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81.

Background  

Although self-tests are increasingly available and widely used, it is not clear whether their use is beneficial to the users, and little is known concerning the determinants of self-test use. The aim of this study was to identify the determinants of self-test use for cholesterol, glucose, and HIV, and to examine whether these are similar across these tests. Self-testing was defined as using in-vitro tests on body materials, initiated by consumers with the aim of diagnosing a particular disorder, condition, or risk factor for disease.  相似文献   
82.
83.
Community health centers and community development financial institutions share similar origins and missions and are increasingly working together to meet community needs. Addressing the social and economic determinants of health is a common focus. The availability of new federal grants and tax credits has led these financial institutions to invest in the creation and expansion of community health centers. This article reviews the most recent trends in these two sectors and explores opportunities for further collaboration to transform the health and well-being of the nation's low-income communities.  相似文献   
84.
85.
A series of p-substituted glycidyl phenyl ethers
  • 1 IUPAC nomenclature: 2,3-epoxypropyl phenyl ether.
  • with electron donor groups was prepared using a multistep synthetic method. These compounds were polymerized using four of the most common aluminium-based coordinative initiators, (C2H5)3Al/H2O (the Vandenberg catalyst), (C2H5)3Al/CH3COCH2COCH3/H2O (the Vandenberg chelate catalyst), [(CH3)2CHO&]2Al? O? Zn? O? Al[OCH(CH3)2]2 (the Teyssié catalyst) and [(CH3)2CHO]3AV/ZnCI2 (the Price catalyst), all with different Lewis acid character. The influence of the electron-donor group on the characteristics and conversion was studied. Generally speaking, both the Vandenberg and the Teyssié catalysts yield mostly an insoluble polymer fraction, whereas the Price catalyst was shown to be the most stereoselective catalyst. Moreover, the Vandenberg chelate catalyst gave the highest molecular weight, the Price catalyst the lowest. Thermal characteristics of polymers were studied by means of differential thermal analysis to obtain glass transition temperatuures, melting temperatures and fusion enthalpies.  相似文献   
    86.

    Purpose

    Because of the evolutionary loss of the uricolytic pathway, humans accumulate poorly soluble urate as the final product of purine catabolism. Restoration of uricolysis through enzyme therapy is a promising treatment for severe hyperuricemia caused by deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). To this end, we studied the effect of PEG conjugation on the activity and stability of the enzymatic complement required for conversion of urate into the more soluble (S)-allantoin.

    Methods

    We produced in recombinant form three zebrafish enzymes required in the uricolytic pathway. We carried out a systematic study of the effect of PEGylation on the function and stability of the three enzymes by varying PEG length, chemistry and degree of conjugation. We assayed in vitro the uricolytic activity of the PEGylated enzymatic triad.

    Results

    We defined conditions that allow PEGylated enzymes to retain native-like enzymatic activity even after lyophilization or prolonged storage. A combination of the three enzymes in an appropriate ratio allowed efficient conversion of urate to (S)-allantoin with no accumulation of intermediate metabolites.

    Conclusions

    Pharmaceutical restoration of the uricolytic pathway is a viable approach for the treatment of severe hyperuricemia.
      相似文献   
    87.
    Starting from 4-methoxycarbonylphenyl glycidyl ether and unfunctionalized phenyl glycidyl ether, samples of highly regio- and stereoregular linear homo- and copolymers were synthesized using the ionic coordinative initiator system aluminium isopropoxide/ZnCl2. The polymers were first transformed into carboxylic acid derivatives and then into highly reactive carboxylic acid chlorides with high yields and conversions. The use of all these synthesized polymers was tested by transforming them into the corresponding 4-nitrobenzyl ester using different synthetic procedures. Finally, the scope of the methodology studied was tested by using it to synthesize a set of new polymers containing different complex groups such as: 18-crown-6, biphenyl-4-carbonitrile, anthraquinone, (1R)-nopol, (-)-inosine and 4-dodecylaniline, which are in general obtained with good yields and conversions.  相似文献   
    88.
    Genetic manipulation studies in mice at both the MCH receptor 1 (MCHR1) as well as the MCH peptide levels have implicated MCHR1 as a key player in energy homeostasis. The phenotype exhibited by these studies, that is, increased metabolic rate, resistance to high fat diet, and subsequent weight loss, has spurred considerable efforts to develop antagonists of MCHR1. In continuation of efforts directed toward this goal, the present work capitalizes on the putative binding mode of an MCH antagonist, resulting in the identification of several novel chemotypes that are potent and selective MCHR1 antagonists. In addition, the favorable pharmacokinetics of representative examples has allowed for the evaluation of an MCHR1 antagonist in a high fat diet-induced obese rodent model of obesity. The tolerability of the right-hand side of the template for diverse chemotypes accompanied by favorable effects on weight loss enhances the attractiveness of this template in the pursuit toward development of effective anti-obesity agents.  相似文献   
    89.
    90.
    Introduction Excision followed by RFA (eRFA) may allow improved cosmesis while ensuring negative margins in patients with breast cancer. This technique utilizes heat to create an additional tumor-free zone around the lumpectomy cavity. We hypothesized that eRFA will decrease the need for re-excision of inadequate margins.Methods Between July 2002 and January 2005, we conducted a multiphase trial of RFA of prophylactic mastectomy specimens and of women desiring lumpectomy. In both models, a lumpectomy was performed, the RFA probe was deployed 1 cm circumferentially into the walls of the lumpectomy cavity and maintained at 100°C for 15 min. Whole mount slides were used to measure the zone of ablation for ex vivo specimens. Hematoxylin and eosin staining of in vivo lumpectomy margins <3 mm was considered inadequate.Results Nineteen prophylactic mastectomy ablations revealed a consistent perimeter of ablation. Forty-one patients (mean age 63 ± 14 years) had an average tumor size of 1.6 ± 1.5 cm underwent in vivo eRFA, and 25% had inadequate margins: one focally positive, one <2 mm, eight <1 mm and one grossly positive. Only the grossly positive margin was re-excised. Overall complication rate of in vivo ablations was 7.5%. Twenty-four of 41 patients did not have post-eRFA XRT. No in-site local recurrences have occurred during a median follow-up of 24 months (12–45 months). Two patients have occurred elsewhere.Conclusions The ex vivo ablation model reliably created a 5–10 mm perimeter of ablation. In vivo, this zone reduced the need for re-excision for inadequate margins by 91% (10/11). Short-term follow-up suggests that eRFA could reduce re-excision surgery and local recurrence.  相似文献   
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