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991.
The purpose of this study was to determine if the use of a retention strategy would maintain cardiopulmonary resuscitation (CPR) skills in family members of cardiac patients. Thirty-one subjects trained in CPR received retention packets 3 and 6 months after CPR training. Sixteen subjects were tested for CPR retention at 7 months after initial training, and 15 at 12 months. Likelihood chi 2 was used to compare the 7- and 12-month groups. There were no differences between the 7- and 12-month groups, because CPR retention overall was poor. Only 19.4% of subjects reported using the retention packet; therefore, subjects were regrouped into practice and no practice groups for purposes of further statistical analysis. There were significant differences in retention in subjects who practiced compared with subjects who did not. These findings underscore the importance of promoting practice/review after initial CPR training for family members of cardiac patients.  相似文献   
992.
1. The effect of a variation in inspiration and expiration times on heart rate variability was studied in 12 healthy subjects (mean age 30+/-6 years; five females). 2. Two 2 min trials of controlled breathing, with either short inspiration followed by long expiration or long inspiration followed by short expiration, were compared. Average expiration/inspiration time ratios were 1.0 and 3.4, respectively. The respiration rate in both trials was approximately 10 cycles/min. 3. In trials with short inspiration followed by long expiration, respiratory sinus arrhythmia (RSA; as measured by mean absolute differences and by the high frequency band) was significantly larger than in trials with long inspiration followed by short expiration. This effect could not be accounted for by differences in respiration rate or respiratory amplitude. The higher RSA during fast/slow respiration is primarily due to a more pronounced phasic heart rate increase during inspiration, indicating that inspiratory vagal blockade is sensitive to the steepness of inspiration. 4. Respiration rate and tidal volume are respiratory variables known to modulate RSA. The results of the present study indicate that RSA can also be modulated by a third respiratory variable, the expiratory/inspiratory time ratio.  相似文献   
993.
The estuarine dinoflagellate Pfiesteria piscicida is known to kill fish and has been associated with neurocognitive deficits in humans. We have developed a rat model to demonstrate that exposure to Pfiesteria causes significant learning impairments. This has been repeatedly seen as a choice accuracy impairment during radial-arm maze learning. Pfiesteria-induced effects were also seen in a locomotor activity test in the figure-8 apparatus. The current studies used the short-term radial-arm maze acquisition, the figure-8 activity test, and the functional observational battery (FOB) to assess Pfiesteria-induced neurobehavioral effects in adult and juvenile rats. In study 1, the neurobehavioral potency of three different Pfiesteria cultures (Pf 113, Pf 728, and Pf Vandermere) was assessed. Ninety-six (12 per group) adult female Sprague-Dawley rats were injected subcutaneously with a single dose of Pfiesteria taken from aquarium-cultured Pfiesteria (35,600 or 106,800 Pfiesteria cells per kilogram of rat body weight). One control group (N = 12) was injected with saline and one (N = 12) with aquarium water not containing Pfiesteria. All three of the Pfiesteria samples (p < 0.05) impaired choice accuracy over the first six sessions of training. At the time of the radial-arm maze choice accuracy impairment, no overt Pfiesteria-related effects were seen using an FOB, indicating that the Pfiesteria-induced choice accuracy deficit was not due to generalized debilitation. In the figure-8 apparatus, Pfiesteria treatment caused a significant decrease in mean locomotor activity. In study 2, the neurobehavioral effects of the Pf 728 sample type were assessed in juvenile rats. Twenty-four day-old male and female rats were injected with 35,600 or 106,800 Pf-728 Pfiesteria cells per kilogram of rat body weight. As with adult females, the juvenile rats showed a significant impairment in radial-arm maze choice accuracy. No changes in locomotor activity or the FOB were detected in the juvenile rats. Furthermore, there were no differences between male and female rats in the Pfiesteria-induced choice accuracy impairment. Pfiesteria effects on choice accuracy in the radial-arm maze in rats constitute a critical component of the model of Pfiesteria toxicity, because the hallmark of Pfiesteria toxicity in humans is cognitive dysfunction. Our finding that analysis of the first six sessions of radial-arm maze testing is sufficient for determining the effect means that this test will be useful as a rapid screen for identifying the critical neurotoxin(s) of Pfiesteria in future studies.  相似文献   
994.
The Western Canadian Gastrointestinal Cancer Consensus Conference (WCGCCC) convened virtually on 4 November 2021. The WCGCCC is an interactive multi-disciplinary conference attended by health care professionals, including surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals from across four Western Canadian provinces, British Columbia, Alberta, Saskatchewan, and Manitoba, who are involved in the care of patients with gastrointestinal cancer. They participated in presentation and discussion sessions for the purpose of developing recommendations on the role of systemic therapy and its optimal sequence in patients with resectable metastatic colorectal cancer.  相似文献   
995.
Cardiac positron emission tomography is a noninvasive imaging modality that can be used to assess regional myocardial blood flow and metabolism. This combined noninvasive approach to the evaluation of acute or chronic injury to the myocardium is superior to all other imaging modalities. With increasingly widespread use of positron emission tomography it is becoming evident that patients with impaired left ventricular ejection fraction (less than or equal to 35%) resulting from congestive heart failure and patients soon (72-96 h) after acute myocardial infarction in particular may benefit from definition of metabolically active myocardium to stratify therapeutic assessment.  相似文献   
996.
Purpose: To discuss treatment modalities for aggressive posterior retinopathy of prematurity (AP‐ROP). Methods: The medical charts of all infants with AP‐ROP at Uppsala University Hospital, Sweden, during a 2‐year period (2009 and 2010) were reviewed. Eight infants (16 eyes) with a mean gestational age of 23.8 weeks and a mean birth weight of 592 g were treated with laser and/or intravitreal injections of bevacizumab (0.4 and 0.625 mg). RetCam photography was used to document the retinal appearance before and after treatment. Results: All infants (16 eyes) had AP‐ROP in zone I. Mean time at initial treatment was 34 weeks postmenstrual age. Two eyes (one infant) were only treated with laser, and six eyes (three infants) were treated with laser therapy or cryopexy and, because of lack of regression, with bevacizumab as salvage therapy. Eight eyes (four infants) were treated with a first‐line bevacizumab injection and four of these eyes (two infants) with additional laser ablation for continued disease progression in zone II. Macular dragging occurred in one eye of one infant primarily treated with laser. Conclusions: Given the high complication rate of the extensive laser treatment for zone I ROP, it is worth considering anti‐vascular endothelial growth factor treatment as an alternative therapy. Further knowledge concerning side effects and long‐term ocular and systemic outcome is warranted before this drug becomes general clinical practice.  相似文献   
997.

Background:

In the United Kingdom, breast cancer incidence is lower in South Asian and Black women than in White women, but the extent to which this is due to known risk factors is unknown. In a large prospective study, we describe breast cancer incidence by ethnicity, before and after adjustment for known risk factors for the disease.

Methods:

Women were recruited into the Million Women Study in 1996–2001, when information on reproductive and lifestyle factors known to influence the risk of breast cancer was obtained. Ethnicity was determined from study questionnaires and hospital admission data. Cox regression models were used to calculate adjusted relative risks (RR) for incident breast cancer in South Asians and Blacks compared with Whites.

Results:

Analyses included 5877 South Asian, 4919 Black, and 1 038 144 White women in England. The prevalence of 8 out of the 9 risk factors for breast cancer examined, differed substantially by ethnicity (P<0.001 for each), such that South Asian and Black women were at a lower risk of the disease than White women. During 12.2 years of follow-up incident breast cancer occurred in 217 South Asians, 180 Blacks, and 45 191 Whites. As expected, breast cancer incidence was lower in South Asians (RR=0.82, 95% CI 0.72–0.94) and Blacks (RR=0.85, 0.73–0.98) than in Whites when the analyses were adjusted only for age and region of residence. However, after additional adjustment for the known risk factors for the disease, breast cancer incidence was similar to that of Whites, both in South Asians (0.95, 0.83–1.09) and in Blacks (0.91, 0.78–1.05).

Conclusion:

South Asian and Black women in England have lower incidence rates of breast cancer than White women, but this is largely, if not wholly, because of differences in known risk factors for the disease.  相似文献   
998.
In doing a case-control study of cancer of the exocrine pancreas, a set of criteria was developed to classify cancer of the exocrine pancreas by pathological and diagnostic data as to the probability that the tumor arose in the pancreas. We applied these criteria to the records of 125 consecutive patients between the ages of 40-79 years who were identified as having adenocarcinomas of the exocrine pancreas from a population-based cancer registry. We found that histological confirmation by a cancer registry does not guarantee the site of origin is the pancreas. Of the histologically confirmed cases meeting our study criteria, 28.7% may not have arisen in the pancreas. Forty-seven per cent of non-histologically confirmed cases, which most studies exclude, were almost certainly of pancreatic origin based on computerized tomogram (CT) scan and/or surgical palpation and subsequent clinical course. These figures may underestimate the full extent of diagnostic misclassification, especially in older age groups. We conclude that epidemiological studies of cancer of the exocrine pancreas need more uniform criteria for defining cases, and these criteria should take into account uncertainty as to site of origin. Sufficient detail of our scheme is presented so it can be applied in other studies.  相似文献   
999.
Kürsteiner O  Moser C  Lazar H  Durrer P 《Vaccine》2006,24(44-46):6632-6635
The antigen used in influenza vaccines is directly derived from influenza viruses. It is produced in embryonated chicken eggs for both inactivated and live attenuated influenza vaccines. As a consequence, all influenza vaccines contain varying amounts of residual egg proteins, depending on the specific manufacturing process of the vaccine. The degree of purity of influenza vaccines can be assessed by quantifying the total amount of protein in relation to the amount of specific antigen. Alternatively, ovalbumin can be used as surrogate marker, representing the amount of egg-derived proteins present in the vaccine. Egg proteins, such as ovalbumin, are classified as sensitising agents. Their presence in a vaccine may be linked to adverse reactions. Such a vaccine is not suitable for subjects with a known history of egg-allergy. This population is currently excluded from influenza vaccination programs. Influenza vaccines are intended for annual re-immunisation. This repeated administration may lead to an immunity against ovalbumin and other egg proteins, which in turn may provoke increased local and systemic reactions and a reduced tolerability profile of the product. Comparing several influenza vaccines present on the market, ELISA and Western blot analysis showed clearly a very low level of ovalbumin in Inflexal V. Furthermore, data showed, that Inflexal V is the influenza vaccine with the lowest ovalbumin content.  相似文献   
1000.
Earthworms play key roles in soils and sub-lethal effects of environmental toxicants on these organisms should be taken seriously, since they might have detrimental effects on higher ecological levels. In laboratory experiments we have assessed sub-lethal effects (body mass change and cast production) of imidacloprid on two earthworm species commonly found in different agricultural soils (Lumbricus terrestris and Aporrectodea caliginosa). After 7 days of exposure in contaminated soil, a significant loss of body mass was found in both species exposed to imidacloprid concentrations as low as 0.66 mg kg?1 dry soil. These losses ranged from 18.3 to 39% for A. caliginosa and from 7.4 to 32.4% for L. terrestris, respectively. Changes in cast production, a new biomarker previously validated using L. terrestris, was assessed by soil sieving using the recommended mesh size (5.6 mm) for L. terrestris and three different mesh sizes for A. caliginosa (5.6, 4 and 3.15 mm). The 4 mm mesh size proved to be the most suitable sieve size for A. caliginosa. Cast production increased by 26.2% in A. caliginosa and by 28.1% in L. terrestris at the lowest imidacloprid concentration tested (0.2 mg kg?1 dry soil), but significantly decreased at higher concentrations (equal to and above 0.66 mg kg?1 dry soil) in both earthworm species after the 7 days exposure experiment. These decreases in cast production ranged from 44.5 to 96.9% in A. caliginosa and from 42.4 to 95.7% in L. terrestris. The EC50 for cast production were 0.84 (L. terrestris) and 0.76 mg kg?1 dry soil (A. caliginosa), respectively. The detected sub-lethal effects were found close to the predicted environmental concentration (PEC) of imidacloprid, which is in the range of 0.33–0.66 mg kg?1 dry soil. The biomarkers used in the present study, body mass change and changes in cast production, may be of ecological relevance and have shown high sensitivity for imidacloprid exposure of earthworms. The measurement of changes in cast production should be considered for inclusion in current standard tests.  相似文献   
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