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991.
STUDY OBJECTIVE: Elderly emergency department patients have complex medical needs and limited social support. A transitional model of care adapted from hospitals was tested for its effectiveness in the ED in reducing subsequent service use. METHODS: A randomized clinical trial was conducted at 2 urban, academically affiliated hospitals. Participants were 650 community-residing individuals 65 years or older who were discharged home after an ED visit. Main outcomes were service use rates, defined as repeat ED visits, hospitalizations, or nursing home admissions, and health care costs at 30 and 120 days. Intervention consisted of comprehensive geriatric assessment in the ED by an advanced practice nurse and subsequent referral to a community or social agency, primary care provider, and/or geriatric clinic for unmet health, social, and medical needs. Control group participants received usual and customary ED care. RESULTS: The intervention had no effect on overall service use rates at 30 or 120 days. However, the intervention was effective in lowering nursing home admissions at 30 days (0.7% versus 3%; odds ratio 0.21; 95% confidence interval [CI] 0.05 to 0.99) and in increasing patient satisfaction with ED discharge care (3.41 versus 3.03; mean difference 0.37; 95% CI 0.13 to 0.62). The intervention was more effective for high-risk than low-risk elders. CONCLUSION: An ED-based transitional model of care reduced subsequent nursing home admissions but did not decrease overall service use for older ED patients. Further studies are needed to determine the best models of care for this setting and for at-risk patients.  相似文献   
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Glycoprotein (GP) IIb/IIIa antagonists are effective therapeutic agents, but elicit thrombocytopenia with a frequency that approaches 2%. Here, we provide evidence that thrombocytopenia in humans treated with the GP IIb/IIIa antagonist roxifiban is immune mediated. Two patients underwent conversion to a highly positive drug-dependent antibody (DDAB) status temporally associated with thrombocytopenia. Despite the continued presence of DDABs, the fall in platelet count was reversed by discontinuation of drug treatment, pointing to the exquisite drug dependency of the immune response. DDABs appear to bind to neoepitopes in GP IIb/IIIa elicited on antagonist binding. This information was used to develop an enzyme-linked immunosorbent assay (ELISA) for DDAB using solid-phase GP IIb/IIIa. A high level of specificity is indicated by the observation that DDAB binding is dependent on the chemical structure of the GP IIb/IIIa antagonist and that only 2% to 5% of human blood donors and 5% of chimpanzees present with pre-existing DDABs. Furthermore, none of 108 nonthrombocytopenic patients from the phase II roxifiban study showed an increase in antibody titer. Absorption of thrombocytopenia plasma with platelets reduced the DDAB ELISA signal, indicating that the test detects physiologically relevant antibodies. Screening patients for pre-existing or increasing DDAB titer during treatment with GP IIb/IIIa antagonists may reduce the incidence of drug-induced thrombocytopenia.  相似文献   
996.
OBJECTIVES: To describe the prevalence of, timing of, and factors associated with decisions not to hospitalize nursing home residents with advanced dementia who were dying. DESIGN: Retrospective cohort study. SETTING: Six hundred seventy five-bed nursing facility in Boston. PARTICIPANTS: Two hundred forty residents in a teaching nursing home who died between January 2001 and December 2003 with advanced dementia. MEASUREMENTS: The prevalence and timing of do-not-hospitalize (DNH) orders were determined from the medical record. Data describing demographic characteristics, health conditions, advance care planning, sentinel events, and health services usage during the last 6 months of life were examined. Factors associated with having a DNH order were identified. RESULTS: At the time of death, 83.8% of subjects had a DNH order. The prevalence of DNH orders was 50.0% and 34.4%, 30 and 180 days before death, respectively. Hospital transfers were common during the last 6 months of life (24.6%). Factors independently associated with having a DNH order before death included surrogate decision-maker was not the subject's child (adjusted odds ratio (AOR)=4.39, 95% confidence interval (CI)=1.52-12.66), eating problems (AOR=4.17, 95% CI=1.52-11.47), aged 92 and older (AOR=2.78, 95% CI=1.29-5.96), and length of stay 2 years or longer (AOR=2.34, 95% CI=1.11-4.93). CONCLUSION: For most institutionalized persons with advanced dementia, a decision to forgo hospitalization is not made until death is imminent. Thus, hospital transfers are common near the end of life. The finding that DNH orders are associated with patient and surrogate factors can help clinicians identify cases in which decisions to forgo hospitalizations may be facilitated.  相似文献   
997.
Prions are infectious protein conformations that are generally ordered protein aggregates. In the absence of prions, newly synthesized molecules of these same proteins usually maintain a conventional soluble conformation. However, prions occasionally arise even without a homologous prion template. The conformational switch that results in the de novo appearance of yeast prions with glutamine/aspargine (Q/N)-rich prion domains (e.g., [PSI+]), is promoted by heterologous prions with a similar domain (e.g., [RNQ+], also known as [PIN+]), or by overexpression of proteins with prion-like Q-, N-, or Q/N-rich domains. This finding led to the hypothesis that aggregates of heterologous proteins provide an imperfect template on which the new prion is seeded. Indeed, we show that newly forming Sup35 and preexisting Rnq1 aggregates always colocalize when [PSI+] appearance is facilitated by the [RNQ+] prion, and that Rnq1 fibers enhance the in vitro formation of fibers by the prion domain of Sup35 (NM). The proteins do not however form mixed, interdigitated aggregates. We also demonstrate that aggregating variants of the polyQ-containing domain of huntingtin promote the de novo conversion of Sup35 into [PSI+]; whereas nonaggregating variants of huntingtin and aggregates of non-polyQ amyloidogenic proteins, transthyretin, alpha-synuclein, and synphilin do not. Furthermore, transthyretin and alpha-synuclein amyloids do not facilitate NM aggregation in vitro, even though in [PSI+] cells NM and transthyretin aggregates also occasionally colocalize. Our data, especially the in vitro reproduction of the highly specific heterologous seeding effect, provide strong support for the hypothesis of cross-seeding in the spontaneous initiation of prion states.  相似文献   
998.
Background  Although previous studies suggest an association between provider burnout and suboptimal self-reported communication, no studies relate physician burnout to observed patient-physician communication behaviors. Objective  To investigate the relationship between physician burnout and observed patient-physician communication outcomes in patient-physician encounters. Design  Longitudinal study of enrollment data from a trial of interventions to improve patient adherence to hypertension treatment. Setting  Fifteen urban community-based clinics in Baltimore, MD. Participants  Forty physicians and 235 of their adult hypertensive patients, with oversampling of ethnic minorities and poor persons. Fifty-three percent of physicians were women, and the average practice experience was 11.2 years. Among the 235 patients, 66% were women, 60% were African-American, and 90% were insured. Measurements  Audiotape analysis of communication during outpatient encounters (one per patient) using the Roter Interaction Analysis System and patients’ ratings of satisfaction with and trust and confidence in the physician. Results  The median time between the physician burnout assessment and the patient encounter was 15.1 months (range 5.6–30). Multivariate analyses revealed no significant differences in physician communication based on physician burnout. However, compared with patients of low-burnout physicians, patients of high-burnout physicians gave twice as many negative rapport-building statements (incident risk ratio 2.06, 95% CI 1.58 – 2.86, p < 0.001). Physician burnout was not significantly associated with physician or patient affect, patient-centeredness, verbal dominance, or length of the encounter. Physician burnout was also not significantly associated with patients’ ratings of their satisfaction, confidence, or trust. Conclusions  Physician burnout was not associated with physician communication behaviors nor with most measures of patient-centered communication. However, patients engaged in more rapport-building behaviors. These findings suggest a complex relationship between physician burnout and patient-physician communication, which should be investigated and linked to patient outcomes in future research.  相似文献   
999.
In humans, structural and functional changes attributable to aging are more visibly evident in the skin than in any other organ. Estrogens have significant effects on skin physiology and modulate epidermal keratinocytes, dermal fibroblasts and melanocytes, in addition to skin appendages including the hair follicle and the sebaceous gland. Importantly, skin aging can be significantly delayed by the administration of estrogen. This paper reviews the effects of estrogens on skin and the mechanisms by which estrogens can alleviate the changes due to aging that occur in human skin. The relevance of estrogen replacement therapy (HRT) in post-menopausal women and the potential value of selective estrogen receptor modulators (SERMs) as a therapy for diminishing skin aging are also highlighted.  相似文献   
1000.
We hypothesized that possession of either of 2 functional coagulation factor XIII polymorphisms, one within subunit A (Val34Leu) and one within subunit B (His95Arg), might modulate the prothrombotic effects of estrogen and help to explain the variation in incidence of arterial thrombotic events among postmenopausal women using hormone replacement therapy. In a population-based case-control study of 955 postmenopausal women, we assessed the associations of factor XIII genotypes and their interactions with estrogen therapy on risk of nonfatal myocardial infarction (MI). The presence of the factor XIIIA Leu34 allele was associated with a reduced risk of MI (odds ratio [OR] = 0.70, 95% confidence interval [95% CI] = 0.51-0.95). The presence of the factor XIIIB Arg95 allele had little association with MI risk. Neither factor XIII polymorphism alone significantly modified the association between the risk of MI and current estrogen use. In exploratory analyses, however, there was a significant factor XIII subunit gene-gene interaction. Compared to women homozygous for both common factor XIII alleles, the Arg95 variant was associated with a reduced risk of MI in the presence of the Leu34 variant (OR = 0.36, 95% CI = 0.17-0.75) but not in the absence of the Leu34 variant (OR = 1.11, 95% CI = 0.69-1.79). Moreover, among women who had at least 2 copies of the variant factor XIII alleles and were current estrogen users, the risk of MI was reduced by 70% relative to estrogen nonusers with fewer than 2 factor XIII variant alleles (P value for interaction =.03). If confirmed, these findings may permit a better assessment of the cardiovascular risks and benefits associated with postmenopausal estrogen therapy.  相似文献   
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