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61.
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
62.
Exchange lists: revised 1986   总被引:2,自引:1,他引:1  
A committee composed of members of The American Dietetic Association and the American Diabetes Association has revised Exchange List for Meal Planning. Changes were made, as deemed necessary, on the basis of nutritional recommendations for persons with diabetes as understood in 1986. Major changes include rewriting the text to make it more useful in the education of persons with diabetes; changing the order of the exchange lists to emphasize a high-carbohydrate, high-fiber diet, as well as to better reflect the order of foods in menu planning; adding symbols to foods high in fiber and sodium; changing nutritive values for the starch/bread and fruit lists; adding lists of combination foods, free foods, and foods recommended only for occasional use; developing a data base; and initiating a plan for field testing and evaluation. The committee also developed a simplified meal planning tool, Healthy Food Choices, to be used for initial or "survival" level education. In poster format, foods are grouped by calories into six food groups. Approximate portion sizes of commonly used foods are listed. Blank lines are provided for the nutrition counselor to write in a suggested menu or meal plan for the client. Because the booklet does not use the word "diabetes" specifically, it is appropriate as a general teaching tool.  相似文献   
63.
目的:通过对骨髓单个核细胞在体外与不同细胞因子培养,了解不同细胞因子对骨髓淋巴细胞的激活能力和对骨髓干祖细胞的损伤情况。方法:将IL-1、IL-2、γ-IFN、CD3单抗进行不同组合后,在体外与骨髓单个核细胞分成对照组、IL-2组、CD3-AK、CIK组进行培养。培养过程中观察细胞形态和数量的变化,并在培养后检测免疫活性细胞的细胞毒性和造血干细胞的保存情况。结果:培养过程中对照组细胞数量减少;IL-2组细胞数量变化不明显;CD3-AK组、CIK组细胞数量显著增多,并出现较多的集聚成簇的淋巴样细胞,培养后其细胞毒性明显强于对照组及IL-2组,但细胞数量增加和细胞毒性无明性差异,培养后各组造血干细胞保存情况约16%~87%。结论:IL-2、CD3单抗在体外与骨髓单个核细胞培养后,即能激活免疫细胞增殖,又能保留足够的造血干细胞。  相似文献   
64.
65.
IntroductionHIV diagnosis is the necessary first step towards HIV care initiation, yet many persons living with HIV (PLWH) remain undiagnosed. Employing multiple HIV testing strategies in tandem could increase HIV detection and promote linkage to care. We aimed to assess an intervention to improve HIV detection within socio‐sexual networks of PLWH in two sexually transmitted infections (STI) clinics in Lilongwe, Malawi.MethodsWe conducted a randomized controlled trial to evaluate an intervention combining acute HIV infection (AHI) screening, contract partner notification and social contact referral versus the Malawian standard of care: serial rapid serological HIV tests and passive partner referral. Enrolment occurred between 2015 and 2019. HIV‐seropositive persons (two positive rapid tests) were randomized to the trial arms and HIV‐seronegative (one negative rapid test) and ‐serodiscordant (one positive test followed by a negative confirmatory test) persons were screened for AHI with HIV RNA testing. Those found to have AHI were offered enrolment into the intervention arm. Our primary outcome of interest was the number of new HIV diagnoses made per index participant within participants’ sexual and social networks. We also calculated total persons, sexual partners and PLWH (including those previously diagnosed) referred per index participant.ResultsA total of 1230 HIV‐seropositive persons were randomized to the control arm, and 561 to the intervention arm. Another 12,713 HIV‐seronegative or ‐serodiscordant persons underwent AHI screening, resulting in 136 AHI cases, of whom 94 enrolled into the intervention arm. The intervention increased the number of new HIV diagnoses made per index participant versus the control (ratio: 1.9; 95% confidence interval (CI): 1.2 to 3.1). The intervention also increased the numbers of persons (ratio: 2.5; 95% CI: 2.0 to 3.2), sexual partners (ratio: 1.7; 95% CI: 1.4 to 2.0) and PLWH (ratio: 2.3; 95% CI: 1.7 to 3.2) referred per index participant.ConclusionsCombining three distinct HIV testing and referral strategies increased the detection of previously undiagnosed HIV infections within the socio‐sexual networks of PLWH seeking STI care. Combination HIV detection strategies that leverage AHI screening and socio‐sexual contact networks offer a novel and efficacious approach to increasing HIV status awareness.  相似文献   
66.
目的 探讨人胰弹力蛋白酶Ⅰ (Humanpancreaticelastase 1 ,HPE1 )放射免疫测定 (Radioimmunoassay ,RIA)和核糖核酸酶(Ribonuclease ,RNase)活性检测的临床价值。方法 参照Satake等建立的改良HPE1RIA和Thomas等的改良酸溶性产物法检测 82例正常成年人和 2 2 2例各类患者血清并分析结果。结果  82例健康成人HPE1值为 2 3.8( 3.4ng L) ,RNase活性为 5 7.0 3( 1 2 .1 6 μ ml) ;急性胰腺炎和胰腺癌HPE1 值明显高于其他疾病 (P <0 .0 1 )。联合检测HPE1 、RNase活性可提高胰腺癌的检出率 ( 92 .47% )。结论 HPE1 RIA对急性胰腺炎有诊断价值 ,联合检测HPE1 、RNase活性检测对胰腺癌诊断有一定的临床价值  相似文献   
67.
The tetracycline analogs minocycline and doxycycline are inhibitors of metalloproteinases (MMPs) and have been shown to inhibit angiogenesis in vivo. To further study the mechanism of action of these compounds we tested them in an in vitro model of angiogenesis: aortic sprouting in fibrin gels. Angiogenesis was quantitated in this system by a unique application of planar morphometry. Both compounds were found to potently inhibit angiogenesis in this model. To further characterize the activity of these compounds against MMPs, we determined the IC50s of both compounds against representatives of three classes of metalloproteinases: fibroblast collagenase, stromelysin, and gelatinase A. Doxycycline was found to inhibit collagenase, gelatinase A and stromelysin with IC50s of 452 M, 56 M and 32 M, respectively. Minocycline was found to inhibit only stromelysin in the micromolar range with an IC50 of 290 M. Since these results suggest that these compounds may not have been inhibiting in vitro angiogenesis by an MMP-dependent mechanism, we decided to test the effects of the potent MMP inhibitor BB-94. This compound failed to inhibit aortic sprouting in fibrin gels, thus strongly suggesting that both doxycycline and minocycline act by an MMP-independent mechanism. These results have implications for the mechanism of action of tetracycline analogs, particularly where they are being considered for the treatment of disorders of extracellular matrix degradation including periodontal disease, arthritis, and tumor angiogenesis.  相似文献   
68.
OBJECTIVE: To use the Chambless criteria for empirically supported treatments and determine if any interventions for procedure-related pain in children and adolescents can be designated as "well established," "probably efficacious," or "promising." METHODS: The Chambless criteria were applied to 13 treatment outcome studies identified by a comprehensive literature review. RESULTS: A detailed summary is provided for each study, including the following information: citation, subjects, diagnostic criteria, baseline, experimental design, assessment measures, treatment protocol, outcome, and follow-up. CONCLUSIONS: Cognitive behavioral therapy is a "well-established treatment" for procedure-related pain in children and adolescents. Treatment includes breathing exercises and other forms of relaxation and distraction, imagery and other forms of cognitive coping skills, filmed modeling, reinforcement/incentive, behavioral rehearsal, and active coaching by a psychologist, parent, and/or medical staff member. I discuss future challenges for biobehavioral research and practice in the area of procedure-related pain.  相似文献   
69.
Powers A 《Women & health》1999,30(2):83-98
Newspaper coverage of the silicone breast implant controversy from 1992 through 1996 was analyzed to determine whether women in the United States were provided with a fair and balanced account. The paper also addressed whether or not Dow Corning's public relations campaign impacted newspaper coverage. All stories from the New York Times, the Chicago Tribune and the Wall Street Journal were analyzed. Findings suggested that early coverage of the controversy focused on the health risks of silicone breast implants while later coverage focused on the financial situations of the implant manufacturers. The most-interviewed sources were spokespersons for the implant manufacturers, while the least-interviewed sources were women with implants. The findings suggested that reporting patterns were influenced by the public relations efforts of the implant manufacturer, raising questions concerning the coverage of health care controversies involving large corporations seeking refuge from litigation.  相似文献   
70.
The authors review the relevant literature regarding home health care patient profiles. An empirical analysis is provided from archival data for a home infusion company servicing patients in urban and rural areas. The results are provided as a 2 x 2 matrix for patients in urban and rural areas seeing either a specialist or primary care physicians. A series of moderated regressions indicate that type of treating physician, patient's gender, geographic residence and level of acuity are cogent in predicting the complexity of prescribed infusion therapies. Managerial implications are provided for the home care marketer in segmenting patient markets for infusion services.  相似文献   
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