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11.
A young dog with progressive neurological signs was humanely killed by the injection of barbiturate for postmortem examination. Lesions in the nose, lung, pancreas, lymph nodes, kidneys and the meninges were heavily infiltrated with Cryptococcus neoformans. In addition, haemangiosarcoma was detected in the right atrium. The finding of systemic mycosis and neoplasia together in a young dog suggests an immunosuppressed state.  相似文献   
12.
Professor Nicola Cherry has taken the Chair of OccupationalMedicine at Manchester University. At a unique event on 28 February1991, the three Emeritus Professors met Professor Cherry ata meeting held at the A.M.I. Alexandra Hospital, Cheadle, Manchester.The meeting organized by the North West Group of the SOM, includeda tour of the hospital followed by a buffet supper. ProfessorLane (now aged 94) introduced Professor Cherry who gave a talkon her first impressions on return from McGill University andher future objectives. Over 70 members of the SOM, BOHS andRCN Greater Manchester Group of OH nurses attended.  相似文献   
13.
Surgical treatment of spinal chordomas   总被引:5,自引:0,他引:5  
The clinical features and results of 34 patients with chordomas treated over a seven-year period were analyzed. Surgical treatment consisted of wide local excision (n = 6), marginal resection (n = 5), intralesional resection (n = 20), and biopsy (n = 3). Eighteen patients received postoperative radiotherapy. The local recurrence rate was 65%, with 30% of patients developing distant metastases. With the introduction of computed tomography, smaller tumors are currently being diagnosed; as a result, 35% of the patients in this series are disease free, compared with 10% described previously.  相似文献   
14.
Neurological sequelae of hypothyroidism are well recognized and relatively common. Neurological symptoms occurring as a presenting feature of this illness are, however, uncommon. Here we report three patients who presented in such a way and in whom the diagnosis was only suspected because of slow relaxing reflexes.  相似文献   
15.
Dynamic rotation is a computer-controlled therapy technique utilizing an automated multileaf collimator in which the radiation beam shape changes dynamically as the treatment machine rotates about the patient so that at each instant the beam shape matches the projected shape of the target volume. In simple dynamic rotation, the dose rate remains constant during rotation. For optimized dynamic rotation, the dose rate is varied as a function of gantry angle. Optimum dose rate at each gantry angle is computed by linear programming. Wedges can be included in the optimized dynamic rotation therapy by using additional rotations. Simple and optimized dynamic rotation treatment plans, with and without wedges, for a pancreatic tumor have been compared using optimization cost function values, normal tissue complication probabilities, and positive difference statistic values. For planning purposes, a continuous rotation is approximated by static beams at a number of gantry angles equally spaced about the patient. In theory, the quality of optimized treatment planning solutions should improve as the number of static beams increases. The addition of wedges should further improve dose distributions. For the case studied, no significant improvements were seen for more than 36 beam angles. Open and wedged optimized dynamic rotations were better than simple dynamic rotation, but wedged optimized dynamic rotation showed no definitive improvement over open beam optimized dynamic rotation.  相似文献   
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A nonisotopic assay of vitamin B-12 in human serum or plasma is described, performed with the Abbott IMx analyzer. The sample is first treated at pH > 12.5 to release bound vitamin B-12 and to convert all forms to cyanocobalamin. Next, the analyte is bound, at lower pH, by vitamin B-12-specific binding protein, immobilized to a solid phase of polymeric microspheres. Detection involves monitoring the activity of the tracer enzyme (alkaline phosphatase) coupled to a derivative of cyanocobalamin. Total assay precision is 7.9% for vitamin B-12 at 200 ng/L, 6.6% at 400 ng/L, and 6.7% at 800 ng/L. Assay sensitivity, calculated as 2 SD from the zero calibrator, is 37 (+/- 9) ng/L. The dynamic range extends to 2000 ng/L. Analytical recovery of 300 and 600 ng/L additions of vitamin B-12 to sera with basal concentrations of 30-400 ng/L was 102.5%. Results of the assay correlated well with those of commercially available radioisotope assays. No interference was observed in specimens from patients with pernicious anemia, chronic or acute myelogenous leukemia, or renal failure. Cross-reactivity with cobinamide (1 g/L) was < 0.00003%. Vitamin B-12 measurements for blood specimens drawn into serum, EDTA, or heparinized plasma-collection tubes agreed within 3%.  相似文献   
18.
PURPOSETo evaluate mechanically detachable coil designs capable of controlled and instantaneous release within an aneurysm or vascular space.METHODSThree mechanically detachable coil designs, clamped ball, looped ribbon, and interlocking cylinder, were evaluated using in vitro and in vivo testing to study reliability of coil release, retractability, and coil behavior in a microcatheters. In vitro tests were performed using a glass side-wall aneurysm model and conventional microcatheters. In vivo experiments in rabbits included aneurysm models (side-wall and bifurcation) and arterial occlusions (carotid and renal).RESULTSAll three designs deployed coils easily and were able to retract coils after partial deployment. Motion was seen in previously released coils and in the catheter when using the clamped ball and looped ribbon designs. The interlocking cylinder design did not cause similar motion. When compared with the other two designs, the interlocking cylinder had significantly greater separation forces between coil pusher and coil while in the catheter. Frictional forces within the catheter were lower for the interlocking cylinder mechanically detachable coil design than for a commercially available conventional coil and coil pusher system. During in vivo testing, the mechanically detachable coil design operated smoothly in the catheter, providing good release and retraction in aneurysms and straight vessels.CONCLUSIONThe interlocking cylinder mechanically detachable coil design is superior to the other two tested designs. The mechanically detachable coil was reliably delivered and detached in in vivo testing for the treatment of aneurysms and for the occlusion of blood vessels.  相似文献   
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20.
An 8-year longitudinal study of elderly people has provided data concerning age-associated impairment (AAMI). In 1985 a random sample of 146 persons aged 65 years or more, living in their own homes, were assessed using the Guild Memory Test the Mini–Mental State Examination (MMSE) and other ratings. After excluding 21% of the sample because they scored less than 24 on the MMSE, and another 34% who fulfilled other exclusion criteria, some 48% of the remainder (22% of the total sample) clearly fulfilled NIMH criteria for AAMI and a further 36% (16% of the total sample) were recorded as forgetful. The NIMH criteria are appropriate for certain research purposes but not in assessing prevalence of memory disorders. Follow–up interviews were conducted after 2, 4, 6 and 8 years. The mortality rate and development of dementia among those fulfilling criteria for AAMI appeared similar to the other non-demented groups of subjects; the mortality rate of those with MMSE scores below 24 was significantly higher. Guild test results at 2-yearly intervals showed considerable changes; half of those scoring least well who were retested showed improvement.  相似文献   
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