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排序方式: 共有809条查询结果,搜索用时 31 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
Maxillary first molar with six canals 总被引:3,自引:0,他引:3
4.
K Tardiff P M Marzuk A C Leon C S Hirsch M Stajic L Portera N Hartwell 《Public health reports (Washington, D.C. : 1974)》1995,110(1):13-17
Although prior research has found that homes containing firearms and illicit drug and ethanol users are more likely to be the scene of a homicide than homes that do not contain these elements, the authors studied homicides on the streets as well as in homes so as to assess the role of firearms, cocaine, and ethanol in both settings. Using the files of the Chief Medical Examiner, the authors reviewed all 4,468 homicides occurring in New York City in 1990 and 1991. The most frequent places of occurrence were the streets and other outdoor places (49.6 percent) and the victims'' homes (19.3 percent). Firearms were the cause of death for 49.6 percent of homicides in the home and 80.3 percent of those on the streets. Use of cocaine and ethanol was found more frequently among victims killed on the streets than those killed at home. In addition, victims killed on the streets were more likely to be male, ages 15-24 years, and African American. Further research in regard to prevention and intervention strategies is needed, keeping in mind the different patterns of homicide on the streets compared with those occurring in other settings. 相似文献
5.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
6.
Jerrold S. Levine Barbara J. Pugh Daqing Hartwell John M. Fitzpatrick Ann Marshak-Rothstein David I. Beller 《European journal of immunology》1993,23(11):2951-2958
Macrophages (M?) from pre-diseased autoimmune-prone MRL mice (both MRL/+ and MRL/1pr) dramatically underproduce the cytokine interleukin-1 (IL-1) in comparison to M? from a number of normal strains. In this study we show that IL-1 dysregulation by MRL M? is fully expressed at birth, and that this defect does not change with time or the development of disease. We also constructed adult irradiation chimeras (consisting of A/J → MRL and MRL → A/J mice), and show that M? isolated from these chimeras display a pattern of IL-1 production indistinguishable from that of the donor strain controls. Moreover, when we constructed a mixed chimera (A/J + MRL → A/J), the A/J and MRL M? coexisting within the same animal retained their individual patterns of IL-1 production when isolated by negative selection. Taken together, these results provide the first substantive evidence for an intrinsic defect (IL-1 dysregulation) in M? from MRL autoimmune-prone mice. 相似文献
7.
M. M. Engelgau K. M. Narayan L. S. Geiss T. J. Thompson G. L. Beckles L. Lopez T. Hartwell W. Visscher L. Liburd 《Journal of the National Medical Association》1998,90(10):605-613
Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) is the first comprehensive community diabetes demonstration project in the United States in an African-American community. This article describes its intervention components and evaluation design. The development and implementation of Project DIRECT has included the community since the project''s beginning. Interventions are targeted in three areas: health promotion (improving diet and physical activity levels), outreach (improving diabetes awareness, detection of undiagnosed diabetes, and ensuring that persons with diabetes who are not receiving continuing diabetes care are integrated into the health-care system), and diabetes care (improving self-care, increasing access, and improving the quality of diabetes preventive care received within the health-care system). Evaluation will be internal (conducted by Project DIRECT staff to assess process outcomes in persons directly exposed to each specific intervention) and external (review of outcomes to assess the impact of the multi-intervention program at the level of the entire community). Because diabetes exacts a disproportionate toll among African Americans, the findings from this project should aid in developing strategies to lessen the burden of this disorder, particularly among minority populations. 相似文献
8.
9.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
10.
Smoking cessation factors among African Americans and whites. COMMIT Research Group. 总被引:7,自引:4,他引:3 下载免费PDF全文
J M Royce N Hymowitz K Corbett T D Hartwell M A Orlandi 《American journal of public health》1993,83(2):220-226
OBJECTIVES. This study was undertaken to explore smoking patterns and attitudes that influence smoking cessation and relapse among African Americans. METHODS. Baseline data from eight Community Intervention Trial for Smoking Cessation (COMMIT) sites were analyzed. RESULTS. Compared with Whites, African Americans who smoke less than 25 cigarettes per day were 1.6 times more likely to smoke within 10 minutes of awakening (a behavioral indicator of nicotine dependence), adjusting for education, age, and gender (OR = 1.2 for heavier smokers). African Americans reported a stronger desire to quit smoking and reported serious quit attempts in the past year. African Americans favored tobacco restrictions (they were 1.8 times more likely than Whites to view smoking as a serious community problem, 1.7 times more likely to favor restrictions on cigarette vending machines, and 2.1 times more likely to prohibit smoking in their car). African Americans were lighter/moderate, menthol smokers. CONCLUSIONS. African Americans find smoking socially unacceptable and are strongly motivated to quit, but their "wake-up" smoking may indicate high nicotine dependence, making abstinence difficult even for lighter smokers. 相似文献