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排序方式: 共有3466条查询结果,搜索用时 15 毫秒
51.
Hymas DC Mamalis N Pratt DV Scott MH Anderson RL Langer PD 《Ophthalmic plastic and reconstructive surgery》1999,15(2):139-142
PURPOSE: To describe a 14-year-old boy with a 1-month history of a rapidly growing, nontender, lower eyelid mass. METHODS: The specimen was studied using light microscopy. RESULTS: Although magnetic resonance imaging suggested a chronic vascular lesion, histopathologic analysis after excisional biopsy was consistent with nodular fasciitis. CONCLUSIONS: Nodular fasciitis is a relatively common soft-tissue lesion and represents a benign, reactive process. Lesions in the head and neck develop more frequently in children and adolescents than in adults, but periorbital lesions are uncommon. This is the first reported case of nodular fasciitis of the lower eyelid in a pediatric patient. 相似文献
52.
Lowe G Droz AS Vilaivan T Weaver GW Tweedale L Pratt JM Rock P Yardley V Croft SL 《Journal of medicinal chemistry》1999,42(6):999-1006
A range of (2,2':6',2'-terpyridine)platinum(II) complexes are shown to possess antiprotozoal activity in vitro against Leishmania donovani, Trypanosoma cruzi, and Trypanosoma brucei,the causative organisms of tropical diseases leishmaniasis and trypanosomiasis. The best compounds caused 100% and 78% inhibition of growth of the intracellular amastigote forms of L. donovani and T. cruzi, respectively, at a concentration of 1 microM and 100% inhibition of growth of the bloodstream trypomastigote forms of T. brucei at a concentration of 0.03 microM. The results obtained with complexes in which the fourth ligand to platinum(II) is capable of being substituted with a substitution inert hydroxyethanethiolate complex are compared. The ammine complexes show high antiprotozoal activity suggesting that the trans influence of the 2,2':6',2'-terpyridine ligand has a profound effect on the ease of displacement of the fourth ligand in (2,2':6',2' -terpyridine)platinum(II) complexes, although nonbonded interaction between the ammine ligand and the 6 and 6' ' hydrogens probably also weakens the ligation to Pt(II). 相似文献
53.
The measurement of tubal perfusion pressures (TPP) is a recent advance in the field of gynaecoradiology. Measurement of TPP involves a standardized technique using transcervically placed tubal catheters which is reviewed in detail. TPP assesses the functional status of the Fallopian tubes, i.e. their ability to permit pregnancy. Infertile patients with normal TPP demonstrated a higher pregnancy rate (10 out of 23) than patients with elevated TPP (four out of 24, P < 0.05). Analysis of patients who had undergone a laparoscopy as well as measurement of TPP suggest that elevated TPP are highly indicative of tubal endometriosis. Tubal catheterization with wireguides was successful in reducing mildly elevated TPP. The impact of this procedure on pregnancy rates is not known. The use of the gynaecoradiological techniques discussed in this paper has reduced the need for diagnostic laparoscopy at our centre by >60%. This was achieved without compromise in pregnancy rates and has resulted in a considerable reduction in cost. 相似文献
54.
Hummer G Garde S García AE Pohorille A Pratt LR 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(17):8951-8955
A molecular model of poorly understood hydrophobic effects is heuristically developed using the methods of information theory. Because primitive hydrophobic effects can be tied to the probability of observing a molecular-sized cavity in the solvent, the probability distribution of the number of solvent centers in a cavity volume is modeled on the basis of the two moments available from the density and radial distribution of oxygen atoms in liquid water. The modeled distribution then yields the probability that no solvent centers are found in the cavity volume. This model is shown to account quantitatively for the central hydrophobic phenomena of cavity formation and association of inert gas solutes. The connection of information theory to statistical thermodynamics provides a basis for clarification of hydrophobic effects. The simplicity and flexibility of the approach suggest that it should permit applications to conformational equilibria of nonpolar solutes and hydrophobic residues in biopolymers. 相似文献
55.
Brownson RC Mack NE Meegama NI Pratt M Brownson CA Dean C Dabney S Luke DA 《Health education research》1996,11(4):479-486
Numerous community-based prevention projects, with significant media components, have been conducted over the past decade. Multiple evaluation strategies have been used to document the effectiveness of these interventions, including intermediate measures of community impact such as assessment of media coverage. As part of the evaluation of a community-based intervention (the Bootheel Heart Health Project), dissemination of information on cardiovascular disease (CVD) was measured through a media content analysis of newspapers. Data were analyzed from 23 newspapers in six rural counties in southeastern Missouri for the period October 1988 through August 1993. An increase was observed in CVD-related coverage in the pre-intervention period (mean articles per month = 31.5) compared with the post-intervention period (mean articles per month = 50.7) (F = 10.2; P = 0.003). In supporting data from a separate randomized risk factor survey of 1510 residents in the same area, respondents reported hearing of heart health coalitions primarily through local newspapers. The current study documents increasing print media coverage of cardiovascular health issues in a high-risk, rural area and shows that media content analysis can be a useful evaluation tool in community-based interventions. 相似文献
56.
57.
An initiative which targets resources towards chiropody patients with the greatest needs has been taking place in Nottinghamshire during the past three years. Ian Morton and Peter Pratt describe its progress and outline its new goals. 相似文献
58.
59.
William R. Crom William E. Evans Charles B. Pratt Neil Senzer Marilyn Denison Alexander A. Green F. Ann Hayes Gary C. Yee 《Cancer chemotherapy and pharmacology》1981,6(1):95-99
Summary The disposition of cisplatin was evaluated in 28 children and adolescents with cancer, as part of a phase II clinical trial. Patients received either 30 mg/m2 (11) or 90 mg/m2 (17) of cisplatin as a 6-h IV infusion. Serum samples and divided urine collections were obtained over 48 h following completion of the cisplatin infusion, and were assayed in duplicate for total platinum by atomic absorption spectrophotometry. Serum samples obtained up to 4 h after three cisplatin infusions were assayed for parent (free) cisplatin following ultrafiltration. The mean (±SE) elimination half-life of free cisplatin in serum was 1.3 (±0.4) h. Serial serum concentrations of total platinum following 90 mg/m2 dosages were adequately described by a biexponential equation. The mean (±SE) serum T1/2 of total platinum was 0.42 (±0.10) h and the mean (±SE) T1/2 was 44.43 (±8.24) h. The intercompartment distribution rate constants of a two-compartment kinetic model indicate extensive tissue accumulation of total platinum, with a rate of transport into tissue compartments (K12) that is about six times the rate of transport out of tissues (K21). The mean (±SE) renal clearance of total platinum from 0–3 h was 37.36 (±11.96) ml/min/m2 and 35.8 (±13.6) ml/min/m2 for the 30 mg/m2 and 90 mg/m2 groups, respectively. This value decreased to 3.25 (±0.94) and 2.16 (±0.4) ml/min/m2 for the two groups by the 6–12 h interval, and remained between 1 and 3 ml/min/m2 for the duration of the observation period. The ratio of total plantinum clearance to creatinine clearance decreased significantly(P<0.05) beginning 3 h post-infusion. The change in renal clearance of total platinum is apparently a function of two independent first-order processes for renal clearance of parent drug and cisplatin metabolites. 相似文献
60.