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11.
12.
P. A. Sylvester E. Kutt A. Baird M. N. Vipond A. J. Webb J. R. Farndon 《Annals of the Royal College of Surgeons of England》1997,79(4):276-277
There has been concern about the number of interval cancers which have been detected within the National Breast Screening Programme. A series of 134 women presenting with interval cancers was studied by prospective audit and the rate and radiological classification of the tumours determined. The cancers were classified as true (67), false-negative (22), unclassifiable (28), occult (12), and minimal sign (5). The interval cancer rate did not achieve the new National Guidelines in either the first 2 years or the 3rd interval year. The false-negative cancers presented mainly in the 1st interval year, whereas the true cancers were predominantly confined to the 2nd and 3rd years. These data suggest that alterations to the screening programme may be beneficial. It may be, however, that the programme is still on the learning curve and this should be taken into account when interpreting these data. 相似文献
13.
M. Medina C. Barata T. Telfer D. J. Baird 《Archives of environmental contamination and toxicology》2002,42(1):17-22
Acute effects of cypermethrin, a pesticide used to treat ectoparasite infestations of salmon, were assessed using the calanoid
copepod Acartia tonsa. A. tonsa has been widely used for hazard assessment of chemicals in the marine environment using acute toxicity tests, but only with
randomly selected adults, assuming a sex ratio of 1:1. The present study assesses the environmental hazard of cypermethrin
by exposing nauplii and adult males and females, separately. Our results showed that the naupliar stages were 28 times more
sensitive to cypermethrin than adults after 96 h of exposure, with LC50s of 0.005 μg L−1 and 0.142 μg L−1, respectively. Significant differences in sensitivity between sexes were only found during the first 24 h of exposure, with
males being approximately twice as sensitive as females. The results of age-related variation in sensitivity are supported
by studies with other species of copepods and toxicants, where the increased capacity of the adults for detoxification, the
allometric differences in weight and size, and the molting process are given as explanations. Variation in sensitivity between
sexes is discussed in terms of faster depuration rates in females through egg production and implications of feeding rate
changes after 24 h of exposure. Our results suggested that standard toxicity test methods using A. tonsa are unsatisfactory because the most sensitive life stage is not included and sex-related differences in tolerance are not
taken into account. We also found that cypermethrin caused significant mortality in Acartia at exposures concentrations from one to three orders of magnitudes lower than the recommended field treatment concentration
for copepodic infestations.
Received: 27 April 2001/Accepted: 1 July 2001 相似文献
14.
Identifying blood biomarkers may be of particular value in neurologic disorders such as stroke because of the difficulty in
directly studying the brain and its blood vessels. Markers of brain injury, inflammation, excitotoxicity, and oxidative damage
have been evaluated for their value in stroke diagnosis, treatment, and management, but none has proved to be sensitive or
specific enough for routine clinical use. However, new cellular and molecular profiling approaches using the peripheral blood
offer the potential for identifying panels of genes and proteins by increasing specificity while maintaining sensitivity.
Furthermore, the first biomarker for predicting stroke risk associated with atherosclerosis (lipoprotein-associated phospholipase
A2) was recently approved by the United States Food and Drug Administration. The ultimate aim for stroke biomarkers is to develop
rapid, easy to use, widely available, and inexpensive diagnostic tests that can be used in the clinic and in clinical trials. 相似文献
15.
Blood loss following induction of early abortion using mifepristone (RU 486) and a prostaglandin analogue (gemeprost) 总被引:1,自引:0,他引:1
The pattern and amount of blood loss following induction of therapeutic abortion using mifepristone (RU 486) and a prostaglandin E analogue (gemeprost) was studied in 222 women of less than 63 days amenorrhoea. A single oral dose of mifepristone (400, 500 or 600 mg) was followed 48 hours later by a half or 1 mg gemeprost vaginal pessary. Complete abortion occurred in 218 (98%) women without necessity for surgical evacuation of the uterus. Bleeding commonly occurred following administration of mifepristone and prior to prostaglandin administration. The median duration of bleeding following abortion was 13 days with a range of from 1 to 44 days. There was a wide individual variation in measured blood loss between women, from 14 to 512 ml, with a median loss of 74 ml. The amount of blood loss was independent of the dose of mifepristone or prostaglandin but was significantly correlated with gestation. These results confirm that the combination of mifepristone and gemeprost is a highly effective and safe method of inducing therapeutic abortion medically. As the amount of blood loss increases with increasing gestation, it is suggested that its use should be restricted to women with amenorrhoea less than or equal to 56 days. 相似文献
16.
Combinations of murine recombinant interleukin 3 (IL-3), purified murine macrophage colony-stimulating factor (M-CSF), and human recombinant interleukin 1 alpha (IL-1 alpha) were used to determine the effects of growth factors on the measured radiosensitivity of different populations of murine colony-forming cells (CFC). The data showed that combinations of growth factors resulted in different values of CFC radiosensitivity, being less than values observed when colony growth was stimulated using a single factor. For various combinations of growth factors, Do values ranged from 106 +/- 8 to 175 +/- 24 cGy for progenitor cells in normal bone marrow; 74 +/- 3 to 171 +/- 18 cGy for primitive multipotent CFC enriched using fluorescence-activated cell sorting; and from 46 +/- 4 to 131 +/- 10 cGy for more mature granulocyte-macrophage CFC, enriched by counterflow centrifugal elutriation. Only combinations of three factors produced the high values of Do reported in experiments using unpurified conditioned medium as a stimulus for colony formation. 相似文献
17.
BACKGROUND: It has been established that individuals who score high on measures of psychopathy demonstrate difficulty when performing tasks requiring the interpretation of other's emotional states. The aim of this study was to elucidate the relation of emotion and cognition to individual differences on a standard psychopathy personality inventory (PPI) among a nonpsychiatric population. METHODS: Twenty participants completed the PPI. Following survey completion, a mean split of their scores on the emotional-interpersonal factor was performed, and participants were placed into a high or low group. Functional magnetic resonance imaging data were collected while participants performed a recognition task that required attention be given to either the affect or identity of target stimuli. RESULTS: No significant behavioral differences were found. In response to the affect recognition task, significant differences between high- and low-scoring subjects were observed in several subregions of the frontal cortex, as well as the amygdala. No significant differences were found between the groups in response to the identity recognition condition. CONCLUSIONS: Results indicate that participants scoring high on the PPI, although not behaviorally distinct, demonstrate a significantly different pattern of neural activity (as measured by blood oxygen level-dependent contrast)in response to tasks that require affective processing. The results suggest a unique neural signature associated with personality differences in a nonpsychiatric population. 相似文献
18.
The purpose of this study was to determine the accuracy of FirstTemp (Intelligent Medical Systems, Carlsbad, CA) tympanic thermometer readings compared with core body temperatures obtained via pulmonary artery catheter (PAC). Five measurements were obtained on 19 cardiovascular surgery patients. Tympanic thermometer measurements tended to be higher than PAC measurements. However, most of the differences were not clinically significant. Differences found between right and left ear measurements were most likely due to poor measurement technique. When the correct technique is used, nurses can be confident that tympanic temperature readings are clinically accurate. 相似文献
19.
Functional impact of attachment and purification in the short term culture of human pancreatic islets 总被引:2,自引:0,他引:2
G M Beattie D A Lappi A Baird A Hayek 《The Journal of clinical endocrinology and metabolism》1991,73(1):93-98
We have evaluated the effects on islet function of several manipulations of the substrate and tissue culture conditions in the short term culture of human islets. Specifically, we have studied the influence of several matrices, additions to the medium, and the use of basic fibroblast growth factor (FGF)-saporin mitotoxins to eliminate fibroblastoid cells from the cultures. The human islets were obtained from the Human Islet Transplant Center at Washington University Medical Center (St. Louis, MO). Substrates used to facilitate islet attachment were poly-L-lysine, gelatin, Matrigel, collagen, and bovine corneal endothelial cell matrix. RPMI-1640 medium was supplemented with either 22.2 mM glucose or 10 micrograms/mL human insulin. FGF-saporin mitotoxin was used at a concentration of 10 nM. The greatest improvement in islet cell function in either static or stimulated situations was obtained when we used bovine corneal endothelial cell matrix as the matrix, supplemented the medium with a high concentration of glucose or insulin, and eliminated fibroblast-like cells by exposing the cultures to basic FGF-saporin mitotoxin. The conditions described in this report could greatly improve the culture of human islets for use in clinical and laboratory research. 相似文献
20.
A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described. 相似文献