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61.
62.
We analyzed the outcome results of 583 postdate pregnancies managed prospectively by one of three antepartum testing schemes, each predicated on the nonstress test. In scheme 1, we relied upon the contraction stress test for evaluation of the nonreactive nonstress test. In scheme 2, we used a modified biophysical profile to evaluate the nonreactive nonstress test. In addition, patients were tested semiweekly. In scheme 3, we added routine weekly ultrasound evaluation of amniotic fluid volume to scheme 2. Only in scheme 3 did we induce labor for decreased amniotic fluid volume or fetal cardiac decelerations irrespective of reactivity. The incidence of fetal distress, perinatal mortality, and perinatal morbidity was increased in babies with decelerations or decreased amniotic fluid volume. Nevertheless, outcome results in scheme 2 were improved over those with scheme 1 and were best with scheme 3. These results suggest a benefit to both semiweekly testing and liberalized criteria for intervention in postdate pregnancies. We also compared the outcome results of scheme 3 with those reported for schemes in which the weekly contraction stress test was used as the primary form of surveillance. We found the outcome results comparable in that both schemes showed minimal mortality and morbidity statistics but high intervention rates (25% to 30%). Differences in methodology and test criteria, however, make such comparisons less than ideal.  相似文献   
63.
The modification of a SiOCH based low-k by oxygen plasma in a transformer coupled plasma (TCP) is reported. Modification of the film is studied as function of TCP power and time. Spectroscopic ellipsometry (SE) and Fourier transformed infrared absorption spectroscopy (FTIR) measurements are used for characterization. Both techniques show that the modification (damage) depth increases with increasing TCP power. Optical emission spectroscopy (OES) indicates that adding TCP power increases the O/O2+ ratio in the plasma. By means of FTIR and OES, evidence is found for the removal of hydrogen and carbon from the low-k during plasma exposure. Using a two-layer SE fitting model, and no TCP power a refractive index (RI) of 1.44 for the chemically altered top layer was found. This RI decreases with TCP power. Presumably, at increased TCP power, relatively more radicals are generated and they penetrate more easily because of a less dense top layer.  相似文献   
64.
We show how a semiclassical representation of the atomic field may describe the interacting base gas at finite temperatures.  相似文献   
65.
This paper presents results of detailed studies of composite slag binders with mineral silica additions differing in reactivity. We have identified general trends and assessed the effects of composition, particle size, and binder hardening conditions on the normal consistency, paste setting time, hardening kinetics, strength, average density, and water absorption in composite slag binder stone. Using X-ray diffraction and scanning electron microscopy, we have identified the key features of structure formation in stone with mineral silica additions and examined the influence of additives on the composition and volume of the hardening products of composite slag binders. The results have been used to construct a model of the structure and structural elements of composite slag binder stone with mineral silica additions.  相似文献   
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67.
We have previously demonstrated that diphtheria toxin (DT) fused to human GM-CSF effectively eliminates human long-term leukemia initiating cells in SCID mice. However, because huGM-CSF does not react with the murine GM-CSF receptor possible side-effects to nonleukemic tissues could not be analyzed in the AML/SCID model. To overcome this problem, we used murine GM-CSF fused to DT and studied the therapeutic index in the rat leukemia model BNML/LT12. In DT-mGM-CSF dose escalation experiments, severe dose-dependent toxicity to organs such as liver, kidney and lung was observed. Therefore, the antileukemic effects were evaluated with the lower doses. Daily intraperitoneal bolus injections of 75 microg/kg/day for 7 days induced a 3 log leukemic cell kill. The dose of 75 microg/kg/day had no effect on the hemopoietic progenitor cell subsets. These in vivo studies show that the DT-GM-CSF fusion protein can be used for specifically targeting leukemic cells and thus has potential as a therapeutic agent in the treatment of AML.  相似文献   
68.
Evidence for clinically significant radiosensitization by the halogenated pyrimidine 5-iododeoxyuridine (IdUrd) continues to accumulate. In vitro radiosensitization has been demonstrated in human colon tumor cell lines following exposure to 1-10 micrometer. Coadministration of leucovorin (LV) increases radiosensitization, which correlates directly with increased IdUrd DNA incorporation. Clinical data regarding proliferation rates and thymidine kinase levels in tumors versus normal tissues suggest selective incorporation of IdUrd into gastrointestinal tumors may occur. The objectives of this Phase I study were: (a) to assess the feasibility of LV modulation of IdUrd radiosensitization by determining the maximum tolerated dose (MTD) of IdUrd plus LV; and (b) to perform correlative laboratory studies to investigate the potential of IdUrd plus LV to increase radiosensitization in vivo. Seventeen patients with unresectable or recurrent gastrointestinal adenocarcinomas received a 14-day course of continuous i.v. infusion of IdUrd prior to initiation of radiotherapy. Two additional 14-day infusions of IdUrd with LV were given during the course of radiotherapy (60 Gy in 6 weeks). The initial dose of IdUrd was 250 mg/m2/day and was escalated in subsequent patients to 400 and 600 mg/m2/day. The LV dose remained fixed at 250 mg/m2/day. Leukopenia was the dose-limiting toxicity, and 400 mg/m2/day was the MTD for this trial. At the MTD, the mean +/- SD steady-state plasma concentration of IdUrd during the infusion, measured by high-performance liquid chromatography, was 0.66 +/- 0.23 micrometer. There was no significant influence of LV on IdUrd DNA incorporation in peripheral blood granulocytes as measured by high-performance liquid chromatography. Based on toxicity data and correlative laboratory studies, a meaningful increase in radiosensitization would not be achieved with the IdUrd infusion schedule and dose of LV investigated compared with IdUrd alone.  相似文献   
69.
OBJECTIVES: To determine whether a two hour training programme for general practice reception staff could improve uptake in patients who had failed to attend for breast screening, and whether women from different ethnic groups benefited equally. DESIGN: Controlled trial, randomised by general practice. SETTING: Inner London borough of Newham. SUBJECTS: 2064 women aged 50-64 years who had failed to attend for breast screening. Women came from 26 of 37 eligible practices, 31% were white, 17% were Indian, 10% Pakistani, 14% black, 6% Bangladeshi, 1% Chinese, 4% were from other ethnic groups, and in 16% the ethnic group was not reported. MAIN OUTCOME MEASURES: Attendance for breast screening in relation to ethnic group in women who had not taken up their original invitation. RESULTS: Attendance in the intervention group was significantly better than in the control group (9% v 4%). The response was best in Indian women--it was 19% in the intervention group and 5% in the control group. CONCLUSIONS: This simple, low cost intervention improved breast screening rates modestly. Improvement was greatest in Indian women--probably because many practice staff shared their cultural and linguistic background. This intervention could be effective as part of a multifaceted strategy to improve uptake in areas with low rates.  相似文献   
70.
Cell growth and viability are dependent on the function of the multicatalytic proteinase complex (proteasome), a multisubunit particle that affects progression through the mitotic cycle by degradation of cyclins. Exposure of rodent fibroblasts and human lymphoblasts in culture to benzyloxycarbonyl-leucyl-leucyl-phenylalaninal (Z-LLF-CHO), a cell-permeable peptidyl aldehyde inhibitor of the chymotrypsin-like activity of the proteasome, resulted in the induction of apoptosis in a rapid, dose-dependent fashion. Fibroblasts transformed with ras and myc, lymphoblasts transformed by c-myc alone, and a Burkitt's lymphoma (BL) cell line that overexpresses c-Myc were up to 40-fold more susceptible to apoptosis than were either primary rodent fibroblasts or immortalized nontransformed human lymphoblasts, respectively. To determine whether such preferential apoptosis could impact upon tumor growth in vivo, toxicological studies were performed in mice with severe combined immunodeficiency and showed that mice tolerated single interscapular doses of Z-LLF-CHO without unacceptable toxicity. Severe combined immunodeficient mice bearing s.c. BL tumors in the flank were treated interscapularly with Z-LLF-CHO or a comparable dose of the peptidyl alcohol (Z-LLF-OH), which does not induce proteasome inhibition or apoptosis. Single doses of Z-LLF-CHO induced statistically significant (P < 0.0001) early tumor regression and a significant (P < 0.0001) delay in tumor progression. Analysis of tumor specimens revealed increased apoptosis in BL tumors from mice treated with Z-LLF-CHO. These results, showing a 42% tumor growth delay, indicate that proteasome inhibitors have the potential of curbing the growth of a c-myc-related tumor.  相似文献   
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