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101.
102.
The current study examines several indicators of dementia severity and their relationship to anticipatory grief (AG) to investigate which aspects of the caregiving situation may lead to greater levels of AG. Eighty informal dementia caregivers completed interviews and questionnaires assessing their experiences, and regression analyses were used to examine the relationship between primary stressors (disease stage, hours of weekly care, ADL and IADL impairments and behavior problems) and AG. Results revealed that behavior problems were the only variable which was significantly associated with AG, and follow-up analyses revealed that adult child and spouse caregivers responded differently to different types of behavior problems. Overall, the grief experiences of dementia caregivers appear to be more strongly related to behavioral problems than other indicators of disease severity. 相似文献
103.
Increased sensitivity to etomidate in the elderly: initial distribution versus altered brain response 总被引:8,自引:0,他引:8
To determine the effect of aging on the pharmacokinetics and pharmacodynamics of etomidate, we administered etomidate (5 to 10 mg/min) by intravenous infusion to 21 healthy surgical patients, age 22 to 82 yr. Etomidate produced progressive slowing of the EEG to an easily recognized pattern (stage 3) that determined the dosage endpoint. Subsequent power-spectrum analysis of the EEG gave the median frequency. Median frequency values and simultaneous measurements of blood etomidate concentration were incorporated into a sigmoid Emax pharmacodynamic model that permitted an estimate of IC50, the blood etomidate concentration which produced a 50% reduction in the median frequency. The dose of etomidate required to reach the uniform EEG endpoint decreased significantly with increasing age (r2 = .68) as did the dose needed to produce maximal median frequency depression (r2 = .69). None of the parameters of the pharmacodynamic effect model, including IC50, correlated with age, suggesting that increased brain sensitivity in the elderly does not cause the age-related change in dose requirement. The initial distribution volume for etomidate decreased significantly with increasing age (r = .56), implying that a higher initial blood concentration in the elderly following any given dose of etomidate is part of the cause of the lower dose requirement in the elderly patient. A contracted initial distribution volume in the elderly may result from well described physiologic changes of age. Etomidate clearance also decreased with age. Age-dependent changes in etomidate pharmacokinetics rather than altered brain responsiveness may be the basis for the decreased etomidate dose requirement in the elderly. 相似文献
104.
The elderly comprise an increasing proportion of chronic dialysis patients. Recruiting them for continuous peritoneal dialysis (CPD) would help CPD programs maintain a patient population. We retrospectively studied the ability of a prospective evaluation to predict success with CPD in elderly (age greater than 60 years) patients. PD nurses and a renal social worker assigned scores in 10 categories, which were then averaged to obtain an over-all evaluation score. Scores were from 1-5 with 1 = good, 5 = poor, and 3 = average. Thirty-four elderly patients began CPD during the study period. Evaluation scores were available for 28 of these patients before they began dialysis. Evaluation scores less than 3 predicted success with CPD (2.2 +/- 0.2 versus 3.2 +/- 0.4 in patients transferring to hemodialysis, p less than 0.02). Patient motivation and preference were the categories that predicted success with CPD. Elderly patients were more likely than younger patients (those less than 60 years of age) to decline CPD for social reasons (46% versus 4% respectively, p less than 0.001). Elderly patients required more CPD training time than young patients (4.9 +/- 0.7 days versus 3.3 +/- 0.8 days respectively, p less than 0.01). We conclude that a prospective assessment of elderly patients can predict success with CPD and provide information important to individual structuring of CPD training and follow-up. 相似文献
105.
This study contributes a Canadian perspective to a growing body of international studies examining suicide among cohorts
of suicide attempters, and a much more limited literature on the epidemiology of suicide in Canada. We evaluated the 13-year
mortality experience of a regional cohort of 876 first-ever inpatient hospital admissions for a suicide attempt admitted between
1979 and 1981. Compared to the general population, study subjects were 4 times more likely to die of any cause, but 25 times
more likely to commit suicide and 15 times more likely to die of accidental or adverse causes. Ten years after then first
hospitalization for attempted suicide, 5.9% of study subjects had commited suicide. Baseline age appeared to be a risk factor
for women, but not for men. Women under 60 years had the best 10-year survival (3.6% had commited suicide) and women over
60 years had the poorest (17.5%). A total of 8.7% of men under 60 years and 10% of those over 60 years commited suicide within
10 years. The remainder of the analysis focused on those under 60 years of age at the time of their index inpatient hospitalization.
Three factors were prognostic for suicide: being male, which had a relative risk (RR) of 5.0, living in a lower income area
(RR = 3.2), and having used a violent method during the index attempt (RR = 2.5). The periods of greatest risk for suicide
were within the 1st and 4th years following first-ever inpatient hospitalization, with the 4th year representing the time
of highest risk. The identification of time periods subsequent to first-ever hospitalization when patients are at greatest
risk of suicide can be used to guide the timing and duration of clinical interventions and aftercare to ensure that patients
are appropriately supported during periods of highest risk.
Accepted: 11 May 1998 相似文献
106.
Perceptive properties of the multi-site electrical microstimulation of the olfactory bulb in the rat
Electrical microstimulation of the olfactory bulb in different locations has been shown to provide water-deprived rats with discriminative cues for selecting a palatable solution without tasting it in a two-choice test. Some perceptive properties of bulbar electrical stimulation were investigated. It was shown that the perceptive effect evoked by stimulating a given site could be recognized when this site was stimulated together with several others. The animals' perception of multi-site stimulation patterns seems therefore to be analytical rather than synthetic. Discrimination of stimulation patterns did not require presentation of concurrent patterns inside a short time interval. Identification of a multi-site pattern was possible when this pattern was presented alone in a test session. Individual characteristics of bulbar microstimulation appear to be perceived absolutely rather than differentially. A good retention of the discrimination learning of specific stimulation patterns was observed. Animals could identify stimulation patterns after complete interruption of the training for 17 days. The results are discussed with reference to the properties of the natural stimulation of the olfactory system. 相似文献
107.
Approximately 2154 regional blood centers and hospital-based blood banks and transfusion services responded to the 1991 American Association of Blood Banks Institutional Membership Questionnaire that elicited data from 1990. Information from 2144 institutions was considered valid. Questionnaire topics were donor blood collections, hemapheresis, perioperative cell salvage, component usage, and transfusion-associated diseases. Institutional members reported collecting 9.3 million units, of which 90.9 percent were for allogeneic use in the community, 6.0 percent were for autologous use, and 3.1 percent were directed donations. The percentage of directed-donor units that were crossed over for allogeneic use (51%) was greater than the percentage of units transfused to the designated patient (49%). Only 12.5 percent of institutions reported obtaining specific consent for transfusion. Of the 15.4 million transfused blood components, 8.5 million were red cells, 4.1 million were platelets, 1.8 million were fresh-frozen plasma, and 0.9 million were cryoprecipitate. There were 1263 reported cases of transfusion-associated hepatitis. Approximately 44 percent of the patients who were tested proved positive for hepatitis B surface antigen, and 80 percent of the patients who were tested proved positive for antibody to hepatitis C. The questionnaire's aggregate results can be used to assess current patterns of blood donation and transfusion activities. 相似文献
108.
Summary Two monoclonal antibodies, SC1 and SC2, were raisedin vitro against antigens from the stereocilia of guinea-pig hair cells. They both labelled stereociliary antigens that were not detected in any other cell within the cochlear duct or the vestibular epithelia. SC1 cross-reacted with the tectorial membrane in the cochlea and labelled both cochlear and vestibular hair cells from both the mouse and the rat. In the mouse the SC1 antigen was labelled from embryonic days 16–18, coincident with the development of the stereociliary bundles. SC1 cross-reacted with neuromuscular junctions from striated muscle and with basal keratinocytes in skin. SC2 did not cross-react cleanly with hair cells from the mouse or the rat but it cross-reacted with proximal tubules of the guinea-pig kidney. Both antibodies can be used as cellular markers within the guinea-pig cochlea and SC1 should be particularly useful for studies of hair cell differentiation in the mouse. 相似文献
109.
Either a simple balanced salt solution (BSS) or a bicarbonate-buffered, glutathione-containing commercial irrigant (BSS Plus, Alcon Laboratories, Fort Worth, Texas, U.S.A.) may be used during the vitrectomy portion of a corneal transplant procedure. To simulate the conditions present in the anterior chamber during the first few hours after vitrectomy and grafting, we performed in vitro perfusions of stored human corneas using each irrigant and measured corneal thickness over a 3-hour period. Irrespective of the preservation medium used (McCarey Kaufman, Chondroin Sulfate or Dexsol, all from Chiron Ophthalmics, Irvine, California) or duration of storage (2 or 4 days), corneas irrigated with BSS Plus exhibited significantly (p less than .05) decreased thickness compared with their paired mates irrigated with BSS. In ultrastructural studies performed on postperfusion corneas, there was a tendency toward improved surface morphology in the in vitro BSS Plus-perfused tissue. This study shows that in vitro corneal thickness after preservation is significantly irrigant dependent, with BSS Plus providing the essential ingredients to promote the corneal endothelial pump function. 相似文献
110.