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41.
42.
ObjectiveTo identify essential structures, processes, outcomes, and challenges of nursing practice in fetal care and to identify research priorities for nurses in fetal care.DesignWe used a modified Delphi method to achieve consensus.SettingA secure online survey platform.ParticipantsThe expert panel included nurses from the Fetal Therapy Nurse Network. In addition, a multidisciplinary research jury included members of the North American Fetal Therapy Network (NAFTNet).MethodsWe collected data in three consecutive rounds with online questionnaires that were e-mailed to panelists. We used content analysis to generate statements from an initial round of open-ended questions. Statements met consensus if 75% of the panelists ranked it as greater than or equal to 6 on a 1-to-7 Likert scale.ResultsThe 48 nurse panelists and 11 multidisciplinary jury members described a range of nursing processes. Consensus was reached on 96 statements related to the structure, processes, outcomes, and research priorities of nurses in fetal care.ConclusionThe participants agreed that an expert fetal care nursing team is necessary to provide care to women and families during fetal diagnosis and treatment. Ideally, these nurses should coordinate care and provide direct clinical care (e.g., patient counseling) in outpatient prenatal settings and inpatient settings when fetal surgery is involved. Nurses should be supported to take on leadership roles in program development, research, quality improvement, and professional development with relevant professional organizations.  相似文献   
43.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
44.
Signal transduction by the platelet Fc receptor   总被引:6,自引:1,他引:6  
Anderson  GP; Anderson  CL 《Blood》1990,76(6):1165-1172
We have evaluated the mechanism by which crosslinking human platelet Fc receptor (FcR) for IgG triggers platelet aggregation and the platelet release reaction. Platelet FcR was crosslinked by incubating purified human platelets with anti-FcRII monoclonal antibody and F(ab')2 anti- mouse Ig. The resultant [Ca2+]i increase, monitored by Fura-2 and measured in the absence of extracellular Ca2+, reached a peak of 750 +/- 50 nmol/L. The effects of cyclooxygenase inhibitors, aspirin and indomethacin, and a phospholipase A2 inhibitor, dibromoacetophenone, were examined. Regardless of the inhibitor, at least 25% of the [Ca2+]i increase remained. Thrombin (0.2 U/mL) stimulated an immediate [Ca2+]i increase that reached 1.95 +/- 0.8 mumol/L. The [Ca2+]i increase generated by thrombin was only slightly reduced by these inhibitors. Crosslinking the FcRII of platelets resulted in a fivefold increase in the production of [3H]inositol phosphates, (IP) which, in the absence of extracellular Ca2+ was insensitive to aspirin. The activation of a [Ca2+]i increase along with the measured increases in IP indicate that FcRII crosslinking leads to the activation of phospholipase C (PLC). In contrast to thrombin, platelet activation via FcRII depends to a large extent on arachidonic acid metabolites. However, neither cyclooxygenase nor phospholipase A2 inhibitors completely blocked FcRII-stimulated [Ca2+]i increase. These observations led us to propose that crosslinking of platelet FcRII initially activates PLC.  相似文献   
45.
Chondromalacia patellae: assessment with MR imaging   总被引:10,自引:0,他引:10  
Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.  相似文献   
46.
47.
Infected pancreatic fluid collections: percutaneous catheter drainage   总被引:5,自引:0,他引:5  
Freeny  PC; Lewis  GP; Traverso  LW; Ryan  JA 《Radiology》1988,167(2):435-441
Thirty-eight infected pancreatic fluid collections in 23 patients with acute or chronic pancreatitis were drained percutaneously following initial diagnosis with computed tomography and fine-needle aspiration. Fifteen (65.2%) patients were cured completely without surgery. Eight (34.8%) patients required some type of surgery despite successful treatment of the fluid collection, and in two (6.5%) the collection recurred after catheter removal. Complications occurred in three (13%) patients, but only one complication (4%), empyema, was a direct result of catheter drainage. Catheter drainage time averaged 29 days for 16 patients with isolated collections and 96 days and 104 days for patients with collections with pancreatic duct fistulas (nine patients) or gastrointestinal fistulas (14 patients), respectively. This study confirms that infected pancreatic fluid collections can be safely and effectively treated with percutaneous catheter techniques in most patients.  相似文献   
48.

Introduction

In 2006 the National Confidential Enquiry into Patient Outcome and Death undertook a large prospective study of trauma care, which revealed several findings pertaining to the management of head injuries in a sample of 493 patients.

Methods

Case note data were collected for all trauma patients admitted to all hospitals accepting emergencies in England, Wales, Northern Ireland and the Channel Islands over a three-month period. Severely injured patients with an injury severity score (ISS) of ≥16 were included in the study. The case notes for these patients were peer reviewed by a multidisciplinary group of clinicians, who rated the overall level of care the patient received.

Results

Of the 795 patients who met the inclusion criteria for the study, 493 were admitted with a head injury. Room for improvement in the level of care was found in a substantial number of patients (265/493). Good practice was found to be highest in high volume centres. The overall head injury management was found to be satisfactory in 84% of cases (319/381).

Conclusions

This study has shown that care for trauma patients with head injury is frequently rated as less than good and suggests potential long-term remedies for the problem, including a reconfiguration of trauma services and better provision of neurocritical care facilities.  相似文献   
49.

Background

Anaplastic thyroid carcinoma (ATC) is the most aggressive form of thyroid cancer and it has an extremely poor prognosis. Rapid airway compromise is the main cause of death in patients with ATC.

Methods

The present study is based on a retrospective review of clinical data of patients with ATC treated over the last decade in a tertiary referral center.

Results

Between January 1998 and December 2010, 31 patients (13 males: 18 females) with a mean age of 74 years (range: 54–90 years) had a diagnosis of ATC made on fine-needle aspiration (n = 29) or biopsy (n = 2). Eight patients underwent total thyroidectomy and lymph node dissection, and five patients had attempted surgery but the procedure was abandoned because of inoperability. Airway compromise was clinically apparent in 11 patients. Five patients had tracheal stents inserted, with a median survival of 2 months (range: 1–36 months). In the whole cohort, 29 patients died of the disease, with a mean survival of 7 months (range: 1–36 months).

Conclusions

Survival of patients with undifferentiated thyroid cancer is severely compromised by airway obstruction. Palliation with tracheal stenting can rescue catastrophic airway obstruction but offers minimal survival benefit.  相似文献   
50.
Intracisternal injection of 30 micrograms 6-hydroxydopamine was used to destroy meningeal cells in the newborn hamster. After 20 or 30 days the cerebella of treated animals showed severe morphological alterations including: an absence of distinct folia anterior to the primary fissure; a disruption of lamination in the same region by the displacement of both Purkinje cells and cerebellar interneurons; a reduction in size and frequency of branching of the medullary tree with anomalous anterobasal branches and splaying; reductions in the area of the molecular layer, the total area occupied by granule cells, the length of the pial surface and the length of the Purkinje cell layer of 29, 21, 57 and 27%, respectively; disorganization of the radially organized glial scaffold by outgrowth of Bergmann glial fibers and displacement of their cell bodies, the Golgi epithelial cells, and anomalous orientation, polarity, size and branching frequency of Purkinje cell dendritic trees. These findings support our earlier hypothesis that the initial destruction of meningeal cells destabilizes the cerebellar surface (basal lamina and glia limitans superficialis) and disorganizes the glial scaffold, while the neuronal cerebellar malformations are secondary to this glial defect.  相似文献   
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