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71.
Robert J. Buchanan PhD ; Jane Bolin RN JD PhD ; Suojin Wang PhD ; Li Zhu PhD ; MyungSuk Kim MS 《The Journal of rural health》2004,20(2):131-135
CONTEXT: Advance directives promote patient autonomy and encourage greater awareness of final care options while reducing physician and family uncertainty regarding patient preferences. PURPOSE: To investigate differences in decision making authority and the use of advance directives among nursing home residents admitted from urban and rural areas. METHODS: A total of 551,208 admission assessments in the Minimum Data Set were analyzed for all residents admitted to a nursing facility in 2001. Using the Rural Urban Commuting Areas (RUCA) methodology and ZIP code of primary residence before admission, these residents were classified into 4 urban/rural areas. FINDINGS: Residents from rural areas were significantly more likely to have executed a durable power of attorney for health care or for financial decisions than residents admitted from the other areas, with the largest differences observed between residents admitted from urban and rural areas. Almost 6 residents in 10 from urban areas had no advance directives in place at admission compared with only 4 residents in 10 admitted from rural areas. CONCLUSIONS: Health providers and social workers in both rural and urban areas should advise patients about the value of advance directives. 相似文献
72.
73.
Mann BG Buchanan M Collins PJ Lichtenstein M 《The Australian and New Zealand journal of surgery》2000,70(11):786-790
BACKGROUND: Sentinel lymph node biopsy (SLNB) is being investigated as an alternative to formal axillary dissection in early breast cancer. Avoiding the morbidity of unnecessary axillary dissection is seen as the main potential benefit of SLNB. Sentinel lymph node biopsy also allows enhanced pathological analysis. A series of 62 sentinel node (SN) biopsies demonstrating a high incidence of micrometastases is presented here. METHODS: All SN were initially examined and reported by H&E staining. All negative SN were analysed after staining with polyclonal anticytokeratin antibody. RESULTS: Sixty-two patients underwent SLNB at Royal Melbourne Hospital between May 1998 and February 2000. One or more SN was identified in 51/62 patients. A total of 10/51 contained metastases identified after H&E staining. There was one false negative. A total of 10/41 patients with H&E-negative SN had micrometastases identified on immunohistochemistry (IHC). Micrometastases were more common in patients with larger tumours, with disease found in the H&E-negative SN of 1/17 T1a and T1b (1-10 mm), 4/15 T1c (11-20 mm), and 5/9 T2 (20-50 mm) tumours. CONCLUSION: Sentinel lymph node biopsy can accurately assess the axilla in most patients with early breast cancer. A significant proportion of histologically negative SN will have micrometastases identifiable with IHC. Although the clinical significance of such metastases is uncertain, the available evidence suggests that these patients have a poorer prognosis than other patients with negative lymph nodes. 相似文献
74.
Katharine Dunlop Lindsay W. Victoria Jonathan Downar Faith M. Gunning Conor Liston 《Neuropsychopharmacology》2021,46(5):911
Multiple structural and functional neuroimaging measures vary over the course of the lifespan and can be used to predict chronological age. Accelerated brain aging, as quantified by deviations in the MRI-based predicted age with respect to chronological age, is associated with risk for neurodegenerative conditions, bipolar disorder, and mortality. Whether age-related changes in resting-state functional connectivity are accelerated in major depressive disorder (MDD) is unknown, and, if so, it is unclear if these changes contribute to specific cognitive weaknesses that often occur in MDD. Here, we delineated age-related functional connectivity changes in a large sample of normal control subjects and tested whether brain aging is accelerated in MDD. Furthermore, we tested whether accelerated brain aging predicts individual differences in cognitive function. We trained a support vector regression model predicting age using resting-state functional connectivity in 710 healthy adults aged 18–89. We applied this model trained on normal aging subjects to a sample of actively depressed MDD participants (n = 109). The difference between predicted brain age and chronological age was 2.11 years greater (p = 0.015) in MDD patients compared to control participants. An older MDD brain age was significantly associated with increased impulsivity and, in males, increased depressive severity. Unexpectedly, accelerated brain aging was also associated with increased placebo response in a sham-controlled trial of high-frequency repetitive transcranial magnetic stimulation targeting the dorsomedial prefrontal cortex. Our results indicate that MDD is associated with accelerated brain aging, and that accelerated aging is selectively associated with greater impulsivity and depression severity.Subject terms: Depression, Cognitive ageing 相似文献
75.
Severe hemorrhage in a patient with gray platelet syndrome 总被引:2,自引:0,他引:2
76.
Vesely S Buchanan GR Cohen A Raskob G George J 《Journal of pediatric hematology/oncology》2000,22(1):55-61
PURPOSE: To assess current physician self-reported practices regarding initial management of childhood idiopathic thrombocytopenic purpura (ITP) and to determine physician self-reported willingness to participate in randomized clinical trials comparing different initial management strategies. PATIENTS AND METHODS: A questionnaire was mailed in November 1997 to all 720 members of the American Society of Pediatric Hematology/Oncology asking how they would diagnose and manage ITP in children 18 months, 5 years, and 15 years of age who were experiencing either dry purpura (cutaneous hemorrhage only) or wet purpura (active mucous membrane hemorrhage). Specific questions dealt with bone marrow aspiration, hospital admittance, treatment strategy, and specific doses of corticosteroids and intravenous immunoglobulin. RESULTS: The response rate to the questionnaire was 57%. Most respondents indicated they usually perform a bone marrow aspirate when corticosteroids are to be prescribed and administer drug therapy to patients with newly diagnosed ITP with wet or dry purpura. Only 16% of respondents would administer no drug therapy to a child with dry purpura. Intravenous immunoglobulin (IVIG) was preferred to steroids, with anti-D immunoglobulin prescribed less frequently. Hospital admittance often was used for patients with dry purpura and usually recommended for patients with wet purpura. Most respondents expressed willingness to randomize patients with dry purpura to IVIG versus no therapy and those with wet purpura to IVIG versus prednisone as part of a randomized controlled clinical trial. CONCLUSIONS: The self-reported care of the patient with ITP was influenced by the severity of presentation (dry versus wet purpura). Most physicians reported they would administer specific drug treatment in both scenarios. This survey illustrates the diverse diagnostic and management strategies currently used in childhood ITP. Because no one therapeutic approach is predominant and a scientific basis for decision making in childhood ITP has not been developed, future randomized trials are warranted. On the basis of these survey results, such trials are desired by most pediatric hematology/oncology specialists. 相似文献
77.
We evaluated the timing and pattern of changes in the complete blood cell count that preceded marrow recovery during 107 consecutive episodes of fever and neutropenia in 64 children with cancer. Four measures derived from serial daily measurement of the complete blood cell count were evaluated: total leukocyte count, absolute neutrophil count, absolute phagocyte count, and platelet count. During 70 (65%) of these 107 episodes, patients were discharged with an absolute neutrophil count of fewer than 500 cells/mm3; 24 patients were discharged from the hospital despite an absolute neutrophil count of fewer than 100 cells/mm3. During all but one of these 70 episodes, however, signs of early marrow recovery were present before discharge; sustained increases were observed in these patients' leukocyte, absolute neutrophil, absolute phagocyte, and platelet counts 2 or more days before their discharge in 41%, 49%, 50%, and 39% of cases, respectively. Although they were neutropenic at discharge, most patients had signs of multilineage marrow recovery at that time; 59 of 70 had increases in three of four of the measurements that we studied. None of the 69 patients who had evidence of marrow recovery at discharge had recurrence of fever. We conclude that children with cancer who were hospitalized for fever during periods of neutropenia have increases in the peripheral blood cell count that herald imminent bone marrow recovery, often several days before the absolute neutrophil count recovers to 500 cells/mm3. Our success in discharging such patients before resolution of neutropenia suggests that further controlled trials are needed to evaluate the safety and feasibility of cessation of antibiotic therapy and early discharge from the hospital. 相似文献
78.
79.
J. Tyler Faith Todd A. Surovell 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(49):20641-20645
The late Pleistocene witnessed the extinction of 35 genera of North American mammals. The last appearance dates of 16 of these genera securely fall between 12,000 and 10,000 radiocarbon years ago (≈13,800–11,400 calendar years B.P.), although whether the absence of fossil occurrences for the remaining 19 genera from this time interval is the result of sampling error or temporally staggered extinctions is unclear. Analysis of the chronology of extinctions suggests that sampling error can explain the absence of terminal Pleistocene last appearance dates for the remaining 19 genera. The extinction chronology of North American Pleistocene mammals therefore can be characterized as a synchronous event that took place 12,000–10,000 radiocarbon years B.P. Results favor an extinction mechanism that is capable of wiping out up to 35 genera across a continent in a geologic instant. 相似文献
80.
Jie Shang Jeanette C. Reece Daniel D. Buchanan Graham G. Giles Jane C. Figueiredo Graham Casey Steven Gallinger Stephen N. Thibodeau Noralane M. Lindor Polly A. Newcomb John D. Potter John A. Baron John L. Hopper Mark A. Jenkins Aung Ko Win 《International journal of colorectal disease》2016,31(8):1451-1457