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排序方式: 共有1114条查询结果,搜索用时 15 毫秒
41.
42.
Sickle cell disease: imaging of cerebrovascular complications 总被引:3,自引:0,他引:3
43.
Comparative intraocular pressure measurements with the pneumatonograph and Goldmann tonometer. 总被引:6,自引:0,他引:6
Comparative intraocular pressure measurements made with the pneumatonograph and the Goldmann tonometer showed close agreement with a statistically higher mean pressure when using the pneumatonograph. Significant changes in mean pressure differences between the two instruments were seen upon changing the pneumatonograph calibration and with change in the order of testing (which instrument was used initially). However, transient biologic changes in an individual eye producing minute-to-minute fluctuations in intraocular pressure may be equal to or larger than differences in measurement between instruments. 相似文献
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46.
Combined resection of the liver and inferior vena cava for hepatic malignancy 总被引:12,自引:0,他引:12 下载免费PDF全文
OBJECTIVE: The objective of this paper is to review the results of combined resection of the liver and inferior vena cava for hepatic malignancy. The morbidity and mortality along with preliminary survival data are assessed in order to determine the utility of this aggressive approach to otherwise unresectable tumors. SUMMARY BACKGROUND DATA: Involvement of the inferior vena cava has traditionally been considered a contraindication to resection for advanced tumors of the liver because the surgical risks are high and the long-term prognosis is poor. Progress in liver surgery allows resection in some cases. METHODS: Twenty-two patients undergoing hepatic resection from 1997 to 2003, that also required resection and reconstruction of the inferior vena cava (IVC), were reviewed. The median age was 49 years (range 2 to 68 years). Resections were carried out for: hepatocellular carcinoma (n = 6), colorectal metastases (n = 6), cholangiocarcinoma (n = 5), gastrointestinal stromal tumor (n = 2), hepatoblastoma (n = 2), and squamous cell carcinoma in 1 patient. Liver resections performed included 13 right trisegmentectomies, 6 right lobectomies extended to include the caudate lobe, and 3 left trisegmentectomies. Complex ex vivo procedures were performed in 2 cases using venovenous bypass while the other 20 cases were performed using varying degrees of vascular isolation. In situ cold perfusion of the liver was used in 1 case. The IVC was reconstructed with ringed Gore-Tex tube graft (n = 14), primarily (n = 6), or with Gore-Tex patches (n = 2). RESULTS: There were 2 perioperative deaths (9%). One cirrhotic patient died of liver failure 3 weeks post operatively and 1 patient with cholangiocarcinoma died of pulmonary hemorrhage secondary to a cavitating pulmonary infection after aspiration pneumonia 6 weeks after resection. Six patients had evidence of postoperative liver failure that resolved with supportive management and 2 patients required temporary dialysis. All vascular reconstructions were patent at last follow-up. With median follow-up of 26 months, 5 patients have died of recurrent malignancy at 44, 40, 32, 26, and 24 months, while an additional patient is alive with disease at 31 months. Actuarial 1-, 3-, and 5-year survivals were 85%, 60%, and 33%, respectively. CONCLUSIONS: IVC involvement by hepatic malignancy does not necessarily preclude resection. Liver resection with reconstruction of the inferior vena cava can be performed in selected cases. The increased risk associated with the procedure appears to be balanced by the possible benefits, particularly when the lack of alternative curative approaches is considered. 相似文献
47.
Expression of VEGF receptors in cocultured neuroblastoma cells 总被引:15,自引:0,他引:15
BACKGROUND: VEGF is best known for its angiogenic properties. We have found that VEGF expression is increased in neuroblastoma cells cocultured with hepatocytes. In addition, we have previously shown that neuroblastoma cells cultured with exogenous VEGF have an increase in the expression of VEGF receptors. Therefore, we hypothesized that the expression of VEGF receptors would be up-regulated in neuroblastoma cells grown in the coculture environment. MATERIALS AND METHODS: Two neuroblastoma cell lines (IMR-32 or SK-N-DZ) are used. These cells are cultured alone and in a coculture system with hepatocytes. Message for VEGF and the VEGF receptors KDR, flt-1, flt-4, neuropilin 1 (NRP-1), and neuropilin 2 (NRP-2) are measured with RT-PCR. Flt-4, NRP-1, and NRP-2 protein expression is measured with Western blot. RESULTS: The receptors KDR and flt-1 are not detected in either cell line in either control or coculture conditions. Message for VEGF and flt-4 is significantly increased in the cocultured IMR-32 cells, while that for NRP-1 and NRP-2 is unchanged in these cells. VEGF and its receptors are unchanged in cocultured SK-N-DZ cells. CONCLUSIONS: Neuroblastoma cells express specific VEGF receptors that are differentially regulated in the different cell lines. These findings suggest that the heterogeneity of neuroblastomas may limit the utility of targeting VEGF and its receptors as sole treatments for the tumor, and that successful therapies will be dependent upon the specific biology of the tumor. 相似文献
48.
Lally KP Lally PA Langham MR Hirschl R Moya FR Tibboel D Van Meurs K;Congenital Diaphragmatic Hernia Study Group 《Journal of pediatric surgery》2004,39(6):829-833
Background
Use of exogenous surfactant in congenital diaphragmatic hernia (CDH) patients is routine in many centers. The authors sought to determine the impact of surfactant use in the premature infant with CDH.Methods
Data on liveborn infants with CDH from participating institutions were collected prospectively. Surfactant use and timing and outcome data were analyzed retrospectively. The authors evaluated the prenatal diagnosis patients as well. The outcome variable was survival to discharge. Odds ratios with confidence intervals were calculated.Results
Five hundred ten infants less than 37 weeks’ gestation were entered in the CDH registry. Infants with severe anomalies (n = 80) were excluded. Information on surfactant use was available for 424 patients. Infants receiving surfactant (n = 209) had a greater odds of death than infants not receiving surfactant (n = 215, odds ratio, 2.17, 95% CI: 1.5 to 3.2; P < .01). In prenatally diagnosed infants with immediate distress, there was a trend toward worse survival rates among those receiving surfactant at 1 hour (52 patients) versus those that did not (93 patients; odds ratio, 1.93, 95% CI: 0.96 to 3.9; P < .07).Conclusions
Surfactant, as currently used, is associated with a lower survival rate in preterm infants with CDH. The use of surfactant replacement in premature infants with CDH can be recommended only within the context of a randomized clinical trial. 相似文献49.
The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma. 相似文献
50.