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排序方式: 共有137条查询结果,搜索用时 31 毫秒
51.
52.
Corrigan PW River LP Lundin RK Penn DL Uphoff-Wasowski K Campion J Mathisen J Gagnon C Bergman M Goldstein H Kubiak MA 《Schizophrenia bulletin》2001,27(2):187-195
The effects of three strategies for changing stigmatizing attitudes--education (which replaces myths about mental illness with accurate conceptions), contact (which challenges public attitudes about mental illness through direct interactions with persons who have these disorders), and protest (which seeks to suppress stigmatizing attitudes about mental illness)--were examined on attributions about schizophrenia and other severe mental illnesses. One hundred and fifty-two students at a community college were randomly assigned to one of the three strategies or a control condition. They completed a questionnaire about attributions toward six groups--depression, psychosis, cocaine addiction, mental retardation, cancer, and AIDS--prior to and after completing the assigned condition. As expected, results showed that education had no effect on attributions about physical disabilities but led to improved attributions in all four psychiatric groups. Contact produced positive changes that exceeded education effects in attributions about targeted psychiatric disabilities: depression and psychosis. Protest yielded no significant changes in attributions about any group. This study also examined the effects of these strategies on processing information about mental illness. 相似文献
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54.
Uptake of a superparamagnetic contrast agent imaged by MR with high spectral and spatial resolution.
G S Karczmar X Fan H A Al-Hallaq M Zamora J N River C Rinker-Schaeffer M Zaucha K Tarlo K Kellar 《Magnetic resonance in medicine》2000,43(5):633-639
Conventional MRI implicitly treats the proton signal as a single, narrow Lorentzian. However, water signals in vivo are often in homogeneously broadened and have multiple resolvable components. These components represent discrete populations of water molecules within each pixel which are affected differently by physiology and contrast agents. Accurate measurement of each component of the water resonance can improve anatomic and functional MR images and provide insight into the structure and dynamics of subpixelar microenvironments. This report describes high spectral and spatial resolution (HiSS) MR imaging of rodent prostate tumors before and after injection of a superparamagnetic contrast agent. HiSS datasets were used to synthesize images in which intensity is proportional to peak height, peak frequency, and linewidth. These images showed anatomic features which were not clearly delineated in conventional T(2) and gradient echo images. HiSS images obtained after injection of the contrast agent showed T *(2) and T(1) changes which were not seen in conventional images. These changes are associated with microvessel density and permeability. The results suggest HiSS with superparamagnetic contrast agents has the potential to improve characterization of tumors. 相似文献
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56.
Vadim Y U. Kuperman Jonathan N. River Martha Z. Lewis Leslie M. Lubich Gregory S. Karczmar 《Magnetic resonance in medicine》1995,33(3):318-325
Experiments were performed to determine whether changes in T2*-weighted MR images during and after hyperoxia differentiate tumors from normal tissue. Mammary adenocarcinomas implanted in the right hind limbs of rats were studied. Gradient echo images were obtained at 2 Tesla with an evolution time of 20 ms and a recycle time of 1 s. Breathing gas was either air or 100% O2. Significant increases in image intensity were observed in tumor centers and rims during hyperoxia while much smaller changes were detected in the surrounding muscle. The relaxation rate (1/T2*) in tumors decreased during hyperoxia by an average of 2.5 ± 1.0 s?1, while in muscle the average change was an increase of 0.6 ± 2.1 s?1. The largest decreases in relaxation rate were detected in non-necrotic tumor regions with relatively low density of blood vessels. Immediately following hyperoxia significant decreases in intensity were detected in tumors while much smaller decreases were detected in the surrounding muscle. 相似文献
57.
The effect of estrogen and progesterone on beta-adrenergic receptor activity in rabbit lung tissue 总被引:3,自引:0,他引:3
A H Moawad L P River S J Kilpatrick 《American journal of obstetrics and gynecology》1982,144(5):608-613
Study of the effect of sex steroids on the development of beta-adrenergic receptors may be essential to an understanding of the mechanisms of both lung maturation and the initiation of labor. (3H)Dihydroalprenolol (DHA) was used to quantify beta-adrenergic receptor sites in mature and immature rabbit lung tissue. DHA binding was rapid, saturable, of high affinity (dissociation constant = 2 nM), and of low capacity (246 to 576 fmoles/mg of protein), and a adrenergic competitors demonstrated both stereoselectivity ([-]isomer much greater than [+]isomer) and a rank order of potency (isoproterenol much greater than norepinephrine greater than epinephrine) characteristic of the beta-adrenergic receptor. beta-Adrenergic receptors in the lung tissue of both mature and immature female New Zealand White rabbits were investigated under various sex steroid situations. Estrogen (diethylstilbestrol, 5 micrograms/day for 10 days) increased the beta-adrenergic receptor site number in immature rabbits compared to matched controls (435 versus 339 fmoles/mg of protein, p less than 0.02 by paired t test). Addition of progesterone (diethylstilbestrol, 5 micrograms/day for 10 days, plus progesterone, 5 mg/day for 3 days) returned the beta-adrenergic receptor site number to control values (321 fmoles/mg of protein, p less than 0.01). In mature rabbits, treatment with progesterone alone (10 mg/day for 4 days) caused a significant reduction in beta-adrenergic receptor site numbers compared to untreated, matched controls (357 versus 493 fmoles/mg of protein, p less than 0.05 by paired t test). in the presence of estrogen, beta-adrenergic receptor activity is enhanced in both mature and immature rabbit lung tissue. Addition of progesterone restores this activity to control values. 相似文献
58.
Malignant skin tumors in multiple myeloma 总被引:1,自引:0,他引:1
59.
Ho PL Wong RC Yip KS Loke SL Leung MS Mak GC Chow FK Tsang KW Que TL;COMBAT study group 《Diagnostic microbiology and infectious disease》2007,59(4):439-445
This study evaluated the antimicrobial resistance profile of outpatient urinary Escherichia coli isolated from women obtained throughout Hong Kong during 2004-2005. Of 1067 single patient isolates analyzed, 60.1% were resistant to ampicillin, 34% were resistant to co-trimoxazole, and 22.1% were resistant to ciprofloxacin. Thirty-four (6.6%) of 519 isolates in 2004 and 55 (10%) of 548 isolates in 2005 were extended-spectrum beta-lactamase (ESBL) producers with a CTX-M phenotype. Rates of non-beta-lactam resistance and ESBL production were strongly influenced by patient age. The age-stratified rates for dual co-trimoxazole and ciprofloxacin resistance and for ESBL production were 10.9% and 7.6% in women aged 18-35 years, 13% and 6.9% in women aged 36-50 years, 20.4% and 8.8% in women aged 51-64 years, and 23.7% and 11.8% in women aged > or =65 years, respectively. Nitrofurantoin and fosfomycin remain active against >90% of the isolates, irrespective of the resistance phenotypes for other drugs. Our results documented the emergence of problematic resistance phenotypes among community urinary E. coli and highlight the need to explore strategies for their containment. 相似文献
60.
Community emergence of CTX-M type extended-spectrum beta-lactamases among urinary Escherichia coli from women 总被引:1,自引:0,他引:1
Ho PL Poon WW Loke SL Leung MS Chow KH Wong RC Yip KS Lai EL Tsang KW;COMBAT study group 《The Journal of antimicrobial chemotherapy》2007,60(1):140-144
OBJECTIVES: To conduct a territory-wide study of extended-spectrum beta-lactamases (ESBLs) among community isolates of urinary Escherichia coli from women in Hong Kong. METHODS: Up to 50 consecutive single-patient E. coli isolates, collected from 13 laboratories in 2004, were studied. The ESBLs were characterized by PCR sequencing using specific primers. The epidemiological relationship of the isolates was studied by PFGE and phylogenetic group PCRs. RESULTS: Forty-two ESBL producers were found among 600 consecutive isolates tested. The ESBL prevalence was 7.3% (15/205) for women aged 18-35 years, 5% (11/219) for women aged 36-50 years, 6.3% (4/63) for women aged 51-64 years and 10.6% (12/113) for women aged >or=65 years (P=0.3). The ESBL-producing isolates were often multidrug-resistant and CTX-M-14 was found in 37 isolates, CTX-M-15 in 3 isolates and CTX-M-3 in 2 isolates. PFGE revealed no significant clusters among the ESBL producers. Overall, CTX-M-14 producers were significantly more likely to belong to group D than non-ESBL producers [18/37 (48.6%) versus 13/57 (22.8%), P=0.009]. However, 7 of 13 (53.8%) CTX-M-14 producers from women aged 18-35 years represented phylogenetic group B2, compared with 7 of 24 (29.2%) for women of all other ages (P=0.1). CONCLUSIONS: The study documented the community emergence of CTX-M as the predominant ESBL type among urinary isolates from women. The spread of CTX-M enzymes among isolates from young women is concerning and deserves close monitoring. 相似文献