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901.
Roth T  Stubbs C  Walsh JK 《Sleep》2005,28(3):303-307
OBJECTIVE: Evaluate the efficacy of ramelteon, an MT/1MT2-receptor agonist, for the treatment of transient insomnia in healthy adults. DESIGN: Randomized, double-blind, placebo-controlled design using a model of transient insomnia related to sleeping in a novel environment. SETTING: Fourteen sleep research centers. PARTICIPANTS: Healthy adults (N=375; 228 women), aged 35 to 60 years, who had never previously slept in a sleep laboratory and had a reported usual sleep duration of 6.5 to 8.5 hours and usual bedtime between 8:30 PM and midnight. INTERVENTIONS: Single administration of ramelteon (16 or 64 mg) or placebo 30 minutes before bedtime. OUTCOME MEASURES: Primary efficacy measure was latency to persistent sleep. Also evaluated were total sleep time, wake after sleep onset, percentage of each sleep stage, subjective estimates of sleep from postsleep questionnaire, number of awakenings, and subjective number of awakenings. Residual effects were assessed via Digit Symbol Substitution Test and postsleep questionnaire. RESULTS: Participants in ramelteon-treated groups had significantly shorter latency to persistent sleep relative to placebo. They also were associated with significantly longer total sleep time. Wake after sleep onset and time spent in each sleep stage were not significantly different from placebo. The use of ramelteon (16 mg) was associated with a shorter subjective sleep latency compared to placebo. Other subjective measures of sleep did not differ significantly from placebo. Digit Symbol Substitution Test scores did not differ significantly among the 3 groups, but the use of the 64-mg [corrected] dose was associated with subjective reports of impairment in the morning. CONCLUSIONS: Ramelteon significantly improved latency to persistent sleep and total sleep time in this model of transient insomnia in healthy adults. No dose-related differences in latency to persistent sleep were observed, and both doses were well tolerated.  相似文献   
902.
Surgical site infections (SSIs) are serious adverse events hindering surgical patients’ recovery. In Australia and New Zealand, SSIs are a huge burden to patients and healthcare systems. A bundled approach, including pre‐theatre nasal and/or skin decolonization has been used to reduce the risk of staphylococcal infection. The aim of this review is to assess the effectiveness of the bundle in preventing SSIs for cardiac and orthopaedic surgeries. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. Published literature was searched in PubMed, Embase and Cochrane Library of Systematic reviews. Identified articles were selected and extracted based on a priori defined Population‐Intervention‐Comparator‐Outcome and eligibility criteria. Data of randomized controlled trials (RCTs) and comparative observational studies were synthesized by meta‐analyses. Quality appraisal tools were used to assess the evidence quality. The review included six RCTs and 19 observational studies. The bundled treatment regimens varied substantially across all studies. RCTs showed a trend of Staphylococcus aureus SSIs reduction due to the bundle (relative risk = 0.59, 95% confidence interval (CI) = 0.33, 1.06) with moderate heterogeneity. Observational studies showed statistically significant reduction in all‐cause and S. aureus SSIs, with 51% (95% CI = 0.41, 0.59) and 47% (95% CI = 0.35, 0.65), respectively. No publication biases were detected. SSIs in major cardiac and orthopaedic surgeries can be effectively reduced by approximately 50% with a pre‐theatre patient care bundle approach.  相似文献   
903.
The Rh blood group antigen e is of high incidence and has many epitopes. Partial expression may occur, more commonly in black persons. Individuals with e variant phenotypes can make antibodies to epitopes they lack. While some of these antibodies may be specific for an antigen, e.g., hrB, others, like anti-Rh17 (anti-Hro), show broader specificity, compatible only with D-- and Rhnull red blood cells (RBCs). Anti-Rh17 in persons of the D-- phenotype has been reported to cause mild to fatal HDN. We report an example of anti-Rh17 produced by a black female with an e variant RBC phenotype that caused moderate HDN. A panel of seven monoclonal anti-e demonstrated her RBCs carried a variant e antigen, and her genotype was RHD, RHce by PCR-RFLP analysis. Amniotic fluid with.OD450 values from 30 to 35 weeks' gestation predicted moderate HDN probability by the Liley method. At 38+ weeks, a viable 3165 g female infant was delivered. The infant's direct antiglobulin test was 2+ with anti-IgG. Total bilirubin rose to 14.2 mg/dL within 48 hours. Indirect bilirubin peaked at 14.7 mg/dL. The bilirubin responded to triple phototherapy. The infant was discharged on day 6. Potential for infant morbidity due to anti-Rh17- mediated HDN and the importance of specifying risks to women with this antibody if they contemplate pregnancy are discussed.  相似文献   
904.
Using mouse BAC clones spanning an imprinted interval of proximal mouse chromosome 7 and the genomic sequence of the related interval of human chromosome 19q13.4, we have identified a novel mouse gene, Usp29 (ubiquitin-specific processing protease 29), near two known imprinted genes, Peg3 and Zim1. Gene Usp29 is located directly adjacent to Peg3 in a "head-to-head" orientation, and comprises exons distributed over a genomic distance of at least 400 kb. A similar human gene is also found in the homologous location in human chromosome 19q13.4. The mouse Usp29 gene is also imprinted and is transcribed mainly from the paternal allele with highest expression levels in adult brain, especially in the cerebral cortex and hippocampus, and in the forebrain, face, and limb buds of midgestation mouse embryos. Analysis of a full-length 7.6-kb cDNA clone revealed that Usp29 encodes an 869-amino-acid protein that displays significant homology with yeast and nematode ubiquitin carboxyl-terminal hydrolases. These data suggest that, like the candidate Angelman syndrome gene Ube3a (ubiquitin ligase), Usp29 may represent another imprinted gene involved in the ubiquitination pathway. This identification of a third imprinted gene, Usp29, from the Peg3/Zim1-region confirms the presence of a conserved imprinted domain spanning at least 500 kb in the proximal portion of mouse chromosome 7 (Mmu7).  相似文献   
905.
The increase in gastrointestinal epithelial tissue mass and the development of the gut can occur through three main mechanisms, namely elevated cell production from the intestinal crypts, by raised crypt number, which occurs through the process of crypt fission or by altered apoptosis. The small bowel and the colon have various rates of these, which were studied in rats of various ages. Wistar rats were fed ad libitum, and were killed at 3, 4, 6, 9, 12, 18, 26 and 48 weeks of age. Tissue was later stained and microdissected and the number of native mitoses and apoptotic figures per crypt and the percentage of crypts in fission were determined. There was an almost linear increase in body weight from 3 to 9 weeks, followed by a more gradual rise until 18 weeks. The weight of the stomach and the small intestine reached maximum values at 9 weeks, whereas the caecum and the colon approached this at 12 weeks. Mitotic activity per crypt in the small intestine increased from 3.8 +/- 0.1 at 3 weeks to 7.8 +/- 0.4 mitoses per crypt (P < 0.001) at 9 weeks and then decreased slightly; crypt fission increased from 4.6% +/- 0.8 at 3 weeks to 8.4 +/- 0.9% at 6 weeks and then decreased gradually reaching a value of 1.5 +/- 0.4% at 48 weeks. Apoptosis also peaked at 6 weeks and was then very low. In the colon, the proliferation decreased from 4.2 +/- 0.2 mitoses per crypt in the young (3 weeks) rat and reached a plateau by 9 weeks (2.5 +/- 0.1 mitoses per crypt, P < 0.001). Crypt fission also declined rapidly in the first 9 weeks (from 67.6 +/- 4.2 to 23.1 +/- 4.6%, P < 0.01) and then continued to decline, although at a lower rate. The crypt fission index at 48 weeks was 9.8 +/- 1.0. Apoptosis in the colon persisted throughout the duration of the study, 0.19 +/- 0.06 apoptotic bodies per crypt were seen at week 48. The development of the small intestine is more dependent on cell proliferation, whereas in the colon crypt fission is far more predominant, with the colon having fission indices approximately six times greater than those of the small intestine. Proliferative activity in the colon was approximately half that of the small intestine.  相似文献   
906.

Background

Sufficient, safe, continuously available drinking water is important for human health and development, yet one in three handpumps in sub-Saharan Africa are non-functional at any given time. Community management, coupled with access to external technical expertise and spare parts, is a widely promoted model for rural water supply management. However, there is limited evidence describing how community management can address common hardware and management failures of rural water systems in sub-Saharan Africa.

Methods

We identified hardware and management rehabilitation pathways using qualitative data from 267 interviews and 57 focus group discussions in Ghana, Kenya, and Zambia. Study participants were water committee members, community members, and local leaders in 18 communities (six in each study country) with water systems managed by a water committee and supported by World Vision (WV), an international non-governmental organization (NGO). Government, WV or private sector employees engaged in supporting the water systems were also interviewed. Inductive analysis was used to allow for pathways to emerge from the data, based on the perspectives and experiences of study participants.

Results

Four hardware rehabilitation pathways were identified, based on the types of support used in rehabilitation. Types of support were differentiated as community or external. External support includes financial and/or technical support from government or WV employees. Community actor understanding of who to contact when a hardware breakdown occurs and easy access to technical experts were consistent reasons for rapid rehabilitation for all hardware rehabilitation pathways. Three management rehabilitation pathways were identified. All require the involvement of community leaders and were best carried out when the action was participatory.

Conclusions

The rehabilitation pathways show how available resources can be leveraged to restore hardware breakdowns and management failures for rural water systems in sub-Saharan Africa. Governments, NGOs, and private sector actors can better build capacity of community actors by focusing on their role in rehabilitating hardware and management and to ensure that they are able to quickly contact external support actors when needed for rehabilitation. Using qualitative and participatory methods allows for insight into rapid rehabilitation of hardware and management.  相似文献   
907.
908.
909.
910.
The inter- and intrapersonal variability in the absorption and disposition of erythromycin estolate in humans was assessed by comparing total erythromycin serum concentrations in five subjects who each received a single erythromycin estolate tablet on three separate occasions under identical experimental conditions. Coefficients of variation for the pharmacokinetic parameters Cmax, Tmax, AUC0-12, MRT, and t1/2 were of a similar magnitude when calculated between subjects in any one administration phase or between phases. In addition, serum concentrations of both erythromycin base (active component) and erythromycin propionate were selectively determined in the same subjects only during the final two phases of the study. Comparison of AUC0-12 values showed that the percentage of the total area (base and ester components) present as erythromycin base remained relatively constant between administrations (mean values of 14.5 and 11.2%), with low coefficients of variation between subjects (10.8 and 11.6%). Discrepancy value calculations revealed that the variability in serum concentration-time profiles between the three phases of the study fell into the "small"-to-"moderate" classification. From these data it is apparent that intrapersonal variations in the absorption and disposition of erythromycin estolate are of a similar magnitude to interpersonal variations and should be borne in mind in the design and interpretation of comparative bioavailability studies involving similar formulations of this compound. The relative proportions of erythromycin base and propionate did, however, remain fairly constant both between treatments and between subjects.  相似文献   
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