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71.
BACKGROUND: Stable mixed donor/host hematopoietic chimerism was almost uniformly achieved in dogs given 200 cGy total body irradiation (TBI) before, and a short course of immunosuppression after, transplantation of marrow from dog leukocyte antigen-identical littermates, but was transient when the TBI dose was decreased to 100 cGy. Here, we examined whether stable engraftment could be achieved in five dogs given FTY720 (days -5 and -4), followed by 100 cGy TBI, dog leukocyte antigen-identical marrow grafts, and mycophenolate mofetil/cyclosporine. RESULTS AND CONCLUSIONS: Although all five dogs showed initial engraftment, four dogs rejected their grafts within 11 weeks, whereas one dog was euthanized on day 17 due to enteritis. This was not different from the control dogs not given FTY720 (P=0.32). Thus, FTY720 failed to enhance allogeneic engraftment in this model, perhaps due to in vivo T-cell depletion of the graft resulting from sequestration of donor lymphocytes in host central lymphoid tissues.  相似文献   
72.
Repair of bone allograft fracture using bone morphogenetic protein-2   总被引:7,自引:0,他引:7  
Long-term clinical data have shown that reconstruction using bone allografts provide adequate function after extensive tumor surgery. Complications such as nonunion of allograft-host interface, infection, and allograft fracture often require major revision surgeries. Allograft fractures usually do not induce the same repair process that is seen in normal fracture healing. The authors did an experimental study to test whether bone morphogenetic protein-2 can induce and achieve osseous repair in an allograft osteotomy model. Recombinant human bone morphogenetic protein-2 was applied at femoral intercalary allograft osteotomy sites in 20 rats. Forty additional rats served as controls (carrier alone and sham). Specimens in all groups were examined histologically and radiographically at 4 and 8 weeks. Specimens in the control groups showed only fibrosis by 8 weeks. In contrast, none of 10 specimens in the experimental group showed radiographic union at 8 weeks. New bone formation and integration with underlying allografts were seen in the experimental group as early as 4 weeks. These data suggest that fracture repair in the allograft bone can be triggered by a biologic regulator that is expressed during normal fracture healing.  相似文献   
73.
A district-based audit of maternal and perinatal mortality began during 1994 in three provinces of South Kalimantan, Indonesia. Both medical and non-medical factors were documented and an effort was made to progress from merely assessing substandard care to recommending improvements in access to care and the quality of care. Extensive discussions of cases of maternal death were held during regular meetings with providers, policy-makers and community members. The sources of information included verbal autopsies with family members and medical records. Between 1995 and 1999 the audit reviewed 130 maternal deaths. The leading causes of death were haemorrhage (41%) and hypertensive diseases (32%). Delays in decision-making and poor quality of care in health facilities were seen as contributory factors in 77% and 60% of the deaths, respectively. Economic constraints were believed to have contributed to 37% of the deaths. The distance between a patient's home and a health provider or facility did not appear to have a significant influence, nor did transport problems. The audit led to changes in the quality of obstetric care in the district. Its success was particularly attributable to the process of accountability of both health providers and policy-makers and to improved working relationships between health providers at different levels and between providers and the community. With a view to the continuation and further expansion of the audit it may be necessary to reconsider the role of the provincial team, the need of health providers for confidentiality, the added benefit of facility-based audits, the need to incorporate scientific evidence into the review process, and the possible consideration of severe complications as well as deaths. It may also be necessary to recognize that village midwives are not solely responsible for maternal deaths.  相似文献   
74.
Context  Quality of care of patients with acute myocardial infarction (AMI) has received intense attention. However, it is unknown if a structured initiative for improving care of patients with AMI can be effectively implemented at a wide variety of hospitals. Objective  To measure the effects of a quality improvement project on adherence to evidence-based therapies for patients with AMI. Design and Setting  The Guidelines Applied in Practice (GAP) quality improvement project, which consisted of baseline measurement, implementation of improvement strategies, and remeasurement, in 10 acute-care hospitals in southeast Michigan. Patients  A random sample of Medicare and non-Medicare patients at baseline (July 1998–June 1999; n = 735) and following intervention (September 1–December 15, 2000; n = 914) admitted at the 10 study centers for treatment of confirmed AMI. A random sample of Medicare patients at baseline (January–December 1998; n = 513) and at remeasurement (March–August 2001; n = 388) admitted to 11 hospitals that volunteered, but were not selected, served as a control group. Intervention  The GAP project consisted of a kickoff presentation; creation of customized, guideline-oriented tools designed to facilitate adherence to key quality indicators; identification and assignment of local physician and nurse opinion leaders; grand rounds site visits; and premeasurement and postmeasurement of quality indicators. Main Outcome Measures  Differences in adherence to quality indicators (use of aspirin, -blockers, and angiotensin-converting enzyme [ACE] inhibitors at discharge; time to reperfusion; smoking cessation and diet counseling; and cholesterol assessment and treatment) in ideal patients, compared between baseline and postintervention samples and among Medicare patients in GAP hospitals and the control group. Results  Increases in adherence to key treatments were seen in the administration of aspirin (81% vs 87%; P = .02) and -blockers (65% vs 74%; P = .04) on admission and use of aspirin (84% vs 92%; P = .002) and smoking cessation counseling (53% vs 65%; P = .02) at discharge. For most of the other indicators, nonsignificant but favorable trends toward improvement in adherence to treatment goals were observed. Compared with the control group, Medicare patients in GAP hospitals showed a significant increase in the use of aspirin at discharge (5% vs 10%; P<.001). Use of aspirin on admission, ACE inhibitors at discharge, and documentation of smoking cessation also showed a trend for greater improvement among GAP hospitals compared with control hospitals, although none of these were statistically significant. Evidence of tool use noted during chart review was associated with a very high level of adherence to most quality indicators. Conclusions  Implementation of guideline-based tools for AMI may facilitate quality improvement among a variety of institutions, patients, and caregivers. This initial project provides a foundation for future initiatives aimed at quality improvement.   相似文献   
75.
Postmenopausal estrogen and progestin use in relation to breast cancer risk.   总被引:13,自引:0,他引:13  
Epidemiological evidence now consistently supports a modest increase in breast cancer risk among women using postmenopausal hormones, usually estrogens.Less is known regarding how the addition of progestin affects breast cancer risk. The objective of this study was to investigate the type and duration of postmenopausal therapy and breast cancer risk. We performed a multicenter population-based case-control study set in Massachusetts, New Hampshire, and Wisconsin. The subjects were 5298 postmenopausal women (age range, 50-79 years) with a new diagnosis of invasive breast cancer from statewide tumor registries. For comparison, 5571 controls were randomly selected from population lists. Participants completed a structured telephone interview covering hormone use and breast cancer risk factors. Multivariable regression models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs). The RR for breast cancer increased with longer durations of hormone use, about 2%/year for estrogen alone (RR, 1.02; 95% CI, 1.01-1.03) and 4%/year for estrogen-progestin use (RR, 1.04; 95% CI, 1.01-1.08). Estrogen-progestin use that was both recent and long term (>5 years in duration) was more strongly associated with breast cancer risk (RR, 1.57; 95% CI, 1.15-2.14) than similar use of estrogen alone (RR, 1.39; 95% CI, 1.17-1.65). In estrogen-progestin users, risks were similar for sequential and continuous use regimens but perhaps stronger for lobular than ductal breast cancer. Use of progestin alone was associated with a doubling of risk (RR, 2.09; 95% CI, 1.07-4.07 for ever use versus nonuse). Estrogen-progestin use, both sequential and continuous, appears to be more strongly associated with risk of breast cancer than use of estrogen alone.  相似文献   
76.
Weight change and risk of postmenopausal breast cancer (United States)   总被引:8,自引:2,他引:6  
Objective: Although many studies have shown that higher weight increases the risk of postmenopausal breast cancer, some aspects of this association are unclear. In order to examine the risk associated with different patterns of weight change, we analyzed data from a large case–control study of postmenopausal breast cancer. Methods: Participants included women aged 50–79 years (n = 5031) who are newly diagnosed with invasive breast cancer in Massachusetts, New Hampshire, and Wisconsin. Similarly-aged population controls (n = 5255) were selected at random from driver's license files and Medicare beneficiary lists. Height, weight, and information on other breast cancer risk factors were ascertained by structured telephone interviews from 1992 to 1995, and logistic regression was used to estimate multivariable-adjusted odds ratios (OR) and 95% confidence intervals (CI). Results: Women in the top quintile groups for height at age 20, recent weight, and recent body mass index had significantly increased risks of breast cancer. Among women who reached their highest adult weight at younger ages (45 years), increasing weight loss since that age was associated with a reduced risk of postmenopausal breast cancer (OR 0.90, CI 0.84–0.98, per 5 kg). However, weight loss among women whose highest weight occurred after age 45 was not associated with risk (OR 1.00, CI 0.95–1.05, per 5 kg). Weight gain since the lowest adult weight increased risk by 8% for each 5 kg of gain (OR 1.08, CI 1.06–1.11). Temporary weight cycling (weight loss followed by weight gain) was not associated with increased risk. Conclusions: Weight gain clearly increased risk of postmenopausal breast cancer. These data lend further support to efforts aimed at helping women avoid weight gain as they age.  相似文献   
77.
78.
Eleven patients received four consecutive weekly cycles of human recombinant interleukin 2 (IL-2) by continuous infusion for 4 days/week. Two dose levels were tested, 1 and 3 X 10(6) units/m2/day. Toxicities experienced by most patients included fever, rigors, fatigue, anemia, eosinophilia, and liver function abnormalities. All side effects from treatment reversed and no severe or life-threatening problems occurred. A marked lymphocytosis was seen following the 4 weeks of therapy. Fresh lymphocytes obtained during this lymphocytosis mediated enhanced destruction in vitro of a natural killer cell-resistant tumor cell line (Daudi). The increase in the absolute number of circulating lymphocytes and their enhanced ability to mediate direct lysis of Daudi targets resulted in a greater than 100-fold mean increase in cytotoxic potential by the end of IL-2 treatment. One patient, with renal carcinoma, who was treated at 3 X 10(6) units/m2/day experienced a sustained measurable response with greater than 50% regression of pulmonary and hepatic metastases. Five patients were retreated with a second course of IL-2, lasting 4 weeks. This therapy was well tolerated in four of these five patients, with similar immunological changes occurring. No further antitumor responses were seen in these patients. Thus, a relatively well tolerated immunotherapy regimen using IL-2 can induce dramatic increases in lymphocyte number and augment their in vitro antitumor reactivity.  相似文献   
79.
Hepatic DNA damage was demonstrated by alkaline DNA unwinding/hydroxylapatitebatch chromatography in male B6C3F1 mice treated with non-necrogenicdoses of 1,2-di-chloroethane, l-bromo-2-chloroethane, and 1,2-dibromo-ethane.Intraperitoneal administration of 0.5 mmol/kg of l-bromo-2-chloroethaneand 1,2-dibromoethane produced similar levels of DNA damage.A 4-fold higher dose of 1,2-di-chloroethane (2.0 mmol/kg) wasrequired to produce a comparable effect.  相似文献   
80.
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