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51.
52.
We performed semistructured interviews with 30 family members of patients with advanced dementia to identify the factors that facilitate or hinder advance planning by persons with dementia. All interviews were analyzed using qualitative data analysis techniques. The majority (77%) of family members reported that their relative had some form of written advance directive, and at least half reported previous discussions about health care preferences (57%), living situation or placement issues (50%), and finances or estate planning (60%) with the patient. Family members reported some themes that prompted planning and others that were barriers to planning. Events that most often triggered planning were medical, living situation, or financial issues associated with a friend or family member of the patient (57%). Barriers to planning included both passive and active avoidance. The most common form of passive avoidance was not realizing the importance of planning until it was too late to have the discussion (63%). The most common form of active avoidance was avoiding the discussion (53%). These data suggest potentially remediable strategies to address barriers to advance planning discussions.  相似文献   
53.
合成了15个3α和β-取代苯申酰氨基-6β-羟基,乙酰氧基和苯甲酰氧基-托品烷类化合物。其中化合物5d,12c和12d对D-1和D-2受体都有一定的亲和作用。  相似文献   
54.
OBJECTIVE: The objective of this study was to identify what standard of decision making a family member uses when making medical decisions for their relative with advanced dementia. METHODS: Thirty family members of patients with advanced dementia from an Alzheimer disease center and a suburban long-term care facility were interviewed using a semistructured interview. All interviews were audiotaped, transcribed, and analyzed using qualitative data analysis techniques. RESULTS: Family members were split almost evenly in the standard they used when making medical decisions for their relative: substituted judgment (43%) or best interests (57%). However, few who used the substituted judgment standard viewed it as distinct from best interests. Instead, both standards were taken into consideration when making medical decisions. In addition to not having discussions about healthcare preferences, the reasons for not using a substituted judgment included: the need for family consensus, unrealistic expectations of the patient, the need to incorporate their relative's quality of life into the decision, and the influence of healthcare professionals. Family members who did not have discussions about healthcare preferences identified various barriers to the discussion, including waiting too long, avoiding the topic, and the patient's denial of dementia. CONCLUSION: These data suggest several reasons why surrogate decision-makers for persons with advanced dementia do not use the substituted judgment standard and the potential value of interventions that would allow patients with early-stage dementia and their family members to discuss healthcare preferences.  相似文献   
55.
The pharmacokinetics of mezlocillin were investigated in 26 patients with alcoholic liver disease. Serum concentrations of mezlocillin were measured following intravenous administration of 3 g doses over 30 min. The mean peak serum concentration (+/- standard deviation) of mezlocillin at the end of infusion was 138.8 +/- 55.7 mg/l and the mean terminal half-life (T 1/2 beta) was 2.10 +/- 0.9 h. The 24 h urinary recovery of mezlocillin was 35.4 +/- 12.4% of the administered dose. Serum clearance was found to be inversely correlated with alkaline phosphatase and with total bilirubin. The T 1/2 beta was related to the following clinical measurements: age, SGOT and prothrombin time. This relationship suggests it may be prudent to adjust the dosage and the dosage interval of mezlocillin in patients with hepatobiliary dysfunction.  相似文献   
56.
A patient with Salmonella typhi bacteremia was sucessfully treated with cefamandole, a new cephalosporin derivative. Infection has not recurred during 6 months of follow-up observation. Minimum inhibitory concentrations and minimum bactericidal concentrations of cefamandole, cephalothin, ampicillin, and chloramphenicol were compared against 26 strains of S. typhi. All the strains were susceptible to cefamandole in vitro. Seven of the strains were resistant to chloramphenicol, and another seven were resistant to both chloramphenicol and ampicillin. Cefamandole appears to warrant further clinical trial for the treatment of typhoid fever.  相似文献   
57.
Mitchell  GH; Hadley  TJ; McGinniss  MH; Klotz  FW; Miller  LH 《Blood》1986,67(5):1519-1521
Plasmodium falciparum malaria parasites with different capabilities of invading sialic acid-deficient erythrocytes were identified. Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase-treated and Tn erythrocytes twice as efficiently as Thai-2 parasites cultured in normal erythrocytes and seven to ten times more efficiently than a cloned line of Camp parasites cultured in normal erythrocytes. All three parasite lines required sialic acid for optimal invasion, but Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase- treated erythrocytes with 45% efficiency whereas Camp parasites invaded neuraminidase-treated erythrocytes with less than 10% efficiency. P falciparum malaria parasites probably possess two receptors: one that binds to a sialic acid-dependent ligand and another that binds to a sialic acid-independent ligand. Parasites may differ in the quantity or affinity of their receptors for the sialic acid-independent ligand.  相似文献   
58.
59.
Objectives. Self-rated health (SRH) is a robust predictor of subsequent health and mortality. Although age, gender, and race differences in SRH have been explored, less work has examined ethnic differences, particularly in the US.

Design. The current study uses representative data from six Chicago communities to compare levels and determinants of fair–poor health for Blacks, Whites, Mexicans, and Puerto Ricans (n=1311).

Results. Mexicans and Puerto Ricans were at least three times more likely to report fair or poor health than Whites, while African-Americans were over twice as likely. In adjusted logistic regression models, only Mexicans remain significantly more likely to report fair–poor health than Whites (OR = 4.3, CI = 1.8–9.8). However, this effect disappears when controlling for acculturation. No variable predicted poor subjective health for all groups, though depression was associated with poor health for most.

Conclusion. Together, these analyses suggest that the single item measure of SRH might not be appropriate for comparing health status across members of different race/ethnic groups. More research is needed to understand what factors influence how an individual perceives his or her health.  相似文献   

60.
Ivy  SP; Olshefski  RS; Taylor  BJ; Patel  KM; Reaman  GH 《Blood》1996,88(1):309-318
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents.  相似文献   
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