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Changes in physical body size during gestation were monitored using 529 sets of sow measurements. All sows were from the same herd and production system with a range in parity from 1 to 8. Sows were individually weighed, P2 backfat thickness was determined by ultrasound and morphometric measurements of body size were taken five times during gestation: day 0 (at service), day 25, day 50, day 80 and day 110. The morphometric measurements included sow height (from floor to last rib at the midline, from floor to ventral surface and from floor to hip), heart girth, depth of last rib, length (from snout to tail and from anterior scapula to tail) and width (at ham, at last rib and at shoulder). Regression analyses were used to model the relationship between day of gestation or parity number and morphometric measurements of body size. Regression equations were also developed to estimate sow weight from physical measurements, day of gestation and parity. As expected, sow dimensions, in general, increased as pregnancy progressed and also with increasing parity number. The relationships between day of gestation and body dimensions were described by linear and quadratic regression models, which had a range of adjusted R2 values up to 0.99. Similar relationships to parity number had a range of R2 values between 0.51 and 0.96. Sow depth, which can be used as an estimate of the width of the sow when lying, equalled the maximum width of the gestation stall (650 mm) at day 103 of gestation. However, by day 40 of gestation, predicted mean sow depth (570 mm) equalled the width at the rear of the crate. The implication of this is that after day 40 of gestation, the average sow was too wide for the rear of the crate when lying in a recumbent position. On day 110 of gestation, 95% of the mean sow body depths would be accommodated in stalls that were 674 mm wide; however, the range in body sizes with increasing parity number suggests the use of more than one stall width would be appropriate. Sow weight could be estimated with an adjusted R2 value of 0.81 and with a residual standard deviation (r.s.d.) of 16.5 kg using heart girth alone, or more accurately using a model with parity, day of gestation, P2 backfat depth and heart girth as the parameters (R2 = 0.89, r.s.d. 12.4 kg).  相似文献   
13.
We isolated 20 anonymous nuclear loci (8556 bp in total) from the Taiwan Hwamei (Garrulax taewanus), an endemic songbird of Taiwan. A panel of nine to 15 individuals with unknown relationship was used to characterize polymorphism of these loci. We identified 46 single nucleotide polymorphic sites (SNPs) in 15 polymorphic loci. Frequency of SNPs was one per every 186 bp in average. Nucleotide diversity, θ, ranged from 0.00054 to 0.00371 per locus. We also tested cross‐species applicability of these loci on 17 species from eight different passerine families. All 20 loci could be successfully amplified (ranged from one to 16 species, mean = 7.9 species).  相似文献   
14.
Glucagon-like peptide-1(7-36)amide (tGLP-1) is inactivated by dipeptidyl peptidase (DPP) IV by removal of the NH(2)-terminal dipeptide His(7)-Ala(8). We examined the degradation of NH(2)-terminally modified His(7)99% of His(7)-glucitol tGLP-1 remained intact at 12 h. His(7)-glucitol tGLP-1 was similarly resistant to plasma degradation in vitro. His(7)-glucitol tGLP-1 showed greater resistance to degradation in vivo (92% intact) compared to tGLP-1 (27% intact) 10 min after i.p. administration to Wistar rats. Glucose homeostasis was examined following i.p. injection of both peptides (12 nmol/kg) together with glucose (18 mmol/kg). Plasma glucose concentrations were significantly reduced and insulin concentrations elevated following peptides administration compared with glucose alone. The area under the curve (AUC) for glucose for controls (AUC 691+/-35 mM/min) was significantly lower after administration of tGLP-1 and His(7)-glucitol tGLP-1 (36 and 49% less; AUC 440+/-40 and 353+/-31 mM/min, respectively; P<0.01). This was associated with a significantly higher AUC for insulin (98-99% greater; AUC 834+/-46 and 838+/-39 ng/ml/min, respectively; P<0.01) after tGLP-1 and His(7)-glucitol tGLP-1 administration compared to controls (421+/-30 ng/ml/min). In conclusion, His(7)-glucitol tGLP-1 resists plasma DPP IV degradation while retaining potent antihyperglycaemic and insulin-releasing activities in vivo.  相似文献   
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16.

Background

Accurately predicting the probability of a live birth after in vitro fertilisation (IVF) is important for patients, healthcare providers and policy makers. Two prediction models (Templeton and IVFpredict) have been previously developed from UK data and are widely used internationally. The more recent of these, IVFpredict, was shown to have greater predictive power in the development dataset. The aim of this study was external validation of the two models and comparison of their predictive ability.

Methods and Findings

130,960 IVF cycles undertaken in the UK in 2008–2010 were used to validate and compare the Templeton and IVFpredict models. Discriminatory power was calculated using the area under the receiver-operator curve and calibration assessed using a calibration plot and Hosmer-Lemeshow statistic. The scaled modified Brier score, with measures of reliability and resolution, were calculated to assess overall accuracy. Both models were compared after updating for current live birth rates to ensure that the average observed and predicted live birth rates were equal. The discriminative power of both methods was comparable: the area under the receiver-operator curve was 0.628 (95% confidence interval (CI): 0.625–0.631) for IVFpredict and 0.616 (95% CI: 0.613–0.620) for the Templeton model. IVFpredict had markedly better calibration and higher diagnostic accuracy, with calibration plot intercept of 0.040 (95% CI: 0.017–0.063) and slope of 0.932 (95% CI: 0.839–1.025) compared with 0.080 (95% CI: 0.044–0.117) and 1.419 (95% CI: 1.149–1.690) for the Templeton model. Both models underestimated the live birth rate, but this was particularly marked in the Templeton model. Updating the models to reflect improvements in live birth rates since the models were developed enhanced their performance, but IVFpredict remained superior.

Conclusion

External validation in a large population cohort confirms IVFpredict has superior discrimination and calibration for informing patients, clinicians and healthcare policy makers of the probability of live birth following IVF.  相似文献   
17.

Introduction

Emergency departments see an increase in cases during cyclones. The aim of this study is to describe patient presentations to the Emergency Department (ED) of a tertiary level hospital (Townsville) following a tropical cyclone (Yasi). Specific areas of focus include changes in: patient demographics (age and gender), triage categories, and classification of diseases.

Methods

Data were extracted from the Townsville Hospitals ED information system (EDIS) for three periods in 2009, 2010 and 2011 to coincide with formation of Cyclone Yasi (31 January 2011) to six days after Yasi crossed the coast line (8 February 2012). The analysis explored the changes in ICD10-AM 4-character classification and presented at the Chapter level.

Results

There was a marked increase in the number of patients attending the ED during Yasi, particularly those aged over 65 years with a maximum daily attendance of 372 patients on 4 Feb 2011. The most marked increases were in: Triage categories - 4 and 5; and ICD categories - diseases of the skin and subcutaneous tissue (L00-L99), and factors influencing health care status (Z00-Z99). The most common diagnostic presentation across all years was injury (S00-T98).

Discussion

There was an increase in presentations to the ED of TTH, which peaked in the first 24 – 48 hours following the cyclone and returned to normal over a five-day period. The changes in presentations were mostly an amplification of normal attendance patterns with some altered areas of activity. Injury patterns are similar to overseas experience.  相似文献   
18.

Background

Previous studies have reported an inverse association between vitamin D and childhood dental caries, but whether this is causal is unclear.

Objective

To determine the causal effect of circulating 25-hydroxyvitamin D concentration on dental caries experience, early caries onset and the requirement for a dental general anesthetic.

Design

A Mendelian randomization study was undertaken, using genetic variants known to be associated with circulating 25-hydroxyvitamin D concentrations in 5,545 European origin children from the South West of England. Data on caries and related characteristics were obtained from parental and child completed questionnaires between 38 and 91 months and clinical assessments in a random 10% sample at 31, 44 and 61 months.

Results

In multivariable confounder adjusted analyses no strong evidence for an association of 25-hydroxyvitamin D with caries experience or severity was found but there was evidence for an association with early caries onset, or having a general anesthetic for dental problems. In Mendelian randomization analysis the odds ratio for caries experience per 10 nmol/L increase in 25-hydroxyvitamin D was 0.93 (95% confidence interval: 0.83, 1.05; P = 0.26) and the odds ratio for dental general anaesthetic per 10 nmol/L increase in 25-hydroxyvitamin D was 0.96 (95% confidence interval: 0.75, 1.22; P = 0.72).

Conclusions

This Mendelian randomization study provides little evidence to support an inverse causal effect of 25-hydroxyvitamin D on dental caries. However, the estimates are imprecise and a larger study is required to refine these analyses.  相似文献   
19.
Microsporidiosis poses a problem for immunocompromised individuals including patients with HIV infection as well as those with organ transplantation. Recent reports from Africa have suggested that microsporidiosis with diarrhea is an independent risk factor for malnutrition in children. Previous studies from our laboratory have demonstrated that CD8+ T cells are an essential component of protective immunity against the microsporidium Encephalitozoon cuniculi. Mutant mice lacking this T cell subset or cytotoxic function are unable to clear the infection and ultimately succumb to the disease. However, information regarding the antigens involved in the elicitation of CD8+ T cell response is not available. In this study, we report that immunization of animals with Encephalitozoon hellem polar tube protein 1 (rEhPTP1) induces a strong T cell response in vaccinated animals. Splenic dendritic cells pulsed with rEhPTP1 are able to induce E. cuniculi specific CD8+ T cell response with no effect on the CD4+ T cell subset. This is the first report identifying a protein capable of inducing CD8+ T cell immunity, which is conserved in other microsporidial species of human importance.  相似文献   
20.
Salmonella spp. infection is a major cause of gastroenteritis, with many thousands of cases reported in the European Union every year. The use of probiotics offers the potential to improve this situation. Here, we investigate the effects of oral treatment of pigs with a defined lactic acid bacteria culture mixture on both clinical and microbiological signs of Salmonella enterica serovar Typhimurium infection. Fifteen weaned pigs blocked by sex and weight were administered control milk or a mixture of five probiotic strains as either a milk fermentate or milk suspension for a total of 30 days. The mixture consisted of two strains of Lactobacillus murinus and one strain each of Lactobacillus salivarius subsp. salivarius, Lactobacillus pentosus, and Pediococcus pentosaceous. Following probiotic administration for 6 days, animals were challenged orally with serovar Typhimurium; the health of the animals and the microbiological composition of their feces were monitored for 23 days postinfection. Animals treated with probiotic showed reduced incidence, severity, and duration of diarrhea. These animals also gained weight at a greater rate than control pigs administered skim milk. Mean fecal numbers of Salmonella were significantly reduced in probiotic-treated animals at 15 days postinfection (P = 0.01). The administered probiotic bacteria improved both the clinical and microbiological outcome of Salmonella infection. These strains offer significant benefit for use in the food industry and may have potential in human applications.  相似文献   
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