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61.
苯氧烷胺类化合物的合成及其抗高血压活性   总被引:1,自引:0,他引:1  
前以2,6-二甲基苯氧乙叉为母体合成了一系列化合物,其中1-(2,6-二甲基苯氧基-2-(3,4-二甲氧基苯乙胺)-丙烷盐酸盐(Ⅰ)有较强而特久的降压作用。进一步研究又表明它具有阻断α-肾上腺素受体并兼有钙拮抗作用。  相似文献   
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The individual infant's neurodevelopmental process provides an integrative framework for the delivery of medical care needed to assure the infant's survival and quality of outcome. The infant's neurobehavioral functioning and expression provides an opportunity for caregivers to estimate the individual infant's current strengths, vulnerabilities and threshold to disorganization, as well as to identify the infant's strategies in collaborating in his or her best progression. This perspective supports caregivers in seeing themselves in a relationship with the infant, and in considering opportunities to enhance the infant's strengths and reduce apparent stressors in collaboration with the infant and the family. The results of several randomized studies supporting the effectiveness of such a neuro developmental approach to NICU care will be presented, and suggest implications for staff education and nursery-wide implementation.  相似文献   
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Comparison of real-time cholecystosonography and oral cholecystography   总被引:1,自引:0,他引:1  
Krook  PM; Allen  FH; Bush  WH  Jr; Malmer  G; MacLean  MD 《Radiology》1980,135(1):145
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Burbank  FH; Enzmann  D; Keyes  GS; Brody  WR 《Radiology》1984,152(3):725-729
A hybrid digital subtraction angiography technique and noise-reduction algorithm were used to evaluate the carotid bifurcation. Temporal, hybrid, and reduced-noise hybrid images were obtained in right and left anterior oblique projections, and both single- and multiple-frame images were created with each method. The resulting images were graded on a scale of 1 to 5 by three experienced neuroradiologists. Temporal images were preferred over hybrid images (average score = 3.2 and 2.4, respectively). The percentage of nondiagnostic examinations, as agreed upon by two readers, was higher for temporal alone than temporal + hybrid (4 and 1, respectively). In addition, also by agreement between two readers, temporal + hybrid images significantly increased the number of bifurcations seen in two views (87%) compared to temporal subtraction alone (64%).  相似文献   
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It has been recommended that women aged 40-49 years with a significant family history of breast cancer should be offered annual mammography screening (http://www.nice.org.uk). An observational study known as FH01 (http://www.screeningservices.org/btw/fh01/index.asp) is evaluating this policy in a cohort of 6000 women at moderately increased risk of breast cancer due to family history. The main aims are to assess the likely impact on breast cancer mortality and cost-effectiveness. Measuring these outcomes is challenging in an environment where a randomized trial is not feasible and there is no natural comparison group. In this paper, we present some approaches to estimating effectiveness and the planned analyses. These involve comparison of disease stage and likely consequent breast cancer mortality in the cohort offered screening with that estimated in the absence of screening. The estimation uses observed outcomes in external populations and estimated outcomes for the hypothetical situation where screening had not taken place.  相似文献   
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In previous clinical studies, excellent visualization of tumor lesions has been observed with 131I-labeled monoclonal antibody (mAb) G250 in patients with renal cell carcinoma (RCC). In several cases, 131I-cG250 immunoscintigraphy disclosed tumor lesions that were not visualized by radiography or CT. To improve image quality, we aimed to develop a 99mTc-labeled mAb G250 preparation for radioimmunodetection of RCC. We studied in vitro stability, biodistribution and imaging potential of three 99mTc-labeled G250 preparations in nude mice with subcutaneous RCC xenografts.125I-G250 and the nonspecific mAb 131I-MN14 were used as control antibodies. METHODS: The mAb G250 was labeled with 99mTc according to three methods using: (a) S-hydrazinonicotinamide (HYNIC), (b) S-benzoylmercaptoacetyltriglycine (MAG3) and (c) a direct labeling method (Schwarz method). The stability of all preparations was tested in serum at 37 degrees C during 48 h. In addition, diethylenetriamine pentaacetic acid, cysteine and glutathione challenge assays were performed. RESULTS: All preparations showed good stability in serum during the 48-h incubation period. 99mTc-G250 (Schwarz) showed release of the radiolabel at a 100-fold or higher molar excess of cysteine and at a 10,000-fold or higher molar excess of glutathione. 99mTc-MAG3-G250 showed release of the radiolabel at a 10,000-fold molar excess of cysteine. 99mTc-HYNIC-G250 was stable under all conditions. Tumors were clearly visualized with all preparations. 99mTc-G250 (Schwarz) showed significantly lower blood levels (3.8 %ID/g) compared with all other preparations (11.2, 13.4 and 13.4 %ID/g for 99mTc-HYNIC-G250, 99mTc-MAG3-G250 and 125I-G250, respectively, 48 h postinjection). At 48-h postinjection, mean tumor uptake was very high with all mAb G250 preparations: 92.4 (99mTc-HYNIC-G250), 125.9 (99mTc-MAG3-G250), 29.4 (99mTc-G250 Schwarz) and 75.4 (125I-G250) %ID/g. Mean tumor uptake of the nonspecific 131I-MN14 mAb was 6.6 %ID/g. CONCLUSION: In this study, 99mTc-HYNIC-G250 showed excellent in vitro stability and tumor targeting. Moreover, this preparation could be labeled with high efficiency (>95%) at room temperature within 15 min. Therefore, 99mTc-HYNIC-G250 seems to be an ideal candidate for radioimmunodetection of RCC.  相似文献   
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