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51.
One hundred and sixty-four patients admitted to a psychogeriatric unit were given a combination of four different cognitive tests: the Mini Mental State Examination (MMSE), the Abbreviated Mental Test Score, The Felix Post Unit Score and the compilation of tests recommended by the MRC Alzheimer's Disease Workshop. The tests were compared with respect to their ability to sort accurately cases of dementia and depression, and the effects of age and education on test score and misclassification rate with diagnosis controlled for. The MMSE had a very high misclassification rate for the poorly educated and depressed group. The logistical discriminant functional analysis selected only eight items as the best discriminators between organic/ functional or dementia/depression groups. Only one of these eight was not either a memory or orientation test. The value of simply adding up tests of different aspects of cognitive function in dementia assessment or screening is questioned.  相似文献   
52.
Official cancer mortality in Switzerland decreased by about 16% over the 9-year period 1990-1998 and this trend has often been used to suggest that secondary prevention by screening for breast cancer could be useless. However, the clear downshift observed between 1994 and 1995 for some cancers, such as female breast and prostate, and the simultaneous change in ICD classification used by the Federal Office for Statistics in 1995 (ICD-8 to ICD-10) could be related, suggesting an impact of coding process on the observed trend. For every death occurred between 1980 and 1999, the death certificates have been retrieved, the cause of death has been recoded and site-specific mortality rates have been calculated again for each year during this period. As suggested, the trend appears to be overestimated: in order to be comparable with current rates, the mortality observed before 1995 should be lowered by about 7% for men and 5% for women. The error may be partially due to attributing the cause of death to co-morbidity factors not normally (and nowadays) defined as the underlying cause. Logically, the impact of such a miscoding is more important among older people and for cancer sites with long survival. For instance, the correction should be around 15% for female breast, 12% for prostate and up to 40% for testicular cancer.  相似文献   
53.
Repeated measures of wavefront aberrations were taken along the line-of-sight of seven eyes using two instruments: an objective, cross-cylinder aberroscope (OA) and a Shack-Hartmann (SH) aberrometer. Both instruments were implemented on the same optical table to facilitate interleaved measurements on the same eyes under similar experimental conditions. Variability of repeated measures of individual coefficients tended to be much greater for OA data than for SH data. Although Zernike coefficients obtained from a single measurement were generally larger when measured with the OA than with the SH, the averages across five trials were often smaller for the OA. The Zernike coefficients obtained from the two instruments were not significantly correlated. Radial modulation-transfer functions and point-spread functions derived from the two sets of measurements were similar for some subjects, but not all. When average Zernike coefficients were used to determine optical quality, the OA indicated superior optics in some eyes, but the reverse trend was true if Zernike coefficients from individual trials were used. Possible reasons for discrepancies between the OA and SH measurements include difference in sampling density, quality of data images, alignment errors, and temporal fluctuations. Multivariate statistical analysis indicated that the SH aberrometer discriminated between subjects much better than did the objective aberroscope.  相似文献   
54.
Arthroscopy has a valuable role in the treatment of elbow arthritis in the athletic population. General arthroscopicdebridement techniques used in the treatment of arthritis in other joints are quite valuable. Arthroscopic modifications of open techniques unique to the elbow, such as ulnohumeral arthroplasty, also are useful. As in other joints, the benefits of arthroscopic treatment of elbow arthritis may be temporary. Proper patient selection and attention to technical detail are critical in this population.  相似文献   
55.
Fluoranthene is a ubiquitous environmental pollutant. Althoughfluoranthene is mutagenic in bacterial and mammalian in vitrocell systems following metabolic activation by rat liver fraction,information on in vivo mutagenicity is lacking and studies ontumour initiating activity in mice are equivocal. In the presentstudy, the potential genetic hazard to man was assessed usingthe mouse bone marrow micronucleus and rat liver unscheduledDNA synthesis test systems. Fluoranthene did not show any evidenceof genotoxicity in either of the in vivo assays following acuteoral administration at levels of up to 2000 mg/kg b.w. 1To whom correspondence should be addressed  相似文献   
56.
Lifetime job histories from a population-based, case-control study were analyzed to investigate the relationship between multiple myeloma and employment in various occupations and industries. Interviews were obtained from 89% (692) of eligible incident cases and 83% (1683) of eligible controls. An elevated risk was observed among persons ever employed as painters [odds ratio (OR) + 2.1, 95% confidence interval (CI) + 1.2–3.6], particularly for those employed for 10 or more years (OR + 4.1, 95% CI + 1.8–10.4). A small excess risk was observed among agricultural workers employed for 10 or more years (OR + 1.3, 95% CI + 1.0–2.2), with a higher relative risk observed among farm laborers (OR + 1.8, 95% CI + 1.0–4.0). Among agricultural workers who reported having been highly exposed to pesticides, the OR was 5.2 (95% CI + 1.6–21.1). Some evidence, based on smaller numbers, was also found to support an association with firefighting and employment in the petroleum- and coal-products manufacturing industries. Little evidence was found to support the previously noted association with wood exposure, and no evidence for an association with employment in the rubber or petroleum refining industries was found. This study lends further support to previously reported associations between multiple myeloma and employment among painters and agricultural workers. © 1993 Wiley-Liss, Inc.  相似文献   
57.
Aneurysm of the abdominal aorta in an eighteen-month-old child   总被引:1,自引:0,他引:1  
We report the case of an infected aneurysm of the abdominal aorta in a 18 month-old child, discovered by routine palpation of the abdomen during hospitalization for pneumonia. Ultrasonography and arteriography showed a 6 cm aneurysm of the abdominal aorta beginning distal to the renal arteries which occluded the right common Iliac artery. The aneurysm was treated by interposing a 6 mm Gore-Tex graft between the infrarenal aorta and the aortic bifurcation. Pathologic examination of the aneurysmal wall demonstrated a leukocytic Infiltrate and the presence of encapsulated Gram positive organisms. Arterial aneurysms are exceedingly rare in children. Their etiology is varied: infection, connective tissue disease, trauma, inflammatory arterial disease or other rare diseases such as tuberous sclerosis, neurofibromatosis, or Beçhet’s disease.  相似文献   
58.
The effects of tetracaine (10–50 M) and ryanodine (0.1–10 M) were tested on the slow outward K+ current (I so) and the mechanical tension of isolated frog muscle fibres in a voltage-clamp device (double mannitol-gap) connected to a mechanoelectric transducer. In the concentration range tested, both drugs induced a simultaneous inhibition of tension and current. In all cases the effect on tension was twice that on current. The tetracaine-induced current and tension blocks were fully reversible and dose-dependent. In contrast the ryanodine effects on current and tension were not reversible and did not exhibit a dose dependence except for the delay before the onset of the response, which was shortened when the concentration was raised. Linear regression analysis of the time-dependent and dose-dependent effects of both drugs indicated a strong correlation between the decreases in tension and current. It is concluded that the slow outward current is partly under the control of the Ca2+ release from sarcoplasmic reticulum during contraction.  相似文献   
59.
Summary We report a case of a third ventricular neuroblastoma (neurocytoma) in a 66 year old man. A stereotactic needly biopsy was performed to obtain a tissue diagnosis and was followed by total resection. We elected not to give radiation or chemotherapy and to follow the patient closely with serial CT scans. Presently, 48 months postoperatively, the patient is free of tumor by head CT scan and able to live independently. We reviewed the literature of primary cerebral neuroblastomas/neurocytomas occurring in adults (15 years of age) and found 32 cases. Our patient is the oldest of this group with a mean age of 32 ± 14 years (S.D.). The location of the 33 neoplasms was intraventricular in 17 cases (52%) and intraparenchymal in 16 cases. The male to female ratio was 2: 1. Of the 17 patients having a minimal follow-up period of 5 months (mean 51 months), five developed recurrences after 5 to 144 months (mean 50 months) compared to 12 patients without recurrence after a 6- to 72-month follow-up period (mean 52 months). Recurrences occurred statistically significantly more often in parenchymal neuroblastomas/neurocytomas than in intraventricular tumor locations.  相似文献   
60.
The last decade has been characterised by the development of several anticoagulation methods as alternatives to the heparins. One of these is the antithrombin hirudin, which is now available on a large scale in the recombinant form. The application of hirudin as an anticoagulant in haemodialysis has been complicated by the decrease of its clearance in patients with renal failure. The half-life of hirudin is more than 30 times longer in haemodialysis patients than in healthy subjects. Therefore, at present, its use in the haemodialysis setting is essentially limited to heparin-induced thrombocytopenia (HIT). Hirudin has been used sporadically and with success in nonrenal failure patients with HIT and at least once on a regular basis in a haemodialysis patient. A starting dose between 0.08 and 0.15 mg/kg for the first dialysis, followed by 50% of this quantity during the following dialyses is recommended. Hirudin activity can be monitored by aiming for threshold activated partial thromboplastin time (aPTT) values between 60 and 90 seconds, with urgent dosage adaptations once aPTT rises above 100 to 120 seconds. Hirudin concentrations during dialysis should be maintained between 400 and 1000 microg/L, with determination by ecarin clotting time or chromogenic assays. At present, the use of hirudin is also limited by the absence of an effective antidote. In studies in humans, no enhanced removal of hirudin was observed during dialysis with large pore dialysers in contrast to earlier published animal studies.  相似文献   
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