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911.
CH Kocken E Hundt B Knapp D Brazel B Enders DL Narum JA Wubben AW Thomas 《Canadian Metallurgical Quarterly》1998,66(1):373-375
Plasmodium falciparum antigens SERP, HRPII, MSAI, and 41-3 have shown promise as vaccine components. This study aimed at reproducing and extending previous results using three hybrid molecules. Antibody responses were reproduced in Aotus monkeys, but solid protection from a P. falciparum blood-stage challenge that showed an unintendedly enhanced pathogenicity was not observed. 相似文献
912.
OBJECTIVES: To evaluate the feasibility of and adherence to a nonpharmacologic sleep protocol targeted to nurses for acutely ill older patients and to test the effectiveness of the protocol on enhancing sleep and reducing sedative-hypnotic drug (SHD) use. DESIGN: Prospective cohort study. SETTING: A 34-bed general medical unit in a university-affiliated teaching hospital. PARTICIPANTS: A total of 175 consecutive admissions aged 70 years or older. INTERVENTION: A nonpharmacologic sleep protocol consisting of a back rub, warm drink, and relaxation tapes was administered by nursing personnel to patients who complained of difficulty initiating sleep or who requested a SHD. After 1 hour, if the patient still requested it, the nurse administered the SHD. MEASUREMENTS: The main outcomes of sleep quality and SHD use were measured by patient interview and chart abstraction. Feasibility and adherence to the protocol were tracked daily by patient and nurse interviews and chart abstraction. RESULTS: A cohort of 111 patients, mean age 79.3 (+/- 6.4), 68% women, received the sleep protocol. Patients required the protocol for a mean of 4.9 days per patient, totalling 539 patients-days. The overall adherence rate was 400/539 (74%) patient-days. The rate of complete nonadherence was 139/539 (26%), with reasons for nonadherence including nurse nonadherence in 30 (6%), patient refusal in 104 (19%), and medical contraindications in five (1%). The quality of sleep correlated strongly with the number of parts of the protocol received, suggesting a dose-response relationship, with the highest correlation for receiving two to three parts (p = .64, P < 0.001). The sleep protocol was successful in reducing SHD use from the baseline preintervention rate of 51/94 (54%) to 34/111 (31%) (P < .002). The sleep protocol had a stronger association with quality of sleep (p = .75, P = .001) than did SHDs (p = .07, P = .45). However, chronic SHD users were more likely to refuse the protocol than nonusers (64% vs 41%, P < .03) and received SHDs 4.5 times more often than nonusers (67% vs 15%, P = .001). CONCLUSION: The nonpharmacologic sleep protocol provides a feasible, effective, and nontoxic alternative to SHDs to promote sleep in older hospitalized patients. Use of the protocol can substantially decrease use of SHDs. 相似文献
913.
JA Bergfeld 《Canadian Metallurgical Quarterly》1998,80(12):1833-6; discussion 1846-50
914.
HJ Chen L Zhang J Cox JA Cunningham FL Chung 《Canadian Metallurgical Quarterly》1998,11(12):1474-1480
2,3-Epoxy-4-hydroxynonanal (EH) is a bifunctional aldehyde formed by epoxidation of trans-4-hydroxy-2-nonenal, a peroxidation product of omega-6 polyunsaturated fatty acids. EH is mutagenic and tumorigenic and capable of modifying DNA bases forming etheno adducts in vitro. Recent studies showed that etheno adducts are present in tissue DNA of humans and untreated rodents, suggesting a potential endogenous role of EH in their formation. A sensitive assay is needed so we can determine whether EH is involved in etheno adduct formation in vivo and study the biological significance of the etheno adducts in DNA. In this study, we developed a gas chromatography/negative ion chemical ionization/mass spectrometry assay for the analysis of 1, N6-ethenoadenine (epsilonAde) and 7-(1', 2'-dihydroxyheptyl)-3H-imidazo[2,1-i]purine (DHH-epsilonAde) in DNA; both are products from the reaction of adenine with EH. The assay entails the following sequence of steps: (1) addition of [15N5]epsilonAde and [15N5]DHH-epsilonAde to DNA as internal standards, (2) acid hydrolysis of DNA, (3) adduct enrichment by C18 solid phase extraction (SPE), (4) derivatization by pentafluorobenzylation (PFB), (5) separation of PFB-epsilonAde and PFB-DHH-epsilonAde on a Si SPE column, (6) acetonide (ACT) formation of PFB-DHH-epsilonAde, and (7) GC/MS analysis with selective ion monitoring (SIM). The limit of detection by on-column injection for PFB-epsilonAde monitoring of the (M - PFB)- ion at m/z 158 was 30 amol and for ACT-PFB-DHH-epsilonAde monitoring of the (M - PFB)- ion at m/z 328 was 0.4 fmol; the detection limits for the entire assay were 6.3 fmol for epsilonAde and 36 fmol for DHH-epsilonAde. In calf thymus DNA modified with EH at 37 degreesC for 50 h, both epsilonAde and DHH-epsilonAde were detected at high levels by this method, 4.5 +/- 0.7 and 90.8 +/- 8.7 adducts/10(3) adenine, respectively. These levels were also verified by HPLC fluorescence analysis, indicating that EH extensively reacts with adenine in DNA, forming etheno adducts. The high sensitivity of the assay suggests that it may be used in the analysis of ethenoadenine adducts in vivo. 相似文献
915.
916.
917.
918.
Ketoprofen is a chiral non-steroidal anti-inflammatory drug (NSAID) available as a racemic (rac) mixture of S-(+)- and R-(-)-isomers. Its inhibitory effect on prostaglandin biosynthesis resides virtually in the S-form. Interestingly, R-ketoprofen does not undergo substantial metabolic inversion in humans. Though contraindicated during the last trimester of pregnancy, NSAIDs, including ketoprofen, are used as tocolytic agents in some cases. The S/R plasma concentration ratio was reported to average 2.3 in premature neonates whose mothers were given rac-ketoprofen and to be close to 1 in the maternal plasma. Thus, we investigated the placental transfer of rac-ketoprofen in vitro using Schneider's perfused human cotyledon model. Glucosed Earle solutions with and without human serum albumin (HSA) were used. Several maternal perfusates were tested with different rac-ketoprofen concentrations together with 20 mg L-1 of antipyrine as a reference substance. Ketoprofen enantiomers were assayed by a specific HPLC method with derivatization procedure. HSA concentrations in maternal perfusate influenced the placental transfer of ketoprofen enantiomers. In the absence of HSA in the maternal perfusate, the S-(+)/R-(-) concentration ratio was close to 1 in the fetal perfusate. By contrast, this ratio averaged 1.44 after addition of HSA 10 g L-1 on the maternal side. Similar results were found for dialysis experiments using an inert Spectrapor 2 membrane suggesting that the S-(+)-free concentration is superior to the R-(-)-free concentration in the presence of HSA. Direct measurements of the free concentrations by centrifugal ultrafiltration confirmed this hypothesis. Accordingly, the data observed in vivo may result, at least in part, from the stereoselective protein binding of ketoprofen. 相似文献
919.
M Schuler C Rochlitz JA Horowitz J Schlegel AP Perruchoud F Kommoss CT Bolliger HU Kauczor P Dalquen MA Fritz S Swanson R Herrmann C Huber 《Canadian Metallurgical Quarterly》1998,9(14):2075-2082
Mutations of the tumor suppressor gene p53 are the most common genetic alterations observed in human cancer. Loss of wild-type p53 function impairs cell cycle arrest as well as repair mechanisms involved in response to DNA damage. Further, apoptotic pathways as induced by radio- or chemotherapy are also abrogated. Gene transfer of wild-type p53 was shown to reverse these deficiencies and to induce apoptosis in vitro and in preclinical in vivo tumor models. A phase I dose escalation study of a single intratumoral injection of a replication-defective adenoviral expression vector encoding wild-type p53 was carried out in patients with incurable non-small cell lung cancer. All patients enrolled had p53 protein overexpression as a marker of mutant p53 status in pretreatment tumor biopsies. Treatment was performed either by bronchoscopic intratumoral injection or by CT-guided percutaneous intratumoral injection of the vector solution. Fifteen patients were enrolled in two centers, and were treated at four different dose levels ranging from 10(7) to 10(10) PFU (7.5 x 10(9) to 7.5 x 10(12) particles). No clinically significant toxicity was observed. Successful transfer of wild-type p53 was achieved only with higher vector doses. Vector-specific wild-type p53 RNA sequences could be demonstrated in posttreatment biopsies of six patients. Transient local disease control by a single intratumoral injection of the vector solution was observed in four of those six successfully transduced patients. There was no evidence of clinical responses at untreated tumor sites. Wild-type p53 gene therapy by intratumoral injection of a replication-defective adenoviral expression vector is safe, feasible, and biologically effective in patients with advanced non-small cell lung cancer. 相似文献
920.
OBJECTIVES: This study examined how immunization-related beliefs, attitudes, and perceived control mediate up-to-date immunization among various sociodemographic groups. METHODS: Statewide estimates of immunization rates among children up to the age of 2 years were obtained via a multistage cluster sample. In-person interviews were conducted with 4832 parents. Information about immunization was obtained from official records or from health care providers. RESULTS: Differences in immunization among sociodemographic groups were mediated by beliefs about objective barriers to immunization, protection, medical contraindication, safety concerns, distrust, and natural immunity. Protection beliefs contributed to positive attitudes toward immunization; beliefs in natural immunity and safety concerns contributed to negative attitudes. Beliefs about objective barriers, distrust, safety concerns, and medical contraindications influenced perceived control over immunization. Positive attitudes and a strong sense of control contributed to higher immunization rates. CONCLUSION: These findings provide a basis for efficient educational campaigns by specifying which beliefs should be bolstered (because they facilitate proper immunization) and which should be targeted for change (because they hinder proper immunization) in various sociodemographic groups. 相似文献