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41.
BACKGROUND: Emergency admission rates have been rising steadily in recent years, with the majority of the increase owing to emergency medical admissions. Possible causative factors include changing demography, incidence of disease, admission thresholds, multiple admissions, and appropriateness of admission. AIM: To investigate the impact of patient and practice factors on variance in general practices' emergency medical admissions rates. DESIGN OF STUDY: Multiple regression analysis relating emergency medical admission rates of general practices to patient and practice characteristics. SETTING: The study was conducted between 1996 and 1997 in the acute hospital trust serving the study area, Dundee, Scotland. METHOD: Scottish Morbidity Record 1 (SMR1) data, which contains details of all hospital consultant episodes, was used to calculate individual practices emergency medical admission rates. These rates were then standardised to an expected value of 100. Forward selection was used to find a suitable multiple regression model to predict each practice's emergency medical admission rate from practice and patient variables. RESULTS: Crude emergency medical admission rates for general practices showed a 1.8-fold variation between the top and bottom deciles. The deprivation status and age of patients explained 42% of the variance in admission rates (64% with the exclusion of one practice that had a poor fit to the model). After correcting for age and deprivation there was a 1.2-fold variation in general practices' emergency medical admission rates. CONCLUSION: The most important factors in explaining variance in general practices' emergency medical admission rates are socio-demographic, with age and deprivation explaining a large proportion of the variation. We found no evidence to support the contention that general practice factors were linked with admission rates.  相似文献   
42.
This study examined sociodemographic, behavioral and psychosocial factors associated with BMI, weight perceptions and trying to lose weight among African-American smokers (N=600, M=44.2 years, 70% female). Sixty-eight percent of the sample were overweight or obese (sample BMI M=28.0, SD=6.7). Three separate, simultaneous multivariable regression models were used to determine which factors were associated with BMI, weight perceptions and trying to lose weight. Poorer health, female gender and high-school education or higher were significantly associated with higher BMIs (p<0.05). Being female (OR=5.8, 95% CI=3.6-9.3) and having a higher BMI (OR=0.6, 95% CI=0.5-0.6) was associated with perception of overweight and smoking more cigarettes per day (OR=1.0, 95% CI=1.0-1.1), and perceiving oneself as overweight (OR=14.1, 95% CI=8.2-24.2) was associated with trying to lose weight. Participants somewhat underestimated their BMI in their weight perceptions. Those who perceived themselves as overweight were more likely to be trying to lose weight; therefore, increasing participant awareness of actual BMI status may lead to improved weight-control efforts in African-American smokers. Several expected associations with outcomes were not found, suggesting that BMI and weight constructs are not well-understood in this population.  相似文献   
43.
In vitro degradation of silk fibroin   总被引:14,自引:0,他引:14  
A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy. Control samples were incubated in phosphate-buffered saline. Fibroin was shown to proteolytically degrade with predictable rates of change in fibroin diameter, failure strength, cycles to failure, and mass. SEM indicated increasing fragmentation of individual fibroin filaments from protease-digested samples with time of exposure to the enzyme; particulate debris was present within 7 days of incubation. Gel electrophoresis indicated a decreasing amount of the silk 25 kDa light chain and a shift in the molecular weight of the heavy chain with increasing incubation time in protease. Results support that silk is a mechanically robust biomaterial with predictable long-term degradation characteristics.  相似文献   
44.
CPEB is an mRNA-binding protein that stimulates polyadenylation-induced translation of maternal mRNA once it is phosphorylated on Ser 174 or Thr 171 (species-dependent). Disruption of the CPEB gene in mice causes an arrest of oogenesis at embryonic day 16.5 (E16.5), when most oocytes are in pachytene of prophase I. Here, we show that CPEB undergoes Thr 171 phosphorylation at E16.5, but dephosphorylation at the E18.5, when most oocytes are entering diplotene. Although phosphorylation is mediated by the kinase aurora, the dephosphorylation is due to the phosphatase PP1. The temporal control of CPEB phosphorylation suggests a mechanism in which CPE-containing mRNA translation is stimulated at pachytene and metaphase I.  相似文献   
45.
Fiber optic probes are a key element for biomedical spectroscopic sensing. We review the use of fiber optic probes for optical spectroscopy, focusing on applications in turbid media, such as tissue. The design of probes for reflectance, polarized reflectance, fluorescence, and Raman spectroscopy is illustrated. We cover universal design principles as well as technologies for beam deflecting and reshaping.  相似文献   
46.
To the best of our knowledge, there are no published data on the historical and recent use of CGM in clinical trials of pharmacological agents used in the treatment of diabetes. We analyzed 2,032 clinical trials of 40 antihyperglycemic therapies currently on the market with a study start date between 1 January 2000 and 31 December 2019. According to ClinicalTrials.gov, 119 (5.9%) of these trials used CGM. CGM usage in clinical trials has increased over time, rising from <5% before 2005 to 12.5% in 2019. However, it is still low given its inclusion in the American Diabetes Association’s latest guidelines and known limitations of A1C for assessing ongoing diabetes care.

The availability of reliable continuous glucose monitoring (CGM) systems has proven to be a major innovation in diabetes management and research. Most current CGM systems are approved for 7- to 14-day use and use a wire-tipped glucose oxidase sensor inserted in subcutaneous tissue to monitor glucose concentrations in interstitial fluid. One implanted CGM system is approved for longer-term use (90–180 days); it operates with fluorescence-based technology. CGM sensors record a glucose data point every 1–15 minutes (depending on the system), collecting far more granular data and information on glycemic patterns than self-monitoring of blood glucose (SMBG) alone. Real-time CGM or intermittently scanned CGM systems send data continuously or intermittently to dedicated receivers or smartphones, whereas professional CGM systems provide retrospective data, either blinded or unblinded, for analysis and can be used to identify patterns of hypo- and hyperglycemia. Professional CGM can be helpful to evaluate patients when other CGM systems are not available to the patient or the patient prefers a blinded analysis or a shorter experience with unblinded data.In the 20 years since CGM systems first became available to people with diabetes, technological improvements, particularly pertaining to accuracy and form factor, have made CGM increasingly viable for both patient use and clinical investigation (1,2). Average sensor MARD (mean absolute relative difference; a summary accuracy statistic) has decreased from >20 to <10% (310), including two systems that do not require fingerstick calibrations and three that are approved to be used for insulin dosing (11). Concurrently, size, weight, and cost of CGM systems have all decreased, while user-friendliness and convenience have increased (12).To encourage use of CGM-derived data, researchers and clinicians have worked to develop a standard set of glycemic metrics beyond A1C. In 2017, two international groups of leading diabetes clinical and research organizations published consensus definitions for key metrics, including clinically relevant glycemic cut points for hypoglycemia (<70 and <54 mg/dL), hyperglycemia (>180 and >250 mg/dL), and time in range (TIR; 70–180 mg/dL) (13,14).CGM-derived metrics provide far greater precision and granularity than is possible with SMBG or A1C data alone (Table 1), enabling clinicians and investigators to better represent inter- and intraday glycemic differences with metrics such as TIR, glycemic variability, and time in hypoglycemia and hyperglycemia (15). Crucially, CGM also allows for the accurate measurement and detection of nocturnal glycemia (16). The use of these metrics enables a more comprehensive understanding of glycemic management that can facilitate individualized treatment for people with diabetes or prediabetes. Although A1C is a useful estimate of mean glucose over the previous 2–3 months, especially when evaluating population health, it is important to include other glycemic outcomes in clinical trials. Furthermore, there is emerging evidence suggesting that TIR predicts the development of microvascular complications at least as well as A1C (17,18).TABLE 1Benefits of CGM Compared With A1C Alone in Assessing Glycemia
CGMA1C Alone
Facilitates real-time readings of blood glucose levelsRequires SMBG
Provides information on glucose variability, including duration of hypo- and hyperglycemia and nocturnal glycemiaDoes not provide information on acute glycemic excursions and time in biochemical hypoglycemia and hyperglycemia
Correlates strongly with 3 months of mean glucose, TIR, and hyperglycemia metricsMeasures average glucose during the past 2–3 months
Provides information on direction of and rate of change in glucose levelsDoes not provide information on direction of or rate of change in glucose levels
Provides TIR data (time spent between 70 and 180 mg/dL)Does not have TIR measurement capability
Open in a separate windowDespite recent standardization of metrics and an emerging consensus around the importance of including CGM-derived outcomes in clinical trials, to our knowledge, there has been no attempt to estimate the historical and current use of CGM in clinical trials of pharmacological agents for diabetes. We sought to analyze the use of CGM in trials of currently available pharmaceutical agents for the treatment of diabetes.  相似文献   
47.
Beta-mannosidosis is an autosomal recessive lysosomal storage disease resulting from a deficiency of the lysosomal enzyme beta-mannosidase. The clinical manifestations of this disease in reported human cases are very heterogeneous ranging from relatively mild to moderately severe. This is in contrast with the severe prenatal onset seen in ruminant beta-mannosidosis. In humans, mental retardation, hearing loss, frequent infections, and behavioral problems are relatively common. Dysmorphology and skeletal involvement such as those seen in ruminants are unusual. The purpose of this study is to determine the range of clinical expression in human beta-mannosidosis resulting from null mutations. We determined that the beta-mannosidase gene consists of 17 exons. Intron-based PCR primers were designed and used to amplify each of the exons in genomic DNA isolated from patient fibroblasts. We identified two patients with null mutations. Results of the analysis showed that one patient was heterozygous for nonsense mutations G334T (E83X) in exon 2 and C1363T (Q426X) in exon 10, resulting in truncation of the deduced peptide sequence from 879 to 82 and 425 amino acids, respectively. The second patient was homozygous for a deletion mutation in exon 11 (1541delAT). This deletion causes a reading frame shift and 26 out of frame amino acids before a stop codon occurs in exon 12, resulting in truncation of the deduced peptide sequence from 879 to 510 amino acids. Because disease presentation in these patients with null mutations is very variable, ranging from mild to severe, we conclude that beta-mannosidosis in humans may indeed be milder than typical of other lysosomal storage disorders.  相似文献   
48.
We analyzed Burkholderia cepacia complex isolates recovered from 1,218 cystic fibrosis (CF) patients and 90 patients without CF. Although all B. cepacia complex species were found, some were rarely identified. The distribution of species differed between the CF and non-CF populations and appears to be changing over time among CF patients.  相似文献   
49.
Virtually all clinical isolates of group A streptococci secrete a highly conserved extracellular cysteine protease that cleaves human fibronectin and vitronectin, and converts IL-1β precursor to biologically active IL-1β. Based on the high degree of gene conservation within the species and its role in host pathogenicity, it was postulated that antibodies to the cysteine protease would confer protective immunity against S. pyogenes infection. To test this hypothesis, Swiss CD1 mice were intraperitoneally administered either saline, rabbit IgG, or IgG from rabbits immunized with the protease, and challenged with a highly virulent (minimum lethal dose 10 cfu) clinical isolate of S. pyogenes expressing a heterologous cysteine protease. The results indicate that mice administered IgG from rabbits immunized with purified cysteine protease had significantly enhanced survival when compared with mice given either non-specific rabbit IgG (log rank test; χ2; p = 0.0195) or saline (log rank test; χ2; p = 0.0002). Moreover, mice actively immunized with the cysteine protease had a significantly longer time to death than the control group (log rank test; χ2; p = 0.0418). The results show that the cysteine protease elicits non-type-specific immunity to challenge with heterologous S. pyogenes.  相似文献   
50.
Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies. We assessed the relative frequency of all 30 leukodystrophies (associated with 55 genes) in more than 49,000 exomes. We identified a relatively high frequency of disorders previously thought of as very rare, including Aicardi Goutières Syndrome, TUBB4A‐related leukodystrophy, Peroxisomal biogenesis disorders, POLR3‐related Leukodystrophy, Vanishing White Matter, and Pelizaeus‐Merzbacher Disease. Despite the relative frequency of these conditions, carrier‐screening laboratories regularly test only 20 of the 55 leukodystrophy‐related genes, and do not test at all, or test only one or a few, genes for some of the higher frequency disorders. Relative frequency of leukodystrophies previously considered very rare suggests these disorders may benefit from expanded carrier screening.  相似文献   
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