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71.
A study has shown that staff do not generally perceive challenging behaviour in people with profound intellectual and multiple disabilities (PIMD) as being of serious consequence. In this study we aimed to gain a better understanding of the causal explanations that direct care and support staff give for challenging behaviour in this group. The purpose of this study was twofold: (1) to determine the way staff attribute challenging behaviour in children and adults with PIMD; and (2) to analyse whether more experienced staff attribute challenging behaviour in children and adults with PIMD differently than less experienced staff. In total, 195 direct support staff and an equal number of children and adults with PIMD participated in the study. Direct support staff filled out the Challenging behaviour Attribution Scale (five causal explanatory models of challenging behaviour) to explain challenging behaviour in one individual that they supported. The results show that direct support staff as a whole report the biomedical model as the most plausible explanation for challenging behaviour in children and adults with PIMD. However, in the present study the mean scores on all models are low. This might indicate that a large number of staff found none of the models particularly useful as possible explanations of challenging behaviour in people with PIMD. This could mean that staff have difficulties stating the cause of challenging behaviour in this group. Another possible explanation could be that there is little scientific knowledge about causing and maintaining factors of challenging behaviour in people with PIMD. It could also mean that staff have additional explanations for challenging behaviour in this target group that are not mentioned in the instrument used. Future research should address these issues. No differences were found between more experienced and less experienced direct support staff.  相似文献   
72.
目的 评价MR相位速度图检测椎动脉血流动力学的价值及其诊断椎动脉狭窄的准确性。材料与方法 测量32列患者的椎动脉直径、流速及最大返流速度并与经颅多普勒超声(TCD)进行比较,通过t检验判断椎动脉狭窄患者与对照组之间有无差异以及x^2检验评判MR相位速度图测量椎动脉狭窄的准确性和特异性。结果 MR相位速度图与TCDF的检测结果具有一致性(x^2=0.5,P〉0.05);20例椎动脉狭窄患者的椎动脉流  相似文献   
73.
This study investigated the attitudes and beliefs of pig farmers and hunters in Germany, Bulgaria and the western part of the Russian Federation towards reporting suspected cases of African swine fever (ASF). Data were collected using a web‐based questionnaire survey targeting pig farmers and hunters in these three study areas. Separate multivariable logistic regression models identified key variables associated with each of the three binary outcome variables whether or not farmers would immediately report suspected cases of ASF, whether or not hunters would submit samples from hunted wild boar for diagnostic testing and whether or not hunters would report wild boar carcasses. The results showed that farmers who would not immediately report suspected cases of ASF are more likely to believe that their reputation in the local community would be adversely affected if they were to report it, that they can control the outbreak themselves without the involvement of veterinary services and that laboratory confirmation would take too long. The modelling also indicated that hunters who did not usually submit samples of their harvested wild boar for ASF diagnosis, and hunters who did not report wild boar carcasses are more likely to justify their behaviour through a lack of awareness of the possibility of reporting. These findings emphasize the need to develop more effective communication strategies targeted at pig farmers and hunters about the disease, its epidemiology, consequences and control methods, to increase the likelihood of early reporting, especially in the Russian Federation where the virus circulates.  相似文献   
74.
Summary

Maize seeds of the single cross WF 9 × 38?11 were irradiated with pile neutrons with doses ranging from 1 × 1012 Np to 5 × 1014 Np and then treated with gibberellic acid (GA). In one set of experiments the seeds were soaked in GA for 24 hours and raised in sand. In another set they were sprouted in water, and seedlings with a 2–3 cm root-length were from then grown on in GA solution. It was evident from both these experiments that GA can reverse the stunting of seedlings caused by radiation.  相似文献   
75.

Objective

The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations.

Methods

A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output.

Results

There was a high linear correlation between MPA-PC flow and RV–stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and –2.3 mL for RV–short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis–LV SV and short-axis–RV SV.

Conclusion

No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes.  相似文献   
76.
Reliability of magnetic resonance (MR) velocity mapping to assess severity of stenosis was assessed in vitro. Steady flow at different flow rates through five stenoses with a central orifice area ranging from 17 to 176 mm2 was measured with velocity mapping performed perpendicular to the stenotic jet. Besides determination of the stenotic cross-sectional area and flow rate, the pressure gradient was calculated with the modified Bernoulli equation and compared with manometer measurements. Cross-sectional areas were measured with an accuracy of ?76%, a precision of ?91%, and an error of ?19 mm2. Flow rates had an accuracy of ?72%, a precision of ?94%, and an error of ?1.4 L/min. The modification of the Bernoulli equation limited its reliability to stenoses with areas of 35-113 mm2. Pressure gradients were calculated with an accuracy of ?80%, a precision of ?88%, and an error of ?15 mm Hg. The method was applied in a single patient with aortic stenosis and gave estimates that agreed with those obtained by heart catheterization.  相似文献   
77.
In the postoperative patient with anginal symptoms, differentiation between bypass graft compromise and nonischemic causes has until now been accomplished only by means of x-ray angiography. A noninvasive test is clearly desirable. The authors used a cine phase-contrast (PC) magnetic resonance (MR) imaging technique to characterize blood flow in native and grafted internal mammary arteries (IMAs). Ten volunteers and 15 patients who had recently undergone IMA coronary artery bypass grafting were imaged. Cine PC MR imaging was performed in the transaxial plane at the level of the pulmonary artery bifurcation. Flow in both IMAs was quantified and expressed as a percentage of cardiac output measured in the ascending aorta. In the 15 patients, flow analysis was performed in both the native and grafted IMAs. In the volunteers, IMA blood flow ranged from 2.1% to 4.3% of cardiac output on the left (mean, 3.5%) and 2.1% to 5.1% (mean, 3.5%) on the right. There was considerable intersubject variability, with coefficients of variation of 10.7% for the left and 12.3% for the right IMA. Intrasubject variability was limited, with estimated common standard deviations of 0.45% of cardiac output (range, 0.2%–1.1%) for the left and 0.39% (range, 0.1%–0.6%) for the right IMA. Flow in grafted IMAs was identified in 13 of 15 patients. In one of two patients without demonstrable IMA graft flow, cardiac catheterization confirmed lack of flow. IMA graft flow varied from 28 to 164 mL/min (mean, 80.3 mL/min). This study shows the feasibility of using cine PC MR imaging as a quantitative method of evaluating blood flow in IMA coronary artery bypass grafts.  相似文献   
78.
Background We studied the maximum tolerated dose (MTD) and efficacy of oxaliplatin added to capecitabine and radiotherapy (Capox-RT) as neoadjuvant therapy for rectal cancer. Methods T3-4 rectal cancer patients received escalating doses of oxaliplatin (day 1 and 29) with a fixed dose of capecitabine of 1000 mg/m2 twice daily (days 1–14, 25–38) added to RT with 50.4 Gy and surgery after 6–8 weeks. The MTD, determined during phase I, was used in the subsequent phase II, in which R0 resection rate (a negative circumferential resection margin) was the primary end point. Results Twenty-one patients were evaluable. In the phase I part, oxaliplatin at 85 mg/m2 was established as MTD. In phase II, the main toxicity was grade III diarrhea (18%). All patients underwent surgery, and 20 patients had a resectable tumor. An R0 was achieved in 17/21 patients, downstaging to T0-2 in 7/21 and a pCR in 2/21. Conclusion Combination of Capox-RT has an acceptable acute toxicity profile and a high R0 resection rate of 81% in locally advanced rectal cancer. However the pCR rate was low.  相似文献   
79.

Introduction

Concurrent partnerships (CPs) have been suggested as a risk factor for transmitting HIV, but their impact on the epidemic depends upon how prevalent they are in populations, the average number of CPs an individual has and the length of time they overlap. However, estimates of prevalence of CPs in Southern Africa vary widely, and the duration of overlap in these relationships is poorly documented. We aim to characterize concurrency in a more accurate and complete manner, using data from three disadvantaged communities of Cape Town, South Africa.

Methods

We conducted a sexual behaviour survey (n=878) from June 2011 to February 2012 in Cape Town, using Audio Computer-Assisted Self-Interviewing to collect sexual relationship histories on partners in the past year. Using the beginning and end dates for the partnerships, we calculated the point prevalence, the cumulative prevalence and the incidence rate of CPs, as well as the duration of overlap for relationships begun in the previous year. Linear and binomial regression models were used to quantify race (black vs. coloured) and sex differences in the duration of overlap and relative risk of having CPs in the past year.

Results

The overall point prevalence of CPs six months before the survey was 8.4%: 13.4% for black men, 1.9% for coloured men, 7.8% black women and 5.6% for coloured women. The median duration of overlap in CPs was 7.5 weeks. Women had less risk of CPs in the previous year than men (RR 0.43; 95% CI: 0.32–0.57) and black participants were more at risk than coloured participants (RR 1.86; 95% CI: 1.17–2.97).

Conclusions

Our results indicate that in this population the prevalence of CPs is relatively high and is characterized by overlaps of long duration, implying there may be opportunities for HIV to be transmitted to concurrent partners.  相似文献   
80.
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