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51.
52.
Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.  相似文献   
53.
Our aim was to analyze the existing body of evidence about inpatient care of patients suffering from rheumatoid arthritis (RA). The report was induced by the executive board of the German Society of Rheumatology which assigned the "Oliver-Sangha committee" to dissect and point out the tasks of inpatient care during the next few years. A systemic search of the literature was performed covering the years 1966 to 2001. A total of 16 studies were selected and thoroughly appraised in a systematic way. Four randomized controlled trials addressing the question could be identified. All of them included only patients in a clinical condition allowing outpatient care as well. Two studies indicate some advantage of inpatient care in comparison to outpatient treatment. Two studies, both equivalence studies from design, reveal that RA patients do not generally experience additional benefit from hospitalization. Consideration of two additional cohort studies demonstrates the increased need of inpatient care in RA patients. None of the studies was derived from the German health care system. Emergency cases were not the subject of any of these trials. General statements about the value of inpatient care of RA patients can not be drawn from the analyzed studies. The committee makes suggestions for future investigations that may help to answer this important question considering the special circumstances of the German health care system.  相似文献   
54.
Polyploidy is a prominent process in plant evolution; yet few data address the question of whether homeologous sequences evolve independently subsequent to polyploidization. We report on ribosomal DNA (rDNA) evolution in five allopolyploid (AD genome) species of cotton (Gossypium) and species representing their diploid progenitors (A genome, D genome). Sequence data from the internal transcribed spacer regions (ITS1 and ITS2) and the 5.8S gene indicate that rDNA arrays are homogeneous, or nearly so, in all diploids and allopolyploids examined. Because these arrays occur at four chromosomal loci in allopolyploid cotton, two in each subgenome, repeats from different arrays must have become homogenized by interlocus concerted evolution. Southern hybridization analysis combined with copy-number estimation demonstrate that this process has gone to completion in the diploids and to completion or near-completion in all allopolyploid species and that it most likely involves the entire rDNA repeat. Phylogenetic analysis demonstrates that interlocus concerted evolution has been bidirectional in allopolyploid species--i.e., rDNA from four polyploid lineages has been homogenized to a D genome repeat type, whereas sequences from Gossypium mustelinum have concerted to an A genome repeat type. Although little is known regarding the functional significance of interlocus concerted evolution of homeologous sequences, this study demonstrates that the process occurs for tandemly repeated sequences in diploid and polyploid plants. That interlocus concerted evolution can occur bidirectionally subsequent to hybidization and polyploidization has significant implications for phylogeny reconstruction, especially when based on rDNA sequences.  相似文献   
55.
目的 分析MRI形态学半定量评分对新生儿细菌性脑膜炎出院结局的评估价值。方法 收集复旦大学附属儿科医院2011年7月至2013年12月NICU收治的出院诊断为新生儿细菌性脑膜炎的病例,采用基于大脑损伤MRI形态学分析的半定量评分,对头颅MRI图像进行回顾性分析。MRI形态学评价包括脑室扩大、脑室旁白质容积丢失、脑白质囊性病灶、内囊后肢髓鞘化异常、皮质信号异常、颅内脑外间隙异常、基底节信号异常、脑白质非囊性信号异常、脑室内出血、脑室积脓、脑膜异常强化、室管膜异常强化和脑脓肿。将上述13项评分归纳为脑白质异常(WMA)、脑灰质异常(GMA)和非脑实质异常(NPA)。同时采集患儿出生孕周、发病时间、MRI检查时间、发病至MRI检查间隔时间和出院结局。按照出生孕周分为早产儿组和足月儿组,再按照出院结局分为预后良好和预后不良亚组,在各组内比较亚组之间时间因素、MRI单项评分和综合评分的差异。结果 63例新生儿细菌性脑膜炎病例进入分析(早产儿组18例,足月儿组45例)。MRI单项评分构成预后良好和预后不良亚组间差异有统计学意义的指标:早产儿组中有脑室扩大(P=0.012)和脑室旁白质容积丢失(P=0.004);足月儿组有脑室扩大(P=0.002)、脑室旁容积丢失(P=0.040)、颅内脑外间隙异常(P=0.005)和脑室内出血(P=0.038)。MRI综合评分中,早产儿组WMA评分(P=0.001)和NPA评分(P=0.039)、足月儿组NPA评分(P=0.018)在预后不良和预后良好亚组之间分布差异有统计学意义。足月儿组和早产儿组内不同预后亚组的各时间因素差异未发现统计学意义或临床意义。结论 新生儿细菌性脑膜炎MRI脑室扩大和脑室旁白质容积丢失预示早产儿出院不良结局;脑室扩大、脑室旁白质容积丢失、颅内脑外间隙异常和脑室内出血预示足月儿出院不良结局。WMA评分高预示早产儿出院不良结局,NPA评分高预示早产儿和足月儿出院不良结局。  相似文献   
56.
57.

Objective

The objective of this study was to determine specific provider practices associated with high provider efficiency in community emergency departments (EDs).

Methods

A mixed‐methods study design was utilized to identify key behaviors associated with efficiency. Stage 1 was a convenience sample of 16 participants (ED medical directors, nurses, advanced practice providers, and physicians) identified provider efficiency behaviors during semistructured interviews. Ninety‐nine behaviors were identified and distilled by a group of three ED clinicians into 18 themes. Stage 2 was an observational study of 35 providers was performed in four (30,000‐ to 55,000‐visit) community EDs during two 4‐hour periods and recorded in minute‐by‐minute observation logs. In Stage 3, each behavior or practice from Stage 1 was assigned a score within each observation period. Behaviors were tested for association with provider efficiency (relative value units/hour) using linear univariate generalized estimating equations with an identity link, clustered on ED site.

Results

Five ED provider practices were found to be positively associated with efficiency: average patient load, using name of team member, conversations with health care team, visits to patient rooms, and running the board. Two behaviors, “inefficiency practices,” demonstrated significant negative correlations: non–work‐related tasks and documentation on patients no longer in the ED.

Conclusions

Average patient load, running the board, conversations with team member, and using names of team members are associated with enhanced provider productivity. Identification of behaviors associated with efficiency can be utilized by medical directors, clinicians, and trainees to improve personal efficiency or counsel team members.
  相似文献   
58.
59.
Cassileth  PA; Suholet  D; Cooper  RA 《Blood》1981,58(2):237-243
The HL-60 leukemia cell line derived from a human acute promyelocytic leukemia is stimulated to differentiate into macrophages within 24-28 hr after exposure to the phorbol ester, 12-O-tetradecanoylphorbol-13- acetate (TPA). We studied early alterations (within 90 min of exposure to TPA) in phosphatidylcholine metabolism in HL-60 cells and found that phosphatidylcholine synthesis by methylation is phosphatidylethanolamine was inhibited in a dose-dependent fashion. In contrast, synthesis of phosphatidylcholine from endogenous choline was enhanced and correlated inversely with the degree of inhibition of the methylation pathway. Phorbol ester congeners of TPA caused similar alterations in phosphatidylcholine metabolism in direct relationship to their capacity to induce differentiation in HL-60 cells. Perturbation of phosphatidylcholine metabolism is an early membrane even in TPA- induced HL-60 cell differentiation.  相似文献   
60.
We recently reported a significant increase in the frequency of carriers of grey zone (GZ) alleles of FMR1 gene in Australian males with Parkinson's disease (PD) from Victoria and Tasmania. Here, we report data comparing an independent sample of 817 PD patients from Queensland to 1078 consecutive Australian male newborns from Victoria. We confirmed the earlier finding by observing a significant excess of GZ alleles in PD (4.8%) compared to controls (1.5%). Although both studies provided evidence in support of an association between GZ‐carrier status and increased risk for parkinsonism, the existing evidence in the literature from screening studies remains equivocal and we discuss the need for alternative approaches to resolve the issue.  相似文献   
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