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81.
Higher plants have afforded a plethora of structurally varied biologically active secondary metabolite organic molecules, and accordingly have been subjected to wide experimental scrutiny in countries all over the world. In this short review the promise of just one phytochemical group, the flavonoids, will be focused upon. Compounds of this type which have been recently isolated and characterized in this laboratory, with potential use as cancer chemopreventives, cancer chemotherapeutic agents, and sucrose substitutes, will be described.  相似文献   
82.
ABSTRACT: BACKGROUND: Study-based HIV prevention interventions, especially those that are conducted on an international or multi-site basis, frequently require site-specific adaptations in order to (1) respond to socio-cultural differences in risk determinants, (2) to make interventions more relevant to target population needs, and (3) in recognition of 'public health diplomacy' issues. We report on the adaptations development, approval and implementation process and describe adaptations from the Project Accept voluntary counseling and testing, community mobilization and post-test support services intervention. METHODS: We reviewed all relevant documentation collected during the study intervention period (e.g. monthly progress reports; bi-annual steering committee presentations) and conducted a series of semi-structured interviews with project directors and between 12 and 23 field staff at each study site in South Africa, Zimbabwe, Thailand and Tanzania during 2009. Respondents were asked to describe (1) the adaptations development and approval process and (2) the most successful site-specific adaptations in terms of facilitating intervention implementation. RESULTS: Across sites, proposed adaptations were identified by field staff and submitted to project directors for review, on a formally planned basis. The cross-site intervention sub-committee then ensured fidelity to the study protocol before approving. Successfully-implemented adaptations included: intervention delivery adaptations (e.g. development of tailored counseling messages for immigrant labour groups in South Africa); environmental and infrastructural adaptations (e.g. use of local community centers as VCT venues in Zimbabwe); religious adaptations (e.g. dividing clients by gender in Muslim areas of Tanzania); economic adaptations (e.g. co-provision of income generating skills classes in Zimbabwe); epidemiological adaptations (e.g. provision of 'youth-friendly' services in South Africa, Zimbabwe and Tanzania), and social adaptations (e.g. modification of terminology to local dialects in Thailand; adjustment of service delivery schedules to suit seasonal and daily work schedules across sites). CONCLUSIONS: Adaptation selection, development and approval during multi-site HIV intervention research studies should be a planned process that maintains fidelity to the study protocol. The successful implementation of appropriate site-specific adaptations may have important implications for intervention implementation, from both a service uptake and a 'public health diplomacy' perspective.  相似文献   
83.
目的:测定炎痛净乳膏中双氯芬酸钠和苯佐卡因的含量。方法:高效液想象以谱法,甲醇为提取溶剂,地西泮为内标,No-va-PakC18色谱柱,甲醇-水-冰醋酸(80:20:0.5)为流动相,检测波长为283nm。结果:双氯芬酸钠和苯佐卡因在5μg/ml-40μg/ml范围内,其浓度与峰面积均呈良好的线性关系(r=0.9999),平均回收率分别为101.0%,RSD=1.21%,99.8%,RSD=0.62%。结论:本法专属性强,操作简便,结果准确。  相似文献   
84.
85.
Glazer  HS; Gutierrez  FR; Levitt  RG; Lee  JK; Murphy  WA 《Radiology》1985,157(1):149-155
Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients.  相似文献   
86.
Psoas muscle disorders: MR imaging   总被引:3,自引:0,他引:3  
Lee  JK; Glazer  HS 《Radiology》1986,160(3):683-687
Nineteen patients with evidence of psoas and iliopsoas abnormalities on computed tomographic (CT) scans (12 with metastases, three with lymphoma, two with hematoma, and two with abscess) were examined with magnetic resonance (MR) imaging. The abnormal psoas could be identified on both T1- and T2-weighted spin-echo images, although T2-weighted sequences provided better contrast. The psoas muscle can be affected by one of three mechanisms: total replacement, lateral displacement, or medial displacement. In four patients in whom the CT study showed apparent enlargement of a psoas muscle, subsequent MR imaging examinations demonstrated that the psoas muscle was compressed and displaced laterally by a paraspinal mass. MR images provided better contrast between the normal and abnormal psoas than CT scans in nine cases; MR images were inferior to CT scans in two cases because calcifications (one case) and air bubbles within an abscess (one case) were not detectable.  相似文献   
87.
Is ACTH a key to understanding anticonvulsant action?   总被引:2,自引:1,他引:1  
Adrenocorticotrophin hormone (ACTH) has been used as an anticonvulsant for many years. In this paper, the use of ACTH in 23 children with intractable epilepsies is described. It was found that ACTH worked most effectively when the EEG showed benzodiazepine sensitivity. A mechanism of action of ACTH is proposed.  相似文献   
88.
Hepatic metastases studied with MR and CT   总被引:1,自引:0,他引:1  
Heiken  JP; Lee  JK; Glazer  HS; Ling  D 《Radiology》1985,156(2):423-427
Examinations of the liver using magnetic resonance (MR) and computed tomography (CT) were performed on 50 patients with hepatic metastases. MR and CT were comparable in their ability to detect metastases, which generally appeared hypointense compared with normal liver parenchyma on T1-weighted MR images and hyperintense on T2-weighted images. The MR imaging techniques that were most reliable in detecting metastases were inversion recovery and a relatively T2-weighted, spin-echo technique (TR = 1,500 msec, TE = 60 msec). We conclude that CT, because of its shorter imaging time, greater spatial resolution, and lower cost, should remain the preferred screening test for hepatic metastases. MR imaging should be reserved for patients with equivocal CT findings and for patients in whom there is persistent clinical suspicion of hepatic metastases despite a negative CT examination.  相似文献   
89.
To investigate the sodium magnetic resonance (MR) imaging characteristics of acute vasogenic edema, an experimental canine model was developed. Vasogenic edema was produced in the hemisphere of the dogs by the intraarterial infusion of hypertonic mannitol (25%). This solution opens the blood-brain barrier, allowing the influx of water, electrolytes, and proteins into the brain. The main advantage of this model over the established "cold injury" model is the lack of associated brain necrosis. Two patients with chronic vasogenic edema secondary to well-circumscribed meningiomas also underwent MR imaging. The sodium signal was markedly elevated in both clinical and experimental studies of vasogenic edema fluid compared with signal in healthy brain tissue. Extracellular sodium associated with vasogenic edema displayed MR imaging characteristics similar to that of sodium in serum. There was a trend toward a shortened T2 in edema fluid secondary to the presence of serum macromolecules.  相似文献   
90.
The efficacy of intra-articular glucocorticoid injections in the early phase of knee joint synovitis was studied in 79 children with juvenile chronic arthritis (42 girls and 37 boys). Half of the injections were given within the first six months from the onset of the disease. The probability of a patient staying in remission was much higher in triamcinolone-treated patients than in patients receiving methylprcdni-solone ( p <0.0005, Breslow statistics). Using multivariate analysis there was a significant association between the length of remission and the synovial fluid polymorphonuclcar leucocyte proportion (SF-PMN%. Patients with a high SF-PMN% tended to have shorter remissions than those with a low SF-PMN% (improvement of the fit in stcpwise model: chi-square = 8.81, p <0.005). The difference between triamcinolone and methylprednisolone groups was still clearly evident two years after injection.  相似文献   
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