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Hans-Georg Elias Daniel C. Chung Nobuo Donkai Goetz P. Hellmann Karel Solc Katsutoshi Nagai 《Macromolecular chemistry and physics.》1987,188(3):537-560
1-O-3-(4-Vinylphenyl)propyl-β-D -glucopyranose ( 1 ) undergoes in water a closed association under formation of N-mers. The unimer/N-mer association is directly visible in the Schlieren pattern of ultracentrifugal synthetic boundary experiments. Association numbers and mass-concentration-based equilibrium constants of association were calculated from the variation of N-mer concentrations with unimer concentrations and from the concentration dependence of inverse apparent average molar masses as measured by both vapor phase osmometry and sedimentation equilibrium. Association numbers were also calculated from the combination of sedimentation coefficients with diffusion coefficients, sedimentation coefficients with intrinsic viscosities, and diffusion coefficients with interinsic viscosities as well as from the dependence of apparent mass-average molar masses on inverse apparent number-average molar masses. All methods gave in general different association numbers and equilibrium constants. The effect, which was not found for other non-ionic amphiphiles, is probably due to the existence of consecutive equilibria between the unimer and a low molar mass P-mer which associates to a higher molar mass R-mer. Viscosity data are in agreement with the picture of a spherical micelle for the dominant P-mers with about 10 water molecules per glucose residue. The micellization of 1 is both enthalpy- and entropy-driven, in contrast to the micellization of 1-O-octyl-β-D -glucopyranose which is a strictly entropy-driven process. 相似文献
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BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
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The efficacy of betanecholchloride in the postoperative treatment of bladder dysfunction is controversial. We therefore performed
a comparative study on the effect of this therapy for the prophylaxis of detrusor hypotonia after Wertheim-Meigs operation.
Forty patients with cervical cancer FIGO stage Ib/IIa were divided into two study groups. The control group (24 patients)
only received betanecholchloride if the residual urine persisted above 50 ml after the 10th postoperative day. The study group
(16 patients) received 50 mg betanecholchloride three times a day from the 3rd postoperative day onward. In this group postoperative
catheter treatment, and consequently hospital stay, were significantly shorter (9.6 versus 13.3 days and 15.5 versus 18.6
days). The residual urinary volume normalized faster (8.0 versus 13.0 days) and the rate of cystitis was lower (18.8 versus
25%). According to our study, a prophylactic application of the parasympathomimetic drug betanecholchloride diminishes postoperative
complications associated with bladder dysfunction after Wertheim-Meigs operation.
EDITORIAL COMMENT: Bladder dysfunction plays an important role after radical hysterectomy. The authors present data indicating
improved and quicker resumption of bladder function following radical hysterectomy with early administration of betanecholchloride,
versus use of the medication only when indicated by elevated postvoid residual. Although the study is not a double-blinded
placebo-controlled trial, the patients who received beta-necholchloride from postoperative day 3 had significantly decreased
postoperative catheter treatment, earlier resumption of adequate bladder emptying defined as a postvoid residual of less than
50 ml, decreased incidence of bladder infection and shorter hospital stay. This information is encouraging for this subset
of patients, who characteristically are at high risk for long-term bladder dysfunction. Further studies in this area are needed
to clarify therapeutic options to improve patients’ quality of life, specifically in regard to bladder function following
treatment of their cancer. 相似文献
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B A Fallon R Campeas F R Schneier E Hollander J Feerick J Hatterer D Goetz S Davies M R Liebowitz 《The Journal of neuropsychiatry and clinical neurosciences》1992,4(1):70-75
In a preliminary trial, five oral-clomipramine-refractory patients with obsessive-compulsive disorder (OCD) were treated openly with 14 intravenous clomipramine infusions each. Using standardized assessments, three patients were rated as much improved, one as unchanged, and one as minimally improved. Statistically significant improvements were noted on both the Yale-Brown Obsessive Compulsive Scale and the NIMH Global OCD scores. No patient discontinued treatment because of side effects. Although the results are provocative in that three of five patients were much improved at the end of the protocol, conclusions about preferential efficacy for the intravenous route must await a placebo-controlled trial. 相似文献
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Christopher G Goetz Stanley Fahn Pablo Martinez-Martin Werner Poewe Cristina Sampaio Glenn T Stebbins Matthew B Stern Barbara C Tilley Richard Dodel Bruno Dubois Robert Holloway Joseph Jankovic Jaime Kulisevsky Anthony E Lang Andrew Lees Sue Leurgans Peter A LeWitt David Nyenhuis C Warren Olanow Olivier Rascol Anette Schrag Jeanne A Teresi Jacobus J Van Hilten Nancy LaPelle 《Movement disorders》2007,22(1):41-47
This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process. 相似文献