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81.
BS Iyengar RT Dorr DS Alberts EM Hersh SE Salmon WA Remers 《Canadian Metallurgical Quarterly》1999,42(3):510-514
A set of 20 2-cyanoaziridine-1-carboxamides was synthesized from 2-cyanoaziridine and appropriate isocyanates. These compounds were active against a variety of solid and hematological tumor cells in culture, including strains resistant to doxorubicin and mitoxantrone. Their potencies in these assays correlated with the lipophilicity of substituents. The N-phenyl derivative was more potent and equally effective to imexon, a cyclized 2-cyanoaziridine-1-carboxamide of clinical interest, against cloned fresh human tumors. 相似文献
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ML Mayer SJ Clark TR Konrad VA Freeman RT Slifkin 《Canadian Metallurgical Quarterly》1999,89(2):164-170
OBJECTIVES: This study assessed the influence of public policies on the immunization status of 2-year old children in the United States. METHODS: Up-to-dateness for the primary immunization series was assessed in a national sample of 8100 children from the 1988 National Maternal and Infant Health Survey and its 1991 Longitudinal Follow-Up. RESULTS: Documented immunization rates of this sample were 33% for poor children and 44% for others. More widespread Medicated coverage was associated with greater likelihood of up-to-dateness among poor children. Up-to-dateness was more likely for poor children with public rather than private sources of routine pediatric care, but all children living in states where most immunizations were delivered in the public sector were less likely to be up to date. Poor children in state with partial vaccine replacement programs were less likely to be up to date than those in free-market purchase states. CONCLUSIONS: While state policies can enhance immunization delivery for poor children, heavy reliance on public sector immunization does not ensure timely receipt of vaccines. Public- and private-sector collaboration is necessary to protect children from vaccine-preventable diseases. 相似文献
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RA Wain GL Berdejo WN Delvalle RT Lyon LA Sanchez WD Suggs T Ohki E Lipsitz FJ Veith 《Canadian Metallurgical Quarterly》1999,29(1):100-7; discussion 107-9
PURPOSE: Arteriography is the diagnostic test of choice before lower extremity revascularization, because it is a means of pinpointing stenotic or occluded arteries and defining optimal sites for the origin and termination of bypass grafts. We evaluated whether a duplex ultrasound scan, used as an alternative to arteriography, could be used as a means of accurately predicting the proximal and distal anastomotic sites in patients requiring peripheral bypass grafts and, therefore, replace standard preoperative arteriography. METHODS: Forty-one patients who required infrainguinal bypass grafts underwent preoperative duplex arterial mapping (DAM). Based on these studies, an observer blinded to the operation performed predicted what operation the patient required and the best site for the proximal and distal anastomoses. These predictions were compared with the actual anastomotic sites chosen by the surgeon. RESULTS: Whether a femoropopliteal or an infrapopliteal bypass graft was required was predicted correctly by means of DAM in 37 patients (90%). In addition, both anastomotic sites in 18 of 20 patients (90%) who had femoropopliteal bypass grafts and 5 of 21 patients (24%) who had infrapopliteal procedures were correctly predicted by means of DAM. CONCLUSION: DAM is a reliable means of predicting whether patients will require femoropopliteal or infrapopliteal bypass grafts, and, when a patient requires a femoropopliteal bypass graft, the actual location of both anastomoses can also be accurately predicted. Therefore, DAM appears able to replace conventional preoperative arteriography in most patients found to require femoropopliteal reconstruction. Patients who are predicted by means of DAM to require crural or pedal bypass grafts should still undergo preoperative contrast studies to confirm these results and to more precisely locate the anastomotic sites. 相似文献
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In this paper the sequence specificity of DNA damage has been determined for 11 cisplatin analogues. A number of the analogues used in this study have been included in clinical trials. A Taq DNA polymerase linear amplification technique was utilised to ascertain the sequence selectivity of cisplatin analogues damage to DNA. The analogues differed in their ability to damage DNA with cisplatin being the most effective DNA damaging agent followed by (in decreasing order): tetraplatin (tetrachloro(1,2-diaminocyclohexane)platinum(IV) (RR isomer)), cis-dichlorobis(isopropylamine)platinum(II), dichloro(1,2-diaminocyclohexane)platinum(II) (SS isomer), dichloro(1,2-diaminocyclohexane)platinum(II) (RR isomer), cis-bis(cyclohexylamine)dichloroplatinum(II), carboplatin, cis-dichlorobis(isopentylamine)platinum(II), and CHIP (cis-dichloro-trans-dihydroxybis(isopropylamine)platinum(IV)). However, the sequence specificity of these analogues was similar in position and relative intensity of damage. We also provide evidence that platinum(IV) complexes can damage DNA without being reduced to platinum(II). It was found that a 10-fold higher concentration of cisplatin was required to damage DNA in Tris-HCl compared to Hepes buffers. In this paper we have detected a characteristic pattern of damage with monofunctional analogues that could be used to determine the mode of binding of a cisplatin analogue with DNA. The monofunctional analogues tested were chloro(diethylenetriamine)platinum(II) and cis-diamminechloro(1-octylamine)platinum(II) as well as transplatin. 相似文献
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In vitro studies have shown that gastroenteropancreatic tumors, with the exception of insulinomas, have a high density of somatostatin receptors and can be imaged in vivo using somatostatin receptor scintigraphy (SRS) with either [123I-Tyr3]octreotide or [111In DTPA,DPhe1]octreotide. However, the sensitivity in relation to conventional imaging studies (ultrasound, CT, MRI, angiography) remains unclear. To address this question, we performed a prospective study of 80 patients with gastrinomas where SRS was compared with other conventional imaging techniques for detecting extrahepatic gastrinomas or liver metastases. Extrahepatic gastrinomas were identified by SRS in 58 percent of patients, whereas conventional imaging studies detected gastrinomas in 9 percent to 48 percent of patients. In detecting hepatic metastases in 24 patients with histologically-proven metastases, SRS was positive in 92 percent; ultrasound, CT or angiography in 42 percent to 62 percent; and MRI in 71 percent of patients. These results are compared with other studies in detecting gastrinomas as well as series including other PETs, excluding insulinomas, with insulinomas alone, and with carcinoid tumors. An analysis of the ability of SRS to identify gastrinomas found in different sites at surgery was performed. The role of endoscopic ultrasound (EUS) in detecting various PETs, in comparison to that of SRS, is yet to be established, particularly for extrapancreatic PETs. Therefore, the results of EUS in various studies containing patients with PETs are compared to those with SRS and conventional imaging studies. These data suggest that EUS is the first choice of localization methods for detecting insulinoma, which is an intrapancreatic tumor in almost all cases. In other PETs there still is not sufficient data to establish the relative roles of EUS and SRS. 相似文献