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81.
To enhance individual and family health during recovery from heart surgery, this study employed nursing interventions based on self-efficacy and family stress theory during the hospitalization period and for 3 months thereafter. The effectiveness of the interventions were assessed through a randomized trial in which 67 prospective bypass and valve surgery patients, aged 30-77 years, and their spouses, were allocated either the experimental interventions or usual care and followed for 6 months. At 3 months post-surgery, the only statistically significant differences between the experimentals and controls were on perceived self-efficacy for lifting and tolerating emotional distress. At 6 months no significant differences were found on individual or family measures. Analyses revealed that age, gender and preoperative cardiac status significantly affected individual recovery. The study is continuing with a larger sample in order to explicate the recovery process and to better determine whether a low intensity nursing intervention can effect changes in individual and family recovery.  相似文献   
82.
The preparation of novel heterocyclic base modified adenosine analogues, the 4-aminopyrrolo[2,3-d]pyridazine nucleosides, is described. Crucial to their successful preparation was the use of the pyrrole glycoside intermediates 3-cyano-2-formyl-1-(2,3,5-tri-O-benzyl-beta-D-ribofuranosyl)pyrrole (11) and 3-cyano-2-formyl-1-(2,3,5-tri-O-benzyl-beta-D-arabinofuranosyl)pyrrole (17). Treatment of 11 and 17 with hydrazine dihydrochloride followed by treatment with boron trichloride provided 4-amino-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazine (2) and 4-amino-1-beta-D-arabinofuranosylpyrrolo[2,3-d]pyridazine (3), respectively. 4-Amino-3-bromo-1-beta-D-ribofuranosylpyrrolo[2,3-d]-pyridazine (4) was prepared by a bromination of 4-amino-1-(2,3,5-tri-O-benzyl-beta-D-ribofuranosyl)pyrrolo[2,3-d]pyri daz ine (12) and subsequent removal of the benzyl groups with boron trichloride. Compounds 2-4 were evaluated for antiproliferative and antiviral activity. The tubercidin analogue (2) and its arabinosyl derivative (3) were virtually inactive in all assays. In contrast, the 3-bromo analogue 4 inhibited growth of L1210 and H. Ep. 2 cells. Compound 4 was also active against human cytomegalovirus and herpes simplex virus type 1, but the antiviral activity was not completely separated from cytotoxicity.  相似文献   
83.
When complex prostheses are fabricated, it is expected that at some point maintenance will be necessary. This clinical report documents a 10-year-old maxillary spark erosion prosthesis that had been repaired many times, was discolored, and exhibited significant signs of wear. The metal superstructure was intact; therefore, only the acrylic resin base and teeth needed to be replaced. To reduce both cost and time without the prosthesis for the patient, the rehabilitation was completed within 24 hours.  相似文献   
84.
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease.  相似文献   
85.
Gold weight implants have been used for over 30 years in the setting of eyelid rehabilitation following facial nerve paralysis; however, there has been a renewed interest by ophthalmologists in this reanimation technique in recent years. This article reviews the history of gold weight eyelid implantation and presents the results of gold weight eyelid implantation over a 15-month period in 23 patients. A 92% success rate was obtained (average follow-up, 12 months). Surgical technique and indications are discussed along with postoperative complications.  相似文献   
86.
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.  相似文献   
87.
ABSTRACT: Background: Hands‐and‐knees positioning during labor has been recommended on the theory that gravity and buoyancy may promote fetal head rotation to the anterior position and reduce persistent back pain. A Cochrane review found insufficient evidence to support the effectiveness of this intervention during labor. The purpose of this study was to evaluate the effect of maternal hands‐and‐knees positioning on fetal head rotation from occipitoposterior to occipitoanterior position, persistent back pain, and other perinatal outcomes. Methods: Thirteen labor units in university‐affiliated hospitals participated in this multicenter randomized, controlled trial. Study participants were 147 women laboring with a fetus at ≥37 weeks’ gestation and confirmed by ultrasound to be in occipitoposterior position. Seventy women were randomized to the intervention group (hands‐and‐knees positioning for at least 30 minutes over a 1‐hour period during labor) and 77 to the control group (no hands‐and‐knees positioning). The primary outcome was occipitoanterior position determined by ultrasound following the 1‐hour study period and the secondary outcome was persistent back pain. Other outcomes included operative delivery, fetal head position at delivery, perineal trauma, Apgar scores, length of labor, and women's views with respect to positioning. Results: Women randomized to the intervention group had significant reductions in persistent back pain. Eleven women (16%) allocated to use hands‐and‐knees positioning had fetal heads in occipitoanterior position following the 1‐hour study period compared with 5 (7%) in the control group (relative risk 2.4; 95% CI 0.88–6.62; number needed to treat 11). Trends toward benefit for the intervention group were seen for several other outcomes, including operative delivery, fetal head position at delivery, 1‐minute Apgar scores, and time to delivery. Conclusions: Maternal hands‐and‐knees positioning during labor with a fetus in occipitoposterior position reduces persistent back pain and is acceptable to laboring women. Given this evidence, hands‐and‐knees positioning should be offered to women laboring with a fetus in occipitoposterior position in the first stage of labor to reduce persistent back pain. Although this study demonstrates trends toward improved birth outcomes, further trials are needed to determine if hands‐and‐knees positioning promotes fetal head rotation to occipitoanterior and reduces operative delivery. (BIRTH 32:4 December 2005)  相似文献   
88.
89.
To characterize the lipid and lipoprotein abnormalities in patients with diabetes mellitus and evaluate the risks and benefits of marketed pharmacologic therapies, a MEDLINE search of the National Library of Medicine data base was performed of studies published from January 1966 to March 1994. Clinical trials assessing effects on lipids and lipoproteins, and adverse effects of marketed lipid-lowering agents were extracted. Reviews and other relevant articles were included if they provided information regarding lipid and lipoprotein metabolism or guidelines on the treatment of dyslipidemias in patients with diabetes mellitus. An extensive review of clofibrate was not included. The most common dyslipidemia in patients with poorly controlled insulin-dependent diabetes mellitus (IDDM) is combined elevated triglyceride and cholesterol levels, with reduced high-density lipoprotein (HDL) cholesterol (mixed hyperlipidemia). Hypertriglyceridemia combined with a reduced HDL cholesterol is the most common dyslipidemia in patients with noninsulin-dependent diabetes mellitus, but essentially any pattern of dyslipidemia may be present. Small and dense low-density lipoprotein (LDL), glycosylation of lipoproteins, and increased oxidized lipoproteins may be present in patients with diabetes mellitus; all contribute to accelerated atherosclerotic cardiovascular disease. Insulin therapy generally corrects quantitative lipid abnormalities in patients with IDDM, so drug treatment is seldom indicated. Diet, exercise, and insulin or oral sulfonylureas will improve hypertriglyceridemia and low HDL concentrations, but do not always return them to normal. Drug therapy is indicated when nonpharmacologic measures are inadequate. It is administered based on the effects of each agent on lipids and lipoproteins, patient age, adverse effect profile, patient tolerability, and drug-disease and drug-drug interactions. A fibric acid derivative is the drug of choice for marked hypertriglyceridemia in patients with diabetes mellitus. Niacin can worsen glycemic control, but it may be required in severe hypertriglyceridemia, hypercholesterolemia, or mixed hyperlipidemia. Bile-acid binding resins may accentuate hypertriglyceridemia but may be useful in selected patients with marked hypercholesterolemia and normal triglycerides. Hydroxymethylglutaryl coenzyme A reductase inhibitors are preferred in patients with elevated LDL cholesterol and mild hypertriglyceridemia. Patients with marked lipid abnormalities or mixed hyperlipidemias may require carefully dosed combinations of lipid-lowering drugs.  相似文献   
90.
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