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911.
Robin R. A. Coombs 《Vox sanguinis》1998,74(2):67-73
This is a review of two invited talks on the antiglobulin reaction on the occasion of the 50th Anniversaries of the International Blood Group Reference Laboratory, now at Bristol, and the National Blood Service, London, and coincidentally the 51st anniversary of the antiglobulin test! The first talk (as specially requested) is a very personal reminiscence of the discovery, with Rob Race and Arthur Mourant, of the antiglobulin test in blood group serology. The second talk traces developments in antiglobulin testing in general immunology using, of course, isotype-specific antiglobulin reagents as and when they became available. Special emphasis was given to: (1) testing for poorly agglutinating bacterial antibodies; (2) special procedures for measuring reaginic (IgE) antibodies to various allergens; (3) the incorporation of an antiglobulin step or stage in many of the routine automated immunoassay procedures; (4) the special experimental procedures in the form of mixed antiglobulin reactions to reveal antibodies to the surface antigens on tissue cells, and, finally, (5) by chemically coupling antiglobulin to red blood cells, a distinctive integrated immunoassay system was developed, enabling reverse passive haemagglutination as an assay for immunoglobulins, rosetting reactions to reveal native IgG receptors on lymphocytes or antibody immunoglobulin reacting with CD marker antigens; this same reagent, namely red-cell-labelled antiglobulin, can be used to detect antibodies reacting with either bacteria or antigens adsorbed on the walls of wells of microtitre plates. The need for improved stabilization and preservation of the antiglobulin-linked red cells to prolong their ‘shelf-life’ is stressed. 相似文献
912.
Improved health education has the potential to increase theproportion of people with early melanoma presenting to doctors.This study was designed to evaluate experimentally the effectsof various types and amounts of information on early melanomadetection. One hundred and fifty-one subjects assessed 157 skinlesions on 34 separate photographs of areas of skin and markedthose for which they would seek medical attention if they foundit on their skin. They were then provided with one of five differentexperimental brochures and using the information in the brochurerepeated the lesion-marking task. An overall increase in sensitivitywas found. Specificity and predictive value both were betterwhen more information was provided. Thus, provision of conciseand relevant information about melanoma, perhaps accompaniedby colour photographs, and information about non-melanoma lesionsprovided the best overall detection of melanoma from photographsof skin lesions. Brochures providing such information have thepotential to improve the predictive value of skin self-examinationfor melanoma detection. 相似文献
913.
The histidine utilization genes hutH and hutU of Pseudomonas putida ATCC 12633 have been mapped by interrupted mating and transduction to a location at approximately 43 minutes on the chromosome, closely linked to ser-800 and met-400 markers previously shown to be at 46 and 42 minutes, respectively. Since restriction enzyme mapping and cloning results have established that all genes associated with the hut pathway are contiguous, earlier maps of this strain which place these genes near 10 minutes on the chromosome in a superoperonic catabolic cluster are in error. 相似文献
914.
Burnout may develop in highly productive, hard-working individuals from all walks of life. Extending working hours under stressful circumstances may produce a sense of frustration resulting in emotional exhaustion, loss of empathy for patients, and a decreased sense of personal accomplishment. The membership of the American Society of Head and Neck Surgery and the Society of Head and Neck Surgeons was surveyed by mail relative to burnout. A total of 395 head and neck surgeons responded. Mean age was 48 years. The average individual worked an average of 66 hours per week. More than 70% of work was devoted to patient care of which 30% to 50% was devoted to the management of head and neck cancer. A total of 128 (34%) individuals responded that they felt “burned out.” Only 27%, however, indicated frustration with disease, whereas 67% indicated frustration by government and 58% indicated frustration by the economics of medical practice. Most respondents enjoy their work, nevertheless, the stress of extending working hours dealing with severely ill patients, and the increased need to deal with government and economic issues is of concern to the community of physicians practicing head and neck surgery. Discussion about and confrontation with these issues are appropriate to facilitate and enhance an individual's ability to continue to function productively in this environment. 相似文献
915.
Harold H. Morris Melinda L. Estes Robin Gilmore Paul C. Van Ness Gene H. Barnett John Turnbull 《Epilepsia》1993,34(6):1038-1043
We identified 39 patients with chronic epilepsy (seizures ≥2 years) proven to have primary brain tumors. These cases represent ~12% of the surgery cases for epilepsy in the same period. Mean age of seizure onset was 13.2 years: mean duration before operation was 10.5 years. Thirty-eight of 39 had normal neurologic examination. Twenty-six tumors were temporal, 7 were frontal, 4 were parietal, and 2 were occipital. Nine of 26 (34.6%) of the temporal group had contralateral interictal EEG spikes. Pathology was 15 ganglioglioma, 13 low-grade astrocytoma, 4 oligodendroglioma, 2 low-grade mixed glioma, 1 pleomorphic xanthoastrocytoma, 2 dysembryoplastic neuroepithelial tumor, and 1 ependymoma. Postoperative seizure frequency (minimum follow-up 6 months) ranged from 15 to 16 seizure-free or auras only in patients with temporal tumors and total gross tumor removal (mean follow-up 28 months) to 0 of 6 seizure-free in patients with extratemporal tumors who underwent subtotal resections or biopsy. 相似文献
916.
Alexander V. Ng PhD David G. Johnson MD Robin Callister PhD Douglas R. Seals PhD 《Clinical autonomic research》1995,5(1):57-60
Recent evidence suggests that during orthostatic stress the reflex increase in muscle sympathetic nerve activity may be diminished in older adults. To test this hypothesis, we measured muscle sympathetic nerve activity, plasma noradrenaline concentrations, heart rate, and arterial blood pressure in twelve young (mean, 25 years; range, 19–29 years) adults and 14 older (mean 64 years; range, 60–74 years) healthy adults, while supine and during upright sitting. Supine control levels of muscle sympathetic nerve activity were higher in the older subjects (35 ± 1 vs. 25 ± 1 bursts/min,p < 0.05), but there were no differences in plasma noradrenaline concentrations, heart rate or arterial pressure. Despite higher supine control levels in the older group, the absolute unit increases in muscle sympathetic nerve activity in response to upright sitting (p < 0.05 vs. control) were not different in the two groups (7 ± 1 vs. 7 ± 1 bursts/min), nor were the increases in plasma noradrenaline concentrations. Heart rate did not increase above supine control in response to sitting in either group. Arterial pressure increased slightly (p < 0.05, supine vs. control), but there were no age-related differences. These results indicate that, contrary to recent findings, the reflex increases in muscle sympathetic nerve activity and plasma noradrenaline concentrations and regulation of arterial pressure during this natural orthostatic stress are well preserved in older healthy men and women. 相似文献
917.
Robin D. Wood Ezio Tirelli Kristyn J. Snyder Charles J. Heyser Tara M. LaRocca L. P. Spear 《Psychopharmacology》1998,138(2):114-123
While chronic intermittent administration of stimulants often induces behavioral sensitization in adulthood, stimulant sensitization
has rarely been reported prior to weaning [around postnatal day (P) 21]. Consistent pairing of drug administration with the
test context often facilitates sensitization in adults, yet young animals have been typically returned to the home cage immediately
post-injection. To determine whether promoting context-dependent sensitization might facilitate expression of sensitization
in preweanlings, Sprague-Dawley rats were injected daily from P14 to P20 with 0, 5, 15, or 30 mg/kg cocaine HC1 and placed
for 30 min in either the experimental chamber or home cage. On P21 (test day), subjects were challenged with either 15 mg/kg
cocaine or saline prior to placement in the experimental chamber. Significant sensitization of cocaine-induced stereotyped
head movements was evident in animals given 15 or 30 mg/kg chronically in the experimental chamber, but not when these same
doses were given in the home cage. Less consistent evidence for cocaine-induced sensitization was seen when examining locomotion,
although trends for sensitization of this behavior were seen in animals chronically injected in either the test chamber or
home cage. Thus, preweanlings can exhibit cocaine sensitization, particularly in terms of stereotypy, when tested shortly
after the chronic exposure period, with expression of this sensitization being facilitated by pairing the chronic injections
with the test context.
Received: 19 November 1996/Final version: 10 December 1997 相似文献
918.
919.
Computed tomographic analysis of renal calculi 总被引:3,自引:0,他引:3
B J Hillman G W Drach P Tracey J A Gaines 《AJR. American journal of roentgenology》1984,142(3):549-552
An in vitro study sought to determine the feasibility of using computed tomography (CT) to analyze the chemical composition of renal calculi and thus aid in selecting the best treatment method. Sixty-three coded calculi were scanned in a water bath. Region-of-interest measurements provided the mean, standard deviation, and minimum and maximum pixel values for each stone. These parameters were correlated with aspects of the stones' chemical composition. A multivariate analysis showed that the mean and standard deviation of the stones' pixel values were the best CT parameters for differentiating types of renal calculi. By using computerized mapping techniques, uric acid calculi could be perfectly differentiated from struvite and calcium oxalate calculi. The latter two types also were differentiable, but to a lesser extent. CT has a potential role as an adjunct to clinical and laboratory methods for determining the chemical composition of renal calculi in an effort to select optimal treatment. 相似文献
920.
Robin Haynes 《Social science & medicine (1982)》1983,17(6):355-364
Standardised mortality ratios for 19 causes of death are computed for the provinces of Chile. All have a particular geographical distribution in common: they are either positively or negatively associated with the availability of health services. This is likely to be the result of the propinquity of health services to populations of higher socio-economic status and also the differences in recording accuracy between urbanised provinces and provinces where access to health services is especially difficult. By holding the effects of health service variability constant, other geographical patterns in mortality rates emerge. For lung cancer, two northern provinces have death rates ten times those of central Chile. 相似文献