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991.
Three new secoiridoids, nuezhenelenoliciside (1), isojaslanceoside B (2), 6′-O-trans-cinnamoyl-secologanoside (3), were isolated from the dried fruits of Ligustrum lucidum. Their structures were elucidated by comprehensive spectroscopic analysis. Among them, 1 featured a rare rearrangement product of secoiridoid, which underwent the cleavage of chemical bond between C-1 and O-2, and the reformation of a new iridoid ring between C-8 and O-2. In addition, all compounds were tested for their osteogenic activity on pre-osteoblastic MC3T3-E1 cells. As a result, 1 and 3 exhibited potent effects on promoting cell proliferation of pre-osteoblast cells.  相似文献   
992.

Marine organisms such as marine sponges and soft corals are valuable sources of pharmacologically active secondary metabolites. In our ongoing research on the discovery of new secondary metabolites from marine organisms, two new pyrrolo-2-aminoimidazoles, clathriroles A (1) and B (2), were isolated from the water-soluble portion prepared from the methanol and acetone (2:1) extract of the marine sponge, Clathria prolifera, collected in Myanmar. The chemical structures of the isolated compounds were determined using extensive spectroscopic techniques, including NMR, HRESIMS, IR, and optical rotation, and comparisons with the reported literature. The spectroscopic analyses of 1 and 2 suggested that 1 is an enantiomer of antifungal N-methylmanzacidin C isolated from the marine sponge Axinella brevistyla, whereas 2 is a diastereomer of manzacidin D at C-11 isolated from the marine sponge Astrosclera willeyana. To the best of our knowledge, this is the first report of the isolation of the pyrrolo-2-aminoimidazole compounds from C. prolifera. Furthermore, in contrast to the potency of N-methylmanzacidin C against Saccharomyces cerevisiae, the antifungal assay revealed that 1 and 2 lack any activity against this strain. Thus, these observations may suggest that the absolute configurations at both C-9 and C-11 play an important role in controlling the antifungal activity of this type of compound.

  相似文献   
993.
994.

Objectives

To determine the preference of mothers in Hong Kong and their willingness to pay (WTP) for human papillomavirus (HPV) vaccination for their daughters.

Method

A discrete choice experiment survey with a two-alternative study design was developed. Data were collected from pediatric specialist outpatient clinics from 482 mothers with daughters aged between 8 and 17 years. Preferences of the four attributes of HPV vaccines (protection against cervical cancer, protection duration, side effects, and out-of-pocket costs) were evaluated. The marginal and overall WTP were estimated using multinomial logistic regression. A subgroup analysis was conducted to explore the impact of socioeconomic factors on mothers’ WTP.

Results

Side effects, protection against cervical cancer, protection duration, and out-of-pocket cost determined the decision to receive or not receive the vaccine. All attributes had a statistically significant effect on the preference of and the WTP for the vaccine. Maximum WTP for ideal vaccines (i.e., 100% protection, lifetime protection duration, and 0% side effects) was HK$8976 (US $1129). The estimated WTP for vaccines currently available was HK$1620 (US $208), lower than the current market price. Among those who had a monthly household income of more than HK$100,000 (US $12,821), the WTP for vaccines currently offered was higher than the market price.

Conclusions

This study provides new data on how features of the HPV vaccine are viewed and valued by mothers by determining their perception of ideal or improved and current vaccine technologies. These findings could contribute to future policies on the improvement of HPV vaccine and be useful for the immunization service in Hong Kong.  相似文献   
995.

Background

EQ-5D-5L valuation studies previously reported many inconsistent responses in time trade-off (TTO) data. A number of possible elements, including ordering effects of the valuation tasks, mistakes at the sorting question, and interviewers’ (learning) effects, may contribute to their inconsistency.

Objectives

This study aimed to evaluate the effect of two modifications on consistency of TTO data in The Netherlands (NL) and Hong Kong (HK): (1) separating the valuation of the Better than Dead (BTD) and Worse than Dead (WTD) states; and (2) Implementation of feedback (FB) module by offering an opportunity to review TTO responses.

Methods

A crossover design with two study arms was used to test the effect of the modifications. In each jurisdiction, six interviewers were involved where half the interviewers started using the standard version, and the other half started with the split version. Each version was switched after every 25 (NL) or 30 (HK) interviews until 400 interviews were completed.

Results

In the NL and HK, 404 and 403 respondents participated, respectively. With the use of the FB module, the proportion of respondents with inconsistent responses was lowered from 17.8% to 10.6% (P < 0.001) in NL and from 31.8% to 22.3% (P = 0.003) in HK. The result of separating the valuation of BTD and WTD states was not straightforward because it reduced the inconsistency rate in NL but not in HK.

Conclusions

The results support implementation of the FB module to promote the consistency of the data. The separation of the BTD and WTD task is not supported.  相似文献   
996.
BACKGROUND: Patients with rheumatoid arthritis (RA) provide an important opportunity for understanding care of patients with a serious chronic condition. OBJECTIVES: We sought to characterize the complexity of care for patients with RA, including metrics describing the patient, the disease, and use of the health care system across time and place. METHODS: We undertook a prospective cohort study of 568 community-dwelling patients with RA by using observational data from clinically detailed telephone interviews at baseline and 2 years later in addition to medical record abstraction. Health status, comorbidity, use of disease-modifying antirheumatic drugs, visits, providers, provider types, encounter settings, and the discontinuity between patients and providers were studied. RESULTS: Within a 12-month window, 568 patients had 8686 outpatient encounters with the health care system with a mean of 3.41 unique providers per patient associated with a mean of 5 primary care and 6 rheumatologist visits. Half did not see a primary care physician, and 20% did not see a rheumatologist during 6-month periods despite their use of potentially toxic drugs, a mean of 4 comorbidities and progressive RA. Over the course of 24 months, 29% of patients changed their primary care provider, and 15% changed their rheumatologist. Patients were moderately impaired with mean SF-12 physical component score 37 (SD, 9). CONCLUSION: Patients with RA have frequent encounters with multiple providers and also frequent discontinuity of care. Recognizing the complexity of the care of patients with a chronic disease across multiple dimensions provides an opportunity to better understand challenges and opportunities in delivering high quality care.  相似文献   
997.
OBJECTIVE: To examine the effect of ankle continuous passive motion on the reflex excitability and overall hypertonia of calf muscles in individuals with chronic spinal cord injury and without physical disabilities. DESIGN: Two-way repeated measure experimental design. SETTING: Inpatient rehabilitation department in general hospital. SUBJECTS: The spinal cord injury group comprised eight individuals with chronic complete spinal cord injury and the control group comprised eight healthy people without physical disabilities. An additional eight healthy people were recruited as the sham group. INTERVENTIONS: Each subject received 60 min of continuous passive motion on the ankle joint. MAIN MEASURES: The H-reflex of the soleus muscle was elicited by tibia nerve stimulation just before, immediately after, and 10 min after continuous passive motion. The Modified Ashworth Scale (MAS) score at the ankle joint was recorded for the spinal cord injury group just before and 10 min after continuous passive motion therapy. RESULTS. After 60 min of continuous passive motion of the ankle joint, the H-reflex amplitude at the soleus muscle was depressed in individuals with and without spinal cord injury (77.46 +/- 32.64%, P = 0.047 and 51.76 +/- 26.74% of initial, P<0.0001, respectively). This depression persisted up to 10 min after continuous passive motion only in individuals without spinal cord injury. In individuals with spinal cord injury, the median of MAS scores decreased from 2 to 1.25 after continuous passive motion. CONCLUSION: Sixty minutes of continuous passive motion of the ankle joint decreased reflex excitability and overall hypertonia in people with or without spinal cord injury. The depression of overall hypertonia persisted longer than the reflex excitability in people with spinal cord injury.  相似文献   
998.
999.
PURPOSE: To evaluate the effectiveness of two marketed home tooth-whitening products. METHODS: A randomized controlled clinical trial involving 87 adults who were randomly allocated into one of three groups: (1) 6% hydrogen peroxide whitening strips, (2) 18% carbamide peroxide whitening gel, and (3) a placebo (fluoride toothpaste) control group. Subjects were instructed individually and then used the given product daily for 2 consecutive weeks. Color was determined in brightness (L*), yellowness (b*) and redness (a*) [color space] at baseline and 8 weeks after dispensing the product by employing a high resolution digital camera (Fuji HC1000 CCD) to image the subject's anterior maxillary teeth under standard polarized lighting conditions. The subjects also completed a questionnaire on self-satisfaction with the treatment outcome. RESULTS: One-way ANOVA (Bonferroni test) demonstrated significant differences in color between the three groups with changes in brightness (L*, P< 0.001), yellowness (b*, P< 0.001) and redness (a*, P < 0.001). Changes in L* a* b* was greatest among those who used the 6% hydrogen peroxide whitening strips. Subjects in the whitening strip group also rated that product significantly (P < 0.01) more favorably than other groups with respect to the amount of whiteness improvement, as well as whitening satisfaction and overall impression while there is no significant difference between the whitening gel and the placebo groups.  相似文献   
1000.
The purpose of this clinical case report was to describe the kinematic variables of movement that best discriminated between asymmetrical and symmetrical mandibular excursion patterns in a patient with myogenic temporomandibular dysfunction. Two mandibular movements (deemed to be asymmetrical and symmetrical by both patient and physiotherapist) were each recorded six times on three occasions at six, twelve, and 15 weeks after commencement of an exercise programme. The mandibular movements were captured with a 12-camera Motion Analysis System (Motion Analysis Corp., Santa Rosa, CA) with kinematic variables expressed in six degrees-of-freedom. A two-way analysis of variance (ANOVA) for repeated measures was used to analyze the data. The asymmetrical pattern was characterized by increased axial rotation and decreased sagittal rotation but with no differences in translation values when compared to those of the symmetrical pattern. The results support the clinician's and patient's judgment regarding differences in quality of mandibular excursion patterns made over the course of time.  相似文献   
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