or hand. In the second group, deformity and disability were clinically so mild that no orthopaedic management was generally required.  相似文献   
997.
998.
999.
In order to determine the localization of alpha 1-adrenoceptors in human hypertrophied prostates, in vitro autoradiography was performed on the frozen specimens from 13 enucleated hypertrophied prostates with [125I]-HEAT (iodo-2-[beta-(4-hydroxyphenyl)-ethylaminomethyl] tetralone) and [3H]-prazosin. In vitro autoradiograms showed macroscopically the specific binding site on the areas seemed to the nodular area for [125I]-HEAT, but not so clear specific binding sites for [3H]-prazosin. Microscopic autoradiograms seemed to show binding sites located mainly on the interstitial beneath the gland, and partly on the basement membrane and epithelium of the prostatic gland. Further studies are needed to show clearer specific binding sites of alpha 1-adrenoceptors.  相似文献   
1000.
An analog of diarylsulfonylurea, LY 186641 has a broad spectrum activity against murine solid tumors including Colon 26 and LX-1. Preclinical evaluation of the anticancer activity of LY 186641 using the subrenal capsule assay was performed in fresh human tumor samples derived from 87 patients with various cancers and 70 (80%) samples were evaluable. The overall chemosensitivity rate of LY 186641 was 37% and the average tumor growth inhibition rates (TGIRs) of malignant lymphoma, esophageal cancer and colorectal cancer were 51 +/- 19%, 51 +/- 20% and 48 +/- 12%, respectively. The antitumor effect obtained by LY 186641 was comparable to that of the standard anticancer drugs including adriamycin, 5-fluorouracil and cisplatin evaluated in this assay simultaneously. Based upon these results, LY 186641 is considered to have antitumor activity against some human cancers.  相似文献   
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