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Caregivers (n = 53) of patients with mild to moderate dementia administered a modified version of a cognitive examination at home to their patients. Comparisons between caregiver-administered examinations and the associated clinical examinations revealed a high degree of interrater reliability that was not affected by age or level of education of the caregiver. Reliable assessment of cognitive functioning by caregivers can provide clinicians with an alternative method for monitoring cognitive function of dementia patients. 相似文献
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In diagnostic radiology, the routine measurement of exposure levels for a reference patient is an important part of an effective quality assurance program. In the United States, chest radiography is the most frequent examination and has the lowest exposure level of all radiologic examinations. We estimated the amount of exposure an average patient received from both manual and automatic exposure-controlled radiographic techniques by using a "patient-equivalent" chest phantom during measurements. A densitometric procedure was used to assess processor performance. The mean exposure from 194 chest systems was 20 mR (5.16 X 10(-5) C/kg); the mean film density, 1.38; and the mean processing speed, 108. It is interesting to note that a wide range of radiographic techniques, processing conditions, and screen-film speeds are currently being used. With the information given in our study, investigators can begin to identify the problems that lead to unusual exposure levels and, perhaps, poor image quality. 相似文献
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The deleterious effects of low-dose corticosteroids on bone density in patients with polymyalgia rheumatica 总被引:4,自引:1,他引:4
Pearce G; Ryan PF; Delmas PD; Tabensky DA; Seeman E 《Rheumatology (Oxford, England)》1998,37(3):292-299
The beneficial effects of corticosteroid therapy in the treatment of
rheumatic diseases may be offset by the occurrence of corticosteroid-
related osteoporosis. This problem may be overcome by using low-dose
corticosteroids; however, the dose of corticosteroids that is both
efficacious and skeletal sparing is uncertain. Therefore, the aim of this
study was to determine whether low-dose prednisolone treatment results in
bone loss and modifies bone turnover. Nineteen patients (12 female, seven
male) suffering from polymyalgia rheumatica received 10 mg or less daily,
given in reducing dosage, with a range of 2.5-10 mg and an average of
6.0+/-0.2 mg daily (+/-S.E.M.). Prior to the commencement of therapy and at
regular intervals during treatment, bone mineral density (BMD) using dual
X-ray absorptiometry and circulating biochemical and hormonal determinants
of bone turnover were measured. The patients were followed for 14.4+/-1.6
months (range 6-27). They were compared to 19 age-matched controls. Despite
a mean exposure dose of 6 mg/day and disease remission, BMD decreased in
the patients at the lumbar spine (2.6+/-0.8%, P < 0.01), femoral neck
(2.9+/-1.5%, P=0.06), Ward's triangle (5.5+/-2.9%, P=0.06) and the
trochanter (4.3+/-1.9%, P < 0.05). Total body bone mass decreased by
50+/-19 g in the first 6 months (P < 0.02), and by 39+/-30 g in the
remaining 8 months of follow- up [not significant (NS)]. In the first 6
months, BMD decreased at the lumbar spine (1.7+/-0.9%, P = 0.06). From 6
months to the end of follow- up, BMD decreased by 8.5+/-3.5% at Ward's
triangle (P < 0.05) and by 4.8+/-2.5% at the femoral neck (P=0.08). The
fall in BMD correlated with the cumulative prednisolone dose at
trabecular-rich regions (trunk r=-0.72, P < 0.001; ribs r=-0.53, P <
0.05). Bone resorption, assessed by urinary cross-laps, was 54.7% higher
than controls before treatment was started (P < 0.05) and decreased by
23.5+/-7.1% in the first month of treatment when the mean prednisolone dose
was 9.1 mg/day, range 5-10 (P < 0.0001). Serum osteocalcin was not
suppressed by disease before treatment, decreased by 27.4+/-5.1% during the
first month of treatment (P < 0.001), remained suppressed while the
daily dose of prednisolone was > 5 mg/day, but returned to baseline
below this dose. Serum parathyroid hormone was 19.3% lower in the patients
than controls at baseline (NS), and increased by 46.1% (P < 0.05) but
was no higher than controls at any time. Muscle strength increased by
20-60% (P < 0.05 to < 0.01). Prophylaxis should be considered in
patients receiving > or = 5 mg/day prednisolone daily as bone loss is 2-
to 3-fold expected rates. Earlier trabecular bone loss may predispose to
spine and rib fracture; later cortical bone loss may predispose to hip
fractures. Doses of prednisolone of < 5 mg daily may be skeletal
sparing, but may not be efficacious.
相似文献
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Helfand SC; Modiano JF; Moore PF; Soergel SA; MacWilliams PS; Dubielzig RD; Hank JA; Gelfand EW; Sondel PM 《Blood》1995,86(2):636-645
We identified a dog with large granular lymphocytic leukemia and cutaneous lymphoma that exhibited constitutive expression of interleukin-2 (IL-2) receptors by the leukemic peripheral blood lymphocytes. The leukemic cells phenotypically resembled natural killer (NK) cells, and their surface IL-2 receptors were functional, as determined by the capacity to bind human recombinant IL-2 with high- affinity resulting in the transduction of proliferation signals and in the development of lymphokine-activated killer cell activity. These cells produced IL-2 spontaneously, and they may have maintained their proliferative state through an IL-2-dependent autocrine growth pathway. Our results indicate that neoplastic lymphocytes of syndromes that involve circulating leukemic cells with dermotropism can originate from NK-like cells. Additionally, the data also suggest that proliferative conditions such as these may be the result of the aberrant production of IL-2. Further, this case illustrates the potential for the use of hematopoietic malignancies in the dog as a suitable animal model for immune targeting of IL-2 receptors as a novel treatment approach for similar malignancies of human beings. 相似文献