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91.
The safe and effective management of aggression has become an increasingly critical skill for mental health nurses, particularly those working in acute inpatient settings. There is considerable evidence to suggest that the psychological constructs of self-efficacy and locus of control are closely related to work performance in a variety of occupations. By drawing upon literature published in the past 15 years, this paper highlights this evidence and draws attention to the relationship between self-efficacy and locus of control. The central argument of the paper is that there may be direct relationships among mental health nurses” self-efficacy, their degree of internality or externality in relation to locus of control, and their ability to safely and effectively manage aggressive incidents. We argue the need to further investigate these relationships and discover whether these variables can be modified through professional development activities. 相似文献
92.
Objective The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures
of the pars interarticularis.
Method The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with
incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level,
location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI
images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns
were characterised on follow-up CT imaging.
Results Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial
cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either
complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures
in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%)
showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly
graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI,
67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema.
Conclusions Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction
of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management.
CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability
to fully depict the cortical integrity of incomplete fractures of the pars, but the presence of marrow oedema on fat-saturated
T2-weighted sequences is a useful means of detecting acute spondylolysis. 相似文献
93.
Imran Liaquat Laurence T Dunn James A R Nicoll Graham M Teasdale John D Norrie 《Journal of neurosurgery》2002,96(1):90-96
OBJECT: The apolipoprotein E-epsilon4 (APOE-epsilon4) allele is associated with poor outcome after head injury and spontaneous intracerebral hemorrhage (SICH). The aims of this study were to determine if patients in whom one or more APOE-epsilon4 alleles are present are more likely to sustain intracranial mass lesions after head injury and to determine whether there is an isoform-specific effect on the size of the intracranial hematoma. METHODS: The authors performed a computerized volumetric analysis of 142 hematomas visible on computerized tomography (CT) scans obtained in 129 patients. The APOE genotype was determined by subjecting buccal smear samples to polymerase chain reaction and restriction enzyme digestion. Allele frequencies were similar in head-injured patients with and without intracranial hematomas (p = 0.36). Univariate analysis revealed that in those patients with one or more APOE-epsilon4 alleles hematoma volume was greater (cube root-transformed values) than that found in patients without the APOE-epsilon4 allele (3.1 cm compared with 2.5 cm, p = 0.0039). The results of univariate analysis also suggested significant effects of patient age, injury severity (mild, moderate, or severe according to admission Glasgow Coma Scale scores) and hematoma location (extraaxial, intraaxial, or both) on hematoma volume. The mechanism of injury (assault, fall, or other) was marginally associated with hematoma volume (p = 0.052). Time from injury to CT scan, hypoxia, and hypotension had no significant effect on hematoma volume. The results of multiple linear regression analysis showed that the presence of an APOE-epsilon4 allele and an extraaxial hematoma location were independent predictors of hematoma volume, after adjusting for patient age, hours between injury and CT scan, injury severity, and injury mechanism. CONCLUSIONS: Larger hematomas were found in head-injured patients with one or more APOE-epsilon4 alleles than in patients without the allele. This may contribute to the poorer outcomes observed in these patients. 相似文献
94.
Margaret M. Dunn 《American journal of surgery》2010,200(4):558-152
A new job is a great opportunity to change and enhance your professional and personal life. Your new position will be defined through negotiation with the parties supporting your new position. Whether your new job is your first or your last, with a large organization or solo, urban or rural, the goal is the same, to define your expectations and communicate clearly to create a situation that you will find professionally and personally fulfilling. 相似文献
95.
T. B. Dunn H. Noreen K. Gillingham D. Maurer O. G. Ozturk T. L. Pruett R. A. Bray H. M. Gebel A. J. Matas 《American journal of transplantation》2011,11(10):2132-2143
Single‐antigen bead (SAB) testing permits reassessment of immunologic risk for kidney transplantation. Traditionally, high panel reactive antibody (PRA), retransplant and deceased donor (DD) grafts have been associated with increased risk. We hypothesized that this risk was likely mediated by (unrecognized) donor‐specific antibody (DSA). We grouped 587 kidney transplants using clinical history and single‐antigen bead (SAB) testing of day of transplant serum as (1) unsensitized; PRA = 0 (n = 178), (2) third‐party sensitized; no DSA (n = 363) or (3) donor sensitized; with DSA (n = 46), and studied rejection rates, death‐censored graft survival (DCGS) and risk factors for rejection. Antibody‐mediated rejection (AMR) rates were increased with DSA (p < 0.0001), but not with panel reactive antibody (PRA) in the absence of DSA. Cell‐mediated rejection (CMR) rates were increased with DSA (p < 0.005); with a trend to increased rates when PRA>0 in the absence of DSA (p = 0.08). Multivariate analyses showed risk factors for AMR were DSA, worse HLA matching, and female gender; for CMR: DSA, PRA>0 and worse HLA matching. AMR and CMR were associated with decreased DCGS. The presence of DSA is an important predictor of rejection risk, in contrast to traditional risk factors. Further development of immunosuppressive protocols will be facilitated by stratification of rejection risk by donor sensitization. 相似文献
96.
BACKGROUND: In men with spinal cord injury (SCI), fertility is impaired because of a combination of ejaculatory dysfunction and poor semen quality. We hypothesized that ultrastructural and metabolic abnormalities of sperm could be an underlying factor in infertility in these men. METHODS: To investigate mechanisms contributing to the abnormal sperm parameters, we analyzed seminal constituents and sperm ultrastructure in ejaculates from 7 men with SCI and compared them with 5 control subjects. Sperm adenosine triphosphate (ATP) content was measured using a firefly luciferase bioluminescent assay kit, and ultrastructure was evaluated by electron microscopy. Seminal oxidative stress (8-iso-prostaglandin F-2alpha [8-iso-PGF2alpha]) and transforming growth factor-beta1 (TGF-beta1) levels were measured by specific enzyme-linked immunoabsorbent assay kits. RESULTS: Semen samples from men with SCI showed azoospermia (3) and severe asthenospermia (2; motility 0-5%). A majority (65%) of sperm from asthenospermic samples showed degenerative changes and significant axonemal defects. Incubation of normal sperm with SCI seminal plasma induced a concentration-dependent decrease in sperm motility (43%) accompanied by a significant drop in intracellular ATP content (33%). Semen samples from men with SCI exhibited levels of 8-iso-PGF2alpha 3.5-fold higher than those from controls and levels of TGF-beta1 that were 10% higher than those from controls. CONCLUSION: Our results suggest that seminal constituents of men with SCI are detrimental to sperm movement and that ultrastructural degenerative changes may contribute to the impaired sperm motility and viability seen in these patients. These preliminary results must be confirmed in larger patient populations and longitudinal studies. 相似文献
97.
Matas AJ Payne WD Sutherland DE Humar A Gruessner RW Kandaswamy R Dunn DL Gillingham KJ Najarian JS 《Annals of surgery》2001,234(2):149-164
OBJECTIVE: To review a single center's experience and outcome with living donor transplants. SUMMARY BACKGROUND DATA: Outcome after living donor transplants is better than after cadaver donor transplants. Since the inception of the authors' program, they have performed 2,540 living donor transplants. For the most recent cohort of recipients, improvements in patient care and immunosuppressive protocols have improved outcome. In this review, the authors analyzed outcome in relation to protocol. METHODS: The authors studied patient and graft survival by decade. For those transplanted in the 1990s, the impact of immunosuppressive protocol, donor source, diabetes, and preemptive transplantation was analyzed. The incidence of rejection, posttransplant steroid-related complications, and return to work was determined. Finally, multivariate analysis was used to study risk factors for worse 1-year graft survival and, for those with graft function at 1 year, to study risk factors for worse long-term survival. RESULTS: For each decade since 1960, outcome has improved after living donor transplants. Compared with patients transplanted in the 1960s, those transplanted in the 1990s have better 8-year actuarial patient and graft survival rates. Death with function and chronic rejection have continued to be a major cause of graft loss, whereas acute rejection has become a rare cause of graft loss. Cardiovascular deaths have become a more predominant cause of patient death; infection has decreased. Donor source (e.g., ideally HLA-identical sibling) continues to be important. For living donor transplants, rejection and graft survival rates are related to donor source. The authors show that patients who had preemptive transplants or less than 1 year of dialysis have better 5-year graft survival and more frequently return to full-time employment. Readmission and complications remain problems; of patients transplanted in the 1990s, only 36% never required readmission. Similarly, steroid-related complications remain common. The authors' multivariate analysis shows that the major risk factor for worse 1-year graft survival was delayed graft function. For recipients with 1-year graft survival, risk factors for worse long-term outcome were pretransplant smoking, pretransplant peripheral vascular disease, pretransplant dialysis for more than 1 year, one or more acute rejection episodes, and donor age older than 55. CONCLUSIONS: These data show that the outcome of living donor transplants has continued to improve. However, for living donors, donor source affects outcome. The authors also identify other major risk factors affecting both short- and long-term outcome. 相似文献
98.
The influence of a bupivacaine and fentanyl epidural infusion after epidural fentanyl in patients allowed to ambulate in early labor 总被引:2,自引:0,他引:2
Connelly NR Parker RK Lucas T El-Mansouri M Komanduri V Nayak P Gutta S Gibson C Dunn SM 《Anesthesia and analgesia》2001,93(4):1001-1005
Epidural fentanyl after a lidocaine and epinephrine test dose provides adequate analgesia and allows for ambulation during early labor. This study was designed to determine the influence of an epidural infusion of bupivacaine plus fentanyl administered after initiation of epidural labor analgesia with fentanyl. Specifically, we evaluated whether there is an increase in motor block or an increased time to request for further analgesic medication. Fifty-one laboring primigravid women at <5 cm cervical dilation who requested epidural analgesia were enrolled. After a 3-mL epidural test dose of 1.5% lidocaine with epinephrine (5 microg/mL), patients received fentanyl 100 microg via the epidural catheter. They then randomly received either an infusion (10 mL/h) of 0.0625% bupivacaine with fentanyl (3 microg/mL) or an infusion of preservative-free saline. After the administration of the initial analgesic, pain scores and side effects were recorded for each patient at 10, 20, and 30 min, every 30 min thereafter, and at the time of request for additional analgesic medication, by an observer blinded to the technique used. There were no demographic differences between the two groups. The mean duration of analgesia (time from initial dose to request for additional analgesia) was increased in the group that received a continuous infusion of bupivacaine and fentanyl compared with the Saline group (198 +/- 86 vs 145 +/- 50 min; P < 0.009). Side effects were similar between the two groups. No patient in either group experienced any detectable motor block. Fourteen patients chose to ambulate in the Saline group, and 12 patients chose to ambulate in the Infusion group. In early laboring patients, a continuous infusion of 0.0625% bupivacaine infusion with fentanyl (3 microg/mL) prolonged the duration until top-up was required, after epidural fentanyl 100 microg after a lidocaine and epinephrine test dose, and did not cause any clinically detectable motor block. IMPLICATIONS: A 0.0625% bupivacaine and fentanyl (3 microg/mL) infusion, when added to epidural fentanyl (100 microg), prolongs the analgesic duration without increasing motor block in women in early labor. 相似文献
99.
Lessons learned from more than 1,000 pancreas transplants at a single institution 总被引:30,自引:0,他引:30 下载免费PDF全文
Sutherland DE Gruessner RW Dunn DL Matas AJ Humar A Kandaswamy R Mauer SM Kennedy WR Goetz FC Robertson RP Gruessner AC Najarian JS 《Annals of surgery》2001,233(4):463-501
OBJECTIVE: To determine outcome in diabetic pancreas transplant recipients according to risk factors and the surgical techniques and immunosuppressive protocols that evolved during a 33-year period at a single institution. SUMMARY BACKGROUND DATA: Insulin-dependent diabetes mellitus is associated with a high incidence of management problems and secondary complications. Clinical pancreas transplantation began at the University of Minnesota in 1966, initially with a high failure rate, but outcome improved in parallel with other organ transplants. The authors retrospectively analyzed the factors associated with the increased success rate of pancreas transplants. METHODS: From December 16, 1966, to March 31, 2000, the authors performed 1,194 pancreas transplants (111 from living donors; 191 retransplants): 498 simultaneous pancreas-kidney (SPK) and 1 simultaneous pancreas-liver transplant; 404 pancreas after kidney (PAK) transplants; and 291 pancreas transplants alone (PTA). The analyses were divided into five eras: era 0, 1966 to 1973 (n = 14), historical; era 1, 1978 to 1986 (n = 148), transition to cyclosporine for immunosuppression, multiple duct management techniques, and only solitary (PAK and PTA) transplants; era 2, 1986 to 1994 (n = 461), all categories (SPK, PAK, and PTA), predominantly bladder drainage for graft duct management, and primarily triple therapy (cyclosporine, azathioprine, and prednisone) for maintenance immunosuppression; era 3, 1994 to 1998 (n = 286), tacrolimus and mycophenolate mofetil used; and era 4, 1998 to 2000 (n = 275), use of daclizumab for induction immunosuppression, primarily enteric drainage for SPK transplants, pretransplant immunosuppression in candidates awaiting PTA. RESULTS: Patient and primary cadaver pancreas graft functional (insulin-independence) survival rates at 1 year by category and era were as follows: SPK, era 2 (n = 214) versus eras 3 and 4 combined (n = 212), 85% and 64% versus 92% and 79%, respectively; PAK, era 1 (n = 36) versus 2 (n = 61) versus 3 (n = 84) versus 4 (n = 92), 86% and 17%, 98% and 59%, 98% and 76%, and 98% and 81%, respectively; in PTA, era 1 (n = 36) versus 2 (n = 72) versus 3 (n = 30) versus 4 (n = 40), 77% and 31%, 99% and 50%, 90% and 67%, and 100% and 88%, respectively. In eras 3 and 4 combined for primary cadaver SPK transplants, pancreas graft survival rates were significantly higher with bladder drainage (n = 136) than enteric drainage (n = 70), 82% versus 74% at 1 year (P =.03). Increasing recipient age had an adverse effect on outcome only in SPK recipients. Vascular disease was common (in eras 3 and 4, 27% of SPK recipients had a pretransplant myocardial infarction and 40% had a coronary artery bypass); those with no vascular disease had significantly higher patient and graft survival rates in the SPK and PAK categories. Living donor segmental pancreas transplants were associated with higher technically successful graft survival rates in each era, predominately solitary (PAK and PTA) in eras 1 and 2 and SPK in eras 3 and 4. Diabetic secondary complications were ameliorated in some recipients, and quality of life studies showed significant gains after the transplant in all recipient categories. CONCLUSIONS: Patient and graft survival rates have significantly improved over time as surgical techniques and immunosuppressive protocols have evolved. Eventually, islet transplants will replace pancreas transplants for suitable candidates, but currently pancreas transplants can be applied and should be an option at all stages of diabetes. Early transplants are preferable for labile diabetes, but even patients with advanced complications can benefit. 相似文献
100.
Morris DS Dunn RL Schuster TG Ohl DA Smith GD 《The Journal of urology》2007,178(5):2087-91; discussion 2091
PURPOSE: The motility of testicular derived spermatozoa reflects viability and predicts success during intracytoplasmic sperm injection. Although improvements in sperm motility are seen after incubation for extended periods, no guidelines suggest duration or media use for optimal improvement in motility. MATERIALS AND METHODS: Between July 1999 and February 2005 testicular aspirations were performed on 95 men with azoospermia, including 51 with obstructive azoospermia and 44 with nonobstructive azoospermia. Sperm motility was determined at initial collection and following incubation for 24 or 48 hours in processing media or Ham's F10 + protein. A mixed regression model controlling for testis side, media and baseline motility was created to analyze the change in motility between 24 and 48 hours. RESULTS: Mean motility improved from 3% to 20% at 24 hours and 25% at 48 hours for OA cases and from 0% to 5% at 24 hours and 11% at 48 hours for nonobstructive azoospermia cases. The improvement in motility from 24 to 48 hours was significant for obstructive azoospermia cases (p = 0.001). While media was a nonsignificant factor in regression models, when patients were grouped into categories of motility change there was a significantly better response to F10 compared to processing media (p = 0.03). CONCLUSIONS: Incubation in processing media or Ham's F10 + albumin media improves sperm motility with significant improvement noted between 24 and 48 hours for obstructive azoospermia cases. Ham's F10 + albumin media may provide extra benefit for cases of nonobstructive azoospermia or nerve injury. These results suggest the ideal timing of oocyte retrieval for intracytoplasmic sperm injection correlates with 48-hour sperm incubation for obstructive azoospermia cases, and 24 hours for nonobstructive azoospermia and nerve injury cases. 相似文献