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991.
992.
The aim of this study is to summarize published empirical data describing the predictors of adhering to screening practices and choosing to have prophylactic surgery in women at increased risk for breast and ovarian cancer. Pubmed, Psychinfo and Cinahl databases were searched to identify studies on the predictors of adherence to breast and ovarian cancer screening and predictors of having a prophylactic mastectomy or salpingo-oophorectomy. We found 37 empirical studies that met our inclusion criteria. The main predictors of the use of preventive measures are related to DNA test results, socio-demographic characteristics, and psychological outcome measures. It is concluded that there is no unequivocal relationship between age, education, risk perception, or anxiety and adherence to breast and ovarian cancer screening practices. Worrying about cancer is associated with a higher adherence to screening practices.  相似文献   
993.
New immunosuppressants are said to be superior to cyclosporine due to their higher incidence of steroid sparing and to the reduced incidence of side-effects. From May 1992 to February 1995, 79 adults underwent primary liver transplantation using cyclosporine A (Sandimmun)-based triple drug immunosuppression. Nine patients who died early after liver transplantation due to reasons unrelated to immunological problems were excluded from this analysis. The long-term outcome of the remaining 70 patients was prospectively studied in relation to steroid and azathioprine withdrawal. They were re-evaluated 6-monthly in relation to liver and kidney function; cholesterolemia, infection, de novo diabetes mellitus and arterial hypertension, malignancy, ophthalmological and osteomuscular diseases. In case of rejection occurring during or after steroid tapering, patients were switched, by protocol, to tacrolimus therapy. Median follow-up was 81 months (range 60–96). Forty-four patients (62.8 %) were biopsied 5 years after transplant; 20 patients (28.6 %) were biopsied at a median follow-up of 32 months (range 7.8–47). Six patients (8.6 %) who refused biopsies more than 1 year after liver transplantation had normal liver values throughout the whole follow-up period. Five-year actual patient and graft survivals were 75 % and 65.8 %, respectively, for the whole group (n = 79) and 85.7 % and 74.3 % for the studied group (n = 70). Steroids could be withdrawn in all but two patients (97.1 %) at a median time of 7 months (range 3–42). Steroids were restarted in six patients (8.6 %) for extrahepatic reasons. Freedom from steroids was thus observed in 62 patients (88.6 %). Seven patients (10 %) had rejection after steroid tapering; six were switched to tacrolimus. Two patients (2.9 %) needed retransplantation because of acute and chronic rejection whilst still being on full immunosuppression. In total, three patients (4.3 %) had histological signs of chronic rejection during follow-up. At 5 years post-transplant, 66.6 % and 13.3 % of the 60 patients at risk were on cyclosporine and tacrolimus monotherapy, respectively; 93.3 % were steroid-free. Mean creatinine and cholesterol levels were 1.56 ± 1.3 mg/dl and 193.5 ± 56.6 mg/dl; incidences of de novo arterial hypertension, insulin dependent diabetes mellitus were 26.6 % and 13.3 %. Two patients (2.8 %) developed post-transplant lymphoproliferative disease, two (2.8 %) had skin cancer. Cyclosporine-based immunosuppression allows safe steroid withdrawal in most patients and cyclosporine monotherapy can be achieved in two-thirds without compromising graft and patient survival. Results of new immunosuppressive strategies should be approached with caution, especially when considering steroid sparing and the incidence of side-effects. Received: 12 July 2000 Revised: 15 December 2000 Accepted: 11 September 2001  相似文献   
994.
We present the result of the cytogenetic study of a case of osteosarcoma that revealed a very complex karyotype with a modal chromosome number of 93 and several structural chromosomal abnormalities.  相似文献   
995.
996.
We report a 13-year-old soccer player with osteonecrosis of the talus and a large carticular fragment. The defect was revitalized with curettage and drilling and filled with autologous bone graft followed by the fixation of the carticular fragment with two conventional lag screws. Screw placement was such that they could be removed arthroscopically. Healing was uneventful. Eighteen months postoperative hardware was indeed removed arthroscopically. He returned to his former competitive level without restrictions or complaints.  相似文献   
997.
Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7–1.5) and 0.7 cm (range 0.5–0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy.  相似文献   
998.

Purpose

To study the impact of MRI-guided treatment planning on dose/volume parameters in pulsed dose rate (PDR) brachytherapy (BT) for cervical cancer. Additionally, we investigated the potential benefit of an intracavitary/interstitial (IC/IS) modification of the classical tandem ovoid applicator.

Material and methods

For 24 patients we compared Standard PDR BT plans, Scaled Standard plans and MRI-guided Optimised plans. The total EBRT/BT prescribed dose to Manchester point A or to 90% of the HR-CTV (D90 HR-CTV) [1] expressed in EQD2 was 80 Gyαβ10 in 17 patients (Period I) and 84 Gyαβ10 in 7 patients (Period II). The constraints to 2 cm3 of the OAR were 90 Gyαβ3 for bladder and 75 Gyαβ3 for rectum, sigmoid and bowel. Most cases were treated with a traditional intracavitary tandem ovoid applicator. In 6 patients we used a newly designed combined IC/IS modification for the second PDR fraction and investigated the benefit of the interstitial part.

Results

The average gain of MRI-guided optimisation expressed in D90 HR-CTV was 4 ± 9 Gyαβ10 (p < 0.001) and 10 ± 7 Gyαβ10 (p = 0.003) in the two periods. The dose to 2 cm3 of the OAR met the constraints. In the group that was treated with the combined IC/IS approach, we could increase the D90 HR-CTV for the second PDR fraction with 5.4 ± 4.2 Gyαβ10 (p = 0.005) and the D100 with 4.8 ± 3.1 Gyαβ10 (p = 0.07).

Conclusions

Three-dimensional MRI-guided treatment planning and optimisation improves the DVH parameters compared to conventional planning strategies. Additional improvement can be achieved by using a combined IC/IS approach.  相似文献   
999.
In a large percentage of the infants who die in the neonatal intensive care setting, an end-of-life decision was made before death, usually a decision to forego life-sustaining treatment. This was confirmed in a recent study in The Netherlands that showed also that a minority of cases include the administration of drugs to hasten death, usually in patients with severe congenital multiple or central nervous system anomalies. Over 80% of Dutch pediatricians support this option under certain conditions. Almost all pediatricians are of the opinion that these cases have to be subject to public review, but they favor review by a committee of independent medical, judicial, and ethical professionals rather than by the public prosecutor. A discussion group on this subject recently made a proposal for such a reviewing procedure to the Dutch governmental authorities and described the requirements concerning end-of-life decisions in neonatal medicine. Proper handling of ethical aspects of medical treatment including review and feedback after end-of-life decisions can contribute to high standards of quality of care.  相似文献   
1000.
Impact of diaphragmatic paralysis after cardiothoracic surgery in children.   总被引:9,自引:0,他引:9  
OBJECTIVES: We sought to determine the prevalence and clinical impact of diaphragmatic paralysis caused by phrenic nerve injury after cardiothoracic surgery in children. METHODS: A search of cardiology, radiology, and hospital databases identified 170 episodes of diaphragmatic paralysis after cardiothoracic surgery in 168 children operated on from 1985 to 1997. Medical records were reviewed to determine demographics, details of the operation and postoperative course, diagnostic features and management of diaphragmatic paralysis, and follow-up status. RESULTS: The prevalence of diaphragmatic paralysis was 1.6% (95% confidence interval 1.4%-1.8%). Median age at operation was 6 months (range <1 day-14.4 years). Median time from the operation to the initial investigation was 5 days (range <1 day-61 days), with 57% of patients receiving mechanical ventilation at diagnosis. Diaphragmatic plication was performed in 40% of the patients at a median interval from the initial investigation of 15 days (range 3 days-11.1 months). Significant independent factors associated with increased postoperative hospital stay were lower patient weight at operation, previous cardiothoracic operations, bilateral diaphragmatic paralysis, increased interval from operation to investigation, mechanical ventilation at the time of investigation, and diaphragmatic plication. Confirmed recovery of diaphragmatic function was noted before hospital discharge in only 15 episodes. CONCLUSIONS: Diaphragmatic paralysis complicating cardiothoracic surgery continues to occur in the current era, with a significant impact on morbidity. Smaller patients with bilateral hemidiaphragmatic paralysis, requiring mechanical ventilation, may represent a higher risk subgroup to target for increased diagnostic suspicion and more aggressive management; early spontaneous recovery is rare.  相似文献   
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