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排序方式: 共有639条查询结果,搜索用时 15 毫秒
61.
Maxime Lafond Nuria G. Salido Kevin J. Haworth Alexander S. Hannah Gregory P. Macke Curtis Genstler Christy K. Holland 《Ultrasound in medicine & biology》2021,47(3):693-709
The EkoSonic endovascular system has been cleared by the U.S. Food and Drug Administration for the controlled and selective infusion of physician specified fluids, including thrombolytics, into the peripheral vasculature and the pulmonary arteries. The objective of this study was to explore whether this catheter technology could sustain cavitation nucleated by infused Definity, to support subsequent studies of ultrasound-mediated drug delivery to diseased arteries. The concentration and attenuation spectroscopy of Definity were assayed before and after infusion at 0.3, 2.0 and 4.0 mL/min through the EkoSonic catheter. PCI was used to map and quantify stable and inertial cavitation as a function of Definity concentration in a flow phantom mimicking the porcine femoral artery. The 2.0 mL/min infusion rate yielded the highest surviving Definity concentration and acoustic attenuation. Cavitation was sustained throughout each 15 ms ultrasound pulse, as well as throughout the 3 min infusion. These results demonstrate a potential pathway to use cavitation nucleation to promote drug delivery with the EkoSonic endovascular system. 相似文献
62.
Background
Variance of peak bone mass has a substantial genetic component, as has been shown with twin studies examining quantitative measures such as bone mineral density (BMD) and quantitative ultrasound (QUS). Evidence implicating single nucleotide polymorphisms (SNPs) of the transforming growth factor beta-1 (TGFB1) gene is steadily accumulating. However, a comprehensive look at multiple SNPs at this locus for their association with indices of peak bone mass has not been reported. 相似文献63.
Villa O Del Campo M Salido M Gener B Astier L Del Valle J Gallastegui F Pérez-Jurado LA Solé F 《American journal of medical genetics. Part A》2007,(10):1108-1113
We report on a child with a small supernumerary marker chromosome (sSMC) causing partial trisomy 6p. The child showed a phenotype consisting of neonatal craniosynostosis, microcephaly, and borderline developmental delay. By molecular techniques the sSMC has been shown to contain approximately 16 Mb of genomic DNA from 6p21.1 to 6cen, being de novo and of maternal origin. 相似文献
64.
65.
The spectrum of clinical and pathological manifestations of AIDS in a consecutive series of autopsied patients in Mexico. 总被引:1,自引:0,他引:1
A Mohar J Romo F Salido J Jessurun S Ponce de León E Reyes P Volkow O Larraza M A Peredo C Cano 《AIDS (London, England)》1992,6(5):467-473
OBJECTIVE: Little is known about the clinical profile of AIDS in Latin American populations. This study characterizes the clinical and pathological manifestations of AIDS in a representative series of Mexican AIDS patients at autopsy. DESIGN: The clinical and pathological findings were abstracted retrospectively for a sequential series of autopsied AIDS patients. SETTING: Autopsies were conducted at the four major tertiary level hospitals that serve the majority of AIDS patients in Mexico City. PATIENTS: Subjects included 177 consecutive patients diagnosed with AIDS between March 1984 and January 1989 who subsequently died and were autopsied in the same period in the study hospitals. MAIN OUTCOME MEASURES: Demographic characteristics, including age, gender, residence, socioeconomic status, and risk group; clinical presentation and autopsy findings, including opportunistic infections and malignancies. RESULTS: Sixty per cent of the AIDS patients presented with wasting syndrome. The most common infections were cytomegalovirus (69%), tuberculosis (25%), and Pneumocystis carinii pneumonia (24%). Central nervous system infections were also common and included toxoplasmosis (19%) and cryptococcoses (10%). Kaposi's sarcoma was present in 30% of cases and non-Hodgkin's lymphoma in 9%. CONCLUSION: Clinical manifestation, and types and frequency of opportunistic infections in our Mexican AIDS patients were more similar to those seen in AIDS patients in Africa and Haiti than in the United States and Europe. These findings suggest that the AIDS epidemic in Mexico has an 'intermediate' pattern and may be a prototype for Latin American countries. 相似文献
66.
Cytogenetic studies of 68 patients who developed secondary leukemia (SL)/dysmyelopoietic syndrome (DMS) after extensive chemotherapy and/or radiation therapy as well as patients who developed SL/DMS without such treatment showed that those patients who received radiation alone or with chemotherapy had more extensive numerical and structural abnormalities than those who received only chemotherapy. In terms of the specific chromosomal abnormalities, there are no differences between the various treatment groups. Hypodiploidy is the most common form of aneuploidy in these patients, with the most common numerical abnormality being the loss of chromosome 7. The most common structural abnormalities involved chromosomes 3 and 5. When compared with patients with de novo leukemia and DMS, the chromosomal abnormalities in these patients are more complex and extensive. Serial studies revealed that cytogenetic abnormalities do not precede the development of hematologic changes by significant time periods. 相似文献
67.
Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable. 相似文献
68.
S. Berrendero M. P. Salido A. Valverde A. Ferreiroa G. Pradíes 《Clinical oral investigations》2016,20(9):2403-2410
Objectives
To compare the fit of all-ceramic crowns fabricated from conventional silicone impressions with the fit of all-ceramic crowns fabricated from intraoral digital impressions.Methods
Thirty patients with 30 posterior teeth with a prosthetic demand were selected. Zirconia-based ceramic crowns were made using an intraoral digital impression system (Ultrafast Optical Sectioning technology) (digital group, D) and 2-step silicone impression technique (conventional group, C).To replicate the interface between the crown and the preparation, each crown was cemented on its corresponding clinical preparation using ultra-flow silicone. Each crown was embedded in resin to stabilize the registered interface. Specimens were sectioned in buccolingual orientation, and internal misfit was measured at different areas using stereomicroscopy (×40).Data was analysed using Student’s t test and Mann-Whitney test (α = 0.05).Results
No statistically significant differences were found (P > 0.05) between two groups. The mean internal misfit and mean marginal misfit were 170.9 μm (SD = 119.4)/106.6 μm (SD = 69.6) for group D and 185.4 μm (SD = 112.1)/119.9 μm (SD = 59.9) for group C.Conclusion
Ceramic crowns fabricated using an intraoral scanner are comparable to elastomer conventional impressions in terms of their marginal and internal fits. The mean marginal fit in both groups was within the limits of clinical acceptability.Clinical significance
Impressions based on Ultrafast Optical Sectioning technology can be used for manufacturing ceramic crowns in a normal workflow, with the same results as silicone conventional impressions.69.
A microculture assay for murine granulocyte-macrophage colony- stimulating factor (GM-CSF) has been developed using fetal liver GM colony-forming cells (CFC) isolated by fluorescence-activated cell sorting. These GM-CFC are free of mature hemopoietic cells, such as granulocytes and macrophages, which may interfere with direct assays for GM-CSF. The assay procedure allows the quantitation of GM-CSF within 48 hr by measuring the number of cells produced from 50 GM-CFC in microcultures (15 microliter). The assay is particularly simple to set up and score and yet, because of the reduced volumes, this assay is still capable of detecting 0.2 pg (i.e., 0.2 U) of GM-CSF within 48 hr, i.e., 100 times less GM-CSF than the conventional soft agar assay. By allowing the microcultures to develop for 7 days, the extra proliferation allows a further tenfold increase in the sensitivity of CSF detection. The time and cost of setting up hundreds of GM-CSF assays for fractions from chromatographic columns, e.g., reverse phase high performance liquid chromatography, is reduced by at least five- fold. Enough GM-CFC can be isolated and stored frozen in one afternoon to provide sufficient cells for the daily assay of 200 samples of GM- CSF for several months. Microassay results for several sources of GM- CSF at different stages of purification are compared to the results obtained from the soft agar assay. 相似文献
70.
O Falusi AL French EC Seaberg PC Tien DH Watts H Minkoff E Piessens A Kovacs K Anastos MH Cohen 《Clinical infectious diseases》2002,35(11):1414-1417
We assessed the prevalence and predictors of latent Toxoplasma infection in a large group of human immunodeficiency virus (HIV)-infected and HIV-uninfected at-risk US women. The prevalence of latent Toxoplasma infection was 15% (380 of 2525 persons) and did not differ by HIV infection status. HIV-infected women aged > or =50 years and those born outside of the United States were more likely to have latent Toxoplasma infection, with prevalences of 32% and 41%, respectively. 相似文献